Note: Descriptions are shown in the official language in which they were submitted.
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A method of thermal printing and a thermal printer.
The present invention relates generally to the technique of producing a
printing on a foil by means of a thermal transfer ribbon in an ink transfer
operation.
The present invention relates in particular to the technique of
producing a printing on a foil in a thermal printing operation during a
packaging operation in which the foil is used as a packaging foil or as an
information foil sheet to be applied to or below a wrap around or
packaging foil for packaging a product being an organic or inorganic
product. The examples of products relevant in the present context are
unlimited ranging from toys, cosmetics, consumer products, foodstuffs,
drugs etc. In general, any product which is to be packed in a foil or to be
applied with an information printing after the product has been included in
a separate package may be relevant in the present context. The invention
in general relates to high speed printing and packaging operations in which
the foil on which the printing is to be applied is moved at a speed up to
several hundred millimetres per second.
It is known to print continuous packaging materials constituting foil
materials and other continuous printing media such as paper materials for
producing labels with alfanumeric information and symbols, information,
logos etc. while using a thermal printing or thermal transfer technique.
According to the thermal transfer technique, a thermal transfer ribbon
including an ink is heated at specific locations to an elevated temperature
causing the ink to be fluid and at the same time, the thermal transfer
ribbon is contacted with the print media such as the foil or paper material
in question for causing the transfer of the fluid ink to the foil material or
paper material. In the ink transfer operation, the thermal transfer ribbon is
moved in synchronism with the print media or foil to which the printing is
to be applied and the amount of thermal transfer ribbon material which is
used in a high speed printing and packaging operation performed at a
speed of several hundred millimetres per second may, as will be readily
understood, be extremely high as the thermal transfer ribbon is also moved
at the same high speed as the foil material amount to a speed of
transportation of the order of several hundred metres per second.
Examples of prior art thermal printers of the above kind are described
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in EP 0 157 096, EP 0 176 009, EP 0 294 633, US 5,297,879, US
3,984,809, US 4,650,350, US 4,642,655, US 4,650,350, US 4,712,115,
US 4,952,085, 5,017,943, US 5,160,943, US 5,162,815, US 5,576,751,
US 5,609,425 and US 5,647,679 to which reference is made and which
US patents are hereby incorporated in the present specification by
reference.
From the technical field of paper recorders, it is known to utilize a
thermal transfer ribbon and produce a printing on a piece of paper by
sandwiching the thermal transfer ribbon between a printing head or
recorder head snd the paper sheet on which the printings are to be
produced. It is known in paper recorders of this kind to reduce the speed
of the thermal transfer ribbon relative to the speed of the paper sheet for
saving the amount of thermal transfer ribbon used and consequently obtain
a reduction in costs and improve the economical efficiency of the paper
recorder. Examples of paper recorders of this type are shown in Japanese
patent publication (Kokoku) No. 62-58917), Japanese patent application
laying open (Kokai) No. 63-165169, US 5,121, I36, US 5,372,439 and US
5,415,482. Reference is made to the above patent applications and patents
and the above US patents are hereby incorporated in the present
specification by reference.
An object of the present invention is to provide a novel technique of
producing high speed printings on a print media such a's a foil allowing
substantial material savings as far as the thermal transfer ribbon is
concerned without to any substantial extent deteriorating the quality of the
printing produced as compared to the prior art thermal printing techniques.
It is a further object of the present invention to provide a novel thermal
printing technique rendering it possible with a substantial ribbon material
saving to establish an even improved printing quality as compared to the
prior art thermal printing technique by providing an improved utilization
of the thermal transfer ribbon material as compared to the utilization of the
thermal transfer ribbon material in accordance with the prior art thermal
printing technique.
An advantage of the present invention relates to the fact that a thermal
transfer ribbon material saving up till 80% may be obtained without to any
substantial extent deteriorating the printing quality as compared to the
prior art thermal printing technique.
The above objects and the above advantage together with numerous
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other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a first aspect of the present invention
obtained by means of a method of producing a printing on a surface of a
foil by means of energizable printing means and a thermal transfer ribbon
including an ink which is transferable in an ink transfer operation at
specific locations of the thermal transfer ribbon by heating the specific
locations to an elevated temperature by means of the energizable printing
means causing the ink to be fluid, comprising the following steps:
arranging the thermal transfer ribbon in facial contact with the surface
of the foil,
arranging the energizable printing means in contact with the thermal
transfer ribbon opposite to the foil,
moving the foil and the energizable printing means relative to one
another at a specific speed while pressing the energizable printing means
and the foil together so as to sandwich the thermal transfer ribbon there-
between in a constrained state, and while energizing the energizable
printing means, and
moving the thermal transfer ribbon relative to the energizable printing
means at a reduced speed as compared to the specific speed of the foil
relative to the energizable printing means and consequently moving the
thermal transfer ribbon relative to the foil for causing the ink of the
thermal transfer ribbon to be transferred at the specific locations to the
foil
at specific areas thereof constituting the printing so as to smear the ink of
the thermal transfer ribbon at the specific locations onto the foil through
the motion of the thermal transfer ribbon relative to the foil.
Contrary to the prior art thermal printing technique in which the
thermal transfer ribbon is moved in synchronism with the foil to which the
printing is to be applied in the relative motion of the foil relative to the
energizable printing means, it has been realized that the speed of motion of
the thermal transfer ribbon relative to the energizable printing means may
be reduced as compared to the speed of motion of the foil relative to the
energizable printing means providing a substantial saving of thermal
transfer ribbon material without reducing or deteriorating the quality of the
printings produced. According to the prior art thermal transfer printing
technique, the ink is transferred from a thermal transfer ribbon in a
process of establishing facial contact between the thermal transfer ribbon
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and the foil during the process of moving the foil without causing any
mutual movement between the thermal transfer ribbon and the foil as it has
been considered mandatory to the obtaining of a high quality printing that
no deviation between the movement of the thermal transfer ribbon and the
foil should be allowed which mutual movement inevitably would
deteriorate the printing quality. According to the teachings of the present
invention, it has been realized that the quality of the printing process is by
no means deteriorated provided the thermal transfer ribbon and the foil are
moved relative to one another as the ink transfer process is converted from
a facial contact transfer process into a combined facial contact transfer
process and a smearing process in which the ink is smeared onto the foil
from the thermal transfer ribbon. It is believed that the combined facial
contact transfer operation and the smearing transfer operation of the ink
from the thermal transfer ribbon to the foil provides an increased
utilization of the ink content of the thermal transfer ribbon as compared to
the prior art exclusive facial contact transfer operation.
The energizable printing means may according to the teachings of the
present invention be constituted b~ any appropriate heating means for
causing local heating at specific locations of the thermal transfer ribbon
such as a laser, a pin head or preferably and advantageously a printing
head including individual energizable printing elements.
According to a first implementation or embodiment of the method
according to the first aspect of the present invention, the foil is moved
continuously while the energizable printing means are stationary and the
thermal transfer ribbon is moved relative to the foil and. relative to the
energizable printing means while the energizable printing means are heated
during the ink transfer operation and kept stationary relative to the
energizable printing means while the energizable printing means are not
heated.
According to a second implementation or embodiment of the method
according to the first aspect of the present invention, the foil is moved
continuously while the energizable printing means are stationary and the
thermal transfer ribbon is moved relative to the foil and relative to the
energizable printing means while the energizable printing means are heated
during the ink transfer operation and moved in the reverse direction
relative to the energizable printing means while the energizable printing
means are not heated so as to utilize an used part of the thermal transfer
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ribbon in a subsequent ink transfer operation.
According to a third implementation or embodiment of the method
according to the first aspect of the present invention, the foil is moved
intermittently and kept stationary during the ink transfer operation while
5 the energizable printing means and the thermal transfer ribbon being
moved relative to the stationary foil while the energizable printing means
are heated during the ink transfer operation and moved in the reverse
direction relative to the energizable printing means while the energizable
printing means are not heated so as to utilize an unused part of the thermal
transfer ribbon in a subsequent ink transfer operation.
According to a particular aspect of the present invention as far as the
thermal transfer ribbon saving aspect is concerned, it has been realized
that in numerous instances and in particular in printing on packages,
packaging foils or the like, a substantial thermal transfer ribbon saving
may be obtained provided the printings to be produced are slightly re-
located from one printing operation to another without changing the
geometric configuration of the printing. The above described second and
third implementation or embodiment of the method according to the first
aspect of the present invention constitute embodiments in the present
context to be referred to as "side shift technique" and "retraction
technique", respectively, which are to be considered independent aspects
of the present invention as will be discussed below.
In accordance with the thermal transfer ribbon saving aspect of the
present invention, a specific ink transfer operation is preferably performed
utilizing a part of the thermal transfer ribbon not previously used in a
preceding ink transfer operation and preferably further, the part of the
thermal transfer ribbon used for the specific ink transfer operation being
positioned at least partly transversly offset relative to that part of the
thermal transfer ribbon used in a preceding ink transfer operation in order
to use the maximum amount of the thermal transfer ribbon as compared to
a printing technique not involving "side shifting technique" or "retraction
technique" .
The method according to the first aspect of the present invention may
be operated at a high production rate corresponding to a high specific
speed of the foil relative to the energizable printing means of the order of
50-1,000 mm/sec, such as of the order of 100-500 mm/sec, preferably of
the order of 200-500 mm/sec, while said reduced speed constitutes 20-
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98 % , such as 20-50 % or 50-98 % of said specific speed or alternatively
constitutes 20-30 % , 30-40 % , 40-50 % , 50-60 % , 60-70 % , 70-80 % , 80-
90 % or 90-98 % of said specific speed. Alternatively, the specific speed
may be of the order of 100-200 mm/sec, 200-300 mm/sec, 300-400
mm/sec, 400-500 mm/sec, 500-600 mm/sec, 600-700 mm/sec, 700-800
mm/sec, 800-900 mm/sec or 900-1,000 mm/sec, while said reduced speed
constitutes 20-30 % , 30-40 % , 40-50 % , 50-60 % , 60-70 % , 70-80 % , 80-
90 % or 90-98 % of said specific speed.
The foil material to which the printing is to be applied may be any
appropriate plastics or inorganic or organic material such as a PE or a
PVC foil, a-woven or non-woven plastic foil or a paper foil, aluminum foil
or a combination thereof.
_- The printing head which according to the presently preferred
embodiment of the method according to the first aspect of the present
invention constitutes the energizable printing means may preferably
include energizable printing elements arranged at a mutual spacing of the
order of 0.05 mm - 1 mm, such as of the order of 0.1 mm - 0.5 mm,
preferably approximately 0.1 mm.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a second aspect of the present invention
obtained by means of a method of producing a printing on a surface of a
foil by means of energizable printing means and a thermal transfer ribbon
including an ink which is transferable in an ink transfer operation at
specific locations of the thermal transfer ribbon by heating the specific
locations to an elevated temperature by means of the energizable printing
means causing the ink to be fluid, comprising the following steps:
arranging the thermal transfer ribbon in facial contact with the surface
of the foil,
arranging the energizable printing means in contact with the thermal
transfer ribbon opposite to the foil, and
moving the foil and the energizable printing means relative to one
another at a specific speed while pressing the energizable printing means
and the foil together so as to sandwich the thermal transfer ribbon there-
between in a constrained state, and while energizing the energizable
printing means, for causing the ink of the thermal transfer ribbon to be
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transferred at the specific locations to the foil at specific areas thereof
constituting the printing, the foil being moved continuously while the
energizabie printing means are stationary and the thermal transfer ribbon
being moved relative to the energizable printing means while the
energizable printing means are heated during the ink transfer operation and
moved in the reverse direction relative to the energizable printing means
while the energizable printing means are not heated so as to utilize an used
part of the thermal transfer ribbon in a subsequent ink transfer operation.
The method according to the second aspect of the present invention may
advantageously be implemented in accordance with the above described
preferred and advantageous implementations or embodiments of the
method according to the first aspect of the present invention.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a third aspect of the present invention
obtained by means of a a method of producing a printing on a surface of a
foil by means of energizable printing means and a thermal transfer ribbon
including an ink which is transferable in an ink transfer operation at
specific Locations of said thermal transfer ribbon by heating said specific
locations to an elevated temperature by means of said energizable printing
means causing said ink to be fluid, comprising the following steps:
arranging said thermal transfer ribbon in facial contact with said
surface of said foil,
arranging said energizable printing means in contact with said thermal
transfer ribbon opposite to said foil, and
moving said foil and said energizable printing means relative to one
another at a specific speed while pressing said energizable printing means
and said foil together so as to sandwich said thermal transfer ribbon there-
between in a constrained state, and while energizing said energizable
printing means, for causing said ink of said thermal transfer ribbon to be
transferred at said specific locations to said foil at specific areas thereof
constituting said printing said foil being moved continuously while said
energizable printing means are stationary and said thermal transfer ribbon
being moved relative to said foil and relative to said energizable printing
means while said energizable printing means are heated during said ink
transfer operation and moved in the reverse direction relative to said
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energizable printing means while said energizable printing means are not
heated so as to utilize an used part of said thermal transfer ribbon in a
subsequent -ink transfer operation. The method according to the third
aspect of the present invention may advantageously be implemented in
S accordance with the above described preferred and advantageous
implementations or embodiments of the method according to the first
aspect of the present invention.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a fourth aspect of the present invention
obtained by means of a method of producing a plurality of individual
printings on a surface of a foil by means of energizable printing means and
a thermal transfer ribbon defining a specific width along a transversal
direction thereof and including an ink which is transferable in an ink
transfer operation by heating the thermal transfer ribbon at specific
locations thereof to an elevated temperature by means of the energizable
printing means causing the ink to be fluid, each of the printings defining a
maximum dimension along a direction coinciding with the transversal
direction constituting no more than 50% of the width, comprising the
following steps:
(a) arranging the thermal transfer ribbon in facial contact with the
surface of the foil,
(b) arranging the energizable printing means in contact with the
thermal transfer ribbon opposite to the foil,
(c) moving the foil and the energizable printing means relative to
one another at a specific speed and moving the thermal transfer ribbon
relative to the energizable printing means in the ink transfer operation
while pressing the energizable printing means and the foil together so as to
sandwich the thermal transfer ribbon therebetween in a constrained state,
and simultaneously energizing the energizable printing means causing the
ink to be transferred to the foil at a first area thereof producing a first
printing on the foil at one of the Longitudinal edges of the thermal transfer
ribbon,
(d) relocating the thermal transfer ribbon relative to the energizable
printing means while the energizable printing means are not heated so as to
utilize an unused part of the thermal transfer ribbon and repeating step (c)
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to provide a second printing on the foil at the opposite longitudinal edge of
the thermal transfer ribbon.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a fifth aspect of the present invention
obtained by means of a thermal printer for producing a printing on the
surface of a foil in an ink transfer operation, comprising:
means for supplying the foil to the thermal printer,
a thermal transfer ribbon including an ink which is transferable
in the ink transfer operation at specific locations of the thermal transfer
ribbon by heating the specific locations to an elevated temperature causing
the ink to be fluid,
means for arranging the thermal transfer ribbon i facial contact
with the surface of the foil,
energizable printing means for heating the specific locations of
the thermal transfer ribbon to the elevated temperature in the ink transfer
operation,
means for energizing the energizable printing means,
means for pressing the energizable printing means and the foil
together so as to sandwich the thermal transfer ribbon therebetween in a
constrained state,
means for moving the foil and the energizable printing means
relative to one another at a specific speed while pressing the energizable
printing means and the foil together and while energizing the energizable
printing means, and
means for moving the thermal transfer ribbon relative to the
energizable printing means at a reduced speed as compared to the specific
speed of the foil relative to the energizable printing means and consequent-
ly moving the thermal transfer ribbon relative to the foil for causing the
ink of the thermal transfer ribbon to be transferred at the specific locations
to the foil at specific areas thereof constituting the printing
so as to smear the ink of the thermal transfer ribbon at the specific
locations onto the foil through the motion of the thermal transfer ribbon
relative to the foil.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
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below detailed description of preferred embodiments of the present
invention are in accordance with a sixth aspect of the present invention
obtained by means of a thermal printer for producing a printing on the
surface of a foil in an ink transfer operation, comprising:
5 means for supplying the foil to the thermal printer,
a thermal transfer ribbon including an ink which is transferable
in the ink transfer operation at specific locations of the thermal transfer
ribbon by heating the specific locations to an elevated temperature causing
the ink to be fluid,
10 means for arranging the thermal transfer ribbon i facial contact
with the surface of the foil,
energizable printing means for heating the specific locations of
the thermal transfer ribbon to the elevated temperature in the ink transfer
operation,
means for energizing the energizable printing means,
means for pressing the energizable printing means and the foil
together so as to sandwich the thermal transfer ribbon therebetween in a
constrained state,
means for moving the foil and the energizable printing means
relative to one another at a specific speed while pressing the energizable
printing means and the foil together and while energizing the energizable
printing means, and
means for moving the thermal transfer ribbon relative to the
energizable printing means at a reduced speed as compared to the specific
speed of the foil relative to the energizable printing means and consequent-
ly moving the thermal transfer ribbon relative to the foil for causing the
ink of the thermal transfer ribbon to be transferred at the specific locations
to the foil at specific areas thereof constituting the printing the
energizable
printing means being stationary and the means for moving the foil and the
energizable printing means relative to one another causing the foil to move
relative to the energizable printing means in a continuous motion and the
means for moving the thermal transfer ribbon relative to the energizable
printing means moving the thermal transfer ribbon relative to the energiz-
able printing means at the reduced speed while the energizable printing
means are heated during the ink transfer operation and moving the thermal
transfer ribbon relative to the energizable printing means in the reverse
direction relative to the energizable printing means while the energizable
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printing means are not heating so as to utilize an unused part of the
thermal transfer ribbon in a subsequent ink transfer operation.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a seventh aspect of the present invention
obtained by means of a thermal printer for producing a printing on the
surface of a foil in an ink transfer operation, comprising:
means for supplying the foil to the thermal printer,
a thermal transfer ribbon including an ink which is transferable
in the ink transfer operation at specific locations of the thermal transfer
ribbon by heating the specific locations to an elevated temperature causing
the ink to be fluid,
_ _ means for arrange thermal transfer ribbon i facial contact
with the surface of the foil,
energizable printing means for heating the specific locations of
the thermal transfer ribbon to the elevated temperature in the ink transfer
operation,
means for energizing the energizable printing means,
means for pressing the energizable printing means and the foil
together so as to sandwich the thermal transfer ribbon therebetween in a
constrained state, '
means for moving the foil and the energizable printing means
relative to one another at a specific speed while pressing the energizable
printing means and the foil together and while energizing the energizable
printing means, and
means for moving the thermal transfer ribbon relative to the
energizable printing means at a reduced speed as compared to the specific
speed of the foil relative to the energizable printing means and consequent-
ly moving the thermal transfer ribbon relative to the foil for causing the
ink of the thermal transfer ribbon to be transferred at the specific locations
to the foil at specific areas thereof constituting the printing the means
for moving the foil and the energizable printing means relative to one
another causing the foil to move intermittently and maintaining the foil
stationary during the ink transfer operation and causing the energizabIe
printing means to move relative to the stationary foil and the means for
moving the thermal transfer ribbon relative to the energizable printing
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means moving the thermal transfer ribbon relative to the energizable
printing means at the reduced speed while the energizable printing means
are heated during the ink transfer operation and moving the thermal
transfer ribbon in the reverse direction relative to the energizable printing
means while the energizable printing means are not heated so as to utilize
an unused part of the thermal transfer ribbon in a subsequent ink transfer
operation.
The above objects and the above advantage together with numerous
other objects, advantages and features which will be evident from the
below detailed description of preferred embodiments of the present
invention are in accordance with a eighth aspect of the present invention
obtained by means of a thermal printer for producing a plurality of
individual printings on the surface of a foil in an ink transfer operation,
comprising:
means for supplying said foil to said thermal printer,
a thermal transfer ribbon defining a specific width along a trans-
versal.direction thereof each of said printings defining a maximum
dimension along a direction coinciding with said transversal direction
constituting no more than 50 % of said width and including an ink which is
transferable in said ink transfer operation at specific locations of said
thermal transfer ribbon by heating said specific locations to an elevated
temperature causing said ink to be fluid,
means for arranging said thermal transfer ribbon i facial contact
with said surface of said foil,
energizable printing means for heating said specific locations of
said thermal transfer ribbon to said elevated temperature in said ink
transfer operation,
means for energizing said energizable printing means,
means for pressing said energizable printing means and said foil
together so as to sandwich said thermal transfer ribbon therebetween in a
constrained state,
means for moving said foil and said energizable printing means
relative to one another at a specific speed
means for moving said thermal transfer ribbon relative to said
energizable printing means in said ink transfer operation while pressing
said energizable printing means and said foil together and while energizing
said energizable printing means causing said ink to be transferred to said
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foil at a first area thereof producing a first printing on said foil at one of
the longitudinal edges of said thermal transfer ribbon, and
said means for moving said thermal transfer ribbon relative to
said energizable printing means causing said thermal transfer ribbon to be
relocated relative to said energizable printing means while said energizable
printing means are not heated so as to utilize an unused part of said
thermal transfer ribbon.
The present invention is now to be further described with reference to
the drawings, in which
Fig. I is an overall perspective and schematic view of a first and
presently preferred embodiment of a printing apparatus according to the
present invention, illustrating a feature of saving thermo-transfer ribbon by
decelerating the thermo-transfer ribbon,
Fig. la is a part of a perspective and schematic view similar to the
view of Fig. 1 illustrating a further feature of saving thermal transfer
ribbon by side-shifting during the printing operation,
Fig. lb is a part of a perspective and schematic view similar to the
view of Fig. la illustrating a further feature of saving thermo-transfer
ribbon through retraction during the printing operation,
Fig. 2 is a perspective and schematic view of a printing assembly of
the first embodiment of the printing apparatus in a disassembled state
disclosing the interior of the printing assembly,
Fig. 3 is a perspective and schematic view of a part of the printing
assembly shown in Fig. 2, as the printing assembly is illustrated from the
opposites side as compared to the views of Figs. 1 and 2,
Fig. 4 is a schematic view illustrating the overall operation of the
printing apparatus illustrated in Fig. I,
Fig. Sa is a perspective and schematic view illustrating a printing
assembly of a further, or second, embodiment of the printing apparatus
according to the present invention, illustrating the feature also illustrated
in
Fig. 1 of saving thermo-transfer ribbon through decelerating the thermo-
transfer ribbon,
Fig. Sb is a perspective and schematic view similar to the view of Fig.
Sb illustrating the feature of saving thermo-transfer ribbon also illustrated
in Fig. Sa through side-shifting during the printing operation,
Fig. Sc is a perspective and schematic view similar to the views of
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- Figs. Sa and Sb illustrating the further feature of saving thermo-transfer
ribbon through retraction during the printing operation,
Fig. 6 is a perspective and schematic view similar to the view of fig. 6
of a still further, or third, embodiment of a printing apparatus according to
the present invention,
Fig. 7 is a block diagrammatic view of the electronic circuitry of the
first and presently preferred embodiment of the printing apparatus shown
in Fig. 1,
Figs. 8a-8c are diagrammatic views illustrating in greater details the
electronic circuitry of the first embodiment of the printing apparatus
shown in Fig. 1,
Figs. 9~-9q are flow charts illustrating a first mode of operation of the
first and presently preferred embodiment of the printing apparatus shown
in Fig. 1, and
Figs. l0a-lOv are flow charts illustrating a second mode of operation
of the first and presently preferred embodiment of the printing apparatus
shown in Fig. 1.
In Figs. 1-3, a first and presently preferred embodiment of a printing
apparatus implemented in accordance with the teachings of the present
invention is shown and designated the reference numeral 10 in its entirety.
The apparatus basically comprises two parts or section, a printing
assembly 12 to be described in greater detail below with reference to Figs.
2 and 3 and a control assembly or housing 14, the structure of which is
illustrated in Figs. 7 and 8a-8c, and the function of which for controlling
the overall operation of the printing apparatus 10 is illustrated in Figs. 9a-
9q.
The printing apparatus 10 is mounted in a frame, not shown in greater
detail, of a packaging apparatus or similar apparatus in which a continuous
foil 16 is to be applied with a large number of printings. The foil 16 may
constitute any appropriate foil of a material allowing the printing of a
number of prints by means of a heat transfer foil, such as conventional
polymer foil materials used in the packaging industry or for packaging
purposes. Examples of relevant foil materials are PE, PVC, PP of woven
or non-woven structure and organic fibre materials, such as paper
materials or combined paper and polymer foil materials. The foil 16 is
supplied from a foil supply reel 18 mounted on a stationary shaft 20 and
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guided round two rollers 22 and 24 of the packaging apparatus, which
rollers define a substantially horizontal path of travel of the foil 16. The
printing assembly 12 is positioned above the roller 24 and establishes the
printing of the printings on the foil 16 as the foil 16 passes by the roller
24
5 in its continuous high-speed motion. It is in this context to be realized
that
the foil 16 may be travelling at a speed of several hundred mm/s, such as a
speed of 2-300 mm/s, or even more.
It is further to be realized that the orientation of the foil 16 and the
orientation of the printing apparatus as illustrated in Fig. 10 is by no
10 means mandatory in relation to the teachings of the present invention as
the foil 16 may travel along a path differing from the horizontal, or
substantially horizontal, path of travel illustrated in Fig. 1, such as a
sloping or a vertical path of travel, and similarly, the printing apparatus 10
may be mounted or arranged so as to apply printings on the foil of an
15 orientation differing from the horizontal, or substantially horizontal,
From the roller 24, the foil 16 to which printings 26 are applied, as
will be described in greater detail below, travels on and is guided below a
further roller 28. The rollers 22, 24 and 28 all constitute idler rollers and
the foil I6 is caused to travel by means of a drive roller 30 which
cooperates with a capstan roller 32. The drive roller 30 is caused to rotate
defining a peripheral speed of travel corresponding to the speed of travel
of the foil 16 by means of a motor 34 which is connected to the roller
through a gear assembly 38. The motor 34 may constitute any AC or DC
motor, the operation and speed of which may be controlled by means of an
external motor controller, not shown in the drawings. The drive motor 34
receives electric power through a power supply cord 36 from an external
power supply source being an AC or DC power supply source. The
capstan roller 32 cooperates with the drive roller 30 for causing the foil 16
to move as the capstan roller 32 contacts the outer surface of the roller 30
and causes the foil 16 to move as is well-known in the art per se.
The idler rollers 22 and 28 and the capstan roller 32 are made from
steel, whereas the drive roller 30 is a roller provided with an elastomeric
outer surface, such as a rubber surface which may be slightly deformed
through contact with the capstan roller 32. The drive roller 24 is also
provided with an elastomeric outer surface constituting a soft deformable
surface, such as a Teflon surface, providing a counter surface during a
printing operation.
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16
The rotational motion of the foil 16 is detected by the control assembly
14 of the printing apparatus 10 by means of a detector or encoder 40
which supplies an electric control or encoder signal to the control
assembly 14 through a signal wire 42. The detector or encoder 40 may be
constituted by a contact or non-contact detector or encoder based on
inductive, capacitive or optic detecting principles well-known in the art per
se. In the embodiment illustrated in fig. 1, the detector or encoder 40 is
constituted as a contact encoder which comprises a rotating wheel 44
which transfers the rotational motion of the roller 30 to an optic detector
46 for generating pulses representing the rotational motion of the drive
roller 30 and consequently the motional travel of the foil I6.
For operating the printing mechanism of the printing assembly 12, the
printing apparatus 10 receives pressurized air from an external pressurized
air source through a supply tubing 48 and through a pressurized air valve
50 which controls the supply of pressurized air to the printing apparatus 10
through a pressurized air inlet tube 52. The pressurized air valve 50
receives a signal from the control assembly 14 through an electric wire,
not shown in the drawings. The function of the pressurized air supply will
be evident from the below discussion of the structure and function of the
printing assembly 12. The printing assembly 12 is composed of two
parallel plate or wall elements 54 and 56 which are kept in spaced-apart
relationship by means of distance elements, including a hollow element 58,
and by means of a locking element which is operated by means of a
locking lever 60 shown in Fig. 1 in solid line in its locked position and
shown in Fig. 1 in its unlocked or released position. The locking position
of the locking lever 60 is defined by a pin 62 and the unlocked position or
released position of the locker lever 60 is defined by a further pin 64. The
plate element 54 constitutes a rear plate or rear wall supporting a solenoid-
actuated pressurized air supply valve to be described below and
supported on a bracket 66. The plate element 56 constitutes a front plate or
front wall supporting a handle 68 by means of which the front plate 56 and
the components and elements supported on the front plate 56 may be held
when the front plate 56 is separated from the rear plate 54, as is illustrated
in Fig. 2, provided the locker lever 60 is in the unlocked or released
position shown in dotted line in Fig. 1. The handle 68 is in Fig. 1
illustrated in a recessed position and in Fig. 2 shown in an extracted
position, allowing the handle 68 to be used for gripping and holding the
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17
front wall 56.
Within the inner-space defined between the rear plate 54 and the front
plate 56, a heat-transfer ribbon is moved in an intermittent motion
controlled by the controller assembly 14 for establishing the printings 26
on the foil 16. The various elements of the printing mechanism received
within the inner-space defined between the rear wall 54 and front wall 56
will be described below with reference to Fig. 2. The terms "inner" and
"outer" and equivalent terms are used in the present context referring to
the inner space defined between the rear wall 54 and front wall 56.
The controller assembly 14 is housed within a housing 70 which
defines a front plate 72 in which a display 74 is provided together with a
number of keys 76 for programming and operating the controller assembly
14 and the printing apparatus 10 along with a number of control lamps 78
and display elements 80 which serves the purpose of presenting
information to the operator concerning the programming of the controller
assembly 14, and also the operation of the overall printing apparatus 10.
The various keys, lamps and display elements 80 are not to be described in
greater detail, as these elements may be configured and implemented in
accordance with specific requirements, or alternatively may be eliminated
provided the printing apparatus is configured so as to perform one single
preset and specific printing operation which is addressed or controlled and
monitored by an external source, such as a remote PC-based controller.
In fig. 2, the inner-space defined within the rear plate 54 and the front
plate 56 is revealed, disclosing the components of the printing mechanism
contained within said inner-space. The rear plate 54 supports, as stated
above, the tubular element 58 which serves the purpose of receiving and
arresting a pin element 82 supported by and protruding inwardly from the
front plate 56. A further pin element 84 is provided protruding inwardly
from the front plate 56. The pin element 84 is adapted to be received
within a bore 86 of a block 88 which is rigidly connected to the rear wall
55 and includes a recess for receiving an arm 90 which is journalled
pivotally relative to the block 88, and consequently the rear wall 54, on an
inner shaft of the block 88. The arm 90 supports at its outer distal end a
printing head 100 and may be raised and lowered during the process of
disassembling and assembling the printing assembly 10 for allowing easy
access to the interior of the printing assembly as the arm 90 is biased
towards its raised position shown in Fig. 2 by means of a spring included
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within the block 88.
Apart from the pin elements 82 and 84, four additional pins 92, 94, 96
98 and 99 protrude inwardly from the front plate 56, serving the purpose
of maintaining the front plate in a specific spaced-apart relationship
relative to the rear wall 54 as the pin elements 82 and 84 are received
within the bores of the block 88 and the tubular element 58, respectively,
provided the front plate 56 is locked in its locked position as the locking
lever 60 is in the position illustrated in solid line in Fig. 1.
The locking lever 60 cooperates with a locking pin 102 which at its
outer distal end is provided with a transverse minor pin 104. As the front
plate 56 is positioned juxtaposed the rear plate 54 as the pins 82 and 84 are
received within the respective bores of the block 88 and the tubular
element 58, respectively, and kept in its intentional spaced-apart
relationship relative to the rear wall 54, the locking pin 102 is received
within an inner bore 106 of a locking element 108 which is journalled on a
rotating shaft 110 supported by the rear wall 54 and which is provided
with outwardly extending wing elements 114 and 116. On the rotating
shaft 110, a cam element 112 is mounted for cooperating with the outer
distal end of the arm 90. As the locking lever 60 is rotated from its
unlocked position shown in dotted lines in Fig. 1 to its locked position
shown in solid line in Fig. 1, the transverse pin 104 of the locking pin 102
causes through its cooperation with the locking element 108 the shaft 110
to rotate in its counter-clockwise direction, causing the cam 112 to be
lowered and rotated 900 in the counter-clockwise direction urging the
outer distal end of the arm 90 downwardly, causing the printing head 100
to be lowered. Similarly, when the locking lever 60 is rotated from its
locked position shown in solid line in Fig. 1 to its unlocked position shown
in dotted lines in Fig. 1, the arm 90 is raised as the cam 112 is rotated
clockwise from its lowered position, not shown in fig. 2, to the position
shown in Fig. 2.
The locking of the front plate 56 relative to the rear plate 54 is
established as the element 106 is rotated 900 counter-clockwise from its
position shown in fig. 2, causing the outwardly extending wing elements
114 and 116 to be locked and arrested behind locking brackets 118 and
120 supported by the front wall 56. The front wall 56 further supports an
inwardly protruding shaft 122 on which a thermo-printing ribbon reel 124
is received and supported from which a thermo-printing ribbon 130 is
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19
supplied. The thermo-printing ribbon 130 is delivered from the reel 124 as
the reel 124 is rotated on the shaft 122, still, the rotation of the reel 124
relative to the shaft 122 is controlled through a braking spring 126 serving
the purpose of preventing that the ribbon 130 is freely delivered from the
reel 124 in a non-tensioned mode. Furthermore, a rotably mounted
tensioning pin 86 is provided which is mounted on a rotating arm 87 for
catching up any slack in the ribbon 130 and for collecting a length of the
ribbon 130 delivered from the reel 124. The tensioning pin 86 is spring-
biased in the counterwise direction and is of importance not only as far as
compensating for any ribbon material delivered from the reel 124, but also
for allowing the printing apparatus to reverse the direction of movement of
the ribbon 130 relative to the printing head 100 in certain operations to be
described below and referred to as "side shift technique" and "retraction
technique" to be described below with reference to Figs. la and lb. The
ribbon 130 is guided round the distance pins 92, 94, 96 and 98 def ring a
lower horizontal path which is kept substantially parallel to the path of
travel of the foil 16 when the printing assembly 12 is in the assembled
state illustrated in Fig. 1. From the distance pin 98, the ribbon 130 is
guided around a drive roller 128 which is driven by a motor assembly
supported by the rear wall 54 and further guided from the drive roller 128
round the distance pin 99 and collected on a take-up reel 132. The take-up
reel 132 is connected to the drive roller 128 through a belt drive
mechanism including a toothed belt 134 which is driven by a drive gear
wheel 136 of the drive shaft 128 and further cooperates with a gear wheel
138 of the take-up reel 132, which gear wheel 138 is connected to the
take-up reel 132 through a frictional clutch compensating for the change of
diameter of the take-up reel 132 as the ribbon 130 is collected on the take-
up reel 132 in the transmission of the rotation of the drive shaft 128 to the
take-up reel I32.
The inner side of the rear wall 54 is illustrated in the upper left-hand
part of Fig. 2 and the outer side of the rear wall 54 is illustrated in Fig.
3.
The rear wall 54 supports a motor assembly for actuating the drive roller
128 of the front plate 56, which motor assembly includes a motor 140
arranged at the outer side of the rear plate 54 and protruding outwardly
relative thereto. The motor 140 has its output shaft extending through the
rear plate 54 and connected to a drive pulley 142 positioned at the inner
side of the front plate 54, which drive pulley 142 cooperates with a belt
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144 cooperating with a drive shaft 146 which is journalled on a journalling
bearing 148 and protrudes inwardly into the inner space defined within the
printing assembly 112 and cooperates with the drive roller 128 as the drive
shaft 146 is received within the drive roller 128 when the front wall 56 is
5 received and locked in position relative to the rear plate 54.
The motor assembly further includes a tensioning pulley 149 which
serves the purpose of establishing a preset and specific tensioning of the
drive belt 144. As will be understood, the rotational motion of the output
shaft of the motor 140 is transmitted through the drive pulley 142, the belt
10 144 and the drive shaft 146 to the drive roller 128 when the front plate 56
is positioned and locked relative to the rear plate 54 as described above.
In Fig. 3, a printed circuit board 150 is shown, including the motor
control electronics for controlling the function and operation of the motor
140. The printed circuit board 150 is connected to the controller assembly
15 14 through two multicore cables 152 and 154 and is connected to the
- motor 140, and optionally detectors of the printing assembly for detecting
- whether or not the front plate 56 is properly positioned and locked relative
to the rear plate 54. In the below description of the electronic circuitry of
the printing apparatus 10, a detector 180, not shown in Fig. 2, is described
20 serving the above purpose. As is evident from Figs. 2 and 3, a further
multicore cable 156 is provided for establishing connection between the
printing head 100 and the control assembly 14.
The arm 90 is, as discussed above, caused to be raised through the
biasing from the bias spring contained within the block 88 to its raised
position shown in fig. 2, provided the cam 112 is in its raised position also
shown in Fig. 2. As the shaft 110 is rotated 900 clockwise, the cam 112
forces the arm 90 downwardly, positioning the printing head 100 in its
stand-by position ready for performing a printing function.
The outer end of the arm 90 is provided with a printing head
suspension block 160 in which the printing head 100 is suspended
pivotally. The printing head 100 is journalled pivotally relative to the
suspension block 160 by means of a rotating shaft 162 and is urged to a
raised position by means of a biasing spring 164, forcing the printing head
100 to be raised or lifted upwardly relative to the foil 16 in its stand-by
mode. When a printing operation is to be performed, the printing head 100
is lowered as the pressurized air supplied to the printing assembly 12
through the pressurized air-inlet tube 52 is further supplied to a pneumatic'
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21
actuator valve 166 through a pressurized air supply hose 168 from a
solenoid-actuated pressurized air supply valve 170 mounted on the outer
side of the rear wall 54 and connected to the motor controller circuit board
150 through an electric wire 172.
Before turning to a specific description of the printing operation to be
performed by means of the printing apparatus 10 described above with
reference to Figs. 1-3, and also with reference to Fig. 4, it is to be
realized that the printing head 100 is a thermo-transfer printing head
including a number of transversly spaced-apart heating elements, such as
ten heating elements per mm, or even more heating elements, allowing a
specific point-like area of the lower exposed surface of the printing head to
be heated by heating a specific heating element. The printing head 100 is
in itself a component well-known in the art per se and readily available
from numerous manufacturers, such as the Japanese manufacturer
Kyocera. The printing head may be of any specific transverse dimension,
such as a 1 inch, 2 inch width, or even wider. Also in a modified
embodiment, a plurality of printing heads may be mounted on a common
operational shaft, allowing a wider ribbon to be used for producing even
wider printings in excess of 2 inch, e.g. of any arbitrary width, e.g. an
integer multiple of 1 or 2 inches.
The printing operation is performed as follows. The control assembly
14 is pre-programmed locally or remotely through an external in/out port
from a remote computer, such as a remote PC, for producing a print of a
specific typographic shape and also of a specific spacing on the foil 16. It
is to be realized that the computerized controlling of the printing apparatus
10 allows the printing apparatus to produce individual prints on the foil 16,
such as prints of a consecutive numbering, including individual data or
identifications of any arbitrary kind, such as a production number, a time
of date, etc. , without in any way changing the overall function of the
printing apparatus. The foil 16 is caused to travel along its substantially
horizontal path between the rollers 22 and 24, vide Fig. 4, at a speed of
travel of V2 up to 500 mm/s, driven by the motor 34 and the drive roller
30 as discussed and described above. The motion of the foil 16 is detected
by means of the motion sensor or detector 40. Provided the printing
assembly 12 is properly assembled, which is detected by means of the
above-mentioned detector 180 preferably cooperating with the locking
lever 60, the control assembly 14 controls the pressure valve 50 to open
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22
for the supply of pressurized air to the solenoid-actuated valve 170. As the
control assembly 14 detects the motion of the foil 16 and on the basis of its
programme establishes that a printing is to be performed, the motor 140 of
the motor assembly is energized for causing the ribbon 130 to move in
parallel with the foil 16 and at the same time energizes the solenoid-
actuated valve 170, causing the printing head 100 to be forced downwardly
towards the counter roller 24 for pressing the ribbon 130 into contact with
the surface of the foil 16. The specific heating elements of the printing
head 100 is addressed in conformity with the printing to be made for
heating specific areas of the thermo-transfer ribbon 130 for causing the ink
of the thermo-transfer ribbon to be heated to an elevated temperature
allowing the ink to be transferred to the foil 16 as the ribbon 130 is
pressed or squeezed against the foil 16. According to the teachings of the
present invention, the ribbon 130 is moved at a lower speed V 1 as
compared to the speed of travel of the foil 16 on the one hand providing a
perfectly readable printing and at the same time saving ribbon material as
compared to a printing operation i which the thermo-transfer ribbon 130 is
moved in synchronism with the foil 16.
It has, surprisingly, been realized that the technique of reducing the
speed of the thermo-transfer ribbon 130 relative to the foil 16 does not
deteriorate the quality of the printing which is believed to be caused by the
fact that the process of transferring ink from the heated areas of the
thermo-transfer ribbon 130 to the foil 16 may be considered as a smearing
process rather than a contact printing process, which smearing process
smears the heated ink onto the foil rather than simply transferring the ink
through facial contact between the thermo-transfer ribbon 130 and the foil
16. The speed of motion of the thermo-transfer ribbon 30 is controlled by
the control assembly 14 and according to the teachings of the present
invention it has been realized that the speed of motion V 1 of the thermo-
transfer foil 130 may be reduced to even 20-30 % of the speed of motion of
the foil 16. Also, according to the teachings of the present invention, it has
surprisingly been realized that an improved printing, as compared to a
printing process in which the velocities V 1 and V2 are identical, is
obtained, provided the velocity V 1 is reduced to 95-97 % of the speed V2
which is believed to be originating from the above described smearing
effect.
It has, furthermore, surprisingly been realized that further thermal-
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23
transfer ribbon material may be saved during the printing operation
through further techniques which are illustrated in Fig. la and lb and
relate to side-shifting the printings during the printing operation and
retraction of the thermal-transfer. ribbon during the printing operation, re-
spectively.
In fig. la, a printing 26a is to be produced on the foil 16 which
printing defines a width perpendicular to the longitudinal direction of the
foil 16 constituting only a fraction and in particular less than 50% of the
width of the foil 16. In numerous instances, the specific location of the
printings on the foil 16 are of minor relevance, e. g. provided the printings
constitute printings representing the date of packaging the material or
printings identifying the packaging machine or any other identify, in which
instance the printings such as the printing 26a illustrated in fig. la need
not to be positioned as a specific location on the foil 16 allowing that the
printing 26a be shifted sidewise during the printing operation allowing the
entire width of the thermo-transfer ribbon 130 to be utilized. As an
example, assuming the width of the printing 26a constitutes less than 20
of the total width of the foil 16, a first printing 26a is produced adjacent
to
one of the edges of the foil 16 whereupon the next printing is produced
shifted one fifth of the width of the foil 16 sidewise and so on for the next
three printings allowing a total of five prints to be produced sidewise
shifted along the foil 16 still utilizing no more than a single peace of
thermo-transfer ribbon material corresponding to a single thereby
producing a total saving of 80 % of the thermo-transfer ribbon material as
compared to a conventional thermo-transfer printer or a thermo-transfer
printer operated in accordance with the technique of reducing the speed of
the thermo-transfer ribbon relative to the foil as discussed above with
reference to Fig. 1. Consequently, through combining the speed reduction
technique described above with reference to Fig. 1 and further the side-
way shifting technique illustrated in Fig. la and discussed above, an
extreme saving of thermo-transfer ribbon material may be obtained
provided the printings to be applied to the foil 16 constitute only a fraction
of the width of the foil material and provided it is acceptable to shift the
printings sidewise along the foil 16. Assuming that e.g. 50% material is
saved through the speed reduction technique described above, and
assuming that a total of e.g. five prints may be produced side by side on
the foil in the above described side-shifting operation, the amount of
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24
thermo-transfer ribbon material used in a printing process combining the
speed reduction technique and the side-shift technique allows that only
% of the thermo-transfer ribbon material be used in the apparatus
according to the present invention as compared to a conventional non-
_ 5 speed reducing and non-side-shifting apparatus producing the same
pnntmgs.
It has still further surprisingly been realized that a saving of thermo-
transfer ribbon material may be obtained provided the direction or
- movement of the thermo-transfer ribbon be reversed during the printing
10 operation or between any two printing operations for retraction of the
thermo-transfer ribbon providing the printings to be produced define a
configuration having outer contours allowing any two adjacent printings to
be positioned in closely juxtaposed position. In Fig. lb, this technique of
saving thermo-transfer ribbon material through reversing the direction or
motion of the thermo-transfer ribbon or retraction of the thermo-transfer
ribbon after the completion of a single printing operation is illustrated. In
Fig. lb, the printings to be produced on the foil 16 is a printing of an
overall configuration of a Z having two wings protruding in opposite
directions along the longitudinal direction of the foil 1. Provided the
thermo-transfer ribbon 130 is not reversed for retraction of the thermo-
transfer ribbon, the leading edge of the Z printing 26b would be initiated
at a location of the thermo-transfer ribbon 30 in spaced apart relationship
from the area used for the previous printing as the new printing would be
produced by the utilization of thermo-transfer ribbon material starting
from the end of the material previously used for the previous printing. By
the retraction of the thermo-transfer ribbon, the starting point for the new
printing may be located within an area of the thermal-transfer ribbon
material which was unused for the previous printing and which may still
be utilized in the new printing without producing overlaps between the
areas used during the two printing operations on the thermal-transfer
ribbon 130.
The retraction technique illustrated in Fig. lb may in certain instances
be combined with the side-shifting technique illustrated described above
with reference to Fig. la and may advantageously with or without the
combination with the side-shifting technique be combined with the speed
reduction technique described above with reference to Fig. 1.
The above described first and presently' preferred embodiment of the
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- printing apparatus 10 according to the present invention performs its
- printing operation in an orientation or direction co-extensive with the
direction of travel of the continuously moving foil 16 to which the
printings are to be applied. The teachings of the present invention,
5 however, may also advantageously be utilized in connection with printing
apparatuses which operate in connection with intermittently moving foils
and perform their printing operations along a direction of orientation
transversly relative to the direction of motion of the foil. In Figs. Sa and
6, two alternative embodiments of printing assemblies are shown
10 schematically for producing printings in a direction transversly relative
to .
the direction of travel of the foil to which the printings are to be applied.
In Figs. Sa and 6, elements or components identical to elements or
components described above with reference to Figs. 1-4 are designated the
- same reference numerals;whereas elements or components similar to or
15 serving the same purpose as elements described above with reference to
Figs. 1-4 are designated the same figure, however, added the marking ' in
Fig. Sa and the marking " in Fig. 6.
The printing assembly 12' shown in Fig. Sa includes a further motor
assembly including a motor 190 for causing the printing head 100 to be
20 moved from a left-hand position transversly to a right-hand position
relative to the foil 16' . The printing head 100 is in Fig. Sa shown in its
stand-by position. The motor 190 cooperates with the printing head
through a drive pulley 192 mounted on the output shaft of the motor 190, a
belt 194 and a pulley 196 journalled on a supporting slide, not shown in
25 Fig. Sa, on which the printing head 100 is mounted, allowing the printing
head to be raised and lowered as described above with reference to Fig. 2.
The thermo-transfer ribbon 130 is moved in its overall direction of motion
as indicated by an arrow 200 and supplied from the ribbon supply reel 124
to the ribbon take-up reel 132. Contrary to the above described first
embodiment, the supply reel 124 is also motorized as the printing
assembly includes an additional motor assembly and a further drive roller
198 corresponding to the drive roller 128, a further belt 202 corresponding
to the belt 134, and also a further cam gear wheel 204 and a gear wheel
206 including a frictional clutch corresponding to the drive gear wheel 136
and the gear wheel 138 described above with reference to Fig. 2.
The printing assembly 12' is operated in the following manner. As the
foil 16' is kept stationary, the printing head 100 is forced into contact with
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26
the upper side of the thermo-transfer ribbon 130 and moved from its left-
hand position shown in Fig. Sa to its right-hand position and at the same
time the thermo-transfer ribbon 30 is reversed and moved at a lower speed
as compared to the speed of motion of the printing head 100. After the
printing operation has been performed, the printing head 100 is raised in
its right-hand position and reverts to its stand-by position shown in Fig.
Sa, and the foil 16' is intermittently moved one further step and at the
same time, the thermo-transfer foil 130 is moved in the direction indicated
by the arrow 200 for collecting the used thermo-ribbon material on the reel
130 and positioning unused thermo-transfer ribbon material for the next
printing operation.
The second embodiment of the printing apparatus illustrated in Fig. Sa
may further advantageously be used for the above described side shifting
andlor the above described retraction technique as is illustrated in Fig. Sb
and Sc, respectively, allowing the further saving of thermo-transfer ribbon
material. In Fig. Sb, the side shifting technique is illustrated as three
identical printings 26' b are produced side-shifted relative to one another
still produced without lengthwise shifting the thermo-transfer ribbon 130'
along the direction of the arrow 200 or in the opposite direction as the
areas of the thermo-transfer ribbon material 130' used for these three side-
shifted printings 26'b are positioned adjacent one another.
In fig. Sc, the retraction technique by utilizing or employing the second
embodiment of the printing assembly illustrated in Figs. Sa and Sb is
disclosed as a printing 26 is produced involving the above described
retraction technique in combination with the speed reduction technique
described above with reference to Fig. Sa. The two neighbouring printings
26'c are produced by utilizing mutually overlapping areas of the thermo-
transfer ribbon 130' by shifting or retraction of the thermo-transfer ribbon
130' in the direction opposite to the arrow 200 after the completion of a
first printing operation and before the initiation of a second printing
operation.
In Fig. 6, a modified third embodiment of the printing assembly
illustrated in Fig. Sa is shown designated the reference numeral 12" . The
third embodiment 12" basically differs from the above described second
embodiment 12" in that the above described further motor assembly for
producing a motorized supply reel 124 is eliminated as the thermo-transfer
ribbon 130 is moved in one and the same direction during the printing
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27
operation, also producing the take-up on the take-up reel 132 of the
thermo-transfer ribbon material without necessitating any reversal of the
direction of motion of the thermo-transfer ribbon 130. In Fig. 6, the
direction of motion of the thermo-transfer foil is indicated by an arrow
208, which direction of motion is parallel to and unidirectional relative to
the direction of motion of the printing head 100 during the printing
operation, providing an overall simplified structure as compared to the
structure illustrated in Fig. Sa.
The third embodiment of the printing assembly illustrated in Fig. 6
may also be used for utilizing the side-shifting and retraction technique
described above with reference to Figs. lb and lc, respectively, and
further with reference to Figs. Sb and Sc, respectively.
In Figs. Sa and 6, the thermo-transfer ribbon saving aspect of the
present invention is illustrated as the width, i.e. the dimension of the
printings 26' and 26" produced on the foils 16' and 16" in Figs. Sa and 6,
respectively, is larger than the corresponding width of the signatures
produced on the thermo-transfer ribbons 130' and 130" . Similarly, in Fig.
1, the lengthwise or longitudinal extension of the printing 26 is substantial-
ly larger than the corresponding extension of the signature produced on the
thermo-transfer ribbon 130.
In Figs. la and Sb, the thermo-transfer ribbon saving aspect of the
present invention through utilizing the above described side-shifting
technique is illustrated as the signatures produced on the thermo-transfer
ribbons I30 and 130' for producing the side-wise shifted printings are
located adjacent one another covering the entire width of the thermo-
transfer ribbon. Similarly, in Figs. lb and Sc, the thermo-transfer ribbon
saving aspect by utilizing the retraction technique is illustrated as the
signatures produced on the thermo-transfer ribbons for producing the
printings 26c and 26'c, respectively, are fitted into one another rather than
located within separate areas of the respective thermo-transfer ribbons.
In Fig. 7, the electronic circuitry of the printing apparatus described
above with reference to Figs. 1-4 is shown in block diagrammatic view.
The electronic circuitry includes centrally a CPU-board 220
communicating with a controller board 222 and also communicating with a
power supply block 224. The power supply block receives electric power
from a transformer 226 which is further connected to the mains supply,
i.e. a 115 V, 60 Hz or a 230 V, 50 Hz mains supply. The electronic
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28
circuitry further includes blocks identifying the printer head 100, the
display 74, a PCMCIA card station block 228, a serial and parallel port
block 230 and the keyboard 76.
These blocks all communicate with the CPU board 220. Similarly, the
controller board 222 communicates with a block constituting the display
74, the indicators and lamps 78 and 80, respectively, and also the detector
180. The controller board 222 communicates with the above described
peripheral element illustrated by a block identifying the foil motion
detector or encoder 40, the solenoid 170 for actuating the printing head
IO 100 and the control circuit 150 for controlling the motor 140. An
additional block 232 is provided for establishing communication to an
external detector concerning the state of operation of the packaging
machine or for controlling the shift of printing from one specific print to
another alternative printing, or for modifying the printing on any arbitrary
basis, such as a counter-based modification, a time-based modification, or
even a modification of the printing based on an external input entity.
In Figs. 8a-8c, the electronic circuitry of the printing apparatus 10 is
illustrated in greater detail. The circuit diagrams are believed to be self
explanatory and no detailed discussion of the electronic circuitry is
presented as the diagrams solely serve the purpose of illustrating the
presently preferred implementation or embodiment of the electronic
circuitry of the first and presently preferred embodiment of the printing
apparatus 10 according to the present invention. Fig. 8a illustrates the
power supply block 224, Fig. 8b illustrates the electronic circuitry of the
controller board 22, Fig. 8c illustrates the electronic circuitry of the motor
driver circuitry included in the electronic circuit board 150.
Example
The electronic circuitry of the above described first and presently
preferred embodiment of the printing apparatus according to the present
invention was implemented in a prototype embodiment as follows,
including the components identified in Figs. 8a-8c.
The transformer block 226 included a 230 V/32 V transformer. The
power supply block 224 included a rectifier for rectifying 32 V AC to 46
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29
V DC and further three switch mode regulators of the type LM2576 for
producing two 24 V DC and one 5 V DC supply outputs. One of the 24 V
DC outputs was amplified by a transistor for providing a 10 A output
current capacity. The step motor driver circuit included in the printed
circuit board 150 was supplied by the 46 V DC, the solenoid circuits were
supplied by 24 V and the CPU analogical circuits were supplied by 5 V
DC. The printing head was a 2 inch (51,2 mm) comer edge printing head
of the type Delta V2.00 supplied from the Japanese company Kyocera.
The display 74 was of the type md1s24265-lv-1ed04 including two times 24
characters. The PCMCIA station was adapted to operate on two boards of
the type sram from 256 Kbyte to 2 Mbyte. The serial and parallel ports
were constituted by a parallel standard centronic parallel port, and a serial
standard RS232 serial port, respectively, adapted for 2400 baud to 19200
baud operation.
The keyboard 74 was a softkey keyboard including a numeric keyboard
also including directional arrow keys for programming the printing
apparatus. The CPU board 220 was a conventional label printer printing
board, however, including modified software for complying with the
requirements of the printing apparatus. The CPU board was connected as
described above to the blocks and elements illustrated in Fig. 7. The
controller board block 222 was configured around an Atmel 89C52 chip
and connected as and configured and interconnected to the various blocks
and elements illustrated in Fig. 7. The motor 140 was a Vexta PH266-
E1.2, 200 steps per revolution step motor. The motor driver circuit was
constituted by a step motor driver circuit implemented by PBM3960 and
PBL3770 integrated circuits supplied from Ericsson Electronics and was
further implemented in accordance with the electronic circuit illustrated in
Fig. 8c.
In Figs. 9a-9q, a first mode of the operation of the printing apparatus
10 described above with reference to Figs. 1-4 is illustrated in an overall
flow chart illustrated in Figs. 9a and 9b and individual sub-flow charts
illustrated in Figs. 9d-9q. The flow charts are believed to be self
explanatory and no detailed discussion of the flow charts is being
presented, apart from the below listing of the various sub-flow charts
illustrated in Figs. 9d-9q:
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Fig. 9c illustrates Segment 1 of the overall flow chart of Figs. 9a and 9b,
Set printer.
Fig. 9d illustrates Segment 2, Foil tension.
5
Fig. 9e illustrates Segment 3, Printer closed.
Fig. 9f illustrates Segment 4, Set printer stand-by.
10 Fig. 9g illustrates Segment 5, Stand-by.
Fig. 9h illustrates Segment 6, Printer ready continuous.
Fig. 9i illustrates Segment 7, Printer ready.
Fig. 9j illustrates Segment 8, Blink stand-by.
Fig. 9k illustrates Segment 9, Relative speed adjust.
Fig. 91 illustrates Segment 10, Encoder interrupt.
Fig. 9m illustrates Segment 11, Step motor interrupt.
Fig. 9n illustrates Segment 12, Pause.
Fig. 9o illustrates Segment 13, Set printer ready.
Fig. 9p illustrates Segment 14, Set-up div.
Fig. 9q illustrates Segment 15, One relative step.
In Figs. l0a-lOv a second mode operation of the printing apparatus 10
described above with reference to Figs. 1-4 is illustrated in an overall flow
chart illustrated in Figs. l0a and lOb and in individual sub-flow charts
illustrated in Figs. lOd-lOv. Like the above described flow charts
illustrated in Figs. 9a-9q, the flow charts illustrated in Figs. l0a-lOv are
believed to be self explanatory and no detailed discussion of the flow
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31
charts
is
being
presented,
apart
from
the
below
listing
of
the
various
sub-
flow
charts
illustrated
in
Figs.
lOd-lOv:
Fig. lOc illustrates Segment 1 of the overall flow chart
of Figs. l0a and
lOb, Set printer up. - -
Fig. lOd illustrates Segment 2, Foil tension.
Fig. l0e illustrates Segment 3, Printer closed. -
Fig. lOf illustrates Segment 4, Set printer stand-by.
Fig. lOg illustrates Segment 5, Stand-by.
Fig. lOh illustrates Segment 6, Printer ready continuous.
Fig. l0i illustrates Segment 7, Printer ready.
Fig. lOj illustrates Segment 8, Blink stand-by.
Fig. lOk illustrates Segment 9, Relative speed adjust.
Fig. 101 illustrates Segment 10, Modify retraction length.
Fig. lOm illustrates Segment 11, Column mode ON-OFF.
Fig. lOn illustrates Segment 12, Encoder interrupt.
Fig. loo illustrates Segment 13, Stepmotor interrupt.
Fig. lOp illustrates Segment 14, Pause.
Fig. lOq illustrates Segment 15, Set printer ready.
Fig. lOr illustrates Segment 16, Setup div.
Fig. lOs illustrates Segment 17, One relative step.
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Fig. lOt illustrates Segment 18, Move to head down.
Fig. l0u illustrates Segment 19, Foil retraction.
Fig. lOv illustrates Segment 20, Column mode foil retraction.
The above flow charts illustrating the mode of operation of the printing
apparatus may of course be modified in numerous ways through
elimination of a specific sub-flow chart corresponding to a specific
operation oar through combining the sub-flow charts illustrated in Figs. 9a-
9q with one or more of the sub-flow charts illustrated in Figs. lOc-lOv or
vice versa corresponding-to-rne combination of specific operations
illustrated in Fig. 9 with specific illustrations illustrated in Fig. 10 or
vice
versa.
Like the possible combination of the various routines of the modes of
operation illustrated in Figs. 9a-9q and in Figs. l0a-lOv, the above
described embodiments may of course also be modified through the
elimination of specific elements provided a specific embodiment is to be
implemented allowing only specific individual routines of the overall mode
of operation illustrated in Figs. 9a and 9q and in Figs: l0a and lOv or
alternatively, the above described embodiments may be combined through
combining elements from the second or third embodiment illustrated in
Figs. Sa-Sc and Fig. 6, respectively, with the first embodiment illustrated
in Figs. 1-4 or alternatively combining elements from the first embodiment
illustrated in Figs. 1-4 with the second or third embodiment illustrated in
Figs. Sa-Sc and Fig. 6, respectively. Of course, the second or third
embodiments illustrated in Figs. Sa-Sc and Fig. 6 may also be combined in
numerous ways obvious to a person having ordinary skill in the art for
deducing a specific printing apparatus complying with specific
requirements as to fulfilling certain operational requirements.
Although the present invention has been described above with
reference to different, presently preferred embodiments of the apparatus
and the method of producing printings by the thermo-transfer technique as
discussed above, the invention is by no means to be construed limited to
the above described embodiments, as numerous modifications are
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deduceable by a person having ordinary skill in the art, without still
deviating from the spirit and aim of the present invention as defined in the
appending claims.
S
