Note: Descriptions are shown in the official language in which they were submitted.
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AN INK JET RECORDING APPARATUS
FIELD OF THE lNV~N'l'lON AND RELATED ART
The present invention relates to an ink jet
recording apparatus for effecting recording by ejecting
ink to a recording materlal.
In the ink ~et re~cording apparatus, ink is
ejected through~ejection outlets of~a~recording~head
onto a recording material. ;The ink jet recording
apparatus has~the advantages that fine images can be
formed at a high speed,~the apparatus is not noisy
because it is of a non-impact type, and that it is
asy to record a color image using ink materials having
different colors.
~ 15In the ink iet recording apparatus, a
;~replaceable recording head cartridge having an integral
recording head and ink container, is widely used.
Referring ~first to Figure 1, there is shown an
example of an ink jet recording apparatus having such a
replaceable recording head cartridge. In this Figure,
,
a carriage 1 carries four recordlng head cartridges 2A,
2B, 2C and 2D . The carriage 1 sIides on a scanning
rail 3 toward-right and left in the drawing.
The carriage 1 ~is scanningly driven from a
driving motor 4 through~a~drlving pulley 5 and a
driving belt 6. While the carriage 1 is being moved,
the ink is ejected from the recordinq head cartridges
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2A - 2D in accordance with image signals, so that an
image is recorded on the recording material 7.
In the Pigure, the broken lines A i-ndicates
the carriage rest position during the non-recording
period. The carriage rest position is in a non-record
area outside the conveyance path region of the
recording material 7. When the recording operation is
not carried out, or when the recording head is to be
,;
subjected to a recovery operation for recovering the
ejection, the carriage 1 is moved to the rest position
where the recording head is faced to capping means 8,
and the recovery operatioD or the like is performed
there. ~ ~
When the carrlage 1 is~at the rest position A,
the recordin~ heads of~the head cartridges 2a - 2D are
covered with capping means 8, so that the evaporation
of the ink is prevented.
In addition, when the head cartridge is to ~e
replaced, the repIacing operatlon is per~ormed when the
cartridge is at the rest position, by which the ink
scattering is prevented when the head cartridge is
mounted or demounted.~
Thus, the carrlage 1 stops at the rest
position indicated by the broken line ~ whenever the
recording operation is at rest , when the apparatus~is
under normal conditions. However, in the emergency
situation such as jam (paper jam) occtlrrences or
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unexpected shut-off of the power supply, the carriage 1
may stop at a position other than the rest position.
When the head cartridges 2A - 2D are to be
replaced under the emergent situation, the recording
head may be abutted to the recording material 7 because
the clearance between the recording head of the head
cartridge and the recording material 7 is as small as
- approxiMately 0.5 - 2 mm. If this occurs, the
recording head may be damaged.
By the vibration during the mounting or
dismounting operation, the ink scatters from the
recording head with the result of cont~-nAting the
insidP of the recording apparatus.
If the ink scatters to the recording material
conveying path, thP backside of the next recording
material 7 is cont~1n~ted,
If the carriage,1 is left at a position other
than the rest position, the recording heads 2A - 2D are
not capped, so that the ink may evaporate with the
result of improper recording operation.
Upon the jam occurrence or upon the recording
head replacement, a door of the apparatus is opened.
If the operator in advertently touches the carriage in
the jam clearance operation, the carriage may be
unexpectedly moved with the result of interference
between the carriage and a sheet conveying mechanism
when the conveying mechanism is opened. If this
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occurs, the apparatus will be damaged.
In the ink jet recording system, the head is
capped to prevent the ink from drying when the
recording head is at the rest or home position.
However, if the carriage is in advertently moved in the
jam clearance operation or the like, the capping is not
done. If the apparatus is left as it is, the ink is
dried with the result of improper recording.
If the recording head is replaced when the
carriage is not at the rest position, and if the
apparatus is left as it is, the recording head will be
left without capping. If this occurs, the ink is dried
with the result of improper recording.
SUMMARY OF THE INVENTION
Accordingly, it is a principal object of the
present invention to provide an ink jet recording
apparatus wherein the recording head is protected from
damage due to contact thereof with the recording
material, from the protection of the ink due to the
vibration, during the mounting or dismounting of the
recording head.
It is another object of the present invention
to provide an ink jet recording apparatus wherein the
ink is prevented from drying during the non-recording
operation.
It is a further object of the present
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invention to provide an ink jet recording apparatus
wherein the ejection side surface of an ink jet
recording head is prevented from contact with a
carriage guiding surface of the carriage, so that the
ejection side surface and the ejection outlets of the
ink jet recording head can be protected.
It is a further object of the present
invention to provide an ink jet recording apparatus
wherein the recording means is kept capped when a cover
(door) of the apparatus is opened for the purpose of
the jam clearance or head replacing operation, and
wherein the damage of the head by the contact between
the recording means and conveying means when the
conveying means is opened for the jam clearance
operation.
According to an aspect of the present
invention, there is provided an ink jet recording
apparatus wherein recording i9 effected by ejecting ink
to a recording material from a recording head cartridge
detachably mountable to a main assembly of said
apparatus, comprising: a carriage, movable in a main
scan direction, for mounting thereon the recording head
cartridge; mounting and demounting mechanism for
controlling mounting and demounting of the recording
head cartridge on said carriage; and a controlling
member for controlling operation of said mounting and
demounting mechanism to permit mountin~ or demounting
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of the recording head cartridge only when said carriage
is disposed outside a position where it is faced to the
recording material.
According to another aspect of the present
invention, there is provided an ink jet recording
apparatus, comprising: an ink jet head for ejecting ink
through an ejection outlet to effect recording of an
image; a carriage for detachably mounting thereon said
ink jet head, said carriage being movable over a
recording region and a non-recording region; a carriage
guiding surface provided in said carriage to guide said
ink jet head when said ink jet head is mounted on said
carriage; mounting and demounting mechanism for
mounting said ink jet head on said carriage and for
demounting it from said carriage; and a guide for
inclining an ejection side surface of said ink jet head
relative to said carrlage guiding surface when the
mounting and demounting mechanism permits the
demounting of said ink jet head.
According to a further object of the present
invention, there is provided a recording head for
effect recording by ejecting ink, comprising: a
carriage, movable over a recording region and a non-
recording region, for detachably mounting thereon said
recording head; a capping member for capping the
ejection side surface of said recording head when said
carriage is in the non-recording region; a casing
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having a door for permitting mounting and demounting of
said recording head and for casing said carriage member
and said capping member; and control means for
permitting opening or closing of said door only when a
main switch of said apparatus is on-state.
According to a further object of the present
invention, there is provided a recording apparatus
having a cover openable and closable relative to a main
assembly of said apparatus, comprising: conveying means
for conveying a recording material; recording means for
effecting record on the recording material during
relative movement therebetween, movement preventing
means for preventing movement of said recording means
; in interrelation with opening or closing of said cover;
15~ wherein when the cover is opened, said movement
preventing mea~ns prevents movement of said recording
means; and when said cover is closed, the prevention by
said preventlng means is released.
~ These and other objects, features and
advantages of the present invention will become more
apparent upon a consideration of the following
description of the preferred embodiments of the present
: : :
invention taken in con~unction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a top plan view of an exemplary
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ink jet recording apparatus.
Figure 2 is a perspective view of a major part
of an exemplary ink jet reeording apparatus, according
to an embodiment of the present invention.
Figure 3 is a side view of the recording
apparatus illustrating loading of the recordlng head.
Figure 4 is a slde view of the recording
apparatus illustrating the dismounting action of the
recording head.
Figure 5 is a side view of the recording
apparatus illustrating the locked state of the
recording head mounting mechanism.
Figure 6 is a side view of the recording
apparatus illustrating the released state of the
recording head mounting mechanism and the locked state
of a carriage movement preventlng means.
Figure 7 is a side view of a locking member of
a recording head mounting mechanism of another example.
Figure 8 is a side view of a carriage movement
preventing means of another example.
Figure 9 is a side view of another example of
a recording head mounting mechanism.
Figure 10 is a side view of a further example
of a recording head mounting mechanism.
Figure 11 is a sectional view of a part of the
structure shown in Figure 10.
Figure 12 is a side view of an example of an
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ink supply mechanism for the recording head using the
recording head mounting mechanism.
Figure 13 is a perspective view of an example
of a recording apparatus using the present invention.
Figure 14 is a sectional view of an example of
a door locking mechanism.
Figure 15 shows an example of a control
circuit according to an embodiment of the present
invention.
Figures 16 and 17 are flow charts showing an
example of control operation.
Figure 18 is a sectional view of another
example of a door locking mechanism.
Figures 19 and 20 are flow charts illustrating
another examplP of control.
Figure 21 lS a perspective view of a further
example of a carriage locking mechanism.
Figure 22 is a sectional view of a recording
apparatus using the mechanism shown in Figure 21.
Figure 23 is a perspective view of another
example of the releaso preventing means for sheet
conveying means.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the accompanying drawings, the
embodiments of the present invention will be described,
wherein like reference numerals are assigned to the
2 ~ 3 l~
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elements having the corresponding functions.
Referring to Figure ~, there is shown an ink
jet recording apparatus according to an embodiment of
the present invention in a perspective view. Recording
head 2A, 2B, 2C and 2D of a repIaceable cartridge type,
are detachably mounted on a carriage 1. The carriage 1
is movable along a scanning rail 3, and is mounted on a
sliding rail 11 adjacent the other end. The carriage
is reciprocated by a driving motor through a driving
pulley and a driving belt in direction indicated by the
arrow S relative to a recording material 7.
While the carriage 1 is moved, the ink is
ejected through the ink ejection part of the recording
head 2A - 2D in accordance with image signal, by which
an image such as character, figure or the like are
recorded on the recording material 7.
The;recording heads 2A - 2D are of a cartridge
~ type having an integral ink container, and the ink is
- supplied to the ink ejection parts from the integral
ink container.
The recording heads 2A - 2D effect the image
recording with different ink materials. In the cass of
color recordlng, the recording heads 2A - 2D provide
yellow, magenta, cyan and~ black ink materials, for
example. Each of the recording heads 2A - 2D, more
particularly, the ink ejection parts thersof, is in the
form of an ink jet head using thermal energy to eject
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the ink, and therefore, is provided with electrothermal
transducer. Each of the recording head 2A - 2D
produces film boiling by thermal energy applied by the
electrothermal transducers to cause expansion and
contraction of the bubble to eject the ink through the
ejection outlet, by which the image is recorded.
In the following description, when the
reference is made to any of the elements having the
similar structure, or when the reference is made to all
of such elements, the suffixes A - D will be omitted so
that "recording head 2" or the like will be used.
The recording material 7 is seguentially fed
in accordance with the image to be recorded by feeding
rollers 12 and 13, and 14 and 15. The recording
material 7 is guided by a~guiding plate at a lateral
edge, so that the lateral position thereof is confined.
To each of the recording heads 2, the record
image signals are transmitted from signal lines
(flexible c~bIe) 17 through connectors 18A, 18B, 18C
and 18D. The connectors 18A ~ 18D are supported by a
connector holder 19 engaged for movement in a direction
M relative to the carriage 1. The ~1exible cable 17 is
fixed by a confining plate 21 fixed on the connector
holder 19 by screws 20A and 20B. On the carriage 1, a
releasing lever 22 lS movably supported. The releasing
lever 22 is normally effective to maintain the
recording head 2 in the positioned state. At a
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particular carriage position which will be described
hereinafter, it is rotated to release the recording
head 2.
On the carriage 1, there is provided a link
plate 23 engaged with the releasing lever 22 and the
connector holder 19. On the carriage 1, there is
further provided a locking pawl 24 and a locking spring
25 constitutlng the locking means. The locking means,
as will be described hereinafter, normally locks the
releasing lever 22 at the recording head positioning
state. It limits the operation of the releasing lever
22 so as to perm1t rotation thereof to the releasing
position, when the carrlage 1 is abutted to a guide 27
of a casing 26 of the apparatus, that is, when the
carriage 1 is at the carriage rest position (or capping
positlon~ A.
- When the carriage 1 is at the rest position A,
~:~ the ink ejecting parts;of~the recording heads 2 are
capped by the capplng~means 8. The capplng means 8 are
each provided with capping portion 28A, 28B, 28C or 28D
:: ::
: ~ capable of hermetically closing the ink ejecting parts
of the recording heads 2.
; The apparatus~casIng 26 lS provided with a
carriage locking portion 29 which is disposed between
the releasing lever 22 and the carriage 1 when it is at
::: : :
the rest position A. The carriage locking:position 29,
as will be described hereinafter, is sandwiched between
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a side surface of the carriage 1 and an engaging
portion 31 of the releasing lever 22 to -stop movement
of the carriage when the releasing lever 22 is rotated
to the recording head releasing position under the
condition that the carriage 1 is at the rest position
A. Therefore, it constitutes a carri~ge movement
preventing means.
Figure 3 is a side sectional view of a
carriage 1 and a recordin~ part in Figure 2.
In Figure 3, the recording head 2 is mounted
at the correct position by the abutment between
abutment surfaces 36, 37 and 38 of the recording head 2
and abutment surfaces 39, 40 and 41 of the carriage 1.
More particularly, by pushing pin 43 mounted
in the connector holder 19 and urges in the projecting
direction by a spring 42, the recording head 2 is urged
in the leftward detection in Figure 3, by which the
abutting surfaces 36 and 37 are urged to the abutment
surfaces 39 and 40~ ThereEore, the head cartridge 2 is
positioned in the horizontal direction relative to the
carriage. By a downward component f1 of force f urging
the slanted surfaces 44 of the recording head 2 by an
end of the urging pin 43, the abutment surface 38 of
the recording head 2 is urged to the abutment surface
41 of the carriage 1, so that the recording head 2 is
positioned in the height direction.
The connector holder 19 is mounted to the
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connector 18.
The perpendicular surface 45 of the carriage 1
and the perpendicular surface 46 of the recording head
2 function as rough guides when the recording head is
S mounted on the carriage. The ink ejecting part
(ejection part) 130 of the recording head 2 is in
contact with~the capping portion 28 of the capping
means 8 to cover the ink ejector (or ink ejecting
surface 131 shown in Figure 2), when the carriage 1 is
at a predetermined position.
Figure 4 is a~side sectional view when the
recording head 2 is dismounted from the carriage 1. In
Figure 4, when the recording head 2 is dismounted, the
connector holder 19 is first moved toward the right by
a mechanism wh1ch will;be described hereinafter in
conjunction with Figure 5. When the connector holder
19 is moved, the movement of the recording head 2 is
prevented by~the abutments of the rough guides 45 and
46, and thereeore, the connector 18 is separated from
the head connector 47, and simultaneously, the pushing
pin 43 is away from the recording head 2. Therefore,
the recording head 2 is released from the positioned
state. ~
When the connect1on between the head connector
47 and the connector 18 is released, and the pushing
pin 43 is separated from the recording head 2, tha
recording head ~is now detachable in the direction R.
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Figure 5 is a side view illustrating a
mechanism for moving the connector holder 19, and
simultaneously it illustrates a mechanism for locking
the releasing lever Z2.
In Figure 5, a shaft 51 of the connector
holder 19 is integrally coupled with a linX plate 23.
The shaft 51 is engaged with a sliding hole 52 formed
in the carria~ge 1, and the link plate 23 is provided
with a sliding hole 53 which is engaged with a carriage
shaft 54 of a carriage 1. Therefore, the connector
holder 19 and the link plate 23 are slidable toward
front and rear relative to the carriage 1.
The relea~sing lever 22 is rotatable about the
carriage shaft :54, and a projection 55 of the link
~ ~ 15 plate 23 is engaged with a cam slot 56 formed in the
~ ~ releasing lever 22. Therefore, together with the
rotation of the releaslng lever 22, the link plate 23
moves toward right~and left relative to the carriage 1.
The locking pawl 24 is rotatable about a Iocking sha~t
:: 20 57 of the carriage 1, and is urged in the clockwise
direction in Figure 5 by a locking spring 25 stretched
between itself and the carriage 1. Therefore,:as shown
in Figure 5, in the normal recording operation, the
engagement between the locking portion 59 formed in the
locking pawl 24~and the locking portion 60 formed in
the releasing lever 22 prevents the rotation:of the
releasing lever 22.
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Figure 6 is a side view of the releasing lever
22 in the releasing state. When the carriage 1 moves
to the carriage rest position A (Figure 1), the guiding
surface 61 of the locklng pawl 24 on the oarriage abuts
the guiding portion 27 (Figure 1) of the casing 26, and
the locking pawl 24 is rotated along the slanted
surface in the counterclockwise direction in Figure 6
~ against the locklng spring 25.
: When the locking pawl 24 is rotated in this
manner, as shown in Figure 6, the locking portion S9 of
the locking pawl 24 is released from the locking
portion 60 of the releasing lever 22, so that the
engagement therebetween is released, thus permitting
rotation of the releasing lever 22.
In Figure~6j the releasing lever 22 is shown
by solid lines when lt is rotated to a releasing
position permitting dismounting of the recording head
~: 2, and the releasing lever 22 is shown by broken lines
when it is in the position for locking (positioning)
the recording head 2.
When the releasing lever 22 is rotated from
the locking position to the releasing position, the
camming action of the projection 55 and the cam hole 56
: urges the connector holder 19 integral with the link
plate 23 away from the head connector 47 of the
recording head 2 (to the right in Figure 5).;
When the connector holder 19 moves toward the
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rear (to the right in Figure 6), the connector 18 is
moved away from the head connector 47, and the pushing
- pin 43 (Figure 3) is away from the recording head 2, so
that the recording head 2 is brought into the released
S state.
Therefore, the releasing operation of the
~;; releasing lever for the cartridge is made possible only
when the recording head is at the non-recording
(capping) position, and therefore, the recording head
is prevented from being replaced at the recording
position even when the jam occurs. Accordingly, the
inadvertent contact between the recording material and
- the recording head is~prevented, and therefore, the
damage of the recording head resulting from the contact
can be avoided.~ In addition, the ink is prevented from
~; scattering in the apparatus.
The lock releasing mechanism has been
described as of a mechanical type u~sing the sc~nn1ng
:
motion of the carriage, but it may be replaced with
electrically contro1lable means. An example thereof is
shown in Figure 7.
In Figure 7, an arm portion 66 of the locking
:: :
pawl 24 i5 connected with a solenoid shaft 68 of a
solenoid mounted on the carriage 1. The ON-OFF of the
solenoid 67,~that is, the lock releasing motion of the
releasing lever 22 is controlled by an electric control
circuit 69. The carrlage 1~ is pFovided with a position
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detector 70, so that a photosensor 71 disposed at the
apparatus casing side detects whether the carriage is
at the predetermined position.
The signal from the photosensor 71 is supplied
to the electric circuit 69. When the cartridge
mounting carriage is at the capping position, the
solenoid 67 is actuated by the control of the electric
control circuit, and the locking pawl 24 is rotated
in the clockwise direction in Figure 7. Similarly to
the foregoing embodiment, the locking of the releasing
lever 22 is released.
If the releasing lever 22 is simply rotated to
the releasing position, the carri~ge 1 is still Dovable
to the recording region. Therefore, although the
dismounting of the recording head is possible only at
the capping position, the mounting of the recording
head is possible when the carriage is in the recording
region. Therefore, the safety in the mounting of the
recording head (damage of the head or the scattering of
the ink in the apparatus) is not perfectly complete.
From this standpoint, the apparatus of this embodiment
is provided with a carriage lock 29 (Figures 2 and 6)
engageable with the engaging portion 31 of the
releasing lever 22 at the capping position when the
lever is in the released state. This prevents the
carriage 1 from moving from the capping position in the
scanning direction.
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In the shown example, when the carriage 1 is
at the rest position A, the locking portion 29 of the
carriage enters the clearance between a side surface of
the carriage 1 and the engaging portion 31 of the
releasing lever 22. Accordingly, by rotating the
releasing lever 22 to the released position, the
carriage locklng position 29 is interposed between the
carriage 1 and the engaging portion 31, so that the
movement of the carriage 1 in the scanning direction is
prevented.
In this manner, the recording head 2 can be
mounted or dismounted only when the carriage 1 is at
the rest position A. By the dismounting of the
recording head 2, the carriage movement preventing for
movement of the carriage 1 in the scanning direction is
actuated.
According to the embodiment described in the
foregoing relating to an ink jet recording apparatus
using a detachable recording head 2, when ths carriage
1 is at a position other than a rest position A
typically the capping position, the mountlng and
dismounting mechanism of the recording head 2 on the
carriage is locked. Only when the carriage 1 is at the
rest position, the mechanism of the re~ording head 2 is
releasable. In interrelation with the mountlng or
dismounting operation of the recording head 2, the
carriage mo-~ement preventing means is actuated to
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prevent movement of the carriage. Therefore, the
~amage of the recording head attributable to the
inadvertent contact thereof with the recording material
7 or the like, can be prevented. In addition, the
scattering of the ink attributable to vibration in the
mounting or dismounting operation of the recording head
2, can be prevented. Furthermore, the capping of the
recording head 2 at the predetermined position is
assured, so that the evaporation of the ink can be
prevented.
An electrically controllable image may replace
the mechanical means (carriage lock 29 and engaging
portion 31) to prevent movement of the carriage in the
sc~nn-ng direction from the rest position (capping
position).
In Figure 8, the carriage 1 is provided with a
position detector 71, to detect by a photosensor 72
whether the carriage is at the predetermined position
or not. The releasing lever 22 is provided with a
releasing lever sensor 73 to detect motion of the
releasing lever (locking position and releasing
position). When the predetermined position (the rest
position A in Figure 1) of the carriage 1 is detected,
and the dismounting operation using the releasing lever
22 is performed (the rotating motion to the releasing
position, for example), the solenoid 75 is energized by
the control of the electric circuit 74, so that the
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solenoid shaft ~movable shaft) 76 enters the engaging
hole 77 of the carriage 1.
The engaging hole 77 of the carriage 1 is
formed at a position faced to the solenoid shaft, when
the carriage is at the predetermined rest position.
Therefore, the carriage is prevented from
movement and retained at the rest position, by entering
the solenoid shaft 76 into the engaging hole 77 by
energization of the solenoid 75 when the carriage 1 is
at tho predetermined position.
Therefore, also by the structure shown in
Figure 8, the ink jet recording apparatus is such that
the mounting and dismounting mechanism of the recording
head 2 is releasable only when the carriage is at the
predetermined rest posltion, and~that in interrelation
with the mounting and~dismounting of the recording head
2 at this position, the carriage movement preven~ing
means 76 and 77 are actuated to prevent movement of the
carriage.
Accordingly, also in the embodiment of Figure
8, similarly to the foregoing embodiment, the damage of
the recording head 2 due to the inadvertent contact
,
thereof to the recording material 7 or the like, can be
prevented. In addition, the scattering of the ink due
to the vibration upon the mounting or dismounting
operation of the recording head 2 can be prevented.
Furthermore, the capping of the recording head 2 at the
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predetermined position is assured, and therefore, the
~vaporation of the ink can ba prevented.
As described in the foregoing, the damage of
the recording head or the scattering of the ink can be
prevented by limiting the mounting and dismouning of
the recording head at the rest position A (capping
position or non~recording position) by means of the
locking mechanism for the releasing lever or by
preventing the carriage sc~nn-ng movement in relation
with the rotation of the releasing lever to prevent
movement of the carriage during the recording head
replacing operation. However, the damage of the ink
ejecting side of the recording head is more effectively
prevented from being damaged.
In F1gure 9, the releasing lever of the
mounting and dismounting mechanism, is stopped at a
position shown in this Figure, when it is in the
released state,~so that an inside edge 22d of a
gripping portion 2?c constitutes a guide for guiding a
head guiding surface 21 of the ink jet recording head
2. The inside edge 22d is stopped at a position of
height H1 from the carriage guiding surface 1g in the
.
direction perpendicular to the carriage guidlng surface
lg. The height H1 is~larger than a height H2 from an
ink ejection side surface 2B of the recording head 2A
of the head 2 to the ink jet head guiding surface 21.
The rotational radius of the inside edge 22d of the
gripping portion 22- of the releasing lever 22 is
selected as short as possible so as not to lnterfere
the ink container 2B during its rotation, by which when
the releasing lever 22 stops at the releasing position,
the insidP edge 22d is stopped at a position as close
as possible to an inserting portion 1a.
When the mounting and dismounting mechanism is
released, and a projection 2C on which th~ recording
head portion 2A of the recording head 2 is mounted is
inserted into the inserting portion 1a of the carriage
1 or when it is ta~en out therefrom, the inside edge
22d and the ink jet head guiding surface 21 are abutted
to each other (because of the height relations between
H1 and H2), and the bottom surface of the projection 1a
is inclined relative to the carriage guiding surface 1g
within the range in which the carriage guiding surface
1g and a right end of the bottom surface of the
projection 1a are contacted. Therefore, the ejection
side surface 2B o~ the recording head portion 2a is
prevented from being brought into complete surface
contact with the carriage guiding surface 1g. In this
manner, the sliding between the ejection side surface
2B and the carriage guiding surface 1g can be
prevented, so:that the ejection outlets formed in the
ejectlon side surface 2B can be prevented.
In addition, tha grip 22c of the releasing
lever 22 for actuating the mounting and dismountlng
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mechanism is used as a guide for guiding the guiding
surface 21 of the ink jet head, and therefore, the
ejection outlet formed in the ejection side surface 2b
can be protected without increase of the manufacturing
cost.
The description will be made has to a further
embodiment.
As shown in Figures 10 and 11, the mounting
and dismounting~ mechanism 131 of this embodiment is
provided with a guide arm 134 which has a channel like
shape. The ends thereof are supported on a rotational
shaft 1241 projected from a side surface 124h of the
carriage 124 and another rotational shaft (not shown)
projected from an unshown side surface opposite from
the side surface 124h, for rotation in the direction J
and the opposite direction, respectively. At an ~end of
the guide arm 134, an arm gear 134a is formed and is
meshed with a lever gear 132b formed on the releasing
lever 132.
When the releasing lever 132 is at the shown
fixed position, the arm guiding portion 134b of the
guide arm 134 lS dlsposed below a container portion
122b of the ink jet recording head 122. When the
releasing lever 132 is rotated from the fixed position
.
25 to the releasing position indlcated by the broken lines
in the direction G, the guide arm 134 rotates in the
direction J with the rotation of the releasing lever
.
2~80~
132 because of the meshing engagement between the lever
gear 132b and the arm gear 134a, until the guide arm
134 stops at the position indicated by the broken
lines.
As shown in Figure 11, the guide axm 134 stops
at the position indicate~ when the mounting and
dismounting mechanism 131 takes the releasing position.
The arm guide 134b constitutes a guide for guiding the
ink jet head guide surface 1221 of the ink jet head
122. The arm guide 134b stops at a position which is
at a height of L1 from a carriage guidiny surface 124g
from the carriage guiding surface 124g in the direction
perpendicular to the guiding surface 124g. The height
L1 is larger than a height L2 from an ejection side
surface 121a of the recording head portion 21 of the
ink jet head 122 to the ink jet head guiding surface
1221. In the releasing state, the arm guiding portion
134b rotates to a position as close as possible to the
container portion 122b of the ink jet head 122 mounted
on the carriage 124, and stops there.
When the ink iet head 122 is mounted on or
demounted from the carriage 124 with the mounting and
dismounting mechanis~ 131 in the releasing state, the
arm guide 134b Iguide portion) and the ink jet head
guiding surface 1221 are abutted to each other, and the
ejection side surface 121a of the recording head 121 is
prevented from complete surface contact with the
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2 ~ 3 l~
,
-26-
carriage guiding surface 124g, similarly to the
embodiment of Figure 9, within the range in which the
carriage guiding surface 124g is in contact with the
right (in the Figure) end of the bottom surface of the
projection 122a. Therefore, the friction between the
~jectio~ side surface 121a and the carriage guiding
surface 124g can be prevented, so that the ejection
side surfaces~121a and the ejection outlets can be
protected.
A further embodiment will be described. In
the ink jet recording head 2 described in conjunction
with Figure 9, the container 2B for containing the ink
to be supplied to the recording head portion 2A is
integral with~the recording head portion 2A. In the
present embodiment which will be described, the ink jet
recording head does not have such an integral container
portion as shown in Figure 9. Instead, the container
for containing the ink to be supplied to the recording
head portion of the ink jet head is provided in the
main assembly of the ink jet recording apparatus.
Referring to-Figure 12, a connector holder 147
of the carriage 144 is provided with a coupler 155.
The coupler 155 is connected with a tube 155a
communicating with the container (not shown) for
containing the ink to be supplied to the recording head
portion 141 of the ink jet head 142. On the other
hand, the ink jet head 142 is provided with a head
3 ~
coupler 142m at a position corresponding to the main
assembly coupler 155. The head coupler 142m is in
communication with the recording head portion 141
through an ink supply path, not shown.
A projection 142a of the ink jet head 142 is
inserted into a receptor 144a of the carriage 144, and
the releasing lever 152 of the mounting and demounting
mechanism is rotated to the fixed position and is
stopped there, the connector holder 147 moves in the
direction L, upon which the main assembly coupler 155
and the head coupler 142m are couple~ with each other.
The ink contained in the container is supplied to the
recording head portion 141 through the tube 155a, the
main assembly coupler 155, the head coupler 142m and
the lnk supply passage in the order named.
In plaoe of the mounting and demounting
mechanism of this embodlment, the mechanism having the
guide arm described in conjunction with Figures-10 and
11 may be used for the~carriage 144.
Since the~embodiment has the structure
described above, the following advantageous effects are
provided.
When the mounting and demounting mechanism is
released to permit mounting of the ink jet head on the
carriage, the guiding portion for guiding the ink jet
head guiding surface of the ink jet head is provlded at
a such a position as to incline the ejection side
2 ~ , 3 ~
, .
surface of the ink jet head relative to the carriage
guiding surface. This is effective to prevent the
ejection side surface is in complete surface contact
with the carriage guiding surface in the range wherein
the guiding portion guides the ink jet head guiding
surface, and therefore, to prevent the sliding contact
between the ejection side surface and the carriage
guiding surface. As a result, the ejection side
surface and the ejection outlets can be protected with
the simple structure. Therefore, the liability that
the ejection outlets are clogged with the foreign
matter on the carriage guiding sur~ace, can be avoided,
and in addition, the liability that the water repelling
coating layer on the ejection side surface is scraped,
can be avoided.
Additionally, a grip of the releasing lever
for operating the mounting and demounting mechanism is
utilized as a guide for guiding the ink jet head
guiding surface, and therefore, the increase of the
20 ~manufacturing cost is not caused.
In Figure 13, an openable door (front door)
220 is provided at a front part of the ink jet
recording apparatus.
The door 220 is provided with a projection
2S 241, and the main assembly of the recording apparatus
has a cut-away portion (opening) 242 opened and closed
by the projection 241. The cut-away portion 242 is
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--29--
effective to make the replacement of the recording head
portion 1A - 1D (recording head 1) at the capping
position.
At the backside of the door 220, a locking
5 member 221 cc~nstituting a locking means for cooperating
with the locking mechanism of the main assembly of the
apparatus to limit the opening and closing of the door,
is projected.
The locking means functions to prevent the
10 door 220 from changing from an open state or closed
state (current state) to another state. The locking
means, as will be described hereinafter, is effective
to prevent the operator from freely opening and closing
the door 220 when the door 220 is closed. When for
15 example, the main switch is actuated, the door 220 is
freely openable or closable, but when the main switch
is not actuated, the door 220 is not openable or
closable.
Figures 14A, 14B and 14C are sectional plan
20 view taken along a line II-II of Figure 13 to
illustrate structure and operation of the locking
means. Figures 14A, 14B and 14C illustrate the actions
when the door 220 is moved from the open state to the
closed state, when the main switch of the main assembly
25 of the apparatus is rendered on. When the main switch
is on, the solenoid 223 attracts the movable iron
memb~r 224 by the signal from a controller, so that it
2 ~ 3 1~
-30-
is in the locking state.
With the closing motion of the door 220, the
locking member 221 moves in the direction indicated by
an arrow along the locking means. As shown in Figures
14A and 14B, the locking member 221 depresses a
projection 225 urged by the spring 226 while moving
therealong, until it reaches the closing position of
Figure 14C. At this closing position, the projection
225 is engaged into the recess of the locking member
221 by the spring 226, so that the door 220 is
completely closed. In addition, with this state, the
locking member 221 depresses the door sensor 222, upon
which a controller of the apparatus main assembly
detects the closer of the door 220. Since the main
switch is actuated, the solenoid 223 continues to keep
the memb~r 224 attracted, even in the state of Figure
14, so that the door 220 is freely mov~ble. Thus, as
; long as the main switch is in on-state, the door 220
can be freely~opened or closed.
After the door 220 is completely clossd, and
the main switch is rendered of~, the solenoid 223 is
deenergized to release the movable iron member 224.
This is shown;in Pigure 14D. The released member 224
projects outward by the urging force of the spring, by
which a pawl portion of the movable member enters the
engaging hole 231 of the locking member 221, an~
therefore, the locklng member 221 is locked so as to
-31-
prevent opening and closing of the door.
When the main switch is rendered off when the
door 220 is opened with the main switch actuated, the
movable member 224 projects to prevent movement of the
locking member 221, as shown in Figure 14E, and
therefore, the door 220 is prevented from closing.
Thus, in this embodiment, the door 220 is openable or
closable only when the main switch is in the on-state.
Figure 15 is a block diagram of tha entlre
system of the recording apparatus of this embodiment.
The system comprises a controller 300 for controlling
the entirety~of the recording apparatus. The
controller 300 comprises a CPU 301 in the form of a
microprocessor or the like, a ROM 302 storing various
data and CPU control program which will be described in
conjunction with Figures 16, 17, 18 and 19, and a RAM
303 usable as a work area for the CPU 301 and used for
a temporary storing of various data.
The CPU 301 receives a record starting signal
from a record starting key 304, a door closure
detection signal~from the door sensor 222, a sheet
discharge signal from the sheet discharge sensor 216,
or the like.
On the other hand, the CPU 301 is responsive
; 25 to the lnput signals to control various portions and is
also effective to perform the image recording operation
in accordance with lmage signals from the cost
2 ~ 3 ~
apparatus or the like.
The CPU 301 produces solenoid control signals
in response to the detection signals or the like to
control the solenoid driving source 305, so that the
operation of the solenoid 223 is controlled.
When the CPU 301 discriminates paper jam or
the basis of detection signals from the discharge
sensor 216 or~the like, it turns the sheet jam lamp 306
(display) on.
In the recording operation, the CPU 301
controls the motor driver 307 to control the motor such
as carriage moving motor 308, and also controls
operation of the recording heads 201A - 201D by
controlling the recording head driver 308 in accordance
with the image signals from the host apparatus or the
like.
Figures 16 and 17 are flo-~ charts illustrating
the main routine and interruption routine of the
control operation of the ink jet recording apparatus
described in the foregoing.
In Figure 16, when the main switch of the
recording apparatus is actuated, the initial setting is
performed for the CPU and the R~ or the like of the
controller (not shown) at step S1. After the initial
setting is completed, the locking for the door 220 is
released to permit interruption at step S2. A
particularly, the solenoid 223 is energized to attract
.
the movable iron piece 224 to retract ths pawl portion
of the movable plece 224 from the engaging hole 231 of
the locklng member 221, thus releasing it. Then, the
operator is permitted to open the door 220.
At step S3, the opening of the door 220 is
detected by the door sensor 222. If the door 220 is
opened, the recording operation is not started, and the
checXing operation is continued in the closed loop
until the door is closed.
When the door 220 lS closed, the recordlng
head 201 is capped with the capping means 212 at step
S4. Afker the capping, the depression of the starting
key by the operator is awaited at step S5.
When the record start key is depressed, the
recording operation is started at step S6. After the
completion of the recording operations for a
predetermined number of sheets, the recording head 201
is capped at step S7. After the capping, the operation
returns to step S5 so as to prepare for the next
recording operation, that is, the next depression of
the start key is awaited.
Referring to Figure 17, the description will
be made as to the interruption routine. When the door
220 is opened, and the~door sensor 222 detects the
event, an interruption request is made to the CPU of
the controller. If the operation of the main routine
of Figure 16 is subsequent to the step S3 r the
:
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-34-
interruption is already permitted, and therefore, the
operation shifts to the interruption routine shown in
Figure 17.
In Figure 17, at step S8, the recording
; 5 operation is stopped on the premise that the door 220
is opened during the recording operation. More
particularly, the driving pulse and the ink ejection
pulse to the recording head 201 is stopped. In
.
addition, the driving pulse to the stepping motor 308
is stopped to stop the motion of the carriage 202. The
record stopping operation does not adversely af~ect the
apparatus even if it is carried out not during the
recording operation. At step S9, the step number of
the main routine is changed to 11311 before returning to
the main routine. By the change of the step number,
the main routine operation starts at the step S3
immediately after the~operation returns to the-main
routine from the interruption routine.
Becauss of the above-described interruption
processing, the capping operation is always effected
~: :
after the door 220 lS opened or closed.
If the door 220 is opened or clos~d, the
recording material is detected by the sheet discharge
sensor 216 ln Figure 15. The sheet jam~is
discriminated because the sheet exists at the sheet
discharge sensor 216 before the record start key is
depressed. Therefore, the sheet jam lamp 219 ln Figure
:
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'
: , : : .
2 ~ 3 ~
-35-
13 is lid on to promote the operator to remove the
recording material and to reactuate the main switch
According to the embodiment described in the
foregoing, the situation in which the recording head
201 is left without being capped, occurs only when the
main switch is deactuated during the recording or when
the door 22Q is opened during the re~ording.
Therefore~ the recording head 201 is not left without
being capped except for the case in which the operator
deliberately does it.
Therefore, according to this embodiment-, the
liability of the recording head 201 left without being
capped, can be avoided almost completely. Therefore,
the soIidification of the ink due to operator's
inadvertent error can be avoided.
; Figure 18 shows the door locking mechanism and
illustrates its operation,~ according to another
embodiment. Figure 18 is a sectional plan view of the
same portion as in Pigure 14.
Figure 18A shows the state in which the
locking member 221 is disposed at the open side when
the main switch is not actuated~ Figure 18B shows the
state in which the locking member 221 is at the closing
position when the main switch is not actuated. Figure
25 18C shows the state in which the locking member 221 is
in the middle between ~the open and close states when
the main switch in the on-state
3 l~
-36-
In these Figures, an engaging member 227 made
of iron is rotatably mounted about a pivot 229 on the
main assembly of~the recording apparatus. The engaging
member 227 is urged by a spring so as to project beyond
the surface on which the locking member 221 passes, as
shown in Figure~18A.
The engaging member 227 has a stop surface
227A and a slide surface 227B and is capable of
preventing the alosing movement of the locking membsr
221, but permlts the opening movement thereof, because
of its configuration.~
On the other hand, the locking member 221 has
a configuration corresponding to the projection (pawl)
of the engaging member 227. More particularly, the
configuration~is such as to permit the opening
direction movement but prevents the entering direction
movement. It also comprises a recess 232 engageable
.
with the engaging member 227 at the close position
shown in Figure 18B.
Adjacent the engaglng member 2Z7, a solenoid
230 is disposed. The solenoid 230 is responsive to a
signal from the CPU to attract the engaging member 227
against the spring force of the spring 2Z8 to re~ract
it so as not to interfere the locking mem~er 221.
Similarly to the foregoing embodiment, a door sensor
222 is provided.
When the door 220 is closed~, and the locking
.
. -
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: .:
.: ~ ''. '" . , ' ' ' ~ '
~;' '' ~' . :
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;
. .
3 ~
,
-37-
member 221 is at the position shown in Figure 18B, the
locking member 221 pushes the door sensor 222 as long
as the main switch is in on-state, and therefore, the
CPU discriminates the closure of the door 220.
If on the other hand, as shown in Figure 18B,
when the door 220 is at the closed position, and the
main switch is in the on-state, the solenoid 230 is
deenergized, so that the engaging member 227 is
projected. Therefore, the locking member 232 is at the
-losing position.
However, when the locking member 221 moves in
the opening direction, the locking member 221 is
movable to the right since the engaging member 227 is
retractable against the spring 228. Therefore, the
door 220 is permitted to open. Therefore, the lo-king
member 221 makes the motion from the Figure 18B state
to the Figure~18A state through the Figure 18C state.
Therefore, the door 220 is opened. When the door 220
is opened, the engaging member 220 is projected beyond
the locking member passing surface by the spring 228.
This prevents the locking member 221 from moving ln the
closing direction (to the left). In other words, the
door 220 is prevented from being closed.
When the door 220 is closed~with the main
switch in the on-state, the situation is the same as
when the door 220 is opened with the maln switch non-
actuated, until the door 220 is completely opened.
. '' :
2 ~ 3 ~
-38-
In the cass o~ the main switch actuated, when
the door sensor 222 is opened, the CPU detects the
opening of the door 220, and the energized state of the
solenoid 230, to attract the engaging member 227, is
maintained until the door sensor is depressed by the
closure of the door 220.
Therefore, when the main switch is in the on-
state, and the door 220 is closed, the door 220 is can
be opened and reclos d.
In the above-described manner of the control,
the door 220 can be closed only when the main switch is
in the on-state, in the present invention, too.
Figures 19 and 20 are flow charts of a main
routine and an interrupti(~n routine for the control
operatio~ of the apparatus according to the Figure 18
embodiment.
In Figure 19, when the main switch of the
recording apparatus is actuated, the initial setting
operation is effected for the CPU, the RAM or thQ like
of the controller (not shown) is performed at step S11.
After the initial setting is completed, the
interruption operation is permitted at step S12.
At step S13, the discrimination is made as to
whether or not the door 220 is opened, using the door
sensor 222. If so, the operation pro~eeds to a step
S15 where instructions is sent to the solenoid 230 to
attract the engaging member 227. Until the door 220 is
.. . . .
~$~3~
,~.
-39-
closed, the checking operation is performed in the
loop, at step 513.
On the other hand, if the door 220 is clo~ed,
or if it is closed already at the time of the actuation
of the main switch, the operation proceeds to a step
S14 where the solenoid 230 is deenergized, and the
recording head 201 is capped at step S16. After the
capping, the depression of the record start key by the
operator is awaited in the closed loop, at step S17.
In response to the depression of the record
start key, the reco.-ding operation starts at step S18.
When th~ predetermined number of sheets are processed
for the recording, the recording head 201 is capped at
step S19.
After the completion of the capping, the
operation returns to the step S17 for the preparation
for the next recording operation, that is, the next
depression of the record start key is awaited.
The desoriptlon will be made as to the
interruption routins of Figure 20. When the door 220
is opened, and the door sensor 222 detects the event,
an interruption request is supp;lied to the CPU of the
controller. If the operation in the main routine of
Figure 19 is at a step subsequent to the step S13, the
interruption is already permitted, and therefore, the
control operation proceeds to the interruption routine
of Figure 20.
2 ~ 3 ~
-
-40-
In Figure 20, at step S20, the recording
operation is stopped on the premise that the door 220
is opened during th~ recording operation. More
particularly, the driving pulse for the recording head
1 and the ink ejection pulse is stopped, and the
driving pulse for the stepping motor 208 is stopped,
and the motion of the carriage 202 is stopped. The
recording operation stepping control does not adversely
affect the recording apparatus, even if it is carried
out not during the recording operation. At step S21,
before the operation returns to the main routine, the
step number is changed to "13". By the change of the
step number, the control operation starts at the step
S13 in the main routine, immediately after the
operation returns thereto from the interruption
routine.
Because of the above-described interruption
routine, the capping operation is always effected
whenever the door 220 is opened or closed.
If the door 220 is opened or closed during the
recording operation, the recording material is detected
by the sheet discharge sensor 216, and the sheet jam is
discriminated because th,- recording material exists at
the position of the sheet discharge sensor 216 before
the record start key is depressed. Therefore, the
sheet jam lamp 19 of Figure 14 lS lit on to promote the
operator to remove the recording material and to
~ ,~:' , : -
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,
.
3 l~
-41-
reactuate the main switch.
The similar advantageous effects as in the
previous embodiment are provided. More particularly,
the recording head 201 is left without being capped
only when the main switch is deactuated during the
recording operation or when the door 220 is opened
during the recording operation. Therefore, the
recording head is not left without being capped, except
for the operator deliberately does it.
Accordingly, the liability that the recording
head 1 is left without being capped, can be eliminated
almost completely. Therefore, the solidification of
the ink in the recording head 201 due to the
inadvertent error of the operator, can be prevented.
Additionally, according to this embodiment,
the door 220 is permitted to be opened evan if the main
switch is not actuated. Therefore, as contrasted to
the foregoin~ embodiment, tha recording head 1 can be
replaced more safely. In addition, the number of
structural parts of the locking mechanism for tha door
220 can be reduced, thus decreasing the manufacturing
cost.
In the foregoing embodimelts, four recording
heads 1a - 1d are used in the color ink jet recording
apparatus. However, the present invantion is
applicable to the apparatus having a single recording
head (single ink ejecting portion) for a single color
3 ~
-42-
record, and to an ink jet recording apparatus capable
of tone recording using plural recording head providing
different densities in the same color, or another ink
jet recording apparatus, irrespectiv of the number of
the recording heads.
The replaceable recording heads 201A - 201D
-may be in the for~n of a recording head comprising
separate ink ejector and ink con~.ainer which are
connected through a coupler and tube, for example, the
form of a recording head ~aving ink ejector without thP
ink container, or the form of a cartridge type
recording head having an integral ink ejector and the
ink container.
The present invention is applicable to a
serial recording type ink jet recording apparatus
having a recording head mounted on a carriage movable
along the recording material or to a line type ink jet
recording appara,us using a.line recording head
covering the entirety or a substantial part of the
recording width ~or the recording material. The same
advantageous effects can be provided.
The safety of the recording head when the door
opened is further assured by preventing movement of the :.
recording head fron the non-recording position (capping
position) to the recording region, when the door is
opened.
The description will be made as to the
,
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~8~3~
-43-
movement limiting means for the recording head
interrelated with the opening and closing of the door.
Referring to Figure 21, the movement
preventing means 408 is sho-~n. A channel-like movement
preventing member 408a is mounted for rotation about a
shaft 408b at the home position for the carriage 406a.
The movement preventing member 408 is urged in the
direction c in Figure 21 by a tension spring 408co It
is retained with the bottom end contacted to the
stopper 408d. A tap~r 408a1 is formed at an end of the
movement preventing member 408a. At a predetermined
position on the bottom surface of the carriage 406a,
an engaging hole 408e is formed.
The preventing member 408 is operated in
interrelation with the opening and closing of the
cover. More particularly, as sh~wn in Figure 22, the
recording apparatus has such a structllre that a cover
412 is openable from the main assembly 411 of the
apparatus. The inside surface of the cover 412 is
provided with a projection 408f. The projection 40~f
urges an end 408a2 of the preventing member 408a when
the cover 412 is closed. When the cover 412 is opened,
it releases the urging.
Therefore, as shown by the chain lines of
Figure 22, when the cover 412 is closed, the projection
408f urges the end 408a2, and by the urging, the
preventing member 408 rotates in the direction d about
2 ~ 3 ~
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-44-
the shaft 408b, so that the tapered portion 408al and
the engaging hole 408e are in the released state.
Therefore, the carriage 406a is movable along a slide
rail 406c, so that the recording operation can be '
carried out without obstruction.
When, on the other hand, the cover 412 is
opened for the purpose of interchanging of the
recording head 406b or the like, the projection 408f
ceases the urging of the end 408a2 of the preventing
member 408a, so that the preventing member 408a rotates
by the tension of the spring 408c until it abuts the
sto~per 408d. If the carriage 406a is at the home
position (the chain line position of Figure 21), the
leading end of the tapered portion 408a1 is engaged
into and locked into an engaging hole 408e formed in
the carriage 406a is indicated b~ solid lines.
Therefore, the carriage 406a is prevented from-movement
along the slide rail 406c, and therefore, the
unexpected movement of the carriage 406a is prevented
at the time of the head exchanging operation.
If the carriage 406a is stopped at the
position other than the home position with the cover
412 opened, due to an unexpected power supply failure
or the like, the bottom of the carriage lowers the
preventing mem~er 408a along the tapered portion 408a1,
when the carriage 406a is moved to the home position,
and in addition, the tapered portion 408a1 enters the
2 ~ 3 ~
-45-
engaging hole 408e by the urging of the spring 408c.
Therefore, the carriage 406a is prevented from movement
from the home position.
Thus, when the cover 412 is opened, the
movement preventing member 408a operates in association
with the opening o~ the cover 412 to limit the movement
of the carriage 406a disposed at the home position.
When the cover 412 is closed, the movement prevention
for the carriage 406a is released. Therefore, the
carriage 406a is not ir.advertently moved upon the
exchange of the recording head 406b or the jam
clearance operation or the like.
Opening means 409 is provided to open and
separate between the conveying roller 404a and the
pinch roller 404b and between the discharging roller
404c and the pinch roller 404d to facilitate the jam
clearance operation when the recording sheet 402 is
jammed.
As shown in Figure 23, hooks 404j1 and 404j2
are fixed on the shafts 409a1 and 409a2. The hooks
404j1 and 404j2 have integral gear portions 409b1 and
409b2 rotatable about the shafts 409a1 and 409a2. One
409b1 of the gear portions is meshed with a rack 409d
through a cam gear 409c, and the other gear portion
409b2 is meshed directly with a rack 409d.
An operating lever 409e is mounted on the
shaft 409a2. Therefore, when the operatin~ lever 409e
.
3 ~
-46-
is rotated in the direction e in Figure 23, the hook
404j2 rotates in the direction e to be disengaged from
a pressing shaft 404e2, and simultaneously, the rack
409d slides in the direction f. Therefore, the hook
404j1 rotates in the direction g, so that it is
disengaged from the pressing shaft 404e1, and the
pressing between the conveying roller 404a and the
pinch roller 404~ and the pressing between the
discharging roller 404c and the pinch roller 404d are
released. An opening preventing member 41Oa is in the
broken line state of Figure 23.
At this time, arms 404f1 and 404f2 are pulled
by the springs 404i1 and 404i2 and are retained at a
position where parts of the arms 404f1 and 404f2 are
contacted with a supporting shaft 404h. Further, when
the operating lever 409e is rotated in the direction e,
the arm 409c1 mounted on the cam gear 409c1 rotates the
cam 409f fixed on the supporting shaft 404h, and raises
che upper guide 404g1 and the pinch roller 404b, as
shown in Figure 23.
By doing so, the sheet conv-ying means 40~ is
opened widely so as to facilitate the jam clearance
operation to remove the recording sheet 402 from the
conveyance passage.
In the state of Figure 23 in which the sheet
conveying means 404 is opened, the upper guide 404g1
and the pinch roller 404b enter the scanning region of
2 ~ 3 ~
--47--
the carriage 406a. This means that if the operating
lever 409e is operated when the carriage 406a is
stopped at the position other than the home position,
the upper guide 404gl and the pinch roller 404b
5 interfere the carriage 406a. In view of this, the
present embodiment is such that only when the carriage
406a is at the home positlon, the opening of the sheet
conveying means 404 is permitted, and when the carriage
406a is at the other position, the opening of the
10 conveying means 404 is prevented. This is done by the
openin~ preventing means 410.
As shown in Figure 23, the opening preventing
means 410 comprlses L-shaped opening preventing member
41Oa rotatably mounted about a shaft 41Ob. When the
15 opening preventing means 41Oa is in the state shown by
the solid line of Figure 23, an end of the rack 409d
abuts the opening preventing membèr 41Oa. To the
opening preventing member 41Oa, an end of a connecting
shaft 41 Oc is rotatably mounted, and to the other end
20 of the connecting~ shaft 410c, the L-shaped locking
member 41Od is mounted. When the carriage 406a moves
to the home position, the locking member 41Od ls
engaged with the bottom end of the carriage 41Oa to
slide the connecting shaft ~410c, in a direction h in
25 Figure 23.
Therefore, when the carriage 406a is at the
position other than the home position, the opening
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preventing member 41Oa is at the position indicated by
the solid line in Figure 22 to limit the sliding of the
rack 409d in a direction f. Therefore, it is not
possible to move the operating lever 409e in the
direction e, so that the opening of the sheet conveying
means 404 is prevented.
When the sheet conveying means 404 is opened
for the jam clearance operation or the like, the
connecting shaft 410c slides in the direction h by the
movement of the carriage 406a to the home position, the
opening preventing member 41Oa rotates to ths position
indicated by th broken lines in Figure 23, and
therefore, the rack 409d becomes slidable state, and
therefore, the sheet conveying means 404 can be opened
by operating the operating lever 409e. At this time,
the carriage 406a is prevented to move by the movement
preventing means 408, as described hereinbefore.
As described in the foregoing, according to
the present invention, the sheet conveying means 404
can be opened when the carriage 406a is at the home
position. When the carriage 406a is at the other
position, the opening is prevented by the opening
preventing means 410, so that the damage of the
carriage 406a or the recording head 406b or the like
can be prevented.
In the foregoing description, the recording
means is in the form of an end jet recording type.
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Preferably, it is of a type wherein an electrothermal
transducer is energized in accordance with record
signals to heat the ink so as to produce fil.n boiling,
which creates a bubble so as to e~ect the ink through
the ejection outlet.
The present invention is particularly suitably
usable in an ink jet recording head and recording
apparatus wherein thermal energy by an electrother~al
transducer, laser beam or the like is used to cause a
change of state of the ink to eject or discharge the
ink. This is because the high density of the picture
elements.and the high resolution of the recording are
possible.
The typical structure and the operational
pxinciple are preferably the-ones disclosed in U.S.
Patent Nos. 4,723,129 and 4,740,796. The principle and
structure are applicable to a so-called on-demand type
recording system and a continuous type record.ing
system. Particularly, however, it is suitable for the
on-demand type because the principle is such that at
least one driving signal is applied to an
electrothermal transducer disposed on a liquid (ink)
retaining sheet or liquid passage, the driving signal
being enough to provide such a quick tem~erature rise
beyond a departure from nucleation boiling point, by
which the thermal energy is provided by the
electrothermal transducer to produce film boiling on
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the heating portion of the recording head, whereby a
bub~le can be formed in the liquid (ink) corresponding
to each of the driving signals. By the production,
development and contraction of the the bubble, the
liquid (ink) is ejected through an ejection outlet to
pro~uce at least one droplet. The driving signal is
preferably in the for~ of a pulse, because the
development and contraction of the bubble can be
effected instantaneously, and therefore, the liquid
(ink) is eiected with quick response. The driving
signal in the form of the pulse is preferably such as
disclosed in U.S. Patents Nos. 4,463,359 and 4,345,262.
In addition, the temperature increasing rate of the
heating surface is preferably such as disclosed in U.S.
Patent No. 4,313,124.
The structure of the recording head may be as
shown in U.S. Patent Nos. 4,558,333 and 4,459,600
wherein the heating portion is disposed at a bent
portion, as well as the structure of the co.~bination of
the ejection outlet, liquid pass~ge and th~
electrothermal transducer as disclosed in the above-
mentioned patents. In addition, the pres nt invention
is applicable to the structure disclosed in Japanese
Laid-Open Patent Application No. 123670i1984 wherein a
common slit is used as the ejection outlet for plural
electrothermal transducers, and to tha structure
disclosed in Japanese Laid-Open Patent Application No.
2 ~ 3 ~
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138461/1984 wherein an opening for absorbing pressure
wave of the thermal energy is formed corresponding to
the ejecting portion. This is because the present
invention is effective to perform the recording
operation with certainty and at high efficiency
irrespective of the type of the recording head.
The present invention is effectively
applicable to ~ so-called full-line type recording head
having a length corresponding to the maximum recording
width. Such a recording head may comprise a single
recording head and plural recording head combined to
cover the maximum width.
In addition, the present invention is
; applicable to a serial type recording head wherein the
recording head is fixed on the main assembly, to a
replaceable chip type recording head which is connected
electrically with the main apparatus and can be
supplied with the ink when it is mounted in the main
asse~bly, or to a cartridge type recording head having
an integral ink container.
The provis1ons of the recovery means andtor
the auxiliary means for the preliminary operat~ion are
preferable, because they can further stabilize the
effects of the present invention. As for such means,
there are capping means for the recording head,
cleaning means therefor, pressing or sucking means,
preliminary heating means which may be the
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electrothermal transducer, an additional heating
element or a combination thereof. Also, means for
effecting prellminary ejection (not for the recording
operation) can stabilize the recording operation.
As regards the variation of the recording head
mountable, it may be a single corresponding to a single
color ink, or ~ay be plural corresponding to the
plurality of ink materials having different recording
color or density. The present invention is effectively
applicable to a3 apparatus having at least one of a
monochromatic mode mainly with black, a multi-color
mode with different color ink materials and/or a full-
color mode using the mixture of the colors, which may
be an integrally formed recordlng unit or a combination
of plural recordlng heads.
Furthermore, in the foregoing embodiment, the
ink has been liquid. ~It may be~, however, an ink
material which is solidified beIow the room temperature
but liquefied at the room temperature. Since the ink
is controlled within the temperature not lower than 30
~C and not higher than 70 ~C to stabilize the viscoslty
of the ink to provide the stabilized ejection in usual
recording apparatus of this type, the ink may be such
that it is liquid within the~temperature range when the
recording signal is the present invention is applicable
to other types of ink. In one of them, the temperature
rise due to the thermal energy is positively prevented
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by consuming it for the state change of the ink from
the solid state to the liquid state. Another ink
material is solidified when it is left, to prevent the
evaporation of the ink. In either of the cases, the
application of the recording signal producing thermal
energy, the ink is liquefied, and the liquefied ink may
be ejected. Another ink material may start to be
solidified at the time when it reaches the recording
material. The present invention is also applicable to
such an ink material as is liquefied by the application
of the thermal energy. Suoh an ink material may be
retained as a liquid or solid material in through holes
or recesses formed in a porous sheet as disclosed in
Japanese Laid-Open Patent Application No. 56847t1979
and Japanese Laid-Open Patent Application No.
71260/1985. The sheet is ~aced to the electrothermal
transducers. The most effective one for the ink
materials described above is the film boiling system~
The ink jet recording apparatus may be used as
an output terminal of an information pro-essing
apparatus such as computer or the like, as a copying
apparatus combined with an ima(~ reader or the like, or
as a facsimile machine havlng lnformation sending and
receiving functions.
In the foregoing descriptionj the recording
means is in the form of an~ink jet recording type, but
the present invention lS applicable to the other type
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such as thermal transfer type recording, heat sensitive
recording; or to an impact type recording system such
as wire dot type recording system.
While the lnvention has been described with
reference to the structures disclosed herein, it is not
confined to the details set forth and this appl~ication
is intended to cover such modifications or changes as
may come within the purposes of the improvements o~ the
scope of the following claims.
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