Note: Descriptions are shown in the official language in which they were submitted.
CA 02481898 2011-05-31
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BLADE HOLDING DEVICE, ASSEMBLY INCLUDING THE SAME, AND
METHOD OF OPERATING ASSOCIATED THERETO
Field of the invention:
The present invention relates to a blade holding device. More particularly,
the present invention relates to a blade holding device such as the ones
employed to cooperate with rollers of machines used in the pulp and paper
industry, and other like industries. The present invention also relates to an
assembly, such as a machine for example, provided with the device and
corresponding rollers, as well as to a method of operating associated thereto.
Background of the invention:
It is known in the art that a paper machine such as the ones used in the
pulp and paper industry, generally comprises an important number of rollers
that
have different utilities. Typically, the rollers must be cleaned by means of
scrapers. Each scraper is generally provided with a blade-holder which
contains
an interchangeable blade, and each blade-holder must generally carry out a
constant pressure or some kind of contact pressure on the roller via the blade
so
as to be able to properly clean the surface of the roller.
These types of blade-holders have been used in the industry of pulp and
paper for many years now. Known in the art are two main types of blade-
holders,
namely: a) flexible blade-holders whose loading system operates by means of a
hose filled with air, glycol, silicon, or the like; and b) rigid blade-holders
which are
not provided with such a direct loading system. The main function of blade-
holders is to retain a blade onto a corresponding roller and enable the blade
to
clean the roller while keeping a contact pressure when the roller turns. In
order to
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carry out the cleaning, the blade must typically be in compression (loaded) on
the
roller, and it is for this reason that the compression or loading system of a
blade-
holder is very important.
Also known in the art are DST and KF blade-holders, and the various
disadvantages associated thereto, namely the fact that they require a hose for
operation thereof, the hose drying up after a certain service time, which
requires
substantial maintenance, and thus in turn prevents production of paper, as
well
as the fact that these blade-holders generally require the assistance of a
control
box for proper operation thereof, and thus complicated electronics and
corresponding maintenance and servicing thereof are required, and the like,
which is also very disadvantageous for obvious reasons.
Also known to the Applicant are the following US patents and/or patent
applications describing different blade holding devices: 3,144,674; 3,377,644;
3,778,861; 3,800,357; 3,866,266; 4,151,797; 4,367,120; 4,444,102; 6,120,649;
6,328,853 B1; 6,389,669 131; 6,547,932 131; 6,749,725 131; and 2004/0149414
Al.
Also known in the art are the disadvantages associated with some of the
blade holding devices described in the above-mentioned documents, namely the
fact that: a) an intricate design and complex cooperation between the
components prevent them from being easily interchangeable and/or serviced,
particularly when the blade needs to be replaced; b) because of their
intricate
design, any debris from the roller which may find itself accumulated onto the
blade holding device and the components thereof may prevent proper operation
of the blade holding device; c) the blade holding devices and corresponding
blades thereof are not intended to follow the roller through a substantial
change in
diameter of the roller, thereby requiring the positioning of the blade holding
device
and/or the frequent replacement of different sized blades; d) the blade
holding
devices generally comprise projecting components which may adversely
cooperate with the rollers, with debris accumulated thereon, and with other
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components of the assemblies in which they are used; e) the blade holding
devices are not intended to have their blades maintain, in a continuous
manner, a
contact pressure on the rollers, and this throughout a wide range of roller
diameters; and f) the blade holding devices are not devised to allow the blade
to
be easily, quickly, and adjustably operated between contact positions and
retracted positions.
Hence, in light of the aforementioned, there is a need for a improved blade
holding device which, by virtue of its design and components, would be able to
overcome some of the aforementioned prior art problems.
Summary of the invention:
An object of the present invention is to provide a device which satisfies
some of the above-mentioned needs and which is thus an improvement over
other related blade holding devices known in the prior art.
In accordance with the present invention, the above object is achieved, as
will be easily understood, with a blade holding device for selectively and
adjustably maintaining a contact pressure onto a neighboring roller, the
device
comprising:
a base;
a hinge having first and second components, the first component being
mounted onto the base, and the second component being pivotably moveable
with respect to the first component about a pivot axis;
a support plate, said support plate being mounted onto the second
component of the hinge, and thus being pivotably moveable with respect to the
base;
a blade being removably mountable onto a front portion of the support
plate, the blade being operable between a contact position where the blade
rests
against the roller for maintaining the contact pressure, and a retracted
position
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where the blade is drawn away from said roller for removing the contact
pressure;
and
biasing means, the biasing means being operatively connected between
the base and the support plate for biasing the support plate and corresponding
blade into the contact position.
According to another aspect of the invention, there is also provided an
assembly comprising:
a roller; and
a blade holding device positioned adjacent to the roller for selectively and
adjustably maintaining a contact pressure onto said roller, the device
comprising:
a base;
a hinge having first and second components, the first component
being mounted onto the base, and the second component being pivotably
moveable with respect to the first component about a pivot axis;
a support plate, said support plate being mounted onto the second
component of the hinge, and thus being pivotably moveable with respect to
the base;
a blade being removably mountable onto a front portion of the
support plate, the blade being operable between a contact position where
the blade rests against the roller for maintaining the contact pressure, and
a retracted position where the blade is drawn away from said roller for
removing the contact pressure; and
biasing means, the biasing means being operatively connected between
the base and the support plate for biasing the support plate and corresponding
blade into the contact position.
Preferably, the blade holding device comprises retracting means for
operating the support plate and corresponding blade into the retracted
position.
The retracting means may take on various suitable embodiments according to the
present invention, as will be explained in greater detail hereinbelow.
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For example, and preferably, the retracting means comprise:
a hinge having first and second components, the first component being
mounted onto the base, and the second component being pivotably moveable
with respect to the first component about a pivot axis; and
5 a lever, said lever being mounted onto the second component of the hinge
of the retracting means, and thus being pivotably moveable with respect to the
base, said lever having a front portion cooperating with a rear portion of the
support plate for displacing the same so as to reactively displace the front
portion
of the support plate and corresponding blade away from the roller, into the
retracted position.
Preferably also, the retracting means comprise a retracting arm, the
retracting arm being pivotably mountable onto the base and being provided with
a
cam, the cam being positioned adjacent to the lever, and being shaped and
sized
so that when the retracting arm is operated into a first configuration, the
cam is
away from said lever, thereby enabling the biasing means to bias the support
plate and corresponding blade into the contact position, and when the
retracting
arm is operated into a second configuration, the cam presses against the lever
so
as displace the same, and in turn displace the support plate and corresponding
blade into the retracted position.
Preferably also, the biasing means comprise a plurality of springs disposed
along a transversal width of the support plate, in a direction substantially
parallel
to the pivot axis of the hinge supporting the support plate.
Preferably also, the biasing means comprise a casing for containing the
springs within said casing.
Preferably also, the casing comprises first and second parts, said parts
being nestable into one another and being slidably movable with respect to
each
other so as allow the springs to either expand or be compressed within the
casing.
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According to yet another aspect of the invention, there is also provided a
method of operating the above-mentioned blade holding device and/or assembly.
According to yet another aspect of the invention, there is also provided a
kit with components for assembling the above-mentioned blade holding device
and/or assembly.
The objects, advantages and other features of the present invention will
become more apparent upon reading of the following non-restrictive description
of preferred embodiments thereof, given for the purpose of exemplification
only,
with reference to the accompanying drawings.
Brief description of the drawings:
Figure 1 is a side view of a blade holding device according to a preferred
embodiment of the present invention, the blade holding device being shown with
its blade in a contact position with a neighbouring roller.
Figure 2 is another side view of what is shown in Figure 1, the blade of the
blade holding device being now shown in a contact position after the roller
has
decreased in diameter.
Figure 3 is another side view of what is shown in Figure 1, the blade
holding device being now shown with its blade in a retracted position.
Figure 4 is an enlarged view of the blade holding device shown in Figure 1.
Figure 5 is another side view of what is shown in Figure 1, the blade
holding device being now shown provided with retracting means according to a
preferred embodiment of the present invention.
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Figure 6 is another side view of what is shown in Figure 5, the blade
holding device being now shown with its blade in a retracted position via an
operation of the retracting means.
Figure 7 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof being
shown operatively connected between a front portion of the base and a front
portion of the support plate.
Figure 8 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof being
shown with a portion pivotally connected to the base and another portion
operatively connected to a component of a rear portion of the support plate.
Figure 9 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof being
shown with an end in abutment with a L-shaped plate securely connected to the
base of the device, and another end operatively connected to the support plate
via triangular-shaped cams.
Figure 10 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof being
shown with one end connected to a rear portion of the support plate and
another
end connected to a flange positioned above the support plate and removably
connectable onto the base of the blade holding device.
Figure 11 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof being
shown operatively connected between the base and the support plate.
Figures 12 to 14 illustrate different embodiments of biasing means which
could be used with the blade holding device shown in Figure 11.
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Figure 15 is a side view of a blade holding device according to yet another
preferred embodiment of the present invention, the biasing means thereof
comprising a rotatable magazine positioned within a recess of the base, said
magazine comprising a plurality of casings each comprising within a set of
springs of different biasing force.
Figure 16 is an exploded view of a casing with corresponding biasing
means to be contained therein and fasteners according to a preferred
embodiment of the present invention.
Figure 17 is a front plan view of what is shown in Figure 16, the casing,
biasing means, and fasteners being now shown in an assembled configuration.
Figure 18 is a side view of what is shown in Figure 17.
Figure 19 is a front plan view of a casing according to yet another
preferred embodiment of the present invention, said casing including piston
cylinders for allowing the first and second parts of the casing to be slidably
moveable with respect to each other.
Figure 20 is an elevational view of a piston cylinder shown within the
casing of Figure 19.
Figure 21 is an exploded view of what is shown in Figure 20.
Figure 22 is a side view of a casing and corresponding biasing means
contained within according to yet another preferred embodiment of the present
invention.
Figure 23 is an exploded view of what is shown in Figure 22.
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Detailed description of preferred embodiments of the invention:
In the following description, the same numerical references refer to similar
elements. The embodiments and physical dispositions shown in the figures
and/or described herein are preferred, and are used for exemplification
purposes
only.
Moreover, although the present invention was primarily designed for use
with machines and rollers of the pulp and paper industry, it may be used with
other type of objects and in other different fields, as apparent to a person
skilled
in the art. For this reason, expressions such as "roller", "pulp", "paper",
"blade",
etc. used herein should not be taken as to limit the scope of the present
invention
and includes all other kinds of items and/or applications with which the
present
invention could be used and may be useful.
Moreover, in the context of the present invention, the expressions "device",
"system", "holder", and any other equivalent expression and/or compound word
thereof known in the art will be used interchangeably. Furthermore, the same
applies for any other mutually equivalent expressions, such as "assembly",
"apparatus" and "machine", as well as "spring" and "biasing means" for
example,
as also apparent to a person skilled in the art.
In addition, although the preferred embodiment of the present invention as
illustrated in the accompanying drawings comprises various components and
although the preferred embodiment of the blade holding device 1 as shown
consists of certain geometrical configurations as explained and illustrated
herein,
not all of these components and geometries are essential to the invention and
thus should not be taken in their restrictive sense, i.e. should not be taken
as to
limit the scope of the present invention. It is to be understood, as also
apparent to
a person skilled in the art, that other suitable components and cooperations
therein between, as well as other suitable geometrical configurations may be
used
for the blade holding device I and corresponding components according to the
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present invention, as briefly explained and inferred herein, without departing
from
the scope of the invention.
Broadly described, the present invention, as shown in the accompanying
5 drawings, relates to a blade holding device 1 for selectively and adjustably
maintaining a contact pressure onto a neighbouring roller 5, such as the ones
used in machines of the pulp and paper industry, and other like industries. It
is to
be understood that, in the context of the present description, "maintaining a
contact pressure" refers to any suitable interaction (scraping, maintaining,
10 guiding, and the like) which may take place between the blade 3 of the
blade
holding device 1 and the roller 5, as can be easily understood by a person
skilled
in the art.
According to the present invention, and as better shown in Figures 1-3, the
blade holding device 1 comprises a base 7, a hinge 9, a support plate 11, a
blade
3, and biasing means 13. The base 7 may be the same base as that of the
assembly in which the blade holding device 1 is used, or may be a separate
base, and such a base may be fixed to the ground, or moveable with respect
thereto, depending on the particular applications for which the blade holding
device 1 and corresponding assembly are intended for, as also apparent to a
person skilled in the art.
The hinge 7 preferably has first and second components 15, 17, and as
can be easily understood from Figures 1-3, the first component 15 is
preferably
mounted onto the base 7, and the second component 17 is preferably pivotally
moveable with respect to the first component 15 about a pivot axis 19.
According
to a preferred embodiment of the present invention, such a pivot axis 19 is
preferably provided by a pin connecting the first and second components 15, 17
together, as illustrated and as is well known in the art..
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As also better shown in Figure 4, the support plate 11 is preferably
mounted onto the second component 17 of the hinge 9, and thus is pivotally
moveable with respect to the base 7.
From this same Figure 4, it can also be easily understood that the blade 3
is preferably removably mountable onto a front portion 21 of the support plate
11,
the blade 3 being operable between a contact position where the blade 3 rests
against the roller 5 for maintaining the contact pressure (see Figures 1 and
2),
and a retracted position where the blade 3 is drawn away from said roller 5
for
removing the contact pressure (see Figure 3). The ability of the blade holding
device 1 to be operated between these two distinct positions is namely
possible
by means of the hinge 9 and the support plate 11 onto which the blade 3 is
mounted, as shown in Figure 4. Moreover, as will be easily understood from the
following description, the blade holding device 1 according to the present
invention, by virtue of its different components, namely its hinge 9, its
support
plate 11, its biasing means 13, and the like, is enabled to have its blade 3
operated continuously in a contact position, onto the roller 5, and this
throughout
substantial changes in diameter of the roller 5, whether the roller 5 is
increased or
decreased in diameter, as can be easily understood when contrasting Figures 1
and 2, and as also apparent to a person skilled in the art.
Indeed, an important aspect of the present invention resides in that the
blade holding device 1 comprises biasing means 13, the biasing means 13 being
operatively connected between the base 7 and the support plate 11 for biasing
the support plate 11 and corresponding blade 3 into the contact position.
Thus, a
main function of the biasing means 13 is to ensure that the blade 3 which is
mounted onto the support plate 11 is constantly urged onto the roller 5 for
maintaining a contact pressure thereon, that is, to ensure that the blade 3 is
kept
in the contact position. Thus, it may be appreciated that the biasing means 13
according to the present invention may take on various suitable embodiments,
while still carrying out the above-mentioned function. Indeed, Figures 7-11
illustrate a few examples of how the biasing means 13 may be disposed
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otherwise onto the blade holding device 1 according to the present invention.
Different suitable biasing means 13 and dispositions thereof on the blade
holding
device 1, other than the ones described or illustrated herein, may obviously
be
used according to the scope of the present invention, as apparent to a person
skilled in the art.
In order to selectively trigger the blade holding device 1 away from the
contact position, that is, in order to "override" the biasing means 13, the
blade
holding device 1 according to the present invention preferably also comprises
retracting means 23 for operating the support plate 11 and corresponding blade
3
into the retracted position. Similarly to the biasing means 13, the retracting
means
23 according to the present invention may take other suitable embodiments than
those described and illustrated herein, in order to carry out the above-
mentioned
function, as also apparent to a person skilled in the art.
For example, according to a preferred embodiment of the present
invention, the retracting means 23 preferably comprise a hinge 29 similar to
the
above-mentioned first hinge 9. This second hinge 29 preferably has first and
second components 31, 33, the first component 31 being mounted onto the base
7, and the second component 33 being pivotally moveable with respect to the
first
component 31 about a pivot axis 35, as can also be easily understood when
referring to Figures 5 and 6. Once again, the pivot axis 35 preferably takes
the
form of a pin for connecting the first and second components 31, 33 to each
other, as can be easily understood. Moreover, the base 7 of the second hinge
29
is preferably the same base 7 as that of the first hinge 9, but ultimately,
the
second hinge 29 could also be placed onto a separate base, as apparent to a
person skilled in the art.
Moreover, the retracting means 23 also preferably comprise a lever 37,
said lever 37 being mounted onto the second component 33 of the second hinge
29, and thus being pivotally moveable with respect to the base 7, as can also
be
easily understood when referring to Figures 5 and 6. The lever 37 preferably
has
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a front portion 39 cooperating with a rear portion 41 of the support plate 11
for
displacing the same so as to reactively displace the front portion 21 of the
support
plate 11 and corresponding blade 3 away from the roller 5, into the retracted
position, as can be easily understood when contrasting Figures 5 and 6. In
this
particular embodiment, the front portion 39 of the lever 37 is used to push
down
onto a corresponding component provided on the rear portion 41 of the support
plate 21 and thus in turn have said support plate 11 rotated about its
corresponding hinge 9 (or pivot axis 19), so as to raise the front portion 21
of the
support plate 11, and thus raise the blade 3 away from the roller 5. Once
again,
the front portion 39 of the lever 37 and the rear portion 41 of the support
plate 11
may take on various suitable embodiments in order to carry out the above-
mentioned function, as apparent to a person skilled in the art. Moreover, in
the
context of the present description, the words "raising" and "lowering" are
relative,
and may be used conversely, depending at which location the blade holding
device 1 is positioned about the roller 5, as can also be easily understood by
a
person skilled in the art.
According to another preferred embodiment of the invention, the retracting
means 23 further comprise a retracting arm 43, better illustrated in Figures 5
and
6. The retracting arm 43 is preferably pivotally mountable onto the base 7 and
is
preferably provided with a cam 45. The cam 45 is preferably positioned
adjacent
to the lever 37, and it is shaped and sized so that when the retracting arm 43
is
operated into a first configuration, the cam 45 is away from said lever 37, as
better shown in Figure 5, thereby enabling the biasing means 13 to bias the
support plate 11 and corresponding blade 3 into the contact position. In
contrast,
as better shown in Figure 6, when the retracting arm 43 is operated into a
second
configuration, the cam 45 presses against the lever 37 so as to displace the
same, and in turn displaces the support plate 11 and corresponding blade 3
into
the retracted position, as can be easily understood. It is worth mentioning
also
that according to the present invention, the retracting arm 43 may be provided
with a suitable number of cams 45 disposed accordingly along a transversal
width
of the lever 37, in order to appropriately and uniformly press against the
lever 37,
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as can be easily understood by a person skilled in the art. Moreover, instead
of
having a retracting arm 43 and corresponding cam(s) 45 positioned rearwardly
from the support plate 11, and cooperating with said support plate 11 via a
lever
37, a similar type of retracting arm 43 and corresponding cam(s) 45 could be
provided in a front portion of the base 7, and devised so that the cam(s) 45
would
directly press against the support plate 11 so as to operate it into the
retracted
position. In such a case, this embodiment would be preferably provided with a
suitable splashguard so as to avoid that any debris originating from the
roller 5 or
other source may accumulate itself onto the retracting arm 43 and
corresponding
cam system.
Furthermore, as aforementioned, various other suitable embodiments
rather than the above-mentioned retracting arm 43 and cam 45 may be used to
operate the lever (or simply the support plate 11, for that matter) in order
to
trigger the support plate 11 and corresponding blade 3 either into a contact
position, or a retracted position, as also apparent to a person skilled in the
art.
For example, the retracting means 23 could simply consists of the support
plate
11 itself, which would be operated (i.e. pivoted) accordingly, in order to
draw the
blade 3 away from the roller 5, and into the retracted position.
However, it can be easily understood that the above-described retracting
means 23 are advantageous in that they enable to easily, quickly, selectively
and
remotely operate the support plate 11 and corresponding blade 3 between the
contact and retracted positions. It should be also understood that these
retracting
means 23, although advantageous, are not absolutely essential to the
invention,
in that, ultimately, the support plate 11 may act itself as the most basic
retracting
means 23, as aforementioned, that is, the support plate 11 may be operated
manually or mechanically (with pistons, etc.) in order to have the support
plate 11
and corresponding blade 3 operated between contact and retracted
configurations, as can be easily understood by a person skilled in the art.
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According to the preferred embodiment of the present invention, the
biasing means 13 preferably comprise a plurality of springs 47 disposed along
a
transversal width of the support plate 11, in a direction substantially
parallel to the
pivot axis 19 of the hinge 9 supporting the plate 11, as can be easily
understood
5 from Figures 1-11. The biasing means 13 according to the present invention
preferably consists of compression springs 47, for example, and are preferably
disposed in a manner so as to create a constant force on the blade 3 via the
support plate 11, which thus enables the blade 3 to be in continuous contact
with
the roller 5 in a constant manner (contact pressure, preferably), and this for
10 extended periods of time, without maintenance and/or servicing.
According to another important aspect of the present invention, the blade
holding device 1 preferably comprises a casing 49 for containing such springs
47
within the casing 49. This enables namely to avoid having any projecting
15 components of the blade holding device 1 which may adversely cooperate with
other components of the assembly, such as rollers 5, and the like (paper bands
from the rollers 5, etc.), and most importantly, prevents the springs 47 from
being
substantially contaminated from any debris which may be accumulated thereon
from the rollers 5 and other components of the assembly, thereby enabling the
springs 47 to carry out their corresponding biasing action, also for extended
periods of time, and in a substantially trouble-free manner. The springs 47
could
operate without the casing 49, but the presence of such casing 49 is
beneficial,
as explained above and as can be easily understood by a person skilled in the
art.
As can be easily understood from Figures 16-18, the casing 49 according
to the preferred embodiment of the present invention preferably comprises
first
and second parts 51, 53, said parts 51, 53 being nestable into one another and
being slidably moveable with respect to each other so as to compensate for
changes in length of the springs 47 contained within the casing, and thus
enabling the springs 47 to either expand or be compressed depending on the
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positioning (angle, etc.) of the support plate 11 and corresponding blade 3
mounted thereto.
In order to do so, the casing 49 preferably comprises means for ensuring
that the first and second parts 51, 53 are slidably moveable with respect to
each
other, but in such a manner that they do not become detached from one another,
and remained nested into one another. The means achievable for enabling the
above-mentioned features of the first and second parts 51, 53 of the casing 49
can be very diversified, as apparent to a person skilled in the art. Thus,
according
to a preferred and most basic embodiment of the present invention, the first
part
51 of the casing 49 comprises pairs of diametrically opposed holes 55, each
pair
of holes 55 being devised for receiving a corresponding fastener 57, and the
second part 53 of the casing 49 preferably comprises corresponding pairs of
diametrically opposed oblong orifices 59, each pair of oblong orifices 59
being
devised for receiving a fastener 57 of a corresponding pair of holes 55 and
for
thus allowing said fastener 57 to slidably move along said pair of oblong
orifices
59, as can be better understood when referring to Figures 17 and 18. Indeed,
the
fasteners 57 (or pins, etc.) which are inserted into the corresponding pairs
of
holes 55 thus act as stoppers when they abut with the edges of the oblong
orifices 59, and the length of these oblong orifices 59 determine the extent
to
which the springs may either expand or be compressed. Thus, it can be easily
understood by a person skilled in the art that by changing these parameters
(lengths of first and second parts 51, 53 of the casing 49; positioning of
holes 55;
positioning of oblong orifices 59; length of oblong orifices 59; etc.), the
limits of
the array of different pivoting angles achievable by the support plate 11 and
corresponding blade 3 may be altered accordingly.
Alternatively, the blade holding device 1 according to the present invention
may be provided with a casing 49 having first and second parts 51, 53 such as
the ones illustrated in Figures 19-23, wherein the first and second parts 51,
53 of
the casing 49 are deprived of any holes 55 or orifices 59, thereby further
preventing the contamination of the springs 47 contained within the casing 49,
as
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can be easily understood by a person skilled in the art. In this case, instead
of
using the above-mentioned holes 55, orifices 59, and fasteners 57, for
ensuring a
slidable movement between the first and second parts 51, 53, other suitable
means, such as telescopic arms, piston cylinders 71, and the like, as
exemplified
in Figures 19-21, are preferably used, as can be easily understood by a person
skilled in the art. Figures 22 and 23 show views of a casing 49 according to
another preferred embodiment of the present invention, said casing 49
containing
a single spring 47 within. The above-mentioned casings 47 are preferably
provided with suitable sealing means and fasteners 73 for connecting the first
and
second parts 51, 53 in a suitable and sealed manner, as explained herein.
As can be easily understood from the aforementioned, the numbers of
springs 47 to be used, as well as the dimensions thereof, are determined by
the
force which is required for the application for which the blade holding device
1 is
intended for, as apparent to a person skilled in the art. Furthermore, the
casing
49 is preferably devised so that the first and second parts 51,53 thereof are
nested into one another, and sfidably moveable with respect to each other, but
in
a manner that they do not become detached from one another, that is, enabling
them to be operated from top to bottom, that is, enabling them to expand or be
compressed depending on whether the spring(s) 47 contained therein need(s) to
expand or are compressed. Moreover, it should be also understood that,
although
according to the preferred embodiment of the present invention there is a
plurality
of springs 47 contained within a single casing 49, the blade holding device 1
according to the present invention may comprise a plurality of casings 49,
each of
said casings 49 containing either one single spring 47, or a plurality of such
springs 47. As aforementioned, and in order to further illustrate how the
biasing
means 13 may be disposed in different various other suitable dispositions onto
the blade holding device 1 according to the present invention, the biasing
means
13 could for example, comprise a magazine 67 positioned within a recess of the
base 7 and rotatable with respect to said base 7 about a shaft 69. The
magazine
67 would be preferably positioned adjacent to the support plate 11 and
comprise
a plurality of casings 47 extending radially from the shaft 69. The casings 47
CA 02481898 2004-09-16
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would each comprise a set of springs 47 of different biasing force, and each
casing 49 would preferably be interchangeable via a rotation of the magazine
67
about the shaft 69 so as to have a given selected casing 47 operatively
cooperate
between the base 7 and the support plate 11 for biasing the support plate 11
and
corresponding blade 3 into the contact position, as can be easily understood
when referring to Figure 15. Thus, in order to obtain a desired pressure to be
maintained onto the blade 3 via the support plate 11, one would simply have to
rotate the shaft/magazine until the desired position having the corresponding
casing 49 containing the springs 47 of required biasing force, as can be
easily
understood by a person skilled in the art. Furthermore, instead of springs 47
used
as biasing means 13, it is worth mentioning also that according to the present
invention, the biasing means 13 themselves can take on other suitable
embodiments, such as traction springs, tension springs, and the like, as
exemplified in Figures 12-14, so long as these biasing means are capable of
storing somehow a certain amount of potential energy which may in turn be used
for urging the support plate 11 and corresponding blade 3 into the contact
position, as explained hereinabove.
In an attempt to ensure an easy interchangeability of the various
components of the blade holding device 1, the first part 51 of the casing 49
preferably comprises securing means 52 for operatively securing the casing 49
via its first part 51 onto the support plate 11, in a quick and easy manner,
and the
second part 53 of the casing 49 also comprises securing means 54 for
operatively securing the casing 49 via its second part 53 onto the base 7, in
a
similar manner. These securing means 52,54 may take on various different
suitable embodiments, such as tracks, fasteners, and the like, as illustrated
herein and as apparent to a person skilled in the art. The purpose of these
securing means 52,54 is to enable to secure the positioning of either the top
or
bottom portion of the casing 49 onto a corresponding portion of the blade
holding
device 1, typically the support plate 11 and the base 7 respectively, so as to
ensure that the casing 49 and the springs 47 contained therein, namely the
biasing means 13, are positioned and kept into place appropriately, while
CA 02481898 2004-09-16
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enabling them to carry out their corresponding biasing function, so as to urge
the
support plate 11 and corresponding blade 3 into the contact position, as
explained hereinabove.
In a further attempt to ease the interchangeability of the various
components of the blade holding device 1 according to the present invention,
the
front portion 21 of the support plate 11 preferably comprises a support lip
61,
such that an edge of the blade 3 may be slidably insertable into a slot
defined
between the support lip 61 and the support plate 11, as better shown in Figure
4.
Preferably also, the edge of the blade comprises a bulge 63, and the support
lip
61 comprises a rim 65, so that the bulge 63 of the blade 3 be devised for
abutting
with the rim 65 of the support lip 61 and thus prevent the blade 3 from being
easily removed from the slot when inserted therein, as can also be easily
understood when referring to Figure 4. It is worth mentioning though that
according to the present invention, other suitable means for enabling the
blade 3
to be removably, easily, quickly, and securably mounted onto the front portion
21
of the support plate 11 may be used, as also apparent to a person skilled in
the
art.
According to the present invention, the blade holding device 1 and the
corresponding components thereof are preferably made of suitable materials so
as to sustain the loading conditions and the working environments for which
the
blade holding device 1, and corresponding assembly, are intended for, as
apparent to a person skilled in the art. Being typically used in the pulp and
paper
industry, the blade holding device 1 according to the present invention is
preferably designed to be used in an environment at high temperatures, as well
as in very humid conditions. As can be easily understood from the present
description, the blade holding device 1 according to the present invention may
easily replace conventional blade holders, such as the ones of type DST and
KF,
at any given position and location within a conventional assembly or machine.
CA 02481898 2004-09-16
As briefly explained herein, several components of the blade holding
device 1 are completely closed (namely the springs 47 contained within the
casing 49) to prevent that they be obstructed by paste fibers, dust and the
like.
The retracted position for the changing of a blade 3, for example, is
activated by a
5 cam-retractor system complementary to the blade holding device 1. It is also
possible to activate the opening by means of a pressure-rig lever arm or even
by
means of pneumatic actuators, which would cooperate with the support plate 11
in a suitable manner, as explained above and as apparent to a person skilled
in
the art.
As shown in the accompanying drawings, the loading system is mainly
driven by means of biasing means 13, such as compression springs 47 for
example, which are disposed in a manner so as to create a constant force on
the
blade holding device 1, which enables the blade 3 to be in contact with the
roller
5 in a constant manner and this without maintenance, for extended periods of
time of intense service, whereas the loading of the DST blade-holder, for
example, is carried out by means of hoses such as those used for fires, or
rubberized, which dry up and deteriorate after some time. This determining
factor
is a very important point to be considered since the great losses of time
related to
maintenance increase the costs of production of paper considerably.
As briefly explained and illustrated herein, the blade holding device 1
according to the present invention does not require any control panel contrary
to
that of DST blade-holders which requires even more maintenance. Furthermore,
the blade holding device 1 according to the present invention is by far
superior to
the blade-holders of type KF and KB which are rigid and do not offer any
flexibility, that is, cannot match in a uniform manner the surface of the
rollers,
when the latter go through substantial changes in diameter, as is only
possible
with the blade holding device I of the present invention (better appreciated
when
contrasting Figures 1 and 2).
CA 02481898 2004-09-16
21
The blade holding device 1 according to the present invention as well as
the different embodiments thereof can be secured to the frame of the scraper
or
can be mounted onto tracks, in this manner they can be replaced easily by
removing them via the extremities of the scraper.
According to the present invention, and as explained hereinabove, the
loading system is carried out by means of biasing means 13, such as springs
47,
irrespectively of the disposition, the shape, the nature, the dimensions or
the
material used for the manufacturing thereof, and thus any variations from the
present invention, as can be easily understood from the preceeding embodiments
by a person skilled in the art, is considered to be within the scope of the
present
invention.
As mentioned above, according to another aspect of the present invention,
there is provided an assembly comprising a roller and a blade holding device 1
such as the one described herein and such as the one exemplified in the
accompanying drawings. It is to be understood that according to another aspect
of the present invention, there is also provided a method of operating the
above-
mentioned blade holding device I and/or assembly. Furthermore, according to
yet another aspect of the present invention, there is also provided a kit with
components for assembling the above-mentioned blade holding device 1 and/or
assembly.
In regards to the setting of the operation pressures according to a
preferred embodiment of the present invention, one simply has to obtain the
equivalent pressure to that of the PSI required. Pressure tests are preferably
carried out by means of a closed hose at the end linked to a manometer in
which
compressed air is sent and then one adjusts the desired pressure. As can be
easily understood by a person skilled in the art, when the blade holding
device 1
is parallel, the pressure is equivalent to the PSI indicated in the manometer.
Thus, for example: by knowing that three (3) springs of 2" long with a spiral
of
CA 02481898 2004-09-16
22
5/8" and a diameter of 0.080" mounted inside of the compression system body on
a distance of 18" is equivalent to approximately 10 PSI.
As may now be appreciated, the present invention is a substantial
improvement over the prior art in that by virtue of its design and components,
the
blade holding device 1 according to the present invention a) has a loading
system
requiring substantially no maintenance and is thus a revolutionary concept
since
the arrival on the market of the DST blade-holders; similarly to the DST, it
can be
mounted on a plate of about 0.060 inches, but with the added advantage of
enabling different thicknesses, shapes and configurations; b) has a
revolutionary
loading system operated by means of a closed system without maintenance nor
control panel and comprising a flexibility equal and/or superior to that what
is best
done presently in the market; c) requires little or virtually no maintenance
because it does not rely on a hose that may dry up, and offers also a
continuous
contact pressure and does not require any control box; d) is designed for
working
in an environment at high temperatures as well as in very humid conditions; e)
can be provided on conversion sets for replacing DST and KF systems; and f)
can be used on new equipment as well as current equipment. Moreover, the
present invention is also advantageous in that it may be operated manually or
automatically, directly or remotely.
As may now also be better appreciated, the present invention is a
substantial improvement over other related blade holding devices of the prior
art
in that, by virtue of its design and components, the blade holding device 1
according to the present invention a) has a much more simpler design enabling
the components thereof to be easily interchangeable and/or serviced, if need
may
be; b) prevents any debris from the roller 5 from being accumulated onto the
springs 47 because the latter are contained within a corresponding casing 49;
c)
the support plate 11 mounted on the hinge 9 and corresponding blade 3 are thus
intended to follow the roller 5 through a substantial change in diameter of
the
roller 5 (see and contrast Figures 1 and 2), without the need for
repositioning the
blade holding device 5 and/or replacing the blade 3 itself; d) is intended to
have
CA 02481898 2011-05-31
23
its blade 3 maintained onto the roller 5 in a continuous manner, and this
throughout a wide range of roller diameters; and e) has components and
dispositions which enable the blade 3 to be easily, quickly, and adjustably
operated between contact and retracted positions.
The scope of the claims should not be limited by the preferred
embodiments set forth in the examples, but should be given the broadest
interpretation consistent with the description as a whole.
