U.S. patent application number 11/093420 was filed with the patent office on 2006-10-12 for method and apparatus for a linear peristaltic pump.
This patent application is currently assigned to LANCER PARTNERSHIP, LTD.. Invention is credited to Michael T. Romanyszyn, Alfred A. Schroeder.
Application Number | 20060228240 11/093420 |
Document ID | / |
Family ID | 37083326 |
Filed Date | 2006-10-12 |
United States Patent
Application |
20060228240 |
Kind Code |
A1 |
Schroeder; Alfred A. ; et
al. |
October 12, 2006 |
Method and apparatus for a linear peristaltic pump
Abstract
A method and accompanying apparatus dispenses product with a
non-invasive linear peristaltic pump. The linear peristaltic pump
includes a traction plate having a linear portion, a depressor and
a driver. The depressor compresses the product tube between the
linear portion and the depressor, such that an inner passage of the
product tube is substantially sealed. The driver moves the
depressor along the linear portion of the traction plate, such that
the product tube located between the depressor and the linear
portion is compressed along the linear portion. Product in an inner
passage of the product tube is thereby moved or dispensed. Another
embodiment may include depressors attached to belts, wherein
successive depressors may be driven along the linear portion to
dispense or move the product. A method for using a linear
peristaltic pump and the use of a controller to dispense product is
also provided.
Inventors: |
Schroeder; Alfred A.; (San
Antonio, TX) ; Romanyszyn; Michael T.; (San Antonio,
TX) |
Correspondence
Address: |
LAW OFFICES OF CHRISTOPHER L.MAKAY
1634 Milam Building
115 East Travis Street
San Antonio
TX
78205
US
|
Assignee: |
LANCER PARTNERSHIP, LTD.
|
Family ID: |
37083326 |
Appl. No.: |
11/093420 |
Filed: |
March 30, 2005 |
Current U.S.
Class: |
417/476 |
Current CPC
Class: |
F04B 43/1223
20130101 |
Class at
Publication: |
417/476 |
International
Class: |
F04B 43/12 20060101
F04B043/12 |
Claims
1. A linear peristaltic pump, comprising: a traction plate having a
linear portion with an upper end and a lower end; a depressor in
proximity to the upper end of the linear portion, wherein a product
tube containing a product is placed between the linear portion of
the traction plate and the depressor, and further wherein the
depressor compresses the product tube such that an inner passage of
the product tube is substantially shut-off; and a driver, wherein
the driver moves the depressor from the upper end to the lower end
of the linear portion, such that the product tube is compressed by
the depressor along the linear portion of the traction plate and
product in front of the depressor is forced to move with the
depressor, therein dispensing a predetermined amount of the
product.
2. The linear peristaltic pump of claim 1, wherein the driver
comprises a belt attached to the depressor.
3. The linear peristaltic pump of claim 2, wherein the driver
comprises a motor that drives the belt.
4. The linear peristaltic pump of claim 2, wherein the belt
includes multiple depressors that successively compress the product
tube along the linear portion of the traction plate as the belt
rotates.
5. The linear peristaltic pump of claim 1, wherein the linear
peristaltic pump includes multiple depressors to compress the
product tube along the linear portion of the traction plate.
6. The linear peristaltic pump of claim 5, wherein at least one
depressor compresses the product tube at the lower end of the
linear portion of the traction plate.
7. The linear peristaltic pump of claim 6, wherein the depressor
located at the lower end of the linear portion releases the product
tube as the driver moves the depressor located at the upper end of
the linear portion to the lower end of the linear portion.
8. The linear peristaltic pump of claim 4, wherein the depressor is
a roller.
9. The linear peristaltic pump of claim 1, further comprising a
loading position that allows for an increased gap between the
traction plate and the depressor while a product tube is being
installed into the linear peristaltic pump.
10. The linear peristaltic pump of claim 1, wherein the driver
comprises a hydraulic cylinder that moves the depressor along the
linear portion of the traction plate.
11. The linear peristaltic pump of claim 1, wherein the driver
further includes a controller to conduct operations.
12. A method of dispensing product, comprising: depressing a
product tube containing a product against an upper end of a linear
portion of a traction plate using a depressor; and driving the
depressor downward, from the upper end to a lower end of the linear
portion, thereby dispensing a predetermined quantity of
product;
13. The method of claim 12, further comprising: returning the
depressor to the upper end of the linear portion; redepressing the
product tube; and driving the depressor downward.
14. A linear peristaltic pump, comprising: a traction plate having
an upper end, a lower end, and a linear portion therebetween; a
belt assembly having a linear segment in proximity to the linear
portion, wherein a product tube containing a product is placed
between the linear portion of the traction plate and the belt
assembly; a depressor connectable to the belt assembly; and a
driver that rotates the belt assembly, wherein the depressor
compresses the product tube against the upper end of the linear
portion and moves along the linear portion to the lower end of the
linear portion, thereby moving product in front of the
depressor.
15. The linear peristaltic pump of claim 14, wherein the belt
assembly includes multiple depressors.
16. The linear peristaltic pump of claim 15, wherein the depressors
are rollers.
17. The linear peristaltic pump of claim 15, wherein the multiple
depressors successively compress the product tube along the linear
portion of the traction plate as the belt rotates.
18. The linear peristaltic pump of claim 14, wherein the linear
peristaltic pump includes multiple depressors to compress the
product tube along the linear portion of the traction plate.
19. The linear peristaltic pump of claim 15, wherein a depressor
compresses the product tube at the lower end of the linear portion
of the traction plate.
20. The linear peristaltic pump of claim 19, wherein the depressor
located at the lower end of the linear portion releases the product
tube as the driver moves the depressor located at the upper end of
the linear portion to the lower end of the linear portion.
21. The linear peristaltic pump of claim 14, wherein the driver
includes a controller to conduct operations.
22. The linear peristaltic pump of claim 14, further comprising a
loading position that allows for an increased gap between the
traction plate and the depressor while a product tube is being
installed into the linear peristaltic pump.
23. A linear peristaltic pump, comprising: a traction plate having
an upper end, a lower end and a linear portion therebetween; a belt
assembly having a linear segment in proximity to the linear
portion, wherein a product tube containing a product is placed
between the linear portion of the traction plate and the belt
assembly; multiple depressors, wherein the depressors are
connectable to the belt assembly, and further wherein, in a working
position, at least one of the depressors compresses the product
tube at the upper end of the linear portion and at least one of the
depressors compresses the product tube at the lower end of the
linear portion, such that an inner passage of the product tube is
closed at the compression points; and a driver that rotates the
belt assembly, wherein the depressor at the upper end of the linear
portion moves along the linear portion, thereby moving product
along in front of the depressor, and further wherein the depressor
located at the lower end of the linear portion releases from the
product tube.
24. The linear peristaltic pump of claim 23, wherein the depressors
are evenly spaced along the belt assembly.
25. The linear peristaltic pump of claim 23, wherein a successive
depressor engages the product tube at the upper end of the linear
portion as the lower depressor releases from the product tube to
prepare a successive dispense and to protect the product from
contamination.
26. The linear peristaltic pump of claim 23, wherein a depressor
compresses the product tube at the lower end of the linear portion
of the traction plate.
27. The linear peristaltic pump of claim 26, wherein the depressor
located at the lower end of the linear portion releases the product
tube as the driver moves the depressor located at the upper end of
the linear portion to the lower end of the linear portion.
28. The linear peristaltic pump of claim 23, further comprising a
loading position that allows for an increased gap between the
traction plate and the depressor while a product tube is being
installed into the linear peristaltic pump.
29. The linear peristaltic pump of claim 23, wherein the driver
further includes a controller to conduct operations.
30. The linear peristaltic pump according to claim 23, further
comprising: an anti-drag ribbon disposed between the product tube
and the belt assembly, wherein the anti-drag ribbon eliminates the
transmission of vertical force components from the belt assembly to
the product tube.
31. A method of dispensing product, comprising: compressing a
product tube with a depressor at an upper end of a linear portion
of a traction plate; compressing a product tube with a depressor at
a lower end of a linear portion, such that an inner passage of the
product tube is closed off at the compression points; releasing the
depressor located at the lower end from the product tube; and
driving the depressor located at the upper end of the linear
portion along the linear portion from the upper end to the lower
end, thereby dispensing product;
32. The method of claim 31, further comprising: e. depressing the
product tube with a successive depressor when the depressor reaches
the lower end of the linear portion.
33. A linear peristaltic pump, comprising: a traction plate
connectable to a mounting base, wherein the traction plate includes
a linear portion having an upper end and a lower end; a depressor,
wherein a product tube containing a product is placed between the
depressor and the traction plate, such that an inner passage of the
product tube is substantially shut-off, and a driver mounted to the
mounting base and connectable to the depressor, wherein the driver
moves the depressor from the upper end to the lower end of the
linear portion, such that the product tube is compressed by the
depressor along the linear portion and product in front of the
depressor is forced to move with the depressor, therein dispensing
a predetermined amount of the product.
34. The linear peristaltic pump of claim 33, wherein the driver
includes a belt.
35. The linear peristaltic pump of claim 34, wherein the belt
includes multiple depressors.
36. The linear peristaltic pump of claim 35, wherein the multiple
depressors are evenly spaced on the belt.
37. The linear peristaltic pump of claim 34, wherein a belt path
includes a linear segment between a drive gear and an idler
gear.
38. The linear peristaltic pump of claim 37, wherein the linear
segment of the belt is located in proximity to the linear portion
of the traction plate.
39. The linear peristaltic pump of claim 33, further comprising a
loading position and a working position.
40. The linear peristaltic pump according to claim 33, further
comprising: an anti-drag ribbon disposed between the product tube
and the depressor, wherein the anti-drag ribbon eliminates the
transmission of vertical force components from the depressor to the
product tube.
41. The linear peristaltic pump of claim 39, further comprising a
loading position that allows for an increased gap between the
traction plate and the depressor while a product tube is being
installed into the linear peristaltic pump.
42. The linear peristaltic pump of claim 33, wherein the linear
peristaltic pump includes multiple depressors to compress the
product tube along the linear portion.
43. The linear peristaltic pump of claim 42, wherein at least one
depressor compresses the product tube at the lower end of the
linear portion.
44. The linear peristaltic pump of claim 43, wherein the depressor
located at the lower end of the linear portion releases the product
tube as the driver moves the depressor located at the upper end of
the linear portion to the lower end of the linear portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a method and apparatus for
pumping a product and, more particularly, but not by way of
limitation, to pumping a product with a linear peristaltic
pump.
[0003] 2. Description of the Related Art
[0004] In an attempt to remain competitive in the industry of
packaged foods and food type products, retailers are continually
forced to evaluate their packaged foods, as well as their product
dispensers. In attempts to maximize profits, retailers are moving
to less expensive packaging on the food products they use. Many
attempts have been made to simplify package loading and unloading
in a dispenser; however, the added burden associated with complex
packaging is indirectly passed on to the product.
[0005] The least expensive form of packaging currently on the
market is a soft package with a fitting permanently affixed to one
side. The fitting provides the user with a means to connect an
evacuation apparatus to the package. In some instances, a pump is
connected to the pouch, but invasive pumps in food product systems
may create cleanliness problems, as they will require cleaning. As
such, attempts have been made to create a disposable pump that
requires no cleaning. While a pump that requires no cleaning is
convenient, it is also more expensive.
[0006] Non-invasive pumps do not require cleaning, as they never
touch the food product. The most commonly used non-invasive pump is
a peristaltic pump. Use of a peristaltic pump requires a length of
tubing be connected to a product package. The tubing is loaded in a
trough around the perimeter of the peristaltic pump. The
peristaltic pump further includes a set of rollers that move along
the perimeter of the peristaltic pump. As the rollers compress the
tubing, product is displaced when the roller set rotates.
[0007] While retailers like the package cost of a peristaltic type
arrangement, the peristaltic pump is not usable in high accuracy
applications. Problems with the peristaltic pump stem from the
peristaltic pump being circular. As the tubing is wrapped around
the peristaltic pump, the cross-section of tubing changes from a
circular shape to a non-circular shape. Further, as a roller begins
to engage the tubing, the tubing is compressed at the roller
position, as well as in the general area of the roller. The
compression of the tubing is therefore non-linear and inconsistent
as a dispensing means.
[0008] Accordingly, a linear non-invasive peristaltic pump would be
beneficial to retailers and product dispenser manufacturers.
SUMMARY OF THE INVENTION
[0009] In accordance with the present invention, a method and
corresponding apparatus provide a non-invasive linear peristaltic
pump with increased accuracy. Peristaltic pumps currently on the
market are not linear, as the product tube is wrapped around a
rotating carousel and restrained in a circular housing. As the
product tube is stretched around the circular carousel, the inner
passage of the product tube is no longer circular. As such, when
the product tube in the peristaltic pumps is compressed, the output
is non-linear. Therein, peristaltic pumps currently on the market
are not useful in application where high accuracies are
desired.
[0010] The present invention provides a high accuracy peristaltic
pump with a linear stoke. A linear peristaltic pump includes a
traction plate with a linear portion, at least one depressor and a
driver. The depressor compresses the product tube between the
linear portion and the depressor, such that an inner passage of the
product tube is substantially sealed. The driver moves the
depressor along the linear portion of the traction plate, such that
a product tube located between the depressor and the linear portion
is compressed along the linear portion. Another embodiment may
include depressors attached to belts, wherein successive depressors
may be driven along the linear portion to dispense or move product.
Still another embodiment may include the use of a controller to
conduct the dispensing operations.
[0011] It is therefore an object of the present invention to
provide a linear, non-invasive pump for dispensing product.
[0012] It is further an object of the present invention to depress
a product tube along a linear portion of a traction plate, such
that product is moved in front of the depressor.
[0013] It is still further an object of the present invention to
provide successive depressors along a linear path to dispense
substantially any amount of product.
[0014] It is still yet further an object of the present invention
to provide a method of dispensing product using the linear
peristaltic pump.
[0015] Still other objects, feature, and advantages of the present
invention will become evident to those of ordinary skill in the art
in light of the following.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 illustrates a first embodiment of a linear
peristaltic pump.
[0017] FIG. 2 illustrates a loading position of the linear
peristaltic pump according to the first embodiment.
[0018] FIG. 3 defines the stroke of the linear peristaltic pump
according to the first embodiment of the invention.
[0019] FIG. 4 illustrates a working position of the linear
peristaltic pump according to the first embodiment of the
invention.
[0020] FIG. 5 illustrates the end of the working stroke with a
product tube in place.
[0021] FIG. 6 provides a method flowchart for using the linear
peristaltic pump according to the first embodiment.
[0022] FIG. 7 illustrates a linear peristaltic pump assembly
according to a second embodiment.
[0023] FIG. 8 provides an exploded view of the linear peristaltic
pump assembly according to the second embodiment.
[0024] FIG. 9a illustrates a right side view of the linear
peristaltic pump according to the second embodiment.
[0025] FIG. 9b provides a section view through the centerlines of
the shafts according to the second embodiment.
[0026] FIG. 10 illustrates the linear peristaltic pump in use with
a product tube according to the second embodiment.
[0027] FIG. 11a is a left-side view of the linear peristaltic pump
according to the second embodiment.
[0028] FIG. 11b is a section view through the centerline of the
belt assembly according to the second embodiment.
[0029] FIG. 12 is a method flowchart illustrating the steps for
using the linear peristaltic pump according to the second
embodiment.
[0030] FIG. 13 provides a perspective view of the linear
peristaltic pump including an anti-drag ribbon according to a third
embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0031] As required, detailed embodiments of the present invention
are disclosed herein; however, it is to be understood that the
disclosed embodiments are merely exemplary of the invention, which
may be embodied in various forms. It is further to be understood
that the figures are not necessarily to scale, and some features
may be exaggerated to show details of particular components or
steps.
[0032] The preferred embodiment is a method and apparatus for
dispensing products using a peristaltic pump that includes a
straight or linear segment to provide a more consistent dispense.
The linear peristaltic pump includes provisions for metering fluid
products or semi-fluid products. The linear peristaltic pump is
non-invasive to the product. As such, it may be utilized on wide
ranges of food products and food product dynamics. Low viscosity
products may flow to the pump freely; however, semi-viscous and
high viscosity products may be dispensed with the assistance of an
evacuation device to achieve acceptable evacuation parameters. The
linear peristaltic pump is able to engage the product packaging
used in existing peristaltic pump applications.
[0033] In the simplest form, a linear peristaltic pump 300 includes
a traction plate 312, a depressor 356 and a driver 330, as shown in
FIG. 1. The traction plate 312 includes an upper end 313, a lower
end 314 and a linear portion 311 between the upper end 313 and
lower end 314. The traction plate 312 may be fixtured to any
suitable bearing surface such as a dispenser or a tabletop. The
depressor 356 is located near to the upper end 313 of the linear
portion 311 of the traction plate 312 at a distance sufficient to
allow placement of a product tube 310 between the depressor 356 and
the linear portion 311 of the traction plate 312, as shown in FIG.
2. The depressor 356 is oriented substantially perpendicular to the
linear portion 311 of the traction plate 312. The driver 330 is
connected to the depressor 356. The driver 330 is any device
suitable to deliver at least one linear translation of the
depressor 356 along the linear portion 311 of the traction plate
312, such as a linear actuator or a hydraulic cylinder, which may
or may not be used in conjunction with a control system including a
controller 303. The stroke or linear movement in this embodiment
can be described as moving the depressor 356 from point A to point
B as shown in FIG. 3.
[0034] The linear peristaltic pump 300 includes a loading position
and a working position, wherein the depressor 356 and the traction
plate 312 cooperate to expand or reduce the gap therebetween. In
the loading position, the depressor 356 may or may not be in
contact with the traction plate 312 or the product tube 310. A
slight pressure on the product tube 310 during loading may be
desirable to maintain feature locations. In the working position,
the depressor 356 compresses the product tube 310 such that the
inner passage is sealed off at the depressor 356 compression point
as shown in FIG. 4. While this embodiment shows the depressor 356
compression point at the upper end of the linear portion 311 of the
traction plate 312, the depressor 356 compression point may be at
any point on the linear portion 311, while in a waiting mode.
Movement from the working position to the loading position may be
accomplished manually or automatically depending on the
application. The linear peristaltic pump 300 may also include a
valve that operates in tandem with the depressor 356 in sealing the
product tube 310.
[0035] In operation, a product tube 310 is loaded into the gap, and
the linear peristaltic pump 300 is moved into the working position,
therein compressing the product tube 310 between the depressor 356
and the traction plate 312. Upon a dispense, the driver 330 forces
the depressor 356 downward along the linear portion 311 of the
traction plate 312. The depressor 356 therein continuously applies
pressure to the product tube 310 as it moves from the upper end 313
to the lower end 314 of the linear portion 311. As the depressor
356 is moved toward the lower end 314 of the linear portion 311, a
predetermined quantity of product in the product tube 310 is forced
downward in front of the depressor 356. The driver 330 then
releases the product tube 310 and returns the depressor 356 to the
upper end 313 of the linear portion 311 of the traction plate 312.
The product tube 310 is again depressed at the upper end 313 of the
linear portion 311, therein closing off the inner passage of the
product tube 310. This process may be repeated as desired to
dispense a desired amount of product. The continued compression of
the product tube 310 along a linear path provides a more consistent
displacement of product, as the tube 310 and its inner passage are
not stretched around a curved surface. This process may be used to
evacuate product from a package or to move product to remote areas
through the use of a hose.
[0036] FIG. 6 provides a method flowchart for using the linear
peristaltic pump 300 with a control system and a controller 303.
The process commences with step 40, wherein a product tube 310 is
loaded into the gap between the depressor 356 and the linear
portion 311 of the traction plate 312. In step 45, the linear
peristaltic pump 300 is set to a working position, wherein the
driver 330 forces the depressor 356 to compress the product tube
310 against the upper end 313 of the linear portion 311 of the
traction plate 312. Once compressed, the inner passage of the
product tube is sealed at the depressor 356 compression point. The
process then moves to a wait state, step 47. Step 50 provides for a
dispense signal check. If a dispense signal has not been recorded,
the process moves back to step 47 to wait another interval. If a
dispense signal has been recorded in step 50, the process moves to
step 55, wherein the driver 330 moves the depressor 356 downward
along the linear portion 311 of the traction plate 312. In step 60,
the driver 330 returns to the starting position at the upper end
313 of the linear portion 311 of the traction plate 312. In step
65, the controller 303 determines whether enough product has been
dispensed. If more dispensing is required, the process moves back
to step 55, wherein the driver moves the depressor 356 from the
upper end 313 to the lower end 314 of the linear portion 311. If no
further dispensing is required, the process will move to step 66
where the dispense ends, and the controller 303 moves back to step
47, where it waits for a dispense signal.
[0037] While the depressor 356 compression point has been shown to
rest at the upper end 313 of the linear portion 311, it may also be
arranged such that the compression point is at the end of the
dispense stroke. A compression point at the end of the dispense
stroke leaves minimal product in front of the compression point,
therein protecting the product in the tube behind the compression
point from exposure to contaminants. Alternatively, a valve may be
included to assist the depressor 356 in maintaining the product
tube 310 closed and therein sealed from exposure to
contaminants.
[0038] While this embodiment has been shown with a single depressor
356, it should be noted that more than one depressor 356 may be
used to provide redundant seals or subsequent passes along the
linear portion 311 of the traction plate 312. Multiple depressors
356 may or may not be connected together through the use of a belt
or chain. A belt arrangement with multiple depressors 356 may
provide a multitude of dispenses at will through the use of a
controller and motor combination. The belt may essentially be any
number of links, however, once a circular pattern is achieved,
virtually any desired dispense amount may be achieved.
[0039] While this embodiment has been shown with a cylindrically
shaped depressor 356, the shape of the depressor 356 may deviate
based on the drive system device or product and tube choices.
[0040] As shown in FIGS. 7-12, a linear peristaltic pump assembly
100 includes a mounting frame assembly 110, a motor assembly 120
and a drive belt assembly 130. The linear peristaltic pump assembly
100 may or may not be used with a control system including a
controller 103. The mounting frame assembly 110 includes a mounting
base 111 and a traction plate 112. The traction plate 112 includes
an upper end 106, a lower end 107 and a linear portion 108
therebetween. The traction plate 112 may be mounted to the mounting
base 111 using any suitable means, such as screws 113 or may be
hinged to provide a release mechanism. The mounting base 111 may be
of any suitable material of sufficient strength to support the
linear peristaltic pump assembly 100, either stand-alone or may be
mounted inside of a product dispenser.
[0041] The base 111 includes a first face 115 and a second face
116, directly opposed to the first face 115. A first shaft aperture
114 and a second shaft aperture 118 extend from the first face 115
to the second face 116. The base 111 further includes a groove 117
having an inner periphery 197 and an outer periphery 198 on the
first face 115 surrounding the shaft apertures 114 at a
predetermined radius. The groove 117 has a depth suitable to
provide restraint to captured dowel pins, such that the dowel pins
are able to move along the groove 117. Each shaft aperture includes
a counterbore 119 on the second face 116 concentric to the shaft
aperture to accept a bearing 123 and a tolerance ring 124.
[0042] The motor assembly 120 includes a motor 121, a drive shaft
122, an idler shaft 125, the bearings 123, the tolerance rings 124
and a plurality of screws 127. The motor 121 includes a motor shaft
128 and a mounting plate 129. The tolerance rings 124 are shaped to
fit in the counterbore 119. The bearings 123, having an inner
periphery 145 and an outer periphery 144, are then pressed into the
counterbores 119 in the first shaft aperture 114 and second shaft
aperture 118, such that the outer periphery 144 engages the
counterbores 119. The drive shaft 122 includes a bearing surface
150 adjacent to a shoulder 152. The shoulder 152 includes an
aperture 151 to accommodate a setscrew 126. The drive shaft 122
further includes an aperture 153 to accept the motor shaft 128 and
a drive portion 170 that includes a machined flat 171 for
additional bearing surface. The motor shaft 128 includes a machined
flat 149 to engage the setscrew 126. The drive shaft 122 still
further includes a machined flat 148 for additional load bearing
capacity and an end bearing surface 147 at the tip.
[0043] The motor shaft 128 is housed in the aperture 153 upon
engagement with the drive shaft 122. The motor shaft 128 is secured
to the drive shaft 122 with the setscrew 126. The drive shaft 122
is pressed into the bearing 123 in the base 111, such that the
bearing surface 150 presses slightly into the inner periphery 145
of the bearing 123. The motor 121 is secured to the base 111 with a
plurality of screws 127 that pass through a set of mounting holes
131 in the mounting plate 129 to engage mounting holes 146 in the
second face 116 of the base.
[0044] The drive belt assembly 130 includes bottom endcaps 137, top
endcaps 138, pin guides 134, a belt link assembly 135, drive gears
136, an intergear support guide 139 and a cover plate 140. The belt
link assembly 135 includes belt links 154, dowel pins 155 and
rollers 156. The belt links 154 each include a link body 160, a
first end 157, a second end 158 and link tabs 163 and 168. The link
tabs 163 and 168 lie perpendicular to the plane of the link body
160. Link tabs 163 protrude from the first end 157 and link tabs
168 protrude from the second end 158 of the link body 160. The link
tabs 163 include an aperture 164 on each link tab 163 on the first
end 157 and an aperture 167 on each link tab 168 on the second end
158. A radial edge 165 surrounds the apertures 164 and 167. On the
first end 157, the link tabs 163 are oriented such that the
apertures 164 are coaxial. The spacing between the link tabs 163 on
the first end 157 is such that the roller 156, having an axial
aperture 166, fits between the link tabs 163. The roller 156 is
oriented coaxially to the apertures 164. On the second end 158, the
spacing between the link tabs 168 allows the roller 156 and the
link tabs 163 from the first end 157 of another belt link 154 to
align between the link tabs 168. Once aligned, the dowel pin 155 is
inserted through the aligned apertures. Illustratively, the dowel
pin 155 passes through the aperture 167 from the second end 158,
the aperture 164 from the first end 157, the axial aperture 166 of
the roller, the second aperture 164 from the first end 157 and the
second aperture 167 from the second end 158. The dowel pins 155 are
centered in the apertures and protrude from the connection. In this
type of arrangement, the belt links 154 may cooperatively engage to
form a belt type arrangement and individually rotate about the
dowel pins 155. While this embodiment has been shown with five belt
links 154, it should be clear to one skilled in the art that the
quantity of belt links 154 in the belt link assembly 135 may
vary.
[0045] The belt links 154 further include a drive surface 159
having a plurality of tread protrusions 161 aligned parallel to the
axis of the installed dowel pins 155. The tread protrusions 161
engage the drive gears 136. In this embodiment, the drive gears 136
are injection-molded components used to transfer the force applied
from the drive shaft 122 to the drive belt assembly 135. The drive
gears 136 include a shaft aperture 169 containing a flat 174 to
engage the machined flat 148 of the drive shaft 122. The drive
gears 136 include a circular outer perimeter 172 with radial insets
173, three in this preferred embodiment, to provide clearance for
the rollers 156 on assembly. The drive gears 136 further include
tread 175 on the outer perimeter 172 to engage the drive surface
159 of the belt links 154. As the drive gears 136 are injection
molded, the component is cored to produce a relatively consistent
wall thickness. As such, inner core pockets 176, substantially
symmetrical, exist on both ends of the drive gears 136. The inner
core pockets 176 engage the endcaps 137 and 138.
[0046] In this preferred embodiment, the endcaps 137 and 138 are
injection-molded components. The endcaps 137 and 138 include an
outer periphery 178 and an aperture 179 to provide passage for the
drive shaft 122. Two endcaps are required per drive gear 136, the
top endcap 137 and the bottom endcap 138. The endcaps 137 and 138
include a gear side 180 and a guide side 181. The gear side 180
includes a protrusion 199 in the shape of the inner core pocket 176
of the drive gear 136 that is used to align the endcaps 137 to the
drive gear 136. The outer periphery 178 of the endcaps 137 and 138
further includes radial insets 182 to provide clearance for the
dowel pins 155. The guide side 181 of the endcaps 137 and 138
includes a cylindrical protrusion 183 that is used to engage the
pin guides 134.
[0047] The pin guides 134 are thin, flat components used to impart
correct spacing between the drive gears 136. The pin guides 134
include two apertures 184, designed to fit over the cylindrical
protrusion 183 of each endcap 137 and 138. The pin guides 134
further include alignment apertures 185 to accept an alignment pin
188 and a clearance aperture 186 to accept a screw 142. An outer
periphery 206 of the pin guide 134 mirrors an inner periphery 197
of the groove 117 in the base 111.
[0048] The intergear support guide 139, in this preferred
embodiment, is an injection-molded component used to maintain the
spacing between the linear peristaltic pump components. The
intergear support guide 139 includes a raised section 200 with a
symmetrical flange 201 at each end. The intergear support guide 139
includes a scalloped section 202 on each side to provide clearance
for the rotating gears 136. The intergear support guide 139 further
includes a flat 205 on the edge of each flange 201. The intergear
support guide 139 still further includes two apertures 204 for
alignment pins 188 and a plurality of apertures 203 to accept the
fasteners 142.
[0049] The cover plate 140 captivates the drive belt assembly 130
and associated components when the fasteners 142 are secured. The
cover plate 140 is an injection-molded component having a gear side
189 and an outer side 190. The gear side 189 of the cover plate 140
includes a groove 191 symmetrical to the groove 117 in the base
111. The groove 191 surrounds two blind holes 192 on the gear side
189 of the cover plate 140. The blind holes 192 are used to accept
a bearing 193. The cover plate 140 further includes alignment
apertures 194 and a fastener aperture 195.
[0050] On assembly, the bearings 123 and the tolerance rings 124
are pressed into the base 111. The idler shaft 125 is then pressed
into the bearing 123 in the base 111. The motor shaft 128 is
inserted into the aperture 151 in the drive shaft 122 and secured
with the setscrew 126. The motor assembly 120 is then pressed into
the bearing 123 which was previously pressed in the base 111. The
mounting plate 129 is then secured to the base 111 using screws
127. Once assembled, the drive shaft 122 and the idler shaft 125
protrude through the first face 115 of the mounting base 111. The
alignment dowel pins 188 are then pressed into the alignment pin
aperture 187 on the first face 115 of the base 111.
[0051] Once the motor assembly 120 has been assembled to the
mounting frame assembly 110, the spring washers 143 may be
assembled onto the protruding shafts. One of the pin guides 134 is
then assembled on the alignment pins 188, followed by the standoff
139. An endcap 138 is then added to each shaft 122 and 125, such
that the cylindrical protrusions 183 fit within the aperture 184 of
the pin guide 134. The gears 136 slide onto the shafts 122 and 125
and engage the gear side 180 of the endcaps 137 and 138.
Installation of the gears 136 is followed by the installation of
the belt link assembly 135. The belt link assembly 135 can now be
placed around the gears 136 and the standoff 139, such that the
drive surface 159 of the belt links 154 engages the treads 175 of
the gears 136, and the radial insets 173 of the gears 136 engage
the rollers 156. When seated properly, the protruding dowel pins
155 of the belt link assembly 135 engage the groove 117 located in
the base 111.
[0052] Installation of the belt link assembly 135 is followed by
the installation of the top endcaps 138. The gear side 189 of the
top endcap 137 engages the innercore pockets 176 of the gears 136.
The radial insets 173 and 182 of the endcaps 137 and 138 engage the
belt link assembly pins 155 to maintain tension in the belt link
assembly 135. The pin guide 134 is then installed such that the
alignment apertures 185 fit around the alignment pins 188. In this
arrangement, the cylindrical protusions 183 of the top endcaps 138
fit within the apertures 184 of the pin guide 134, thereby
providing additional alignment. Additionally, the pin guide 134
fits wholly within the dowel pins 155 of the belt link assembly 135
to provide support for the dowel pins 155 along the outer periphery
206. The installation of the pin guide 134 is followed by the
installation of the washers 143 onto the shafts 122 and 125.
[0053] The bearings 193 are pressed into the blind holes 192 in the
cover plate 140. The assembled coverplate 140 and bearings 193 are
then pressed onto the protruding shafts 122 and 125 and the
alignment pins 188. Once pressed into position, the protruding
dowel pins 155 of the belt link assembly 135 engage the groove 191
in the cover plate 140. Fasteners 142 are used to restrain the
assembly. In this arrangement, as the motor 121 is powered, the
gears 136, and ultimately the belt assembly 130 are still able to
rotate.
[0054] In operation, the linear peristaltic pump may or may not be
used with a controller 103. Embodiments without a controller 103
would require manual activation. The motor 121 is powered by an
electrical power source (not shown). When the motor 121 is powered,
the motor shaft 128 rotates, thereby rotating the driveshaft 122 in
the bearing 123. Rotation of the driveshaft 122 forces the drive
gear assembly 235 to turn. Rotation of the drive gear assembly 235
forces the belt link assembly 135 to rotate about the drive gear
assembly 235. As the belt link assembly 135 rotates, it forces the
idler gear assembly 230 to rotate. With the belt link assembly 135
being driven by the drive gear assembly 235, the dowel pins 155 in
the belt link assembly 135 are forced to move along the groove 117
in the base 111 and the groove 191 in the cover plate 140. The pin
guides 134 are sized such that the dowel pins 155 may ride on the
outer periphery 206 of the pin guides 134. This arrangement
provides the dowel pins 155 with support when not supported by the
endcaps 137 and 138, such as for example when the dowel pins 155
are passing over the flat area between gear assemblies 235 and
230.
[0055] The flat area between the drive gear 136 and the idler gear
236 provides the rollers 156 in the belt link assembly 135 with a
linear translation on the flat segment of the belt link assembly
135 located adjacent to the linear portion 108 of the traction
plate 112. The traction plate 112, having a working position and a
loading position, may be hingedly connected to the assembly. In the
working position, the traction plate 112 cooperatively works with
the rollers 156 of the belt link assembly 135 to maintain a
predetermined spacing between the rollers 156 and the linear
portion 108 of the traction plate 112. In the loading position, the
gap between the traction plate 112 and the rollers 156 may be
enlarged slightly to provide the user with the ability to load a
product tube 210 into the gap.
[0056] Once the product tube 210 is loaded into the gap, the
traction plate 112 is moved to the working position, wherein the
working position provides for compression to the point of sealing
the inner passage of the product tube 210 at the rollers 156. In
this embodiment, the depressors are rollers 156 connected to a
belt. Two rollers 156 initially compress the product tube 210, one
at the upper end 106 of the linear portion 108 and one at the lower
end 107 of the linear portion 108. In this arrangement, as the
motor 121 is powered, the drive belt assembly 130 begins to move
along the grooves 117 and 191. As the belt assembly 130 moves
around the grooves 117 and 191, the rollers 156 are forced to
follow, thereby compressing the product tube 210 and moving
linearly along the product tube 210 and the linear portion 108 of
the traction plate 112.
[0057] As the rollers 156 roll along the product tube 210, the
product tube 210 is compressed by the upper roller 156 throughout
the duration of the roll along the product tube 210. Moving the
compression point of the product tube 210 along the linear portion
108 of the traction plate 112, illustratively from the upper end
106 to the lower end 107 of the linear portion 108, forces product
located in the inner passage of the product tube 210 to be moved
along in front of the roller 156. The roller 156 at the lower end
107 of the linear portion disengages from the product tube 210 when
the belt assembly 130 begins to rotate. A subsequent roller 156
engages the product tube 210 at the upper end 106 of the linear
portion 108, essentially simultaneously with the disengagement of
the lower roller 156. This process is repeated with each roller 156
as the motor 121 continues to drive the belt assembly 130. If the
motor 121 is stopped, at least one of the rollers 156 is engaged
with the product tube 210 to provide a hermetic seal for the
contents of the product tube 210 and/or a package 220.
[0058] FIG. 12 provides a method flowchart for using the linear
peristaltic pump 100 with a controller 103. The process begins with
step 10, wherein the traction plate 112 is moved to the loading
position to accept a product tube 210. The product tube 210 does
not necessarily have to be part of the package 220, as it may be
connected to the package 220 as required. Once the traction plate
112 is in the loading position, the product tube 210 may be
inserted parallel to the flat portion of the belt link assembly
135, between the belt assembly 130 and the linear portion 108 of
the traction plate 112. The process continues with step 12, wherein
the linear peristaltic pump 100 is changed to the working position.
In the working position, the product tube 210 is compressed by two
rollers, such that the inner passage is closed at the compression
points. A first end 211 of the product tube 210 may be connected to
a product source 220, either remote or in the general area, and a
second end 212 may be fixtured to provide a dispensing outlet.
[0059] Once properly routed in the working position, the linear
peristaltic pump 100 may be primed, step 14, by the operator to
ensure that product will flow when the motor is powered. Once
primed, the process moves to step 15, wherein the controller 103 is
in a wait state. At a predetermined time interval, the controller
will check for a dispense signal as shown in step 20. If a dispense
signal has not been recorded, the process will return to step 15,
wherein the controller 103 will wait for another time interval. If
a dispense signal has been recorded in step 20, the process moves
to step 25, wherein the driver rotates the belt along the linear
portion 108 of the traction plate 112 from the upper end 106 to the
lower end 107 of the linear portion 108 of the traction plate 112.
In this step, the roller 156 compressing the product tube 210 at
the upper end 106 of the linear portion 108 is forced downward
along the linear portion 108 and the product tube 210, thereby
dispensing product. Once the belt rotates, the roller 156 initially
at the lower end 107 of the linear portion 108 begins to move
around the drive gear assembly 235 and begins to release from the
product tube 210, and eventually fully releases from the product
tube 210. As the lower roller 156 releases the product tube 210,
the succeeding roller 156 in the belt assembly 135 compresses the
product tube 210 at the upper end 106 of the linear portion 108.
Therein, at least one roller 156 is compressing the product tube
210 at all times. After the dispense, the process moves to step 30,
wherein the controller 103 determines if more repetitions are
required. If more repetitions are required, the process moves to
step 25, and the process continues for another cycle. If the proper
amount of product has been dispensed, no further repetitions will
be required, and the process moves to step 35, where the dispense
ends. The process then moves to step 15, wherein the controller 103
waits for another dispense signal.
[0060] As shown in FIG. 13, a linear peristaltic pump 400 may be
identical to the linear peristaltic pump 100 of the first
embodiment, and accordingly, like parts have been numbered with
like numerals. The linear peristaltic pump 400 may further include
a ribbon support 405, and an anti-drag ribbon 410. In this
embodiment, the ribbon support 405 may be any device suitable for
restraining the anti-drag ribbon 410. Illustratively, a dowel pin
may be secured to the first face 115 of the base 111. The ribbon
support 405 should extend slightly beyond the rollers 156 to
provide adequate engagement length for the anti-drag ribbon 405.
The anti-drag ribbon 405 may be any device suitable for stopping
the transfer of the vertical force components from the rollers 156
to the product tube 210. In this embodiment, the anti-drag ribbon
410 is constructed from a thin sheet of stainless steel, however,
one of ordinary skill in the art will recognize that other
materials may be utilized, including friction resistant plastics,
other metal alloys, and the like.
[0061] In use, the ribbon support 405 is secured to the base 111 to
provide a locating point for the anti-drag ribbon 405. Once
attached, the anti-drag ribbon 405 may hang between the rollers 156
and the traction plate 112. Upon loading of the product tube 210
into the linear peristaltic pump 400, the anti-drag ribbon 405 lies
between the product tube 210 and the drive belt assembly 130, and
isolates the product tube 210 from the vertical motion of the
rollers 156. In place, the rollers 156 directly contact the
anti-drag ribbon 405, and the anti-drag ribbon 405 deflects to
apply a horizontal force component to the product tube 210.
Further, as the rollers 156 move downward, the anti-drag ribbon 405
remains in the same position, thereby eliminating the possibility
of the product tube 210 being dragged downward. Accordingly, the
product tube 210 experiences predominantly horizontal force
components. All other operations of the linear peristaltic pump 400
are identical in form to the linear peristaltic pump 100, and
therefore will not be further discussed.
[0062] Although the present invention has been described in terms
of the foregoing preferred embodiment, such description has been
for exemplary purposes only and, as will be apparent to those of
ordinary skill in the art, many alternatives, equivalents, and
variations of varying degrees will fall within the scope of the
present invention. That scope, accordingly, is not to be limited in
any respect by the foregoing detailed description; rather, it is
defined only by the claims that follow.
* * * * *