U.S. patent application number 17/321900 was filed with the patent office on 2022-05-12 for flexible impeller pump for flowable food product.
This patent application is currently assigned to Server Products, Inc.. The applicant listed for this patent is Server Products, Inc.. Invention is credited to Edward Raleigh.
Application Number | 20220145880 17/321900 |
Document ID | / |
Family ID | 1000005629274 |
Filed Date | 2022-05-12 |
United States Patent
Application |
20220145880 |
Kind Code |
A1 |
Raleigh; Edward |
May 12, 2022 |
FLEXIBLE IMPELLER PUMP FOR FLOWABLE FOOD PRODUCT
Abstract
A flexible impeller pump designed for use in dispensing a
flowable food product is disclosed. The flexible impeller pump
includes a cover, impeller assembly and a pump body that are
assembled to create the pump without other separate components. The
components can be permanently connected to each other to create a
disposable pump or can be disassembled for cleaning and reuse. The
impeller assembly includes an impeller shaft and a flexible
impeller molded over the impeller shaft to prevent separation. The
impeller assembly is received within the pump body and the cover is
secured to the pump body. The cover includes a seal that is molded
over the pump body to prevent separation of the seal from the
cover. The impeller shaft extends through the pump body and is
coupled to a drive shaft of an electric motor that is operable to
drive the impeller pump.
Inventors: |
Raleigh; Edward; (Lodi,
WI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Server Products, Inc. |
Richfield |
WI |
US |
|
|
Assignee: |
Server Products, Inc.
Richfield
WI
|
Family ID: |
1000005629274 |
Appl. No.: |
17/321900 |
Filed: |
May 17, 2021 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
63112423 |
Nov 11, 2020 |
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F04C 15/0038 20130101;
F04C 2240/30 20130101; F04C 13/002 20130101; F04C 15/0076
20130101 |
International
Class: |
F04C 2/44 20060101
F04C002/44; F04C 13/00 20060101 F04C013/00 |
Claims
1. A pump operable to pump a flowable food product, comprising: a
pump body including an inlet port, an outlet port and an open
impeller chamber; an impeller assembly configured to be received
within the open impeller chamber, the impeller assembly including
an impeller shaft and an impeller portion having a plurality of
vanes; and a cover member having a body and a seal member, wherein
the cover member is configured to be received and retained on the
pump body such that the seal member is positioned between the cover
member and the pump body.
2. The pump of claim 1 wherein the impeller portion is molded over
an interface section of the impeller shaft.
3. The pump of claim 2 wherein the interface section includes a
plurality of splines that frictionally engage the impeller
portion.
4. The pump of claim 1 wherein the impeller shaft is formed from
molded plastic and the impeller portion is formed from an
elastomeric material.
5. The pump of claim 1 wherein the cover member is mechanically
secured to the pump body to retain the impeller assembly within the
impeller chamber.
6. The pump of claim 5 wherein the cover member is ultrasonically
welded to the pump body.
7. The pump of claim 1 wherein the cover member includes a body
having an annular receiving slot on an inner surface of the body,
wherein the seal member is received and retained within the annular
receiving slot.
8. The pump of claim 7 wherein the seal member is molded within the
annular receiving slot.
9. The pump of claim 1 wherein the impeller shaft includes a drive
shaft portion that extends from the pump body for engagement with a
drive motor
10. The pump of claim 9 wherein the impeller portion includes a
rear seal that surrounds the drive shaft portion and contacts the
pump body when the impeller is received in the pump body.
11. A flowable food product dispenser for dispensing a flowable
food product from a supply of food product, comprising: a pump
operable to pump the supply of flowable food product out of the
dispenser; and a drive motor coupled to the pump and operable to
rotate the pump, wherein the pump comprises: a pump body including
an inlet port, an outlet port and an open impeller chamber; an
impeller assembly configured to be received within the open
impeller chamber, the impeller assembly including an impeller shaft
and an impeller portion having a plurality of vanes; and a cover
member having a body and a seal member, wherein the cover member is
configured to be received and retained on the pump body such that
the seal member is positioned between the cover member and the pump
body.
12. The food product dispenser of claim 11 wherein the impeller
portion is molded over an interface section of the impeller
shaft.
13. The food product dispenser of claim 12 wherein the interface
section includes a plurality of splines that frictionally engage
the impeller portion.
14. The food product dispenser of claim 11 wherein the impeller
shaft is formed from molded plastic and the impeller portion is
formed from an elastomeric material.
15. The food product dispenser of claim 11 wherein the cover member
is mechanically secured to the pump body to retain the impeller
assembly within the impeller chamber.
16. The food product dispenser of claim 11 wherein the cover member
includes a body having an annular receiving slot on an inner
surface of the body, wherein the seal member is received and
retained within the annular receiving slot.
17. The food product dispenser claim 16 wherein the seal member is
molded within the annular receiving slot.
18. The food product dispenser of claim 11 wherein the impeller
shaft includes a drive shaft portion that extends from the pump
body for engagement with a drive motor
19. The food product dispenser pump of claim 18 wherein the
impeller portion includes a rear seal that surrounds the drive
shaft portion and contacts the pump body when the impeller is
received in the pump body.
20. A pump for use in a food product dispenser to pump a flowable
food product, comprising: a pump body including an inlet port, an
outlet port and an open impeller chamber; an impeller assembly
configured to be received within the open impeller chamber, the
impeller assembly including an impeller shaft and an impeller
portion having a plurality of vanes, wherein the impeller portion
is mold over an interface section of the impeller shaft; and a
cover member having a body and a seal member molded into the body,
wherein the cover member is configured to be received and retained
on the pump body such that the seal member is positioned between
the cover member and the pump body.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application is based on and claims priority to
U.S. Provisional Patent Application Ser. No. 63/112,423 filed on
Nov. 11, 2020, the disclosure of which is incorporated herein by
reference.
BACKGROUND
[0002] The present disclosure generally relates to a flexible
impeller pump for use in pumping flowable food products, such as
condiments, from a storage container or bag. More specifically, the
present disclosure relates to a flexible impeller pump that
includes three separate components that can be easily disassembled
for cleaning and reassembled for use or can be disposed of after
use.
[0003] Flowable food products can include a wide variety of
products, such as condiments (i.e. ketchup, mustard, mayonnaise,
tartar sauce, etc.), syrups, dressings, cheeses, fudge, caramel or
other similar food products that can flow and thus be pumped.
Flowable food products can include a wide range of viscosities,
non-Newtonian properties, include small particulates and can be
dispensed in a wide range of temperatures from cold to hot.
Flowable food products can also be heated food products such as
liquid cheese or chilled food products.
[0004] One of the design objectives of the present disclosure was
to develop a pump that was flexible enough in its inherent design
to allow for either cleaning and reuse or disposal after use with
minimal redesign of the pump. The pump of the present disclosure is
designed to have a minimum number of parts to make it as simple as
possible for cleaning. Such a design also lends itself to low-cost
production if automation and material reduction methods are
employed. Depending on material selections to reduce cost (and
possibly product life), the pump of the present disclosure can be
used as a non-cleanable disposable solution should that be desired
for certain applications and food service locations. In such an
exemplary embodiment for a disposable pump, it would be likely to
mechanically secure the cover to the pump body, such as using
ultrasonic welding, making it a permanent assembly.
[0005] The present disclosure utilizes a flexible impeller pump
that is formed from a reduced number of components such that the
pump can be easily assembled and disassembled for cleaning.
Further, the components of the flexible impeller pump are molded in
a way to prevent separation during assembly and disassembly.
SUMMARY
[0006] The present disclosure relates to a flexible impeller pump
for use with a flowable food product dispenser. More specifically,
the present disclosure is directed to a flexible impeller pump that
can be used with a variety of food product dispensers and can be
easily disassembled, cleaned and reassembled.
[0007] The flexible impeller pump includes three primary
components: a pump body, an impeller assembly and a cover. The
three components are assembled together and the entire pump
assembly can be installed in a food product dispenser and driven by
an electric motor to draw a flowable food product through the pump
for dispensing as needed.
[0008] The pump body includes an inlet port and an outlet port
extending from a main body portion. The inlet and outlet ports
include barbs for connection to a flexible line for receiving food
products or dispensing the food product through an outlet conduit.
The barbs on the inlet and outlet ports can also be used to connect
the pump body to one of several different fittings. The pump body
is molded from a plastic material that can be cleaned and
reused.
[0009] The impeller assembly of the flexible impeller pump includes
an impeller shaft and an over molded flexible impeller portion
having a series of impeller vanes. The impeller vanes contact the
inner wall of the main body to create suction to draw the flowable
food products through the pump body.
[0010] The cover of the pump assembly includes a cover member and a
seal over molded into the cover member. The seal cannot separate
from the cover member such that the seal remains a part of the
cover member. The cover is removably attached to the body in an
embodiment in which the pump can be cleaned. In a disposable
embodiment, the cover would be mechanically secured to the pump
body. Such a mechanical connection could be carried out by
ultrasonic welding in one exemplary embodiment, although other
mechanical connections, such as an FDA approved adhesive, are
contemplated.
[0011] The pump assembly is designed to be used with a plurality of
different fittings. The fittings allow the pump assembly to be used
with different supplies of food products, such as food packaging
from different food manufacturers. One example of a common food
package is a 1.5 gallon Cryovac Pouch with a fitment. In another
possible use, the fitment would allow for a direct supply of food
product through a tube or line. Another type of fitting can include
a valve to prevent dripping of the food product during
disconnection of the supply from the pump assembly.
[0012] The flexible pump assembly of the present disclosure allows
for use with a wide range of dispensers and over a wide range of
operating speeds. The elastomeric properties of the impeller vanes
allow for a wider variation in tolerances, which allows for the use
of molding of the components.
[0013] Various other features, objects and advantages of the
invention will be made apparent from the following description
taken together with the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The drawings illustrate the best mode presently contemplated
of carrying out the disclosure. In the drawings:
[0015] FIG. 1 is a schematic illustration of a food product
dispenser including the flexible impeller pump of the present
disclosure;
[0016] FIG. 2 is a front perspective view of the flexible impeller
pump of the present disclosure;
[0017] FIG. 3 is an exploded view of the flexible impeller
pump;
[0018] FIG. 4A is a front perspective view of the impeller shaft of
the impeller assembly;
[0019] FIG. 4B is a rear perspective view of the impeller
shaft;
[0020] FIG. 5A is a front perspective view of the elastomeric
impeller over molded over the impeller shaft;
[0021] FIG. 5B is a rear perspective view of the elastomeric
impeller over molded over the impeller shaft;
[0022] FIG. 6 is a section view of the impeller assembly;
[0023] FIG. 7A is a front view of the cover;
[0024] FIG. 7B is a section view of the cover;
[0025] FIG. 8A is a front view of the cover with the seal member
co-molded with the cover;
[0026] FIG. 8B is a section view of the cover and seal member;
[0027] FIG. 9 is a magnified view of the seal member taken along
line 9-9 of FIG. 8B;
[0028] FIG. 10 is a front perspective view of a modification to the
pump for use with a Cryovac piercing fitting to connect to a food
product pouch;
[0029] FIG. 11A is a front perspective view of the Cryovac piercing
fitting;
[0030] FIG. 11B is a section view of the Cryovac piercing
fitting;
[0031] FIG. 12 is a front perspective view of a second modification
to the pump for use with an integral shut off valve;
[0032] FIG. 13A is a front perspective view of the shut off
valve;
[0033] FIG. 13B is a section view of the shut off valve;
[0034] FIG. 14 is a magnified view of the interaction between the
shut off valve and the flexible impeller pump;
[0035] FIG. 15 is a section view of the interaction shown in FIG.
14;
[0036] FIG. 16 is a front perspective view of a third modification
to the pump for use with a barbed line reducer; and
[0037] FIG. 17 is a front view of the impeller assembly installed
in the pump body.
DETAILED DESCRIPTION
[0038] FIG. 1 illustrates a flowable food product dispenser 2 of
the present disclosure. In the embodiment shown in FIG. 1, a
flowable food product is dispensed from a supply 3 through a spout
4. A container 5 is shown in FIG. 1 as receiving the food product
as the food product is dispensed. However, the food product could
be dispensed directly onto another food item as desired. The supply
of food product could be contained in a flexible bag or package or
could be contained directly within a well or open interior of the
product dispenser 2. In either case, a flexible impeller pump 10 is
connected between the supply 3 and the dispensing spout 4 and is
operable to pump the flowable food product out of the food product
dispenser as desired.
[0039] In the embodiment shown in FIG. 1, the flexible impeller
pump 10 is driven by an electric drive motor 6. The drive motor 6
is connected to a supply of electricity, which could be an internal
battery or a connection to utility power. The drive motor 6 is
preferably a bi-direction electric motor that is operable to drive
the flexible impeller pump 10 in either a forward or reverse
direction.
[0040] The operation of the drive motor 6 is controlled by a
controller 7 positioned within the outer housing 8 of the food
product dispenser. The controller 7 is operable to control the
direction of operation of the drive motor 6, the duration of
operation, the speed of operation and any other parameters needed
to dispense the desired quantity of food product. In the embodiment
shown, the controller 7 is connected to a user input device 9 that
allows a user to initiate and control the dispensing of the food
product. It is contemplated that the input device 9 could be
various different devices. In one exemplary embodiment, the input
device 9 can be a touch-free proximity sensor that can detect the
presence of a hand of the user. Upon detection, the user input
device provides a signal to the controller 7, which can then
control the operation of the pump 10. The user input device 9 could
also be a touch pad, switch, or any other device that allows a user
to indicate that the food product need to be dispensed. The use of
a touch-free sensor allows food product to be dispensed without
physical contact between the user and any portion of the outer
housing 8.
[0041] FIG. 2 illustrates the flexible impeller pump 10 constructed
in accordance with the present disclosure. The flexible impeller
pump 10 is designed for use in a number of installation scenarios,
including dispensing flowable food products from a pouch below the
counter, direct connection of the pump to a pouch of food product,
and integrated into a countertop device with a direct connection to
a pouch of food product. In the embodiment shown in FIG. 2, the
impeller pump 10 includes an inlet port 12 and an outlet port 14.
In the design shown, the impeller pump 10 is reversible such that
either of the two ports 12, 14 could be the inlet or the
outlet.
[0042] In the embodiment shown, the port 12 is designated as the
inlet port while the port 14 is designated as the outlet port. The
impeller pump 10 includes a pump body 16 that is sized to receive
an internal impeller assembly and is enclosed by a cover 18. The
impeller pump 10 can be constructed in an embodiment in which the
cover 18 can be removed for cleaning or in another embodiment in
which the cover 18 is mechanically secured to the pump body 16,
such as by ultrasonic welding or adhesives, and the entire pump
would be disposable after use.
[0043] The impeller is designed to rotate within the pump body 16
to draw food product into the pump body 16 through the inlet port
12 and push the food product out through the outlet port 14.
[0044] FIG. 3 is an exploded view of the impeller pump 10 of the
present disclosure. As illustrated in FIG. 3, the impeller pump 10
includes the pump body 16, the impeller assembly 20 and the cover
18. The impeller pump 10 was designed to reduce the number of
components such that the pump can be easily cleaned after being
broken down into the three main components: the body 16, the cover
18 and the impeller assembly 20. In the embodiment illustrated, the
pump body 16 is molded from an FDA approved plastic material with a
lubrication package. The molded pump body 16 includes an open
impeller chamber 29 that is defined by an interior wall 28 and is
designed to be dishwasher safe while the lubrication package
reduces friction, especially during dry prime when the pump is
filled with air and the product must be drawn from a bag or
reservoir.
[0045] In one exemplary embodiment, the impeller assembly 20 is
formed from an FDA approved thermoplastic vulcanizate (TPV) that is
formed in an over molding process that creates a chemical bond
between the vanes 26 of the impeller and an internal impeller
shaft. The two components that form the impeller assembly 20 are
chemically and mechanically bonded together to create a single
component that will not separate during use and cleaning.
[0046] The cover 18 is also formed from an FDA approved plastic
with a seal member that is over molded or two-shot molded in place
with the main body of the cover 18. Since the seal is permanently
attached to the cover, there is no possibility of losing the seal
or having the seal being misplaced during cleaning. The seal
interacts with the pump body 16 during use to prevent leakage as
the rotating impeller assembly 20 moves food product through the
pump 10.
[0047] As illustrated in FIG. 3, the impeller assembly 20 includes
a drive shaft portion 22 that is designed to extend through the
pump body 16 and receive and engage a motor shaft 24 of a driving
motor. The motor shaft 24 is designed to be rotatable in either
direction such that the connected impeller assembly 20 can be
rotated to draw material in either direction through the pump body
16. The impeller assembly 20 includes a series of flexible vanes 26
that engage the open interior wall 28 of the valve body. In the
embodiment illustrated, each of the vanes 26 is formed from a
flexible material that includes an expanded outer edge 27 that
creates a seal with the inner wall 28 to draw product in through
the inlet port 12 and to push the product out through the outlet
port 14.
[0048] As further illustrated in FIG. 3, the pump assembly includes
a pump retainer bracket 30 that is designed to support the impeller
pump 10. The retainer bracket 30 is an injection molded component
having a pair of spaced receivers 32 that are spaced from each
other to support the pump body 16. In the embodiment shown in FIG.
3, the pump 10 is shown as a configurable pump that can receive a
plurality of different types of fittings.
[0049] FIGS. 4A and 4B illustrate an impeller shaft 34 that forms
part of the impeller assembly. The impeller shaft 34 is a molded
plastic component that includes the drive shaft portion 22 and a
splined interface section 36 having a series of individual splines
38. The splines 38 are designed to be able to transmit torque from
the electric drive motor to the elastomeric impeller that is molded
over the impeller shaft 34. The series of individual splines 38
create a mechanical interface with the elastomeric material that
forms the remainder of the impeller assembly as will be described
below. The impeller shaft 34 includes a stub shaft 40 that is able
to provide rotational support for the end of the impeller shaft
opposite the drive shaft portion 22. The drive shaft portion 22 is
hollow and designed to engage and receive the motor shaft 24, as
previously described, to transmit torque from the stepper motor to
the impeller.
[0050] FIGS. 5A and 5B illustrate the over molding of the
elastomeric impeller portion 42 to the impeller shaft to form the
impeller assembly 20. The elastomeric impeller portion 42 includes
the plurality of vanes 26. The composite impeller assembly 20 is
formed from elastomeric material of the impeller portion 42, such
as thermoplastic vulcanizate (TPV), that chemically bonds to the
polypropylene impeller shaft 34. In addition to the chemical bond,
the mechanical interface created by the series of splines 38 on the
impeller shaft 34 also secures the impeller shaft 34 to the over
molded impeller portion 42.
[0051] As can be seen in FIGS. 5B and 6, a rear seal 44 is formed
as part of the molded impeller portion. The flexible rear seal 44
is designed to create an axial interference fit against the rear
face of the pump housing for sealing the drive shaft portion 22.
The opposite side of the impeller is supported by the stub shaft 40
and seals against the cover member. When the impeller is inserted
into the combination of the cover and body, the impeller vanes 26
flex such that the spring force of the vanes 26 create suction and
the desired pumping action during operation.
[0052] FIGS. 7A and 7B illustrate the main body portion 46 of the
cover 18. The cover 18 includes the main body portion 46 having an
outer surface 48 and an inner surface 50. The inner surface 50
includes an annular receiving slot 52 that is designed to receive
an annular seal. The main body 46 is formed as a molded rigid
plastic part while a seal member 54 is over molded or created in a
two-shot molding process after formation of the main body 46 of the
cover member. The seal member 54 on the cover is molded from the
same TPV material as the impeller portion described previously. The
seal member 54 creates a chemical bond with the main body 46 of the
cover and remains attached to the cover when the cover is removed
from the body of the pump.
[0053] The outer edge 45 of the cover member includes a series of
locking tabs 47 that are spaced equally around the outer
circumference of the cover member 18. The outer surface 48 includes
a protruding engagement fin 49 that extends from the otherwise flat
face surface 51. The engagement fin 49 allows a point of contact
for a user to rotate the entire cover member 18 in either a
counterclockwise locking direction or a clockwise unlocking
direction as show by the indicators 53 molded into the face surface
51.
[0054] When the cover member 18 is installed onto the pump body 16,
the locking tabs 47 are received beneath locking projections 55
formed along the inner wall of the pump body 16, as best understood
in FIG. 3. The cover member 18 is initially installed such that the
locking tabs 47 are spaced from the locking projections 55 and the
cover member 18 can then be rotated in the counterclockwise
direction until the locking tabs 47 are received beneath the
locking projections 55. This engagement holds the cover member in
place in an embodiment in which the cover member 18 is designed for
removal. The cover member 18 can be released and removed by
rotating the cover member 18 in the clockwise direction.
[0055] FIG. 9 provides a magnified view of the seal member 54
formed as part of the co-molding process with the main body portion
46 the cover. The cross section of the seal member 54 includes a
protrusion 56 that is designed to engage an inner surface formed in
the pump body 16. Since the seal member 54 is co-molded with the
remaining portions of the cover, the seal member 54 cannot become
lost or disengaged from the cover.
[0056] FIG. 10 illustrates a first configuration for use of the
impeller pump 10 in dispensing flowable food products. In the
configuration shown in FIG. 10, a piercing fitting 58 is shown
received on the inlet port 12. The piercing fitting 58 is designed
to connect directly to a pouch of a flowable food product utilizing
a fitting associated with the pouch. As an illustrative example,
the food pouch could be a 1.5 gallon Cryovac pouch with the
associated fitting. However, it is contemplated that the piercing
fitting 58 could be designed to interact with fittings from other
manufactures, such as but not limited to VolPak or Scholle. The
piercing fitting 58 can be installed on either side of the impeller
pump 10. Referring back to FIG. 3, the piercing fitting 58 can
include an O-ring 60 or could be utilized without an O-ring
depending upon the embodiment. As can be seen in FIG. 11A, the nose
61 of the piercing fitting 58 includes a pointed outer end 62
designed to pierce a pouch that includes the required mating
fitting. The piercing fitting 58 further includes a locking collar
64 including an open slot 66 designed to engage a lug 68 formed on
the inlet port 12. A similar lug 68 is included on the outlet port
14. The lugs 68 provide a point of attachment for a locking
mechanism to receive one of the fittings as will be described.
[0057] As can be understood in FIG. 3, the nose 69 of the inlet
port 12 and the outlet port 14 each include a barbed fitting
portion 70 that allows the inlet port 12 to securely engage the
piercing fitting 58. Likewise, the outlet port 14 includes a
similar barbed fitting 70 that allows a fitting to be received on
the outlet port 14.
[0058] The associated geometry in all of the fittings is designed
to be fully encapsulating to reduce creep and to enhance strength.
The compression on the conical nose 69 of the pump body is
controlled by accurately locating the surface in the shutoff.
[0059] FIG. 12 illustrates another embodiment for using the
impeller pump 10 of the present disclosure. In this embodiment, the
outlet port 14 is shown receiving a shutoff fitting 72. The shutoff
fitting 72 is also shown in the embodiment of FIG. 3.
[0060] The shutoff fitting 72 is designed such that food product
lines can be connected and disconnected from the pump 10 without
food product leaking. In the embodiment shown in FIGS. 3 and 15, an
O-ring 74 is utilized with the shutoff fitting 72, although the
O-ring 74 could be eliminated. FIGS. 13A and 13B, along with FIG.
13, show additional views of the shutoff fitting 72. As with the
piercing fitting, the shutoff fitting 72 engages the lug 68 formed
as part of the valve body to securely hold the shutoff fitting 72
in place and provide for proper alignment.
[0061] FIG. 16 illustrates yet another contemplated embodiment for
using the impeller pump 10. In the embodiment shown in FIG. 16, a
barbed line-reducer fitting 80 is shown connected to the inlet port
12. The barbed line-reducer fitting 80 is used to reduce the size
of the inlet fitting from the original size to a small, one-eighth
inch diameter outlet fitting 84. Such barbed line-reducer fitting
80 allows for use with a low-viscosity, small-dosing application
wherein the transition to a small diameter line is advantageous.
The line-reducer fitting 80 can be implemented on either side of
the pump 10.
[0062] FIG. 17 is a front view showing the installation of the
impeller assembly 20 within the pump body 16 and the operation of
the flexible vanes 26 to draw liquid food product from the inlet
port 12 to the outlet port 16. As illustrated, the inner wall of
the pump body 16 includes a ramp portion 90 that extends into the
open interior of the pump body. The ramp portion 90 includes a cam
surface 92 that induces bending in the impeller vanes 26 as the
impeller vanes 26 rotate along the cam surface 92. The interaction
between the impeller vanes 26 and the cam surface 92 creates a
suction that draws the liquid fluid product into the inlet port 12
and forces the liquid food product out of the outlet port 16.
[0063] As can be understood by the above description, the flexible
impeller pump of the present disclosure creates a flexible impeller
that is inherently easier to seal due to the elastomeric properties
of the impeller. By comparison to other types of pumps, such as a
gear pump or a vane pump, the flexible impeller pump of the present
disclosure creates sealing that can be accomplished with
interference fits that are within the process capabilities of
injection molding. Further, the injection molding process can bond
the flexible impeller to the rigid drive shaft to accomplish a
reduction in the number of separate parts to be handled during
cleaning. The flexible impeller pump of the present disclosure can
operate over a wide variety of speeds and, due to the inherent
elastomeric properties, generally exhibits less pump slip at low
speeds compared to gear or vane pumps.
[0064] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to make and use the invention. The patentable
scope of the invention is defined by the claims, and may include
other examples that occur to those skilled in the art. Such other
examples are intended to be within the scope of the claims if they
have structural elements that do not differ from the literal
language of the claims, or if they include equivalent structural
elements with insubstantial differences from the literal languages
of the claims.
* * * * *