Piston pump for easily damaged products

An improved pumping device for delicate or easily damaged products is provided with a hopper, or other system for holding the products, and at least one, and preferably two, synchronized piston pumps positioned proximate to the bottom of the hopper. The piston pumps displace the product from the interior of the hopper into a consolidating feed manifold where the product is then dispensed through a discharge conduit into suitable receptacles. Each of the piston pumps preferably includes a pump cylinder with a fixed, elongated, cylindrical sleeve housing and an elongated rotatable cylindrical sleeve positioned within the sleeve housing, both enclosing a piston chamber. A first longitudinal opening or access port is formed in the fixed sleeve housing and a corresponding second longitudinal opening or access portion is formed in the rotatable sleeve. The rotatable sleeve is reversibly movable about the central axis of the piston chamber from a first, open position with the first and second access ports in register to a second, closed position with the access ports out of register. The edges of the sleeve access ports may be sharpened and angularly disposed to shear portions of product remaining within the hopper and to disperse those portions as the rotatable sleeves are moved. The device, in addition, may be provided with a agitator to disperse the product within the hopper and to urge product towards the piston pumps.

FIELD OF THE INVENTION 
This invention relates to devices for pumps and processing devices for 
relatively delicate or easily damaged products. The invention may pump 
such products, to molds, casings, pouches, receptacles or other processing 
devices and is particularly suitable for use with whole muscle meat 
products and relatively delicate food products such as poultry parts, 
prepared food mixtures and the like. 
BACKGROUND OF THE INVENTION 
The processing and packaging of many goods, including foods, frequently 
requires dispensing relatively delicate or easily damaged products into 
molds, casings, other packaging or containers without overprocessing or 
unduly disturbing the composition and integrity of the product. This is 
particularly important in the processing of food products such as poultry 
parts, whole muscle or luncheon meat products, prepared foods containing 
cubed and diced or sliced meat, poultry, or fish and other formulations. 
Overprocessing of relatively delicate or easily damaged products by excess 
grinding, mixing or transferring, for example, will often significantly 
affect the composition and appearance of the products, and for food 
products, the flavor, texture and overall palatability of the products. At 
the same time, however, such products must often be quickly and 
efficiently transferred from a storage container or processing hopper to 
appropriate packaging in an economical and reliable manner. It is also 
frequently necessary to employ a single flexible system to continuously 
pump, process or package both small batch quantities for limited runs and 
large continuous volumes for commercial distribution. 
Devices used for such purposes often operate both at room temperatures and 
air pressures, at elevated or lowered temperatures, and in applications 
requiring vacuum (negative air pressure) conditions to deaerate the 
products prior to packaging. Deaeration of the products, particularly food 
products, improves the texture and appearance of the final packaged goods, 
appreciably increases the taste and shelf-life of the packaged goods and 
eliminates unwanted voids in the packaged goods. 
It is frequently desirable, in addition, to use piston pumps to dispense 
predetermined quantities of such relatively delicate or easily damaged 
products to the appropriate mold, casing, packaging or receptacle. These 
piston pumps must operate efficiently and at sufficient speeds to maintain 
economical processing operations. Moreover, the piston pumps must be 
durable, relatively simple to maintain, and easy to clean between 
processing operations to satisfy health and sanitary standards. 
SUMMARY OF THE INVENTION 
It is an object of the invention to provide an improved pumping device for 
relatively delicate or easily damaged products that is efficient, durable 
and easily maintained. 
It is a further object of the invention to provide an improved pumping 
device that dispenses relatively delicate or easily damaged products, such 
as whole muscle meats and fragile foods, continuously, efficiently and 
without degrading or overworking the products. 
It is another object of the invention to provide an improved food pumping 
device with an improved piston pump operable in conjunction with heating, 
cooling and vacuum deaeration systems. 
Further and additional objects will be apparent from the following 
description, drawings and claims. 
In one embodiment, for food products, the invention comprises a sealable 
hopper, preferably of stainless steel, for receiving a volume of the 
product. The hopper may be heated or cooled and is adaptable for both 
deaerating applications and for use in non-deaerating operations. The 
hopper may be provided with a hatch opening and a fill tube having a 
deaeration enhancing inlet valve to permit both batch and continuous 
processing of the product. 
The hopper is preferably shaped to gravity feed the product into at least 
one, and preferably two, synchronized piston pumps positioned proximate to 
the bottom of the hopper. The piston pumps displace the product from the 
interior of the hopper into a consolidating feed manifold where the 
product is then dispensed through a discharge conduit into suitable 
packaging materials, processing systems or other vessels or conduits. When 
the invention is used in conjunction with a vacuum system to deaerate the 
product, the piston pumps and consolidating feed manifold also prevent the 
loss of negative air pressure during the pumping operation. 
Each of the piston pumps preferably includes a pump cylinder enclosing a 
piston chamber or cavity. The pump cylinder preferably comprises a fixed, 
elongated, cylindrical sleeve housing and an elongated rotatable 
cylindrical sleeve positioned within the sleeve housing. Alternatively, 
the cylindrical sleeve housing may be rotatable around a fixed cylindrical 
sleeve positioned within the cylindrical sleeve housing as both of the 
cylindrical sleeves may be rotated. A first longitudinal opening or access 
port is formed in the fixed sleeve housing extending from the front to the 
rear of the housing. A corresponding second longitudinal opening or access 
port is formed in the rotatable sleeve. A hollow drive shaft keyed to a 
rotary actuator is connected to, and opens into, the rear wall of the 
rotatable sleeve. With this arrangement, the rotatable sleeve is 
reversably movable about the central axis of the piston chamber from a 
first, opened position to a second, closed position. 
In the opened position, the longitudinal opening in the rotatable sleeve is 
registered with the longitudinal opening in the fixed housing to permit 
product to pass from the hopper into the piston chamber. In the closed 
position, the opening in the rotatable sleeve is moved out of register 
with the opening in the housing to form a closed cylinder preventing the 
passage of product from the hopper into the piston chamber. 
One or more of the edges of at least the opening in the rotatable sleeve 
are preferably sharpened to cut and shear away any product that is only 
partially within the pump chamber when the rotatable sleeve is moved from 
an opened to a closed position. At least one of these longitudinal edges 
is disposed at an angle relative to the central axis of the piston chamber 
to exert a progressive, scissor-like cutting action on the product as the 
rotatable sleeve is closed. 
In the preferred embodiment, each pump is further provided with an ejection 
piston including a piston plate disposed within the piston chamber made of 
a tough, durable polymeric material. The piston plate is mounted on a 
piston rod extending through the hollow drive shaft of the rotatable 
sleeve to a hydraulic cylinder. When the piston is actuated by the 
hydraulic cylinder, the piston plate advances from the rear to the front 
of the piston chamber or cavity to positively expel product from the 
piston chamber through a consolidating feed manifold and into suitable 
receptacles, conduits or packaging. 
The piston plate is shaped to seal against the interior surfaces of the 
rotatable sleeve and the fixed sleeve housing. In the preferred 
embodiment, the piston plate is provided with a radially extending 
peripheral collar section that extends through the longitudinal opening in 
the rotatable sleeve. This collar section improves the sealing engagement 
between the piston plate and the interior surfaces of the sleeve housing. 
In the preferred embodiment, the piston pumps are disposed side by side 
near the bottom of the hopper to allow gravity feed of products into the 
pump chambers or cavities. The movement of the ejection pistons and 
rotatable sleeves of each pump are synchronized to provide a consistent 
and continuous flow of product to the consolidating manifold. The sleeves 
of each pump, in addition, preferably rotate in opposite directions 
towards the center of the hopper. This centrally disperses any small 
pieces of sheared product within the hopper to help ensure a consistent 
product composition and to prevent undesirable accumulation or clumping of 
small pieces within the device. 
In the preferred embodiment, the consolidating feed manifold comprises at 
least one, and preferably two, adjoining transmission passages in 
communication with the piston chambers or cavities. In the preferred 
embodiment, a transmission passage is in communication with each piston 
chamber. These transmission passages merge into a central convergence 
chamber sized to receive alternating surges of product from the piston 
pumps. The product exits the convergence chamber through a discharge 
conduit, preferably located opposite the transmission passages, to 
appropriate casings, molds, containers or the like. 
The central convergence chamber may be supplied with a movable diverting 
mechanism, preferably powered by rotary actuators, pneumatic cylinders, 
hydraulic cylinders or the like, that alternately seals the transmission 
passages during the pump cycles. As product is supplied to the convergence 
chamber through one of the transmission passages, the diverting mechanism 
is moved to engage the opening of the off-cycle transmission passage to 
prevent backflow of product. The diverting mechanism may also be adapted 
to prevent loss of negative air pressure from within the hopper when 
deaeration of the product is desired. 
The hopper, in addition, may be provided with a mechanical agitator to open 
and expose the product to a deaeration vacuum, to eliminate product voids 
and to enhance the deaerating operations of the device. This agitator 
preferably includes a first helical flighted section to agitate and move 
food product from the rear to the front of the hopper. The agitator also 
preferably includes a second section of hoop and paddle flighting to 
agitate the product and to urge the product into the piston pumps. The 
agitator is also preferably disposed proximate to the bottom of the hopper 
to aid the movement of product into the pumps and to evenly distribute 
product and pieces of product within the hopper. 
The invention, in addition, is not limited to the above recited embodiments 
or to use with the above mentioned food products. Rather, it includes 
further embodiments discussed and shown below in the drawings, description 
and claims, and their equivalents.

DETAILED DESCRIPTION OF THE INVENTION 
As shown in the Figures, and particularly FIGS. 1-3, one embodiment of the 
pumping device of the invention 10, adapted for use for food products, 
includes a housing 12 enclosing a hopper 14, or other holding vessel, 
channel system, tube system or the like, for holding and processing 
relatively delicate products, an optional agitator 16, operatively 
disposed within the hopper 14, and dual pump cylinders 18 and 20 disposed 
to receive product from the hopper 14. A consolidating feed manifold 22 is 
operatively connected to the housing 12 in communication with the piston 
pump cylinders 18 and 20. The housing 12 may also be provided with a 
deaeration enhancing inlet valve ("DEIV") 24 used in conjunction with a 
product fill tube (not shown) for the continuous supply of product to the 
hopper 14, for use when the device 10 is operating in a deaerating 
configuration. 
As shown in FIGS. 1-3, the housing 12 comprises side panels 30 and 32, a 
front panel 34 and rear panel 36. The hopper 14 may be open or may be 
provided with a sealable top hatch 40 to complete the housing 12. In the 
preferred embodiment, the device 10, including the housing, is primarily 
made of No. 300 series stainless steel or other U.S.D.A. approved tough, 
durable and easily cleaned materials. When used, the top hatch 40 is 
joined to the housing 12 by an articulated locking hinge 42 and may be 
provided with viewing ports (not shown). In the embodiment shown in FIGS. 
1-3, pneumatic or hydraulic cylinders 44 extend between the hatch 40 and 
the front and rear panels 34 and 36 to permit the selective movement of 
the hatch 40 between an opened and closed position. 
The housing front panel 34 includes front pump access ports 50 and front 
agitator mounting assembly 52 proximate to the agitator mounting opening 
54. Similarly, the housing rear panel 36 includes rear pump access ports 
56, rear agitator access opening 58 and rear agitator mounting assembly 
and gear box 60. 
As shown in FIGS. 1-3, the hopper 14 comprises a pair of opposed side walls 
70 and 72, and front wall 74 and rear wall 76 formed by the interior 
surfaces of the housing front panel 34 and rear panel 36. End angles 
provided with a flexible rubber gasket or similar such material may be 
attached to the upper edges of the hopper walls 70 and 72, and front wall 
74 and rear wall 76 to engage the top hatch 40 and to seal the hopper 14 
from the outer atmosphere. This permits the operation of the device in 
configurations employing vacuum (negative air pressure) systems to 
deaerate product held in the hopper 14. 
As shown in FIGS. 2 and 4, the hopper side walls 70 and 72 are preferably 
made of stainless steel or other such U.S.D.A. acceptable, tough, durable 
and easily cleaned materials. The hopper side walls 70 and 72 are inclined 
toward the bottom of the device 10 to promote the downward, gravity feed 
movement of product within the hopper 14. As shown in FIG. 4, the rearward 
portions 70a and 72a of the side walls 70 and 72 extend downwardly to a 
curved bottom 80 of the hopper 14. The curved bottom 80 is also positioned 
to encourage the movement of product toward the piston pumps 18 and 20. 
The forward portions 70b and 72b of the hopper side walls 70 and 72 extend 
downwardly to cylindrical sleeve housings 90 and 92 of the piston pumps 18 
and 20. 
In the preferred embodiment, the hopper side walls 70 and 72 include first 
vertical upper wall sections 70c and 72c. Second hopper wall sections 70d 
and 72d extend inwardly from the lower boundary of the upper sections, 70c 
and 72c, to third lower hopper wall sections 70e and 72e. The third 
sections 70e and 72e extend inwardly at an angle to the curved bottom 80 
of the hopper 14 and the sleeve housings 90 and 92. 
As shown in FIGS. 1 and 2, the hopper 14 is preferably reinforced with 
stainless steel or similar durable, U.S.D.A. acceptable, side wall brace 
channels 94 and 96 spanning the junction of the second and third wall 
sections 70d, 70e and 72d, 72e. These brace channels 94 and 96 extend the 
full length of the hopper side walls 70 and 72. 
As shown in FIGS. 2-4, the hopper bottom 80 spans the distance from the 
housing rear panel 36 to a transition plate 98 disposed intermediate the 
housing front panel 34 and rear panel 36. In the preferred embodiment, the 
transition plate is also of stainless steel and the periphery 98a of the 
plate may extend beyond outer edges of the curved hopper bottom 80. 
As shown in FIGS. 2 and 4, the transition plate 98 forms a vertical 
"step-down" to a U-shaped support channel 100. The support channel 100 
extends from the housing front panel 34 to the housing rear panel 36. 
In the preferred embodiment, as shown in FIGS. 1-3, the interior of the 
hopper 14, is collectively defined by the side walls 70 and 72, front wall 
74, rear wall 76, curved bottom wall 80, sleeve housings 90 and 92, and 
transition plate 98. When used in conjunction with the top hatch 40, the 
hopper 14 may be adapted to comprise a vacuum chamber for receiving 
products for pumping and/or processing. The products may be pumped in 
batches supplied to the hopper 14 through an opened top hatch 40, an 
opened hopper 14, or continuously by vacuum feed or other means from a 
remote hopper or vat (not shown) using a fill tube in conjunction with the 
DEIV 24. 
The top hatch 40 may be provided with a vacuum-fitting to permit coupling 
to a source of negative pressure so that the hopper 14 may be evacuated of 
air during deaeration operations. Alternatively, a self-contained negative 
pressure source (not shown) may be operatively disposed within the housing 
12 and connected to a vacuum fitting or another such fitting in 
communication with the hopper 14. The hatch may also be provided with a 
vacuum gauge 102 to monitor conditions within the hopper. 
The hopper 14, in addition, may be of other dimensions and may be equipped 
with heating elements (not shown) to process the food products at elevated 
temperatures, including resistance elements, steam fittings, jackets or 
other heating means known to the art. Similarly, the hopper may be 
equipped with cooling means (not shown) to process food products at 
lowered temperatures, including refrigerant coils, nitrogen ports, nozzles 
or other such cooling apparatus known to the art. 
As shown in FIGS. 3 and 10, the agitator 16 comprises an elongated shaft 
110 mounted and supported by the front agitator mounting assembly 52 and 
rear agitator mounting assembly and gear box 60, both with suitable 
mounting brackets and rotatable bearing elements. In the preferred 
embodiment, the agitator 110 shaft supports a section of ribbon flighting 
112 arranged in a generally helical pattern to promote the agitation of 
the product within the hopper 14 and the movement of the product from the 
rear of the hopper 14 towards the pump cylinders 18 and 20. As shown in 
FIGS. 3 and 10, the agitator shaft 110 also preferably supports hoop 
members 114 and paddle members 116. These members 114 and 116, with the 
helical flighting 112, agitate and open voids in the product and urge the 
product into the pumps 18 and 20, as well as encourage the even 
distribution of the product and portions of the product within the hopper 
14. One or more of the hoop support members 114a may also be positioned to 
scrape and wipe product from the face of the hopper front wall 74. 
The agitator 16 is preferably equipped to operate at various speeds 
depending on the application and type of product being processed. In many 
instances, the agitator 16 will rotate relatively slowly to ensure proper 
mixing and deaeration without undue injury or overworking of relatively 
delicate products. A drive means (not shown) is operatively coupled to the 
rear agitator mounting assembly and gear box 60 to rotate the agitator 16. 
In the preferred embodiment, the drive means is mounted on the device 10 or 
proximate to the device and may consist of a variable-speed, hydraulic or 
pneumatic drive, a gear system, a chain and sprocket transmission or 
similar such systems. Alternatively, the drive motor may be a remote power 
source and may use other transmission systems known to those in the art. 
Similarly, the drive motor and transmission system is preferably equipped 
to operate at a variety of speeds depending on the expected use of the 
device 10. 
As shown in FIGS. 2 and 3, the agitator 16 may be spaced generally below 
the DEIV 24, in close proximity to the curved hopper bottom wall 80 and 
the piston pumps 18 and 20. In configurations using an agitator 16, the 
level of the product within the hopper 14 starts just below the top of the 
helical flighting 112 and hoop member 114. A level of product between the 
top and bottom of the flighting 112 is maintained in continuous operations 
until completion of the processing procedure. The device 10 in automated 
operations may also be provided with automatic high-low product level 
controls such as those known in the art to monitor and to control the 
automatic feed of product into the hopper 14. 
As shown in FIGS. 3-8 the cylindrical sleeve housings 90 and 92 comprise 
one component of the dual pump cylinders 18 and 20. The sleeve housings 90 
and 92 are preferably of stainless steel or another tough, durable, 
non-galling, U.S.D.A. acceptable, and easily cleanable material. They are 
preferably welded to the transition plate 98 and to the hopper front wall 
74 proximate to the front pump access ports 50. 
As shown in FIGS. 4 and 6, the sleeve housings 90 and 92 include open 
forward portions 90a and 92a adjacent to the front pump access ports 50 
and, as shown in FIG. 5, rear walls 90b and 92b formed by the interior 
surface of the transition plate 98. The peripheral wall edges 120 and 122 
are formed along sleeve housing openings 124 and 126. These openings 120 
and 122 permit movement of product from the hopper 14 into the piston 
chambers or cavities 128 and 130. In the preferred embodiment, the 
openings 124 and 126 extend for approximately 140 degrees of the 
circumference of each sleeve housing 90 and 92 and may be sharpened to a 
cutting edge. 
The sleeve housings 90 and 92, in addition, may be provided with 
circumferential reinforcing bands 132 and 134 disposed intermediate of the 
forward portions 90a and 92a and rear walls 90b and 92b of the sleeve 
housings. These reinforcing bands 132 and 134 strengthen the sleeve 
housings 90 and 92 and prevent spreading or other deformation of the 
housings 90 and 92 during operation of the invention. In the preferred 
embodiment, each reinforcing band 132 and 134 is located at approximately 
the midpoint of its respective sleeve housing. 
As shown in FIGS. 2, 5 and 7-8, the sleeve housings 90 and 92 are attached 
to the transition plate 98, in a side-by-side parallel relation. The 
sleeve housings 90 and 92 are also disposed a vertical distance from the 
curved hopper bottom 80 to ensure the optimum movement of product from the 
hopper 14 into the piston pumps 18 and 20. In the preferred embodiment, 
the sleeve housings 90 and 92 are positioned on the transition plate 98 so 
that the uppermost circumferential arc of the sleeve housing openings 124 
and 126 are somewhat below the forward edge of the curved hopper bottom 
80. 
An inverted V-shaped product guide 138 is placed above the two sleeve 
housings 90 and 92, straddling the space between the pair of adjacent 
sleeve housing edges 120 and 122 to guide food product into the pumps 18 
and 20. The product guide 138 preferably extends the length of the 
housings 90 and 92 and is composed of U.S.D.A. approved stainless steel or 
another such material. One of the V-legs of the product guide 138 is 
attached to, or is proximate to, the adjacent sleeve housing peripheral 
edges 120 and 122. 
As shown in FIGS. 3-8, the pump cylinders 18 and 20 are further provided 
with cylindrical rotatable sleeves 140 and 142 nested within the sleeve 
housings 90 and 92 to enclose the piston chambers 128 and 130. The 
rotatable sleeves 140 and 142 each comprise an outer wall section with 
longitudinal peripheral edges 146 and 148 formed along openings 150 and 
152 in the sleeve wall. In the preferred embodiment, the opening in each 
sleeve wall 150 and 152 extends for approximately 140 degrees of the 
circumference of the sleeves 140 and 142. 
The rotatable sleeves 140 and 142 are further provided with open forward 
ends 140a and 142a and rear end walls 140b and 142b. As shown in FIGS. 4 
and 6, the sleeve forward ends 140a and 142a extend a distance past the 
sleeve housing open forward portions 90a and 92a and through the front 
pump access ports 50. As shown in FIGS. 3 and 5, hollow piston shafts 154 
and 156 extend centrally and laterally from the exterior of the sleeve 
rear end walls 140b and 142b Each piston shaft 154 and 156 is provided 
with an axial bore 158 and 160, opening into the piston chambers 128 and 
130 respectively. Protruding key flanges 162 and 164 are formed on the 
exterior of the hollow piston shafts 154 and 156, and extend along at 
least a portion of the length of the shafts 154 and 156. 
As shown in FIGS. 4 and 7-9, one or both of the longitudinal peripheral 
edges 146 and 148 of the preferred rotatable sleeves 140 and 142 may be 
machined to form knives or knife-like leading edges for slicing away any 
product that extends partially into the piston chambers 128 and 130. As 
shown in FIGS. 5 and 7-9, the peripheral edges 146 and 148 may also be 
angularly disposed relative to the longitudinal axis of the piston 
chambers 128 and 130. They are preferably at an angle of approximately 10 
degrees and extend substantially from the sleeve forward ends 140a and 
142a to a point near the sleeve rear walls 140b and 142b. 
The peripheral edges 146 and 148 cooperate with the sleeve housing edges 
120 and 122 to provide a progressive scissor-like slicing action when the 
sleeves 140 and 142 are rotated. This scissor-like action efficiently 
separates portions of excess product from product within the pump 
cylinders 18 and 20, and urges the portions or partial product portions to 
a central area in the hopper for redistribution within the hopper. This 
also helps to produce relatively uniform and consistent product output. 
As shown in FIGS. 4 and 5, when the rotatable sleeves 140 and 142 are in 
place within the sleeve housings 90 and 92, the piston shafts 154 and 156 
of rotatable sleeves 140 and 142 extend through shaft openings 168 and 170 
in the transition plate 98. Bearing support plates 172 and 174 are 
interposed between the sleeve rear walls 140b and 142b and the sleeve 
housing rear walls 90b and 92b to facilitate the rotational movement of 
the sleeves 140 and 142 and to protect the sleeves 140 and 142 and sleeve 
housings 90 and 92 from excessive wear. 
The bearing support plates 172 and 174 are made of ultra-high molecular 
weight polyethylene and may be provided with resilient seal members, such 
as rubber quad rings or other similar materials, to engage exteriors of 
the rotatable sleeve rear walls 90b and 92b and prevent leakage of product 
out of the pump cylinders 18 or 20 or air into the hopper during 
deaeration procedures. Similarly, the peripheral edges of the rotatable 
sleeve open forward ends 140a and 142a, shown in FIGS. 4 and 6, may be 
provided with resilient sealing members to seal against the inner surfaces 
of the sleeve housings 90 and 92. 
As shown in FIGS. 3 and 5, the hollow piston shafts 154 and 156 preferably 
extend through the central cores of rotary actuators 194 and 196. Such 
rotary actuators are commonly known in the art and the preferred actuator 
includes those known by the trade name Hyd-ro-ac sold by Textron, Berne, 
Ind. The rotary actuators 194 and 196 are powered by hydraulic systems 
(not shown) and are attached to mounting plate 200 positioned a 
predetermined distance from the transition plate 98. Other actuators, 
including those using various geared, belted, pneumatic, rack and pinion 
or other such designs, may also be used. 
As shown in FIG. 5, the key flanges 162 and 164 protruding from piston 
shafts 154 and 156 are adapted to positively engage corresponding keyways 
formed in the central bores of the rotary actuators 194 and 196. Thus, 
when the rotary actuators 194 and 196 are energized, they axially rotate 
the sleeve 140 and 142 in either a clockwise or counterclockwise 
direction. 
As shown in FIGS. 4, 5, 7 and 8, the piston shafts 154 and 156 and the 
rotary actuators 194 and 196 are oriented so that the sleeves 140 and 142 
alternately rotate from a first open position I to a second closed 
position II. In the preferred embodiment, as shown in FIGS. 7 and 8, the 
sleeve 140 and 142 are turned in opposing directions so that both sleeves 
140 and 142 are rotated towards the center of the hopper 14. 
When the rotatable sleeves 140 and 142 are in the first open position I 
(FIG. 7) their peripheral edges 146 and 148 are positioned in register 
with the peripheral edges 120 and 122 of the sleeve housings 90 and 92. In 
this position, the piston chambers 128 and 130 are open to the hopper 14 
to permit movement of product into the chambers. 
As the sleeves 140 and 142 are alternately rotated to their second closed 
position II (FIG. 8) their longitudinal peripheral edges 146 and 148 are 
moved out of register with the peripheral edges 120 and 122 of the sleeve 
housings 90 and 92. This rotation continues until the outer walls of the 
rotatable sleeves 140 and 142 completely close-off the sleeve housing 
openings 150 and 152 and form a closed cylinder so that product can be 
discharged through the sleeve openings 140a and 142a. 
As shown in FIGS. 3, 5 and 12, the pump cylinders 18 and 20 are further 
preferably provided with pump cylinder position detectors 210 and 212 
disposed between the transition hopper plate 98 and the rotary actuators 
194 and 196 to control the angular position of the rotatable sleeves 140 
and 142. Each of the two pump cylinder position detectors 210 and 212 
preferably includes first U-shaped induction sensors 214 and second 
U-shaped induction sensors 216 attached by brackets 218 to the transition 
plate 98. Induction sensors are well known to the art and the preferred 
sensors include those sold under the trade name Turck Inductive Sensor, by 
Turck Multiprox, Inc., Minneapolis, Minn. Other mechanical and 
electro-mechanical, and electrical devices such as various switches, stop 
members and the like may also be used as alternatives to the induction 
sensors. 
As shown in FIGS. 5 and 12, each set of the pump cylinder induction sensors 
214 and 216 are disposed to receive the lobe portions 220a and 222a of 
actuating cams 220 and 222 within the U-legs of the sensors. The cams 220 
and 222 are secured to the rotary actuators 194 and 196 and are positioned 
between the rotary actuators 194 and 196 and the transition plate 98. The 
first pump cylinder induction sensors 214 are arranged to detect the lobe 
position of the cams 220 or 222 when the rotating sleeves 140 and 142 are 
in their open position I discussed above. The second pump cylinder 
induction sensors 216 are positioned to detect the location of the cams 
220 or 222 when the sleeves 140 and 142 are in the closed position II. 
Both sets of pump cylinder sensors 214 and 216 signal the rotary actuators 
194 and 196 to cease further rotation when the sleeves are either fully 
open or fully closed. The pump cylinder position detectors 210 and 212 are 
further sequenced to permit alternating, synchronized rotation of the 
sleeves 140 and 142, so that as one sleeve moves to a closed position, the 
other sleeve is rotated to an open position. 
As shown in FIGS. 3-9, the pumps 18 and 20 are further provided with 
cylinder pistons 230 and 232 comprising piston rods 234 and 236, and 
piston plunger plates 238 and 240 mounted to the piston rods 234 and 236. 
The piston plunger plates 238 and 240 are preferably generally disk-shaped 
plates of ultra-high molecular weight polyethylene or similar non-ferrous, 
non-binding, self-lubricating materials or combination of such materials. 
Central openings are formed in the plunger plates 238 and 240 for 
receiving the forward end of the piston rods 234 and 236. These openings 
are sized to allow the plunger plates 238 and 240 to freely rotate on the 
piston rods 234 and 236. 
As shown in FIGS. 4, 7-9 and 11, the diameters of the piston plunger plates 
238 and 240 are preferably sized to provide sealing engagement between the 
periphery of the plunger plates 238 and 240, the sleeve housings 90 and 92 
and the rotatable sleeves 140 and 142. In the preferred embodiment, the 
plunger plates 238 and 240 are additionally provided with radially 
outwardly extending peripheral collar sections 246 and 248 to enhance the 
seal against the interior surfaces of the sleeve housings 90 and 92. 
These collar sections 246 and 248 extend between the rotatable sleeve 
longitudinal peripheral edges 146 and 148 to engage the inner surface of 
the sleeve housings 90 and 92. The edges of the collar sections 246 and 
248 are recessed slightly from the rotatable sleeve longitudinal edges 146 
and 148 to prevent binding or rubbing between the plunger plates 238 and 
240 and the longitudinal peripheral edges 146 and 148 during operation of 
the pumps. In the preferred embodiment, the collar sections 246 and 248 
measure approximately 138 degrees of the circumference of the plunger 
plates 238 and 240. 
As shown in FIGS. 4, 5 and 7-9, when installed on the piston rods 234 and 
236, the plunger plates 238 and 240 are retained in position with 
retaining plate sleeves 250 and 252 and fixed back stop washer members 
250a and 252a disposed behind the plunger plates 238 and 240. The forward 
ends of the piston rods 234 and 236 are reduced in diameter and threaded 
to receive the correspondingly threaded retaining plate sleeves 250 and 
252. These forward ends of the piston rods 234 and 236 extend through the 
plunger plates 238 and 240. The retaining plate sleeves 250 and 252 are 
threaded onto the piston rods 234 and 236 and are tightened to press the 
back stop washers 250a and 252a. The retaining plate sleeves 250 and 252 
are preferably configured so that spare from the back stop washers 250a 
and 252a is allowed to permit the free rotation of the plunger plates 238 
and 240. 
As shown in FIG. 5, the piston rods 234 and 236 extend through ports and in 
the rotatable sleeve rear end walls 140b and 142b, into the piston shaft 
bores 158 and 160, through the entire length of the piston shafts 154 and 
156 to hydraulic cylinders 270 and 272. The piston rods 234 and 236 are 
operatively coupled to the hydraulic cylinders 230 and 232 to provide 
reversible lateral piston stroke movement during operation of the pumps. 
The hydraulic cylinders 270 and 272 used in the invention are well known 
to the art, and, in the preferred embodiment, include high pressure 
hydraulic cylinders such as those sold under the trade name "T-J.TM. 
Cylinders" by the Aeroquip Company. Other types of piston drives, such as 
pneumatic, electrical and similar drives may also be used. 
The hydraulic cylinders 270 and 272 are bolted to the cylinder mounting 
plate 274. Hex head machine screws secure the cylinder mounting plate 274 
to the mounting plate 200. The cylinder mounting plate 274 is further 
spaced from the mounting plate 274 by cylinder standoffs 276. The 
hydraulic cylinders 270 and 272 are powered by a separate hydraulic power 
source (not shown) that may be included within the housing 12 or at a 
remote location. The cylinders 270 and 272 also extend through rear panel 
access ports 56. 
As shown in FIGS. 1, 3 and 6, the consolidating manifold 22 is secured to 
the manifold mounting plate 292, which is attached with hinge 294 to the 
exterior of the housing front panel 34. The hinge 294 is fixed to both the 
mounting plate 292 and the housing front panel 34 by hinge bolts and 
standoffs 296. The mounting plate 292 is secured in operative alignment 
with the pump cylinders 18 and 20 by knurled knobs (not shown) spaced 
along the borders of the mounting plate 292. 
A transition plate 300 of ultra-high molecular weight polyethylene or 
similar materials, as mentioned above, with a sealing member (rubber quad 
ring or the like) is interposed between the mounting plate 292 and the 
housing front panel 34 opposite the pump access ports 52. The transition 
plate 300 is provided with openings corresponding to the pump access ports 
52 allowing communication between the pump cylinders 18 and 20 and the 
transmission passages 308 and 310 of the consolidating discharge manifold 
22. The transition plate 300 prevents leakage of product during operation 
of the pump cylinders 18 and 20 and accidental loss of negative air 
pressure when the device is operating in a deaerating configuration, as 
well as bearing support to the forward ends 140a and 142a of the rotatable 
sleeves. 
As shown in FIGS. 1, 3, 6 and 13, the transmission passages 308 and 310 are 
preferably disposed in a parallel adjoining relation. Each transmission 
passage 308 and 310 comprises a first tapering conduit segment 320 and a 
second cylindrical duct segment 322. The open end of each duct segment 322 
extends a short distance through the side wall of a central, cylindrical 
convergence chamber 324 sized to receive alternating surges of product 
from the pump cylinders 18 and 20 through the transmission passages 308 
and 310. 
The cover 326 of the convergence chamber 324 is preferably removable for 
cleaning and inspection of the chamber 324. The cover 326 may be secured 
to the convergence chamber 324 with knurled knobs (not shown) and may be 
provided with a seal ring to prevent leakage from the convergence chamber 
324. 
As shown in FIGS. 1, 3, 6 and 13, 17 and 18, the central convergence 
chamber 324 also may be supplied with pivoting or rotating diverting gates 
disposed to alternatingly close the open ends of each transmission passage 
308 and 310 within the chamber 324. The preferred embodiment of the 
diverting gate is the crescent configuration shown in FIGS. 1, 17 and 18. 
This embodiment is suitable for products such as whole muscle meats, as 
well as for particulate or emulsified products. The diverting gate may 
also be of a planer configuration, as shown in FIGS. 3, 6 and 13, which is 
suitable for certain types of products, such as particulate or emulsified 
foods and similar materials. Other configurations suitable for closing the 
transmission passages 308 and 310 may also be used. 
The diverting gates prevent the backflow of food product from one 
transmission passage to the other during the pump cycles and help to 
maintain negative air pressure within the hopper 14 when the device is 
operating in a deaerating configuration. When correctly synchronized with 
pumps 18 and 20, the gates may also help to prevent or eliminate voids 
within the continuous product discharge during the pump cycles. The 
movement of the gates may also be timed so that the product in the pumps 
18 and 20 and in the passages 308 and 310, may be initially precompressed 
by the pumps 18 and 20 to eliminate voids or pockets in the product before 
the pumps 18 and 20 advance the product through the consolidating feed 
manifold 22. 
The embodiment of the consolidating feed manifold 22 shown in FIGS. 3, 6 
and 13 is provided with a planar diverting gate 330. The planar gate 330 
rotates on a gate pivot pin 331 attached to, or embedded in the gate 330. 
The pivot pin 331 extends through the bottom wall 332 of the central 
convergence chamber 324 and through a flanged pillow block 333. The planar 
diverting gate 330 is actuated by pneumatic cylinder 334 pivotally linked 
to the gate pin 331 through cylinder rod clevis and crank arm 335. 
In the embodiment shown in the FIGS. 3, 6 and 13, the pneumatic cylinder 
334 for the planar gate 330 is rotatably fixed to a cylinder clevis 336 
mounted on cylinder standoff with clevis bracket 337. The planar gate 330 
may also be provided with cutting edges or similar means to cut or shear 
product remaining in either transmission passage 308 or 310, or may be 
modified in configuration for the same purpose. 
As shown in FIGS. 1, 17 and 18, the preferred embodiment of the diverting 
gate is the crescent gate 340 which also pivots within the convergence 
chamber 324 to alternately close the transmission chambers 308 and 310. 
The crescent gate 340 comprises a first, horizontally disposed triangular 
upper arm 341; a second horizontally disposed triangular lower arm 342, 
spaced from the first arm 341; and a curved gate wall 343 connecting the 
peripheral, radial edges of the upper arm 341 and lower arm 342. 
In this embodiment, the inner surface of the cover 326 of the convergence 
chamber 324 is provided with a subtending boss 344. A sleeve bearing of 
ultra high molecular weight polyethylene or other suitable materials is 
mounted on the boss 344. An opening 345 is formed with the upper arm 341 
of the crescent gate 340 for receiving the boss 344 to form an upper pivot 
for the crescent gate 340. 
A corresponding opening 346 is formed in the lower arm 342 of the crescent 
gate 340, opposite the upper pivot point, to receive a splined shaft 347 
of a gate rotary actuator 348 extending through the bottom wall 332 of the 
convergence chamber 324. As shown in FIG. 18, the opening 346 of the lower 
arm is provided with teeth to engage the splined shaft 347 and to ensure 
efficient transfer of the rotational drive from the gate rotary actuator 
348 to the crescent gate 340. An O-ring 349 of ultra high molecular weight 
polyethylene or similar materials, is interposed as a bearing member 
between the lower arm 342 and the bottom 332 of the convergence chamber 
324. This O-ring 349 facilitates the movement of the crescent gate 340, 
and seals the convergence chamber 324 from leaks or seepage. 
The curved gate wall 343 is configured to correspond to the curvature and 
dimension of the side wall of the convergence chamber 324. The curved gate 
wall 343 is also configured to ensure that the gate wall 343 blocks and 
closes one of the two transmission passages 308 or 310 when the gate wall 
343 is positioned at the opening of those passages. The exposed peripheral 
edges 343a of the curved gate wall 343 are preferably sharpened to 
knife-like edges to shear away any product or portions of product 
extending from the transmission passages 308 and 310 partially into the 
convergence chamber 324. 
An additional gate bearing plate 350 may also be employed to further ensure 
a proper seal between the curved gate wall 343 and the transmission 
passages 308 and 310. This gate bearing plate 350 preferably extends a 
sufficient distance around the circumference of the convergence chamber 
324 to surround the openings of the transmission passages 308 and 310, and 
extends a distance beyond both of those openings. The convergence chamber 
324 may also be provided with pins 350a positioned on either side of the 
bearing plate 350. These pins 350a stop excess rotation of the crescent 
gate 340 within the convergence chambers 324. 
As shown in FIGS. 17 and 18, the rotary actuator 348 is mounted to the 
exterior of the convergence chamber bottom wall 332 by a mounting block 
351 affixed to the bottom wall 332 and an intermediate mounting plate 352. 
Attached to the opposite end of the rotary actuatory 348 is a position 
sensor mounting plate 353. Attached to this plate 353 by brackets 354 are 
gate position sensors 355 and 356. These sensors, like those of the pump 
cylinders mentioned above 214 and 216, are preferably U-shaped induction 
sensors adapted to receive the lobe portion 357a of actuating cam 357. 
This cam 357 is preferably mounted to the distal end of the rotary 
actuator shaft 347. 
These gate position detectors 355 and 356 operate essentially in the same 
manner as the pump cylinder position detectors 216 and 216 discussed 
above. They control both the position and the movement of the gate rotary 
actuator to help ensure consistent and automated operation of the device. 
The rotary actuator assembly is also enclosed within a drive cover 358, 
bolted to the convergence chamber bottom. This cover 358 is preferably 
provided with ports for the electrical and hydraulic lines (not shown) 
used to operate the rotary actuators 348 and position detectors 355 and 
356. 
As mentioned above, gates with other configuration and movement paths may 
also be used. Other gate actuator systems, such as hydraulic, rotary 
actuated or electromechanical drives may be used as well. 
The product exits the convergence chamber 324 through discharge conduit 359 
extending through the side wall of the convergence chamber 324. In the 
preferred embodiment, the discharge conduit 359 is located opposite the 
transmission passages 308 and 310, although it may be also disposed in 
other locations. The preferred discharge conduit 359 is also provided with 
sanitary ferrule 359a for engagement with downstream equipment. 
As mentioned above, in one embodiment for a deaeration configuration, the 
device 10 may be provided with an optional deaeration enhancing inlet 
valve 24 ("DEIV") incorporated into a product supply passage as shown in 
FIGS. 2, 3 and 14. As shown in FIG. 14, the DEIV includes an elbow inlet 
conduit 360 extending through a port 362 in the hopper side wall 70 into 
the interior of the hopper 14. The port 362 is located at the upper level 
of the product contained within the hopper 14 when the device is in 
operation. 
The exterior exposed end portion 364 of the elbow inlet conduit 360 is 
preferably attached to a sanitary ferrule 366 and furnished with a tube 
gasket 368 and short-weld ferrule 370 by clamp 372, for engagement with 
other processing equipment. The inlet conduit 360 is attached to the 
hopper side wall 70 positioning the elbow bend of the conduit 360 parallel 
to the hopper bottom 80, with the open end 374 of the conduit 360 within 
the hopper 14 directed toward the housing rear panel 36. 
Poppet valve assembly 380 is positioned opposite the interior opening 374 
of the conduit 360. The valve assembly 380 is provided with a disseminator 
poppet 382 mounted on poppet plate 384, with a poppet gasket 386 disposed 
between the poppet 382 and poppet plate 384. The poppet plate 384 is 
attached or threaded to reversably traveling poppet stem 388 extending 
through the poppet valve port 390 in the housing rear panel 36. The poppet 
stem 388 also passes through stem seal 392, with a sealing member (such as 
a rubber quad ring) and O-ring secured to the rear panel 36 by stem seal 
mounting plate 398 and knob nuts 400. 
The exposed end of the poppet stem 388 is pivotally linked to the rod 
clevis 402 of pneumatic air cylinder 404, or other such drive means as 
mentioned above, mounted on standoff 406 by hex bolts 408. The pneumatic 
air cylinder 404 may be powered by sources internal to the device or by 
remote sources of pneumatic force. 
In operation, the DEIV 24 acts to distribute and open pockets in product 
drawn or pumped into the hopper 14 by the vacuum within the hopper or by 
other means. The product passes through the inlet conduit 360 to contact 
the tapered poppet 382. On impact, the product is fragmented into smaller 
portions to expose the maximum surface area to the vacuum within the 
chamber for removing any trapped pockets within the product and then falls 
into the hopper. The poppet 382 may be selectively positioned relative to 
the open end 374 of the inlet conduit 360 by the pneumatic cylinder 404 to 
maximize the benefits of the DEIV valve 24. 
As shown in FIGS. 1-3, the device housing 12 is further preferably mounted 
on wheeled members 410, including casters 412, to permit the convenient 
movement of the device 10 from place to place. The preferred embodiment, 
also may include an internal hydraulic fluid reservoir and hydraulic 
motor(s) (not shown) for use in connection with the above-mentioned 
hydraulic actuators 194 and 196 and hydraulic cylinders 230 and 232, and 
the agitator 16, mounted below the hopper 14 proximate and parallel to one 
of the housing side panels 30 or panel 32. 
In operation, the product is either batch loaded into the device 10 through 
an open hatch 40, a hatchless embodiment for non-vacuum applications, or 
continuously pumped or drawn into the device through the sanitary inlet 
tube incorporating the DEIV 24 to a preferred level within the hopper 14. 
When an agitator 16 is used, particularly in deaerating applications, the 
product level is often allowed to fluctuate between the top of the 
agitator ribbon flighting 112 at the agitator shaft 110. The product is 
then slowly and gently stirred by the agitator 16, when an agitator 16 is 
utilized, to reduce air pockets, product clumps and to mix any additives 
or dissimilar materials into the product and to assist in breaking up the 
product to expose more surfaces to the deaerating vacuum in deaeration 
operations. 
For deaerating configurations, and other configurations when necessary, 
sensing systems known to the art may be used to determine the amount of 
product supplied to the device 10, the product level and, in the 
deaerating applications, the negative pressure within the hopper 14. These 
sensing systems may be combined with control systems also known to the art 
to maintain the above conditions at the optimum levels. 
The product may be agitated for a period of time for mixing, cooling, 
heating or other processing purposes. Alternatively, the pumping procedure 
may be initiated immediately. During the pumping procedure, the flighting 
and hoop members 112 and 114 of the agitator 16 generally direct the 
product towards the pump cylinders 18 and 20 where the product is urged by 
gravity flow and the movement of the agitator 16 into the piston chambers 
128 and 130. 
In normal operation, the rotatable inner sleeve 140 of the first pump 
cylinder 18 of the two synchronized pumps is disposed in an open position 
I with the inner sleeve longitudinal edges 146 in register with the 
longitudinal edges 120 of the sleeve housing 90 to permit product to pass 
into the piston chamber 128. At the same time, the second pump cylinder 20 
is in a closed position II, with the second inner sleeve longitudinal 
edges 148 out of register with the longitudinal edges 122 of the second 
sleeve housing 92 so that the outer wall of the sleeve 142 prevents the 
movement of product into the piston chamber 130. 
While the first piston chamber 128 is filling with food product, assisted 
by the agitator assembly 16, in one embodiment, the piston 230 of the 
first pump cylinder 18 is in a fully retracted position with the first 
piston plunger plate 238 proximate to the sleeve rear wall 140b and 
housing rear wall 90b. A predetermined period of time is allowed to ensure 
that the open piston chamber 128 is filled with product. Alternatively, it 
may be advisable in certain applications to employ sensors, such as those 
known in the art, to monitor the contents of the pump chamber 128 and to 
start the rotary actuator 194 when the product reaches a predetermined 
level within the pump chamber 128. 
When piston chamber 128 is filled, the rotary actuator 194 is activated to 
move the first rotatable sleeve 140 from its open in-register position I, 
to its closed out-of-register position II sealing the first piston chamber 
128 from the interior of the hopper 14. When the first sleeve 140 is 
rotated, the sharpened sleeve edges 146 cooperate with the first sleeve 
housing edges 120 to shear away any product or pieces of product that are 
not completely within the pump chamber 128. As the sleeve edges 146 are 
angularly disposed relative to the longitudinal axis of the pump, this 
shearing action is gradually and progressively applied across the length 
of sleeve 140. Any sheared segments or pieces of product are redistributed 
by the agitator 16, if utilized, within the hopper to prevent an 
undesirable buildup in one location of such segments resulting in 
inconsistent finished product. 
When the position detectors 210 sense that the first sleeve 140 is 
completely rotated to its closed position II, the hydraulic piston 
cylinder 270 is activated and the piston 230 is axially extended through 
the piston chamber 128. The piston plunger plate 238 forces the product 
out of the chamber 128 through the port 50 and into the first transmission 
passage 308 of the consolidating discharge manifold 22. Once the piston 
230 reaches its full stroke, it is retracted to its original position and 
the rotary actuator 194 is activated to return the first sleeve 140 to its 
open position I. 
To ensure a consistent synchronized pump action, the second pump cylinder 
20 is activated once the position detector 210 senses that the first pump 
cylinder 18 is at, or approaching, the above-mentioned closed position II. 
At that time, the second rotatable sleeve 142 of the second pump cylinder 
20 is moved from its closed position II to an open position I for 
receiving product within the pump chamber 130. The product advances into 
the second pump chamber 130 and the second pump cylinder 20 follows the 
same cycle, as described above, for the first pump cylinder 18. 
The cycling of the two pump cylinders 18 and 20 are synchronized so that as 
one pump is closing and beginning to expel product from its piston 
chamber, the other pump is filling and preparing for the expulsion step. 
This provides a constant and steady supply of product to the consolidating 
manifold 22. 
Once the product enters the consolidating manifold 22, it passes through 
transmission passages 308 and 310 and emerges into the central convergence 
chamber 324. As the product moves through the transmission passages 308 
and 310, it pushes and urges forward any product already occupying the 
passages 308 and 310 into the convergence chamber 324 and out of the 
discharge conduit 359. From discharge conduit 359, the product may be 
dispensed into receptacles, conduits, casings or packaging equipment 
connected to the discharge conduit 359 at sanitary ferrule 359a. 
During the operation of the consolidating manifold 22, the planar diverting 
gate 330, or the preferred crescent diverting gate 340, are positioned by 
their respective drive means to leave the first, cycling transmission 
passage 308 open, and to close the second, non-cycling passage 310 against 
backflow from the convergence chamber 324 and, when in a deaeration 
configuration, possible loss of negative air pressure from the hopper 14. 
The diverting gate such as planar gate 330 or, preferably crescent gate 
340, is pivoted in the other direction to close the first transmission 
passage 308 and open the second passage 310 once the first pump cylinder 
18 completes its pump cycle. The forward movement of the product through 
each transmission chamber 308 and 310 assists in the pivoting and sealing 
action of the gate during the pumping cycles. 
The pumping cycles described above are continuously repeated until the 
hopper 14 is substantially empty or the pumping operation is complete. The 
synchronized action of the pump cylinders 18 and 20 permits the rapid and 
continuous supply of large or small volumes of product to appropriate 
casings or containers. The use of the agitator 16 and a gravity feed to 
fill piston chambers 128 and 130 also enables the invention to efficiently 
and economically receive, process and dispense products that include 
relatively large pieces, such as whole muscle meats and relatively 
delicate or easily damaged products, such as poultry breasts, that are 
easily damaged by other pumping devices. 
The device 10 is easily disassembled for cleaning and sanitizing to satisfy 
industrial and governmental health standards. In the preferred embodiment, 
the rotatable sleeves 140 and 142 are removable for clearing and 
inspection, and are provided with a pair of opposed removal openings 430 
located proximate to the open sleeve forward ends 140a and 142a to assist 
in the removal procedure. 
To remove the rotatable sleeves 140 and 142, the manifold mounting plate 
292 is pivoted away from the housing front panel 34 to expose the 
rotatable sleeve forward ends 140a and 142a. The retaining plate sleeves 
258 and 260 are removed from the piston rods 234 and 236. As shown in 
FIGS. 15 and 16, a sleeve removal tool 432 may be inserted into each of 
the sleeves 140 and 142 to engage the removal openings 430 and the entire 
sleeves 140 and 142 with attached piston shafts 154 and 156 are pulled out 
of the cylindrical sleeve housings 90 and 92 of the device 10 along with 
the plunger plates 238 and 240 within the sleeves 140 and 142. 
The sleeve removal tool 432 shown in FIGS. 15 and 16 includes handle 434, 
extension shaft 436 and removal crossbar 438 attached at its midpoint to 
the extension shaft 436. The ends 440 of the crossbar 438 are shaped to 
fit within and engage the sleeve removal openings 430. The crossbar ends 
440 are provided with stop members 442, such as O-rings to prevent the 
ends 440 from contacting the interior of the sleeve housings 90 and 92. 
While the invention has been described by reference to certain specific 
descriptions and examples which illustrate preferred materials, 
configurations and conditions, including those pertaining to the 
processing of food products, it is understood that the invention is not 
limited thereto. Rather, all alternatives, modifications and equivalents 
within the scope and spirit of the invention so described are considered 
to be within the scope of the appended claims.