WO1991011616A1 - Improved system for pumping fluid - Google Patents

Improved system for pumping fluid Download PDF

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Publication number
WO1991011616A1
WO1991011616A1 PCT/US1990/006385 US9006385W WO9111616A1 WO 1991011616 A1 WO1991011616 A1 WO 1991011616A1 US 9006385 W US9006385 W US 9006385W WO 9111616 A1 WO9111616 A1 WO 9111616A1
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WO
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Application
Patent type
Prior art keywords
means
pumping
hydraulic
transfer chamber
fluid
Prior art date
Application number
PCT/US1990/006385
Other languages
French (fr)
Inventor
Dennis E. Swanson
Original Assignee
Wanner Engineering, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B43/00Machines, pumps, or pumping installations having flexible working members
    • F04B43/02Machines, pumps, or pumping installations having flexible working members having plate-like flexible members, e.g. diaphragms
    • F04B43/06Pumps having fluid drive
    • F04B43/073Pumps having fluid drive the actuating fluid being controlled by at least one valve

Abstract

An improved system for pumping difficult fluids such as abrasive slurries or chemicals includes a diaphragm-type pump which is driven through a hydraulic transmission arrangement. The pump includes a unique stop plate arrangement for protecting the diaphragm against underpressures which may be created in a hydraulic transfer chamber of the pump. The stop plate arrangement further acts asa check-type valve to limit the amount of working fluid that is allowed into the pump drive casing should the diaphragm fail. A pressure control valve is provided in the hydraulic transfer chamber for allowing fluid to escape should its pressure exceed a predetermined limit. Fluid expelled through the pressure control valve is not made up until the end of a piston stroke in the hydraulic transmission arrangement. As a result, fluid will escape through the pressure control valve during a first part of the piston stroke when the pump outlet is restricted or blocked. During the second return stroke of the piston cycle, an underpressure is created in the hydraulic transfer chamber which causes the hydraulic fluid to vaporize or cavitate. This creates a cooling effect which allows the pump to operate without damage when its outlet is blocked.

Description

IMPROVED SYSTEM FOR PUMPING FLUID

BACKGROUND OF THE INVENTION 1. Field of the Invention 5 This invention relates to industrial pumping systems for pumping slurries, abrasive or chemical solutions, or other fluids which are utilized in industrial applications. More particularly, this invention relates to an improved pumping cell for use in 10 such a system, which allows the system to be more efficient than those heretofore known and which will not be damaged when the pump outlet is restricted or blocked.

15 2. Description of the Prior Art

Contemporary industry requires pumps and pumping systems which permit the pumping of difficult fluids such as abrasives, hot solutions and fluids at high pressure. For example, pumping systems are needed

20 to handle abrasives and various liquids in the lawn care industry, sea water in reverse osmosis applications and reclaim water in car washes.

Because of the corrosive and abrasive nature of such fluids, conventional pumps are likely to be damaged

25. when their internal components are exposed to the working fluid. This is particularly the case for common gear, piston and vane-type pumps, which are likely to suffer severe corrosion or abrasion in such critical components as their cups, packings and mechanical seals.

30 As a result, industry has recently been turning to diaphragm-type positive displacement pumps such as those sold under the trademark Hydra-Cell™ by Wanner Engineering, Inc., which is the assignee of this invention. In the Hydra-Cell™ design, the solution 5 being pumped is separated from the pumping mechanism by a diaphragm. Because the solution never touches the pumping mechanism, these pumps can pump abrasive and hot liquids, and can run dry without damage.

Diaphragm-type pumps have proven themselves well suited for handling difficult fluids. For example, diaphragm-type pumps have been used to pump fluid in fertilizer distribution systems. In such a system, an operator may choose to turn off some of the distribution nozzles, such as when it is desired to distribute fertilizer over a narrower strip of land. When this happens, the pump outlet pressure increases, thereby increasing the amount of work that is absorbed by the mechanical elements of the pump. When the pump outlet is completely blocked, such as by shutting off all of the nozzles in a distribution system, the outlet pressure increases, possibly to the extent which might cause failure of the pump.

In order to combat this problem, fluid distribution systems using pumps have incorporated regulator valves which divert fluid from the outlet side of the pump if the outlet pressure becomes excessive. However, such valves also need adjustment, they wear out due to the effect of abrasive and corrosive fluids and they add to the overall cost and complexity of such systems.

Another feature of some prior art diaphragm- type pumps is a mechanism for adjusting the pumping stroke of the diaphragm. Although such mechanisms are necessary to adjust the volumetric output of the pump without changing its speed, they add substantially to the overall cost of the pump.

It is clear that there has existed a long and unfilled need in the prior art for an improved diaphragm-type pumping system which will not suffer damage when the outlet of the pump is restricted or blocked. It is also clear that a need exists for a diaphragm-type pump which can be volumetrically adjusted without changing its speed, that does not require an expensive stroke adjustment mechanism. SUMMARY OF THE INVENTION Accordingly, it is a first object of the invention to provide a diaphragm-type pumping system which will not suffer damage from overpressure when the outlet of the pump is restricted or blocked.

It is a second object of the invention to provide a diaphragm-type pump which can provide a variable volumetric output at a constant speed, without the use of an expensive stroke adjustment mechanism. In order to achieve these and numerous other objects of the invention, which will become apparent upon inspection of the following disclosure of a preferred embodiment, one basic aspect of the invention is a pumping cell in an apparatus which is used for pumping fluid, including structure for defining a pumping chamber; valve structure for permitting one-way outward flow from the pumping chamber to an outlet and for permitting one-way inward flow to the pumping chamber from an inlet; diaphragm structure for decreasing the volume of the pumping chamber when moved in a first direction and increasing the volume of the pumping chamber when moved in a second direction; structure for defining a hydraulic transfer chamber which is on an opposite side of the diaphragm structure from the pumping chamber; piston structure adapted for connecting to a source of motive power, the piston structure mounted for reciprocation between a first retracted position and a second inserted position in the transfer chamber so as to hydraulically transmit force to move the diaphragm structure; and pressure control structure for allowing hydraulic fluid to escape from the hydraulic transfer chamber when a predetermined pressure is exceeded, whereby the apparatus may continue to safely operate when the outlet is blocked. These and various other advantages and features of novelty which characterize the invention are pointed out with particularity in the claims annexed hereto and forming a part hereof. However, for a better understanding of the invention, its advantages, and the objects obtained by its use, reference should be made to the drawings which form a further part hereof, and to the accompanying descriptive matter, in which there is illustrated and described a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view of a system constructed according to a preferred embodiment of the invention, with certain components depicted in schematic form;

FIGURE 2 is a cross-sectional view of a portion of the system which is depicted in Figure 1;

FIGURE 3A is a fragmentary detailed cross- sectional view through a portion of the apparatus illustrated in Figure 2, shown in a first operational position; FIGURE 3B is a fragmentary detailed cross- sectional view of the same structure illustrated in Figure 3A, shown in a second operational position;

FIGURE 3C is a detailed fragmentary cross- sectional view of the structure illustrated in Figures 3A and 3B, shown in a third operational position; and FIGURE 3D is a fragmentary detailed cross- sectional view of the structure illustrated in Figures 3A-3C, shown in a fourth operational position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S) Referring now to the drawings, wherein like reference numerals designate corresponding structure throughout the views, and referring in particular to Figure 1, an improved fluid supply system 10 constructed according to a preferred embodiment of the invention includes an improved pump 12 and a distribution system 14. Distribution system 14 includes an outlet pipe 16 which leads from an outlet of pump 12 to a number of distribution branches 18. A valve 20 is provided in each of the distribution branches 18 for selectively shutting off the flow of fluid through the corresponding distribution branch. Nozzles (not shown) or further conduits may be provided on the opposite end of each of the valves 24 for distributing fluid in whatever manner that is required for a particular system.

As may be seen in Figure 1, pump 12 includes a drive section 22 and a fluid handling section 24. Both the drive section 22 and the fluid handling section 24 are physically supported relative to an underlying surface by means of a base plate 26. The base plate 26 has a plurality of mounting holes 28 defined therein which permits the base plate 26 to be permanently affixed to the support surface.

Drive section 22 is provided with an outer housing or casing 30 which is sealed so as to be capable of retaining a hydraulic fluid, for purposes which are described herein below. An input shaft 32 penetrates the outer casing 30 and is sealed for rotation with respect thereto. An inlet plate 34 is connected to fluid handling section 24 for supplying the working fluid to pump 12. A number of retaining bolts 36 are used to secure the fluid handling section 24 to drive section 22, as may best be seen in Figure 2.

Looking again to Figure 1, an oil fill inlet 38 is defined in an upper portion of the outer casing 30 in drive section 22. Oil fill inlet 38 is threaded so as to receive a complementary threaded plug 40. Threaded plug 40 is provided with a hexagonal recess in a top surface thereof which may be engaged with an alien wrench or similar tool to insert or remove plug 40 into the oil fill inlet 38. Referring now to. Figure 2, it will be seen that input shaft 32 is provided with a key way 44 or like spline connection for engaging a pulley or a sprocket. In this way, an external source of motive power may be coupled to input shaft 32 for driving pump 12. Input shaft 32 is rotatably supported relative to an inner support casing 48 of the pump 12 by a first roller bearing unit 46. As may be seen in Figure 2, inner support casing 48 is integral with the outer casing 30 of pump 12. A second roller bearing unit 50 supports a second portion of shaft 32 for rotation with outer casing 30. As may be seen in Figure 2, the axis of rotation of second roller bearing unit 50 is coincident with that of the first roller bearing unit 46 and with the axis of input shaft 32.

An eccentric sleeve member 52 is mounted about the input shaft 32 and is fixed to rotate with input shaft 32 by means of a pin 54, as is shown in Figure 2. Eccentric sleeve member 52 has a first outer surface 56 which is shaped as a cylinder projected about the axis of input shaft 32. The first cylindrical outer surface 56 is supported by second roller bearing unit 50. Eccentric sleeve member 52 further has a second outer surface 58 which is formed as a cylinder projected about an axis which is skewed with respect to the axis of input shaft 32. A third cylindrical outer surface 60 of eccentric sleeve member 52 is formed as a cylinder projected about the same axis as the axis of second eccentric cylindrical outer surface 58. A third roller bearing unit 64 is mounted on the second and third eccentric cylindrical outer surfaces 58, 60 and is used to support a wobble plate 62 for rotation with respect to the eccentric sleeve member 52. Wobble plate 62 has a forward surface upon which a trio of ball members 68 are supported. For purposes of clarity, only one of the ball members 68 is illustrated in Figure 2. Each of the ball members 68 are connected to provide motive power to a hydraulic pump drive mechanism 70, in a manner which will be described in greater detail below.

Turning now to Figures 3A-3D, the structure of each of the three(hydraulic pump drive mechanisms 70 will now be described. As may be seen in Figure 3A, the fluid handling section 24 of pump 12 has an inlet plenum 72 defined therein which is communicated with inlet pipe 34. An outlet plenum 74 is also defined in fluid handling section 24, and is communicated to the outlet pipe 16 of distribution system 14. Fluid flow between the hydraulic pump cell drive mechanism 70 and the inlet and outlet plenums 72, 74 is controlled by a valving arrangement 76, which is described in greater detail below.

As may be seen in Figure 3A, a piston member 78 is mounted for reciprocal movement within a cylinder 84 that is defined in inner support casing 48. Piston member 78 has a socket 80 defined therein for receiving ball member 68, as is perhaps best illustrated in Figure 2. A clip 82 retains ball member 68 within socket 80. An inlet port 85 is defined in cylinder 84 for communicating with the space which is defined within outer casing 30.

In operation, the space defined within outer casing 30 is filled with a hydraulic oil, which preferably has a weight of 5W to 30W. In the most preferred embodiment, the hydraulic oil within casing 30 has a weight of about 20W.

A radial oil inlet groove 86 is defined in piston member 78, as may be seen in Figure 3A. An inlet chamber 88 which is also defined in piston member 78 communicates with the radial inlet groove 86. A check valve 90 is provided in or adjacent to inlet chamber 88 to prevent fluid from flowing outwardly into inlet groove 86, for purposes which will be described in greater detail below. In the preferred embodiment, a washer 92 helps retain a ball which is used in check valve 90, as may be seen in Figure 3A.

Looking again to Figures 3A-3D, a valve cylinder member 94 is mounted to move with piston member 78. Valve cylinder member 94 has an interior cylindrical bore 96 defined therein and has an outer cylindrical surface 98. A plurality of ports 100 are defined in the wall of valve cylinder member 94 which defines the internal cylindrical bore 96 and the outer cylindrical surface 98.

A spring retainer member 102 is mounted for sliding movement with respect to piston member 78. Spring retainer member 102 slides with respect to an inner cylindrical surface 104 of piston member 78 and is sealed with respect thereto by means of an O-ring 106. The spring retainer member 102 has an inner cylindrical surface 116 which has a first cylindrical portion and a second cylindrical portion of reduced cross section. The second cylindrical portion of inner surface 116 is sealed for sliding movement with respect to the outer cylindrical surface 98 of valve cylinder member 94 by means of an O-ring 108. Spring retainer member 102 further has an inwardly directed flange 110 that bears against an end surface of valve cylinder member 94. As may further be seen in Figures 3A-3D, a helical compression spring 114 is positioned between a seating surface 112 on spring retainer member 102 and a corresponding retaining surface on the inner support casing 48. Spring 114 is thus positioned within a hydraulic transfer chamber 118 that is defined within cylinder 84 between piston member 78 and inner support casing 48. As may be seen clearly in Figure 3A, an annular inlet passage 120 is defined between the outer cylindrical surface 98 of valve cylinder member 94 and the inner cylindrical surface 116 of spring retainer member 102. When check valve 90 is open, inlet passage 120 is communicated with inlet chamber 88 and thus with the radial inlet groove 86, as is shown in Figure 3A. inlet passage 120 further communicates with the plurality of ports 100 which are defined within the wall of valve cylinder member 94. A valve plunger member 122 having a piston head portion 124 and a plunger portion 128 is positioned coaxially with piston member 78, as is shown in Figures 3A-3D. Piston head portion 124 is sealingly positioned for sliding movement within the internal cylindrical bore 96 of valve cylinder member 94. A spring 125 acts to bias piston head portion 124 relative to spring retainer member 102 in a direction which urges the piston head portion 124 into the internal cylindrical bore 96.

An axial passage 126 is defined within valve plunger member 122 and communicates with a plurality of ports 130 which extend radially within the plunger portion 128 of valve plunger member 122. Ports 130 communicate axial passage 126 with the transfer chamber 118. As a result, hydraulic oil within transfer chamber 118, ports 130, axial passage 126 and the internal cylinder 96 of valve cylinder member 94 will be isobaric. A space 135 which is defined by the outer surface of plunger portion 128 and the wall of internal bore 96 will also be of equal pressure with transfer chamber 118, because it is communicated with one of the ports 130. When this space 135 is aligned with the ports 100, hydraulic oil in ports 100 and in annular inlet passage 120 will also communicate and be of equal pressure with the oil in space 135, ports 130, axial passage 126 and transfer chamber 118.

As is also shown in Figures 3A-3D, a flexible diaphragm 132 is positioned between the inner support casing 48 of drive section 22, and an inner casing 133 of fluid handling section 24. Diaphragm 132 is engaged at its central portion by a stop plate 134 and a flange member 136. The central part of diaphragm 132 is thus securely gripped between a forward surface of stop plate 134 and a rear surface of flange 136. A bolt 138 extends through flange 136 and into a threaded recess which is defined in an in portion of the plunger portion 128 of valve plunger member 122. The shoulder on plunger portion 128 of valve plunger member 122 limits sliding movement of stop plate 134 relative to valve plunger 122. Looking now to Figure 3B, a stop surface 142 is defined on inner support casing 48 for supporting a first portion of diaphragm 132 when distant member 78 is in a retracted position. At the same time, a second remaining portion of diaphragm 132 is supported on a forward surface of stop plate 134. A rear surface 140 of stop plate 134 is constructed to seal against an inner annular portion of stop surface 142, as may be seen in Figure 3A.

In fluid handling section 24, a pumping chamber 144 is defined in inner casing 133 on one side of diaphragm 132. An inlet valve 146 is mounted in an inlet passage which communicates pumping chamber 144 with inlet plenum 72. Inlet valve 146 includes a movable valve member 148 which is biased toward a valve seat 152 by a helical compression spring 150. Similarly, an outlet valve 154 is disposed within an outlet passage communicating pumping chamber 144 with outlet plenum 74. Outlet valve 154 includes a movable valve member 156 having a surface for sealing against a valve seat 160. A spring 158 biases movable valve member 156 toward valve 160.

A pressure control valve 164 is defined in drive section 22 for releasing hydraulic oil from transfer chamber 118 when a predetermined pressure is exceeded. Pressure control valve 164 includes a ball member 166 which is biased toward a seating surface by a spring 170. A threaded plug 168 having a hexagonal recess defined in an end surface thereof bears against biasing spring 170 to adjust the force which is applied to ball member 166. Hexagonal recess 172 may be engaged by an alien wrench or like tool.

The operation of an improved fluid supply system 10 constructed to the preferred embodiment of the invention will now be described. In a first mode of operation, all of the valves 20 in distribution system 14.are open, and fluid flow is not impeded through outlet pipe 16. As input shaft 32 is turned, the eccentric sleeve member 52 is also caused to turn. As a result, the second and third eccentric cylindrical outer surfaces 58, 30 on eccentric sleeve member 52 move in a precessive manner. This causes wobble plate 62 to tilt alternatively in a forward and reverse direction. As a result, ball member 68 is driven in a direction which has a component of motion in the axial direction of piston member 78, thus inserting and retracting piston member 78 within cylinder 84. When piston member 78 is fully retracted, as is illustrated in Figure 3A, oil inlet port 85 is aligned with radial inlet groove 86 in piston member 78. This allows hydraulic fluid contained within outer casing 30 to be drawn into transfer chamber 118 via inlet chamber 88, annular inlet passage 120, ports 100, space 135, and through axially passage 126 and ports 130. As piston member 78 is driven into cylinder 84, against the biasing of helical compression spring 114, the hydraulic fluid in transfer chamber 118 moves the diaphragm 132 in a forward direction into the pumping chamber 144. The pressure is equal in transfer chamber 118 and pumping chamber 144 except for the spring load created by spring 125. This causes the working fluid in pumping chamber 144 to be expelled through outlet valve 154 into outlet plenum 74. The fluid is then forced through outlet plate 16 into the various branches 18 of distribution system 14 to its eventual destination. During this forward stroke of piston member 78, pressure in transfer chamber 18 does not become so excessive that pressure control valve 164 is caused to open. At the end of the forward stroke, the piston 78 and diaphragm 132 will be in the position which is illustrated in Figure 3B. As ball member 68 again retracts, the piston member will likewise retract under the force provided by helical compression spring 114. This causes diaphragm 132 to likewise retract, thus expanding the volume of pumping chamber 144 and drawing working fluid through inlet valve 146 from inlet plenum 72. This continues until the first portion of diaphragm 132 is flush against stop surface 142, and the rear surface 140 of stop plate 134 likewise bears against stop surface 142.

In order to prevent overfilling of transfer chamber 118, which might damage diaphragm 132, valve plunger member 122 regulates the amount of hydraulic fluid that is allowed to enter transfer chamber 118 from annular inlet passage 120. When transfer chamber 118 becomes filled with more fluid than is illustrated in Figure 3A, diaphragm 132 is displaced away from piston member 78, which causes the piston head portion 124 of valve plunger member 122 to extend telescopingly with respect to the internal cylindrical bore 96 of valve cylinder member 94. As a result, piston head portion 124 covers ports 100, thus blocking any entry of hydraulic oil into space 135 and ports 130. Ports 100 stay so blocked until the excess oil escapes from transfer chamber 118, at which point valve plunger member 122 is biased via spring 125 to the position indicated in Figure 3A for normal operation. The function of valve.plunger member 122 is thus similar to that described in U.S. Patent 3,884,598 to Wanner, the disclosure of which is incorporated herein by reference. According to one principal advantage of the invention, the stop plate 134 will seal against stop surface 142 in the manner of a check valve should the diaphragm 132 suddenly rupture or fail. As a result, the amount of working fluid allowed into drive section 22 during such failure will be limited. In a second mode of operation, valves 20 in the distribution system are closed. As mechanical power continues to be transmitted to input shaft 32, piston member 78 is caused to continue to reciprocate within cylinder 84. Because valves 20 are closed, fluid is not permitted to pass through the distribution system 14. As a result, fluid cannot escape from pumping chamber 144, and diaphragm 132 is unable to move from its retracted position against stop surface 142. As is shown in Figure 3C, forward movement of piston member 78 compresses the hydraulic fluid in transfer chamber 118 to a pressure which is in excess of the pressure needed to open pressure control valve 164. At this time, check valve 90 effectively reduces the compression ratio of the transfer chamber 118 by blocking rearward flow of hydraulic fluid.

As pressure control valve 164 opens, fluid from transfer chamber 118 is allowed to escape into the space defined within outer casing 30. As the fluid is compressed, it heats somewhat. The fluid which escapes into the space within casing 30 dissipates some of this heat through the casing 30 into the atmosphere. As piston member 78 again retracts, the hydraulic fluid in transfer chamber 118 is forced to expand in volume. However, pressure control valve 164 is at this point closed, and inlet groove 86 is not aligned with the oil inlet port 85. As a result, transfer chamber 118 is not in communication with any sources of hydraulic fluid.

As a result, the hydraulic fluid in transfer chamber 118 is caused to cavitate or pass into a vaporized state 162, as is illustrated in Figure 3D. As this underpressure occurs, diaphragm 132 is protected by stop plate 134, which remains tightly sealed against stop surface 142. At the end of the rearward stroke, groove 86 again becomes aligned with oil inlet port 85, and makeup oil is drawn into transfer chamber 118.

As the hydraulic fluid flashes to vapor or cavitates during the retraction stroke, the energy required for such a phase change cools the piston member 78, cylinder 84 and the hydraulic fluid itself. This cooling effect allows pump 12 to be operated without overheating, even if the outlet pipe 16 is completely blocked. The vapor is turned back to a liquid during the compression stroke. As a result, an improved fluid supply system according to the invention can operate without overheating or damage to the diaphragm when all outlets are shut off, without the need for any additional valving. In a third mode of operation, a certain number of the valves 20 may be closed, while the rest remain open. This will restrict but not completely block flow through outlet plate 16, which causes only partial cavitation in transfer chamber 118 during the return stroke of piston member 78. In this mode of operation, the diaphragm 132 is again protected during the phase of the piston stroke in which cavitation is induced. The cooling effect described above is also present, but reduced according to the number of valves 20 which are ope .

It is clear that a system 10 according to the invention provides industry a simpler, longer lasting and more efficient tool for pumping difficult fluids. It is to be understood, however, that even though numerous characteristics and advantages of the present invention have been set forth in the foregoing description, together with details of the structure and function of the invention, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size and arrangement of parts within the principles of the invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Claims

WHAT IS CLAIMED IS;
1. A pumping cell in an apparatus which is used for pumping fluid, comprising: means for defining a pumping chamber; valve means for permitting one way outward flow from said pumping chamber to an outlet and for permitting one way inward flow to said pumping chamber from an inlet; diaphragm means for decreasing the volume of said pumping chamber when moved in a first direction and increasing the volume of said pumping chamber when moved in a second direction; means for defining a hydraulic transfer chamber which is on opposite side of said diaphragm means from said pumping chamber; piston means adapted for connecting to a source of motive power, said piston means mounted for reciprocation between a first retracted position and a second inserted position in said transfer chamber so as to hydraulically transmit force to move said diaphragm means; and pressure control means for allowing hydraulic fluid to escape from said hydraulic transfer chamber when a predetermined pressure is exceeded whereby the apparatus may continue to safely and efficiently operate at a reduced volumetric flow when the outlet is restricted.
2. An apparatus according to claim 1, further comprising means for resupplying hydraulic fluid to said hydraulic transfer chamber, said resupplying means being operational only when said piston means is in said first retracted position, whereby an underpressure and resultant cavitation is induced in said hydraulic transfer chamber when said apparatus is operated with the outlet blocked.
3. An apparatus according to claim 2, wherein said resupplying means comprises a port defined in a portion of said hydraulic transfer chamber defining means in which said piston means is mounted to reciprocate, said port being in communication with a source of hydraulic fluid; and a passage defined in said piston for communicating said port to said hydraulic transfer chamber when said piston means is in the first retracted position;
4. An apparatus according to claim 3, further comprising a check valve disposed in said passage for preventing hydraulic fluid from flowing from said hydraulic transfer chamber back through said passage during compression.
5. An apparatus according to claim 2, further comprising means for protecting said diaphragm means against damage when an underpressure is created in said hydraulic transfer chamber.
6. An apparatus according to claim 4, wherein said protecting means comprises a stop surface for supporting a first portion of said diaphragm means when said diaphragm means reaches its limit of movement in the second direction, and a stop plate secured to a second, remaining portion of said diaphragm means, said stop plate being configured to seal against said stop surface when said diaphragm means reaches its limit in the second direction, whereby said diaphragm means is protected against direct exposure to an underpressure.
7. An apparatus according to claim 1, further comprising means to prevent said transfer chamber from overfilling with hydraulic oil.
8. An apparatus for pumping fluid, comprising: a fluid handling section having an inlet plenum and an outlet plenum defined therein; a drive section having an outer casing which is adapted for holding a hydraulic fluid, said drive section comprising a shaft mounted for rotation with respect to and extending from said outer casing, said shaft being adapted for connection to a source of motive power; a plurality of pumping cells for pumping fluid from said inlet plenum to said outlet plenum; and means for transmitting mechanical energy from said shaft to said pumping cells; wherein each of said pumping cells comprises: means for defining a pumping chamber; valve means for permitting one-way outward flow from said pumping chamber to said outlet plenum and for permitting one-way inward flow to said pumping chamber from said inlet plenum; diaphragm means for decreasing the volume of said pumping chamber when moved in a first direction and increasing the volume of said pumping chamber when moved in a second direction; means for defining a hydraulic transfer chamber which is on an opposite side of said diaphragm means from said pumping chamber; piston means adapted for connecting to said transmitting means, said piston means mounted for reciprocation between a retracted first position and a second inserted position in said transfer chamber so as to hydraulically transmit force to move said diaphragm means; and pressure control means for allowing hydraulic fluid to escape from said hydraulic transfer chamber when a predetermined pressure is exceeded, whereby the apparatus may continue to safely and efficiently operate at a reduced volumetric flow when the outlet is restricted.
9. An apparatus according to claim 8, wherein said transmitting means comprises wobble plate means for converting rotary movement of said shaft into linear motion which is transmitted to said piston means.
10. An apparatus according to claim 8, wherein each of said pumping cells further comprises means for resupplying hydraulic fluid to said hydraulic transfer chamber from the space defined within said outer casing, said resupplying means being operational only when said piston means is in said first retracted position, whereby an underpressure and resultant cavitation is induced in said hydraulic transfer chamber when said apparatus is operated with the outlet blocked.
11. An apparatus according to claim 10, wherein said resupplying means comprises a port defined in a portion of said hydraulic chamber defining means and which said piston means is mounted to reciprocate, said port being in communication with said space defined within said outer casing; and a passage defined in said piston for communicating said port to said hydraulic transfer chamber when said piston means is in the first retracted position.
12. An apparatus according to claim 11, wherein each of said pumping cells further comprises a check valve disposed in said passage for preventing hydraulic fluid from flowing from said hydraulic transfer chamber back through said passage during compression.
13. An apparatus according to claim 10, further comprising means for protecting said diaphragm means against damage when an underpressure is created in said hydraulic transfer chamber.
14. An apparatus accordir- to claim 12, wherein said protecting means comprise a stop surface for supporting a first portion of said diaphragm means when said diaphragm means reaches its limit of movement in the second direction, and a stop plate secured to a second, remaining portion of said diaphragm means, said stop plate being configured to seal against said stop surface when said diaphragm means reaches its limit in a second direction, whereby said diaphragm means is protected against direct exposure to an underpressure.
15. An apparatus according to claim 8, further comprising means to prevent said transfer chamber from overfilling with hydraulic oil.
16. A system for pumping and distributing fluid, comprising: a distribution system including means for selectively limiting passage of fluid through at least one portion of said system; means for pumping fluid into said distribution system, said pumping means comprising a fluid handling section having an inlet plenum and an outlet plenum defined therein; and a drive section having an outer casing which is adapted for holding hydraulic fluid, said drive section comprising a shaft mounted for rotation with respect to and extending from so that it said outer casing, said shaft being adapted for connection to a source of motive power; a plurality of pumping cells for pumping fluid from said inlet plenum to said outlet plenum; and means for transmitting mechanical energy from said shaft to said pumping cells; wherein each of said pumping cells comprises; means for defining a pumping chamber; valve means for permitting one-way outward flow from said pumping chamber to said outlet plenum and for permitting one-way inward flow to said pumping chamber from said inlet plenum; diaphragm means for decreasing the volume of said pumping chamber when moved in a first direction and increasing the volume of said pumping chamber when moved in a second direction; means for defining a hydraulic transfer chamber which is on an opposite side of said diaphragm means from said pumping chamber; piston means adapted for connecting to said transmitting means, said piston means being mounted for reciprocation between a retracted first position and a second inserted position and said transfer chamber so as to hydraulically transmit force to move said diaphragm means; and pressure control means for allowing hydraulic fluid to escape from said hydraulic transfer chamber when a predetermined pressure is exceeded, whereby the apparatus may continue to safely and efficiently operate at a reduced volumetric flow when the outlet is restricted.
17. An apparatus according to claim 16, further comprising means to prevent said transfer chamber from overfilling with hydraulic oil.
PCT/US1990/006385 1990-02-01 1990-11-05 Improved system for pumping fluid WO1991011616A1 (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1998029662A1 (en) * 1996-12-31 1998-07-09 Elan Corporation, Plc A device for generating a pulsatile fluid drug flow
EP1625301A2 (en) * 2003-05-16 2006-02-15 Wanner Engineering, Inc. Diaphragm pump
WO2008137515A1 (en) * 2007-05-02 2008-11-13 Wanner Engineering, Inc. Diaphragm pump position control with offset valve axis
US7758321B2 (en) 2004-07-21 2010-07-20 Smc Kabushiki Kaisha Pump apparatus
KR20150094099A (en) * 2014-02-10 2015-08-19 문일 Micro Pump including check valve
EP3096013A1 (en) * 2003-05-16 2016-11-23 Wanner Engineering, Inc. Diaphragm pump
CN107002656A (en) * 2014-11-18 2017-08-01 利乐拉瓦尔集团及财务有限公司 A pump, a homogenizer comprising said pump and a method for pumping a liquid product

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3775030A (en) * 1971-12-01 1973-11-27 Wanner Engineering Diaphragm pump
US4019837A (en) * 1975-05-30 1977-04-26 Graco Inc. Pressure unloading apparatus for a diaphragm pump
US4050859A (en) * 1976-07-01 1977-09-27 Graco Inc. Diaphragm pump having a reed valve barrier to hydraulic shock in the pressurizing fluid
US4068982A (en) * 1976-12-20 1978-01-17 Graco Inc. Charge control valve and piston assembly for diaphragm pump

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3775030A (en) * 1971-12-01 1973-11-27 Wanner Engineering Diaphragm pump
US4019837A (en) * 1975-05-30 1977-04-26 Graco Inc. Pressure unloading apparatus for a diaphragm pump
US4050859A (en) * 1976-07-01 1977-09-27 Graco Inc. Diaphragm pump having a reed valve barrier to hydraulic shock in the pressurizing fluid
US4068982A (en) * 1976-12-20 1978-01-17 Graco Inc. Charge control valve and piston assembly for diaphragm pump

Cited By (13)

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WO1998029662A1 (en) * 1996-12-31 1998-07-09 Elan Corporation, Plc A device for generating a pulsatile fluid drug flow
EP1625301A2 (en) * 2003-05-16 2006-02-15 Wanner Engineering, Inc. Diaphragm pump
EP1625301A4 (en) * 2003-05-16 2007-10-03 Wanner Engineering Diaphragm pump
EP3096013A1 (en) * 2003-05-16 2016-11-23 Wanner Engineering, Inc. Diaphragm pump
DE102005033192B4 (en) * 2004-07-21 2014-05-15 Smc K.K. pumping device
US7758321B2 (en) 2004-07-21 2010-07-20 Smc Kabushiki Kaisha Pump apparatus
CN101743403B (en) 2007-05-02 2012-08-29 万纳工程公司 Diaphragm pump and diaphragm pump position control method with offset valve axis
US7665974B2 (en) 2007-05-02 2010-02-23 Wanner Engineering, Inc. Diaphragm pump position control with offset valve axis
WO2008137515A1 (en) * 2007-05-02 2008-11-13 Wanner Engineering, Inc. Diaphragm pump position control with offset valve axis
KR101595980B1 (en) 2014-02-10 2016-02-19 문일 Micro Pump including check valve
KR20150094099A (en) * 2014-02-10 2015-08-19 문일 Micro Pump including check valve
CN107002656A (en) * 2014-11-18 2017-08-01 利乐拉瓦尔集团及财务有限公司 A pump, a homogenizer comprising said pump and a method for pumping a liquid product
US10100830B2 (en) 2014-11-18 2018-10-16 Tetra Laval Holdings & Finance S.A. Pump, a homogenizer comprising said pump and a method for pumping a liquid product

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