US3227095A - Variable stroke pump - Google Patents

Variable stroke pump Download PDF

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US3227095A
US3227095A US285507A US28550763A US3227095A US 3227095 A US3227095 A US 3227095A US 285507 A US285507 A US 285507A US 28550763 A US28550763 A US 28550763A US 3227095 A US3227095 A US 3227095A
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segment
pump
exhaust
piston
head
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US285507A
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Tom H Thompson
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Daytona Thompson Corp
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Daytona Thompson Corp
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26Control
    • F04B1/30Control of machines or pumps with rotary cylinder blocks
    • F04B1/32Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block
    • F04B1/324Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block by changing the inclination of the swash plate
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/20Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F04B1/2014Details or component parts
    • F04B1/2042Valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/20Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F04B1/2014Details or component parts
    • F04B1/2064Housings
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/20Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F04B1/2014Details or component parts
    • F04B1/2078Swash plates
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/20Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block
    • F04B1/22Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis having rotary cylinder block having two or more sets of cylinders or pistons
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04BPOSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26Control
    • F04B1/30Control of machines or pumps with rotary cylinder blocks
    • F04B1/303Control of machines or pumps with rotary cylinder blocks by turning the valve plate

Definitions

  • Wobble plate type pumps and compressors are highly desirable structures in that they are capable of maintaining variable working pressures and variable capacities of volume throughputs. 'Dhe cant of the wobble plate establishes its capacity and if desired to stop pumping, it is merely erected to a zero pump position.
  • Pressure of the pump is controlled by the force with which the wobble plate is biased to its canted working position.
  • This can be loaded with a calibrated spring or equivalent mechanism that has an established breakover point. Accordingly, automatically controlled working pressures are provided by the breakover point of the biasing means or mechanism employed.
  • Water hammer This is a destructive vibration which is encountered as the mechanism rotates and liquid is delivered from the exhaust manifold during passage of the piston cylinder unit from the exhaust manifold across the separating segment to the intake manifold for further pickup of fluid.
  • a further object is to provide a wobble plate pump embodying several novel features of construction, improved simplicity and characterized by long life.
  • a further object is to provide a novel wobble plate pump embodying a unique separating segment between the inlet and exhaust manifolds that is so constructed to eliminate vibration as by fluid hammer.
  • a further object is to provide a wobble plate pump characterized by a unique piston guiding arrangement that renders the pistons non-rotatable.
  • a further object is to provide a novel wobble plate pump having a casing of controlled axial expansion to compensate for temperature changes within the unit and therefore maintain operating tolerances.
  • FIGURE 1 is an axial section view of a pump of invention
  • FIGURE 1a is a fragmentary section along line la-la of FIGURE 1;
  • FIGURE 1b is a fragmentary elevation view partly in section of an alternate embodiment of the spacer sleeve arrangement
  • FIGURE 10 is a fragmentary section taken along the line 1cc of FIGURE 12:;
  • FIGURE 2 is a right end elevation view of FIGURE 1;
  • FIGURE 3 is a section view taken along the line 33 of FIGURE 1;
  • FIGURE 4 is a section view taken along the line 4--4 of FIGURE 1, but with the Wobble plate in the null or true transverse position as distinguished from FIGURE 1;
  • FIGURE 5 is a fragmentary elevation taken along the line 5-5 of FIGURE 4;
  • FIGURE 6 is an elevation view of a pump head as along the line 66 of FIGURE 1, showing details of a first embodiment separating segment in accordance with the invention
  • FIGURE 7 is a section view taken along the line 7-7 of FIGURE 6;
  • FIGURE 8 is an enlarged fragmentary section view similar to FIGURE 7 but of the segment only to better show details
  • FIGURE 9 is an enlarged fragmentary elevation similar to FIGURE 6, showing a second embodiment of separating segment
  • FIGURE 10 is a perspective view of a third embodiment separating segment
  • FIGURE 11 is a fragmentary section view showing the third embodiment separating segment of FIGURE 10 mounted in a pump end plate on head;
  • FIGURE 12 is a fragmentary elevation of the third embodiment segment mounted in a head, showing stop pin and calibrated control spring;
  • FIGURE 13 is a fragmentary elevation of the interior face of a head similar to FIGURE 6, but showing opposed segments providing a reversible pump;
  • FIGURE 14 is a fragmentary elevation view of a fourth embodiment segment mounted in a head and showing stop pin and calibrated control spring;
  • FIGURE 15 is a fragmentary section View taken along the line 15-15 of FIGURE 14-;
  • FIGURE 16 is a fragmentary elevation view of the interior face of a pump head similar to FIGURE 14, but showing that segment arrangement modified to provide a reversible pump structure;
  • FIGURE 17 is a fragmentary elevation view of a fifth embodiment segment mounted in a pump head
  • FIGURE 18 is a section along line 18-18 of FIG- URE 17;
  • FIGURE 19 is a fragmentary elevation view of a sixth embodiment segment mounted in a pump head
  • FIGURE 20 is a fragmentary section view taken along the line lit-20 of FIGURE 19;
  • FIGURE 21 is a fragmentary elevation view of a seventh embodiment segment mounted in a pump head and showing calibrated spring and stop, this view greatly enlarged;
  • FIGURE 22 is an elevation along the line 22-22 of FIGURE 21;
  • FIGURE 23 is an enlarged axial section of a first embodiment piston of invention
  • FIGURE 24 is an elevation view taken along the line 2424 of FIGURE 23;
  • FIGURE 25 is an enlarged fragmentary axial section view of a second embodiment piston
  • FIGURE 26 is an end elevation taken along the line 2626 of FIGURE 25;
  • FIGURE 27 is an enlarged axial section view of a third embodiment piston
  • FIGURE 28 is an elevation view along the line 2828 of FIGURE 27;
  • FIGURE 29 is a side elevation, partly in section, of a fourth embodiment piston
  • FIGURE 30 is a side elevation practically actual size, and partly in section, of a fifth embodiment piston.
  • FIGURE 31 is an end elevational view of the piston assembly illustrated in FIGURE 30.
  • the pump is designated by the reference numeral t) and axially is constructed as a housing 52 of square but annular shape as indicated in FIGURE 3.
  • the pump head At each end, as best shown in FIGURE 1, there is a pump head.
  • the right hand head As viewed in FIGURE 1, the right hand head is designated 54 and the left hand head 56.
  • the right hand head is provided with a stepped bore 58 and the left hand head with a stepped bore 6t? to receive antifriction bearings.
  • a drive shaft 62 extends through the bores 58 and 60.
  • a ball bearing 64 in the larger diameter portion.
  • the shaft d2 is stepped as at 66 to be received in the bearing 64.
  • a sleeve spacer 67 is inserted from the outside and is retained in place by an end cap 68, also shown in FIGURE 21 that is retained in place by bolts '79. It will be evident that the end cap 68 presses against the sleeve spacer 67 and thus retains the bearing 64 in proper position.
  • An O-ring grooved system 72 seals the end plate 68 against leakage.
  • a cap 74 is threaded into the right end of the shaft 62 and thus the shaft is held to the right end head 54 after initial assembly, to facilitate further assembly and attachment of r the left hand end mechanism.
  • left hand head 56 is provided with a stepped bore 60 through which the shaft 62 is passed.
  • a roller bearing '76 is positioned around the shaft, heavier to withstand the radial forces imposed by a drive pulley 73 attached to the left most end of shaft 62.
  • an end cap 86 of generally circular configmration but heavier in axial thickness than the end cap 68 on the other end of the pump is provided. This is coaxially bored at 82 to receive the shaft 62 and the bore is stepped to receive a portion of the roller bearing '76 and the bearing retainer and seal 84 as indicated. Bolts 86 are passed through suitable bores in the end cap 80 and into the left end head 56 to provide the assembly. An O-ring groove system 87 is provided in the cap SIB to seal against leakage.
  • the drive pulley i8 is of arcuate section and includes a V-groove 88 in the periphery for connection to the V-belt, as of an automobile fan belt for power transmission purposes.
  • end plates are provided with upper and lower horizontal cross bores 98 and 100. These are suitably produced by drilling operation followed by placement of plugs to seal the left end as indicated at 192.
  • each head Coaxially of the shaft 62, there is provided in the inside face of each head an annular groove 104, as will best be understood by reference to FIGURES 3 and 3a.
  • a vertically disposed bore is drilled from the top edge downwardly to intersect the intake portion 106, and an exhaust bore, also of vertical configuration and designated 112, extends from the bottom edge up to intersect the exhaust segment 108 of the groove 104. After the borings are made, they are suitably capped, as indicated by reference numerals 102.
  • FIGURE 1 A word at this point to clarify FIGURE 1.
  • the annular groove 104 has not been shown in FIGURE 1, because the section was taken through what would be a separating segment and thus would be solid metal as indicated.
  • inlet cross-over tubes 118 extend between the right and left hand heads 54, 56, and two lower cross-over tubes 120 are similarly disposed at the bottom of the unit, functioning as outlet cross-over tubes as will be hereinafter apparent.
  • the unit is retained together axially or longitudinally by through bolts 128 having nuts 130 on the left end thereof. Note the heads of the bolts in FIGURE 2. It should be noted at this point that full pressure of the bolts is not taken by the O-rings 126. Instead, the ends of the housing 52, designated 53, receives the full bolt thrust. Thus, the O-rings 126 are not extruded and, accordingly, an effective seal is provided. It will be noted that leakage from the sump defined by the interior of the housing is prevented by an O-ring groove system 132 formed in the face of each end 53. Thus, when the bolts 128 are drawn up tight, the cross-over tubes 118 and 120, and the housing and each head are effectively sealed. It will be evident that the substantial convenience of economy of manufacture and assembly is provided in accordance with the use of the cross-over tube structure.
  • FIGURE 3 To view the cylinder rotor in plan, refer to FIGURE 3 and note that it is of circular shape, beveled as at 138 to provide clearance for the Wobble plate 140.
  • FIG- URE 1 The manner in which the rotors 134, 136 are staked or fastened to shaft 62 is illustrated at the left side of FIG- URE 1, wherein a Woodrulf key 90 cooperates with an appropriate slot in the shaft 62 and a groove in a bore of rotor 135.
  • the bore is designated by the reference numeral 141, FIGURE 1.
  • each cylinder rotor or block 134, 136 is provided with seven circumferentially spaced cylinder bores 142. These receive the respective ends of double-ended pistons to be later described in several embodiments.
  • a septagonal spacer sleeve 144 extends between the innner faces of the blocks 134, 135.
  • the seven faces of the septagonal spacer sleeve designated 146 cooperate with flats on the cylinders to prevent rotation thereof.
  • a section view of the spacer sleeve 146 is provided, showing the seven sides.
  • the terminal end of the spacer sleeve 144 is provided with a plurality of radially extending notches 143 to release high pressure fluid that crawls along the shaft 62 from between the heads 54, 56 and rotor faces and releases this high pressure leakage to the sump.
  • spacer sleeve 144 is not necessarily locked to the shaft because it will be retained against the rotation relative thereto by the fact that the flats of the piston are against it and these cannot move, because the blocks 134, 136 are locked to the shaft by means of the keys 90, illustrated at the left side in FIG- URE 1.
  • the keys 90 by which the rotors 134, 136 are rotationally locked to the shaft 62 do not prevent axial movement. Also by virtue of the release notches 148, the pressure developed between the right and left hand heads and the right and left hand blocks will be effective to press the blocks tight against the ends of the spacer sleeve. This is effective to provide an automatic overall dimension at the exterior 6 faces of the blocks to cooperate with the dimension established between the right and left hand heads and the ends of the housing 52.
  • the housing is of aluminum for expansion when the pump heats up under load. This automatically moves the heads out to provide proper clearance with the cylinder blocks, preventing galling and scrubbing and yet maintains the close clearances.
  • a typical dimension between the inner faces of right and left hand heads will be about two ten thousandths of an inch greater than the dimension between the exterior faces of the right and left hand blocks when pressed tightly against the ends of the spacer sleeve.
  • the key does not prevent the block 136 from axial movement on shaft 62. Since the septagonal spacer sleeve 144 is also not locked against axial movement, the unit rotor 136, spacer 144, rotor 134, automatically is centered between the heads providing one ten thousandth of an inch clearance at each end.
  • spacer sleeve Referring to FIGURES 1b and 10, there is illustrated an alternate embodiment spacer sleeve whereby the sleeve is split and a biasing spring is interposed to force the rotors into close relation with the inner faces of the right and left hand heads 54, 56.
  • the two halves of the spacer sleeve are designated by the reference numeral 150 and at the ends abut the inner faces of the blocks 13 4, 136 as previously indicated.
  • Spring 152 is interposed between the two halves 150 and thus biases the halves against the blocks and the blocks in turn toward the respective pump heads.
  • index pins 154 received half and half by a sleeve half 150 and a cylinder rotor 134, 136, provides proper orientation of the bearing surfaces or flats of the separator sleeve halves with flats of the pistons to prevent anti-rotation.
  • the spring 152 can be omitted and the two halves 159 made longer so that they abut at a joint at the middle.
  • the release notches 148 can be omitted at each end or reduced in size, so that the high pressure will bleed partially between the spacer and the cylinder blocks and partially through the joint at the center of the split separator segment. This will hydraulically bias the cylinder blocks toward the pump heads and will be effective as the pressure increases to automatically press the blocks more firmly toward the heads and thus retain the increased pressure.
  • pistons 155 are suitably made from hexagon rod stock and are turned and ground at the ends to provide a highly accurate mate for the previously mentioned bores 142.
  • the piston ends are designated by the reference numeral I56.
  • the piston is provided with a generally U-shaped notch 158 to receive a slotted ball 160.
  • the wobble plate shell comprises two mirror image halves designated by the reference numeral 162, FIGURE 5.
  • these halves 162 have mating annular walls 164, provided with mating bores 166 to receive recessed head through bolts 168 for attachment.
  • the radial walls 170 of the halves 162 are each provided with openings 172 to accommodate the pistonbiock, etc., assembly and shaft 62.
  • the halves 162 are provided with semi-circular mounting segments 174 attached by weld 176, FIGURE 5. These do not produce a full circle and thereby leave a notch 178 to receive a control spring assembly. Spaced 90 from the notch 178, there is a bore 180 to receive a retainer pin 182. This will be evident in both FIGURES and 4. These hold the biasing springs in the notches 178.
  • the biasing or control spring mechanism is of two parts and includes a back-up bar 184 lying along one side of the notch 178 and a scroll-like control spring 186 cradled along the other side of the notch.
  • each pin bushing 192 receives a pivot pin 194 that is notched on the inner end to straddle the retainer pin 182, the back-up bar 184- and scroll spring 186.
  • the inner end of the bushing of course fits into the circular opening provided by the two semi-circular mounting segments 174-, see FIGURE 5.
  • the pivot pin 194 bottoms the side or periphery of the halves 162 and thus does not cramp either the retainer pin 182 or the bar 184, scroll spring 186 assembly.
  • the outer end of the pivot pin provides an effective pivot within the pin bushing 192.
  • a disc-like bush cap 196 fits against the outer end of the pivot pin 194, and a retainer cap 193 is applied by means of screws 2%.
  • An O-ring-annular groove set-up 202 provides a seal against leakage.
  • FIGURES 1 and 4 The Wobble plate, interior construction Turning now to FIGURES 1 and 4, the wobble plate housing 162 will be observed to carry two outer races 2%. Between these units is provided a double-faced inner race 2&8. Bearing grade balls 2155 are carried on each side of the inner race and between the outer races 2%, using appropriate spacing apparatus as known in the ball bearing art or separators to provide an anti-friction mounting of the inner race 208 relative to the remainder of the wobble plate assembly.
  • the inner race 263 has a radially inwardly extending web 212 of annular configuration. This web extends into the previously described notch 158 of each piston 155. This also extends into the notch of each ball 169 retained within a pocket in the notch 158 of the piston. Thus, an operable relationship is established between the inner race 2% and the pistons via connection of the ball. It should be noted that there is a limited amount of movement between the ball and the web 212 because the inner race 20% rotates at the same r.p.rn. but not at uniformly equal speed with the pistons 155.
  • the ball will assume a slight oscillatory or elliptical motion relative to the web 212 and with prolonged opcration will gradually work its way around the inner periphery of the web in a slow, walking-type motion.
  • this relative movement is extremely limited and accordingly there is very little wear developed between the notch of the ball and the exterior faces of the inner periphery of the web 203.
  • the interior of the pump acts as a sump, automatic lubrication will be provided when pumping lubricating type oils as in the power steering application, one duty to which the pump is ap plicable.
  • FIGURE 4 the bottom sectioned portion of the balls 16% can be observed on the other side of the wobble plate web 212. Also, in this figure of the drawings, the other half of each piston is shown in dotted outline, and where the wobble plate web is completely broken away, the far half of the ball and the piston are shown in elevation, the ball being sectioned through the bottom portion bridging the notch.
  • FIGURES 6, 7 and 8 there is shown an important aspect of the present invention in the form of a movable, shock-absorbing segment separating the intake portion 106 of the annular passage 194 of FIGURE 3a from the outlet or exhaust portion Tilt; of such passage.
  • FIGURE 6 is a front elevation of one of the heads 54, 56 with a first embodiment of the separating segment mounted therein, and FIGURE 7 is a section taken through FIGURE 6 as indicated.
  • a movable segment in several different forms is provided to damp or modulate this chatter or vibration.
  • the segment of the first embodiment as shown in FIGURES 6 and 7, comprises a disc-like head 214- that has a fiat upper surface, ground or lapped exactly smootl with the plane of the remainder of the inner working face of the head.
  • this is conically tapered on the back edge and fits into a conically tapered opening 216 provided in the face of a pump head.
  • the two are lapped in for a close fit.
  • the lower portion of the segment head 214 spans the solid portion or land separating the intake from the exhaust.
  • FIGURE 8 which is an analogous systern but slightly different shaped head, accordingly designated 215, we can observe the interrelation of the parts making up the assembly. It will also be evident from FIGURE 8 that the recess 217 to accommodate the difference shaped head is of appropriate configuration for this purpose and lapped to a valve fit.
  • a stem 218 extends through a bore 220 of a web 222 on the back side of the recess 217 and coaxially of a stepped bore 224.
  • a retainer nut 226 is run onto a thread provided on rod 218.
  • a lock nut 228 holds the retainer nut 226 in position.
  • Retainer nut 226 is provided with a notch 230 to receive one end of a torsion spring 232 and the web 222 provided with a notch 234 to receive the other end of the spring 232.
  • FIGURE 6 note two stop pins 236 and 238 engageable with respective sides of a notch 240 of segment head 214 that spans the exhaust passage E.
  • the segment is movable between the solid and dotted line positions, the pins 236, 238 establishing such limits of movement.
  • On the intake side there is a notch 242 that works across the intake passage I.
  • the rotational movement of the head 214 may be on the order of only a few thousandths of an inch. However, little it may be, it will be effective to damp out the vibrations.
  • the notch 242 will simultaneously be moved between its solid line and dotted outline positions and that accordingly the area of the intake will be reduced. This will be effective to help lower the overall pressure, as will the expansion of exhaust side movement of the notch 240 to enlarge it.
  • FIGURE 9 Another form of the segment head is therefore illustrated in FIGURE 9 wherein instead of square notches as according to FIGURE 6, smooth, curvilinear notches are provided.
  • the notch 244 defines a deep loop, in the bight 246 of which is positioned a common l E limit pin 248. It will be noted that in the solid line position, the bight portion 246 contacts the left side of the pin and in the dotted line position, the right side. Thus, a single pin provides full limit of motion.
  • the notch 250 is also of curvilinear profile but of smaller size than the exhaust side. Relative area of each or the ratio of area is generally similar to that in FIGURE 6 but as mentioned can be tailored to particular applications.
  • An advantage of the pump of the present invention is that the circular type segment of FIGURES 6-9 can be changed to meet a particular application.
  • the area between the notches 244 and 259 in FIGURE 9 is greater than the diameter of a piston passing thereacross to provide a positive separation between exhaust and intake sides of the pump.
  • the third embodiment segment This is shown in FIGURE 10 and is of generally cylindrical configuration, but stepped, as distinguished from the head-stem structures of the two embodiments illus trated in FIGURES 6 through 9.
  • the cylindrical body portion is designated by the reference numeral 252 and the head portion 254, a step therebetween, by virtue of the fact that the disc-like head is of slightly larger diameter than the body 252.
  • the head is notched at 256 for the exhaust side and at 258 for the intake side.
  • FIG. 11 it. will be noted that a different and more simple attachment is provided than the relatively complicated structure shown in FIG- URE 8.
  • the head is merely floating in its appropriate cavity and is pressed therein by virtue of the oil pressure developed between the adjacent cylinder block and the top of the segment.
  • a notch 260 is provided in the head portion 254 to embrace a pin 262 mounted in the step of the recess of the pump head.
  • a spring 264- is positioned between the pin and one end of the notch and the other end of the notch embraces the other side of the pin.
  • the segment is biased in the arrow direction 266, tending to close the exhaust portion E and open the intake portion I by the appropriate notches provided. Pressure surges will cause the segment to rotate in the arrow 268 direction and provide the damping action previously referred to.
  • FIGURE 13 The reversible pump embodiment of FIGURE 13
  • opposed segments 270 are utilized so that a reversible pump action can be produced.
  • These segments are shown in very elementary form as having generally similar, or symmetrical square notches 272 formed therein to operate in the exhaust and inlet sides, in the same manner as previously described.
  • These units are mounted in the same manner as the embodiment of FIGURES 10 and 11, being held in place by pump pressure.
  • a two-way spring and pin relationship is provided.
  • a pin 274 is straddled by the notch 276 in each segment 270 and wafile spring 278 are provided on each side of the pin and between each end of the notch 276.
  • the segment is movable in both directions, as indicated by the double-ended arrow 279.
  • FIGURES 14 and 15 By reference to FIGURES 14 and 15, a one-Way pump segment is illustrated as comprising two concentric ringlike or annular units defining the opposed cross-over segments with one of the segments movable for vibration damping purposes. Since there is only one segment, the pump, therefore, is a one-way unit.
  • annular groove such as 104 in FIGURE 3a, defining the intake and outlet cavities in the pump head, is made slightly larger to accommodate the mechanism working therein, and is accordingly here designated by the reference numeral 289.
  • annular groove 2% Within this annular groove 2% are positioned two coperating concentric ring-like units to establish a fixed segment and an opposed movable segment.
  • the outer ring is designated 282 and as indicated is of ring-like structure with a cross-over segment portion 284 formed integrally therewith. This extends across the groove 2% and cooperates with the inner ring to form a seal between the intake 1 and the outlet segment E. It is noted that bores are provided tangentially through the wall of the unit to mate with the intake port 110 and the outlet port 112.
  • the outer ring 282 is suitably immobilized against rotary movement by being either press fitted into the annular groove 28% or locked with some kind of a pin or a pin-notch arrangement.
  • the inner ring is designated 286 and is fitted over the interior periphery of the annular groove 280 but is made rotatable and appropriate clearance is provided between its periphery and the segment portion 284 for rotation.
  • a notch 290 is provided in the cross-over segment portion 2&8 to straddle a pin 2% with a spring 294 positioned between the pin and the other side of the notch.
  • the spring is calibrated to the working pressure level where vibration is to be encountered. The effect of the spring as will be evident is to tend to rotate the inner segment in the arrow 2% direction, tending to maintain the exhaust segment or exhaust portion of the annular groove 280 at minimum volume.
  • Function of the device is as for the embodiments previously described in damping destructive vibration or providing servo-action or both.
  • the inner ring can be made stationary and the outer ring with its segment made to rotate by reversal of parts as will be evident to the skilled engineer.
  • the reversible unit of FIGURE 16 The annular groove is designated 280 because of the same size as the FIGURE 14 embodiment. However, the outer ring is designated 2% because machined with a sliding clearance to the exterior periphery of the groove 2%. This is provided with a cross-over segment designated 2% having a notch 30th therein straddling a pin 392. Springs 304 are placed on each side of the pin to resist movement of the segment in either direction toward the pin.
  • the inner segment is designated 286 because of substantially the same dimensions as that of FIGURE 14 being rotatable relative to the segment 2% and to the interior periphery of the annular groove 280. However, smaller and shorter springs 3%- are placed on each side of the pin to provide the dual bias just referred to relative to the segment 298.
  • the fifth embodiment segment 0 FIGURES 17 and 18 Often in the handling of fluids, suspended particulate material are encountered, despite the fact that the fluid is continuously filtered in an effort to remove such particles.
  • the life of the unit could be substantially enhanced using common materials such as brass and bronze as distinguished from sintered silicon carbide or other more expensive but highly durable materials.
  • FIGURE 17 We note the inlet and exhaust segments designated by I and E respectively. Communicating with the tail end of the exhaust segment is an oval slot or groove in plan as in FIGURE 17 designated 3%.
  • the segment is a generally cylindrical unit 3% but of stepped nature with a top disc surface 314) of a diameter the same as the width as the slot 306 to provide a seal, as indicated at the arrow points 312.
  • the purpose of the sleeve 316 is to provide rotation of the segment 3% to isolate it from rubbing friction with the spring 318. Between the bottom of the segment 308 and the bottom of cup 316 is interposed a wafile spring 320 to bias the segment toward a cylinder block or out of the cup.
  • the segment 3% can rotate in the arrow 322 direction to reduce the scrubbing wear or either to continuously uniformly lap the top surface of the segment resulting in an automatic smooth, sealing surface maintenance, thus prolonging the efiective life of the pump.
  • FIGURE 18 When FIGURE 18 is observed, it will be evident that the unit is capable of axial movement to pass solid particulate materials without damage by overcoming the bias of spring 326 positioned between the bottom of the segment 308 and the bottom of the cup 316.
  • segment is adapted to circumferential movement in both directions along the doubled headed arrow 328 direction to serve in its anti-vibration capacity as previously discussed.
  • FIGURES 19 and 20 It is of course to be understood that the embodiment as previously discussed in FIGURES l7 and 18 is a oneway pump. This can be modified in accordance with FIGURES l9 and 20 to provide a two-way pump, but in this case using a slightly less complex and truly cylindrical segment. Thus, the segment is designated by the reference numeral 330 and is carried in an oval cavity 332 for dual direction movement in the double-headed arrow 334 direction.
  • the seventh embodiment segment of FIGURES 21 and 22 In this embodiment a slidable but non-rotatable segment is utilizedand the entire unit is bolted into the annular pump head slot in a very eflicient manner.
  • the unit comprises a lower arcuate shaped carrier 338 having bolt bosses 340 at each end.
  • the left hand bolt boss supports a generally L-shaped spring retainer 342 having the leg thereof receiving bolt 344 and the arm upstanding to receive the left hand end of the spring 346.
  • the arm portion is hollowed out as a spring receiving cavity 348.
  • the movable segment is designated by the reference numeral 350 and is shown in plan of FIGURE 21 as of arcuate shape to follow the contour of the annular intake-exhaust groove, closely machined at the side to provide a sliding seal.
  • the left hand end is hollowed as at 352 to receive the right hand end of spring 346.
  • a lower lip portion 353 is formed to slide under a retainer 3535' held by the bolt 344 in the manner indicated.
  • This aspect of the invention is to encompass a unit which is axially movable against the bias of a spring or a cushion of hydraulic fluid, or in short, means biasing the segments in an axial manner toward a cylinder block.
  • FIGURES 23 and 24 A very good piston embodiment incorporating several unique features for adjustment and lubrication is illustrated in FIGURES 23 and 24.
  • the central body portion 354 is suitably manufactured from hex rod stock and is bored at 356 and threaded at each end as at 358.
  • Bronze ball seats 36%? are placed in the bore 356, the ball having been previously positioned as indicated at 362, dotted line. Thereafter, the cylinder ends 364 are threaded in to abut the ball seals 360 and proper clearance for movement of the ball is set.
  • the cylinder ends are threaded at 366 and lock with the threads 358, by a slight pitch difference so that once the ball clearance is established, the unit is automatically locked. Thereafter, the assembled unit can be chucked up and the cylinder surfaces 368 finish ground.
  • one of the fiat hex faces of the piston such as 376 rides on one of the faces of the 'septagonal separator spacer sleeve 144 previously described relative to FIGURES l and 4.
  • the second piston embodiment is shown in FIGURES 25 and 26 and is somewhat analogous in structure and positive lubrication characteristics to the first embodiment but is made of round stock with a flat on one side for antirotation.
  • tubular stock is used to produce the central body portion 378 having threads 380 at each end.
  • Cylindrical ball retainers 382 are utilized with spherical seat surfaces 384. These cradle the ball and, by virtue of the through bores 386, a positive l5 film of oil is provided to support the load and lubricate as previously discussed.
  • the third embodiment piston The piston embodiment of FIGURES 27 and 28 is applicable to production by the use of cast iron and a chilled ball technique. This involves suspending a chilled steel ball in a sand mold and pouring molten iron into the mold around the ball. The ball chills the iron next to the periphery giving a hard socket for ball-piston hearing wear and the remainder of the piston is ordinary soft cast iron, one of the best known piston materials for small hydraulic pumps.
  • the extended scope of invention relative to the cast iron piston would include the use of sintered metals with the ball in position during the sintering process. Inasmuch as the ball is of bearing grade steel, it will not be affected by the lower sintering temperatures.
  • This embodiment of the invention can also be made of injection molded nylon, reinforced Teflon, or the like, also utilizing a steel ball. These materials have inherent lubricity or lubrication characteristics and accordingly appropriate operation clearances will be developed in operation due to this feature.
  • the fourth embodiment piston As shown in FIGURE 29, a cast iron or steel piston W4 having integral central body and end piston portions is provided. This is then radially bored as at 496. T hereafter, an appropriate ball 4% is dropped in position and babbitt poured around it to provide a perfectly matched socket. The babbitt on cooling will provide proper work clearance.
  • this unit can utilize a bore 412, produced or cleaned up after the babbitt pouring operation to provide lubrication and mechanical support by a film of oil between the surface of the ball and the babbitt.
  • FIGURE 30 Another very practical piston for use in the present invention is shown in FIGURE 30. This utilizes stock hex rod material of tool steel grade.
  • the raw stock is provided with stepped and chamfered screw sockets 41d, threaded at the small diameter to receive fiat head screws 416 that hold the ball in an appropriate socket as illustrated.
  • the ball socket is provided by an appropriate straight bore with a spherical bottom actually cradling the lower half thereof.
  • the ball socket is designated by the reference numeral 418.
  • the end piston portions 422 are produced by suitable lathe and grinding operation.
  • annular grooves 424- are provided, for the purpose of catching dirt that may be entrained in the material being pumped; this prevents scoring of the cylindrical piston surfaces and the cylinder bores which of course as will be understood, in order to carry the loads imposed, are machined to very close tolerances relative to one another.
  • a wobble plate pump of adjustable stroke incorporating a variable spring load to cock the wobble plate and thereby establish working pressure. This is very simply changed by adjustment screw exposed on each end of the pump.
  • the scope of the invention includes a mechanically or hydraulically biased separating segment to automatically establish proper working contact or clearance between the cylinder blocks and the pump head.
  • the body of the pump is made of aluminum or other materials of appropriate expansion characteristic to provide a proper working clearance between the cylinder blocks and heads when the unit undergoes temperature changes such as heating under load.
  • the pistons are prevented from rotating by a novel separator segment which also can be hydraulically biased and split to respond to pressures which the pump is called upon to produce.
  • the heads of the pump are identical for minimum tooling costs.
  • cross-over tubes are provided and sealed in a very unique manner, together with coaxial through bolts giving further economies of manufacture and production and minimizing leakage openings.
  • an important advantage of the invention is the unique movable separator segment with its antivibration and servo-action characteristics. These are in several forms.
  • a further and important advantage of the invention resides in its adaptability to use a number of different kinds of pistons made in a very economical manner and Y of non-lubricating liquids, Teflon, Delrin, nylon, and other inherently lubricating synthetic resins, can be employed.
  • a hollow housing including a head with an interior working face
  • said means defining faces exposed to respective ones of said grooves
  • said limiting means limiting rotary movement of said first named means whereby said notches are retained in at least partially spanning relation to said grooves.
  • a hollow housing including a cylinder head with an internal Working face
  • a torsion spring having one end secured to said nut and the other end to said Web
  • said means defining notch-like faces exposed to respective ones of said grooves
  • a hollow housing including a head with an internal Working face, i
  • each of said means defining two spaced, notch-like faces exposed to respective ones of said grooves
  • stop means operable to limit movement of said first named means
  • a hollow housing including a cylinder head with an interior working face
  • stop means limiting said movement
  • said means defining said first land comprises a second ring member rotatable against one side in said groove with the first land movable therewith,
  • a cylinder containing block mounted to move the cylinder thereof in a manner successively traversing said inlet and exhaust grooves
  • a cylinder containing block mounted to move the cylinder thereof in a manner successively traversing said inlet and exhaust ports

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Description

Jan. 4, 1966 T. H. THOMPSON 3,
VARIABLE STROKE PUMP Filed June 4, 1963 8 Sheets-Sheet 1 732 L 4 iii- 5 75M H. THOMPISON 6v U/go/g .SETTLE Gen/a 1| Q :1 NVENTOR.
Jan. 4, 1966 T. H. THOMPSON 3,227,095
VARIABLE STROKE PUMP Filed June 4, 1963 8 Sheets-Sheet 2 Fza. Z
z Q 102 5 7;; a 4 7 lg. INVENTOR.
70 H. THOMPSON II I02 41/1. o/v 55771.5 & CRAIG F263 5 1 flrraKME/S Jan. 4, 1966 T. H. THOMPSON VARIABLE STROKE PUMP 8 Sheets-Sheet 5 Filed June 4, 1965 INVENTOR. 7 M H. THOMPSON BY M1. 50A; 52-7745 :2 ER/i6 ,47-roeA/EKs Jan. 4, 1966 "r. H. THOMPSON 3, 7,
VARIABLE STROKE PUMP Filed June 4, 1963 8 Sheets-Sheet 5 gig-ll Big-l5 INVENTOR.
Mao/14 50745 & [Aw/6 ATTORNEYS 1966 T. H. THOMPSON 3,
VARIABLE STROKE PUMP Filed June 4, 1963 8 Sheets-Sheet 6 //i A l INVENTOR. 70M hf 7Z/0MP50A/ W/zsa/m 77L 5 69 4/6 A T TOR'A/EVS Jan. 4, 1966 T. H. THOMPSO'I-NI 3,227,095
VARIABLE STROKE PUMP Filed June 4, 1963 8 Sheets-Sheet 8 INVENTOR. 70M H ZZ/OMPSOA/ BY mg 51 M15014 557745 & [24/6 AT -OA NE Ys United States Patent O 3,227,095 VARIABLE STRGKE PUMP Tom H. Thompson, Daytona Beach, Fla, assignor to Daytona Thompson Corporation, Daytona Beach, Fla, a corporation of Florida Filed June 4, 1983, Ser. No. 285,507 (Ilaims. (Cl. 103-162) This invention relates to variable stroke fluid handling mechanisms and more particularly to wobble plate pumps of improved construction and providing smooth operation at varying working pressures and capacities.
THE PRIOR PROBLEM Wobble plate type pumps and compressors are highly desirable structures in that they are capable of maintaining variable working pressures and variable capacities of volume throughputs. 'Dhe cant of the wobble plate establishes its capacity and if desired to stop pumping, it is merely erected to a zero pump position.
Pressure of the pump is controlled by the force with which the wobble plate is biased to its canted working position. This can be loaded with a calibrated spring or equivalent mechanism that has an established breakover point. Accordingly, automatically controlled working pressures are provided by the breakover point of the biasing means or mechanism employed.
However, pumps and compressors utilizing this principle of operation have suffered the following disadvantages:
(1) Water hammer.-This is a destructive vibration which is encountered as the mechanism rotates and liquid is delivered from the exhaust manifold during passage of the piston cylinder unit from the exhaust manifold across the separating segment to the intake manifold for further pickup of fluid.
(2) Foreign materiaL-Abrasive particles such as dust or the like in the fluid being pumped quickly destroy the necessary close working tolerances between the rotating cylinder block and the face of the fixed cylinder head with which it cooperates. This abrasion will result in disastrous pressure drops rendering the unit incapable of the task to which it was designed.
CONTRIBUTIONS TO THE ART A substantial contribution to the art would, therefore, be provided by novel fluid handling mechanism of a wobble plate type, capable of withstanding continuous duty and further characterized by built-in mechanism eliminating vibration and fluid hammer; and with other improved aspects of economy of manufacture and construction to provide long life and improved durability.
OBJECTS It is therefore an object of the present invention to provide a novel wobble plate pump.
A further object is to provide a wobble plate pump embodying several novel features of construction, improved simplicity and characterized by long life.
A further object is to provide a novel wobble plate pump embodying a unique separating segment between the inlet and exhaust manifolds that is so constructed to eliminate vibration as by fluid hammer.
A further object is to provide a wobble plate pump characterized by a unique piston guiding arrangement that renders the pistons non-rotatable.
A further object is to provide a novel wobble plate pump having a casing of controlled axial expansion to compensate for temperature changes within the unit and therefore maintain operating tolerances.
Other objects of this invention will appear in the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.
In the drawings:
FIGURE 1 is an axial section view of a pump of invention;
FIGURE 1a is a fragmentary section along line la-la of FIGURE 1;
FIGURE 1b is a fragmentary elevation view partly in section of an alternate embodiment of the spacer sleeve arrangement;
FIGURE 10 is a fragmentary section taken along the line 1cc of FIGURE 12:;
FIGURE 2 is a right end elevation view of FIGURE 1;
FIGURE 3 is a section view taken along the line 33 of FIGURE 1;
FIGURE 4 is a section view taken along the line 4--4 of FIGURE 1, but with the Wobble plate in the null or true transverse position as distinguished from FIGURE 1;
FIGURE 5 is a fragmentary elevation taken along the line 5-5 of FIGURE 4;
FIGURE 6 is an elevation view of a pump head as along the line 66 of FIGURE 1, showing details of a first embodiment separating segment in accordance with the invention;
FIGURE 7 is a section view taken along the line 7-7 of FIGURE 6;
FIGURE 8 is an enlarged fragmentary section view similar to FIGURE 7 but of the segment only to better show details;
FIGURE 9 is an enlarged fragmentary elevation similar to FIGURE 6, showing a second embodiment of separating segment;
FIGURE 10 is a perspective view of a third embodiment separating segment;
FIGURE 11 is a fragmentary section view showing the third embodiment separating segment of FIGURE 10 mounted in a pump end plate on head;
FIGURE 12 is a fragmentary elevation of the third embodiment segment mounted in a head, showing stop pin and calibrated control spring;
FIGURE 13 is a fragmentary elevation of the interior face of a head similar to FIGURE 6, but showing opposed segments providing a reversible pump;
FIGURE 14 is a fragmentary elevation view of a fourth embodiment segment mounted in a head and showing stop pin and calibrated control spring;
FIGURE 15 is a fragmentary section View taken along the line 15-15 of FIGURE 14-;
FIGURE 16 is a fragmentary elevation view of the interior face of a pump head similar to FIGURE 14, but showing that segment arrangement modified to provide a reversible pump structure;
FIGURE 17 is a fragmentary elevation view of a fifth embodiment segment mounted in a pump head;
FIGURE 18 is a section along line 18-18 of FIG- URE 17;
FIGURE 19 is a fragmentary elevation view of a sixth embodiment segment mounted in a pump head;
FIGURE 20 is a fragmentary section view taken along the line lit-20 of FIGURE 19;
FIGURE 21 is a fragmentary elevation view of a seventh embodiment segment mounted in a pump head and showing calibrated spring and stop, this view greatly enlarged;
FIGURE 22 is an elevation along the line 22-22 of FIGURE 21;
FIGURE 23 is an enlarged axial section of a first embodiment piston of invention;
FIGURE 24 is an elevation view taken along the line 2424 of FIGURE 23;
FIGURE 25 is an enlarged fragmentary axial section view of a second embodiment piston;
FIGURE 26 is an end elevation taken along the line 2626 of FIGURE 25;
FIGURE 27 is an enlarged axial section view of a third embodiment piston;
FIGURE 28 is an elevation view along the line 2828 of FIGURE 27;
FIGURE 29 is a side elevation, partly in section, of a fourth embodiment piston;
FIGURE 30 is a side elevation practically actual size, and partly in section, of a fifth embodiment piston; and
FIGURE 31 is an end elevational view of the piston assembly illustrated in FIGURE 30.
Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.
THE INVENTION The housing arrangement and right hand head By reference to FIGURES 1 and 3, it will be evident that the pump is designated by the reference numeral t) and axially is constructed as a housing 52 of square but annular shape as indicated in FIGURE 3. At each end, as best shown in FIGURE 1, there is a pump head. As viewed in FIGURE 1, the right hand head is designated 54 and the left hand head 56. It will be noted that the right hand head is provided with a stepped bore 58 and the left hand head with a stepped bore 6t? to receive antifriction bearings. A drive shaft 62 extends through the bores 58 and 60. In the bore 53, there is provided a ball bearing 64 in the larger diameter portion. It will also be noted that the shaft d2 is stepped as at 66 to be received in the bearing 64. A sleeve spacer 67 is inserted from the outside and is retained in place by an end cap 68, also shown in FIGURE 21 that is retained in place by bolts '79. It will be evident that the end cap 68 presses against the sleeve spacer 67 and thus retains the bearing 64 in proper position. An O-ring grooved system 72 seals the end plate 68 against leakage. A cap 74 is threaded into the right end of the shaft 62 and thus the shaft is held to the right end head 54 after initial assembly, to facilitate further assembly and attachment of r the left hand end mechanism.
The left hand head As previously mentioned, left hand head 56 is provided with a stepped bore 60 through which the shaft 62 is passed. Around the shaft, is positioned a roller bearing '76, heavier to withstand the radial forces imposed by a drive pulley 73 attached to the left most end of shaft 62.
To provide additional body an end cap 86 of generally circular configmration but heavier in axial thickness than the end cap 68 on the other end of the pump is provided. This is coaxially bored at 82 to receive the shaft 62 and the bore is stepped to receive a portion of the roller bearing '76 and the bearing retainer and seal 84 as indicated. Bolts 86 are passed through suitable bores in the end cap 80 and into the left end head 56 to provide the assembly. An O-ring groove system 87 is provided in the cap SIB to seal against leakage.
The drive pulley In order to reduce overall length, the drive pulley i8 is of arcuate section and includes a V-groove 88 in the periphery for connection to the V-belt, as of an automobile fan belt for power transmission purposes.
A unique feature is pointed out at this time relative to the manner in which the drive pulley is attached to the shaft 62. It is noted that a Woodruff key 9t fits into a groove of the pulley and an appropriate arcuate slot in the shaft 62. Note that the fiat edge of the key it is bored at 92 to receive the cylindrical end 94 of the attachment nut as, the latter suitably of the socket head type. Appropriate bore and counterbore as indicated threadably receives the nut 96.
It will be evident that when the cylindrical end 94 moves into the bore 92, a dual lock is provided as follows:
(a) Torsional: thus the pulley is locked relative rotatable movement on the shaft 62; and
(b) Axial: the pulley is locked against axial movement on the shaft 62.
The typical end plate porting efe-rring now to FIGURES l and 3, it will be noted that the end plates are provided with upper and lower horizontal cross bores 98 and 100. These are suitably produced by drilling operation followed by placement of plugs to seal the left end as indicated at 192.
Coaxially of the shaft 62, there is provided in the inside face of each head an annular groove 104, as will best be understood by reference to FIGURES 3 and 3a.
Relative to the groove 1%, it will. be understood that at the top and bottom it is plugged or otherwise suitably provided with a separating segment or land, several embodiments of which will be described hereinafter, thus providing an intake side 1% and an exhaust side 108, FIGURE 3.
A vertically disposed bore is drilled from the top edge downwardly to intersect the intake portion 106, and an exhaust bore, also of vertical configuration and designated 112, extends from the bottom edge up to intersect the exhaust segment 108 of the groove 104. After the borings are made, they are suitably capped, as indicated by reference numerals 102.
A word at this point to clarify FIGURE 1. The annular groove 104 has not been shown in FIGURE 1, because the section was taken through what would be a separating segment and thus would be solid metal as indicated.
A further word at this point. It will be evident that a cylinder rotor is superimposed upon the head in the view of FIGURE 3, and the annular groove 16114 is therefore beneath in dotted outline.
In further discussion, typified by that of FIGURE 6, the bare face of the end plate will be illustrated to provide full clarity of all aspects of the separating segments of invention.
The cross-over connection tubes If We now visualize that the heads are identical, we can understand the manner in which intake to each of the heads can be provided through a common opening as the opening 114 shown in FIGURE 2. Also, common outlet can be provided as by the opening 116 of FIGURE 2.
Now referring back to FIGURE 1, we observe that two inlet cross-over tubes 118 extend between the right and left hand heads 54, 56, and two lower cross-over tubes 120 are similarly disposed at the bottom of the unit, functioning as outlet cross-over tubes as will be hereinafter apparent.
As shown at the upper left hand corner of FIGURE 1, the end of a cross-over tube fits into a stepped bore 122 that will be understood, of course, to intersect, by reference to FIGURE 3, the cross bore 98.
At the bottom, similar holes are provided, designated 123, to receive the ends of the lower cross-over tubes 120.
Back to the upper left hand corner of FIGURE 1 again, note that the end of the cross-over tube 118 is stepped at 124 to provide a seat for an O-ring 126. The O-ring is thus retained between the step 124 and the upper step of the bore 122.
The unit is retained together axially or longitudinally by through bolts 128 having nuts 130 on the left end thereof. Note the heads of the bolts in FIGURE 2. It should be noted at this point that full pressure of the bolts is not taken by the O-rings 126. Instead, the ends of the housing 52, designated 53, receives the full bolt thrust. Thus, the O-rings 126 are not extruded and, accordingly, an effective seal is provided. It will be noted that leakage from the sump defined by the interior of the housing is prevented by an O-ring groove system 132 formed in the face of each end 53. Thus, when the bolts 128 are drawn up tight, the cross-over tubes 118 and 120, and the housing and each head are effectively sealed. It will be evident that the substantial convenience of economy of manufacture and assembly is provided in accordance with the use of the cross-over tube structure.
To review briefly at this point, keep in mind that the heads 54 and 56 are identical, and thus when placed faceto-face, the top cross-over tube system serves as intake and the bottom cross-over tube system serves as exhaust. Of course, when the pump is reversed, the reverse is true.
The wobble plate and piston. system, general set-up Turning now to the actual functioning interior parts of the unit, it will be observed that right and left cylinder rotors or blocks 13d and 136 are fitted upon the shaft 62. In the embodiment of FIGURE 1, these are suitably locked in place on the shaft to establish an overall dimension somewhat less than the distance between the interior faces of the right and left hand heads. This provides running clearance.
To view the cylinder rotor in plan, refer to FIGURE 3 and note that it is of circular shape, beveled as at 138 to provide clearance for the Wobble plate 140.
The manner in which the rotors 134, 136 are staked or fastened to shaft 62 is illustrated at the left side of FIG- URE 1, wherein a Woodrulf key 90 cooperates with an appropriate slot in the shaft 62 and a groove in a bore of rotor 135. The bore is designated by the reference numeral 141, FIGURE 1.
By reference to FIGURES 1 and 3, it will be noted that each cylinder rotor or block 134, 136 is provided with seven circumferentially spaced cylinder bores 142. These receive the respective ends of double-ended pistons to be later described in several embodiments.
T he septagolml spacer sleeve Continuing to refer to FIGURES 1 and 3, it will be noted that a septagonal spacer sleeve 144 extends between the innner faces of the blocks 134, 135. The seven faces of the septagonal spacer sleeve designated 146 cooperate with flats on the cylinders to prevent rotation thereof. In FIGURE 3, a section view of the spacer sleeve 146 is provided, showing the seven sides.
Referring to the right side of FIGURE 1, we note that the terminal end of the spacer sleeve 144, and also in FIGURE la, is provided with a plurality of radially extending notches 143 to release high pressure fluid that crawls along the shaft 62 from between the heads 54, 56 and rotor faces and releases this high pressure leakage to the sump.
It will be noted that the spacer sleeve 144 is not necessarily locked to the shaft because it will be retained against the rotation relative thereto by the fact that the flats of the piston are against it and these cannot move, because the blocks 134, 136 are locked to the shaft by means of the keys 90, illustrated at the left side in FIG- URE 1.
At this point, it should be noted that the keys 90 by which the rotors 134, 136 are rotationally locked to the shaft 62 do not prevent axial movement. Also by virtue of the release notches 148, the pressure developed between the right and left hand heads and the right and left hand blocks will be effective to press the blocks tight against the ends of the spacer sleeve. This is effective to provide an automatic overall dimension at the exterior 6 faces of the blocks to cooperate with the dimension established between the right and left hand heads and the ends of the housing 52.
Further, the housing is of aluminum for expansion when the pump heats up under load. This automatically moves the heads out to provide proper clearance with the cylinder blocks, preventing galling and scrubbing and yet maintains the close clearances.
Typically, operating at pressures of 1000 pounds, it will be understood that the clearances must be very close, on the order of one ten thousandths of an inch in the present pump.
Accordingly, a typical dimension between the inner faces of right and left hand heads will be about two ten thousandths of an inch greater than the dimension between the exterior faces of the right and left hand blocks when pressed tightly against the ends of the spacer sleeve. As pointed out before, the key does not prevent the block 136 from axial movement on shaft 62. Since the septagonal spacer sleeve 144 is also not locked against axial movement, the unit rotor 136, spacer 144, rotor 134, automatically is centered between the heads providing one ten thousandth of an inch clearance at each end.
Also, the fact that the high pressure leakage is bled off through the notches 148, the rotors are not pressed against the heads, and thus no galling or scoring of the rotors running dry against the heads will be encountered as during pump startup.
Of course, in the present application of this pump, hydraulic fluid is being pumped and automatic lubrication is thereby provided.
Alternate embodiment of spacer sleeve Referring to FIGURES 1b and 10, there is illustrated an alternate embodiment spacer sleeve whereby the sleeve is split and a biasing spring is interposed to force the rotors into close relation with the inner faces of the right and left hand heads 54, 56.
In this embodiment, the two halves of the spacer sleeve are designated by the reference numeral 150 and at the ends abut the inner faces of the blocks 13 4, 136 as previously indicated. Spring 152 is interposed between the two halves 150 and thus biases the halves against the blocks and the blocks in turn toward the respective pump heads.
As shown in the lower right hand corner of FIGURE lb, and in FIGURE 1c, index pins 154 received half and half by a sleeve half 150 and a cylinder rotor 134, 136, provides proper orientation of the bearing surfaces or flats of the separator sleeve halves with flats of the pistons to prevent anti-rotation.
As regards this embodiment of the invention, it is to be understood that the spring 152 can be omitted and the two halves 159 made longer so that they abut at a joint at the middle. Additionally, the release notches 148 can be omitted at each end or reduced in size, so that the high pressure will bleed partially between the spacer and the cylinder blocks and partially through the joint at the center of the split separator segment. This will hydraulically bias the cylinder blocks toward the pump heads and will be effective as the pressure increases to automatically press the blocks more firmly toward the heads and thus retain the increased pressure.
It will be evident in contrast that the system using the spring 152, as shown in FIGURE lb, will provide only a fixed amount of bias, thus when the pressure of the pump reaches a certain level, the bias will not be helpful to sustain higher pump pressures. This, of course, provides an automatic working level by virtue of the calibration of the spring 152 and, as will be understood, either system has its advantages and provides flexibility in the overall application of the pump.
The piston Referring to FIGURES l and 4, it will be noted that the pistons 155 are suitably made from hexagon rod stock and are turned and ground at the ends to provide a highly accurate mate for the previously mentioned bores 142. The piston ends are designated by the reference numeral I56.
By using hex stock, referring to FIGURE 4, it will be noted that one of the fiat sides is in abutting, sliding relation with one of the sides 148 of the spacer sleeve 144. This automatically provides anti-rotation of the piston to prevent its ball notch from contacting the rotor of the wobble plate improperly, as will become apparent hereinafter.
Referring to FIGURE 1 again, note that the piston is provided with a generally U-shaped notch 158 to receive a slotted ball 160.
The particular configuration of the various pistons utilized in the invention and the manner in which the balls are retained in place will be discussed later relative to the various embodiments thereof.
The wobble plate and its mounting Continuing to refer to FIGURES 1 and 4, and additionally to FIGURE 5, we note that the wobble plate shell comprises two mirror image halves designated by the reference numeral 162, FIGURE 5.
As shown in the bottom portion of this figure, these halves 162 have mating annular walls 164, provided with mating bores 166 to receive recessed head through bolts 168 for attachment. The radial walls 170 of the halves 162 are each provided with openings 172 to accommodate the pistonbiock, etc., assembly and shaft 62.
On opposite sides, the halves 162 are provided with semi-circular mounting segments 174 attached by weld 176, FIGURE 5. These do not produce a full circle and thereby leave a notch 178 to receive a control spring assembly. Spaced 90 from the notch 178, there is a bore 180 to receive a retainer pin 182. This will be evident in both FIGURES and 4. These hold the biasing springs in the notches 178.
The biasing or control spring mechanism is of two parts and includes a back-up bar 184 lying along one side of the notch 178 and a scroll-like control spring 186 cradled along the other side of the notch.
Referring now to FIGURE 4, note that the vertical walls 138 of the body 52 are bored at 190 to receive pin bushings 192. Each pin bushing 192 receives a pivot pin 194 that is notched on the inner end to straddle the retainer pin 182, the back-up bar 184- and scroll spring 186. The inner end of the bushing of course fits into the circular opening provided by the two semi-circular mounting segments 174-, see FIGURE 5.
The pivot pin 194 bottoms the side or periphery of the halves 162 and thus does not cramp either the retainer pin 182 or the bar 184, scroll spring 186 assembly. The outer end of the pivot pin provides an effective pivot within the pin bushing 192.
A disc-like bush cap 196 fits against the outer end of the pivot pin 194, and a retainer cap 193 is applied by means of screws 2%. An O-ring-annular groove set-up 202 provides a seal against leakage.
Referring back to FIGURE 5, note the screws 204 that are adjustable against the scroll spring 186. Looking at FIGURE 2, these are noted as extending through the right and left heads 54, 56 for support. These control the working pressure of the pump, and it will be evident that asthe screws are tightened inwardly, the pressure on the spring 186 is increased. This provides a greater resistance for the wobble plate to erect itself to a no-pump position and thus stop pumping when a predetermined or preadjusted pressure level is reached.
From the foregoing, it will be obvious that this embodiment or type of pump automatically provides a fixed upper limit working pressure, dependent upon the requirements of the application. Other types could control by different reactions.
g The Wobble plate, interior construction Turning now to FIGURES 1 and 4, the wobble plate housing 162 will be observed to carry two outer races 2%. Between these units is provided a double-faced inner race 2&8. Bearing grade balls 2155 are carried on each side of the inner race and between the outer races 2%, using appropriate spacing apparatus as known in the ball bearing art or separators to provide an anti-friction mounting of the inner race 208 relative to the remainder of the wobble plate assembly.
It will be noted that the inner race 263 has a radially inwardly extending web 212 of annular configuration. This web extends into the previously described notch 158 of each piston 155. This also extends into the notch of each ball 169 retained within a pocket in the notch 158 of the piston. Thus, an operable relationship is established between the inner race 2% and the pistons via connection of the ball. It should be noted that there is a limited amount of movement between the ball and the web 212 because the inner race 20% rotates at the same r.p.rn. but not at uniformly equal speed with the pistons 155.
Actually, the ball will assume a slight oscillatory or elliptical motion relative to the web 212 and with prolonged opcration will gradually work its way around the inner periphery of the web in a slow, walking-type motion. However, it is evident that this relative movement is extremely limited and accordingly there is very little wear developed between the notch of the ball and the exterior faces of the inner periphery of the web 203. Further, it will be noted that since the interior of the pump acts as a sump, automatic lubrication will be provided when pumping lubricating type oils as in the power steering application, one duty to which the pump is ap plicable.
In FIGURE 4, the bottom sectioned portion of the balls 16% can be observed on the other side of the wobble plate web 212. Also, in this figure of the drawings, the other half of each piston is shown in dotted outline, and where the wobble plate web is completely broken away, the far half of the ball and the piston are shown in elevation, the ball being sectioned through the bottom portion bridging the notch.
THE SEGMENT OF INVEWTION Segment embodiment I Referring to FIGURES 6, 7 and 8, there is shown an important aspect of the present invention in the form of a movable, shock-absorbing segment separating the intake portion 106 of the annular passage 194 of FIGURE 3a from the outlet or exhaust portion Tilt; of such passage.
FIGURE 6 is a front elevation of one of the heads 54, 56 with a first embodiment of the separating segment mounted therein, and FIGURE 7 is a section taken through FIGURE 6 as indicated.
As pointed out in the earlier portion of this description, when the pump is working close to its established pressure level, and a fluctuation develops of a vibratory nature, the ensuing vibration can result in damage and destruction to the pump.
In accordance with the invention, a movable segment in several different forms is provided to damp or modulate this chatter or vibration.
The segment of the first embodiment, as shown in FIGURES 6 and 7, comprises a disc-like head 214- that has a fiat upper surface, ground or lapped exactly smootl with the plane of the remainder of the inner working face of the head.
As shown in the section view of FIGURE 7, this is conically tapered on the back edge and fits into a conically tapered opening 216 provided in the face of a pump head. The two are lapped in for a close fit. It will be noted from FIGURE 6 that the lower portion of the segment head 214 spans the solid portion or land separating the intake from the exhaust.
By referring to FIGURE 8 which is an analogous systern but slightly different shaped head, accordingly designated 215, we can observe the interrelation of the parts making up the assembly. It will also be evident from FIGURE 8 that the recess 217 to accommodate the difference shaped head is of appropriate configuration for this purpose and lapped to a valve fit.
A stem 218 extends through a bore 220 of a web 222 on the back side of the recess 217 and coaxially of a stepped bore 224. At the other end, a retainer nut 226 is run onto a thread provided on rod 218. A lock nut 228 holds the retainer nut 226 in position. Retainer nut 226 is provided with a notch 230 to receive one end of a torsion spring 232 and the web 222 provided with a notch 234 to receive the other end of the spring 232.
It will be evident from this construction that the spring provides two functions as follows:
(1) Hlding.-The tighter the spring 232 is wound, the more tightly the segment head 215 is forced into recess 217.
(2) Increased torsion resistance.--The tighter spring 232 is wound, the greater its resistance to turning away from an appropriate stop.
Referring now to FIGURE 6, note two stop pins 236 and 238 engageable with respective sides of a notch 240 of segment head 214 that spans the exhaust passage E. The segment is movable between the solid and dotted line positions, the pins 236, 238 establishing such limits of movement. On the intake side, there is a notch 242 that works across the intake passage I.
Function of this embodiment Visualize that the pump is turning in the arrow 244 direction. As each piston passes the notch 242, it is moving away from the surface of the paper towards the eye of the observer, intaking or pulling in fluid through the intake chamber I. As it .passes the bottom segment, the piston will change direction and move back from the eye of the observer toward the surface of the paper compressing the fiuid and forcing it out through the exhaust passage E.
Presume now that the working level of, for example 1000 pounds per square inch pressure, is just being approached by the work load imposed upon the pump. The fluid in the system for some reaosn begins to vibrate and hammer. The vibration will be effective to produce small pulses of a very dynamic nature, the type of a sharp hammer blow which will otherwise be extremely destructive at this high pressure. To even out or damp such vibratory knocks, the pressure pulses will move the head 214 between the solid and toward the dotted outline positions to cushion the shock and thus prevent damage.
It is to be understood, of course, that the rotational movement of the head 214 may be on the order of only a few thousandths of an inch. However, little it may be, it will be effective to damp out the vibrations.
Looking now at the intake side, note that the notch 242 will simultaneously be moved between its solid line and dotted outline positions and that accordingly the area of the intake will be reduced. This will be effective to help lower the overall pressure, as will the expansion of exhaust side movement of the notch 240 to enlarge it.
The second embodiment Depending upon the application of the pump, it will probably be required to tailor make the segment. Another form of the segment head is therefore illustrated in FIGURE 9 wherein instead of square notches as according to FIGURE 6, smooth, curvilinear notches are provided.
On the exhauts side E, the notch 244 defines a deep loop, in the bight 246 of which is positioned a common l E limit pin 248. It will be noted that in the solid line position, the bight portion 246 contacts the left side of the pin and in the dotted line position, the right side. Thus, a single pin provides full limit of motion.
On the intake side, the notch 250 is also of curvilinear profile but of smaller size than the exhaust side. Relative area of each or the ratio of area is generally similar to that in FIGURE 6 but as mentioned can be tailored to particular applications.
An advantage of the pump of the present invention is that the circular type segment of FIGURES 6-9 can be changed to meet a particular application.
It should be noted that the area between the notches 244 and 259 in FIGURE 9 is greater than the diameter of a piston passing thereacross to provide a positive separation between exhaust and intake sides of the pump.
The third embodiment segment This is shown in FIGURE 10 and is of generally cylindrical configuration, but stepped, as distinguished from the head-stem structures of the two embodiments illus trated in FIGURES 6 through 9.
Referring to FIGURE 10, it will be noted that the cylindrical body portion is designated by the reference numeral 252 and the head portion 254, a step therebetween, by virtue of the fact that the disc-like head is of slightly larger diameter than the body 252. The head is notched at 256 for the exhaust side and at 258 for the intake side.
The function of the notches is analogous to that of the prior embodiments.
However, by reference to FIGURE 11, it. will be noted that a different and more simple attachment is provided than the relatively complicated structure shown in FIG- URE 8. In this embodiment, the head is merely floating in its appropriate cavity and is pressed therein by virtue of the oil pressure developed between the adjacent cylinder block and the top of the segment.
Because of the film of oil between the two, however, it will be evident that there is no rubbing contact and thus no galling of the surfaces.
Referring now to FIGURE 12, the spring loading of the segment can be observed. A notch 260 is provided in the head portion 254 to embrace a pin 262 mounted in the step of the recess of the pump head.
A spring 264- is positioned between the pin and one end of the notch and the other end of the notch embraces the other side of the pin. Thus, the segment is biased in the arrow direction 266, tending to close the exhaust portion E and open the intake portion I by the appropriate notches provided. Pressure surges will cause the segment to rotate in the arrow 268 direction and provide the damping action previously referred to.
The reversible pump embodiment of FIGURE 13 As shown in this figure of the drawings, opposed segments 270 are utilized so that a reversible pump action can be produced. These segments are shown in very elementary form as having generally similar, or symmetrical square notches 272 formed therein to operate in the exhaust and inlet sides, in the same manner as previously described. These units are mounted in the same manner as the embodiment of FIGURES 10 and 11, being held in place by pump pressure. However, a two-way spring and pin relationship is provided. Thus, a pin 274 is straddled by the notch 276 in each segment 270 and wafile spring 278 are provided on each side of the pin and between each end of the notch 276. Thus, the segment is movable in both directions, as indicated by the double-ended arrow 279.
t should be pointed out relative to the embodiments of FIGURES 69 that the resistance to movement of the segment is adjustable by tightening the nuts 228, 226. However, in the embodiments similar to that of FIG- URES 1012, a calibrated spring is employed and produces only one resistance against movement. To change the resistance, of course, a spring of different calibration can readily be inserted because of the open cavity nature and exposed nature of the spring when a pump head is removed.
Operation of the embodiment of FIGURE 13 A rather subtle improvement of highly refined nature is evident from an observation of the embodiment of FIGURE 13. Thus, when the pressure increases in the exhaust side, the segments will both be cocked toward the inlet side, thus enlarging the exhaust cavity and simultaneously reducing the inlet cavity. This can be an assist in providing servo-action in any of several types of action.
This is effective during either direction of rotation of the pump because the segments 270 are symmetrical as previously pointed out.
The fourth embodiment segment of FIGURES 14 and 15 By reference to FIGURES 14 and 15, a one-Way pump segment is illustrated as comprising two concentric ringlike or annular units defining the opposed cross-over segments with one of the segments movable for vibration damping purposes. Since there is only one segment, the pump, therefore, is a one-way unit.
As shown in FIGURES 14 and 15, the annular groove such as 104 in FIGURE 3a, defining the intake and outlet cavities in the pump head, is made slightly larger to accommodate the mechanism working therein, and is accordingly here designated by the reference numeral 289.
Within this annular groove 2% are positioned two coperating concentric ring-like units to establish a fixed segment and an opposed movable segment. The outer ring is designated 282 and as indicated is of ring-like structure with a cross-over segment portion 284 formed integrally therewith. This extends across the groove 2% and cooperates with the inner ring to form a seal between the intake 1 and the outlet segment E. It is noted that bores are provided tangentially through the wall of the unit to mate with the intake port 110 and the outlet port 112.
The outer ring 282 is suitably immobilized against rotary movement by being either press fitted into the annular groove 28% or locked with some kind of a pin or a pin-notch arrangement.
The inner ring is designated 286 and is fitted over the interior periphery of the annular groove 280 but is made rotatable and appropriate clearance is provided between its periphery and the segment portion 284 for rotation.
Additionally, there is sufficient clearance between the outer periphery of the segment portion 288 thereof and the interior of the ring 282 to accommodate relative rotation. It is to be noted that a notch 290 is provided in the cross-over segment portion 2&8 to straddle a pin 2% with a spring 294 positioned between the pin and the other side of the notch. The spring is calibrated to the working pressure level where vibration is to be encountered. The effect of the spring as will be evident is to tend to rotate the inner segment in the arrow 2% direction, tending to maintain the exhaust segment or exhaust portion of the annular groove 280 at minimum volume.
Function of the device is as for the embodiments previously described in damping destructive vibration or providing servo-action or both.
Relative to the foregoing embodiment, it will be evident that the inner ring can be made stationary and the outer ring with its segment made to rotate by reversal of parts as will be evident to the skilled engineer.
The reversible unit of FIGURE 16 The annular groove is designated 280 because of the same size as the FIGURE 14 embodiment. However, the outer ring is designated 2% because machined with a sliding clearance to the exterior periphery of the groove 2%. This is provided with a cross-over segment designated 2% having a notch 30th therein straddling a pin 392. Springs 304 are placed on each side of the pin to resist movement of the segment in either direction toward the pin.
The inner segment is designated 286 because of substantially the same dimensions as that of FIGURE 14 being rotatable relative to the segment 2% and to the interior periphery of the annular groove 280. However, smaller and shorter springs 3%- are placed on each side of the pin to provide the dual bias just referred to relative to the segment 298.
Operation of this embodiment is as in FIGURE 13. Thus, excess pressure in the exhaust side E will cock both the cross-over segments 288 and 298 toward the intake side, thus enlarging the exhaust cavity and simultaneously reducing the inlet cavity. Calibrated springs, of course, are used and these are set to overcome the vibration problems which will be encountered in the operation of the pump for particular application.
The fifth embodiment segment 0 FIGURES 17 and 18 Often in the handling of fluids, suspended particulate material are encountered, despite the fact that the fluid is continuously filtered in an effort to remove such particles.
It will be evident that due to the close clearances of the present pump, transfer of such particles across the segment will be effective to score and Wear the same Very slightly. It would therefore provide a substantial advance in the art if the segment were not only circumferentially movable to damp vibration, but also axially movable to yield and permit passage of particulate materials to prolong the face life and profile and close running clearance of the unit.
Additionally, if the face of the separating segment could be rotatable and thus give or yield with the passage of the cylinder rotors thereover, the life of the unit could be substantially enhanced using common materials such as brass and bronze as distinguished from sintered silicon carbide or other more expensive but highly durable materials.
With this brief analysis of the problem, it will be evident from the following description that substantial durability as well as improved performance can be engineered into a pump in accordance with the concept of the present invention.
Turning now to FIGURE 17, We note the inlet and exhaust segments designated by I and E respectively. Communicating with the tail end of the exhaust segment is an oval slot or groove in plan as in FIGURE 17 designated 3%. The segment is a generally cylindrical unit 3% but of stepped nature with a top disc surface 314) of a diameter the same as the width as the slot 306 to provide a seal, as indicated at the arrow points 312.
The bottom cylindrical portion as shown in FTGURE 18 and designated 314, rides or rotates within a sleeve cup 315 which is abutted by a spring 318 biasing the unit toward the right as viewed in FIGURE 17.
The purpose of the sleeve 316 is to provide rotation of the segment 3% to isolate it from rubbing friction with the spring 318. Between the bottom of the segment 308 and the bottom of cup 316 is interposed a wafile spring 320 to bias the segment toward a cylinder block or out of the cup.
In actual operation, of course, it is to be understood that the pressure on the exhaust side will produce a film of oil between the segment and the cylinder rotor preventing rubbing friction.
From the foregoing, it will be evident that the segment 3% can rotate in the arrow 322 direction to reduce the scrubbing wear or either to continuously uniformly lap the top surface of the segment resulting in an automatic smooth, sealing surface maintenance, thus prolonging the efiective life of the pump.
The manner of rotation in the arrow 322 direction will become more evident when it is understood that the dotted circles 324 represent the piston path along the lower half of the segment, imparting slow rotation thereto.
When FIGURE 18 is observed, it will be evident that the unit is capable of axial movement to pass solid particulate materials without damage by overcoming the bias of spring 326 positioned between the bottom of the segment 308 and the bottom of the cup 316.
Referring again to FIGURE 17, it will be noted that the segment is adapted to circumferential movement in both directions along the doubled headed arrow 328 direction to serve in its anti-vibration capacity as previously discussed.
The sixth embodiment segment of FIGURES 19 and 20 It is of course to be understood that the embodiment as previously discussed in FIGURES l7 and 18 is a oneway pump. This can be modified in accordance with FIGURES l9 and 20 to provide a two-way pump, but in this case using a slightly less complex and truly cylindrical segment. Thus, the segment is designated by the reference numeral 330 and is carried in an oval cavity 332 for dual direction movement in the double-headed arrow 334 direction.
The reason why in this embodiment the segment must be truly cylindrical is to provide positive cut-off between the intake side and the exhaust side as the cavity 332 bridges them. As shown in FIGURE 18, if the land between the spring 318 and the intake side were not present, there could be fluid flow across the unit, passing through the gap between the lip 310 and the bottom cup 316. In FIGURE 20, it will be noted that a seal is thus provided between the intake and the exhaust segments.
It is to be understood, of course, that relative to FIG- URES 19 and 20, opposed segments will be employed to provide a two-way pump. r In summation, relative to the two embodiments shown in FIGURES 17 through 20, it is to be understood that by proper design, a segment that is biased toward the top of its retaining cavity and according toward the asso ciated cylinder block can be effected by hydraulic means. Thus, the meant the bottom of the unit would be greater than the area of the top of the unit and a bleed port provided for hydraulic fluid from the exhaust side to bleed under the unit and force it outwardly of its cavity.
Such embodiment is to be included within the scope of invention.
Further, relative to the embodiment of FIGURES l9 and 20, rotation in both directions in accordance with the double headed arrow 336 is accommodated and the dual movements in accordance with the arrow 336 is accomplished through opposing springs 337.
The seventh embodiment segment of FIGURES 21 and 22 In this embodiment a slidable but non-rotatable segment is utilizedand the entire unit is bolted into the annular pump head slot in a very eflicient manner.
As best shown in FIGURE 22, the unit comprises a lower arcuate shaped carrier 338 having bolt bosses 340 at each end. The left hand bolt boss supports a generally L-shaped spring retainer 342 having the leg thereof receiving bolt 344 and the arm upstanding to receive the left hand end of the spring 346. The arm portion is hollowed out as a spring receiving cavity 348.
The movable segment is designated by the reference numeral 350 and is shown in plan of FIGURE 21 as of arcuate shape to follow the contour of the annular intake-exhaust groove, closely machined at the side to provide a sliding seal. The left hand end is hollowed as at 352 to receive the right hand end of spring 346. At the right end a lower lip portion 353 is formed to slide under a retainer 3535' held by the bolt 344 in the manner indicated.
It will be evident that pressure on the exhaust side E will be effective to bias the segment 350, overriding the spring 346 as necessary to damp the vibrations.
Summary of the segments of invention In "iew of the foregoing, it is to be understood that an important advance in anti-vibration and servo-action wobble plate biasing devices for wobble plate pumps has been provided in accordance with the present invention and having the following characteristics:
(1) Arcuately movable to accommodate pressure surges in the exhaust side and resiliently cushion such surges to damp out destructive vibrations;
(2) Rotatable to reduce wear and prolong the life of the unit;
(3) Axially movable to accommodate the passage of solid particulate materials of an abrasive nature, thus prolonging the life of the unit;
(4-) Induce servo-action in either direction for biasing Wobble plate.
This aspect of the invention is to encompass a unit which is axially movable against the bias of a spring or a cushion of hydraulic fluid, or in short, means biasing the segments in an axial manner toward a cylinder block.
THE VARIOUS PISTON EMBODIMENTS OF INVENTION The first piston embodiment of FIGURES 23 and 24 A very good piston embodiment incorporating several unique features for adjustment and lubrication is illustrated in FIGURES 23 and 24.
In this unit, the central body portion 354 is suitably manufactured from hex rod stock and is bored at 356 and threaded at each end as at 358. Bronze ball seats 36%? are placed in the bore 356, the ball having been previously positioned as indicated at 362, dotted line. Thereafter, the cylinder ends 364 are threaded in to abut the ball seals 360 and proper clearance for movement of the ball is set.
The cylinder ends are threaded at 366 and lock with the threads 358, by a slight pitch difference so that once the ball clearance is established, the unit is automatically locked. Thereafter, the assembled unit can be chucked up and the cylinder surfaces 368 finish ground.
It will be noted that the cylinder ends are bored at 376). Further noting that the exposed end 372 of the cylinder end 364 is of smaller surface area than the spherical surface 374 of the ball seat, automatic lubrication is provided as follows:
Higher pressures are developed against the face 372, forcing fluid down the bore 370 and between the ball and the spherical seat 374. The ball thus rides on a film of oil at all times. Also, the mechanical load is carried on the film of oil being pumped. A load carrying cushion and automatic lubrication in a positive manner are therefore provided.
As shown in FIGURE 24, one of the fiat hex faces of the piston such as 376 rides on one of the faces of the 'septagonal separator spacer sleeve 144 previously described relative to FIGURES l and 4.
The second piston embodiment The second embodiment is shown in FIGURES 25 and 26 and is somewhat analogous in structure and positive lubrication characteristics to the first embodiment but is made of round stock with a flat on one side for antirotation.
Thus, as shown in FIGURE 25, tubular stock is used to produce the central body portion 378 having threads 380 at each end. Cylindrical ball retainers 382 are utilized with spherical seat surfaces 384. These cradle the ball and, by virtue of the through bores 386, a positive l5 film of oil is provided to support the load and lubricate as previously discussed.
After the unit is assembled, using round rod stock, a flat 3853 is milled as indicated in FIGURE 26 and the unit then chucked and the cylinder surfaces 3% ground and lapped to finish dimension. The thread set-up 3%, 3%, provides a lock system as discussed relative to FIGURE 23.
The third embodiment piston The piston embodiment of FIGURES 27 and 28 is applicable to production by the use of cast iron and a chilled ball technique. This involves suspending a chilled steel ball in a sand mold and pouring molten iron into the mold around the ball. The ball chills the iron next to the periphery giving a hard socket for ball-piston hearing wear and the remainder of the piston is ordinary soft cast iron, one of the best known piston materials for small hydraulic pumps.
By this technique, the iron, as it cools, shrinks away from the ball giving appropriate clearance for operation. This casting is efiective to produce the entire piston as designated 394 in FIGURE 27 with a central body portion 3% and piston end portions 3%. Lubrication and load support is effected by means of a through bore 4%. 0f course, after the piston is cast and properly cooled and aged, the piston end portions are finish ground and lapped as necessary to proper dimension. This embodiment is suitably shown as having an arcuate type flat 4&2 to accommodate the periphery of a truly circular separating segment as distinguished from the unit 144; of FIG- 1a.
It is to be understood, however, that this may be truly flat to cooperate with the septagonal segment structure 144.
The extended scope of invention relative to the cast iron piston would include the use of sintered metals with the ball in position during the sintering process. Inasmuch as the ball is of bearing grade steel, it will not be affected by the lower sintering temperatures.
After the sintering, the shrinkage of the parts caused by cooling to ambient temperature will be effective to produce the appropriate working clearances.
This embodiment of the invention can also be made of injection molded nylon, reinforced Teflon, or the like, also utilizing a steel ball. These materials have inherent lubricity or lubrication characteristics and accordingly appropriate operation clearances will be developed in operation due to this feature.
Relative to the sintering technique above, if the temperature is too high, it will of course destroy the temper of the ball. In those instances where it is desired to use or is necessary to use higher sintering temperatures that would destroy ball temper, the piston can be manufactured separately first. Then, a three piece ball can be inserted, although the latter procedure will be a little more expensive from the manufacture and assembly standpoint.
The fourth embodiment piston As shown in FIGURE 29, a cast iron or steel piston W4 having integral central body and end piston portions is provided. This is then radially bored as at 496. T hereafter, an appropriate ball 4% is dropped in position and babbitt poured around it to provide a perfectly matched socket. The babbitt on cooling will provide proper work clearance. The babbitt i illustrated by the cross hatch lines 410.
It is recognized relative to this embodiment, of course, that under high pressures babbitt will eventually wear. It the hole 4% therefore is of about the same diameter as the diameter of the ball, there will be point-to-point steel contact between the ball and the piston on each side. The babbitt forms the remainder of the cradle, and therefore the point will be helpful to support the load and reduce wear.
16 It is to be understood, of course, that this unit can utilize a bore 412, produced or cleaned up after the babbitt pouring operation to provide lubrication and mechanical support by a film of oil between the surface of the ball and the babbitt.
The fifth embodiment piston Another very practical piston for use in the present invention is shown in FIGURE 30. This utilizes stock hex rod material of tool steel grade.
The raw stock is provided with stepped and chamfered screw sockets 41d, threaded at the small diameter to receive fiat head screws 416 that hold the ball in an appropriate socket as illustrated. The ball socket is provided by an appropriate straight bore with a spherical bottom actually cradling the lower half thereof. The ball socket is designated by the reference numeral 418.
After the center body portion 426 of the unit is thus manufactured, the end piston portions 422 are produced by suitable lathe and grinding operation.
It will be noted that annular grooves 424- are provided, for the purpose of catching dirt that may be entrained in the material being pumped; this prevents scoring of the cylindrical piston surfaces and the cylinder bores which of course as will be understood, in order to carry the loads imposed, are machined to very close tolerances relative to one another.
ADVANTAGES OF THE PRESENT INVENTION It is believed, of course, that the advantages inherent in the invention are evident from the foregoing description. However, a brief resume will be provided at this point to bring them into sharpest focus for the reader. These are as follows:
A wobble plate pump of adjustable stroke incorporating a variable spring load to cock the wobble plate and thereby establish working pressure. This is very simply changed by adjustment screw exposed on each end of the pump.
The scope of the invention includes a mechanically or hydraulically biased separating segment to automatically establish proper working contact or clearance between the cylinder blocks and the pump head.
The body of the pump is made of aluminum or other materials of appropriate expansion characteristic to provide a proper working clearance between the cylinder blocks and heads when the unit undergoes temperature changes such as heating under load.
The pistons are prevented from rotating by a novel separator segment which also can be hydraulically biased and split to respond to pressures which the pump is called upon to produce.
Additionally, the heads of the pump are identical for minimum tooling costs.
Further, cross-over tubes are provided and sealed in a very unique manner, together with coaxial through bolts giving further economies of manufacture and production and minimizing leakage openings.
Further, an important advantage of the invention is the unique movable separator segment with its antivibration and servo-action characteristics. These are in several forms.
A further and important advantage of the invention resides in its adaptability to use a number of different kinds of pistons made in a very economical manner and Y of non-lubricating liquids, Teflon, Delrin, nylon, and other inherently lubricating synthetic resins, can be employed.
It is again noted that a very important aspect of the invention resides in the circumferentially movable segment to automatically enlarge the exhaust cavity and 17 optionally reduce the cubage of the inlet cavity to damp destructive vibrations and provide servo-action in pumps.
EXTENDED SCOPE OF INVENTION The prior description has specifically related to a wobble plate pump capable of sustained duty at 1000 pounds per square inch pressure at a capacity of several gallons per minute. This particular unit would be very useful in a central hydraulic system for an automobile.
However, it is to be clearly understood that the ex tended scope of invention will include application of the inventive principles involved to a broad range of reciprocating piston pumps wherein a cross-over between an exhaust and inlet manifold segment is productive of destructive fluid hammer, and where an assist is necessary for controlling or erecting the wobble plate.
I claim:
1. In fluid handling mechanism,
a cylinder head having a working face,
an annular groove in said face defining inlet and exhaust ports,
means disposed in said annular groove separating said ports from one another,
1 at least one of said means being movable under exhaust pressure in a direction enlarging the volume of the exhaust port,
means limiting pressure movement of said first named means,
means biasing said first named means in a direction reducing the volume of said exhaust port,
means limiting said biasing movement,
a block carrying a cylinder and mounted to carry the cylinder in communication with first one and then the other of said ports,
pistons carried by said block,
means for moving sa d block,
and means operable to reciprocate said pistons during passage over said ports.
2. In fluid handling mechanism,
a hollow housing including a head with an interior working face,
inlet and exhaust manifold grooves in said face arranged in annular array and with spaced cross-over lands separating the ends thereof,
a recess in, said face spanning at least one of said lands,
means positioned in said recess and movable relative thereto.
said means defining faces exposed to respective ones of said grooves,
means biasing said first named means in a direction reducing the volume of said exhaust groove and enlarging the volume of the intake groove,
means limiting movement of said faces,
a cylinder block carried for rotation adjacent said face,
a piston carried by said block and operable in communication with said grooves,
and means operably connected with said piston to impart reciprocation thereto.
3. The invention of claim 2 wherein said first named means comprises a disc-like element and said recess is of a configuration to rotatably receive the same in intimate contacting relation to provide a seal between the inlet and exhaust manifold grooves,
a first notch in the periphery of said disc spanning said exhaust groove,
a second notch in the periphery of said disc partially spanning said inlet groove,
and said limiting means limiting rotary movement of said first named means whereby said notches are retained in at least partially spanning relation to said grooves.
4. In fluid handling mechanism,
a hollow housing including a cylinder head with an internal Working face,
inlet and exhaust manifold grooves in said face arranged in circular array and with spaced lands separating the ends thereof,
a circular recess in said face spanning one of said lands,
a disc-like means positioned in said recess and rotatable therein in intimate contacting, seal relation and with the top surface level with said face,
a bore in said head coaxial to said recess and separated therefrom by a transverse Web,
a coaxial aperture in said web,
a stem connected to said means and extending through said aperture,
a nut threaded on the free end of said stern,
a torsion spring having one end secured to said nut and the other end to said Web,
said means defining notch-like faces exposed to respective ones of said grooves,
means limiting rotary movement of said first named means whereby said faces are retained in at least partially spanning relation to said grooves,
a power shaft extending through said head and carrying a cylinder block for rotation adjacent said head face,
a piston carried by said block and operable in communication with said grooves,
and means operably connected with said piston to impart reciprocation thereto during rotation of said block.
5. In fluid handling mechanism,
a hollow housing including a head with an internal Working face, i
inlet and exhaust manifold grooves in said face arranged in annular array and with spaced cross-over lands separating the ends thereof,
a cylindrical recess in said face spanning one of said lands, a cylindrical rotor in said recess in intimate contacting relation to provide a seal between said grooves, said rotor including notch-like faces exposed to respective ones of said grooves,
means rotatably biasing said rotor in a direction to ret duce the volume of said exhaust groove and enlarge the volume of the inlet groove,
means limiting'movement of said rotor,
a cylinder block carried for rotation adjacent said face,
a piston carried by said block and operable in communication with said grooves,
and means operably connected with said piston to impart reciprocation thereto.
6. In fluid handling mechanism,
a cylinder head having a working face,
opposed inlet and exhaust manifold grooves in said face arranged in annular array and with spaced lands separating the ends thereof,
two recesses in said face, one spanning each of said lands,
means positioned in each recess and movable relative thereto and blocking flow between said grooves,
each of said means defining two spaced, notch-like faces exposed to respective ones of said grooves,
stop means operable to limit movement of said first named means,
means between said stop means and said first named means biasing said first named means to a central position relative to the ends of said grooves,
a cylinder block carried for rotation adjacent said face,
a piston carried by said block and operable in communication with said grooves,
and means operably connected with said piston to impart reciprocation thereto.
7. In fluid handling mechanism,
a hollow housing including a cylinder head with an interior working face,
an annular groove in said face,
means defining a first land extending part way across said groove to separate said groove at one point into an inlet manifold and an exhaust manifold,
a ring member rotatable in said groove between said land and the other side of said groove and defining a land movable in said groove and separating said groove at another point into said inlet and exhaust manifolds, 7
means limiting rotatable movement of said ring member,
means rotatably biasing said ring member in a direction reducing the volume of said exhaust manifold and enlarging the volume of the inlet manifold,
stop means limiting said movement,
a cylinder block carried for rotation adjacent said face,
a piston carried by said block and operable in communication with said manifolds,
and means operably connected with said piston to impart reciprocation thereto.
8. The invention of claim 7,
wherein said means defining said first land comprises a second ring member rotatable against one side in said groove with the first land movable therewith,
stop means carried by said head,
and resilient means between said stop means and said ring members biasing said ring members to a central position relative to the ends of said grooves.
9. In fluid handling mechanism,
a cylinder head having a working face,
inlet and exhaust manifold grooves in said face arranged in annular array and with spaced lands separating the ends thereof,
an elongated recess in said face in communication with an outer end of the exhaust groove,
said recess ofiset radially relative to said grooves,
means mounted in said recess and movable longitudinally thereof,
means mounting said first named means for rotation,
means biasing said first named means toward said exhaust groove,
means biasing said first named means in a direction axially out of said groove,
a cylinder containing block mounted to move the cylinder thereof in a manner successively traversing said inlet and exhaust grooves,
means for moving said block,
and means operable to reciprocate said piston during passage of said grooves to fill the cylinder through said inlet groove and empty the cylinder through said exhaust groove.
10. In fluid handling mechanism,
a cylinder head having a working face,
an annular groove in said face defining opposed inlet and exhaust orts,
an elongated recess in said face and spanning said groove and offset radially relative to said groove,
means mounted in said recess for longitudinal movement therein and effective to isolate said inlet and exhaust ports from one another,
means mounting said first named means for rotation,
means biasing said first named means toward a central position in said recess,
a cylinder containing block mounted to move the cylinder thereof in a manner successively traversing said inlet and exhaust ports,
a piston in said cylinder block,
means for moving said block,
and means operable to reciprocate said piston during passage of said ports to fill the cylinder through said inlet port and empty the cylinder through said exhaust port.
References Cited by the Examiner (Corresponding British Patent 938,596Oct. 2, 1963) LAURENCE V. EFNER, Primary Examiner.

Claims (1)

1. IN FLUID HANDLING MECHANISM, A CYLINDER HEAD HAVING A WORKING FACE, AN ANNULAR GROOVE IN SAID FACE DEFINING INLET AND EXHAUST PORTS, MEANS DISPOSED IN SAID ANNULAR GROOVE SEPARATING SAID PORTS FOR ONE ANOTHER, AT LEAST ONE OF SAID MEANS BEING MOVABLE UNDER EXHAUST PRESSURE IN A DIRECTION ENLARGING THE VOLUME OF THE EXHAUST PORT, MEANS LIMITING PRESSURE MOVEMENT OF SAID FIRST NAMED MEANS, MEANS BIASING SAID FIRST NAMED MEANS IN A DIRECTION REDUCING THE VOLUME OF SAID EXHAUST MOVEMENT, MEANS LIMITING SAID BIASING MOVEMENT, A BLOCK CARRYING A CYLINDER AND MOUNTED TO CARRY THE CYLINDER IN COMMUNICATION WITH FIRST ONE AND THEN THE OTHER OF SAID PORTS, PISTONS CARRIED BY SAID BLOCK, MEANS FOR MOVING SAID BLOCK, AND MEANS OPERABLE TO RECIPROCATE SAID PISTONS DURING PASSAGE OVER SAID PORTS.
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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3749523A (en) * 1971-12-27 1973-07-31 Caterpillar Tractor Co Swash plate gas compressor
US3905274A (en) * 1974-01-28 1975-09-16 Gen Motors Corp Rotary timing valve
US5992150A (en) * 1996-12-23 1999-11-30 Tecumseh Products Company Transaxle with hydrostatic transmission
US20100139500A1 (en) * 2007-08-29 2010-06-10 G.S.G. S.R.L. Apparatus for producing so-called soft ice cream and process for feeding a relative mixture
US20100147010A1 (en) * 2007-08-29 2010-06-17 G.S.G. S.R.L. Heat exchanger device for treating liquid food mixtures
WO2014162083A1 (en) * 2013-04-04 2014-10-09 Hydro Leduc Hydraulic pump with double direction of rotation

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US2388644A (en) * 1943-05-08 1945-11-06 Roessler George Hydraulic pump, fluid motor, or compressor
US2456109A (en) * 1944-02-28 1948-12-14 Cecil C Buckner Fluid pump
US2619041A (en) * 1946-09-14 1952-11-25 Denison Eng Co Hydraulic apparatus
US2674196A (en) * 1951-10-10 1954-04-06 Oilgear Co Piston assembly for axial type hydrodynamic machines
US2847942A (en) * 1953-04-21 1958-08-19 American Brake Shoe Co Means of providing air purging in piston pump
US2910008A (en) * 1954-12-23 1959-10-27 Bendix Aviat Corp Pump
FR1247031A (en) * 1959-01-14 1960-11-25 Vickers Inc Motion transmission
US3063381A (en) * 1958-09-24 1962-11-13 New York Air Brake Co Engine
US3106138A (en) * 1960-06-27 1963-10-08 Hans Toma Piston type hydrostatic power units
US3113491A (en) * 1960-06-18 1963-12-10 Guldner Motoren Werke Aschaffe Piston for a piston pump
US3120816A (en) * 1959-04-16 1964-02-11 Council Scient Ind Res Hydraulic pumps and motors

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2388644A (en) * 1943-05-08 1945-11-06 Roessler George Hydraulic pump, fluid motor, or compressor
US2456109A (en) * 1944-02-28 1948-12-14 Cecil C Buckner Fluid pump
US2619041A (en) * 1946-09-14 1952-11-25 Denison Eng Co Hydraulic apparatus
US2674196A (en) * 1951-10-10 1954-04-06 Oilgear Co Piston assembly for axial type hydrodynamic machines
US2847942A (en) * 1953-04-21 1958-08-19 American Brake Shoe Co Means of providing air purging in piston pump
US2910008A (en) * 1954-12-23 1959-10-27 Bendix Aviat Corp Pump
US3063381A (en) * 1958-09-24 1962-11-13 New York Air Brake Co Engine
FR1247031A (en) * 1959-01-14 1960-11-25 Vickers Inc Motion transmission
GB938596A (en) * 1959-01-14 1963-10-02 Vickersi I Improvements in or relating to hydraulic pumps or motors
US3120816A (en) * 1959-04-16 1964-02-11 Council Scient Ind Res Hydraulic pumps and motors
US3113491A (en) * 1960-06-18 1963-12-10 Guldner Motoren Werke Aschaffe Piston for a piston pump
US3106138A (en) * 1960-06-27 1963-10-08 Hans Toma Piston type hydrostatic power units

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3749523A (en) * 1971-12-27 1973-07-31 Caterpillar Tractor Co Swash plate gas compressor
US3905274A (en) * 1974-01-28 1975-09-16 Gen Motors Corp Rotary timing valve
US5992150A (en) * 1996-12-23 1999-11-30 Tecumseh Products Company Transaxle with hydrostatic transmission
US20100139500A1 (en) * 2007-08-29 2010-06-10 G.S.G. S.R.L. Apparatus for producing so-called soft ice cream and process for feeding a relative mixture
US20100147010A1 (en) * 2007-08-29 2010-06-17 G.S.G. S.R.L. Heat exchanger device for treating liquid food mixtures
US8316761B2 (en) * 2007-08-29 2012-11-27 G.S.G. S.R.L. Apparatus for producing so-called soft ice cream and process for feeding a relative mixture
WO2014162083A1 (en) * 2013-04-04 2014-10-09 Hydro Leduc Hydraulic pump with double direction of rotation
FR3004224A1 (en) * 2013-04-04 2014-10-10 Hydro Leduc HYDRAULIC PUMP WITH DOUBLE DIRECTION OF ROTATION

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