US3800665A - Fluid pressure operated reciprocatory motor - Google Patents

Fluid pressure operated reciprocatory motor Download PDF

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US3800665A
US3800665A US3800665DA US3800665A US 3800665 A US3800665 A US 3800665A US 3800665D A US3800665D A US 3800665DA US 3800665 A US3800665 A US 3800665A
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valve
cylinder
piston
fluid
power cylinder
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Ruden N Von
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VON RUDEN Manufacturing CO
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VON RUDEN Manufacturing CO
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01BMACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B17/00Reciprocating-piston machines or engines characterised by use of uniflow principle
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01BMACHINES OR ENGINES, IN GENERAL OR OF POSITIVE-DISPLACEMENT TYPE, e.g. STEAM ENGINES
    • F01B17/00Reciprocating-piston machines or engines characterised by use of uniflow principle
    • F01B17/02Engines
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03CPOSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
    • F03C1/00Reciprocating-piston liquid engines
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03CPOSITIVE-DISPLACEMENT ENGINES DRIVEN BY LIQUIDS
    • F03C1/00Reciprocating-piston liquid engines
    • F03C1/08Distributing valve-gear peculiar thereto
    • F03C1/14Distributing valve-gear peculiar thereto by driving liquid of engine

Abstract

Structure including a body having a power cylinder, a reversing valve cylinder and a pilot valve cylinder, a power piston in the power cylinder and reversing and pilot valves axially moveable in the reversing and pilot valve cylinders respectively. The body defines an inlet port for connection to a fluid pump, and one or more outlet ports for connection to a fluid reservoir. Reciprocatory movement of the power piston is controlled by the reversing valve which in turn is controlled by the pilot valve. Operation of the pilot valve is controlled by a pair of piston operated check valves.

Description

United States Patent [191 Von Ruden 1 Apr. 2, 1974 FLUID PRESSURE OPERATED 3,185,040 5/1965 Ligon 91/305 RECIPROCATORY MOTOR 3.540349 lH1970 Pennther 91/306 Primary Examiner-Paul E. Maslousky Attorney, Agent, or Firm-Merchant, Gould, Smith & Edell [57] ABSTRACT Structure including a body having a power cylinder, a reversing valve cylinder and a pilot valve cylinder, 21 power piston in the power cylinder and reversing and pilot valves axially moveable in the reversing and pilot valve cylinders respectively. The body defines an inlet port for connection to a fluid pump, and one or more outlet ports for connection to a fluid reservoir. Reciprocatory movement of the power piston is controlled by the reversing valve which in turn is controlled by the pilot valve. Operation of the pilot valve is controlled by a pair of piston operated check valves.

1 Claim, 1 Drawing Figure PATENTEU APR 2 I974 l FLUID PRESSURE OPERATED RECIPROCATORY MOTOR BACKGROUND OF THE INVENTION This invention is in the nature of an improvement on reciprocatory fluid motors of the type disclosed in U. S. Pat. No. 3,165,978, issued Jan. 19, 1965, to me and Jan Boers. The motor disclosed in the patent operates very satisfactorily, but the piston and piston rod structure thereof is somewhat difficult and expensive to produce with the accuracy required.

SUMMARY OF THE INVENTION An important object of this invention is the provision of a fluid pressure operated reciprocatory motor having reversing control mechanism that is more simple and inexpensive to produce than heretofore, and which is highly efficient in operation and durable in use. To this end I provide structure including a body having therein a power cylinder, and a plunger rod equipped piston axially moveable in the power cylinder, the plunger rod extending outwardlythrough a bore in the body. Reversing and pilot valve cylinders or chambers have axially moveable reversing and pilot valves or spools respectively therein. Fluid passages connect the reversing and pilot valve cylinders with fluid inlet and outlet ports, and other fluid passages interconnect the pilot and reversing valve cylinders and power cylinder. A pair of passages connect opposite ends of the power cylinder each to a different end of the pilot valve cylinder, each of these passages having a check valve therein. The power piston is provided at its axially opposit e ends with portions that mechanically impart opening movements to each check valve at the end of each reciprocal movement of the power piston, to permit movement of the pilot piston in a direction to cause reversing movement to be imparted under fluid pressure to the reversing valve. Each check valve is opened by fluid pressure responsive to mechanical opening of the other check valve, so that fluid is discharged from one end of the pilot valve cylinder through the mechanically opened check valve and supplied to the opposite end of the pilot valve cylinder through the fluid pressure opened one of the check valves,

DESCRIPTION OF THE DRAWING The single FIGURE of the drawing is a hydraulic diagram, some parts being shown in side elevation, and some parts being shown in section.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Body structure, indicated generally by the numeral 1, defines a power cylinder 2, a reversing valve cylinder 3, and a pilot valve cylinder 4. A power piston is axially slideably mounted in the power cylinder 2 and is provided with an axially projecting piston or plunger rod 6 that extends through a bore 7 in the body structure 1. Although not shown, the piston rod 6 may be assumed to be adapted for connection to any suitable device requiring reciprocatory or oscillatory movement. Opposite ends 8 and 9 of the power cylinder 2 are diametrically reduced for reception of hub portions 10 and 1 l of the piston 5, the bore 7 having a diametrically enlarged bore portion 12 that opens into the portion 8 of the power cylinder 2 and which is adapted to loosely receive a tubular cam member 13 welded or otherwise rigidly mounted on the end of the piston rod 6 adjacent the hub portion 10 of the piston 5. The cam member 13 is formed to provide a frusto-conical cam surface 14 for a purpose which will hereinafter become apparent. A boss 15 projects axially outwardly of the piston hub portion 11 and is provided with an axially outwardly projecting pin 16.

The body structure 1 is formed to provide a fluid inlet port 17 from which a fluid passage 18 extends to the longitudinally central portions of the reversing valve cylinder 3 and the pilot valve cylinder 4. A pair of fluid passages 19 and 20 extend from the reduced end portions 8 and 9 respectively of the power cylinder 2 to the reversing valve cylinder 3 in spaced relationship to the inlet passage 18 and at opposite sides of the inlet passage 18. In like manner, a pair of fluid passages 21 and 22 extend from opposite end portions of the reversing valve cylinder 3 to the longitudinally central portion of the pilot valve cylinder 4 in spaced relation to diametrically opposite sides of the inlet passage 18 longitudinally of the pilot valve cylinder 4. A pair of outlet passages 23 and 24 communicate with the reversing valve cylinder 3 and with outlet ports 25. The passage 23 is disposed to communicate with the cylinder 3 between the adjacent ends of the fluid passages 19 and 21, the passage 24 communicating with the cylinder 3 intermediate the adjacent ends of the fluid passages 20v and 22. Likewise, a pair of outlet passages 26 and 27 extend from the pilot valve cylinder 4 to outlet ports 28, the passage 26 communicating with the cylinder 4 in spaced relation to the adjacent end of the passage 21 and the adjacent end of the cylinder 4, the passage 27 communicating with the cylinder 24 in spaced relation to the adjacent end of the passage 22 and the adjacent end of the cylinder 4. Although not shown, it may be assumed that the outlet ports and 28 maybe a single outlet port adapted for connection to a fluid reservoir not shown, a plurality of outlet ports 25 and 28 being shown for the purpose of convenience.

A spool-like reversing valve 29 is mounted in the reversing valve cylinder 3 for axial sliding movements therein, and comprises a central valve piston 30 of relatively short axial length and a pair of cooperating valve pistons 31 and 32 of relatively long axial length adjacent opposite ends of the valve 29. The valve pistons 31 and 32 cooperate with the central valve piston 30 to define the opposite ends of respective grooves 33 and 34 each having an axial length substantially equal to the axial length of one of the valve pistons 31 and 32. At its opposite ends, the reversing valve 29 is formed to provide axial bosses 35 that are adapted to engage adjacent ends of the cylinder 3 to limit axial movement of the reversing valve 29 in opposite directions. The piston 30 is formed to provide acentral annular groove 30a.

An elongated spool-like pilot valve, indicated generally at 36, is disposed for axial sliding movements in the pilot valve cylinder 4, and comprises a central piston 37 of relatively short axial length, a pair of axially relatively long pistons 38 and 39, and end bosses at the opposite ends of the valve 36 and adapted to engage adjacent end walls of the pilot valve cylinder 4 to limit axial movement of the valve 36 in opposite directions. The valve 36 is similar to the valve 29, except that the piston 37 is devoid of a central annular groove like the groove 30a of piston 30. The pistons 37 and 38 define opposite ends of a circumferential channel 41, the pistons 37 and 39 defining opposite end walls of a circumferential channel 42. It should here be noted that the central pistons 30 and 37 of both valves 29 and 36 have an axial length slightly greater than the width or diameter of the inlet passage 18, the pistons 30 and 37 being disposed to pass over the inlet passage 38 during axial movements in their respective cylinders 3 and 4. The annular groove 30a insures continuous flow of fluid through the passage 18 during movement of the piston 30 over the passage 18.

The body structure 1 is formed to provide a pair of fluid passages 43 and 44 that extend from opposite ends of the pilot valve cylinder 4 each toward an opposite end of the power cylinder 2. Preferably, and as shown, the passage 43 extends from the end of the pilot valve cylinder 4 adjacent the valve piston 39 toward the enlarged bore portion 12 of the power cylinder 2, the

passage 44 extending from the pilot valve cylinder 4 adjacent the valve piston 38 toward the diametrically reduced portion 9 of the power cylinder 2. A check valve 45 is interposed in the fluid passage 43 and comprises a casing 46, a ball valve element 47, and a coil compression spring 48 that yieldingly urges the ball valve element 47 into seating engagement with a valve seat portion 49. As shown, a passage portion 50 extends from the valve seat 49 to the enlarged bore portion 12, and contains a valve actuator 51 having a portion projecting radially inwardly into rolling or sliding engagement with the piston rod 6 Within the enlarged bore portion 12.

A second check valve 52 is interposed between the end portion 9 of the power cylinder 2 and the adjacent end of the fluid passage 44, and comprises a valve body 53 defining a valve seat 54 from which extends a passage portion 55 to the interior of the power cylinder 2 in axial alignment with the pin 16 on the piston 5. A valve ball element 56 is urged into seating engagement with valve seat 54 by a coil compression spring 57 that has abutting engagement with a screw plug 58 that is screw threaded into the body structure 1 to form an abuttment for the spring 57 and to secure the valve housing 53 in the body structure 1. A cross-passage 59 in the valve housing 53 provides communication between the fluid passage 54 and the passage portion 55 when the valve ball element 56 is in an open position.

OPERATION For imparting reciprocatory movement to the piston and piston rod 6, it is assumed that the inlet port 17 is in communication with the discharge of a source of fluid pressure, such as a pump, not shown, and that the outlet ports 25 and 28 are connected to a fluid reservoir, also not shown, from which the pump receives fluid. With the pilot valve 36 and reversing valve 29 positioned as shown in the drawing, fluid under pressure moves through the inlet passage 18, groove 34, and through fluid passage to the end portion 9 of the power cylinder 2 to move the piston 5 and piston 6 in a direction from the right to the left with respect to the drawing, and as shown by the arrow on the piston rod 6. Fluid under pressure is also contained within the upper portion of the passage 18, circumferential groove 42, fluid passage 22 and the right-hand end of the reversing valve cylinder 3 to hold the reversing valve 29 in its position shown. Fluid is contained under pressure in the fluid passage 44 and the end of the pilot valve cylinder 4 adjacent the pilot valve piston 38. However, fluid in the opposite end of the pilot valve cylinder 4 and in the passage 43 is prevented from discharge by the check valve 45, so that the pilot valve 36 is hydraulically locked in place.

As the piston 5 approaches the end of its movement toward the left with respect to the drawing, the frustoconical cam portion 14 of the cam member 13 engages the adjacent end of the actuator 51 and moves the same radially outwardly to move the valve ball member 47 to a valve open position away from seating engagement with the valve seat 49. At the same time, the check valve 52 is opened due to pressure of fluid in the adjacent end 9 of the power cylinder 2 so that fluid under pressure moves the pilot valve 36 toward the opposite end of the pilot valve cylinder 4. During this movement of the pilot valve 36, fluid in the opposite end of the cylinder 4. and in the passage 43 moves axially inwardly of the enlarged bore portion 12, and through the fluid passage 19, circumferential groove 33 in the reversing valve 29, and passage 23 to the adjacent outlet port 25. As the pilot valve 36 moves to the right, the piston 37 crosses the adjacent end of the inlet passage 18 and, when the pilot valve 36 is moved to its limit of movement to the right with respect to the drawing, the piston 37 is disposed so that the circumferential groove 42 is in register with the adjacent ends of the passages 22 and 27, the circumferential groove 41 being in register with the adjacent ends of the inlet passage 28 and fluid passage 21. Fluid under pressure then flows through the passage 18, circumferential groove 41, and fluid passage 21 to the end of the reversing valve cylinder 3 adjacent the piston 31 of the reversing valve 29. The opposite end of the reversing valve chamber 3 being exposed to the outlet passage 27, fluid under pressure will move the reversing valve 29 to the right with respect to the drawing until the center piston 30 moves across the inlet passage 18, the piston 31 closing off the outlet passage 23, and the circumferential groove 33 coming into register with the inlet passage 18 and fluid passage 19. At the same time, the circumferential groove 34 moves into register with the adjacent ends of the fluid passage 20 and outlet passage 24 so that the right end power cylinderportion 9 is in communication with the reservoir not shown. Fluid under pressure, moving through the fluid passage 19 into the power cylinder portion 8 imparts movement to the power piston 5 and piston rod 6 toward the right with respect to the drawing. In view of the fact that the fluid passage 20 is in communication with the outlet passage 24, so that a minimum fluid pressure exists in the adjacent end of the power cylinder 2, the check valve 52 closes to establish a fluid lock in the passage 44 to prevent movement of the pilot valve 36 in the opposite direction until the valve ball element 56 is unseated by engagement with the pin 16. As soon as the valve ball element 56 is unseated, fluid under pressure in the opposite end portion of the power cylinder 2 will move through the check valve 45 to move the pilot valve 36 toward the opposite end of the pilot valve cylinder 4 to cause reversal of the reversing valve 29 and reverse movement to be imparted to the power piston 5 and piston rod 6.

With the above arrangement, there is no deadcenter relationship of any of the moving parts, and the motor can be stopped and restarted with the piston 5 in any position longitudinally of the power cylinder 2. Further, pressure of the check valve springs 48 and 57 is not critical, it being only necessary that these be strong enough to close their respective valve ball elements against pressure of fluid being moved toward the, outlet ports 25.

If it is desired that the above-described motor utilize a piston rod at both ends of the power piston 5, it is only necessary that the opposite end of the body structure 1 be provided with a bore and counter-bore similar to the bore 7 and enlarged bore portion 12, and to that a second check valve 45 be substituted for the check valve 52 at the lower end portion of the passage 44. The second piston rod would of course be provided with a valve actuator engaging cam member similar to the cam member 13.

While l have shown a preferred embodiment of my fluid pressure operated reciprocatory motor, and briefly described a modified arrangement, it will be understood that the same is capable of further modification without departure from the spirit and scope of the invention, as defined in the claims.

What is claimed is:

1. In a fluid pressure operated reciprocatory motor:

c. said structure having inlet port means for connection to a source of fluid under pressure, outlet port means, and passage means connecting said inlet and outlet port means to said valve cylinders and connecting said reversing valve cylinder to said power cylinder;

d. a pilot valve and a reversing valve axially movable in respective ones of said valve cylinders;

e. said pilot valve having axially spaced valve pistons and intervening circumferential grooves for controlling flow of fluid to and from said reversing valve cylinder;

f. said reversing valve having axially spaced valve pistons and intervening circumferential grooves for controlling flow of fluid to and from said power cylinder and to said pilot valve cylinder;

g. said structure further having a pair of fluid passages each extending and communicating with a different chamber of said power cylinder to a different end of said pilot cylinder, said fluid passages being disposed to maintain a pressure balance at opposite ends of said pilot valve cylinder during movement of said power piston between opposite ends of said power cylinder;

h. a pair of check valves one each connecting one of said fluid passages to the adjacent end of said power cylinder, each of said check valves including a valve element movable between valve open and closed positions, one of said valve elements being movable generally radially relative to said piston receiving bore, the other of said valve elements moving axially of said power cylinder;

. said bore having a diametrically enlarged portion opening into said power cylinder;

j. a check valve actuator having a portion projecting into said enlarged bore portion and engaging said generally radially moving valve element;

k. a cam at one end of said piston for engagement with said check valve actuator to move its respective valve element in a valve openingdirection;

l. and a pin projecting axially from the other end of said piston for engagement with said axially moving valve element to move the same in a valve opening direction.

Claims (1)

1. In a fluid pressure operated reciprocatory motor: a. structure including Body means defining a power cylinder, a reversing valve cylinder, a pilot valve cylinder, and an axial piston rod receiving bore at one end of said power cylinder; b. a power piston axially movable in said power cylinder and having a piston rod in said bore axially movable with said piston; a chamber on each side of said power piston; c. said structure having inlet port means for connection to a source of fluid under pressure, outlet port means, and passage means connecting said inlet and outlet port means to said valve cylinders and connecting said reversing valve cylinder to said power cylinder; d. a pilot valve and a reversing valve axially movable in respective ones of said valve cylinders; e. said pilot valve having axially spaced valve pistons and intervening circumferential grooves for controlling flow of fluid to and from said reversing valve cylinder; f. said reversing valve having axially spaced valve pistons and intervening circumferential grooves for controlling flow of fluid to and from said power cylinder and to said pilot valve cylinder; g. said structure further having a pair of fluid passages each extending and communicating with a different chamber of said power cylinder to a different end of said pilot cylinder, said fluid passages being disposed to maintain a pressure balance at opposite ends of said pilot valve cylinder during movement of said power piston between opposite ends of said power cylinder; h. a pair of check valves one each connecting one of said fluid passages to the adjacent end of said power cylinder, each of said check valves including a valve element movable between valve open and closed positions, one of said valve elements being movable generally radially relative to said piston receiving bore, the other of said valve elements moving axially of said power cylinder; i. said bore having a diametrically enlarged portion opening into said power cylinder; j. a check valve actuator having a portion projecting into said enlarged bore portion and engaging said generally radially moving valve element; k. a cam at one end of said piston for engagement with said check valve actuator to move its respective valve element in a valve opening direction; l. and a pin projecting axially from the other end of said piston for engagement with said axially moving valve element to move the same in a valve opening direction.
US3800665D 1972-07-27 1972-07-27 Fluid pressure operated reciprocatory motor Expired - Lifetime US3800665A (en)

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Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4846045A (en) * 1987-12-07 1989-07-11 Mcneil (Ohio) Corporation Expansible chamber motor
EP1059425A3 (en) * 1999-06-11 2002-01-02 Checkpoint Fluidic Systems International, Ltd. Pilot control valve for controlling a reciprocating pump
US6736046B2 (en) 2002-10-21 2004-05-18 Checkpoint Fluidic Systems International, Ltd. Pilot control valve utilizing multiple offset slide valves
US20060005697A1 (en) * 2004-07-08 2006-01-12 Burns Patrick J Sr Fluid power unit having closed circuit
US20080267795A1 (en) * 2007-04-27 2008-10-30 Rusty Singer Positive Displacement Injection Pump

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2223792A (en) * 1938-04-12 1940-12-03 Dominion Eng Works Ltd Hydraulic apparatus for operating machine tools and the like
US3090364A (en) * 1960-03-28 1963-05-21 Lefevre Lorin Hydraulic engine
US3165978A (en) * 1962-11-15 1965-01-19 Von Ruden Mfg Co Fluid pressure operated reciprocatory motor
US3185040A (en) * 1963-04-15 1965-05-25 American Brake Shoe Co Hydraulic reciprocating system
US3540349A (en) * 1965-05-20 1970-11-17 Hermann Joseph Pennther Fluid-operated continuously actuated reciprocating piston drive

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2223792A (en) * 1938-04-12 1940-12-03 Dominion Eng Works Ltd Hydraulic apparatus for operating machine tools and the like
US3090364A (en) * 1960-03-28 1963-05-21 Lefevre Lorin Hydraulic engine
US3165978A (en) * 1962-11-15 1965-01-19 Von Ruden Mfg Co Fluid pressure operated reciprocatory motor
US3185040A (en) * 1963-04-15 1965-05-25 American Brake Shoe Co Hydraulic reciprocating system
US3540349A (en) * 1965-05-20 1970-11-17 Hermann Joseph Pennther Fluid-operated continuously actuated reciprocating piston drive

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4846045A (en) * 1987-12-07 1989-07-11 Mcneil (Ohio) Corporation Expansible chamber motor
EP1059425A3 (en) * 1999-06-11 2002-01-02 Checkpoint Fluidic Systems International, Ltd. Pilot control valve for controlling a reciprocating pump
US6736046B2 (en) 2002-10-21 2004-05-18 Checkpoint Fluidic Systems International, Ltd. Pilot control valve utilizing multiple offset slide valves
US20060005697A1 (en) * 2004-07-08 2006-01-12 Burns Patrick J Sr Fluid power unit having closed circuit
WO2006014514A2 (en) * 2004-07-08 2006-02-09 Burns Sr Patrick J Fluid power unit having closed circuit
WO2006014514A3 (en) * 2004-07-08 2007-01-04 Sr Patrick J Burns Fluid power unit having closed circuit
US7237470B2 (en) * 2004-07-08 2007-07-03 Burns Controls Company Fluid power unit having closed circuit
US20080267795A1 (en) * 2007-04-27 2008-10-30 Rusty Singer Positive Displacement Injection Pump
US8087345B2 (en) 2007-04-27 2012-01-03 Checkpoint Fluidic Systems International, Ltd. Positive displacement injection pump
US8966760B2 (en) 2007-04-27 2015-03-03 Checkpoint Fluidic Systems International, Ltd. Method of manufacturing a positive displacement injection pump

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