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US3570523A - Self-regulating reciprocator device - Google Patents

Self-regulating reciprocator device Download PDF

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Publication number
US3570523A
US3570523A US3570523DA US3570523A US 3570523 A US3570523 A US 3570523A US 3570523D A US3570523D A US 3570523DA US 3570523 A US3570523 A US 3570523A
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Prior art keywords
spool
bore
pistons
port
fluid
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Richard S Pauliukonis
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15BSYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/08Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor
    • F15B11/15Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor with special provision for automatic return
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/2496Self-proportioning or correlating systems
    • Y10T137/2544Supply and exhaust type
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/2496Self-proportioning or correlating systems
    • Y10T137/2559Self-controlled branched flow systems
    • Y10T137/265Plural outflows
    • Y10T137/2668Alternately or successively substituted outflow
    • Y10T137/2688Flow rate responsive
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10TTECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00Fluid handling
    • Y10T137/8593Systems
    • Y10T137/86389Programmer or timer
    • Y10T137/86405Repeating cycle
    • Y10T137/86413Self-cycling

Definitions

  • a device for transmitting pressurized fluid from a supply to receiver means such as a tank or a cylinder or the like, comprises a spool carrying at each end symmetrically opposing pistons of diameter larger than the diameter of the third piston located in the middle of said spool, the spool being moved in either direction by the working fluid pressure acting upon said spool to alternatingly feed either one or another port in the housing or to feed and to exhaust the transmitted fluid by additional ports provided, and in a self-regulated reciprocating action, such as found in the positive displacement' pumps or in the fluid power controls such as four-way valves however without external operators such as motor-driving pump or solenoid-operating valve, and serves a multipurpose duty in a variety of applications of this device.
  • Appropriate seals permanently positioned to remain engaged with pistons in all operating conditions are employed.
  • the present invention provides a device for transmitting pressurized fluid from fluid supply to receiver of any choice, such as a tank or an actuating cylinder, with or without exhaust means in a housing for escape of the transmitted fluid and without the use of external actuators such as motors or solenoids normally serving such devices. It is obviously desirable to provide devices of this type which require no external power to actuate, and are extremely simple, reliable and inexpensive. For example, if this device is used for fluid pumping as a positive displacement pump, the working fluid pressure acting upon the spool provided would create the necessary force tooperate such pump without the need of conventional pump driving means such as electric motors or the like representing considerable savings in initial cost and in subsequent operating and maintenance cost.
  • the present invention provides devices of this general type which are suitable for use in positive displacement pumps, in fluid power controls such as four-way self-regulating reciprocating valves or the like, and which enhance design simplicity, reliability and low cost.
  • FIGS. la and 1b illustrate cross-sectional views of a device embodying the invention combined with position change of a spool and representing a positive displacement pump.
  • FIGS. 2a and 2b show cross-sectional views with position change of spool of a four-way self-regulating reciprocating valve of this invention.
  • FIGS. 1a and 1b Shown in FIGS. 1a and 1b is a pump housing having a continuous central bore 11 symmetrically bored to receive slidably a symmetrical spool 12 with two opposing large diameter pistons 3 and 3a at each spool end and a smaller piston 4 situated midway for entering into the large housing bores 13a and 13b and smaller middle bore 14.
  • a pump housing having a continuous central bore 11 symmetrically bored to receive slidably a symmetrical spool 12 with two opposing large diameter pistons 3 and 3a at each spool end and a smaller piston 4 situated midway for entering into the large housing bores 13a and 13b and smaller middle bore 14.
  • provisions are made by means of grooves 16 and 16a to receive truarc rings and 15a which serve as spool stops and provide an easy spool installation and maintenance means.
  • the pump housing is provided with fluid infeed port 17 which terminates with orifice 17a in direct communication with housing bore l4 serving as port 19 feeding means via annulus 1d, and port 21 feeding means via annulus 20 both cases clearly illustrated in FIGS. la and lb.
  • Seals 22, 22a and 22b of O-ring configuration or the like and of appropriate size serve as positive sealing means during the axial spool sliding when the device is in operation.
  • Port 17 may be connected to a supply of pressurized hydraulic fluid or other liquid to feed a receiver as shown in FIG. la, the receiver being connected to port 19.
  • the fluid flow will proceed from port 17, via orifice 17a and annulus 18 into the port 19 serving receiver, while port 21 is sealed from the fluid supply by the seal 22 secured to piston 4 and bore 13b is sealed by seal 22b secured to piston 3.
  • FIG. 1a indicates that the pressure in annulus id is small which usually preceeds a pressure buildup with fluid influx, at which time increase in fluid flow raises the pressure inside the annulus l8 and also pressure acting upon piston 3, gradually increasing end force over piston 3 facing annulus l8 and finally shifting spool to the position illustrated in F lG. 1b when this force outbalances resistances present.
  • FIGS. 2a and 2b Shown in FIGS. 2a and 2b are arrangements similar to those identified in FIGS. la and lb with exception of housing 30 which includes additional ports for fluid flow as required by a typical four-way valve in which spool shifting opens additional exhaust ports 43 and 44 for cylinder one" and cylinder two exhaust respectfully.
  • the spool configuration here is identical to the spool configuration described when discussing FIGS. la and lb.
  • the operation of the device in a fourway valve envelop is identical in terms of pressure forces act ing upon pistons and shifting spool to either cylinder one feeding port 33 while cylinder two port 41 is exhausting via cylinder two exhaust port 44, or vice versa, and will need no further discussion.
  • the components shown in FIG. 2a and 2 are as follows:
  • valve housing 30 having a continuous central bore 31 symmetrically bored to receive slidably a symmetrical spool 32 with two opposing large diameter pistons 6 and tie at each spool end and a smaller piston 40 situated midway for entering into the large housing bores 33a and 33b and a smaller middle bore 34.
  • provisions are made by means of grooves 36 and 36a to receive truarc rings 35 and 35a which serve as spool stops and provide an easy spool installation and maintenance means.
  • valve housing is provided with fluid infeed port 37 which terminates with orifice 37a in direct communication with housing bore 34 serving annulus 38 to feed cylinder one" port 39 in FIG. 2a and also serving annulus 50 to feed cylinder two port 41 in FIG. 2b.
  • Seals 42, 42a and 42b of O-ring configuration or the like and of appropriate size serve as positive sealing means during the axial spool sliding and change of spool position during the valve operation.
  • FIG. 2a shows cylinder one being energized by the working fluid flowing from port 37 via orifice 37a and annulus 38 into port 39 while the cylinder two at port 41 is to exhaust via port 44, and the seals 42 and 42b seal off the communications with other than ports 37 and 39.
  • FIG. 2b shows spool 32 shifted and cylinder one exhausting from cylinder one port 39 via bore 43a and cylinder one" exhaust port 43 while the cylinder two" at port 41 is feeding via annulus 50 in direct communication with infeed port 37.
  • the position change and cylinder feeding and exhaust in a continuous self-regulated reciprocating action of the spool will continue for as long as the pressurized fluid enters port 37 to act upon the pistons 6 and 6a of this valve.
  • a spool valve device including means defining a bore having a relatively small-diameter central portion and relatively large-diameter end portions, a spool received for reciprocation in said bore, said spool having a relatively small-diameter upon by fluid pressure between the inlet port and that outlet port which is not blocked by the central piston so as to shift the spool.
  • a device as in claim 1 including seals such as O-rings spaced from each other along the spool so that each is positioned to remain engaged with one of said pistons during the spool movement axially under all operating conditions.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Multiple-Way Valves (AREA)

Abstract

A device for transmitting pressurized fluid from a supply to receiver means such as a tank or a cylinder or the like, comprises a spool carrying at each end symmetrically opposing pistons of diameter larger than the diameter of the third piston located in the middle of said spool, the spool being moved in either direction by the working fluid pressure acting upon said spool to alternatingly feed either one or another port in the housing or to feed and to exhaust the transmitted fluid by additional ports provided, and in a self-regulated reciprocating action, such as found in the positive displacement pumps or in the fluid power controls such as four-way valves however without external operators such as motor-driving pump or solenoidoperating valve, and serves a multipurpose duty in a variety of applications of this device. Appropriate seals permanently positioned to remain engaged with pistons in all operating conditions are employed.

Description

United States Patent 3,326,236 6/1967 Beckett Richard S. Pauliukonis 6660 Greenbriar Drive, Cleveland, Ohio 44130 July 16,1969
Mar. 16, 1971 [72] Inventor Appl. No. Filed Patented [54] SELF-REGULATING RECIPROCATOR DEVICE 2 Claims, 4 Drawing Figs.
References Cited UNITED STATES PATENTS Primary Examiner-Alan Cohan ABSTRACT: A device for transmitting pressurized fluid from a supply to receiver means such as a tank or a cylinder or the like, comprises a spool carrying at each end symmetrically opposing pistons of diameter larger than the diameter of the third piston located in the middle of said spool, the spool being moved in either direction by the working fluid pressure acting upon said spool to alternatingly feed either one or another port in the housing or to feed and to exhaust the transmitted fluid by additional ports provided, and in a self-regulated reciprocating action, such as found in the positive displacement' pumps or in the fluid power controls such as four-way valves however without external operators such as motor-driving pump or solenoid-operating valve, and serves a multipurpose duty in a variety of applications of this device. Appropriate seals permanently positioned to remain engaged with pistons in all operating conditions are employed.
SELF-REGULATING RECIPROCATOR DEVICE The present invention provides a device for transmitting pressurized fluid from fluid supply to receiver of any choice, such as a tank or an actuating cylinder, with or without exhaust means in a housing for escape of the transmitted fluid and without the use of external actuators such as motors or solenoids normally serving such devices. It is obviously desirable to provide devices of this type which require no external power to actuate, and are extremely simple, reliable and inexpensive. For example, if this device is used for fluid pumping as a positive displacement pump, the working fluid pressure acting upon the spool provided would create the necessary force tooperate such pump without the need of conventional pump driving means such as electric motors or the like representing considerable savings in initial cost and in subsequent operating and maintenance cost.
The present invention provides devices of this general type which are suitable for use in positive displacement pumps, in fluid power controls such as four-way self-regulating reciprocating valves or the like, and which enhance design simplicity, reliability and low cost.
These and other objects and advantages of the invention will become more fully apparent from the following description of the embodiment of the invention, taken together with the accompanying drawings.
In the drawings:
FIGS. la and 1b illustrate cross-sectional views of a device embodying the invention combined with position change of a spool and representing a positive displacement pump.
FIGS. 2a and 2b show cross-sectional views with position change of spool of a four-way self-regulating reciprocating valve of this invention.
Shown in FIGS. 1a and 1b is a pump housing having a continuous central bore 11 symmetrically bored to receive slidably a symmetrical spool 12 with two opposing large diameter pistons 3 and 3a at each spool end and a smaller piston 4 situated midway for entering into the large housing bores 13a and 13b and smaller middle bore 14. At the extreme end of each large diameter bore provisions are made by means of grooves 16 and 16a to receive truarc rings and 15a which serve as spool stops and provide an easy spool installation and maintenance means.
The pump housing is provided with fluid infeed port 17 which terminates with orifice 17a in direct communication with housing bore l4 serving as port 19 feeding means via annulus 1d, and port 21 feeding means via annulus 20 both cases clearly illustrated in FIGS. la and lb.
Seals 22, 22a and 22b of O-ring configuration or the like and of appropriate size serve as positive sealing means during the axial spool sliding when the device is in operation.
Port 17 may be connected to a supply of pressurized hydraulic fluid or other liquid to feed a receiver as shown in FIG. la, the receiver being connected to port 19. The fluid flow will proceed from port 17, via orifice 17a and annulus 18 into the port 19 serving receiver, while port 21 is sealed from the fluid supply by the seal 22 secured to piston 4 and bore 13b is sealed by seal 22b secured to piston 3.
The operation of this device will initiate when the force created by the working pressure of the fluid inside the annulus l3 exerts upon piston 3 a force difference that overcomes pressure force acting upon opposing piston 3a including friction created by seals. FIG. 1a indicates that the pressure in annulus id is small which usually preceeds a pressure buildup with fluid influx, at which time increase in fluid flow raises the pressure inside the annulus l8 and also pressure acting upon piston 3, gradually increasing end force over piston 3 facing annulus l8 and finally shifting spool to the position illustrated in F lG. 1b when this force outbalances resistances present. As can be seen from FIG. llb, the fluid flow now will proceed from port 17 via orifice 17a, annular space 24) and into receiver connected to port 21 while port 19 is sealed from port 17 by a seal 22 and bore 13a is sealed by seal 22a of piston 3a. Again, when the force created by the working fluid pressure inside annulus 20 upon the piston 3a outbalances resistances offered by the piston 3 force including seal friction, the spool will shift to return to the original position as shown in FIG. la. Obviously than the shifting of spool by the working fluid pressure will continue for as long as the supply of fluid prevails and will thus provide a self-reciprocating spool shifting action without aid of external operators such as solenoids, motors or other source of powerrlt is also obvious that the change of working fluid pressures supplied to this device will either speed up the reciprocating action or slow it down and that as such will provide a self-regulating mode of operation, satisfying conditions set forth by this invention. Further, it is obvious too that the operation of this pump depends on a single control element, such as a simple flow regulator on the infeed line to control fluid pressures, and a simple shutoff valve for system start and stop function, satisfying simplicity parameters entailed in this invention. 1
Shown in FIGS. 2a and 2b are arrangements similar to those identified in FIGS. la and lb with exception of housing 30 which includes additional ports for fluid flow as required by a typical four-way valve in which spool shifting opens additional exhaust ports 43 and 44 for cylinder one" and cylinder two exhaust respectfully. The spool configuration here is identical to the spool configuration described when discussing FIGS. la and lb. Also the operation of the device in a fourway valve envelop is identical in terms of pressure forces act ing upon pistons and shifting spool to either cylinder one feeding port 33 while cylinder two port 41 is exhausting via cylinder two exhaust port 44, or vice versa, and will need no further discussion. The components shown in FIG. 2a and 2 are as follows:
valve housing 30 having a continuous central bore 31 symmetrically bored to receive slidably a symmetrical spool 32 with two opposing large diameter pistons 6 and tie at each spool end and a smaller piston 40 situated midway for entering into the large housing bores 33a and 33b and a smaller middle bore 34. At the extreme end of each large diameter bore provisions are made by means of grooves 36 and 36a to receive truarc rings 35 and 35a which serve as spool stops and provide an easy spool installation and maintenance means.
The valve housing is provided with fluid infeed port 37 which terminates with orifice 37a in direct communication with housing bore 34 serving annulus 38 to feed cylinder one" port 39 in FIG. 2a and also serving annulus 50 to feed cylinder two port 41 in FIG. 2b.
Seals 42, 42a and 42b of O-ring configuration or the like and of appropriate size serve as positive sealing means during the axial spool sliding and change of spool position during the valve operation.
Ports 44 and 43 serve as cylinder exhaust means. FIG. 2a shows cylinder one being energized by the working fluid flowing from port 37 via orifice 37a and annulus 38 into port 39 while the cylinder two at port 41 is to exhaust via port 44, and the seals 42 and 42b seal off the communications with other than ports 37 and 39. FIG. 2b shows spool 32 shifted and cylinder one exhausting from cylinder one port 39 via bore 43a and cylinder one" exhaust port 43 while the cylinder two" at port 41 is feeding via annulus 50 in direct communication with infeed port 37. The position change and cylinder feeding and exhaust in a continuous self-regulated reciprocating action of the spool will continue for as long as the pressurized fluid enters port 37 to act upon the pistons 6 and 6a of this valve.
The invention is not restricted to the slavish imitation of each and every one of the details described above which have been set forth merely by way of example with the intent of most clearly setting forth the teachings of the'invention. Obvi' ously, devices may be provided which change, eliminate, add certain specific structural details without departing from the invention.
lclaim:
l. A spool valve device including means defining a bore having a relatively small-diameter central portion and relatively large-diameter end portions, a spool received for reciprocation in said bore, said spool having a relatively small-diameter upon by fluid pressure between the inlet port and that outlet port which is not blocked by the central piston so as to shift the spool.
2. A device as in claim 1, including seals such as O-rings spaced from each other along the spool so that each is positioned to remain engaged with one of said pistons during the spool movement axially under all operating conditions.

Claims (2)

1. A spool valve device including means defining a bore having a relatively small-diameter central portion and relatively largediameter end portions, a spool received for reciprocation in said bore, said spool having a relatively small-diameter central the spool. and having relatively large-diameter end pistons, said pistons being slidable in the corresponding bore portions, a centrally located inlet port to the bore, at least two outlet ports spaced along the bore on opposite sides of the inlet port, the central small-diameter piston being arranged to alternately block flow between the inlet port and each of said two outlet ports as the spool reciprocates in the bore, each of the largediameter end pistons being arranged to be acted upon by fluid pressure between the inlet port and that outlet port which is not blocked by the central piston so as to shift the spool.
2. A device as in claim 1, including seals such as O-rings spaced from each other along the spool so that each is positioned to remain engaged with one of said pistons during the spool movement axially under all operating conditions.
US3570523D 1969-07-16 1969-07-16 Self-regulating reciprocator device Expired - Lifetime US3570523A (en)

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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3752399A (en) * 1970-08-31 1973-08-14 Rene Andre Louis Moulard Apparatus for treating human hair
US4056123A (en) * 1973-09-26 1977-11-01 Nihon Spindle Seizo Kabushiki Kaisha Hydraulic oscillator
US4265269A (en) * 1979-04-09 1981-05-05 Dolberg Vladimir I Device for automatically cutting off damaged branches of pneumatic and hydraulic systems
US4441629A (en) * 1982-08-10 1984-04-10 Mackal Glenn H Compressed gas powered caulking gun
US5775359A (en) * 1993-07-07 1998-07-07 Mannesmann Ag Hydraulic pressure control valve, especially a hydraulic power brake valve
US20060075989A1 (en) * 2004-04-30 2006-04-13 Vanderbilt University High efficiency hot gas vane actuator
US8474480B1 (en) * 2010-06-03 2013-07-02 Bs&B Safety Systems Limited Actuator control valve

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3326236A (en) * 1964-06-24 1967-06-20 Beckett Harcum Company Magnetically detented valve and method of adjustment

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3326236A (en) * 1964-06-24 1967-06-20 Beckett Harcum Company Magnetically detented valve and method of adjustment

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3752399A (en) * 1970-08-31 1973-08-14 Rene Andre Louis Moulard Apparatus for treating human hair
US4056123A (en) * 1973-09-26 1977-11-01 Nihon Spindle Seizo Kabushiki Kaisha Hydraulic oscillator
US4265269A (en) * 1979-04-09 1981-05-05 Dolberg Vladimir I Device for automatically cutting off damaged branches of pneumatic and hydraulic systems
US4441629A (en) * 1982-08-10 1984-04-10 Mackal Glenn H Compressed gas powered caulking gun
US5775359A (en) * 1993-07-07 1998-07-07 Mannesmann Ag Hydraulic pressure control valve, especially a hydraulic power brake valve
US20060075989A1 (en) * 2004-04-30 2006-04-13 Vanderbilt University High efficiency hot gas vane actuator
US8474480B1 (en) * 2010-06-03 2013-07-02 Bs&B Safety Systems Limited Actuator control valve

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