US3186173A - Variable pressure hydraulic system - Google Patents

Variable pressure hydraulic system Download PDF

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US3186173A
US3186173A US56165A US5616560A US3186173A US 3186173 A US3186173 A US 3186173A US 56165 A US56165 A US 56165A US 5616560 A US5616560 A US 5616560A US 3186173 A US3186173 A US 3186173A
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pressure
cylinder
hydraulic
piston
valve
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US56165A
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Hogg Stanley Thomas
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AMF Inc
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AMF Inc
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/028—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force
    • F15B11/032—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force by means of fluid-pressure converters
    • F15B11/0325—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the actuating force by means of fluid-pressure converters the fluid-pressure converter increasing the working force after an approach stroke
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B3/00—Intensifiers or fluid-pressure converters, e.g. pressure exchangers; Conveying pressure from one fluid system to another, without contact between the fluids
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20538—Type of pump constant capacity
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/21—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge
    • F15B2211/214—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being hydrotransformers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/32—Directional control characterised by the type of actuation
    • F15B2211/321—Directional control characterised by the type of actuation mechanically
    • F15B2211/324—Directional control characterised by the type of actuation mechanically manually, e.g. by using a lever or pedal
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40515—Flow control characterised by the type of flow control means or valve with variable throttles or orifices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40576—Assemblies of multiple valves
    • F15B2211/40584—Assemblies of multiple valves the flow control means arranged in parallel with a check valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41527—Flow control characterised by the connections of the flow control means in the circuit being connected to an output member and a directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/45—Control of bleed-off flow, e.g. control of bypass flow to the return line
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/47—Flow control in one direction only
    • F15B2211/473—Flow control in one direction only without restriction in the reverse direction
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7051—Linear output members
    • F15B2211/7052—Single-acting output members
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/77—Control of direction of movement of the output member
    • F15B2211/7716—Control of direction of movement of the output member with automatic return

Definitions

  • This invention relates in general to hydraulic systems and, more particularly, to hydraulic systems wherein the pressure may be variedover a wide range.
  • An object of this invention is to provide a hydraulic system which is capable of more versatile operation from a constant in'put pressure source. 7
  • Another object of this invention is to provide a hydraulic system having aworking cylinder and a pressure intensification cylinder in which an infinite variety of pressures up to the maximum pressure produced by the pressure intensification cylinder may be applied to the working cylinder.
  • a further object of this invention is to provide a simple pressure intensification system which may be used in connection with a hydraulic work producing device to increase the force which may be applied by the work producing device.
  • a still further object of this invention is to provide a hydraulic system in which a given pressure source and a given work cylinder may be used to apply a greater working force.
  • Still another object of this invention is to provide a hydraulic system which is simple in its construction and which requires fewer hydraulic connections to apply a wider range of pressures to a hydraulically operated device.
  • Yet another object of this invention is toprovide a hydraulic system to activate a work cylinder and move its piston rapidly against little or no resisting force and in which the work cylinder may be further activated by the hydraulic system to move more slowly and apply a larger force.
  • the single figure of the drawing is a schematic illustra tion of the invention with the work cylinder and the pressure intensification cylinder shown in longitudinal crosssection.
  • a pipe, tube, hose or the like is designated by the reference numeral 33 and is connected to a source of hydraulic fluid under pressure.
  • the source of hydraulic pressure may b'ea pump 41 which draws hydraulic fluid 37 from the sump 36 through the tube 42, or the source of hydraulic pressure maybe a manifold which supplies hydraulic fluid under pressure to other devices on an existing machine. On one particular machine a manifold pressure of 250 pounds is applied to pipe 33 as this pressure operates other mechanisms and therefore cannot be varied.
  • the pressure regulating valve or controlled pressure drop valve 30 allows hydraulic fluid to pass through it until the pressure for which the valve 30 is set builds up in pipe 27 to the pressure for which the pre-set valve 34 is set.
  • a pipe 29 bypasses the controlled pressure drop valve 30, but the higher pressure in pipe 32 cannot flow about the controlled pressure drop valve 30 through the bypass 29 because the check valve 28 blocks it.
  • the hydraulic fluid at the selected lower pressure which passes through the controlled pressure drop valve 30 flows through pipe 27 and through the port 40 in the smaller end 19 of the pressure intensification cylinder which is generally designated by the numeral 60.
  • the force exerted on the work pieces 29 by the jaws 11 and 12 will be determined bythe area of the piston'face of piston 15 and the pressure which the pressure regulating valve 30 is set to pass.
  • valve 30 By varying the setting of valve 30 from zero to the pressure available from the hydraulic pressure source, a range of forces may be applied to jaw 12 by the work cylinder 50.
  • the line valve 26 When it is desired to apply greater force on work pieces 20 by jaw 12, the line valve 26 is opened allowing hydraulic fluid to flow behind piston 22 within the large portion 18 of the pressure intensification cylinder 61].
  • the larger area of the piston face of piston 22 compared to the piston face of the pressure intensification piston 23 causes the pistons 22 and 23 to move to the left as shown in the drawing. As piston 23 moves to the left, it passes the port 40 and effectively closes it so that hydraulic fluid cannot flow from the smaller portion 19 of the pressure intensification cylinders!) back down pipe 27.
  • valve 34 urges piston 22 to the right forcing fluid within the large portion 18 of pres sure intensification cylinder 60 to flow out through pipe 25
  • valve 34 is again set to connect pipes 33 and 32 whereupon the cycle may be repeated. It is to be noted that if the valve 26 is left closed, the regulating valve 30 may be used to directly control the hydraulic pressure Within the work cylinder 50 and the force exerted by jaw 12 on the work pieces 20.
  • an existing machine has a work cylinder or other hydraulic device activated from a source of hydraulic fluid under pressure through a controlled pressure drop valve to vary the force exerted by the work cylinder
  • a relatively simple modification of an existing machine according to this invention may increase the force exerted by the work cylinder by any desired multiple.
  • the pressure in the hydraulic manifold is of a constant value which cannot conveniently be changed for the reason that such machines have various other elements activated from the manifold.
  • This invention is readily adapted to such machines where it is desired to have a Wider range of clamping force on the work-holding fixture.
  • the invention may be readily adapted to existing machines as well as being easily built into new machines. If this invention is applied to an existing machine, the machines hydraulic system need not be affected as the machine may be conventionally operated without activating the pressure intensification cylinder.
  • valve 30 with the pressure intensification cylinder 60 permits an infinite selection of pressure values to the work pistion 15 from zero to a value equal to the product of the value of the pressure source by the pressure intensification cylinder multiple. Pressures less than the pressure source may be obtained by closing the valve 26 so that the pressure intensification cylinder is bypassed. Pressures above the source pressure may be obtained by opening the valve 26 and suitably adjusting the valve 30.
  • the spring 24 should be set to counter-balance piston 22 to resist a hydraulic force greater than the hydraulic force on piston 15 resisted by spring 16. This assures that the port 40 will not be closed until the jaw 12 has contacted the workpiece.
  • a reservoir for hydraulic fluid said reservoir connected through a source of hydraulic fluid under pressure, a controlled pressure drop mechanism in a line from the source of hydraulic fluid under pressure, a two way valve which in a first position connects the controlled pressure drop mechanism to the source of hydraulic fluid under pressure and in a second position communicates the controlled pressure drop mechanism with the reservoir, a check valve connected across the controlled pressure drop mechanism to permit flow only from the outlet of the controlled pressure drop mechanism to the inlet thereof, said two way valve thus being operable to selectively direct fluid from said source of hydraulic fluid under pressure toward said controlled pressure drop valve and from said check valve to said reservoir, a pressure intensification cylinder having a larger portion and a smaller portion, a piston having a larger portion and a smaller portion reciprocable in said larger portion and said smaller portion of said cylinder, respectively, the smaller portion of the cylinder having a side port, a spring in the pressure intensification cylinder biasing the piston to its retracted position, a first conduit communicating the pressure drop mechanism to the side port, said port being in communication

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Description

June 1, 1965 s. 'r. HOGG 3,186,173
VARIABLE PRES SURE I HYDRAULI C SYS TEM Filed Sept. 15. 1960 INVENTOR. Stanley T. Hogg ATTORNEY United States Patent C 3,186,173 VARIABLE PRESSURE HYDRAULIC SYSTEM Stanley Thomas Hogg, Merrick, N.Y., assignor to American Machine & Foundry Company, a corporation of New Jersey Filed Sept. 15, 1960, Ser. No. 56,165
1 Claim. (Cl. '60---54.5)
This invention relates in general to hydraulic systems and, more particularly, to hydraulic systems wherein the pressure may be variedover a wide range.
An object of this invention is to provide a hydraulic system which is capable of more versatile operation from a constant in'put pressure source. 7
Another object of this invention is to provide a hydraulic system having aworking cylinder and a pressure intensification cylinder in which an infinite variety of pressures up to the maximum pressure produced by the pressure intensification cylinder may be applied to the working cylinder.
A further object of this invention is to provide a simple pressure intensification system which may be used in connection with a hydraulic work producing device to increase the force which may be applied by the work producing device.
A still further object of this invention is to provide a hydraulic system in which a given pressure source and a given work cylinder may be used to apply a greater working force.
Still another object of this invention is to provide a hydraulic system which is simple in its construction and which requires fewer hydraulic connections to apply a wider range of pressures to a hydraulically operated device.
Yet another object of this invention is toprovide a hydraulic system to activate a work cylinder and move its piston rapidly against little or no resisting force and in which the work cylinder may be further activated by the hydraulic system to move more slowly and apply a larger force.
Additional objects, advantages and features of invention reside in the construction, arrangement and combination The hydraulic fluidthen flows through the smaller end 19 of the pressure intensification cylinder 60 and then through pipe 17 into a work cylinder generally designated on the piston rod 13 to urge jaw 12 towards the fixed jaw 11. Therefore, as shown in the drawing, when pressure of parts involved in the embodiment of the invention and its practice as will be understood from the following description and accompanying drawing wherein:
The single figure of the drawing is a schematic illustra tion of the invention with the work cylinder and the pressure intensification cylinder shown in longitudinal crosssection.
Referring to the drawing in detail, a pipe, tube, hose or the like is designated by the reference numeral 33 and is connected to a source of hydraulic fluid under pressure. The source of hydraulic pressure may b'ea pump 41 which draws hydraulic fluid 37 from the sump 36 through the tube 42, or the source of hydraulic pressure maybe a manifold which supplies hydraulic fluid under pressure to other devices on an existing machine. On one particular machine a manifold pressure of 250 pounds is applied to pipe 33 as this pressure operates other mechanisms and therefore cannot be varied. When the two-way valve 34 is turned so that hydraulic fluid under pressure may flow from pipe 33 into pipe 32, the pressure regulating valve or controlled pressure drop valve 30 allows hydraulic fluid to pass through it until the pressure for which the valve 30 is set builds up in pipe 27 to the pressure for which the pre-set valve 34 is set. A pipe 29 bypasses the controlled pressure drop valve 30, but the higher pressure in pipe 32 cannot flow about the controlled pressure drop valve 30 through the bypass 29 because the check valve 28 blocks it. The hydraulic fluid at the selected lower pressure which passes through the controlled pressure drop valve 30 flows through pipe 27 and through the port 40 in the smaller end 19 of the pressure intensification cylinder which is generally designated by the numeral 60.
from a hydraulic pressure source flows through pipe 33 and past valve 30 with a controlled pressure into the work cylinder 50, the hydraulic fluid at a selected pressure will urge the piston '15 to the right so that the work pieces 26 will be held between the jaws 11 and 12. If the source of hydraulic pressure which is connected to pipe 33, such as pump 41, can only deliver a given number of cubic inches of hydraulic fluid per second at a given-pressure, a relatively small diameter work cylinder 5%) will more rapidly move jaw 12 towards jaw 11 to grip the work pieces 20.
When the work pieces 20 are clamped between the jaws 11 and 12 as shown in the drawing, the force exerted on the work pieces 29 by the jaws 11 and 12 will be determined bythe area of the piston'face of piston 15 and the pressure which the pressure regulating valve 30 is set to pass. By varying the setting of valve 30 from zero to the pressure available from the hydraulic pressure source, a range of forces may be applied to jaw 12 by the work cylinder 50.
When it is desired to apply greater force on work pieces 20 by jaw 12, the line valve 26 is opened allowing hydraulic fluid to flow behind piston 22 within the large portion 18 of the pressure intensification cylinder 61]. The larger area of the piston face of piston 22 compared to the piston face of the pressure intensification piston 23 causes the pistons 22 and 23 to move to the left as shown in the drawing. As piston 23 moves to the left, it passes the port 40 and effectively closes it so that hydraulic fluid cannot flow from the smaller portion 19 of the pressure intensification cylinders!) back down pipe 27. As additional hydraulic fluid at a controlled pressure flows past valve 30 and valve 26 through pipe 25 into the pressure intensification cylinder 60, the pressure in the smaller portion 19 of the pressure intensification cylinder becomes a multiple of the pressure passed by pressure regulating valve 30 and exerted on the larger piston 22. The multiple by which the pressure intensification'cylinder increases the pressure is determined by the ratio of the areas of the piston faces of piston 22 and the pressure intensification piston 23. As the pressure intensification piston 23 moves further to the left as shown in the drawing, hydraulic fluid under this intensified pressure flows through pipe 17 to exert a correspondingly increased pressure on piston 15. The increased pressure on piston 15 increases the force exerted on the movable jaw 12 which then more tightly clamps the work pieces 20.
After a desired operation is performed on the work pieces 20 while they are clamped between the jaws 11 and 12, the two-way valve 34 is turned so that pipe 32 is connected to drain pipe 35 which leads to the sump 36 which catches hydrauluic fluid 37 draining from the system. When pipe 32 is connected to drain '35, pressure in pipe 32 falls to Zero. Within the work cylinder 50 a compression spring 16 is constantly urging piston 15 to the left. In a like manner, a spring 24 in the pressure intensification cylinder 69 is constantly urging the pistons 22 and 23 to the right. The spring 24 urges piston 22 to the right forcing fluid within the large portion 18 of pres sure intensification cylinder 60 to flow out through pipe 25 When it is again desired to activate work cylinder 50 i and close jaws 11 and 12, valve 34 is again set to connect pipes 33 and 32 whereupon the cycle may be repeated. It is to be noted that if the valve 26 is left closed, the regulating valve 30 may be used to directly control the hydraulic pressure Within the work cylinder 50 and the force exerted by jaw 12 on the work pieces 20.
If an existing machine has a work cylinder or other hydraulic device activated from a source of hydraulic fluid under pressure through a controlled pressure drop valve to vary the force exerted by the work cylinder, a relatively simple modification of an existing machine according to this invention may increase the force exerted by the work cylinder by any desired multiple. For example, in certain cut-off machines on the market having a work-holding fixture actuated by hydraulic pressure, supplied from a hydraulic source through a manifold, the pressure in the hydraulic manifold is of a constant value which cannot conveniently be changed for the reason that such machines have various other elements activated from the manifold. This invention is readily adapted to such machines where it is desired to have a Wider range of clamping force on the work-holding fixture.
Thus the invention may be readily adapted to existing machines as well as being easily built into new machines. If this invention is applied to an existing machine, the machines hydraulic system need not be affected as the machine may be conventionally operated without activating the pressure intensification cylinder.
The arrangement of the valve 30 with the pressure intensification cylinder 60 permits an infinite selection of pressure values to the work pistion 15 from zero to a value equal to the product of the value of the pressure source by the pressure intensification cylinder multiple. Pressures less than the pressure source may be obtained by closing the valve 26 so that the pressure intensification cylinder is bypassed. Pressures above the source pressure may be obtained by opening the valve 26 and suitably adjusting the valve 30.
The spring 24 should be set to counter-balance piston 22 to resist a hydraulic force greater than the hydraulic force on piston 15 resisted by spring 16. This assures that the port 40 will not be closed until the jaw 12 has contacted the workpiece.
Although a work piece holding device is shown being activated by the work cylinder 50, this invention may be used for many other purposes.
While I have disclosed my invention in the best form known to me, it is to be understood that this is purely 4 exemplary and that modifications in the construction, arrangement and combination of parts and the substitution of equivalents mechanically and otherwise may be made without departing from the spirit of the invention except as it may be limited in the appended claim.
I claim:
In a hydraulic system, a reservoir for hydraulic fluid, said reservoir connected through a source of hydraulic fluid under pressure, a controlled pressure drop mechanism in a line from the source of hydraulic fluid under pressure, a two way valve which in a first position connects the controlled pressure drop mechanism to the source of hydraulic fluid under pressure and in a second position communicates the controlled pressure drop mechanism with the reservoir, a check valve connected across the controlled pressure drop mechanism to permit flow only from the outlet of the controlled pressure drop mechanism to the inlet thereof, said two way valve thus being operable to selectively direct fluid from said source of hydraulic fluid under pressure toward said controlled pressure drop valve and from said check valve to said reservoir, a pressure intensification cylinder having a larger portion and a smaller portion, a piston having a larger portion and a smaller portion reciprocable in said larger portion and said smaller portion of said cylinder, respectively, the smaller portion of the cylinder having a side port, a spring in the pressure intensification cylinder biasing the piston to its retracted position, a first conduit communicating the pressure drop mechanism to the side port, said port being in communication with the working chamber of the intensification cylinder when the piston is in the retracted position, and a second conduit communication the pressure drop mechanism to the larger portion of the pressure intensification cylinder, a valve in said second conduit, a hydraulic motor having a piston therein, said motor communicating with the smaller portion of said pressure intensification cylinder, and means normally biasing the piston in said hydraulic motor to its inactive position.
References Cited by the Examiner UNITED STATES PATENTS 1,888,990 11/32 Kurath -545 2,032,185 2/36 Sciaky 60-545 2,102,865 12/37 Vickers 60-52 2,286,620 6/42 Hollengreen 6097 X 2,403,912 7/46 D011 60-545 2,580,353 12/51 Hunt 60-545 2,656,745 10/53 Forichon 60 54.5
FOREIGN PATENTS 704,657 4/41 Germany.
JULIUS E. WEST, Primary Examiner.
SAMUEL LEVINE, ROBERT R. BUNEVICH,
Ex mi
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Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3382669A (en) * 1966-05-25 1968-05-14 Burndy Corp Hydraulic booster apparatus
US3583282A (en) * 1969-09-11 1971-06-08 Morgen Mfg Co Hydraulic system
US3942325A (en) * 1972-05-10 1976-03-09 David Franklin Howeth Hydraulic throttle actuator
US4570913A (en) * 1984-01-11 1986-02-18 Production Equipment & Engineering Co. Clamping apparatus for truss manufacturing equipment
US4620419A (en) * 1984-05-11 1986-11-04 Enfo Grundlagenforschungs Ag Hydraulic cylinder with power-multiplication
US4844431A (en) * 1988-06-29 1989-07-04 Arkansas Lousisiana Gas Company Pneumatic gas meter test fixture
WO1996001953A1 (en) * 1993-07-06 1996-01-25 Bertil Borg Automatic pressure booster device
US5662316A (en) * 1993-07-22 1997-09-02 Automation Enhancements Un Limited Pallet couple and decouple clamping apparatus and method for pallet coupling and decoupling
US6925916B2 (en) * 2000-03-03 2005-08-09 Pcps Limited Partnership Two stage punch press actuator with output drive shaft position sensing
US20050268461A1 (en) * 2004-06-07 2005-12-08 Ouellette Randall M Method and apparatus for securing turbine components for manufacture
US20210301839A1 (en) * 2020-03-27 2021-09-30 Smc Corporation Pressure-booster output stabilizer

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1888990A (en) * 1929-08-16 1932-11-29 Economy Fuse And Mfg Co Automatically controlled hydraulic press intensifier
US2032185A (en) * 1934-04-20 1936-02-25 Sciaky David Transmission system for a pressureoperated member such as a hydraulic press
US2102865A (en) * 1934-06-20 1937-12-21 Vickers Inc Combined flow control and relief valve
DE704657C (en) * 1937-03-10 1941-04-03 Hugo Miebach Hydraulic clamping device with circulation pump
US2286620A (en) * 1939-05-18 1942-06-16 Landis Tool Co Steady rest adjusting means
US2403912A (en) * 1944-01-17 1946-07-16 Link Engineering Co Press operating device
US2580353A (en) * 1947-11-08 1951-12-25 C B Hunt & Son Inc Fluid pressure intensifier
US2656745A (en) * 1946-05-25 1953-10-27 Forichon Gaston Sebastien Hydraulic system for riveting presses

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1888990A (en) * 1929-08-16 1932-11-29 Economy Fuse And Mfg Co Automatically controlled hydraulic press intensifier
US2032185A (en) * 1934-04-20 1936-02-25 Sciaky David Transmission system for a pressureoperated member such as a hydraulic press
US2102865A (en) * 1934-06-20 1937-12-21 Vickers Inc Combined flow control and relief valve
DE704657C (en) * 1937-03-10 1941-04-03 Hugo Miebach Hydraulic clamping device with circulation pump
US2286620A (en) * 1939-05-18 1942-06-16 Landis Tool Co Steady rest adjusting means
US2403912A (en) * 1944-01-17 1946-07-16 Link Engineering Co Press operating device
US2656745A (en) * 1946-05-25 1953-10-27 Forichon Gaston Sebastien Hydraulic system for riveting presses
US2580353A (en) * 1947-11-08 1951-12-25 C B Hunt & Son Inc Fluid pressure intensifier

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3382669A (en) * 1966-05-25 1968-05-14 Burndy Corp Hydraulic booster apparatus
US3583282A (en) * 1969-09-11 1971-06-08 Morgen Mfg Co Hydraulic system
US3942325A (en) * 1972-05-10 1976-03-09 David Franklin Howeth Hydraulic throttle actuator
US4570913A (en) * 1984-01-11 1986-02-18 Production Equipment & Engineering Co. Clamping apparatus for truss manufacturing equipment
US4620419A (en) * 1984-05-11 1986-11-04 Enfo Grundlagenforschungs Ag Hydraulic cylinder with power-multiplication
US4844431A (en) * 1988-06-29 1989-07-04 Arkansas Lousisiana Gas Company Pneumatic gas meter test fixture
WO1996001953A1 (en) * 1993-07-06 1996-01-25 Bertil Borg Automatic pressure booster device
US5662316A (en) * 1993-07-22 1997-09-02 Automation Enhancements Un Limited Pallet couple and decouple clamping apparatus and method for pallet coupling and decoupling
US5794324A (en) * 1993-07-22 1998-08-18 Automation Enhancements Unlimited Pallet couple and decouple clamping apparatus and method for pallet coupling and decoupling
US6022007A (en) * 1993-07-22 2000-02-08 Automation Enhancements Un Limited Pallet couple and decouple clamping apparatus
US6925916B2 (en) * 2000-03-03 2005-08-09 Pcps Limited Partnership Two stage punch press actuator with output drive shaft position sensing
US20050268461A1 (en) * 2004-06-07 2005-12-08 Ouellette Randall M Method and apparatus for securing turbine components for manufacture
US20210301839A1 (en) * 2020-03-27 2021-09-30 Smc Corporation Pressure-booster output stabilizer
US11661960B2 (en) * 2020-03-27 2023-05-30 Smc Corporation Pressure-booster output stabilizer

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