US3661179A - Automatic oil pressure switch valve - Google Patents

Automatic oil pressure switch valve Download PDF

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Publication number
US3661179A
US3661179A US44750A US3661179DA US3661179A US 3661179 A US3661179 A US 3661179A US 44750 A US44750 A US 44750A US 3661179D A US3661179D A US 3661179DA US 3661179 A US3661179 A US 3661179A
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US
United States
Prior art keywords
oil
passage
valve
switch
pressure relief
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US44750A
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English (en)
Inventor
Kingo Hasumi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sanwa Tekki Corp
Original Assignee
Sanwa Tekki Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sanwa Tekki Corp filed Critical Sanwa Tekki Corp
Application granted granted Critical
Publication of US3661179A publication Critical patent/US3661179A/en
Anticipated expiration legal-status Critical
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
    • F16K11/00—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves
    • F16K11/10—Multiple-way valves, e.g. mixing valves; Pipe fittings incorporating such valves with two or more closure members not moving as a unit
    • 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
    • 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
    • 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
    • F15B2211/212—Systems with pressure sources other than pumps, e.g. with a pyrotechnical charge the pressure sources being accumulators
    • 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
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40507—Flow control characterised by the type of flow control means or valve with constant 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
    • F15B2211/50—Pressure control
    • F15B2211/505—Pressure control characterised by the type of pressure control means
    • F15B2211/50509—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means
    • F15B2211/50518—Pressure control characterised by the type of pressure control means the pressure control means controlling a pressure upstream of the pressure control means using pressure relief valves
    • 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
    • F15B2211/50—Pressure control
    • F15B2211/515—Pressure control characterised by the connections of the pressure control means in the circuit
    • F15B2211/5151—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source 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
    • F15B2211/50—Pressure control
    • F15B2211/55—Pressure control for limiting a pressure up to a maximum pressure, e.g. by using a pressure relief 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/625—Accumulators
    • 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/635—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements
    • F15B2211/6355—Circuits providing pilot pressure to pilot pressure-controlled fluid circuit elements having valve means
    • 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
    • F15B2211/76—Control of force or torque of the output member
    • 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
    • F15B2211/7725—Control of direction of movement of the output member with automatic reciprocation
    • Y—GENERAL 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87169—Supply and exhaust
    • Y10T137/87177—With bypass

Definitions

  • ABSTRACT An automatic oil pressure switch valve adapted to an oil supply system and being operative by pushing merely the switch for regulating an electro-magnetic switch valve whereby an oil pressure press is actuated and when a desired pressure is attained, a ram is moved backward to stop the press so that only a pushing of the switch is sufficient each time to fix the means being handled and hence there occurs no excessive strain on the switch valve to actuate so that such component will not easily break down.
  • a pilot pressure is regulated by being introduced into a low pressure passage from an extaordinarily high pressure pump whereby a satisfactory precision of regulation is possible without employing a special electro-magnet and pressure switch.
  • the present invention relates to an automatic switch valve operated by low oil pressure adapted to an oil supply system having a single acting pressure rarn wherein the valve can be automatically switched by low oil pressure when the pressure of flowing oil against the press reaches a desired high value, so as to cause the flow of oil to the press to stop and the pressure to lower.
  • the object of the present invention is to provide a new and improved switch valve operated automatically by oil pressure, especially used for controlling such extraordinarily high oil pressure as 500-1 ,OOOkg/cm.
  • An automatic oil pressure switch valve having a single acting press ram by which a spool valve of a main cylinder is actuated to move in alternate directions by switching an electromagnetic switch valve arranged in a low pressure relief passage communicating with a space at one end of a pilot piston of a switch cylinder via an electric switch valve, a check valve and a low pressure relief valve leading to one of a plurality of annular grooves provided for the main cylinder.
  • the main cylinder has a spool valve slidably positioned therein and spring biased at one end thereof, with the cylinder having a plurality of axially spaced annular grooves.
  • One of the grooves via a receiving passage, communicates with an oil pressure pump, another of the grooves communicates with a low pressure relief passage, another of the grooves via a delivery passage communicates with an oil pressure press and the last groove through an exhaust oil passage with an exhaust oil pipe, with the reciprocation of the spool valve forcing oil flow into the delivery passage or the low pressure relief passage, selectively.
  • the switch cylinder has slidably mounted therein a pilot piston which is spring biased at one end with the space around the spring being in communication with an exhaust oil passage leading to the exhaust oil pipe, and a second space at the opposite end piston being opened to the low pressure relief passage and a check valve adjacent the spring at the front face of the pilot piston being capable of opening and closing by the reciprocation of such pilot piston.
  • FIG. 1 is an elevational cross-sectional view of the device contemplated herein;
  • FIG. 2 is a view in cross section and partly in elevation of the spool valve in the main cylinder of FIG. 1 in its retracted position or with the spring compressed.
  • a new and improved switch valve having housings 2 and 3 on opposite sides of a body 1 fixed integrally therewith, comprising a main cylinder 4, a switch cylinder 5, a relief passage 6 for high pressure, a switch passage 7 and a relief passage 8 for low pressure.
  • a spool type valve 9 having axially spaced lands 9a, 9b, 9c of different lengths.
  • a coil spring 10 surrounds extension 9d of the valve 9 and is biased between the base of the cylinder 4 and the end face of the land 9c to nonnally displace the valve to the position shown in FIG. 1.
  • Axially spaced annular grooves 40, 4b, 4c and 4d communicate with the cylinder 4.
  • the groove 4c communicates, via a delivery passage 11, with an oil pressure press R and the groove 44 with a low pressure relief passage 8.
  • the slot 4b via receiving passage 12, communicates with an oil pressure pump P and the slot 4d through an exhaust oil passage 17 with an exhaust oil pipe (not shown) which leads to an oil tank T.
  • the pump 12 delivers pressure oil selectively through passage 12 by reciprocation of the valve 9 to either be delivered to passage 9 or the low pressure relief passage 8.
  • the land 9b prevents flow from the passage 12 to the passage 8 but allows flow via groove 4b, cylinder 4, groove 40 and delivery passage 11 to the press R.
  • the valve 9 is in the position shown in FIG. 2, oil flow is permitted through receiving passage 12, groove 4b, cylinder 4, and groove 40 to the relief passage 8 with the land 9b blocking flow to the groove 4c and delivery passage 11.
  • the switch cylinder 5 has a pilot piston 13 slidably located therein, with a spring 14 biased between one end wall of the cylinder 5 and a face of the piston 13 and at the other end is supported by the face of the piston 13 of a rod 15 having a manipulating handle with the rod being threaded into the housing 3.
  • a check valve 16 consisting of a ball seat 16a, a ball 16b and a spring is provided at the left in the drawing (hereinafter referred to front of the pilot piston 13, which valve is opened or closed according to the reciprocation of the pilot piston 13 or of the rod 15 which is usually kept rearward to maintain the valve closed.
  • the check valve 16 controls passage 70 located between the switch passage 7 and the cylinder 5, and it will be noted that the piston 13 is provided with an extension 13a which, when the piston 13 is displaced towards the left (FIG. 1) will remove the ball 16b from the seat 16a thereby providing communication between the switch passage 7 and the cylinder 5.
  • An exhaust oil passage 17a opens in a space 17b of the pilot piston 13 and communicates with the oil tank (T) through the exhaust oil pipe and a space to the rear of the pilot piston 13 opens into the end of the low pressure relief passage 8.
  • the high pressure relief passage 6 which branches from the delivery passage 12, communicates with the space around the spring 10 through a throttle valve 18, and via another branch with the oil exhaust pipe through the high pressure relief valve (H).
  • the low pressure relief passage 8 which opens into the groove 40 of the cylinder 4 communicates with the space to the rear of the pilot piston 13 through a low pressure relief valve (L), a check valve 20 and an electro-magnetic switch valve 21 of a solenoid type which changes the oil flow of the low pressure relief passage 8 by closing or opening the solenoid switch.
  • the switch passage 7 and the low pressure passage 8 are provided with accumlators 22 and 23 respectively for facilitating action of the parts which are influenced by the oil pressure moving through the open passage, of which pressure is forced by a step plate biased with the spring when the oil pressure at the passage is in a desired pressure.
  • oil is delivered through the receiving passage 12, the grooves 4b and 4c and the delivering passage 11 into the oil pressure press (R), while the check valve 16 and the switch passage 7 are shut and while the groove 40 is being shut by the the land 9b of the valve 9, the low pressure relief passage 8 is also closed.
  • the high pressure relief valve (H) is opened, and at the same time the oil pressure in the spring chamber of the spool valve 9 comes down by the action of the throttle valve 18, and the spool valve 9 slides rearward as shown in FIG. 2 smoothly facilitated by the accumulator 22, after which the oil in the oil pressure press (R) flows back into the oil tank (T) through the delivery passage 11 in a reverse manner and through the grooves 4c and 4a.
  • the oil in the receiving passage 12 flows away into the tank (T) through the groove 4a, the low pressure relief valve (L), the check valve and the electro-magnetic switch valve 21.
  • the low pressure relief passage 8 is opened by depressing the electro-magnetic switch valve 21 to shift the valve.
  • the spool valve 9 moves forward as shown in FIG. 1, while low pressure oil flows into the rear space of the pilot piston 13 which is forced to open the check valve 16, being facilitated by the accumlator 23 which insures opening of the valve 16, whereby the switch passage 7 communicates with the exhaust oil passage 17 loosing the pressure therein so that the balance of pressure in both spaces is lost, whereby the spool valve 9 moves forward and oil is delivered to the oil pressure press (R) through the grooves slot 4b and 4c, and such operation as described above is repeated again and again.
  • the rod 15 is employed to operate the check valve 16 instead of the electromagnetic switch valve 21 for the purpose of checking every part.
  • the electro-magnetic switch valve is protected by the low pressure relief valve (L).
  • the construction and the operation of the present invention are such that the size and the weight of a device employing the present oil pressure switch valve can be manufactured sufficiently small and light in weight to transport, for an example, by those who work to connect wires on an electric pole where they carry only a portable single acting press and a switch for actuating the electro-magnetic switch valve set on the ground being connected with an oil pressure pump having the switch valve of this invention.
  • an automatic switch valve operated by low oil pressure adapted to an oil supply system having an oil pressure press in which the switch valve can be automatically switched by low oil pressure when the pressure of the flowing oil reaches a desired high value to cause the flow of oil to the ram to stop and the pressure to lower
  • a main cylinder a balancing piston positioned for reciprocation in the main cylinder, a spring within the main cylinder at one end of the piston, an oil pump, an exhaust oil conduit, an oil tank with which the exhaust oil conduit communicates, a switch cylinder, a pilot piston in the switch cylinder, said main cylinder having a plurality of axially spaced grooves, a first of said grooves communicating with the oil pump via a receiving passage, a second of said grooves being open to a low pressure relief passage, a third of said grooves communicating with the oil pressure press via a delivery passage, and a fourth of said grooves communicating with the exhaust oil conduit via an exhaust oil passage, the reciprocation of the balancing piston directing oil flow into the delivery passage or the low

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control Of Presses (AREA)
US44750A 1970-02-20 1970-06-09 Automatic oil pressure switch valve Expired - Lifetime US3661179A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP45014175A JPS499152B1 (enrdf_load_stackoverflow) 1970-02-20 1970-02-20

Publications (1)

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US3661179A true US3661179A (en) 1972-05-09

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Family Applications (1)

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US44750A Expired - Lifetime US3661179A (en) 1970-02-20 1970-06-09 Automatic oil pressure switch valve

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US (1) US3661179A (enrdf_load_stackoverflow)
JP (1) JPS499152B1 (enrdf_load_stackoverflow)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11009426B2 (en) * 2017-12-19 2021-05-18 Hyundai Motor Company Oil pressure switch, apparatus for diagnosing piston cooling oil jet, and method of controlling the same

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3395617A (en) * 1965-08-30 1968-08-06 Ford Motor Co Servo motor for positioning a valve as a function of engine load
US3439584A (en) * 1965-08-30 1969-04-22 Ford Motor Co Fluid pressure control system
US3524386A (en) * 1968-06-11 1970-08-18 Sylvester R Cudnohufsky Hydraulic system for machine tool control

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3395617A (en) * 1965-08-30 1968-08-06 Ford Motor Co Servo motor for positioning a valve as a function of engine load
US3439584A (en) * 1965-08-30 1969-04-22 Ford Motor Co Fluid pressure control system
US3524386A (en) * 1968-06-11 1970-08-18 Sylvester R Cudnohufsky Hydraulic system for machine tool control

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11009426B2 (en) * 2017-12-19 2021-05-18 Hyundai Motor Company Oil pressure switch, apparatus for diagnosing piston cooling oil jet, and method of controlling the same
US11467062B2 (en) 2017-12-19 2022-10-11 Hyundai Motor Company Oil pressure switch, apparatus for diagnosing piston cooling oil jet, and method of controlling the same

Also Published As

Publication number Publication date
JPS499152B1 (enrdf_load_stackoverflow) 1974-03-02

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