US3476017A - Power-limiting device for a machine provided with two or more working components - Google Patents

Power-limiting device for a machine provided with two or more working components Download PDF

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Publication number
US3476017A
US3476017A US627916A US3476017DA US3476017A US 3476017 A US3476017 A US 3476017A US 627916 A US627916 A US 627916A US 3476017D A US3476017D A US 3476017DA US 3476017 A US3476017 A US 3476017A
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pressure
hydraulic
fluid
jib
valve
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US627916A
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Knut Olov Frisk
Karl Paul Gustafsson
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TICO AB
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TICO AB
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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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C23/00—Cranes comprising essentially a beam, boom, or triangular structure acting as a cantilever and mounted for translatory of swinging movements in vertical or horizontal planes or a combination of such movements, e.g. jib-cranes, derricks, tower cranes
    • B66C23/88—Safety gear
    • B66C23/90—Devices for indicating or limiting lifting moment
    • 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
    • F15B2211/30505—Non-return valves, i.e. check 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
    • F15B2211/30—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
    • F15B2211/42—Flow control characterised by the type of actuation
    • F15B2211/428—Flow control characterised by the type of actuation actuated by fluid pressure
    • 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
    • F15B2211/50—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
    • F15B2211/5158—Pressure control characterised by the connections of the pressure control means in the circuit being connected to a pressure source and 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
    • F15B2211/50—Pressure control
    • F15B2211/52—Pressure control characterised by the type of actuation
    • F15B2211/521—Pressure control characterised by the type of actuation mechanically
    • F15B2211/522—Pressure control characterised by the type of actuation mechanically actuated by biasing means, e.g. spring-actuated
    • 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
    • F15B2211/52—Pressure control characterised by the type of actuation
    • F15B2211/528—Pressure control characterised by the type of actuation actuated by fluid pressure
    • 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
    • F15B2211/605—Load sensing circuits
    • F15B2211/6051—Load sensing circuits having valve means between output member and the load sensing circuit
    • 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
    • F15B2211/705—Output members, e.g. hydraulic motors or cylinders or control therefor characterised by the type of output members or actuators
    • F15B2211/7058—Rotary 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
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders
    • 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
    • F15B2211/80—Other types of control related to particular problems or conditions
    • F15B2211/875—Control measures for coping with failures
    • F15B2211/8752—Emergency operation mode, e.g. fail-safe operation mode
    • 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
    • Y10T137/2496—Self-proportioning or correlating systems
    • Y10T137/2559—Self-controlled branched flow systems
    • Y10T137/2574—Bypass or relief controlled by main line fluid condition
    • Y10T137/2605—Pressure responsive
    • Y10T137/2617—Bypass or relief valve biased open
    • 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
    • Y10T137/2496—Self-proportioning or correlating systems
    • Y10T137/2559—Self-controlled branched flow systems
    • Y10T137/2574—Bypass or relief controlled by main line fluid condition
    • Y10T137/2605—Pressure responsive
    • Y10T137/2635—Pilot valve operated

Definitions

  • FIG. 4 POWER-LIMITING DEVICE FOR A MACHINE PROVIDED WITH TWO OR MORE WORKING COMPONENTS 4 Sheets-Sheet 4 Filed April 5, 1967 FIG. 4
  • Pressure sensing means are provided in a hydraulic power circuit that can cut the supply of hydraulic power to all hydraulically operated actuators provided in the circuit in case of overload.
  • the pressure sensing means are capable of preventing overload at any desired pressure while maintaining sufficient hydraulic power to prevent uncontrolled movement of the hydraulically operated actuator.
  • an overload of the crane jib may occur under the following conditions.
  • a crane provided with a short jib it is possible to lift heavier loads than with a longer crane jib or with an extended jib.
  • a loading crane thus can lift a maximum load when the jib is retracted to its shortest outreach. If while lifting the length of the jib is increased while the load is suspended on the jib, for instance, by extending the hydraulic operated telescopic boom or raising the lufling end-jib there then occurs the possibility of overloading the control devices of the crane.
  • the increase of the outreach can be achieved in different ways, for instance by the extension of the telescopic boom after lifting the load or by raising the lufiing end-jib to which the load is suspended.
  • the present invention has for its object to overcome the above drawbacks by providing a device for limiting the power which may be produced by the working components of the hydraulic system.'
  • FIGURES 1-3 illustrate sectional schematic view of the 3,476,017 Patented Nov. 4, 1969 preferred embodiment of the invention shown in three dilferent working positions,
  • FIGURE 4 illustrates a sectional view of a prior art pilot-controlled and loading valve.
  • the illustrated embodiment of the device comprises the following main parts: an adjustable sensing means D, a pilot-controlled unloadingor relief valve E and a control valve means F.
  • the device may for instance operate in a loading crane provided with a lufiing end-jib which can be raised and lowered 'by means of a hydraulic cylinder A, a hydraulic operated winch B and a hydraulic pump C.
  • the sensing means D is arranged to sense the variable output of the working fluid-the hydraulic fluid in the present case-in the working components, that is to say in the hydraulic operated lifting cylinder A and the winch B.
  • the sensing means described comprises three sensing plungers 1, 2 and 3, which are spring-biased by means of helical springs 4, 5- and 6.
  • the spring-bias is adjustable by means of adjusting screws 7, 8 and 9, so that the sensing plungers 1, 2 and 3 can be biased to a suitable value in order to limit the power of the associated working component.
  • the prior art pilot-controlled valve E is connected to the hydraulic pump C and via a line 10 to the control valve F which at the inlet is provided with a check valve H.
  • the pilot valve of the valve E is connected to the pressure sensing means D via a line 13.
  • a return line 17 leads to the hydraulic fluid tank.
  • control valve F is provided with a check valve H, which prevents hydraulic fluid from flowing back to the connection line 10.
  • the winch B and the lifting piston A of the crane end-jib can be placed in the following three operating positions: lifting, stop and lowering by the appropriate positioning of operating levers 26 and 27, respectively.
  • hydraulic fluid is conveyed through the unloading valve E via a line 10 to the control valve F. If both operating levers 26 and 27 are in neutral position, the hydraulic fluid is conveyed right through the control valve F and back to the fluid tank G, that is to say, the hydraulic fluid circulates practically without pressure from the pump C through the valve E and the valve F to the fluid tank G.
  • the load can be lowered by means of the winch or the telescopic boom can be hydraulically retracted without the operation being influenced by the unloading valve E.
  • the latter valve can therefore be pre-adjusted to a suitable maximum pressure by means of a knob 18. If the adjusted pressure is reached or exceeded, for instance in the valve chamber of the pilot-controlled unloading valve, the valve plug 16 is raised against the action of a spring 24 (FIG- URE 4) and the return port 25 is partially opened until the pressure has again dropped to the preset value.
  • the hydraulic pressure which may rise to a maximum value set by means of the knob 18, will travel via line 10 to the control valve F and be admitted to the hydraulic motor B or the extension cylinder which in the present case can also be considered as represented by B.
  • the component B thus can be operated so as to lower the load or reduce the jib outreach. As long as this movement progresses, the plunger 1 will remain displaced to the left and the unloading valve will remain out of operation, this situation is illustrated in FIGURE 3.
  • the extension can only be carried out until the outreach has increased so that the pressure on the piston A, and consequently in the lines 11 and 12 as well as on the plunger 3 has reached such a value that the plunger 3 is displaced to the left in the FIGURE l-3, the pilot line 13 becomes pressureless and the valve plug 16 opens the return port 25 so that the line 10 is unloaded.
  • the sensing element associated with piston A operates and blocks any further supply of hydraulic pressure to the winch.
  • the load to be lifted is heavier than the permissible load to which the crane jib-may be subjected for the actual outreach, the load cannot be lifted and the operator thus realizes that he has to reduce the outreach.
  • the load can be lifted as soon as the outreach has been sufficiently decreased.
  • the device according to the invention thus provides the possibility of allowing the winch to be operated at a loading capacity corresponding to the actual crane jib outreach.
  • a singleacting cylinder for instance the end-jib lifting cylinder
  • a double-acting cylinder for instance, for extending and retracting the telescopic section of the crane jib can be connected in the same way as the winch B, that is to say, with a sensing element connected in parallel with a sensing element for the lifting cylinder A, the second sensing element for the retraction power being connected in the same way as the plunger 1.
  • All unloading functions for example, the lowering of the load, the decrease of the outreach and possibly the lowering of the lufling end-jib can thus be connected in the same way as the plunger 1 while the load-developing functions are connected in the same way as the plungers 2 and 3.
  • control device F which allows the operation of only one lever at a time.
  • each additional hydraulic cylinder added to the loading crane can be arranged in a similar way, for instance, a hydraulic operated extension and retraction of a telescopic boom, raising or lowering of a luffing end-jib, etc. Care should be taken to control and possibly limit the extension of the telescopic boom or the raise of the lufling end-jib; while the retraction or the lowering, usually does not cause an overload and therefore will not require any regulation.
  • the sensing means D can. also be arranged in another manner from that shown in the illustrated embodiment within the scope of the invention.
  • the plungers 1, 2 and 3 instead of directly opening the channel leading to the return line 15 may consist of plungers actuating check valves admitting the fluid pressure to the line 13 whereby the fluid pressure would actuate a pressurecontrolled check valve which would open and admit the fluid discharged from the pump C to the fluid tank G via a return line 17 and in this way limit the supply of hydraulic fluid to the working component, which supply would otherwise cause a load increase on an already overloaded component.
  • a substantial feature of the invention is that when a certain component is subjected to a maximum load there is no possibility to operate any additional components than those which are to be operated for either lowering the load or reducing the outreach or lowering the lufling end-jib.
  • a hydraulic system for controlling hydraulically actuated working components comprising a reservoir tank, a source of hydraulic pressure connected thereto, a pilot control valve means with an inlet port connected to the source of hydraulic pressure, a fluid control valve means connected to the working components, a first fluid connection means between the pilot control valve means and the fluid control valve, means for simultaneously and individually sensing the pressure in each of the hydraulically actuated working components, a pilot fluid connected means between the pilot control valve and the pressure sensing means, and a second fluid connection means between the pilot control valve means and the reservoir tank whereby the pressure sensing means can at a predetermined pressure in the working components cause the pilot control valve to unload and thereby maintain a constant pressure below overload in at least one of the working components.
  • a hydraulic system as in claim 1 wherein the means for sensing the pressure in the hydraulic actuated working components is capable of loading and unloading the pilot control valve by the closing and opening of the fluid path in the pilot fluid connection means.
  • a hydraulic system as in claim 2, wherein the means for sensing the pressure in the hydraulic actuated working components includes at least one plunger with one side in fluid communication with the working hydraulic fluid and the other side in communication with the pilot fluid from the pilot control valve.
  • a hydraulic system as in claim 3 wherein the means for sensing the pressure in the hydraulic actuated working components includes a second plunger with one end in fluid communication with the hydraulic fluid being supplied a second working component, the second plunger being capable of closing the fluid path in the pilot fluid connection means for the purpose of loading the pilot control valve to provide a source of hydraulic pressure for the second working component while maintaining pressure in another working component.
  • pilot control valve means includes a pressure limiting means.
  • pilot control valve means includes a movable piston containing a restrictive orifice for establishing an operative fluid connection with the pressure sensing means.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Jib Cranes (AREA)
  • Control And Safety Of Cranes (AREA)
  • Preparation Of Compounds By Using Micro-Organisms (AREA)
US627916A 1966-04-29 1967-04-03 Power-limiting device for a machine provided with two or more working components Expired - Lifetime US3476017A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
SE5886/66A SE310846B (en, 2012) 1966-04-29 1966-04-29

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US3476017A true US3476017A (en) 1969-11-04

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US627916A Expired - Lifetime US3476017A (en) 1966-04-29 1967-04-03 Power-limiting device for a machine provided with two or more working components

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US (1) US3476017A (en, 2012)
DE (1) DE1506487B1 (en, 2012)
FI (1) FI47430C (en, 2012)
GB (1) GB1186447A (en, 2012)
NL (1) NL6705293A (en, 2012)
NO (1) NO120171B (en, 2012)
SE (1) SE310846B (en, 2012)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4157736A (en) * 1978-01-11 1979-06-12 Carbert Ralph E Overload protection apparatus for hydraulic multi-function equipment
US7080891B1 (en) * 1999-08-02 2006-07-25 Knorr-Bremse Systeme Fuer Nutzfahrzeuge Safety device for an automotive pneumatic system
US20120073678A1 (en) * 2010-09-24 2012-03-29 Mike Winn Safety valve system for overpressure protection of hydraulic circuits

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3814265A (en) * 1973-08-20 1974-06-04 Harnischfeger Corp Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded
US5332110A (en) * 1993-02-22 1994-07-26 Vanguard Hydraulic Pipelayer Tractor mounted hydraulic pipelayer with side boom
US6609622B2 (en) 2001-07-23 2003-08-26 Raymond Forsyth Bulldozer/pipelayer combination

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US2318851A (en) * 1938-01-26 1943-05-11 Vickers Inc Power transmission for machine tools
US2465758A (en) * 1944-09-29 1949-03-29 American Steel Foundries Control circuit for fluid actuated motors
US2495669A (en) * 1947-09-27 1950-01-24 American Steel Foundries Fluid apparatus
US2527943A (en) * 1944-04-10 1950-10-31 Jeffrey Mfg Co Hydraulic valve and system
US2568528A (en) * 1944-08-05 1951-09-18 Colonial Broach Co Valve and hydraulic circuit therefor
US3073331A (en) * 1959-03-17 1963-01-15 Faisandier Jacques Unloading valve for a hydraulic pressure circuit

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DD38568A (en, 2012) *
DE800137C (de) * 1948-10-02 1950-09-22 Augsburg Nuernberg A G Zweigni Endschaltung fuer Dieselkrane mit pneumatischer Steuerung
DE959129C (de) * 1955-03-12 1957-02-28 Demag Zug Gmbh Einrichtung zur selbsttaetigen Begrenzung des Lastmomentes bei Wippauslegern
DE1076927B (de) * 1957-03-20 1960-03-03 Demag Zug Gmbh Einrichtung zur selbsttaetigen Begrenzung des Lastmomentes bei Wippauslegern

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2318851A (en) * 1938-01-26 1943-05-11 Vickers Inc Power transmission for machine tools
US2527943A (en) * 1944-04-10 1950-10-31 Jeffrey Mfg Co Hydraulic valve and system
US2568528A (en) * 1944-08-05 1951-09-18 Colonial Broach Co Valve and hydraulic circuit therefor
US2465758A (en) * 1944-09-29 1949-03-29 American Steel Foundries Control circuit for fluid actuated motors
US2495669A (en) * 1947-09-27 1950-01-24 American Steel Foundries Fluid apparatus
US3073331A (en) * 1959-03-17 1963-01-15 Faisandier Jacques Unloading valve for a hydraulic pressure circuit

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4157736A (en) * 1978-01-11 1979-06-12 Carbert Ralph E Overload protection apparatus for hydraulic multi-function equipment
US7080891B1 (en) * 1999-08-02 2006-07-25 Knorr-Bremse Systeme Fuer Nutzfahrzeuge Safety device for an automotive pneumatic system
US20120073678A1 (en) * 2010-09-24 2012-03-29 Mike Winn Safety valve system for overpressure protection of hydraulic circuits
US8671972B2 (en) * 2010-09-24 2014-03-18 Mike Winn Safety valve system for overpressure protection of hydraulic circuits

Also Published As

Publication number Publication date
GB1186447A (en) 1970-04-02
FI47430C (fi) 1973-11-12
NO120171B (en, 2012) 1970-09-07
DE1506487B1 (de) 1970-11-26
FI47430B (en, 2012) 1973-07-31
NL6705293A (en, 2012) 1967-10-30
SE310846B (en, 2012) 1969-05-12

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