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GB1412918A - Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded - Google Patents

Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded

Info

Publication number
GB1412918A
GB1412918A GB2202874A GB2202874A GB1412918A GB 1412918 A GB1412918 A GB 1412918A GB 2202874 A GB2202874 A GB 2202874A GB 2202874 A GB2202874 A GB 2202874A GB 1412918 A GB1412918 A GB 1412918A
Authority
GB
United Kingdom
Prior art keywords
boom
pressure
fluid
valve
poppet
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
Application number
GB2202874A
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.)
Harnischfeger Corp
Original Assignee
Harnischfeger 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 Harnischfeger Corp filed Critical Harnischfeger Corp
Publication of GB1412918A publication Critical patent/GB1412918A/en
Expired legal-status Critical Current

Links

Classifications

    • 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
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C13/00—Other constructional features or details
    • B66C13/18—Control systems or devices
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2203—Arrangements for controlling the attitude of actuators, e.g. speed, floating function
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C2700/00—Cranes
    • B66C2700/06—Cranes in which the lifting movement is done with a hydraulically controlled plunger
    • 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
    • F15B2211/205—Systems with pumps
    • F15B2211/20576—Systems with pumps with multiple pumps
    • 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
    • F15B2211/3053—In combination with a pressure compensating valve
    • F15B2211/30535—In combination with a pressure compensating valve the pressure compensating valve is arranged between pressure source and 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
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • 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
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3122—Special positions other than the pump port being connected to working ports or the working ports being connected 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
    • F15B2211/405—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
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40546—Flow control characterised by the type of flow control means or valve with flow combiners
    • 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
    • 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
    • F15B2211/5153—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve
    • F15B2211/5155—Pressure control characterised by the connections of the pressure control means in the circuit being connected to an output member and a directional control valve being connected to multiple 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
    • F15B2211/60—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
    • F15B2211/6054—Load sensing circuits having valve means between output member and the load sensing circuit using shuttle 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/65—Methods of control of the load sensing 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
    • F15B2211/60—Circuit components or control therefor
    • F15B2211/67—Methods for controlling pilot 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
    • F15B2211/70—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
    • F15B2211/7114—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators
    • F15B2211/7128—Multiple output members, e.g. multiple hydraulic motors or cylinders with direct connection between the chambers of different actuators the chambers being connected in parallel
    • 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
    • F15B2211/7142—Multiple output members, e.g. multiple hydraulic motors or cylinders the output members being arranged in multiple groups
    • 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
    • F15B2211/715—Output members, e.g. hydraulic motors or cylinders or control therefor having braking means

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Automation & Control Theory (AREA)
  • Jib Cranes (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Control And Safety Of Cranes (AREA)

Abstract

1412918 Valves HARNISCHFEGER CORP 17 May 1974 [20 Aug 1973] 22028/74 Heading F2V [Also in Division F1] In a mobile crane, Fig. 1, each component is operated by a ram or a hydraulic motor controlled by an operator-actuated control valve. The control valves 71-74, Fig. 2, and 81-83 are arranged in two bankes 64, 63 which are supplied from engine-driven pumps 37, 27. Boom hoist cylinders 21, for luffing the boom, are provided with a pilot valve 118 which operates a holding valve 116, which, when closed, prevents movement of the boom. Electrohydraulic means are provided to dump hydraulic fluid from each control bank 63, 64 and from the pilot valve 118 if a crane component, such as the boom, approaches a predetermined safe limit. This prevents the control valves from supplying the rams or motors and causes valve 116 to lock the boom. The electrohydraulic means comprise a conventional weigh-load device 104 which actuates, by means of a relay 160, a plurality of solenoid valves 100, 101 and 102 which simultaneously dump fluid from the control valve banks 63, 64 and the pilot valve 118. Manual override means including switches 155, 156 enable the boom to be brought back within safe limits. Fig. 6 shows a control valve 71 which has a main control spool SP and a compensating spool CP. The latter is spring loaded and moves in response to the main pressure P and a pressure P1 produced by pressure drop across one of the loads of the spool SP, to ensure that the controlled function is independant of load and pressure variations Fig. 7 shows the inlet section 62 of contro bank 64. This includes an unloading poppet 110 which dumps fluid when there is zero demand from the spools, a by-pass poppet 180 which proportions fluid between the reservoir and the spools, and a main relief poppet 182. Signal pressure exists in chamber 112 and when the overload device 104 senses an overload overload condition fluid is damped from port 114 reducing the pressure in chamber 112 and opening unloading poppet 110.
GB2202874A 1973-08-20 1974-05-17 Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded Expired GB1412918A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US00389882A US3814265A (en) 1973-08-20 1973-08-20 Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded

Publications (1)

Publication Number Publication Date
GB1412918A true GB1412918A (en) 1975-11-05

Family

ID=23540139

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2202874A Expired GB1412918A (en) 1973-08-20 1974-05-17 Hydraulic crane control system having means for deactivating control valves when operating limit is exceeded

Country Status (5)

Country Link
US (1) US3814265A (en)
JP (1) JPS5043657A (en)
DE (1) DE2433437C2 (en)
FR (1) FR2302956A1 (en)
GB (1) GB1412918A (en)

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4336720A (en) * 1980-08-22 1982-06-29 Lull Engineering Company, Inc. Load sensing system
IT8040102A0 (en) * 1980-11-28 1980-11-28 Ferrari Snc Di Gianni E Romano MOMENT LIMITING DEVICE FOR ARTICULATED ARM CRANES PARTICULARLY INTENDED FOR INSTALLATION ON TRUCKS.
AT368107B (en) * 1980-12-23 1982-09-10 Palfinger Fa LOADING CRANE
US4523686A (en) * 1982-07-28 1985-06-18 Fmc Corporation Anti-two block system
US4662527A (en) * 1983-04-22 1987-05-05 Fmc Corporation Hydraulic circuit for self-undecking crane
US4632261A (en) * 1983-04-22 1986-12-30 Fmc Corporation Hydraulic circuit for self-undecking crane
US4598829A (en) * 1983-06-29 1986-07-08 Fmc Corporation Hydraulic circuit for crane
US5116188A (en) * 1987-09-16 1992-05-26 Kabushiki Kaisha Kobe Seiko Sho Vibration suppressing device for wheeled construction equipment
JPH0297437U (en) * 1989-01-23 1990-08-02
JPH0662268B2 (en) * 1989-04-21 1994-08-17 株式会社神戸製鋼所 Displacement restraint device for mobile crane
JPH0639317B2 (en) * 1989-09-09 1994-05-25 株式会社神戸製鋼所 Displacement suppression mechanism for mobile cranes
JPH0815998B2 (en) * 1989-10-14 1996-02-21 株式会社神戸製鋼所 Vibration suppressor for wheeled crane
JP3153118B2 (en) * 1996-02-01 2001-04-03 新キャタピラー三菱株式会社 Hydraulic circuit of hydraulic work machine
ITPC20060029A1 (en) * 2006-07-12 2008-01-13 Laurini Officine Meccaniche Srl PERFORMED HANGING MACHINE
CN101839260B (en) * 2010-03-21 2011-11-23 常德中联重科液压有限公司 Step-down multipath reversing valve with two-position two-way hydraulic control valve
DE102011105819A1 (en) * 2011-05-27 2012-11-29 Liebherr-Werk Nenzing Gmbh Crane with overload protection
US20150307337A1 (en) * 2012-12-07 2015-10-29 Linepro Equipment Ltd. Vehicle mounted crane boom assembly with a dielectric boom arm
CN104995412B (en) * 2013-03-22 2017-03-29 株式会社日立建机Tierra The fluid pressure drive device of engineering machinery
CN105987037B (en) * 2015-02-15 2018-07-17 徐工集团工程机械股份有限公司 Control valve, control connection, proportional multi-way valve and the crane of proportional multi-way valve
US10119556B2 (en) * 2015-12-07 2018-11-06 Caterpillar Inc. System having combinable transmission and implement circuits
CN113548593A (en) * 2020-04-23 2021-10-26 成都耐特恩科技有限公司 Group tower operation safety monitoring system and method
SI26379A (en) * 2022-07-13 2024-01-31 Tajfun Liv, Proizvodnja In Razvoj D.O.O. Hydraulic circuit of a mobile hydraulic lift

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SE310846B (en) * 1966-04-29 1969-05-12 Tico Ab
US3371799A (en) * 1967-03-01 1968-03-05 Baldwin Lima Hamilton Corp Telescopic boom angle control system
US3690387A (en) * 1971-02-16 1972-09-12 Bouligny Inc R H Boom rotation brake release means for derricks
DE2164628C3 (en) * 1971-12-24 1978-03-16 Siegfried Dipl.-Ing. Dr.-Ing. 4930 Detmold Gross Overload cut-off device for hydraulic lifting and lifting devices coupled in series. Adjustment mechanisms

Also Published As

Publication number Publication date
JPS5043657A (en) 1975-04-19
DE2433437A1 (en) 1975-03-06
US3814265A (en) 1974-06-04
FR2302956B1 (en) 1978-03-31
FR2302956A1 (en) 1976-10-01
DE2433437C2 (en) 1984-09-06

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Legal Events

Date Code Title Description
PS Patent sealed [section 19, patents act 1949]
PCNP Patent ceased through non-payment of renewal fee