EP1239167B1 - Dispositif de levage hydraulique - Google Patents

Dispositif de levage hydraulique Download PDF

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Publication number
EP1239167B1
EP1239167B1 EP02004809A EP02004809A EP1239167B1 EP 1239167 B1 EP1239167 B1 EP 1239167B1 EP 02004809 A EP02004809 A EP 02004809A EP 02004809 A EP02004809 A EP 02004809A EP 1239167 B1 EP1239167 B1 EP 1239167B1
Authority
EP
European Patent Office
Prior art keywords
valve
line
hydraulic
branch line
lifting device
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
EP02004809A
Other languages
German (de)
English (en)
Other versions
EP1239167A1 (fr
Inventor
Octavian Mare
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.)
Dambach Lagersysteme & Co KG GmbH
Original Assignee
Dambach Lagersysteme & Co KG GmbH
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 Dambach Lagersysteme & Co KG GmbH filed Critical Dambach Lagersysteme & Co KG GmbH
Publication of EP1239167A1 publication Critical patent/EP1239167A1/fr
Application granted granted Critical
Publication of EP1239167B1 publication Critical patent/EP1239167B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/20—Means for actuating or controlling masts, platforms, or forks
    • B66F9/22—Hydraulic devices or systems
    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/14—Energy-recuperation means

Definitions

  • the invention relates to a hydraulic lifting device especially for battery-powered industrial trucks, with a driven by an electric motor pump by means of in the lifting operation, at least one hydraulic lifting cylinder Hydraulic oil from a reservoir via a supply line can be supplied, wherein in a suction-side section the supply line a Nachsaugventil is arranged and wherein the hydraulic oil in the load lowering operation of the lifting cylinder via a return line while flowing through a the driving as a generator electric motor driving hypromotor can be returned to the reservoir, and with a control device for changing the lifting or lowering speed the lifting cylinder, wherein the supply line a Having branch line, on the hydraulic lifting oil in the lifting operation is branched off from the supply and the in the suction-side portion of the supply line downstream of the Suction valve opens.
  • the hydraulic motor drives a generator or the generator in this state working electric motor, from which by means of a suitable, known per se electrical circuit for energy recovery the associated battery is charged.
  • the Speed of the electric motor for controlling the lifting or lowering speed of the hydraulic lifting cylinder used only when the lifting cylinder is adjusted sufficiently quickly or the stroke speed encompassed by a sensor device a predetermined first limit value or the lowering speed exceed a predetermined second threshold. If the lift cylinder at a relatively low speed is adjusted below the specified limits, such as for example, when starting from the rest position due inertia and also at a selected crawl speed the case is, the speed of the lift cylinder not via the speed of the electric motor and thus of the pump, but via the volume or mass flow of the in the feed or return line of flowing hydraulic oil changed. To this Purpose, the supply of a branch line, via in the lifting operation hydraulic oil from the supply line is branchable.
  • the branch line opens into the suction side Ab. cut the supply line downstream of the Nachsaugventils, so that fed the diverted amount of hydraulic oil to the pump again becomes. In this way, it adjusts itself in all modes favorable efficiency.
  • the Suction conditions of the pump with frequent activation of auxiliary functions especially at very low and in the load lifting operation at relatively high speeds to increased cavitation wear lead, what the life of the pump is disadvantageous.
  • the invention is based on the object, a hydraulic To provide lifting device of the type mentioned, in which an excessive Wear of the pump is reliably avoided.
  • the suction valve according to the invention thus decreases under the spring action the position of free flow as basic position one. As long as the pump is operating in pump mode, that of the pump sucked from the reservoir unobstructed amount of oil and free through the suction valve to the suction side of the Pump the pump.
  • the hydraulic oil becomes from the hydraulic one Lifting cylinder via the branch line, which is also part of the Return line is the suction-side section of the supply line fed back downstream of the Nachsaugventils.
  • the Suction valve from its open position or position Free flow switched to its check valve position, in the pump while hydraulic oil from the reservoir can suck.
  • the hydraulic oil flowing back through the branch line must thus flow through the pump. If the pump is due to their speed a larger amount of oil than the amount of backflowing Oil needed, the difference in quantity over the in the check valve position located Nachsaugventil be sucked into the reservoir.
  • the suction valve may be an electrically actuated Act act valve, in a preferred embodiment is the Nachsaugventil however, a hydraulically switchable valve, the at a sufficient fluid pressure in the branch line directly is switched by means of this fluid pressure. It is in the Branch line arranged a check valve whose opening pressure essentially the switching pressure of the Nachsaugventils in the check valve position corresponds.
  • the opening pressure of the Check valve thus also applies as the minimum control pressure for the Nachsaugventil and is determined so that he Pretension force of the suction valve in the position of free flow can overcome and the intake valve reliable in brings his check valve position and holds in this.
  • the circuit of the Nachsaugventils takes place in that stromau the check valve from the branch line one to the suction valve leading switching line branches, in which the stromau the check valve in the branch line prevailing fluid pressure acts.
  • the branch line through the arranged in this flow control valve must the suction valve due to the spring preload return to its free flow position. That's it makes sense, which may be in the branch line and the Can reduce the shift line located pressure.
  • This is according to the invention achieved by the downstream of the check valve between the branch line of the switching line a discharge line runs, in which a nozzle is arranged over the the residual pressure is reduced.
  • the branch line is also part of Return line, so that the existing in the branch line Current regulator valve at the same time also the flow control valve of the Return line is.
  • the acceleration, Delay and low speed operations because of the relatively low system stiffness no longer with the desired Precision run, which adversely affects has the positioning properties of the lifting device. If that Flow control valve of the branch line and thus the return line as a controller with hydraulic load compensation, i. so-called Pressure compensator, is formed, these adverse occur Appearances intensified, as the hydraulic pressure compensator her Own time ratio brings.
  • FIG. 1 shows a schematic circuit diagram of a device according to the invention hydraulic lifting device shows.
  • a hydraulic lifting device shown in the figure 10 includes a reservoir 11 for hydraulic oil, the via a supply line consisting of several sections L1 and subsequent connection lines L4.1 and L4.2 with. two hydraulic lifting cylinders 13 is connected. The im the following information used "upstream” and “downstream” to an oil flow from the reservoir 11 to the lift cylinders 13, i. in the feeding direction for the lifting operation.
  • the supply line L1 in turn consists of several line sections built up.
  • a first section L1.1 leads from Reservoir 11 to a hydraulic pump P, by means of a Electric motor M is driven by a power connection 21 Energy from a battery, not shown refers.
  • a leakage line L3 returns in the storage tank 11.
  • section L1.1 of Feed line L which shows the suction-side section, a Nachsaugventil 12 is arranged, the hydraulic is adjustable and under spring load in an open Position free flow is biased in the the hydraulic oil in the section L1.1 in both directions can flow.
  • the Nachsaugventil 12 can also counter the spring load in a check valve position be adjusted, the an oil flow in the feed direction, i.e. from the reservoir 11 to the pump P permits and prevents backflow.
  • a second section closes L1.2 of the supply line L1, to a check valve 15th
  • the check valve 15 is by means a spring biased into a blocking position, which it Automatically assumes in case of power failure.
  • a first Check valve 14 is arranged, which is also only an oil flow in the feed direction, i. to the lifting cylinders 13 permits and prevents backflow.
  • a third section L1.3 of the supply line closes L1 on, which at its downstream end in the two Connecting lines L4.1 and L4.2 branches, respectively lead to one of the hydraulic lifting cylinders.
  • the flow control valve 16 is as Throttle valve designed without hydraulic load compensation.
  • a second one Check valve 12.1 arranged, which has a flow in Direction of the suction-side first portion L1.1 of the supply line L1 allows and over the bias of a Spring defined a certain opening pressure.
  • a switching line L8 from which to the suction valve 12 leads and over the suction valve 12, a switching pressure can be fed.
  • Downstream of the second check valve 12.1 is between the branch line L2 and the switching line L8 a discharge line L9 is formed, in which a nozzle 12.2 is arranged to equalize the pressure.
  • the two lifting cylinders 13 is one only schematically associated sensor device 20 associated with the current Position of the lifting cylinder 13 and the load detected and a corresponding control signal to a processing unit in which the lifting or lowering speed of Lifting cylinder is calculated.
  • Lifting device 10 The following are different modes of operation of Lifting device 10 explains:
  • He is in the branch line L2 adjusting hydraulic pressure is greater than the opening pressure of the second check valve 12.1, so that the hydraulic oil in the suction-side section L1.1 of the supply line L1 is returned.
  • the in the branch line L2 prevailing oil pressure is also on the L8 switching line the suction valve 12 is effective and switches this in the Check valve position, which ensures that via the branch line L2 into the suction-side section L1.1 of the supply line L1 returned hydraulic oil not can flow back into the reservoir 11, but in turn the pump P must flow through.
  • the flow cross section of the flow control valve 16 increases and thus the volume flow of hydraulic oil to the lifting cylinders be reduced.
  • the change in the lifting speed of the lifting cylinder 13, which takes place either via a control of the flow control valve 16 for the purpose of changing the fürflußqueriteses or by a control of the electric motor for the purpose of changing the speed is carried out in dependence on the current lifting speed, which is detected by the sensor devices 20. If the current lifting speed is below a predetermined limit, the change in the lifting speed is done solely by driving the flow control valve. If the current lifting speed is above the limit value, the change in the lifting speed is effected solely by driving the electric motor M, wherein it is ensured in this state that the rotational speed of the electric motor M is above a minimum speed of, for example 500min -1 .
  • the hydraulic oil flowing back through the branch line L2 enters the first section L1.1 of the supply line L1 between the suction valve 12 and the pump P, wherein a backflow into the reservoir 11 through the located in the check valve position Nachsaugventil 12 is prevented.
  • the hydraulic oil then flows through the pump P, which operates as a hydraulic motor in this state, enters the second section L1.2 of the supply line L1 and steps out of it into the bypass line L6 and from this via the bypass line L7 and the opened further Blocking valve 18 in the leading to the reservoir 11 drain line L5 on.
  • the pump P acts as a hydraulic motor and is of the hydraulic oil in the same direction as in the load lifting operation flows through.
  • the pump P drives the electric motor, while doing while idling, so that the hydraulic oil depressurized returned to the reservoir 11 can be.
  • a change in the lowering speed can within certain limits by changing the flow area of the flow control valve 16 can be achieved.
  • Turn the pump P and the electric motor M at a speed according to the minimum speed and the associated Lowering speed of the lifting cylinder 13 corresponds to the Limit.

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  • Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Civil Engineering (AREA)
  • Geology (AREA)
  • Combustion & Propulsion (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Claims (7)

  1. Dispositif de levage hydraulique pour chariots de manutention fonctionnant sur batteries, comprenant une pompe (P) entraínée par un moteur électrique (M) au moyen de laquelle on peut amener durant l'opération de levage, à au moins un vérin hydraulique (13), de l'huile hydraulique à partir d'un réservoir (11) à travers un conduit d'alimentation (L1), dans lequel un clapet d'aspiration (12) est disposé dans une partie (L1.1) du conduit d'alimentation (L1) située côté admission, et dans lequel l'huile hydraulique peut, durant l'opération de descente, être réacheminée du vérin hydraulique (13) à travers un conduit de retour (L4.1, L4.2, L1.3, L2, L1.1, L1.2, L6, L7, L5) dans le réservoir (11) en passant dans un moteur hydraulique (P) actionnant le moteur électrique (M) fonctionnant comme un générateur, et comprenant un dispositif de commande (16) pour modifier la vitesse de levage ou de descente du vérin hydraulique (13), dans lequel le conduit d'alimentation (L1) présente une dérivation (L2), à travers laquelle on peut, durant l'opération de levage, dériver de l'huile hydraulique à partir du conduit d'alimentation et qui débouche dans la partie (L1.1) du conduit d'alimentation (L1) située côté admission en aval du clapet d'aspiration (12), caractérisé en ce que le clapet d'aspiration (12) peut être basculé, en fonction de la pression régnant dans la dérivation (L2), entre une position ouverte de passage libre et une position de clapet antiretour, dispositif dans lequel un clapet antiretour (12.1) est disposé dans la dérivation (L2), dont la pression d'ouverture correspond sensiblement à la pression de commutation du clapet d'aspiration (12) dans la position de clapet antiretour, et dans lequel en amont du clapet antiretour (12.1) un conduit de commutation menant au clapet d'aspiration (12) se sépare de la dérivation (L2) et dans lequel un conduit de décharge (L9), dans lequel est disposée une buse (12.2), s'étend en aval du clapet antiretour (12.1) entre la dérivation (L2) et le conduit de commutation (L8).
  2. Dispositif de levage hydraulique selon la revendication 1, caractérisé en ce que le clapet d'aspiration (12) est précontraint dans la position de passage libre.
  3. Dispositif de levage hydraulique selon la revendication 1 ou 2, caractérisé en ce qu'une soupape de régulation de débit (12) est disposée dans la dérivation, qui permet de modifier le débit volume d'huile hydraulique amené au vérin hydraulique (13), et en ce qu'une soupape de régulation de débit (16) est disposée dans le conduit de retour, qui permet de modifier le débit volume de l'huile hydraulique réacheminée à partir du vérin hydraulique (13) dans le réservoir (11).
  4. Dispositif de levage hydraulique selon l'une quelconque des revendications 1 à 3, caractérisé en ce que la dérivation (L2) constitue en même temps une partie du conduit de retour.
  5. Dispositif de levage hydraulique selon l'une quelconque des revendications 1 à 4, caractérisé en ce que le clapet d'aspiration (12) est conformé en clapet électrique d'inversion.
  6. Dispositif de levage hydraulique selon l'une quelconque des revendications 1 à 5, caractérisé en ce que la soupape de régulation de débit (16) est une vanne papillon sans compensation hydraulique de charge.
  7. Dispositif de levage hydraulique selon l'une quelconque des revendications 1 à 6, caractérisé en ce qu'une boucle d'asservissement induisant une compensation de charge électro-hydraulique se trouve entre un dispositif de détection (20) permettant de détecter le déplacement du vérin hydraulique (13) et la soupape de régulation de débit (16).
EP02004809A 2001-03-07 2002-03-02 Dispositif de levage hydraulique Expired - Lifetime EP1239167B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10110764 2001-03-07
DE10110764A DE10110764A1 (de) 2001-03-07 2001-03-07 Hydraulische Hubvorrichtung

Publications (2)

Publication Number Publication Date
EP1239167A1 EP1239167A1 (fr) 2002-09-11
EP1239167B1 true EP1239167B1 (fr) 2005-01-12

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EP02004809A Expired - Lifetime EP1239167B1 (fr) 2001-03-07 2002-03-02 Dispositif de levage hydraulique

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EP (1) EP1239167B1 (fr)
DE (2) DE10110764A1 (fr)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011040552A1 (fr) 2009-10-01 2011-04-07 本田技研工業株式会社 Soupape de commande de débit de liquide
CN103195773B (zh) * 2013-03-26 2015-12-23 湖州机床厂有限公司 一种柔性卸荷的液压系统

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH02209400A (ja) * 1989-02-10 1990-08-20 Toyota Autom Loom Works Ltd バッテリ式産業車両における油圧装置
JPH0323199A (ja) * 1989-06-19 1991-01-31 Toyota Autom Loom Works Ltd バッテリ式産業車両における油圧装置
DE19921629B4 (de) * 1999-05-10 2005-05-25 Dambach Lagersysteme Gmbh Hydraulische Hubvorrichtung

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DE50201975D1 (de) 2005-02-17
DE10110764A1 (de) 2002-09-19
EP1239167A1 (fr) 2002-09-11

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