EP1004542A1 - Hydraulic system especially for an industrial truck - Google Patents

Hydraulic system especially for an industrial truck Download PDF

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Publication number
EP1004542A1
EP1004542A1 EP99123341A EP99123341A EP1004542A1 EP 1004542 A1 EP1004542 A1 EP 1004542A1 EP 99123341 A EP99123341 A EP 99123341A EP 99123341 A EP99123341 A EP 99123341A EP 1004542 A1 EP1004542 A1 EP 1004542A1
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EP
European Patent Office
Prior art keywords
tank
hydraulic
working machine
machine according
hydraulic pump
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Granted
Application number
EP99123341A
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German (de)
French (fr)
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EP1004542B1 (en
Inventor
Rainer Dr.-Ing. Bavendiek
Claus-Peter Dipl.-Ing. Jahns
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STILL GmbH
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STILL GmbH
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    • 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
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B17/00—Pumps characterised by combination with, or adaptation to, specific driving engines or motors
    • F04B17/03—Pumps characterised by combination with, or adaptation to, specific driving engines or motors driven by electric motors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B23/00—Pumping installations or systems
    • F04B23/02—Pumping installations or systems having reservoirs
    • F04B23/021—Pumping installations or systems having reservoirs the pump being immersed in the reservoir
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B23/00—Pumping installations or systems
    • F04B23/02—Pumping installations or systems having reservoirs
    • F04B23/021—Pumping installations or systems having reservoirs the pump being immersed in the reservoir
    • F04B23/023—Pumping installations or systems having reservoirs the pump being immersed in the reservoir only the pump-part being immersed, the driving-part being outside the reservoir
    • 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
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/26—Supply reservoir or sump assemblies

Definitions

  • the invention relates to a work machine, in particular industrial truck, with a hydraulic system that has at least one tank for hydraulic fluid and at least has a hydraulic pump.
  • Working machines are often equipped with a hydraulic system, via which, depending on the construction of the machine, drives different Functions of the working machine is carried out. This is the case with industrial trucks usually about lifting and tilting a load, about steering the Industrial truck and possibly additional functions for handling Loads.
  • the hydraulic system usually has a tank, from which a Pump hydraulic fluid is sucked in.
  • the pump is switched on Priority valve, which preferably has a hydraulic steering device Hydraulic fluid supplied.
  • hydraulic fluid becomes over arbitrary controllable directional valves available to other hydraulic consumers posed. These are usually hydraulic cylinders with which to Lifting, tilting or handling a load required forces are generated.
  • the steering device and the other hydraulic consumers are still connected to the tank via return lines, with in the return lines if necessary, a lowering brake to reduce the flow rate Hydraulic fluid, or a bias valve to maintain a predetermined Pressure levels can be arranged in the corresponding return line.
  • hydraulic components mentioned are in the state of the art technology usually separated from each other on a frame of Work machine attached and with each other via hose or pipes connected. It is also known to different hydraulic components Summarize assemblies and together on the framework of the Attach work machine. In any case, known hydraulic systems however, a number of parting lines and junctions with seals various types are sealed against the leakage of hydraulic fluid.
  • the present invention has for its object a generic To provide work machine at which the risk of leakage from Hydraulic fluid is reduced with simple means.
  • the hydraulic pump is arranged inside the tank. If there is a leak in the housing Hydraulic pump or its hydraulic connections flows the escaping Hydraulic oil directly into the tank. This will contaminate the Machine and the environment safely prevented. Sealing this up leaks are only in the case of gross damage to the sealing elements required if the escaping hydraulic fluid causes a loss of performance hydraulic system leads. Minor leaks can occur regularly maintenance work that is taking place must be remedied since it Work machine pose no danger to operational safety and the environment. On Another advantage of the arrangement of the pump in the tank is that in the event of leaks Places in a suction area of the pump, for example on an intake pipe or on a filter, entry of air into the hydraulic pump and thus one Damage due to cavitation is avoided.
  • an electric drive motor Hydraulic pump is arranged inside the tank. It is not a mechanical one Rotary feedthrough through a wall of the tank required. That in the tank hydraulic fluid is also used as a coolant for the electrical Drive motor.
  • the arrangement of the electric drive motor inside the tank lends itself particularly well when a maintenance-free three-phase motor is used.
  • a further improvement with regard to the leakage of hydraulic fluid results if a priority valve is located inside the tank.
  • the priority valve provides sure that a steering device of the working machine is always sufficient Hydraulic fluid is supplied. Leaks in the area of the priority valve, for example at the hydraulic connection points, lead with this arrangement not to pollute the environment with hydraulic fluid. Instead it will the leaking hydraulic fluid is caught in the tank.
  • Hydraulic pump and priority valve can be pre-assembled Unit to be installed in the tank.
  • At least one directional control valve is located inside the tank is arranged.
  • the supply of hydraulic fluid is blocked by means of the directional control valves different hydraulic consumers depending on one of one Operator generated signal controlled. Leakages of these are usually proportional controllable directional valves, which can also be designed as slide valves, are caught by the tank.
  • slide valves the devices in the State of the art required complex tank return due to the design resulting leakage oil can be dispensed with. It is even possible on the usual used seals against contamination of the slide valves, because due to the arrangement in the tank, they are not exposed to external influences.
  • the directional control valve is electrically controllable.
  • the directional control valves can thus be spatially be arranged independently of the respectively assigned control lever.
  • directional control valves are provided, one Form directional valve block.
  • the directional valve block can be pre-assembled in the tank become.
  • the priority valve is a component of the directional valve block with particular advantage. There is therefore no need for hydraulic lines to connect the priority valve connect with the directional valve block.
  • the steering valve can also be designed as part of the directional valve block his.
  • Additional advantages result if additional hydraulic components, for example one or more preload valves and / or a lowering brake valve, are arranged inside the tank.
  • Preload valve and lowering brake valve are in arranged the return lines of hydraulic consumers. This too Components can be arranged according to the invention within the tank.
  • the figure shows a tank 1 of a hydraulic system of a work machine.
  • the Tank 1 is sealed with a tank hood 2.
  • a number of components of the hydraulic system are arranged.
  • An electric drive motor 3 designed as a three-phase motor is located below the fill line 4 of the tank 1 and is thus from the surrounding Hydraulic fluid cooled.
  • a hydraulic pump is flanged to the drive motor 3 5, which is driven by the drive motor 3.
  • the hydraulic pump 5 sucks a suction filter 6, which is arranged in a suction pipe 7, hydraulic fluid from the Tank 1 on.
  • the hydraulic pump 5 is connected to the hydraulic pump 5 in the area of an outlet opening a directional valve block 8 flanged, which in this embodiment Priority valve 8a, a steering valve 8b and two directional control valves 8c, 8d. Of the The steering valve 8b and the directional control valves 8c, 8d run over a flange plate 10 hydraulic pressure lines 9 to the respective hydraulic consumers.
  • the tank hood 2 there is also a bushing for electrical lines arranged.
  • a control and supply line 11 for the electrical Drive motor 3 and signal lines 12 to the steering valve 8b and Directional control valves 8c, 8d are provided.
  • the signal lines are with the corresponding ones Control levers or a steering sensor connected to which electrical Control signals are generated.
  • FIG. 1 Also shown are two return lines 13 through which hydraulic fluid from flows back to the various hydraulic consumers in tank 1.
  • the Return lines 13 are via a flange plate 14 through the tank hood 2 in led the tank 1.
  • a lowering brake valve 15 In the right return line in the drawing, which with a lifting cylinder, not shown, of the working machine is connected there is a lowering brake valve 15.
  • the lowering brake valve 15 prevents a too fast Outflow of hydraulic oil into the tank 1 and is therefore suitable, for example the Braking lowering movement of a load suspension device.
  • left return line is a bias valve 16, with a certain predetermined pressure is maintained in the return line.
  • the directional valve block 8 the Lowering brake valve 15 and the preload valve 16 are arranged inside the tank 1. Leaks at these hydraulic components or at their connection points therefore do not lead to contamination of the working machine and its Environment with hydraulic fluid. Instead, the unintentionally emerging Hydraulic fluid caught in the tank.

Abstract

A work machine, especially an industrial truck, has a hydraulic plant that has at least one tank (1) for hydraulic fluid and at least one hydraulic pump (5). The hydraulic pump is located inside the tank. An electrical drive motor (3) of the hydraulic pump is located inside the tank. An electrical drive motor (3) of the hydraulic pump is located outside the tank and a shaft connecting the two is sealed with a shaft seal with respect to the tank. A priority valve is located inside the tank and is fastened by a flange connection to the hydraulic pump.

Description

Die Erfindung betrifft eine Arbeitsmaschine, insbesondere Flurförderzeug, mit einer hydraulischen Anlage, die mindestens einen Tank für Hydraulikfluid und mindestens eine Hydraulikpumpe aufweist.The invention relates to a work machine, in particular industrial truck, with a hydraulic system that has at least one tank for hydraulic fluid and at least has a hydraulic pump.

Arbeitsmaschinen sind häufig mit einer hydraulischen Anlage ausgerüstet, über welche in Abhängigkeit von der Bauart der Arbeitsmaschine der Antrieb verschiedener Funktionen der Arbeitsmaschine erfolgt. Bei Flurförderzeugen handelt es sich hierbei in der Regel um das Anheben und Neigen einer Last, um das Lenken des Flurförderzeugs sowie gegebenenfalls um Zusatzfunktionen zur Handhabung von Lasten.Working machines are often equipped with a hydraulic system, via which, depending on the construction of the machine, drives different Functions of the working machine is carried out. This is the case with industrial trucks usually about lifting and tilting a load, about steering the Industrial truck and possibly additional functions for handling Loads.

Die hydraulische Anlage weist in der Regel einen Tank auf, aus dem mittels einer Pumpe Hydraulikfluid angesaugt wird. Der Pumpe nachgeschaltet ist ein Prioritätsventil, das bevorzugt eine hydraulische Lenkungsvorrichtung mit Hydraulikfluid versorgt. Darüber hinaus wird Hydraulikfluid über willkürlich ansteuerbare Wegeventile weiteren hydraulischen Verbrauchern zur Verfügung gestellt. Hierbei handelt es sich meist um Hydraulikzylinder, mit denen die zum Anheben, Neigen oder Handhaben einer Last erforderlichen Kräfte erzeugt werden. Die Lenkungsvorrichtung und die anderen hydraulischen Verbraucher sind weiterhin über Rücklaufleitungen mit dem Tank verbunden, wobei in den Rücklaufleitungen gegebenenfalls eine Senkbremse zum Reduzieren der Durchflußmenge an Hydraulikfluid, oder ein Vorspannventil zum Aufrechterhalten eines vorgegebenen Druckniveaus in der entsprechenden Rücklaufleitung angeordnet sein kann.The hydraulic system usually has a tank, from which a Pump hydraulic fluid is sucked in. The pump is switched on Priority valve, which preferably has a hydraulic steering device Hydraulic fluid supplied. In addition, hydraulic fluid becomes over arbitrary controllable directional valves available to other hydraulic consumers posed. These are usually hydraulic cylinders with which to Lifting, tilting or handling a load required forces are generated. The steering device and the other hydraulic consumers are still connected to the tank via return lines, with in the return lines if necessary, a lowering brake to reduce the flow rate Hydraulic fluid, or a bias valve to maintain a predetermined Pressure levels can be arranged in the corresponding return line.

Die genannten hydraulischen Bauelemente sind bei Arbeitsmaschinen des Standes der Technik in der Regel voneinander getrennt an einem Rahmen der Arbeitsmaschine befestigt und über Schlauch- oder Rohrleitungen miteinander verbunden. Bekannt ist es ebenfalls, verschiedene hydraulische Bauelemente zu Baugruppen zusammenzufassen und gemeinsam an dem Rahmen der Arbeitsmaschine zu befestigen. In jedem Fall weisen bekannte hydraulische Anlagen jedoch eine Reihe von Trennfugen und Verbindungsstellen auf, die mit Dichtungen verschiedener Art gegen das Austreten von Hydraulikfluid abgedichtet werden.The hydraulic components mentioned are in the state of the art technology usually separated from each other on a frame of Work machine attached and with each other via hose or pipes connected. It is also known to different hydraulic components Summarize assemblies and together on the framework of the Attach work machine. In any case, known hydraulic systems however, a number of parting lines and junctions with seals various types are sealed against the leakage of hydraulic fluid.

Das Verhindern des Austretens von Hydraulikfluid aus der hydraulischen Anlage ist insbesondere aus Gründen des Arbeitsschutzes und Umweltschutzes geboten. Hierfür werden bei der Herstellung der Arbeitsmaschine erhebliche Mittel aufgewendet. Dennoch treten bei Arbeitsmaschinen immer wieder Undichtheiten der hydraulischen Anlage auf, die im Zuge von Reparatur- oder Wartungsarbeiten umgehend behoben werden müssen.Preventing hydraulic fluid from leaking from the hydraulic system offered in particular for reasons of occupational safety and environmental protection. This requires considerable resources in the manufacture of the machine spent. Nevertheless, leaks always occur in work machines hydraulic system in the course of repair or maintenance work must be remedied immediately.

Der vorliegenden Erfindung liegt die Aufgabe zugrunde, eine gattungsgemäße Arbeitsmaschine zur Verfügung zu stellen, bei der die Gefahr eines Austretens von Hydraulikfluid mit einfachen Mitteln verringert ist.The present invention has for its object a generic To provide work machine at which the risk of leakage from Hydraulic fluid is reduced with simple means.

Diese Aufgabe wird erfindungsgemäß dadurch gelöst, daß die Hydraulikpumpe innerhalb des Tanks angeordnet ist. Bei Undichtheiten eines Gehäuses der Hydraulikpumpe oder ihrer hydraulischen Anschlüsse fließt das austretende Hydrauliköl direkt in den Tank. Hierdurch wird eine Verschmutzung der Arbeitsmaschine und der Umgebung sicher verhindert. Ein Abdichten dieser undichten Stellen ist nur bei groben Beschädigungen der Dichtungselemente erforderlich, wenn das austretende Hydraulikfluid zu einem Leistungsverlust der hydraulischen Anlage führt. Kleinere Undichtheiten können im Zuge von regelmäßig stattfindenden Wartungsarbeiten behoben werden, da sie während des Betriebs der Arbeitsmaschine keine Gefahr für Betriebssicherheit und Umwelt darstellen. Ein weiterer Vorteil der Anordnung der Pumpe im Tank besteht darin, daß bei undichten Stellen in einem Ansaugbereich der Pumpe, beispielsweise an einem Ansaugrohr oder an einem Filter, ein Eintreten von Luft in die Hydraulikpumpe und damit eine Beschädigung infolge Kavitation vermieden wird.This object is achieved in that the hydraulic pump is arranged inside the tank. If there is a leak in the housing Hydraulic pump or its hydraulic connections flows the escaping Hydraulic oil directly into the tank. This will contaminate the Machine and the environment safely prevented. Sealing this up leaks are only in the case of gross damage to the sealing elements required if the escaping hydraulic fluid causes a loss of performance hydraulic system leads. Minor leaks can occur regularly maintenance work that is taking place must be remedied since it Work machine pose no danger to operational safety and the environment. On Another advantage of the arrangement of the pump in the tank is that in the event of leaks Places in a suction area of the pump, for example on an intake pipe or on a filter, entry of air into the hydraulic pump and thus one Damage due to cavitation is avoided.

Weitere Vorteile ergeben sich, wenn ein elektrischer Antriebsmotor der Hydraulikpumpe innerhalb des Tanks angeordnet ist. Es ist damit keine mechanische Drehdurchführung durch eine Wand des Tanks erforderlich. Das in dem Tank befindliche Hydraulikfluid dient darüber hinaus als Kühlmittel für den elektrischen Antriebsmotor. Die Anordnung des elektrischen Antriebsmotors innerhalb des Tanks bietet sich insbesondere an, wenn ein wartungsfreier Drehstrommotor eingesetzt wird. Further advantages result when an electric drive motor Hydraulic pump is arranged inside the tank. It is not a mechanical one Rotary feedthrough through a wall of the tank required. That in the tank hydraulic fluid is also used as a coolant for the electrical Drive motor. The arrangement of the electric drive motor inside the tank lends itself particularly well when a maintenance-free three-phase motor is used.

Wenn ein elektrischer Antriebsmotor der Hydraulikpumpe außerhalb des Tanks angeordnet ist, wird eine sichere Abdichtung erzielt, wenn eine den elektrischen Antriebsmotor mit der Hydraulikpumpe verbindende Welle gegenüber dem Tank mit einem Wellendichtring abgedichtet ist. Diese Anordnung bietet sich insbesondere bei der Verwendung eines Gleichstrommotors an, der für regelmäßig durchzuführende Wartungsarbeiten zugänglich sein muß.If an electric drive motor of the hydraulic pump is outside the tank is arranged, a secure seal is achieved when the electrical Drive motor with the hydraulic pump connecting shaft opposite the tank with a shaft seal is sealed. This arrangement is particularly useful for the use of a DC motor, which is recommended for regular use Maintenance work must be accessible.

Eine weitere Verbesserung hinsichtlich des Austretens von Hydraulikfluid ergibt sich, wenn ein Prioritätsventil innerhalb des Tanks angeordnet ist. Das Prioritätsventil stellt sicher, daß eine Lenkungsvorrichtung der Arbeitsmaschine jederzeit ausreichend mit Hydraulikfluid versorgt wird. Undichte Stellen im Bereich des Prioritätsventils, beispielsweise an den hydraulischen Anschlußstellen, führen bei dieser Anordnung nicht zu einer Verschmutzung der Umgebung durch Hydraulikfluid. Stattdessen wird das auslaufende Hydraulikfluid im Tank aufgefangen.A further improvement with regard to the leakage of hydraulic fluid results if a priority valve is located inside the tank. The priority valve provides sure that a steering device of the working machine is always sufficient Hydraulic fluid is supplied. Leaks in the area of the priority valve, for example at the hydraulic connection points, lead with this arrangement not to pollute the environment with hydraulic fluid. Instead it will the leaking hydraulic fluid is caught in the tank.

Wenn das Prioritätsventil mittels einer Flanschverbindung an der Hydraulikpumpe befestigt ist, sind zwischen diesen Bauteilen keine zusätzlichen hydraulischen Leitungen erforderlich. Hydraulikpumpe und Prioritätsventil können als vormontierte Baueinheit in den Tank eingebaut werden.If the priority valve by means of a flange connection on the hydraulic pump attached, there are no additional hydraulic between these components Lines required. Hydraulic pump and priority valve can be pre-assembled Unit to be installed in the tank.

Vorteilhaft ist es ebenfalls, wenn mindestens ein Wegeventil innerhalb des Tanks angeordnet ist. Mittels der Wegeventile wird die Zufuhr von Hydraulikfluid zu verschiedenen hydraulischen Verbrauchern in Abhängigkeit von einem von einer Bedienperson erzeugten Signal gesteuert. Leckagen dieser in der Regel proportional ansteuerbaren Wegeventile, die auch als Schieberventile ausgeführt sein können, werden vom Tank aufgefangen. Bei Schieberventilen kann auf die bei Geräten des Standes der Technik erforderliche aufwendige Tankrückführung des bauartbedingt anfallenden Leckageöls verzichtet werden. Es ist sogar möglich, auf die üblicherweise verwendeten Dichtungen gegen Verschmutzung der Schieberventile zu verzichten, da diese infolge der Anordnung im Tank keinen äußeren Einflüssen ausgesetzt sind. Darüber hinaus ist es möglich, auf eine Abdichtung der einzelnen Schieber der Wegeventile gegen Leckage zu verzichten, wodurch das Wegeventil preiswerter herstellbar ist. It is also advantageous if at least one directional control valve is located inside the tank is arranged. The supply of hydraulic fluid is blocked by means of the directional control valves different hydraulic consumers depending on one of one Operator generated signal controlled. Leakages of these are usually proportional controllable directional valves, which can also be designed as slide valves, are caught by the tank. In the case of slide valves, the devices in the State of the art required complex tank return due to the design resulting leakage oil can be dispensed with. It is even possible on the usual used seals against contamination of the slide valves, because due to the arrangement in the tank, they are not exposed to external influences. In addition, it is possible to seal the individual slider To dispense directional valves against leakage, which makes the directional valve cheaper can be produced.

Bei der Anordnung des Wegeventils im Tank ist es von Vorteil, wenn das Wegeventil elektrisch ansteuerbar ausgeführt ist. Die Wegeventile können damit räumlich unabhängig von dem jeweils zugeordneten Bedienhebel angeordnet werden.When arranging the directional control valve in the tank, it is advantageous if the directional control valve is electrically controllable. The directional control valves can thus be spatially be arranged independently of the respectively assigned control lever.

Zweckmäßigerweise sind mehrere Wegeventile vorgesehen, die einen Wegeventilblock bilden. Der Wegeventilblock kann vormontiert in den Tank eingebaut werden.Advantageously, several directional control valves are provided, one Form directional valve block. The directional valve block can be pre-assembled in the tank become.

Mit besonderem Vorteil ist das Prioritätsventil ein Bestandteil des Wegeventilblocks. Es sind somit auch keine hydraulischen Leitungen erforderlich, die das Prioritätsventil mit dem Wegeventilblock verbinden.The priority valve is a component of the directional valve block with particular advantage. There is therefore no need for hydraulic lines to connect the priority valve connect with the directional valve block.

Zu dem oben Erläuterten analoge Vorteile ergeben sich, wenn ein Lenkventil innerhalb des Tanks angeordnet ist.Analogous advantages to those explained above result when a steering valve is arranged inside the tank.

Zusätzlich kann auch das Lenkventil als Bestandteil des Wegeventilblocks ausgeführt sein.In addition, the steering valve can also be designed as part of the directional valve block his.

Zusätzliche Vorteile ergeben sich, wenn weitere hydraulische Bauelemente, beispielsweise ein oder mehrere Vorspannventile und/oder ein Senkbremsventil, innerhalb des Tanks angeordnet sind. Vorspannventil und Senkbremsventil sind in den Rücklaufleitungen von hydraulischen Verbrauchern angeordnet. Auch diese Bauelemente können erfindungsgemäß innerhalb des Tanks angeordnet werden.Additional advantages result if additional hydraulic components, for example one or more preload valves and / or a lowering brake valve, are arranged inside the tank. Preload valve and lowering brake valve are in arranged the return lines of hydraulic consumers. This too Components can be arranged according to the invention within the tank.

Weitere Vorteile und Einzelheiten der Erfindung werden anhand des in der schematischen Figur dargestellten Ausführungsbeispiels näher erläutert.Further advantages and details of the invention are shown in the schematic figure illustrated embodiment explained in more detail.

Die Figur zeigt einen Tank 1 einer hydraulischen Anlage einer Arbeitsmaschine. Der Tank 1 ist mit einer Tankhaube 2 dicht verschlossen. Innerhalb des Tanks 1 sind erfindungsgemäß eine Reihe von Bauteilen der hydraulischen Anlage angeordnet.The figure shows a tank 1 of a hydraulic system of a work machine. The Tank 1 is sealed with a tank hood 2. Are inside the tank 1 According to the invention, a number of components of the hydraulic system are arranged.

Ein als Drehstrommotor ausgeführter elektrischer Antriebsmotor 3 befindet sich unterhalb der Füllstandslinie 4 des Tanks 1 und wird somit von dem ihn umgebenden Hydraulikfluid gekühlt. An den Antriebsmotor 3 angeflanscht ist eine Hydraulikpumpe 5, die von dem Antriebsmotor 3 angetrieben wird. Die Hydraulikpumpe 5 saugt über einen Ansaugfilter 6, der in einem Saugrohr 7 angeordnet ist, Hydraulikfluid aus dem Tank 1 an.An electric drive motor 3 designed as a three-phase motor is located below the fill line 4 of the tank 1 and is thus from the surrounding Hydraulic fluid cooled. A hydraulic pump is flanged to the drive motor 3 5, which is driven by the drive motor 3. The hydraulic pump 5 sucks a suction filter 6, which is arranged in a suction pipe 7, hydraulic fluid from the Tank 1 on.

Im Bereich einer Ausgangsöffnung der Hydraulikpumpe 5 ist an die Hydraulikpumpe 5 ein Wegeventilblock 8 angeflanscht, der in diesem Ausführungsbeispiel ein Prioritätsventil 8a, ein Lenkventil 8b sowie zwei Wegeventile 8c, 8d umfaßt. Von dem Lenkventil 8b und den Wegeventilen 8c, 8d führen über eine Flanschplatte 10 hydraulische Druckleitungen 9 zu den jeweiligen hydraulischen Verbrauchern.The hydraulic pump 5 is connected to the hydraulic pump 5 in the area of an outlet opening a directional valve block 8 flanged, which in this embodiment Priority valve 8a, a steering valve 8b and two directional control valves 8c, 8d. Of the The steering valve 8b and the directional control valves 8c, 8d run over a flange plate 10 hydraulic pressure lines 9 to the respective hydraulic consumers.

In der Tankhaube 2 ist weiterhin eine Durchführung für elektrische Leitungen angeordnet. Hierbei sind eine Steuer- und Versorgungsleitung 11 für den elektrischen Antriebsmotor 3, sowie Signalleitungen 12 zu dem Lenkventil 8b und den Wegeventilen 8c, 8d vorgesehen. Die Signalleitungen sind mit den entsprechenden Bedienhebeln bzw. einem Lenkgeber verbunden, mit welchen elektrische Steuersignale erzeugt werden.In the tank hood 2 there is also a bushing for electrical lines arranged. Here are a control and supply line 11 for the electrical Drive motor 3, and signal lines 12 to the steering valve 8b and Directional control valves 8c, 8d are provided. The signal lines are with the corresponding ones Control levers or a steering sensor connected to which electrical Control signals are generated.

Dargestellt sind weiterhin zwei Rücklaufleitungen 13, durch welche Hydraulikfluid von den verschiedenen hydraulischen Verbrauchern in den Tank 1 zurückfließt. Die Rücklaufleitungen 13 werden über eine Flanschplatte 14 durch die Tankhaube 2 in den Tank 1 geführt. In der in der Zeichnung rechten Rücklaufleitung, welche mit einem nicht dargestellten Hubzylinder der Arbeitsmaschine verbunden ist, befindet sich ein Senkbremsventil 15. Das Senkbremsventil 15 verhindert ein zu schnelles Abströmen von Hydrauliköl in den Tank 1 und ist daher geeignet, beispielsweise die Absenkbewegung einer Lastaufnahmevorrichtung zu bremsen. In der in der Zeichnung linken Rücklaufleitung befindet sich ein Vorspannventil 16, mit dem ein bestimmter vorgegebener Druck in der Rücklaufleitung aufrechterhalten wird.Also shown are two return lines 13 through which hydraulic fluid from flows back to the various hydraulic consumers in tank 1. The Return lines 13 are via a flange plate 14 through the tank hood 2 in led the tank 1. In the right return line in the drawing, which with a lifting cylinder, not shown, of the working machine is connected there is a lowering brake valve 15. The lowering brake valve 15 prevents a too fast Outflow of hydraulic oil into the tank 1 and is therefore suitable, for example the Braking lowering movement of a load suspension device. In the in the Drawing left return line is a bias valve 16, with a certain predetermined pressure is maintained in the return line.

Erfindungsgemäß sind die Hydraulikpumpe 1, der Wegeventilblock 8, das Senkbremsventil 15 und das Vorspannventil 16 innerhalb des Tanks 1 angeordnet. Undichtheiten an diesen hydraulischen Bauteilen oder an ihren Verbindungsstellen führen daher nicht zu einer Verschmutzung der Arbeitsmaschine und deren Umgebung mit Hydraulikfluid. Stattdessen wird das ungewollt austretende Hydraulikfluid im Tank aufgefangen.According to the hydraulic pump 1, the directional valve block 8, the Lowering brake valve 15 and the preload valve 16 are arranged inside the tank 1. Leaks at these hydraulic components or at their connection points therefore do not lead to contamination of the working machine and its Environment with hydraulic fluid. Instead, the unintentionally emerging Hydraulic fluid caught in the tank.

Claims (12)

Arbeitsmaschine, insbesondere Flurförderzeug, mit einer hydraulischen Anlage, die mindestens einen Tank (1) für Hydraulikfluid und mindestens eine Hydraulikpumpe (5) aufweist, dadurch gekennzeichnet, daß die Hydraulikpumpe (5) innerhalb des Tanks (1) angeordnet ist.Working machine, in particular industrial truck, with a hydraulic system which has at least one tank (1) for hydraulic fluid and at least one hydraulic pump (5), characterized in that the hydraulic pump (5) is arranged inside the tank (1). Arbeitsmaschine nach Anspruch 1, dadurch gekennzeichnet, daß ein elektrischer Antriebsmotor (3) der Hydraulikpumpe (5) innerhalb des Tanks (1) angeordnet ist.Working machine according to claim 1, characterized in that an electric Drive motor (3) of the hydraulic pump (5) is arranged inside the tank (1). Arbeitsmaschine nach Anspruch 1, dadurch gekennzeichnet, daß ein elektrischer Antriebsmotor (3) der Hydraulikpumpe (5) außerhalb des Tanks (1) angeordnet ist, wobei eine den elektrischen Antriebsmotor (3) mit der Hydraulikpumpe (5) verbindende Welle gegenüber dem Tank (1) mit einem Wellendichtring abgedichtet ist.Working machine according to claim 1, characterized in that an electric Drive motor (3) of the hydraulic pump (5) arranged outside the tank (1) , one of which is the electric drive motor (3) with the hydraulic pump (5) connecting shaft opposite the tank (1) with a shaft seal is sealed. Arbeitsmaschine nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß ein Prioritätsventil (8a) innerhalb des Tanks (1) angeordnet ist.Working machine according to one of claims 1 to 3, characterized in that that a priority valve (8a) is arranged inside the tank (1). Arbeitsmaschine nach Anspruch 4, dadurch gekennzeichnet, daß das Prioritätsventil (8a) mittels einer Flanschverbindung an der Hydraulikpumpe (5) befestigt ist.Working machine according to claim 4, characterized in that the Priority valve (8a) by means of a flange connection on the hydraulic pump (5) is attached. Arbeitsmaschine nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß mindestens ein Wegeventil (8c, 8d) innerhalb des Tanks (1) angeordnet ist.Working machine according to one of claims 1 to 5, characterized in that that at least one directional valve (8c, 8d) is arranged inside the tank (1). Arbeitsmaschine nach Anspruch 6, dadurch gekennzeichnet, daß das Wegeventil (8c, 8d) elektrisch ansteuerbar ausgeführt ist.Working machine according to claim 6, characterized in that the directional valve (8c, 8d) is electrically controllable. Arbeitsmaschine nach Anspruch 6 oder 7, dadurch gekennzeichnet, daß mehrere Wegeventile (8c, 8d) vorgesehen sind, die einen Wegeventilblock (8) bilden.Working machine according to claim 6 or 7, characterized in that several Directional valves (8c, 8d) are provided which form a directional valve block (8). Arbeitsmaschine nach einem der Ansprüche 4 bis 8, dadurch gekennzeichnet, daß das Prioritätsventil (8a) ein Bestandteil des Wegeventilblocks (8) ist. Working machine according to one of claims 4 to 8, characterized in that that the priority valve (8a) is part of the directional valve block (8). Arbeitsmaschine nach einem der Ansprüche 1 bis 9, dadurch gekennzeichnet, daß ein Lenkventil (8b) innerhalb des Tanks (1) angeordnet ist.Working machine according to one of claims 1 to 9, characterized in that that a steering valve (8b) is arranged inside the tank (1). Arbeitsmaschine nach Anspruch 10, dadurch gekennzeichnet, daß das Lenkventil (8b) ein Bestandteil des Wegeventilblocks (8) ist.Working machine according to claim 10, characterized in that the steering valve (8b) is part of the directional valve block (8). Arbeitsmaschine nach einem der Ansprüche 1 bis 11, dadurch gekennzeichnet, daß weitere hydraulische Bauelemente, beispielsweise ein oder mehrere Vorspannventile (16) und/oder ein Senkbremsventil (15), innerhalb des Tanks (1) angeordnet sind.Working machine according to one of claims 1 to 11, characterized in that that further hydraulic components, for example one or more Preload valves (16) and / or a lowering brake valve (15), inside the tank (1) are arranged.
EP99123341A 1998-11-25 1999-11-23 Hydraulic system especially for an industrial truck Expired - Lifetime EP1004542B1 (en)

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DE19854417A DE19854417A1 (en) 1998-11-25 1998-11-25 Working machine, in particular industrial truck
DE19854417 1998-11-25

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1612418A1 (en) * 2004-07-03 2006-01-04 Jungheinrich Aktiengesellschaft Hydraulic unit for forklift truck
WO2009030793A1 (en) * 2007-08-27 2009-03-12 Romeral Cabeza, Angel Pressure-intensifying mechanism

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AUPP786598A0 (en) * 1998-12-23 1999-01-21 Jaden Charters Pty Ltd Improved skid-steer vehicle
DE20205936U1 (en) * 2002-04-16 2002-08-22 Trw Fahrwerksyst Gmbh & Co Hydraulic pump, in particular for a power steering system
FR2843601B1 (en) * 2002-08-13 2005-03-04 Rouby Ind DEVICE FOR MANEUVERING MECHANISMS ASSOCIATED WITH ECLUSES AND REGULATING RIVER FLOWS
US7185449B2 (en) * 2004-03-16 2007-03-06 Kime James A System for controlling the hydraulic actuated components of a truck
US8806862B2 (en) * 2007-12-20 2014-08-19 Parker-Hannifin Corporation Smart flow sharing system
TWI407019B (en) * 2010-07-30 2013-09-01 Wen Kwo Tien Automatic oil blocking hydraulic piping module
US20150247493A1 (en) * 2014-02-28 2015-09-03 Schlumberger Technology Corporation High pressure transfer motor-pump
US11339772B2 (en) * 2019-12-13 2022-05-24 Kti Hydraulics Inc. Hydraulic power units with submerged motors
EP4065851A4 (en) * 2019-12-14 2022-12-21 KTI Hydraulics Inc. Hydraulic power units with submerged motors
EP4239195A1 (en) * 2022-03-01 2023-09-06 Mathieu Hydraulic control unit

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1586186A (en) * 1968-09-06 1970-02-13
US4904162A (en) * 1986-01-17 1990-02-27 Mitsubishi Denki Kabushiki Kaisha Fuel supplying pump
DE19612582A1 (en) * 1996-03-29 1997-10-02 Miag Fahrzeugbau Gmbh Drive unit for vehicle e.g forklift truck

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3754394A (en) * 1971-12-02 1973-08-28 Hyster Co Hydraulic control system for electric lift truck
DE2337276A1 (en) * 1973-07-23 1975-02-06 Karl Hehl MACHINE BASE OF AN INJECTION MOLDING MACHINE
US3918683A (en) * 1974-01-09 1975-11-11 Daniel J Millar Electro-hydraulic jack
US4005636A (en) * 1975-02-13 1977-02-01 J. I. Case Company Hydraulic system for a working machine
US3988089A (en) * 1975-09-10 1976-10-26 The Goodyear Tire & Rubber Company Apparatus for manufacturing curved bodies of fiber reinforced plastic
DE2653102B1 (en) * 1976-11-23 1978-09-07 Hatlapa Uetersener Maschf Hydraulic winch
US4551973A (en) * 1982-10-28 1985-11-12 Syntex (U.S.A.) Inc. Hydraulic power source and valve therefor
DE3310702A1 (en) * 1983-03-24 1984-09-27 Allweiler Ag, 7760 Radolfzell Method and device for operating a hydraulic lift
US4773494A (en) * 1985-10-07 1988-09-27 Gene Anderson Hydraulically drive wheelchair
US4844197A (en) * 1986-07-14 1989-07-04 Western Atlas International, Inc. Hydraulic release system for use in a borehole apparatus
US5144801A (en) * 1989-04-28 1992-09-08 Parker Hannifin Corporation Electro-hydraulic actuator system
US5497621A (en) * 1994-11-10 1996-03-12 Fenner Fluid Power, A Division Of Fenner, Inc. Plastic reservoir

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1586186A (en) * 1968-09-06 1970-02-13
US4904162A (en) * 1986-01-17 1990-02-27 Mitsubishi Denki Kabushiki Kaisha Fuel supplying pump
DE19612582A1 (en) * 1996-03-29 1997-10-02 Miag Fahrzeugbau Gmbh Drive unit for vehicle e.g forklift truck

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1612418A1 (en) * 2004-07-03 2006-01-04 Jungheinrich Aktiengesellschaft Hydraulic unit for forklift truck
CN100343536C (en) * 2004-07-03 2007-10-17 容海因里希股份公司 Hydraulic unit for industrial trucks
WO2009030793A1 (en) * 2007-08-27 2009-03-12 Romeral Cabeza, Angel Pressure-intensifying mechanism

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DE19854417A1 (en) 2000-05-31
US6290474B1 (en) 2001-09-18
EP1004542B1 (en) 2006-01-25
DE59913077D1 (en) 2006-04-13

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