EP1780171B1 - Lift truck with a support leg arrangement - Google Patents
Lift truck with a support leg arrangement Download PDFInfo
- Publication number
- EP1780171B1 EP1780171B1 EP06021245A EP06021245A EP1780171B1 EP 1780171 B1 EP1780171 B1 EP 1780171B1 EP 06021245 A EP06021245 A EP 06021245A EP 06021245 A EP06021245 A EP 06021245A EP 1780171 B1 EP1780171 B1 EP 1780171B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- mast
- lifting
- hydraulic cylinders
- path difference
- pump
- 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.)
- Not-in-force
Links
- 230000001105 regulatory effect Effects 0.000 claims 4
- 238000005452 bending Methods 0.000 description 12
- 239000012530 fluid Substances 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 230000001419 dependent effect Effects 0.000 description 2
- 238000006073 displacement reaction Methods 0.000 description 2
- 230000005484 gravity Effects 0.000 description 2
- 239000003351 stiffener Substances 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
Images
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
-
- 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
- B66F9/08—Masts; Guides; Chains
Definitions
- the invention relates to a mast, in particular for a high-bay stacker according to claim 1.
- Height-adjustable masts are e.g. known as part of industrial trucks with high-lift equipment in a variety of designs. With the help of masts to be transported loads are recorded and stored at different altitudes, the lifting load is moved substantially vertically.
- Such a mast consists in principle of an outer frame in which moves directly a load-carrying means. Such a construction is relatively rare. In most cases, one or more driving masts move in the stationary mast. In a single and double telescopic mast, this is an inner mast. In a triple-telescopic mast, these are two, and in the quad telescopic mast, three inner masts.
- the individual mast frames consist of two lateral support profiles, which are connected at the top and bottom by transverse struts.
- the transmission of the bending load resulting from the lifting load is carried out between the nested mast frame normally via rollers, which are arranged at the top and bottom of the frame profiles.
- the drive for the height adjustment is usually by means of hydraulic lifting cylinders and chains that produce a relative movement between the mast frame.
- the construction of the mast frame is created so that the extended mast is rigid in its main load direction, so that it deforms as little as possible by the bending moment of a load at a higher altitude. Too much deformation leads to a shift of the center of gravity and thus to increase the force acting on the truck tipping moment. As a result, the stability of the vehicle is adversely affected.
- the necessary bending stiffness is achieved by selecting lifting frame profiles with reasonably large moments of inertia.
- a lateral bending In addition to the main bending load can also occur a lateral bending, which is caused by an eccentric center of gravity of the lifting load or by dynamic lateral mass forces. Due to the resulting lateral bending of the mast, the lateral Hublasthebelarm is increased and thus increases the lateral tilting moment.
- the rigidity of the mast frame with respect to lateral bending is usually achieved by connecting the two lateral support profiles of the mast frame by massive transverse stiffeners (ladder-shaped). These transverse stiffeners obstruct the view through the mast frame and increase its weight.
- Out EP 1 528 035 A2 It is known to monitor the inclination of a mast from a position sensor and to control the pressure in the hydraulic cylinders so that the inclination is compensated.
- Out DD 30489 It has become known to control the amount of fluid to the lifting cylinders of a lifting mast load-dependent.
- the invention has for its object to provide a mast, especially for a high-bay stacker, in which a lateral bending is prevented from the outset.
- a control device for the two linear actuators is provided, with which a path difference of the stroke of the linear actuators is measured and the linear actuators are controlled so that the path difference remains zero.
- the supply of equal volumes of pressure medium is ensured by a quantity divider are arranged between the hydraulic pressure source and the hydraulic cylinders, via which the hydraulic cylinders are each supplied with the same pressure medium volume.
- Hydraulic flow dividers do not work well in practice, so that the same stroke on the hydraulic cylinders can not be guaranteed completely safe. Because the pressure medium is compressible to some extent, and in the piping system compliances of the pressure medium-carrying parts are present, such as in pipes and hoses. For practical applications, such flow divider can work satisfactorily.
- Downstream of the flow divider are the lines to the hydraulic cylinders on one in the speed controllable pump are connected and the pump is driven at a path difference of the hydraulic cylinder or an inclination angle of the mast from a motor, wherein the direction of rotation of the motor is dependent on the sign of the path difference or the inclination angle.
- the speed and conveying direction of the pump are predetermined by an electronic control, which measures the travel of each lifting cylinder or the inclination angle of the mast with a sensor device.
- a throttle can be connected in parallel to the equalizing pump, which ensures that the pump is not operated at unacceptably low speeds.
- a shut-off valve can be provided in series with the balance pump, which is opened only during operation of the balance pump. In case of failure of the balancing pump, this valve is closed, so that a pressure compensation and thus a loss of stabilizing effect is avoided. In the case of a path difference or an inclination angle from the lifting mast, the compensating pump is then activated in such a way that the path difference or the angle of inclination is minimized.
- dynamic deformations such as e.g. When cornering the truck occur, to reduce within certain limits.
- a controllable three / three-way valve with two input ports is located on the master cylinder, while an output port is connected to the tank.
- the control device controls in accordance with the path difference or the inclination angle, the valve so that one of the two hydraulic cylinders is connected to the tank.
- a possible difference in the stroke of the Hydraulic cylinder is compensated by allowing fluid to flow into the tank through the valve until the stroke of both cylinders is equal again.
- each lifting cylinder is associated with a controllable lifting / lowering valve, which are located at the output of a hydraulic pump and the control device in accordance with the path difference or the inclination angle of one of the two lifting / lowering valves so controls that the path difference or the inclination angle becomes zero, respectively.
- Fig. 1 schematically shown a mast, with a stationary mast frame 10, which can be attached to a high-bay forklift.
- a stationary mast frame 10 which can be attached to a high-bay forklift.
- two hydraulic cylinders 14, 16 are based, which are connected to an upper cross member 18 of a mast frame 20.
- arrows 22 and 24 different lifting forces are to be indicated, which lead to a lateral bending moment 26. In the embodiments described below, a deflection is to be prevented despite a bending moment generated by the load.
- Fig. 2 can be seen that the hydraulic cylinders 14, 16 are supplied via a so-called flow or flow divider 30 with pressure medium.
- the flow divider ensures that both hydraulic cylinders 14, 16 regardless of their load in each case the same pressure medium volume is supplied, so that the hydraulic cylinders 14, 16 execute the same stroke paths.
- Fig. 3 the hydraulic cylinders 14, 16 are connected via the flow divider 30 to a hydraulic pump.
- a parallel connection 32 between the supply lines to the hydraulic cylinders 14, 16 is provided, in which a small controllable pump 34 is arranged, which is driven by an electric motor 36.
- Parallel to the pump 34 is a throttle 38.
- the circuit arrangement shown operates as follows.
- the flow divider 30 should ensure that the hydraulic cylinders 14, 16 are each supplied with equal volumes. For various reasons, this is not always guaranteed.
- a sensor device not shown measures the strokes of the hydraulic cylinders 14, 16. At a difference between the measured strokes, the electric motor 36 is driven and drives the pump 34 in one direction so that the measured path difference is made zero. Once the path difference is zero, the motor 36 is turned off. During this Operation, the valve 40 is opened, which is otherwise closed when the pump 34 is not operating, in order not to jeopardize the uniform supply of the hydraulic cylinders 14, 16 via the flow divider 30 in case of failure of the pump 34.
- the throttle 38 ensures that the pump is not operated at impermissibly low speeds.
- a fault of the flow divider 30 can be compensated by means of a three / three-way valve 42, the two inputs are respectively connected to the hydraulic cylinders 14, 16 and whose output is connected to a tank 44. With a stroke difference, the valve 42 is opened, so that one of the two hydraulic cylinders 14, 16 as long pressure fluid is discharged into the tank 44 until the stroke of both cylinders is equal again.
- the required regulation corresponds to that according to Fig. 4 ,
- each hydraulic cylinder 14, 16 is associated with a lifting and lowering valve 46, 48, which are driven by an electronic unit, not shown. With the help of a sensor, which is not shown, the stroke paths of the hydraulic cylinders 14, 16 are measured.
- the control of the valves 46, 48 via the control device is such that the supply of pressure medium from a pump 50 is different until the Hubwegdifferenz has become zero again.
Landscapes
- Engineering & Computer Science (AREA)
- Transportation (AREA)
- Structural Engineering (AREA)
- Civil Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Forklifts And Lifting Vehicles (AREA)
Description
Die Erfindung bezieht sich auf einen Hubmast, insbesondere für einen Hochregalstapler nach dem Patentanspruch 1.The invention relates to a mast, in particular for a high-bay stacker according to claim 1.
Höhenverstellbare Hubgerüste sind z.B. als Bestandteil von Flurförderzeugen mit Hochhubeinrichtungen in den unterschiedlichsten Konstruktionsformen bekannt. Mit Hilfe der Hubgerüste sollen zu transportierende Lasten in unterschiedlichen Höhenlagen aufgenommen und abgelegt werden, wobei die Hublast im Wesentlichen vertikal bewegt wird.Height-adjustable masts are e.g. known as part of industrial trucks with high-lift equipment in a variety of designs. With the help of masts to be transported loads are recorded and stored at different altitudes, the lifting load is moved substantially vertically.
Ein derartiges Hubgerüst besteht im Prinzip aus einem äußeren Standrahmen, in dem sich unmittelbar ein Lastaufnahmemittel bewegt. Eine derartige Konstruktion ist relativ selten. In den meisten Fällen bewegen sich im Standmast ein oder mehrere Fahrmaste. Bei einem Einfach- und Zweifach-Teleskop-Hubgerüst ist das ein innerer Fahrmast. Bei einem Dreifach-Teleskop-Hubgerüst sind das zwei, und beim Vierfach-Teleskop-Hubgerüst drei innere Fahrmaste.Such a mast consists in principle of an outer frame in which moves directly a load-carrying means. Such a construction is relatively rare. In most cases, one or more driving masts move in the stationary mast. In a single and double telescopic mast, this is an inner mast. In a triple-telescopic mast, these are two, and in the quad telescopic mast, three inner masts.
Die einzelnen Mastrahmen bestehen aus zwei seitlichen Tragprofilen, die oben und unten durch Querstreben verbunden sind. Die Übertragung des aus der Hublast resultierenden Biegemoments erfolgt zwischen den ineinander verschachtelten Mastrahmen normalerweise über Laufrollen, die am oberen und unteren Ende der Rahmenprofile angeordnet sind. Der Antrieb für die Höhenverstellung erfolgt zumeist mittels hydraulischer Hubzylinder und Ketten, die eine Relativbewegung zwischen den einzelnen Mastrahmen erzeugen.The individual mast frames consist of two lateral support profiles, which are connected at the top and bottom by transverse struts. The transmission of the bending load resulting from the lifting load is carried out between the nested mast frame normally via rollers, which are arranged at the top and bottom of the frame profiles. The drive for the height adjustment is usually by means of hydraulic lifting cylinders and chains that produce a relative movement between the mast frame.
Die Konstruktion der Mastrahmen ist so geschaffen, dass das ausgefahrene Hubgerüst in seiner Hauptbelastungsrichtung biegesteif ist, damit es sich durch das Biegemoment einer in größerer Höhe befindlichen Last möglichst wenig verformt. Eine zu große Verformung führt zu einer Verschiebung des Lastschwerpunkts und damit zur Vergrößerung des auf das Flurförderzeug wirkende Kippmoments. Dadurch wird die Standsicherheit des Fahrzeugs negativ beeinflußt. Die notwendige Biegesteifigkeit wird durch die Auswahl von Hubrahmenprofilen mit angemessen großen Flächenträgheitsmomenten erreicht.The construction of the mast frame is created so that the extended mast is rigid in its main load direction, so that it deforms as little as possible by the bending moment of a load at a higher altitude. Too much deformation leads to a shift of the center of gravity and thus to increase the force acting on the truck tipping moment. As a result, the stability of the vehicle is adversely affected. The necessary bending stiffness is achieved by selecting lifting frame profiles with reasonably large moments of inertia.
Neben der Hauptbiegebelastung kann auch eine seitliche Biegung auftreten, die durch eine exzentrische Schwerpunktlage der Hublast oder durch dynamische seitliche Massenkräfte hervorgerufen wird. Durch die resultierende seitliche Verbiegung des Hubmastes wird der seitliche Hublasthebelarm vergrößert und damit auch das seitliche Kippmoment erhöht. Die Steifigkeit der Hubmastrahmen gegenüber seitlicher Verbiegung wird üblicherweise dadurch erreicht, dass die beiden seitlichen Tragprofile des Hubmastrahmens durch massive Querversteifungen (leiterförmig) verbunden werden. Diese Querversteifungen behindern die Sicht durch den Hubmastrahmen und vergrößern sein Gewicht.In addition to the main bending load can also occur a lateral bending, which is caused by an eccentric center of gravity of the lifting load or by dynamic lateral mass forces. Due to the resulting lateral bending of the mast, the lateral Hublasthebelarm is increased and thus increases the lateral tilting moment. The rigidity of the mast frame with respect to lateral bending is usually achieved by connecting the two lateral support profiles of the mast frame by massive transverse stiffeners (ladder-shaped). These transverse stiffeners obstruct the view through the mast frame and increase its weight.
Aus
Aus
In
Aus
Aus
Aus
Aus
Der Erfindung liegt die Aufgabe zugrunde, einen Hubmast, insbesondere für einen Hochregalstapler, zu schaffen, bei dem eine seitliche Verbiegung von vornherein verhindert wird.The invention has for its object to provide a mast, especially for a high-bay stacker, in which a lateral bending is prevented from the outset.
Diese Aufgabe wird durch die Merkmale des Patentanspruchs 1 gelöst.This object is solved by the features of patent claim 1.
Bei der Erfindung nach Patentanspruch 1 ist eine Regelvorrichtung für die beiden Hubantriebe vorgesehen, mit der eine Wegdifferenz der Hubwege der Hubantriebe gemessen wird und die Hubantriebe so gesteuert werden, dass die Wegdifferenz Null bleibt.In the invention according to claim 1, a control device for the two linear actuators is provided, with which a path difference of the stroke of the linear actuators is measured and the linear actuators are controlled so that the path difference remains zero.
Bei der Erfindung nach Anspruch 4 ist die Zufuhr gleicher Druckmittel-Volumina gewährleistet, indem zwischen der Hydraulikdruckquelle und den Hydraulikzylindern ein Mengenteiler angeordnet werden, über den die Hydraulikzylinder jeweils mit gleichen Druckmittelvolumen versorgt werden. Hydraulische Stromteiler arbeiten in der Praxis nicht ideal, sodass der gleiche Hubweg an den hydraulischen Zylindern nicht vollständig sicher gewährleistet werden kann. Denn das Druckmittel ist in gewissem Maße kompressibel, und im Leitungssystem sind Nachgiebigkeiten der druckmittel führenden Teile vorhanden, etwa in Rohren und Schläuchen. Für praktische Anwendungen können derartige Mengenteiler zufriedenstellend arbeiten.In the invention according to claim 4, the supply of equal volumes of pressure medium is ensured by a quantity divider are arranged between the hydraulic pressure source and the hydraulic cylinders, via which the hydraulic cylinders are each supplied with the same pressure medium volume. Hydraulic flow dividers do not work well in practice, so that the same stroke on the hydraulic cylinders can not be guaranteed completely safe. Because the pressure medium is compressible to some extent, and in the piping system compliances of the pressure medium-carrying parts are present, such as in pipes and hoses. For practical applications, such flow divider can work satisfactorily.
Abströmseitig vom Mengenteiler sind die Leitungen zu den Hydraulikzylindern über eine in der Drehzahl regelbare Pumpe verbunden sind und die Pumpe ist bei einer Wegdifferenz der Hydraulikzylinder oder einem Neigungswinkel des Hubmastes von einem Motor angetrieben wird, wobei die Drehrichtung des Motors vom Vorzeichen der Wegdifferenz bzw. des Neigungswinkels abhängig ist. Die Drehzahl und Förderrichtung der Pumpe werden von einer elektronischen Steuerung vorgegeben, die mit einer Sensoreinrichtung den Weg jedes Hubzylinders bzw. den Neigungswinkel des Mastes mißt. Nach einer Ausgestaltung der Erfindung kann parallel zur Ausgleichspumpe eine Drossel geschaltet werden, die gewährleistet, dass die Pumpe nicht mit unzulässig niedrigen Drehzahlen betrieben wird.Downstream of the flow divider are the lines to the hydraulic cylinders on one in the speed controllable pump are connected and the pump is driven at a path difference of the hydraulic cylinder or an inclination angle of the mast from a motor, wherein the direction of rotation of the motor is dependent on the sign of the path difference or the inclination angle. The speed and conveying direction of the pump are predetermined by an electronic control, which measures the travel of each lifting cylinder or the inclination angle of the mast with a sensor device. According to one embodiment of the invention, a throttle can be connected in parallel to the equalizing pump, which ensures that the pump is not operated at unacceptably low speeds.
Nach einer weiteren Ausgestaltung der Erfindung kann in Reihe mit der Ausgleichspumpe ein Abschaltventil vorgesehen werden, das nur bei Betrieb der Ausgleichspumpe geöffnet wird. Bei Ausfall der Ausgleichspumpe wird dieses Ventil geschlossen, sodass ein Druckausgleich und damit ein Verlust der stabilisierenden Wirkung vermieden wird. Bei einer Wegdifferenz bzw. einem Neigungswinkel vom Hubmast wird die Ausgleichspumpe dann so angesteuert, dass die Wegdifferenz bzw. der Neigungswinkel minimiert wird. Mit Hilfe einer derartigen Anordnung ist es auch möglich, dynamische Verformungen, wie sie z.B. bei Kurvenfahrten des Flurförderzeugs auftreten, in gewissen Grenzen zu reduzieren.According to a further embodiment of the invention, a shut-off valve can be provided in series with the balance pump, which is opened only during operation of the balance pump. In case of failure of the balancing pump, this valve is closed, so that a pressure compensation and thus a loss of stabilizing effect is avoided. In the case of a path difference or an inclination angle from the lifting mast, the compensating pump is then activated in such a way that the path difference or the angle of inclination is minimized. By means of such an arrangement, it is also possible to use dynamic deformations such as e.g. When cornering the truck occur, to reduce within certain limits.
Nach einer weiteren Ausgestaltung der Erfindung ist vorgesehen, dass parallel zum Mengenteiler ein steuerbares Drei/Dreiwege-Ventil mit zwei Eingangsanschlüssen an dem Hauptzylinder liegt, während ein Ausgangsanschluß an den Tank angeschlossen ist. Die Regelvorrichtung steuert nach Maßgabe der Wegdifferenz bzw. des Neigungswinkels das Ventil so an, dass einer der beiden Hydraulikzylinder mit dem Tank verbunden wird. Ein eventueller Unterschied im Hubweg der Hydraulikzylinder wird dadurch ausgeglichen, dass über das Ventil so lange Fluid in den Tank gelassen wird, bis der Hubweg beider Zylinder wieder gleich ist.According to a further embodiment of the invention it is provided that parallel to the flow divider a controllable three / three-way valve with two input ports is located on the master cylinder, while an output port is connected to the tank. The control device controls in accordance with the path difference or the inclination angle, the valve so that one of the two hydraulic cylinders is connected to the tank. A possible difference in the stroke of the Hydraulic cylinder is compensated by allowing fluid to flow into the tank through the valve until the stroke of both cylinders is equal again.
Eine andere Ausgestaltung der Erfindung sieht schließlich vor, dass jedem Hubzylinder ein steuerbares Hub-/Senkventil zugeordnet ist, die am Ausgang einer Hydraulikpumpe liegen und die Regelvorrichtung nach Maßgabe der Wegdifferenz oder des Neigungswinkels eines der beiden Hub-/Senkventile so ansteuert, dass die Wegdifferenz oder der Neigungswinkel jeweils zu null wird.Another embodiment of the invention finally provides that each lifting cylinder is associated with a controllable lifting / lowering valve, which are located at the output of a hydraulic pump and the control device in accordance with the path difference or the inclination angle of one of the two lifting / lowering valves so controls that the path difference or the inclination angle becomes zero, respectively.
Die Erfindung wird nachfolgend anhand von Zeichnungen näher erläutert:
- Fig. 1
- zeigt einen Hubmast, wie er mit einer erfindungsgemäßen Vorrichtung ausgestattet werden kann.
- Fig. 2
- zeigt eine erste Ausführungsform nach der Erfindung.
- Fig. 3
- zeigt eine zweite Ausführungsform nach der Erfindung.
- Fig. 4
- zeigt eine dritte Ausführungsform nach der Erfindung.
- Fig. 5
- zeigt eine vierte Ausführungsform nach der Erfindung.
- Fig. 1
- shows a mast, as it can be equipped with a device according to the invention.
- Fig. 2
- shows a first embodiment of the invention.
- Fig. 3
- shows a second embodiment of the invention.
- Fig. 4
- shows a third embodiment of the invention.
- Fig. 5
- shows a fourth embodiment of the invention.
In
In
In
An sich soll der Stromteiler 30 dafür sorgen, dass den Hydraulikzylindern 14, 16 jeweils gleiche Volumina zugeführt werden. Aus verschiedenen Gründen ist dies aber nicht immer gewährleistet. Eine nicht gezeigte Sensorvorrichtung mißt die Hubwege der Hydraulikzylinder 14, 16. Bei einer Differenz zwischen den gemessenen Hubwegen wird der Elektromotor 36 angesteuert und treibt die Pumpe 34 in einer Richtung so an, dass die gemessene Wegdifferenz zu null gemacht wird. Sobald die Wegdifferenz null ist, wird der Motor 36 ausgeschaltet. Während dieses Vorgangs ist das Ventil 40 geöffnet, das ansonsten bei Nichtbetrieb der Pumpe 34 geschlossen ist, um bei einem Ausfall der Pumpe 34 nicht die gleichmäßige Versorgung der Hydraulikzylinder 14, 16 über den Stromteiler 30 zu gefährden. Die Drossel 38 gewährleistet, dass die Pumpe nicht mit unzulässig niedrigen Drehzahlen betrieben wird.In itself, the
Statt einer Messung der Wegdifferenz der Hubwege der Hydraulikzylinder 14, 16 kann auch der Neigungswinkel gemessen werden, der mit Hilfe der beschriebenen Maßnahme bei einem Wert ungleich null wieder minimiert oder zu null gemacht wird.Instead of measuring the path difference of the stroke paths of the
Bei der Ausführungsform nach
Bei der Ausführungsform nach
Claims (8)
- A lifting mast, in particular for a high-bay stacker lift truck, having a fixed mast and at least one extendable mast section with two parallel lift drives arranged laterally on the mast for extending the mast section from the fixed mast and a control for the lift drives, characterized in that a regulating device is provided for the two lift drives for measuring a path difference in the lifting paths of the lift drives and the lift drives are controlled such that the path difference remains zero.
- The lifting mast according to claim 1, characterized in that the lift drives have two motors, each driving a spindle drive, and the path difference is determined by measuring the angle of rotation of the spindle drives.
- The lifting mast according to claim 1, characterized in that the lift drives are disposed on hydraulic cylinders (14, 16) connectable to a hydraulic source and the supply of displaced volume to the hydraulic cylinders (14, 16) is controlled such that the lifting paths of the hydraulic cylinders (14, 16) are equal.
- A lifting mast, in particular for a high-bay stacker lift truck, having a fixed mast and at least one extendable mast section with two parallel hydraulic cylinders arranged laterally for extending the mast section from the fixed mast and a control for the hydraulic cylinders, characterized in that a volume or flow divider (30) is disposed between the hydraulic pressure sources and the hydraulic cylinders (14, 16), by means of which the hydraulic cylinders (14, 16) are supplied with the same volume of pressurizing medium and that the lines to the hydraulic cylinders (14, 16) are connected on the outflow side of a volume or flow divider (30) via a pump (34) regulated in its rotational speed and the pump (34) is driven by a motor (36) upon a path difference of the hydraulic cylinders (14, 16) or an angle of inclination of the lifting mast, wherein the rotational direction of the motor (36) is a prognostic function of the path difference, the angle of inclination respectively.
- The lifting mast according to claim 4, characterized in that a restrictor (38) is connected in parallel to the pump (34).
- The lifting mast according to claim 4 or 5, characterized in that a control valve (40) is disposed in the connecting line between the lines, which is normally closed, although opened when pump (34) is in operation.
- The lifting mast according to claim 3 or 4, characterized in that a controllable triple/three-way valve with two input connections to the hydraulic cylinders (14, 16) is disposed parallel to the volume or flow divider (30), while an output connection connects to the tank (44) and the regulating device controls the valve (42) based on the path difference or angle of inclination such that one of the two hydraulic cylinders (14, 16) is connected to the tank (44).
- The lifting mast according to claim 3, characterized in that each hydraulic cylinder (14, 16) is assigned a controllable lifting/lowering valve (46, 48) disposed at the outlet of a hydraulic pump (50) and the regulating device controls one of the two lifting/lowering valves (46, 48) based on the path difference such that the path difference will be zero.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
DE102005050733A DE102005050733A1 (en) | 2005-10-22 | 2005-10-22 | Lifting mast for shelf stacking truck has fixed mast with movable mast controlled by measuring mast deflection and regulating side mounted drives |
Publications (3)
Publication Number | Publication Date |
---|---|
EP1780171A2 EP1780171A2 (en) | 2007-05-02 |
EP1780171A3 EP1780171A3 (en) | 2007-06-06 |
EP1780171B1 true EP1780171B1 (en) | 2013-02-20 |
Family
ID=37831746
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP06021245A Not-in-force EP1780171B1 (en) | 2005-10-22 | 2006-10-10 | Lift truck with a support leg arrangement |
Country Status (4)
Country | Link |
---|---|
US (1) | US20070089934A1 (en) |
EP (1) | EP1780171B1 (en) |
CN (1) | CN1994855B (en) |
DE (1) | DE102005050733A1 (en) |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE102007042878A1 (en) | 2007-09-08 | 2009-03-12 | Jungheinrich Aktiengesellschaft | Hochhubflurförderzeug |
EP2465812B1 (en) * | 2010-12-16 | 2013-11-06 | BT Products AB | Industrial truck comprising an extendable mast |
CN103288008A (en) * | 2012-02-26 | 2013-09-11 | 吴涛慧 | Loading and unloading vehicle with long roll shaft |
CN104595480B (en) * | 2015-01-05 | 2018-06-08 | 安徽维麦重工股份有限公司 | A kind of internal combustion hydraulic fork lift is driven safety-restraint system |
DE102017121818A1 (en) | 2017-09-20 | 2019-03-21 | Jungheinrich Ag | Industrial truck, hydraulic system for an industrial truck and method for operating a hydraulic system |
Family Cites Families (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DD30489A (en) * | ||||
US3782503A (en) * | 1972-12-14 | 1974-01-01 | Anderson Clayton & Co | Mast stabilizer for lift trucks |
WO1981003014A1 (en) * | 1980-04-14 | 1981-10-29 | Towmotor Corp | Load lifting carriage and mast assembly |
US4337959A (en) * | 1980-06-05 | 1982-07-06 | International Harvester Co. | Self-leveling and height control hydraulic system |
US4335894A (en) * | 1980-06-05 | 1982-06-22 | International Harvester Co. | Implement level lift system with rephasing valves |
US4395189A (en) * | 1981-02-02 | 1983-07-26 | Munten Gerard H | Dual mast lift truck for unbalanced loads and the like |
IT1187790B (en) * | 1985-06-24 | 1987-12-23 | Corghi Elettromecc Spa | HYDRAULIC CONTROL SYSTEM FOR LIFT BRIDGES OF VEHICLES IN GENERAL |
US4782920A (en) * | 1987-02-04 | 1988-11-08 | Cascade Corporation | Load-lifting mast especially adapted for use with automatically-guided vehicles |
SE469485B (en) * | 1991-11-29 | 1993-07-12 | Jan Lindholm | PROCEDURE AND FLOW CONTROL VALVE STREAM FOR FLOW BALANCE |
NL9200589A (en) * | 1992-03-30 | 1993-10-18 | Meijer Sjoerd | HYDRAULIC DEVICE WITH SIMILAR AUGERS. |
US5335499A (en) * | 1992-09-24 | 1994-08-09 | Viking Engineering & Development, Incorporated | Multiple hydraulic actuators with series/parallel operation |
FR2749630B1 (en) * | 1996-06-07 | 1998-10-09 | Lohr Ind | DEVICE FOR MANEUVERING A CARRIER STRUCTURE FROM A TORQUE OF SCREWS EACH CARRYING A TRANSLATION NUT |
CN2291407Y (en) * | 1996-11-22 | 1998-09-16 | 刘水章 | Double hydraulic motor driving device for electric balanced heavy-duty fork-lift truck |
EP0866027B1 (en) * | 1997-03-21 | 2004-05-26 | Kabushiki Kaisha Toyota Jidoshokki | Hydraulic control apparatus for industrial vehicles |
JPH11171492A (en) * | 1997-12-15 | 1999-06-29 | Toyota Autom Loom Works Ltd | Industrial vehicular data setting device and industrial vehicle |
US6189432B1 (en) * | 1999-03-12 | 2001-02-20 | Hunter Engineering Company | Automotive lift hydraulic fluid control circuit |
GB2387372B (en) * | 2002-04-10 | 2005-06-29 | Lansing Linde Ltd | Industrial truck |
DE10321487A1 (en) * | 2003-05-13 | 2004-12-02 | Still Wagner Gmbh & Co. Kg | Thrust mast stacker for placing loads into and out of shelves, has actuators that define position of multi-lift in longitudinal direction and inclination of multi-lift relative to slope axis |
DE10342436B3 (en) * | 2003-09-11 | 2005-03-17 | Jungheinrich Ag | Pump unit for manual fork lift truck has three-stage control valve with three no-return valves and switching valve |
DE10349123A1 (en) * | 2003-10-22 | 2005-05-19 | Still Wagner Gmbh & Co Kg | Hoist, especially for a high rack forklift |
-
2005
- 2005-10-22 DE DE102005050733A patent/DE102005050733A1/en not_active Ceased
-
2006
- 2006-10-10 EP EP06021245A patent/EP1780171B1/en not_active Not-in-force
- 2006-10-19 US US11/583,957 patent/US20070089934A1/en not_active Abandoned
- 2006-10-20 CN CN2006100641970A patent/CN1994855B/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
US20070089934A1 (en) | 2007-04-26 |
EP1780171A2 (en) | 2007-05-02 |
CN1994855A (en) | 2007-07-11 |
DE102005050733A1 (en) | 2007-04-26 |
CN1994855B (en) | 2013-11-13 |
EP1780171A3 (en) | 2007-06-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP2039582B1 (en) | Active hydraulic damper and hydraulic actuator | |
DE69221122T2 (en) | LIFTING MACHINE WITH SELF-DRIVE AND WITH NON-CONNECTED DOCUMENTS | |
DE102007001510B4 (en) | Hydraulic system with multiple pressure relief levels | |
EP0546300B1 (en) | Electrohydraulic control system | |
EP0936179B1 (en) | Forklift control arrangement | |
DE112017003054T5 (en) | HYDRAULIC CONTROL SYSTEM | |
EP1780171B1 (en) | Lift truck with a support leg arrangement | |
DE112012005636T5 (en) | Drive system for closed hydraulic circuit | |
EP1024109B1 (en) | Attachment for industrial trucks with a mast, in particular for forklift-trucks | |
EP3336050B1 (en) | Industrial truck with a control unit for regulating the movement of a piston rod of a hydraulic cylinder and such a method | |
EP2142808B1 (en) | Hydraulic control arrangement | |
EP1967485B1 (en) | Industrial truck | |
EP2404493B1 (en) | Hoisting gear | |
EP0489230B1 (en) | Lifting mast, especially for lift trucks | |
EP3936470B1 (en) | Hydraulic lift drive for a mobile working machine | |
EP0229330B1 (en) | Swing gear driven by two separate cylinder-crank mechanisms | |
EP1576241B1 (en) | Control device for a work device comprising a scoop held on an extension arm | |
DE10007688A1 (en) | Device for controlling the tilting function of a mast, in particular for a forklift | |
DE4219787C1 (en) | Vehicle with a battery-electric drive, especially a rear loader | |
DE19819270B4 (en) | Sideloader | |
DE102010048890A1 (en) | Hydrostatic drive system of mobile working machine e.g. industrial truck, has fan drive that is controlled by directional control valve having pressure balance | |
DE102010048891A1 (en) | Drive system for mobile machine, particularly ground conveyor, has hydraulic fan drive for producing cooling air flow at heat exchanger unit | |
DE102016216863A1 (en) | Boost function for lifting device | |
DE102017107365A1 (en) | Hydraulic lifting drive of a mobile work machine, especially an industrial truck | |
EP3786104A1 (en) | Method for controlling a hydraulic function of an industrial truck |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Kind code of ref document: A2 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL BA HR MK YU |
|
PUAL | Search report despatched |
Free format text: ORIGINAL CODE: 0009013 |
|
AK | Designated contracting states |
Kind code of ref document: A3 Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR |
|
AX | Request for extension of the european patent |
Extension state: AL BA HR MK YU |
|
RTI1 | Title (correction) |
Free format text: LIFT TRUCK WITH A SUPPORT LEG ARRANGEMENT |
|
17P | Request for examination filed |
Effective date: 20071204 |
|
AKX | Designation fees paid |
Designated state(s): DE FR GB IT |
|
17Q | First examination report despatched |
Effective date: 20090622 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAP | Despatch of communication of intention to grant a patent |
Free format text: ORIGINAL CODE: EPIDOSNIGR1 |
|
GRAS | Grant fee paid |
Free format text: ORIGINAL CODE: EPIDOSNIGR3 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
RAP1 | Party data changed (applicant data changed or rights of an application transferred) |
Owner name: JUNGHEINRICH AKTIENGESELLSCHAFT |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): DE FR GB IT |
|
REG | Reference to a national code |
Ref country code: GB Ref legal event code: FG4D Free format text: NOT ENGLISH |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R096 Ref document number: 502006012507 Country of ref document: DE Effective date: 20130418 |
|
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed |
Effective date: 20131121 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R097 Ref document number: 502006012507 Country of ref document: DE Effective date: 20131121 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 10 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 11 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: IT Payment date: 20161021 Year of fee payment: 11 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 12 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: PLFP Year of fee payment: 13 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: IT Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20171010 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 20191029 Year of fee payment: 14 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 20201027 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 20201228 Year of fee payment: 15 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 20201010 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20201010 |
|
REG | Reference to a national code |
Ref country code: DE Ref legal event code: R119 Ref document number: 502006012507 Country of ref document: DE |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20220503 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 20211031 |