INDUSTRIAL TRUCK COMPRISING A DEVICE FOR REDUCING VIBRATIONS

Abstract

Industrial truck, in particular a tri-lateral sideloader, comprising

a chassis (6),
a mast (8) arranged on the chassis (6),
a cab (12),
a support structure (9) supporting the cab (12), which can be moved up and down on the mast (8) together with the cab (12) and has at least one cantilever arrangement (24; 124) projecting from the mast (8), which arrangement extends underneath the cab (12) and supports a load-carrying assembly (36) arranged in front of the cab (12),
and a device for reducing vibrations having vibration components transverse to the main direction of travel (G) of the industrial truck, which device allows vibration-reducing movements of the load-carrying assembly (36) relative to the mast (8),
characterised in that
the cantilever arrangement (24; 124) has a division, having a first cantilever portion (50a; 150a), which is coupled to the mast (8) and guided thereon in a height-adjustable manner, as a first part, and having a second cantilever portion (50b; 150b), which supports the load-carrying assembly (36) and is connected to the first cantilever portion (50a; 150a), as the other part, such that, together with the load-carrying assembly (36), it can perform vibration-reducing movements relative to said first cantilever portion, in particular having movement components transverse to the main direction of travel (G) of the industrial truck.

Claims

1. An industrial truck, comprising: a chassis, a mast arranged on the chassis, a cab, a support structure that supports the cab and is configured to be moved up and down on the mast together with the cab and has at least one cantilever arrangement projecting from the mast, which arrangement extends underneath the cab and supports a load-carrying assembly arranged in front of the cab, and a device for reducing vibrations, having vibration components transverse to the main direction of travel of the industrial truck, which device allows for vibration-reducing movements of the load-carrying assembly-relative to the mast, wherein the cantilever arrangement has a division, having a first cantilever portion, which is coupled to the mast and guided thereon in a height-adjustable manner, as a first part, and having a second cantilever portion, which supports the load-carrying assembly is connected to the first cantilever portion, as a second part, such that, together with the load-carrying assembly, it is configured to perform vibration-reducing movements relative to said first cantilever portion.

2. The industrial truck according to claim 1, wherein the first cantilever portion is guided on the mast in a height-adjustable manner so as not to have a horizontal degree of movement freedom, relative to said mast, which is transverse to the main direction of travel of the industrial truck.

3. The industrial truck according to claim 1, wherein the cab is supported on the first cantilever portion and is substantially rigidly connected thereto such that the cab does not directly participate in vibration-reducing movements of the second cantilever portion.

4. The industrial truck according to claim 1, characterised in that wherein the cab is supported on the second cantilever portion such that the cab, together with the second cantilever portion, is configured to perform vibration-reducing movements relative to the first cantilever portion.

5. The industrial truck according to claim 1, wherein the load-carrying assembly comprises a lateral push frame connected to the second cantilever portion for combined movement therewith, a lateral push device which is mounted on the lateral push frame so as to be laterally movable thereon, transversely to the main direction of travel of the industrial truck, and a load-carrying apparatus arranged on the lateral push device which apparatus, together with the lateral push device, is laterally movable transversely to the main direction of travel of the industrial truck by means of a controllable lateral push drive device.

6. The industrial truck according to claim 1, wherein the cantilever arrangement is at least in portions and approximately horizontally such that at least a large part of the length of the first cantilever portion extends underneath the second cantilever portion, supporting it from below, the second cantilever portion being movably mounted on the first cantilever portion by means of a bearing arrangement.

7. The industrial truck according to claim 1, wherein the division of the cantilever arrangement is designed such that the second cantilever portion is arranged in front of the first cantilever portion such that the dividing line between the first cantilever portion and the second cantilever portion extends from above to below, the second cantilever portion being movably mounted on the first cantilever portion by means of a bearing arrangement which is configured to absorb tensile forces as well as compressive forces and shear forces between the two cantilever portions.

8. The industrial truck according to claim 1, wherein the second cantilever portion is coupled to the first load-carrying portion by at least one of a passive damping system or an active damping system which influences the movement of the second cantilever portion relative to the first cantilever portion.

9. The industrial truck according to claim 8, wherein the damping system comprises a friction-damping arrangement.

10. The industrial truck according to claim 9, wherein the friction-damping arrangement comprises at least one of a hydraulic friction-damping cylinder, a pneumatic friction-damping cylinder, or an electromagnetic friction-damping unit.

11. The industrial truck according to claim 8, wherein the damping system comprises a spring arrangement.

12. The industrial truck according to claim 8, wherein the damping system comprises at least one active component, the active component of the damping system acting between the second cantilever portion and the first cantilever portion in order to apply pressure to the second cantilever portion so as to reduce vibrations.

13. The industrial truck according to claim 1, wherein the device for reducing vibrations is selectively activatable and deactivatable.

14. The industrial truck according to claim 13, wherein the device for reducing vibrations is automatically activatable and deactivatable depending on the operating state of the industrial truck in each case.

15. The industrial truck according to claim 1, wherein said industrial truck is designed as a sideloader, the load-carrying assembly of which comprises a load-carrying fork, which has load-carrying arms, as the load-carrying element, which arms are positioned or are configured to be oriented transversely to the straightforward direction of travel of the industrial truck, the device for reducing vibrations being controllable depending on at least one of: the orientation of the load-carrying arms, the lifted vertical position of the load-carrying arms, and/or on or where the industrial truck has stopped and the surroundings thereof.

Description

[0036] Embodiments of the invention are described below with reference to the figures.

[0037] FIG. 1 is a side view of an embodiment of an industrial truck according to the invention, which is designed as a tri-lateral high-bay stacker.

[0038] FIG. 2 is a side view of the support structure arranged on the mast of the industrial truck according to FIG. 1 in a height-adjustable manner, comprising a cantilever arrangement for supporting a cab and a lateral push frame fixed to the front thereof.

[0039] FIG. 3 is a side view of an alternative support structure to be arranged on the mast of an industrial truck of the design shown in FIG. 1 in a height-adjustable manner, comprising a cantilever arrangement for supporting a cab and a lateral push frame of another embodiment of the invention fixed to the front thereof.

[0040] FIG. 1 is a side view of an embodiment of an industrial truck 1 according to the invention, in particular a high-bay stacker which is designed as a tri-lateral stacker.

[0041] The industrial truck comprises a chassis 6 supported via wheels 2 on the ground 4 and a mast 8 vertically fastened to the chassis 6. The mast 8 is constructed of multiple parts so as to be telescopically extendable, as can be seen in FIG. 1 by the extended position indicated by dashed lines. At the furthest extendable telescopic stage 10 of the mast 8, a support structure 9 in the form of a cab carrier is attached such that it can move vertically. The support structure 9 has a cantilever arrangement 24 in the form of a boom, which projects forwards from the mast 8 in the main direction of travel G of the industrial truck and braces the underneath of a platform 11 of a cab 12 and supports a lateral push frame 34 at its projecting end.

[0042] The cab 12 is designed as a lifting driver's cabin, which has a frame comprising the cab platform 11 as the cabin floor, a back wall, side walls and a driver overhead guard 22. At the front of the cab 12, the lateral push frame 34 is fixed to the cantilever arrangement 24.

[0043] The lateral push frame 34 is part of a load-carrying assembly 36, which is known per se and which also comprises a lateral pusher 38 constructed as a pivoting pusher 38 that is arranged on the lateral push frame 34 so as to be laterally movable, transversely to the straightforward direction of travel G of the industrial track, which lateral pusher comprises an additional mast 40 arranged on the front thereof, on which additional mast a load-carrying fork 42 having a fork-carrying arrangement is vertically movable in the form of a load-carrying element. The additional mast 40 can be pivoted together with the load-carrying fork 42 about the vertical axis 44 between the position shown in FIG. 1, in which the load-carrying fork 42 and its load-carrying arms 43 are oriented laterally (transverse orientation to the left in relation to the straightforward direction of travel G), and a position in which they are oriented in an opposing lateral position (transverse orientation to the right) of the load-carrying arms 43.

[0044] The special feature of the industrial truck according to the invention is a device for reducing vibrations, which is designed in particular to reduce vibrations having horizontal deflection components transverse to the main direction of travel G of the industrial truck. For this purpose, in the embodiment shown, the cantilever arrangement 24 is divided into a first cantilever portion 50a and into a second cantilever portion 50b (c.f. in particular FIG. 2), the first cantilever portion 50a being an integral part of the support structure 9 such that it can be vertically moved together with the support structure 9 on the mast 8 but does not have a degree of horizontal movement freedom relative to the mast 8, transversely to the main direction of travel G of the industrial truck.

[0045] However, the second cantilever portion 50b is movably arranged on the first cantilever portion 50a by means of a bearing arrangement 52, which is only indicated schematically in FIG. 1 and FIG. 2, such that the second cantilever portion 50b, along with the load-carrying assembly 36 fastened thereto, can perform vibration-compensating movements, i.e. vibration-reducing movements, relative to the first cantilever portion 50a and therefore relative to the mast 8.

[0046] The bearing arrangement 52 can, for example, be designed as a sliding bearing and/or as a roller bearing, etc. and, as part of the device for reducing vibrations, forms an interface between the cantilever portions 50a and 50b that allows for vibration-reducing movements of the second cantilever portion 50b, the load-carrying assembly 36 placed thereon and a payload that may be supported thereon relative to the first cantilever portion 50a having horizontal movement components transverse to the main direction of travel (straightforward direction of travel) G of the industrial truck.

[0047] In the embodiment according to FIG. 1 and FIG. 2, the cantilever arrangement 24 is divided approximately horizontally and in regions into the first cantilever portion 50a and the second cantilever portion 50b, such that the second cantilever portion 50b extends above the first cantilever portion 50a and is supported, resting on the first cantilever portion 50a, by means of the bearing arrangement 52. The second cantilever portion 50b can act as a support for the cab platform 11 or even form the cab platform.

[0048] In the embodiment according to FIG. 3, the cantilever arrangement 124 is divided approximately vertically into the first cantilever portion 150a and the second cantilever portion 150b, such that the second cantilever portion 150b is located in front of the first cantilever portion 150a, a bearing arrangement 152 being provided as an interface between the cantilever portions 150a and 150b, and being capable of absorbing tensile forces as well as compressive forces and shear forces between the two cantilever portions 150a, 150b. In the embodiment according to FIG. 3 in particular, a corresponding cab can be coupled in a simple manner to the first cantilever portion 150a such that the cab does not have to participate in vibration-compensating movements of the second cantilever portion 150b. Conversely, the cab can be coupled to the second cantilever portion 150b such that it only has to participate in the reduced vibration movements of said portion.

[0049] In an embodiment configured accordingly, having a “horizontally” divided cantilever arrangement 24, direct coupling of the cab to the first cantilever portion 50a but not to the second cantilever portion 50b and vice versa is, however, not ruled out.

[0050] A vibration-damping system is shown schematically by 54 and 154 in the drawings. The vibration-damping system 54 and 154 can be designed so as to be passive, active or semi-active and, for example, can comprise a friction-damping arrangement, which has a braking effect on the movement of the second cantilever portion 50b and 150b relative to the first cantilever portion 50a and 150a, respectively, in order to convert kinetic energy into another form of energy, in particular heat, such that vibration damping of vibrations of the industrial truck, in particular of the mast 8, takes place. Such a friction-damping arrangement can, for example, comprise friction surfaces that are provided with friction linings and rub against one another. A hydraulic cylinder comprising, for example, cylinder chambers short-circuited by means of a throttle point and optionally a pneumatic or hydropneumatic spring-type accumulator connected thereto, can also be an element of the damping system 54 and 154. Furthermore, the damping system can comprise a spring arrangement, for example a mechanical spring arrangement, which counteracts a deflection of the second cantilever portion 50b and 150b relative to the first cantilever portion 50a and 150a, respectively, with a resilient reset tendency.

[0051] It should be pointed out that, according to variants of the damping system 54 and 154, the rigidity of spring arrangements of the damping system 54 and 154 and/or the frictional effect of friction-damping arrangements can be controllable depending on certain operating parameters or operating conditions of the industrial truck, in order to modulate the vibration-damping effect as required.

[0052] One example of an application: while the industrial truck is travelling in a narrow aisle of a high-bay warehouse, the device for reducing vibrations would, for example, be activated, a friction-damping arrangement of the damping system providing a frictional effect adapted to the current situation. If, when the industrial truck is travelling over uneven ground, transverse acceleration occurs at the mast 8 and therefore at the first cantilever portion 50a and 150a, the transverse acceleration is transferred to the second cantilever portion 50b and 150b, respectively, via the bearing arrangement 52 and 152, respectively, the friction-damping arrangement and a spring arrangement of the damping system 54 and 154, respectively, interacting therewith. If the inertial force of the relevant “decoupled or soft-coupled” masses exceeds the value of the adjusted frictional force and the spring force acting in parallel, a relative movement occurs between the second cantilever portion 50b and 150b and the first cantilever portion 50a and 150a, respectively. This relative movement backwards and forwards relative to the target rest position reduces the overall vibration amplitude of the mast 8 and kinetic energy is primarily converted into heat in the friction-damping arrangement.

[0053] The damping system 54 and 154 can have at least one actuator in the form of an active component in addition to or alternatively to passive components. Such an actuator can, for example, be formed by a controllable hydraulic or pneumatic cylinder or a controllable electric motor, and acts between the second cantilever portion 50b and 150b and the first cantilever portion 50a and 150a in order to force the cantilever portions 50a and 150a, and 50b and 150b, respectively, tendentially to a target zero position under deflection relative to one another.

[0054] A control device is provided in such an active system in order to control the active components. Furthermore, sensors can be provided which detect the vibration amplitudes of the mast or components arranged thereon in a height-adjustable manner, the control device being capable of processing data from said sensors in order to control the active components in terms of optimised vibration reduction. In this sense, sensors can also be provided which detect the movement of the second cantilever portion 50b and 150b relative to the first cantilever portion 50a and 150a, respectively.