Industrial truck, especially pallet truck

Abstract

Industrial truck (1), in particular pallet truck, with an electrical energy supply unit, in particular a battery, and an electric drive system, wherein an emergency stop switch is provided which can be actuated by means of an actuating element, in particular a push button, wherein the actuating element (20) is removable from the emergency stop switch, wherein the actuating element (20) has the function of a key for switching the emergency stop switch on and off, characterized in that the actuating element (20) in the state removed from the emergency stop switch has at least one additional function designed as an on-board tool of the industrial truck for the operation of the industrial truck.

Description

[0001] The invention relates to an industrial truck, in particular a pallet truck, with an electrical energy supply unit, in particular a battery, and an electric drive system, wherein an emergency stop switch is provided which can be actuated by means of an actuating element, in particular a push button, wherein the actuating element is removable from the emergency stop switch, wherein the actuating element has the function of a key for switching the emergency stop switch on and off.

[0002] For industrial trucks designed as pallet trucks with an electric drive system, particularly a battery-electric drive system, an emergency stop switch is provided for safety reasons. This switch can be used to immediately disconnect the electrical connection between the battery and the electrical and electronic drive units of the drive system, for example, an electric traction motor and an electric motor driving a hydraulic pump. The emergency stop switch is usually actuated with an actuating element in the form of a push button, so that by striking or pressing the push button, the emergency stop switch can be activated and the electrical connection can be severed.

[0003] An emergency stop switch for an industrial truck with an actuating element designed as a push-button is known from EP 0 863 522 B1. The emergency stop switch comprises a push-button located on a plug part of the battery connector. Upon actuation of the push-button, the connection of a contact pin of the plug part to a motor connection cable is interrupted.

[0004] Such an emergency stop switch can further function as a key switch for switching the industrial truck on and off. By inserting a key into a cylinder lock located on the actuating button and turning the key, the emergency stop switch can be actuated between an off position and an on position. Such an emergency stop switch is known from US Pat. No. 5,444,199 A.

[0005] From DE 100 08 104 C1 an emergency stop switch designed as a key switch for an industrial truck is known, in which the push button of the emergency stop switch has the function of the key for switching the emergency stop switch on or off and can be connected to a plunger of the emergency stop switch or can be removed from the plunger of the emergency stop switch.

[0006] DE 100 55 306 A1 discloses an industrial truck in which a receptacle for an emergency stop switch is formed in a cover of a battery compartment

[0007] The present invention is based on the object of providing an industrial truck of the type mentioned at the outset which is simplified in terms of operation.

[0008] This object is achieved according to the invention in that the actuating element, in the state removed from the emergency stop switch, has at least one additional function designed as an on-board tool for operating the industrial truck. According to the invention, the actuating element can be detached from the emergency stop switch and is therefore removable, and in the detached state has at least one additional function for operating the industrial truck. This allows the actuating element to function as a key with which the emergency stop switch can be switched on and off, and when the actuating element is detached, the actuating element can continue to be used as an on-board tool. This multiple use of the actuating element makes operation of the industrial truck easier.

[0009] According to a preferred embodiment of the invention, the emergency stop switch functions as a key switch which can be actuated between an on position and an off position, wherein the actuating element can be removed from the emergency stop switch when the emergency stop switch is in the off position. This provides a simple way of ensuring safe operation of the industrial truck, since when the actuating element is used as on-board tool, the emergency stop switch is in the off position when removed from the emergency stop switch. In the case of an emergency stop switch which also functions as a key switch for turning the vehicle on or off,If the industrial truck has a locking mechanism that allows the emergency stop switch to be switched off, an anti-theft device can still be created easily by removing the operating element when the emergency stop switch is in the off position. This is because the emergency stop switch cannot be switched into the on position when the operating element is removed, and the industrial truck is therefore not functional, particularly if the industrial truck is equipped with a parking brake that is applied to the braking position when the emergency stop switch is in the off position. For an industrial truck that is used and operated outside of warehouses and production facilities, for example on streets and squares within cities, an anti-theft device can be created easily in this way.

[0010] Particular advantages can be achieved if the industrial truck has a storage container that can be closed by means of a lid, wherein the additional function is formed as an operating element of a locking lock arranged on the lid. The operating element thus has the additional function of a key for the locking lock of the storage container when removed from the emergency stop switch. The lid of a storage container, which may contain, for example, a battery charger, can be opened and locked with the detached operating element of the emergency stop switch by operating the locking lock using the operating element in a simple manner and without an additional operating element. This results in simple operation of the industrial truck due to the multiple use of the detached operating element of the emergency stop switch as an on-board tool.

[0011] If the actuating element can only be attached to or removed from the locking lock when the locking lock is in the locked position, particularly when the lid is closed, this also ensures that the lid of the storage container is locked when the actuating element is removed, thus ensuring that the storage container remains locked during operation of the industrial truck when the emergency stop switch is activated using the actuating element. Furthermore, this also makes it easy to secure the contents of the storage container against theft when the actuating element is removed.

[0012] Particular advantages arise if, according to a preferred embodiment of the invention, the industrial truck is provided with a braking device, in particular a spring-loaded braking device, arranged on a drive wheel, wherein the additional function is designed as an actuating tool, in particular a socket wrench, for applying and securing the braking device in a release position. The removed actuating element of the emergency stop switch can thus continue to be used in a simple manner as an on-board tool and actuating tool to apply a braking device designed as a spring-loaded brake to the release position and to secure it in the release position. This makes it easy to apply the spring-loaded brake to the release position in the event of a discharged battery or a defect in the industrial truck, in order to enable manual operation of the pallet truck.

[0013] A simple and secure attachment of the operating element to the emergency stop switch is achieved if, according to one embodiment of the invention, the actuating element can be connected to the emergency stop switch by a rotary movement in an actuating direction, in particular a rotation of 90°, and a translatory movement in an actuating direction, in particular by pulling. Furthermore, if the emergency stop switch is designed with the function of a key switch that can be actuated by pulling from an off position to an on position, the emergency stop switch can be actuated and actuated into the on position at the same time as the actuating element is connected to the emergency stop switch, for example an actuating plunger of the emergency stop switch, and the industrial truck can be switched on.

[0014] If the actuating element can be separated from the emergency stop switch by translatory movement in the opposite actuating direction, in particular pressing, and rotary movement in the opposite actuating direction, in particular an opposite rotation by 90°, it is achieved in a simple manner that the operating element can only be withdrawn from the emergency stop switch in the off position of the emergency stop switch having the function of a key switch, wherein by pressing on the actuating element to release the actuating element from the emergency stop switch, for example an actuating plunger of the emergency stop switch, the emergency stop switch is simultaneously actuated into the off position.

[0015] According to a preferred development of the invention, a spring device is arranged within the actuating element, by means of which the actuating element can be locked to the emergency stop switch and / or to the locking lock and / or to the braking device. With a spring device arranged and integrated in the actuating element, locking and arresting of the actuating element to the emergency stop switch can be achieved in a simple manner with just one spring device. When using the actuating element removed from the emergency stop switch as an on-board tool, locking of the actuating element to the locking lock or to the braking device can be achieved.

[0016] Further advantages and details of the invention are explained in more detail with reference to the embodiment shown in the schematic figures. Fig. 1 a lift truck according to the invention in a perspective view, Fig. 2 an emergency stop switch with attached actuating element, Fig. 3 and Fig. 4 a storage container with an operating element attached to the lid and Fig. 5 a parking brake with the actuating element as the actuating tool.

[0017] In the Fig. 1 shows an industrial truck according to the invention, for example, a tiller-guided lift truck 1 designed as a low-lift truck, comprising a drive part 2 and a load section 3 that is vertically movable relative to the drive part 2. The drive part 2 comprises a bow-shaped frame section 4, within which a drive wheel 5 is arranged so as to be steerable about a vertical pivot axis. The lift truck 1 is steered by means of a tiller 6 connected to the drive wheel 5 and arranged so as to be pivotable about a horizontal pivot axis. The drive wheel 5 is designed as a pneumatic tire.

[0018] The load section 3 includes two load arms 7a, 7b, with the load section 3 being supported on a track by means of load rollers 8a, 8b arranged at the ends of the load arms 7a, 7b. Loads such as pallets, wire mesh crates, or small parts containers can be picked up, lifted, and transported with the load arms 7a, 7b.

[0019] A vertical frame section 9 is arranged between the drive part 2 and the load part 3. The frame section 9 is designed as a bracket formed by vertically arranged bracket sections 9a, 9b, spaced laterally in the transverse direction of the vehicle, and a horizontal bracket section 9c connecting the bracket sections 9a, 9b. The bracket is bent forward in the vertically upper region toward the drive part 2.

[0020] Within the space of the vertical frame section 9 spanned by the bracket sections 9a, 9b and 9c, a battery holder is arranged, which serves to hold a battery 10 supplying the electric drive system of the lifting truck 1. The battery 10 serves, for example, to supply a drive motor of the drive wheel 5 designed as a wheel hub motor and a Fig. 5 for raising and lowering the load part 3 relative to the drive part 2. The lifting device 11 is formed, for example, by an electric threaded spindle drive.

[0021] The load part 3 is arranged on the bow-shaped frame section 4 of the drive part 2 by means of a lever arrangement formed by articulated levers 12 so as to be movable in the vertical direction.

[0022] The load rollers 8a, 8b arranged on the load arms 7a, 7b are rotatably mounted in load roller supports (not shown) which are pivotally arranged on the load arms 7a, 7b. The load roller supports are each connected to a Fig. 5 is operatively connected to the corresponding articulated lever 12, whereby a lifting movement of the load part 3 relative to the drive part 2 is converted by means of the articulated lever 12 and the rods 13 into a vertical movement of the load rollers 8a, 8b, thus allowing the load part 3 to be raised and lowered relative to the drive part 2. The rods 13 can be designed as push rods or pull rods arranged within the load arms 7a, 7b.

[0023] A storage container 15 is arranged above the battery receptacle for the battery 10, which is also arranged and accommodated within the space of the frame section 9 defined by the bracket sections 9a, 9b, and 9c. The storage container 15 can completely fill the installation space in the transverse direction between the vertical bracket sections 9a, 9b, thereby achieving a large storage volume of the storage container 15.

[0024] The storage container 15 faces the load part 3 and can be closed with a lid 17 that can be folded about a horizontal pivot axis 16.

[0025] The lifting device 11 is arranged within a cover 18, on the top of which an emergency stop switch is arranged, which can be actuated by means of an actuating element 20 designed as a push button.

[0026] The bow-shaped frame section 4 of the drive part 2 and the load part 3 formed by the load arms 7a, 7b and the vertical bow section 9 are formed in the lifting truck 1 according to the invention from one-piece hollow profiles, for example, tubular profiles, with a closed cross-section, whereby the lifting truck 1 has a low dead weight while being highly stable and strong. This design of the drive part 2 and the load part 3 in conjunction with the pneumatic drive wheel 5 makes the lifting truck 1 according to the invention particularly suitable for applications outside of warehouses and production facilities with uneven road surfaces, for example, on streets and squares within cities.

[0027] In the Fig. 2 shows an enlarged view of the cover 18 with the actuating element 20 of the emergency stop switch (not shown in detail). The emergency stop switch additionally functions as a key switch, whereby the emergency stop switch can be actuated by pulling the actuating element 20 into an on position E and by pressing the actuating element 20 into an off position A. By pressing or striking the actuating element 20, the emergency stop switch can be actuated during operation of the lift truck 1 to emergency shut down the lift truck 1 in order to interrupt the electrical connection between the battery and the drive motor and the lifting device.

[0028] According to the invention, the actuating element 20 is removable from the emergency stop switch and, in the state removed from the emergency stop switch, has at least one additional function for operating the industrial truck.

[0029] In the in the Fig. 2, the actuating element 20 is attached to the emergency stop switch and the emergency stop switch is in the on position E. Starting from the Fig. In the on position E shown in Figure 2, the actuating element 20 can be withdrawn from the emergency stop switch by pressing and then turning it 90° counterclockwise, whereby the pressing when separating the actuating element 20 from the emergency stop switch simultaneously actuates the emergency stop switch in the off position A.

[0030] In the off position A of the emergency stop switch, the actuating element 20 can be plugged onto the emergency stop switch, connected to the emergency stop switch by turning it 90° clockwise and then pulling it, whereby at the same time, by pulling while the actuating element 20 is connected to the emergency stop switch, the emergency stop switch is actuated into the on position E. The connection of the emergency stop switch to the actuating element 20 can be made by a corresponding bayonet connection that is formed between the actuating element 20 and an actuating plunger of the emergency stop switch.

[0031] In the Fig. 3 and Fig. 4, the storage container 15 is shown in an enlarged view. The storage container 15 serves, for example, to hold a Fig. 4 shows a charger shown in dashed lines, which is provided with a charging cable and a power cable. A locking lock 25 is arranged on the lid 17 of the storage container 15 to lock the lid 17. This locking lock 25 can be actuated by means of the actuating element 20 removed from the emergency stop switch. When removed from the emergency stop switch, the actuating element 20 of the emergency stop switch thus has the additional function of an operating element and thus a key for the locking lock 25. When the lid 17 is closed and the locking lock 25 is locked, the actuating element 20 can be plugged onto or removed from the locking lock 25. When the actuating element 20 is removed, the lid 17 is closed and locked by means of the locking lock 25. The actuating element 20 can be connected to the locking lock 25 by means of a suitable bayonet connection.

[0032] In addition, the actuating element 20, in the position removed from the emergency stop switch, has the additional function of an actuating tool for a braking device of the lifting truck 1.

[0033] On the drive wheel 5 - as shown in the Fig.5, a braking device 30, designed, for example, as an electromagnetically actuated disc brake, is arranged. The disc brake has a brake disc 32 connected in a rotationally fixed manner to the drive wheel 5 and a brake caliper 33 provided with brake pads. The braking device 30 is designed as a spring-loaded brake, which is acted upon in a braking position by a spring device (not shown in detail) arranged in the brake caliper 33. By means of an actuating magnet, the disc brake can be acted upon in the release position against the force of the spring device.In the event of a discharged battery 10 or a defect in the lifting truck 1, the actuating element 20 of the emergency stop switch can be used as a key and plugged onto the brake calliper 33 in order to actuate the braking device 30 into the release position in a manner not shown in detail and to secure it in the release position, thereby enabling manual operation of the lifting truck 1 without the braking device.

[0034] With the actuating element 20 according to the invention, which can be removed from the emergency stop switch in the off position A and can be used as an on-board tool, for example as an operating element for the locking lock 25 of the lid 17 and thus as a key for opening the lid 17 of the storage container 15, as well as an actuating tool for releasing the braking device 30, additional functions can be achieved and additional devices of the lifting truck 1 can be actuated and operated in a simple manner and with little construction effort. Furthermore, a high level of operational reliability of the lifting truck 1 results, since the actuating element 20 can be removed from the emergency stop switch only in the off position A of the emergency stop switch and can be used to actuate the locking lock 25 or to release the braking device 30.Furthermore, the contents of the storage container 15 and the lift truck 1 itself are easily secured against theft, since when the actuating element 20 is removed, the emergency stop switch is in the off position A and the lid 17 of the storage container 15 is locked by means of the locking lock 25. This results in particular advantages when the lift truck 1 according to the invention is used within cities, since the operator can switch off the lift truck 1 and secure it against theft by simply removing the actuating element 20.

Claims

[1] Industrial truck (1), in particular a pallet truck, with an electrical energy supply unit, in particular a battery, and an electric drive system, wherein an emergency stop switch is provided which can be actuated by means of an actuating element, in particular a push button, wherein the actuating element (20) is removable from the emergency stop switch, wherein the actuating element (20) has the function of a key for switching the emergency stop switch on and off, characterized by that the actuating element (20) in the state removed from the emergency stop switch has at least one additional function designed as an on-board tool of the industrial truck for operating the industrial truck. [2] Industrial truck (1) according to claim 1, characterized bythat the emergency stop switch has the function of a key switch which can be actuated between an on position (E) and an off position (A), wherein the actuating element (20) is removable from the emergency stop switch in an off position (A) of the emergency stop switch. [3] Industrial truck (1) according to claim 1 or 2, characterized by that the industrial truck (1) has a storage container (15) which can be closed by means of a lid (17), wherein the additional function is formed as an operating element of a locking lock (25) arranged on the lid (17). [4] Industrial truck (1) according to claim 3, characterized by that the actuating element (20) can be plugged onto the locking lock (25) and removed from the locking lock (25) in the locked position of the locking lock (25), in particular when the cover (17) is closed. [5] Industrial truck (1) according to one of claims 1 to 4, characterized byin that the industrial truck (1) is provided with a braking device (30), in particular a spring-loaded braking device, arranged on a drive wheel (5), wherein the additional function is designed as an actuating tool, in particular a socket wrench, for applying and securing the braking device (30) in a release position. [6] Industrial truck (1) according to one of claims 1 to 5, characterized by that the actuating element (20) can be connected to the emergency stop switch by rotational movement in an actuating direction, in particular a rotation of 90°, and translational movement in an actuating direction, in particular pulling. [7] Industrial truck (1) according to claim 6, characterized bythat the actuating element (20) can be separated from the emergency stop switch by translatory movement in the opposite actuating direction, in particular pressing, and rotary movement in the opposite actuating direction, in particular an opposite rotation by 90°. [8] Industrial truck (1) according to one of claims 1 to 7, characterized in that a spring device is arranged within the actuating element (20), by means of which spring device the actuating element (20) can be locked to the emergency stop switch and / or to the locking lock (25) and / or to the braking device (30).

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