Power supply unit for mobile work machine and mobile work machine

Abstract

In a power supply unit for a mobile work machine (2), which can be inserted as a closed component in a battery compartment (10) in an exchangeable manner, at least one side wall (17) of the power supply unit (12) is provided with a penetration protection plate (15).

Description

[0001] The invention relates to a power supply unit for a mobile work machine and to a mobile work machine. In particular, the invention relates to a power supply unit for a mobile work machine that can be inserted into a battery compartment as a closed component, wherein at least one side wall of the power supply unit is provided with a penetration protection plate. Furthermore, the invention relates to a mobile work machine with an electric drive and a battery compartment for accommodating a power supply unit for supplying the electric drive.

[0002] From DE 43 05 190 A1, a generic energy supply unit for a mobile work machine with the features of the preamble of patent claim 1 is known.

[0003] DE 10 2006 059 324 A1 discloses an industrial truck with a battery block and a side frame opening.

[0004] US 4 174 014 A discloses a shock-absorbing electric motor vehicle.

[0005] DE 10 2011 120 010 A1 discloses a battery for an industrial truck in which an energy-absorbing protective element is arranged at least on an outer side of a battery housing.

[0006] Increasingly, modern batteries with very high energy density are being used as traction batteries in mobile work machines with electric drive and power from a traction battery, instead of the traditional lead batteries. Examples of such traction batteries include lithium-ion batteries, but can also include other battery technologies that offer significantly higher energy densities than conventional lead batteries.

[0007] Another form of energy storage used with high power density is double-layer capacitors.

[0008] If such high-energy-density traction batteries such as lithium-ion batteries are mechanically damaged, their high energy density can lead to fires or gas emissions on a much greater scale than with conventional lead batteries, for example, due to short circuits with rapid energy release. Unlike conventional lead batteries, which only leak liquid electrolyte in the event of an accident, such modern energy storage devices consist to a much greater extent of flammable materials, and their components, such as lithium and the lithium compounds used, are often highly chemically reactive. The release of hazardous gases can also occur.

[0009] Other energy storage devices with high energy density also pose a higher risk of fire in the event of damage, for example due to the energy released in the event of a short circuit or mechanical damage.

[0010] It's also known that fuel cells are used as power supply units in mobile machinery. These, too, can pose hazards due to mechanical damage, for example, if hydrogen is released.

[0011] In passenger cars, it is common practice to install lithium-ion batteries in the protected area of ​​a passenger compartment or in the part of the trunk that still qualifies for this protection. In the event of a typical road traffic accident, the lithium-ion battery is thus protected to at least the same extent as the vehicle occupants, and only minor damage can occur.

[0012] However, with mobile work machines, the problem is that the primary accident types are not typical traffic collisions with energy dissipation in crumple zones. The typical vehicle structure of a mobile work machine, especially an industrial truck, differs significantly from that of a passenger car. A load-bearing frame structure is provided, which is optimized, for example, in the case of a forklift truck as an industrial truck, to carry a counterweight and the lifting mast. The traction battery or power supply unit is then located between the axles in the area below or behind the driver's workplace. Special precautionary measures against collisions are generally not in place.The power supply unit arranged in a battery compartment often takes up the entire width of the vehicle and the battery compartment is separated from the surrounding area between the frame elements only by panels or by an access door provided for battery replacement.

[0013] However, mobile work machines in general often have attachments and working devices that protrude considerably. Of particular importance in forklifts are the load forks with their two fork tines. The forks are made of solid material, making them very stable and rigidly supported longitudinally relative to the load carrier or mast. In addition, a forklift exhibits considerable kinetic energy due to its weight.

[0014] It is also very common for multiple forklifts to be used on a factory site. Therefore, if one forklift collides with the side of a second forklift, forks first, the forks can penetrate deeply into the areas between the frame elements. With conventional lead-acid batteries, this would destroy the traction battery and cause electrolyte leakage, but would rarely cause further damage. However, with electrically powered forklifts equipped with a power supply unit, which could be a high-energy-density battery or a fuel cell unit, the problems generally described above can occur.

[0015] The present invention is therefore based on the object of providing an energy supply unit for an industrial truck and an industrial truck which avoids the above-mentioned disadvantages and in which the risk of damage is reduced in the event of a collision.

[0016] This object is achieved by a power supply unit for a mobile work machine having the features of independent patent claim 1 and by a mobile work machine having the features of independent patent claim 4. Advantageous developments of the invention are specified in the subclaims.

[0017] The object is achieved in that, in a power supply unit for a mobile work machine, which can be inserted as a closed component in a battery compartment in an exchangeable manner, at least one side wall of the power supply unit is provided with a penetration protection plate, wherein the penetration protection plate consists of a multi-layer armor or wherein the penetration protection plate consists of a bulkhead armor or wherein the penetration protection plate consists of an additional weight element.

[0018] A penetration protection plate prevents damage to the power supply unit, particularly in the event of an accident between two work machines, from the attachments, in particular the forks on a forklift truck, for example an industrial truck. The power supply unit can advantageously be designed as a battery with high energy density, for example, but also as a fuel cell unit. By providing the penetration protection plate on the power supply unit itself, a mobile work machine designed for conventional lead batteries can use a battery with high energy density while still achieving increased protection against the accidents described. Any type of flat material that prevents mechanical penetration is suitable as a penetration protection plate.This can be achieved, for example, by distributing the point-like force over a larger area. It is conceivable to use all known technologies used in the military sector for armoring vehicles to achieve protection against penetration due to high point-like forces, such as kinetic energy. Because the power supply unit itself contains the penetration protection plate, improved protection against the hazards described can also be achieved in conventional industrial trucks and mobile work machines without the need for modification. For example, a lithium-ion battery can be manufactured as a traction battery, which offers protection against such collisions and can be used in an industrial truck as a mobile work machine without the need for modification.

[0019] In an advantageous further development, the side wall, which in the inserted state is oriented towards an opening of the battery compartment provided for inserting the power supply unit, is provided with a penetration protection plate.

[0020] In many mobile machines, the battery compartment is arranged so that the replaceable traction battery can be removed from the side. The battery compartment is closed only by a door that is not particularly strong. The proposed design thus ensures that this side also provides protection against damage to the power supply unit, which is installed in the battery compartment instead of the lead-acid battery.

[0021] Penetration protection plates can advantageously be provided on two opposite side walls.

[0022] This provides improved protection for mobile work machines where a battery compartment extends across the entire width of the vehicle. In a counterbalance forklift truck, a typical example of a mobile work machine in the form of an industrial truck, a power supply unit in the battery compartment is protected against damage from the front by the mast and from the rear by the counterweight. Protection on the top and bottom is normally not required. By using a power supply unit that is protected on both ends with respect to the direction of insertion into the battery compartment, the hazards in the event of a lateral collision can be reduced.

[0023] The object is also achieved by a mobile work machine with an electric drive and a battery compartment for accommodating a power supply unit for supplying the electric drive, in which the battery compartment is protected at least in part of its wall surface by penetration protection plates, wherein the penetration protection plate consists of a multi-layer armor or wherein the penetration protection plate consists of a bulkhead armor or wherein the penetration protection plate consists of an additional weight element.

[0024] The previously described advantages also apply here. By installing the penetration protection plate on a vehicle frame or chassis, a point-applied force from a fork penetrating, for example, in the event of a collision, is distributed more widely and diverted. Penetration and damage to the power supply unit can be prevented. The penetration protection plates are preferably installed in areas that are not already protected by components such as the lifting frame or by a counterweight in the case of a counterbalanced forklift truck, for example, a mobile work machine.

[0025] In an advantageous further development, the battery compartment has a lateral opening with respect to a vehicle longitudinal direction for replacing the energy supply unit and a door closing the opening has a penetration protection plate.

[0026] Many mobile machines feature a side-mounted battery compartment for the replaceable traction battery. The battery compartment is closed only by a relatively unstable door. The proposed design also provides advantageous protection from this side against damage to the power supply unit installed in the battery compartment.

[0027] The battery compartment may extend across the entire width of the vehicle and may also have a penetration protection plate on the side opposite the opening for replacing the power supply unit.

[0028] In a counterbalance forklift, a typical example of an industrial truck, the power supply unit in the battery compartment is protected against damage from the front by the mast and from the rear by the counterweight. Protection on the top and bottom is normally not required. By providing protection on both sides of the battery compartment, the power supply unit is protected in all relevant directions.

[0029] The mobile work machine is advantageously an industrial truck, in particular a counterbalance forklift or a tractor.

[0030] Since several industrial trucks are often used on a company premises, and especially on larger factory premises a number of counterbalance forklifts, this offers particular advantages, as in the event of a collision between an industrial truck and a forklift truck, a fork tine has a high potential for causing damage extending far into the interior of the industrial truck.

[0031] A mobile work machine described above may also have a power supply unit as described above.

[0032] The protection provided by penetration protection plates can also be divided between the power supply unit and the mobile work machine.

[0033] According to the invention, the penetration protection plate consists of a multi-layer armor, in particular a composite armor containing plastic layers.

[0034] According to the invention, the penetration protection plate can alternatively consist of bulkhead armor.

[0035] In principle, known technologies of armor plating can be used on vehicles, whereby the focus here is on a strong, point-like force load, which is not caused by a projectile with a relatively low weight, but by attachments and in particular the tip of a fork of an industrial truck or a mobile work machine.

[0036] According to the invention, the penetration protection plate alternatively consists of an additional weight element, in particular a solid metal plate.

[0037] Since batteries with high energy density are considerably lighter as energy storage devices than comparable lead-acid batteries, penetration protection plates can be provided as additional weights, consisting of solid metal plates. In addition to the protective effect, this also allows the traction battery to be approximately the same weight as a comparable lead-acid battery, ensuring the stability and sturdiness of a mobile machine or industrial truck is the same as with a lead-acid battery. Likewise, the stability of a mobile machine or industrial truck can be improved if the penetration protection plate also serves as an additional weight.

[0038] The energy supply unit is particularly advantageous as it is a lithium-ion battery.

[0039] It can be particularly beneficial in reducing the risk of fire and the release of gases.

[0040] The power supply unit may be a fuel cell unit.

[0041] Further advantages and details of the invention are explained in more detail with reference to the exemplary embodiments shown in the schematic figures. Fig. 1 a counterbalance forklift truck as an example of a mobile work machine according to the invention, Fig. 2 an embodiment of a power supply unit according to the invention in a detailed cross-section inserted in a battery compartment, Fig. 3 a battery compartment of the counterbalance forklift truck Fig. 1 in perspective view and Fig. 4 shows a cross-section detail of the battery compartment of the counterbalance forklift truck of the Fig. 1.

[0042] The Fig. Figure 1 shows a counterbalance forklift 1 as an example of a mobile work machine 2, designed as an industrial truck 3. A mast 4 guides a load fork 5 with fork tines 6 that can be adjusted in height. A battery compartment 10 is located between a front axle 7 and a rear axle 8, above which a counterweight 9 is arranged. A driver's workstation 11 is arranged above the battery compartment 10.

[0043] The Fig. 2 shows an embodiment of an energy supply unit 12 according to the invention, which is installed in the battery compartment 10 of the counterbalance forklift truck 1 of the Fig. 1 is inserted. The power supply unit 12, designed as a lithium-ion battery 13, has an additional counterweight element 14, which serves as a penetration protection plate 15 and is designed as a solid metal plate 16. By arranging the penetration protection plate 15 on a side wall 17 of the power supply unit 12, which is oriented towards a vehicle side 18 when the power supply unit 12 is inserted into the battery compartment 10, penetration of, for example, a fork tine 6 into the actual interior of the power supply unit 12 is prevented in the event of a collision.

[0044] Advantageously, the lithium-ion battery 13 has a similar or identical weight to a conventional lead-acid battery due to the additional counterweight elements 14. As a result, the lithium-ion battery 13 can be used as the power supply unit 12 in the counterbalance forklift truck 1 of the Fig. 1 without the need for any special adjustments to ensure stability.

[0045] The Fig. 3 shows a battery compartment 10 of the counterbalance forklift 1 of the Fig. 1 in a perspective view, wherein the counterbalance forklift 1 is modified according to the invention. Corresponding components are shown in the previous figures with the same reference numerals. The battery compartment 10 is arranged in front of the front axle 7, indicated by a fender 19, and is shown open to the front and top. On the inside of one vehicle side wall 18 there is a penetration protection plate 15, which is also designed as a counterweight element 14 in the form of a solid metal plate 16. On the opposite vehicle side 20 there is a door 21 through which a replaceable traction battery or the power supply unit 12 can be inserted into the battery compartment 10. The door 21 also has a penetration protection plate 15 designed as a counterweight element 14 in the form of a solid metal plate 16.Thus, the counterbalance forklift 1 is protected on both sides 18, 20 against the penetration of components from other vehicles, especially forks 6 of other industrial trucks. The mast 4 and the counterweight 9 also provide protection against collisions from the front and rear, respectively.

[0046] The Fig. Figure 4 shows a cross-sectional detail of the battery compartment 10 of the counterbalance forklift truck of Fig. 1. On the inside of the vehicle side wall 18 there is the counterweight element 14 in the form of the solid metal plate 16 as a penetration protection plate 15. A power supply unit 12 is inserted into the battery compartment 10, which in this embodiment does not require its own penetration protection plates.

[0047] It is also possible to combine both and to provide both the power supply unit 12 and the counterbalance forklift 1 with penetration protection plates.

Claims

[1] Energy supply unit for a mobile work machine (2), which can be inserted as a closed component in a battery compartment (10) in an exchangeable manner, wherein at least one side wall (17) of the power supply unit (12) is provided with a penetration protection plate (15), characterized by , that the penetration protection plate (15) consists of a multi-layer armor or that the penetration protection plate (15) consists of a bulkhead armor or that the penetration protection plate (15) consists of an additional weight element (14). [2] Power supply unit according to claim 1, characterized by that the side wall (17), which in the inserted state is oriented towards an opening of the battery compartment (10) provided for inserting the power supply unit (12), is provided with a penetration protection plate (15). [3] Power supply unit according to claim 1 or 2, characterized bythat penetration protection plates (15) are provided on two opposite side walls (17). [4] Mobile work machine with an electric drive and a battery compartment (10) for accommodating a power supply unit (12) for supplying the electric drive, characterized by , that the battery compartment (10) is protected at least in part of its wall surface (18, 20) by penetration protection plates (15), wherein the penetration protection plate (15) consists of a multi-layer armor or wherein the penetration protection plate (15) consists of a bulkhead armor or wherein the penetration protection plate (15) consists of an additional weight element (14). [5] Mobile work machine according to claim 4, characterized byin that the battery compartment (10) has a lateral opening with respect to a vehicle longitudinal direction for exchanging the power supply unit (12) and a door (21) closing the opening has a penetration protection plate (15). [6] Mobile work machine according to claim 5, characterized by , that the battery compartment (10) extends over the entire width of the vehicle and also at the opening for replacing the power supply unit (12) opposite side has a penetration protection plate (15). [7] Mobile work machine according to one of claims 4 to 6, characterized by that the mobile work machine (2) is an industrial truck (3). [8] Mobile work machine according to one of claims 4 to 7 with a power supply unit (12) according to one of claims 1 to 3. [9] Mobile work machine or power supply unit (12) according to one of claims 1 to 8, characterized bythat the multi-layer armor is a composite armor containing plastic layers. [10] Mobile work machine or power supply unit (12) according to one of claims 1 to 9, characterized by that the additional weight element (14) is a solid metal plate (16). [11] Mobile work machine or power supply unit (12) according to one of claims 1 to 10, characterized by that the power supply unit (12) is a lithium-ion battery (13). [12] Mobile work machine or power supply unit (12) according to one of claims 1 to 11, characterized by that the energy supply unit (12) is a fuel cell unit.

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