TRACKED DRIVE FOR STOCK VEHICLE

Abstract

A storage vehicle movable along a stationary guide rail (40) equipped with engagement elements (43), comprising a chassis (50) and a drive unit (20) connected to the chassis (50), which drive unit (20) includes: a drive wheel (21) coupled to a drive motor (60), which has circumferential engagement elements, one or two continuous drive belts (25) equipped with engagement elements, a steering roller arrangement (22, 24, 24a) for guiding the endless drive belt (25), which is designed such that the endless drive belt (25) can be brought into engagement with both the drive wheel (21) and the engagement elements (43) of the stationary guide rail (40) for driving the storage vehicle.

Description

Field of invention

[0001] The invention relates to a drive for vehicles used in warehouses, such as storage and retrieval machines for storing and retrieving items in / from rack storage facilities. Background of the invention

[0002] These types of storage and retrieval machines (SRMs) are used, for example, to load and unload goods from a high-bay warehouse. The SRM travels to the respective storage locations within the warehouse and retrieves or loads the required goods. The performance, i.e., the throughput of such a warehouse, depends critically on the speed and, in particular, the maximum possible acceleration of the SRMs or other storage vehicles. This places high demands on the drive technology of the storage vehicles, especially for vehicles with high tare weight or high payloads.

[0003] In the field of drive technology for vehicles in storage, two different drive variants are predominantly pursued: In a friction drive, the vehicle's own mass generates the contact force between the drive wheel and the road surface. This contact force, through friction between the drive wheel and the road surface, generates a forward force from the drive wheel to the road surface, thus accelerating the vehicle. The magnitude of the acceleration or deceleration therefore depends on the coefficient of friction between the drive wheel and the road surface. Due to the frictional connection between the drive wheel and the road surface (similar to a motor vehicle on the road), only relatively small torques can be transmitted, resulting in comparatively low accelerations and decelerations.

[0004] In a rack and pinion drive, a rack is installed along the entire length of the vehicle's travel path. A drive gear (pinion) engaging with the rack, which is connected to the vehicle's chassis, converts the rotational motion of the driven gear into a translational motion. Rack and pinion drives can transmit high torques, thus enabling high acceleration and deceleration. However, disadvantages include high maintenance requirements (lubrication), significant noise generation, and comparatively high installation costs.

[0005] EP 3 594 171 A1 describes a transport device, in particular a storage and retrieval machine, with a travel path, a carriage which is movable along the travel path and at least one stationary belt which is arranged along the carriage, rests against a support surface and is fixed at a first end and at a second end of the travel path relative to the travel path, wherein the carriage has a drive device which engages with the belt.

[0006] CN 106217410 B describes a belt which is engaged with a linearly arranged engagement element and a toothed clamping plate, but not to transmit a driving motion, but to clamp the toothed belt and reduce the free belt length with respect to elongation and pretension.

[0007] DE 3813897 A1 describes a work device driven by a traction motor that travels on a guide rail. It has a drive unit equipped with ball joints for a measuring carriage fitted with a measuring device, which always travels the same distance as the work device on a control rail. Several conductor rails are also attached to this control rail. The measuring carriage carries a measuring wheel designed as a gear, half of which is enclosed by a measuring belt designed as a toothed belt. In front of and behind the measuring wheel, deflection pulleys press the toothed belt onto the toothed belt support surface associated with the control rail.

[0008] German patent DE 25 40 252 A1 describes a system for storing palletized flat and rod-shaped articles, allowing for the removal of individual items. Several non-powered, mobile rack sets are arranged directly behind one another on rails, over which a portal-type loading and unloading machine travels. This machine is equipped to mechanically open and close the necessary passage between two sets. It features a loading platform with a horizontally movable lifting beam. Two or more mechanisms are mechanically driven along the beam and load and unload the items, either onto pallets or in large units. Additional mechanisms are provided for the removal of individual items.

[0009] DE 102 16 014 A1 describes a storage and retrieval machine for transporting goods from or into a rack, preferably in a picking system, with a bottom-side drive for longitudinal movement and longitudinal positioning of the storage and retrieval machine at an operating point of the rack at the front or rear of the rack, wherein in addition to the bottom-side drive a second top-side longitudinal drive is provided, which can be selectively activated or continuously operated synchronously with the bottom-side drive.

[0010] AT 507 334 A1 describes a storage and retrieval machine with a chassis designed to support a mast comprising a carriage with guide units. The mast has a drive unit with a drive motor attached to the chassis. A rail is attached to the carriage, and in the installed position, a free section is formed directly above the rail in which the guide units are guided within the interior of the rail. The carriage has downward-facing side walls on opposite sides of the rail, the rail having a polygonal cross-section, and one of the guide units being designed as a roller.

[0011] The present invention is therefore based on the objective of proposing a drive concept for a stock vehicle that enables high acceleration and deceleration values ​​while simultaneously requiring low maintenance and assembly effort for the drive elements. Summary of the invention

[0012] The problem is solved by the storage vehicle described in claim 1, which, according to the invention, is movable along a stationary guide rail provided with engagement elements and comprises a chassis and a drive unit connected to the chassis. The drive unit has a drive wheel coupled to a drive motor with circumferential engagement elements, one or two continuous drive belts provided with engagement elements, and a guide roller assembly for guiding the continuous drive belt. This assembly is designed such that the continuous drive belt can engage with both the drive wheel and the engagement elements of the guide rail to drive the storage vehicle. The engagement elements or teeth of the continuous drive belt engage with the engagement elements of the guide rail over a considerable distance, as do the engagement elements of the drive wheel and those of the continuous drive belt.The driving force is therefore distributed across a large number of pairs of engagement elements.

[0013] The drive according to the invention enables high acceleration and deceleration values ​​in both directions of movement, even with large loads, and thus high performance of the storage vehicle with low maintenance requirements and low noise levels.

[0014] Preferably, the endless drive belt is guided around the drive wheel and the guide roller assembly in an omega geometry such that the engagement elements on the same side of the endless drive belt engage with both the drive wheel and the guide rail equipped with engagement elements. The omega geometry enables a compact design of the drive.

[0015] The guide roller arrangement preferably comprises two guide rail-side deflection rollers and two deflection rollers facing away from the guide rail, wherein one or more of the deflection rollers can be designed as a tensioning roller for tensioning the endless drive belt.

[0016] Furthermore, the drive unit can have pressure elements, preferably pressure rollers, for pressing the endless drive belt against the guide rail provided with engagement elements.

[0017] The endless drive belt can be made of elastic material such as plastic or rubber, preferably polyurethane. The use of an NFC fabric can further reduce noise.

[0018] The storage vehicle preferably has guide rollers to maintain a defined distance between the drive unit and the guide rail.

[0019] The drive unit can have one or more drive motors, which are coupled to the axle of the drive wheel via a belt drive. The belt drive can be configured with a reduction or overdrive ratio by selecting appropriate diameters for the pulleys, thus functioning as a gearbox. This eliminates the need for a separate gearbox flanged to the drive motor, resulting in significant weight savings.

[0020] Alternatively, the drive motor can be arranged separately from the drive unit.

[0021] The chassis of the storage vehicle preferably comprises a chassis body and one or more running wheels.

[0022] The invention further relates to a storage vehicle system comprising a guide rail provided with engagement elements and a storage vehicle according to the invention that can be moved along the guide rail.

[0023] The engagement elements of the guide rail can be formed by toothed belts attached to it. These toothed belts can be made of elastic material, preferably polyurethane. NFC fabric can also be used here to reduce noise. The toothed belts are preferably fixed to the guide rail at certain intervals.

[0024] The invention further relates to bearings which have one or more bearing vehicle systems according to the invention, wherein the guide rails are arranged in the longitudinal and / or transverse direction or also in the vertical direction according to a direction of movement of the respective bearing vehicle. Character description

[0025] The invention is described in detail below with reference to exemplary embodiments and the drawings. The drawings show: Fig. 1 a schematic perspective representation of a first embodiment of the chassis of a bearing vehicle according to the invention without a drive element; Fig. 2 a schematic horizontal sectional view of the drive element of the first embodiment of the bearing vehicle according to the invention; Fig. 3 a schematic perspective representation of the drive element according to Fig. 2; Fig. 4 a schematic detailed representation of the drive element according to Fig. 2; Fig. 5 a schematic horizontal sectional view of the drive element of a second embodiment of the bearing vehicle according to the invention; Fig. 6 a schematic perspective representation of the drive element according to Fig. 5; and Fig. 7 a schematic perspective representation of the drive element of a third embodiment of the bearing vehicle according to the invention. Detailed description of the invention

[0026] The Fig. Figures 1-4 show a first embodiment of the storage vehicle according to the invention. Fig. Figure 1A shows a schematic perspective view of the chassis 50 of an exemplary embodiment of a storage vehicle according to the invention. The storage vehicle can perform any number of functions within a warehouse and can have corresponding superstructures and handling elements, which are not shown here and are independent of the invention. For example, the storage vehicle can be used as a racking vehicle for loading and unloading goods from a high-bay warehouse or as a cross conveyor for connecting various conveying elements such as roller or belt conveyors. The invention relates to the drive system of the storage vehicle, which can fulfill a wide variety of functions.

[0027] On the chassis 50 of the in Fig. In the embodiment shown in Figure 1, wheel carriers are mounted on both sides, each containing wheels 30. These guide the storage vehicle through the rack aisle. However, other wheel arrangements are also possible.

[0028] In Fig. Figure 1 shows the guide rail 40, which is fixed in place in the warehouse building and defines the travel path of the warehouse vehicle. As shown in particular in the detailed illustrations of the Fig. 1B and Fig. As can be seen in 1C, a toothed belt 42 with engagement elements (teeth) 43 is attached to the guide rail 40 (see ). Fig. 4) attached. The toothed belt 42 is preferably made of an elastic material such as a plastic or rubber material, in particular polyurethane, and is fixed to the guide rail 40 at certain intervals, forming a fixed unit with it. This unit is preferably mounted over the entire length of the aisle / track of the bearing and can be attached to the floor by means of a rail foot or the like. Compared to a rack, the toothed belt 42 fixed to a guide rail 40 has the further advantage of significantly reduced assembly effort, since several rack elements mounted one behind the other must be aligned very precisely with each other, which entails high manufacturing costs. This effort is eliminated when using a toothed belt.

[0029] Fig. Figure 2 shows a schematic horizontal section view and Fig. Figure 3 shows a perspective view of the drive unit 20, which accelerates and propels the storage vehicle along the track. In the upper part of the image... Fig. 2 shows part of the chassis carrier 51 and one of the running wheels 30.

[0030] The toothed belt 42 engages the engagement elements (teeth) of an endless drive belt 25, which, in the illustrated embodiment, is guided in an omega geometry around an arrangement of deflection pulleys 22, 24, 24a and a drive wheel or drive pulley 21, which is also provided with engagement elements (teeth). The toothed side of the endless drive belt 25 is inserted into the toothed belt 42. One or more deflection pulleys are movably designed as tensioning pulley(s) 24a for adjusting the tension of the endless drive belt 25.

[0031] The drive wheel 21 is coupled to an electric motor or other suitable drive unit. Due to the omega geometry, the engagement elements of the drive wheel 21 are in engagement with the engagement elements of the endless drive belt 25 over a significant portion of the circumference of the drive wheel 21, thus ensuring good power transmission from the drive wheel 21 to the endless drive belt 25 with low maintenance requirements.

[0032] The drive unit 20 is preferably rigidly connected to the chassis carrier 51 of the vehicle in storage and can be detached from it by dismantling various components. A guide roller 27, which is located particularly in the Fig. 3 and Fig. As shown in Figure 4, the drive unit 20 is held at a constant distance from the chassis support 51, ensuring good engagement of the engagement elements of the endless drive belt 25 with the corresponding engagement elements of the toothed belt 42. Pressure rollers 28 are also provided, which ensure the contact pressure of the endless drive belt 25 on the toothed belt 42 required for power transmission. The power transmission from the endless drive belt 25 to the toothed belt 42 is distributed across a multitude of engagement element pairs, thus reducing the force and therefore the wear on each individual engagement element. This allows noise-reducing materials such as polyurethane and NFC fabric to be used for the drive wheel 21, the endless drive belt 25, and the toothed belt 42. The toothed belt 42 transmits the power to the ground via the guide rail 40 and the ground connection.

[0033] The Fig. 5 and Fig. Figure 6 shows a second embodiment of the drive unit 20 of the storage vehicle according to the invention. The functionality of the second embodiment corresponds essentially to that of the first embodiment, but is characterized by a particularly compact design.

[0034] Fig.Figure 7 shows a third embodiment of the drive unit 20 of the storage vehicle according to the invention, which is based on the second embodiment but differs from it in that two drive motors 60 are directly attached to the drive unit. The drive force is transmitted from the motors 60 to the drive shaft of the drive wheel 21 via belt drives 29. By appropriately selecting the diameters of the belt pulleys, a suitable gear ratio or reduction can be chosen between the drive motors 60 and the drive wheel 21. In this way, the belt drive can simultaneously serve as a gearbox, thus eliminating the need for a heavy and bulky motor gearbox.

[0035] The storage vehicle according to the invention enables high accelerations and decelerations in both directions of movement, even with heavy loads, thereby increasing the performance of the associated warehouse. The storage vehicle can be moved along the aisle of a racking system or used as a transverse conveyor perpendicular to the aisle direction, or for connecting various conveying elements such as roller or belt conveyors. The drive system according to the invention can also be used to drive vertical conveyors.

Claims

[1] A storage vehicle movable along a stationary guide rail (40) equipped with engagement elements (43), comprising a chassis (50) and a drive unit (20) connected to the chassis (50), which drive unit (20) includes: a drive wheel (21) coupled to a drive motor (60), which has circumferential engagement elements, one or two continuous drive belts (25) equipped with engagement elements, a steering roller arrangement (22, 24, 24a) for guiding the endless drive belt (25), which is designed such that the endless drive belt (25) can be brought into engagement with both the drive wheel (21) and the engagement elements (43) of the stationary guide rail (40) for driving the storage vehicle. [2] Storage vehicle according to claim 1, wherein the endless drive belt (25) is guided in an omega geometry around the drive wheel (21) and the steering roller arrangement (22, 24, 24a) such that the engagement elements on the same side of the endless drive belt (25) engage both with the drive wheel (21) and with the guide rail (40) provided with engagement elements (43). [3] Bearing vehicle according to claim 2, wherein the steering roller arrangement (22, 24, 24a) comprises two guide rail-side deflection rollers (22) and two deflection rollers (24, 24a) facing away from the guide rail (40). [4] Bearing vehicle according to claim 3, wherein at least one of the deflection rollers (24a) is designed as a movable tensioning roller for tensioning the endless drive belt (25). [5] Bearing vehicle according to claim 4, comprising pressure elements (28) for pressing the endless drive belt (25) against the guide rail (40) provided with engagement elements (43). [6] Bearing vehicle according to claim 5, wherein the pressure elements (28) are designed as pressure rollers. [7] Bearing vehicle according to one of claims 1-6, comprising one or more guide rollers (27) for maintaining a defined distance between the drive unit (20) and the guide rail (40). [8] Storage vehicle according to one of claims 1-7, wherein the endless drive belt (25) is made of elastic material, preferably polyurethane. [9] Storage vehicle according to one of claims 1-8, wherein the drive unit (20) has at least one drive motor (60) which is coupled to the axle of the drive wheel (21) via a belt drive (29). [10] Bearing vehicle according to claim 9, wherein the belt drive (29) implements an over- or under-reduction of the drive force. [11] Storage vehicle according to one of claims 1-10, wherein the chassis (50) comprises a chassis body (51) and one or more running wheels (30). [12] Storage vehicle system comprising a guide rail (40) provided with engagement elements (43) and a storage vehicle movable along the guide rail (40) according to one of claims 1-11. [13] Bearing vehicle system according to claim 12, wherein the engagement elements (43) are formed by toothed belts (42) applied to the guide rail (40). [14] Bearing vehicle system according to claim 13, wherein the toothed belts (42) are made of elastic material, preferably polyurethane, and are fixed at intervals on the guide rail (40). [15] Bearing comprising one or more bearing vehicle systems according to one of claims 12-14, wherein the guide rails (40) are arranged in the longitudinal and / or transverse direction or also in the vertical direction according to a direction of movement of the respective bearing vehicle.

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