Load carrier for transporting a load and vehicle with a load carrier

Abstract

The invention relates to a load carrier (LT) for transporting and / or storing a load (L), having a loading surface on which the load (L) can be positioned, and having a device for detecting the weight force (G) of the load (L), wherein the device has at least one pressure-sensitive sensor element (20) which is designed to generate an output signal when subjected to the weight force (G).

Description

Technical area

[0001] The invention relates to a load carrier for transporting and / or storing a load, in which the weight of the load is detected by at least one pressure-sensitive sensor element in the area of the load carrier. Furthermore, the invention relates to a vehicle, in particular a driverless transport vehicle, with at least one load carrier designed according to the invention. State of the art

[0002] From DE 10 2021 210 525 A1, it is known to equip a transport vehicle designed as a driverless vehicle, on whose loading area a load can be transported or conveyed, for example, within a warehouse, with an image-recording camera unit. The camera unit serves to record the outline or geometry of the load on the loading area. By recording the size or geometry of the load, a specific route with a certain minimum distance from other objects can be selected, for example, to avoid the risk of collision with loads arranged on other vehicles, or to park the load, for example, on areas of the warehouse adapted to the geometry of the load.

[0003] Furthermore, it is known from DE 10 2022 201 311 A1 by the applicant to capture a load in the area of a load carrier using an image-recording device. This makes it possible, in particular, to determine the position of the load or the load relative to storage locations in a warehouse. Disclosure of the invention

[0004] The load carrier according to the invention for transporting and / or storing a load with the features of claim 1 has the advantage that it enables simple and precise weight recording of the load arranged in the load carrier, particularly in connection with transport on the loading area of a vehicle. In particular, it is also possible to determine not only the absolute weight, but also the weight distribution of the load on the loading area of the load carrier, in order to be able to carry out appropriate driving interventions (automatically) in the event of critical center of gravity positions of the load carrier on the loading area of the vehicle, or, for example, to give a driver a corresponding indication. In addition, with a sufficiently high resolution or precise recording of the weight distribution, it is possible to draw conclusions about objects located in the load carrier or the load. This information can be used for inventorying, i.e.that it is known where, in what quantity, and what type of load is located in the load carriers. The load carrier is preferably designed to store the load. For example, the load carrier serves to store the load in a warehouse. Alternatively and additionally, the load carrier is designed so that the load carrier is loaded and / or unloaded with the load by a robot and / or a gripper. It is also very easy to determine the presence of the load on the load carrier, which enables a monitoring function for the load or theft protection.

[0005] The invention is based on the idea of detecting the weight of a load arranged on a loading surface of the load carrier using at least one pressure-sensitive sensor element. When subjected to a weight force, this sensor element generates an output or voltage signal that can be evaluated. Such multi-layer pressure-sensitive sensor elements are known per se, for example, in connection with handling robots as protective skin for arms on the handling robots. These can be used to detect any collisions that may occur in order to stop the operation of the handling robot.

[0006] Against the background of the above explanations, a load carrier according to the invention for transporting a load with the features of claim 1 therefore has a loading surface on which the load can be positioned. Furthermore, the load carrier has a device for detecting the weight of the load, wherein the device has at least one pressure-sensitive sensor element which is designed to generate an output signal when subjected to the weight force, and wherein the at least one pressure-sensitive sensor element is arranged in the region of the loading surface of the load carrier such that the load can be positioned in at least indirect contact with the at least one pressure-sensitive sensor element.

[0007] Advantageous further developments of the load carrier according to the invention for transporting a load are set out in the subclaims.

[0008] In a particularly preferred structural embodiment of the at least one pressure-sensitive sensor element, it is provided that this consists of at least three layers connected to one another, a middle layer made of an electrically insulating and elastically deformable material, preferably made of plastic, in particular PVDF, and two electrically conductive layers arranged on opposite sides of the middle layer and covering the middle layer at least in regions, which can be connected to a voltage source, wherein a voltage signal can be generated when subjected to the weight of the load.

[0009] With regard to an advantageous geometry and arrangement of the at least one pressure-sensitive sensor element, which is adapted to the shape of the load, it is provided that this is designed as a rectangular sensor element with several spatially separated or individually evaluable segments, or as a strip-shaped sensor rail or as a sensor plate with several sensor elements, which are preferably arranged at equal distances from one another. In particular, for precise charge detection, it is expedient to provide for a possible fine segmentation of the sensor element, i.e., the highest possible number of individually evaluable segments.

[0010] To prevent the load from slipping on the load carrier, particularly during transport on a vehicle, it is preferably provided that the loading surface of the load carrier or the at least one pressure-sensitive sensor element is provided with an anti-slip coating on the side facing the load. Such an anti-slip coating can be designed, for example, in the form of a one-component polyurethane coating or a two-component epoxy resin coating, optionally glass fiber reinforced for high loads.

[0011] To avoid mechanical damage to the pressure-sensitive sensor element, particularly in the case of hard or sharp elements of the load, it is also advantageous if the loading surface of the load carrier is designed as a loading floor, with the at least one pressure-sensitive sensor element being arranged on the side of the loading floor facing away from the load. Thus, if the loading floor is constructed from a hard wood or a hard plastic, for example, direct impact of the load on the pressure-sensitive sensor element, with potentially occurring damage or pre-damage, can be avoided.

[0012] In a further development of the last proposal, it is particularly preferred that the loading floor is interspersed with force transmission elements which transmit the weight force in the load to the at least one sensor element.

[0013] A further advantageous embodiment of the load carrier provides that a base plate is arranged on the side of the at least one pressure-sensitive sensor element facing away from the loading floor, on which the at least one pressure-sensitive sensor element rests at least indirectly. Spacer elements are arranged between the base plate and the loading floor to protect the at least one pressure-sensitive sensor element from overload. Such spacer elements ensure that, when a certain load or weight of the load is exceeded, the load rests on the spacer elements, thus preventing any further or greater weight from being transferred to the pressure-sensitive sensor element.

[0014] It is also preferred if the load carrier is designed as a cargo box. The advantage of this design is that the cargo boxes can be stacked on top of each other, for example, for transporting the load carriers on a vehicle.

[0015] In order to transmit the weight force detected by the at least one pressure-sensitive sensor element, it is furthermore advantageous if the output or voltage signal can be transmitted to a control device, preferably wirelessly.

[0016] Furthermore, the invention also encompasses a vehicle, in particular a driverless transport vehicle, which is designed to transport at least one load carrier according to the invention as described above and preferably comprises at least one load carrier according to the invention. Furthermore, a control device is provided for at least indirectly influencing the driving operation of the vehicle depending on the output or voltage signals transmitted by the at least one load carrier.

[0017] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawings. Short description of the drawings Fig. 1 shows a simplified representation of a driverless transport vehicle with three load carriers arranged on it, Fig. 2 a schematic representation of a pressure-sensitive, rectangular sensor element formed from several layers, Fig. 3 a section through a charge carrier according to the invention with a charge arranged therein and Fig. 4 a section through the sensor element of the charge carrier of the Fig. 3. Embodiments of the invention

[0018] Identical sensor elements or sensor elements with the same function are provided with the same reference numbers in the figures.

[0019] In the Fig. 1 shows a simplified representation of a vehicle 10 in the form of an automated guided vehicle 12. The vehicle 10 or the transport vehicle 12 serves to transport a load L, for example, within a storage area or warehouse. In particular, the so-called industrial truck is designed to at least partially, preferably completely autonomously, pick up the load L at a pick-up location and deposit or store it at a storage location. In the figures, the load L is shown (in simplified form) as a cuboid.

[0020] The load L can be any load L, for example bulk goods or several loads L arranged in the area of the load carrier LT.

[0021] For autonomous driving, the transport vehicle 12 - as is known per se - has devices for detecting its surroundings and calculating a driving route. Furthermore, the transport vehicle 12 has, for example, a control device designed to control the driving operation of the transport vehicle 12, i.e., acceleration, braking, steering angles, etc. Alternatively, the control device can also be designed to be connected to an external device that regulates or advantageously controls the driving operation not only of the transport vehicle 12, but in particular of several transport vehicles 12. In this case, corresponding commands are transmitted (wirelessly) from the external control device to the control device of the respective transport vehicle 12.

[0022] In the illustrated embodiment, the transport vehicle 12 has an approximately rectangular loading area 14. In the illustrated embodiment, three load carriers LT in the form of storage boxes 16 are stacked one above the other on the loading area 14 of the transport vehicle 12. Each of the storage boxes 16 can contain a load L. The lowest load carrier LT has a loading area 18 and rollers 21.

[0023] In the Fig. 2 shows a flat, pressure-sensitive sensor element 20 which serves to detect the weight force G of the load L located in a storage box 16. The pressure-sensitive sensor element 20 has at least three interconnected layers 21, 22 and 23. The Fig. 2 upper layer 21 comprises three strip-shaped segments 24a, 24b and 24c, which are arranged parallel and at a small distance from each other. Fig. 2 lower layer 23 is in turn divided into several, in the embodiment square segments 26, wherein in the Fig. 2, only two segments 26 are shown or recognizable. The segments 26 are also arranged at a small distance from one another. The two edge layers 21 and 23 are each designed as electrically conductive electrodes and connected to a voltage source (not shown), while the middle layer 22 is made of plastic, in particular PVDF, and is designed to be elastically deformable.

[0024] When a weight force G is applied by the load L to the upper layer 21, the distance between the two outer layers 21 and 23 decreases, thereby generating an output or voltage signal in a known manner, which is fed to an evaluation electronics 28. Because the upper layer 21 and the lower layer 23 are divided into segments, a weight force G of the load L acting there can be recorded for each segment 26, with the sum of the individual weight forces G then corresponding to the (total) weight force G of the load L. Furthermore, the distribution of the weight force G on the segments 26 can be used to draw conclusions about the distribution of the weight force G of the load L on the sensor element 20 and thus also on the loading area 14 of the vehicle 10. The smaller the size of the segments 26 or the greater their number, the greater the resolution orThe more accurately the weight distribution of the weight force G of the load L in a load carrier LT can be recorded or determined. High resolution not only allows for precise center of gravity determination, but also enables load detection.

[0025] The evaluation electronics 28 transmits the output or voltage signals of the load carrier(s) LT, preferably wirelessly, to a control device 29. The control device 29 can either be a component of the vehicle 10 or be designed as a higher-level control device 29 arranged spatially separately from the vehicle 10 and serve to regulate the driving operation of the vehicle 10, in particular in the case of a driverless transport vehicle 12. The control device 29 has, in particular, an algorithm for calculating the weight forces G of the load carriers LT on a vehicle 10 and their weight distribution for determining the center of gravity. In particular, when critical weight distributions are detected, an (automated) intervention in the driving operation can take place, for example a limitation of acceleration or deceleration or steering angles. In the event that the vehicle 10 is controlled by an operator orDrivers can receive appropriate warnings (e.g. visual or acoustic).

[0026] In addition, it is mentioned that instead of a single (rectangular) sensor element 20 in the area of the charge carrier LT, several separate, in particular strip-shaped sensor elements 20 as so-called sensor rails 20, or as described below a sensor plate 33, may also be present.

[0027] The one in the Fig. 3 and Fig. The load carrier LT shown in Figure 4 has a rigid or non-deformable base plate 30 and a loading floor 32 as the loading surface, between which the sensor element 20 is arranged. The sensor element 20, together with the base plate 30 and the loading floor 32, forms a sensor plate 33. The base plate 30, together with the loading floor 32, is surrounded by side walls 34 of the load carrier LT. In the illustrated embodiment, the sensor element 20 is also interspersed with spacer elements 36 in the region of through-openings 38 of the sensor element 20.

[0028] The spacer elements 36 are supported between the upper side of the base plate 30 and the underside of the loading floor 32. The spacer elements 36 protect the sensor element 20 from a locally excessive weight force G of the load L, since the deformability of the sensor element 20 is limited by the height of the spacer elements 36, which are particularly cylindrical in shape.

[0029] Furthermore, the loading floor 32 has through-openings 40, which are penetrated by (rigid) force transmission elements 42. The force transmission elements 42 project beyond the upper side of the loading floor 32 on the side facing the load L. The weight force G of the load L acts on the sensor element 20 via the force transmission elements 42. For this purpose, the arrangement of the force transmission elements 42, as shown in particular with reference to the Fig.4 can be seen, preferably at equal distances a from one another or in such a way that they are aligned with the segments 26 of the sensor element 20.

[0030] Furthermore, it can be provided that the loading floor 32 is provided with an anti-slip coating 44 which is only shown in some areas.

[0031] The load carrier LT described so far can be modified or altered in a variety of ways without deviating from the inventive concept. For example, the sensor element 20 can also be brought into direct contact with the load L, i.e., the sensor element 20 forms the loading floor 32. However, even in this case, the sensor element 20 is preferably provided with an anti-slip coating 44. Furthermore, several sensor elements 20 can be provided in the region of the sensor plate 33, which are preferably arranged at equal distances from one another in order to detect the weight G of the load L. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2021 210 525 A1

[0002] DE 10 2022 201 311 A1

[0003]

Claims

[1] Load carrier (LT) for transporting and / or storing a load (L), having a loading surface on which the load (L) can be positioned, and having a device for detecting the weight force (G) of the load (L), wherein the device has at least one pressure-sensitive sensor element (20) which is designed to generate an output signal when subjected to the weight force (G), and wherein the at least one pressure-sensitive sensor element (20) is arranged in the region of the loading surface in such a way that the load (L) can be positioned in at least indirect contact with the at least one pressure-sensitive sensor element (20). [2] Load carrier according to claim 1, characterized byin that the at least one sensor element (20) consists of at least three interconnected layers (21, 22, 23), a middle layer (22) made of an electrically insulating and elastically deformable material, preferably made of plastic, in particular PVDF, and two electrically conductive layers (21, 23) arranged on opposite sides of the middle layer (22) and covering the middle layer (22) at least in regions, which can be connected to a voltage source, wherein a voltage signal can be generated when the weight force (G) of the load (L) is applied. [3] Load carrier according to claim 1 or 2, characterized bythat the at least one sensor element (20) is designed as a rectangular sensor element (20) with a plurality of spatially separated and individually evaluable segments (26), or as a strip-shaped sensor rail or as a sensor plate (33) with a plurality of sensor elements (20), which are preferably arranged at equal distances from one another. [4] Load carrier according to one of claims 1 to 3, characterized by that the loading surface or the at least one sensor element (20) has an anti-slip coating (44) for the load (L) on the side facing the load (L). [5] Load carrier according to one of claims 1 to 3, characterized by that the loading area is designed as a loading floor (32), and that the at least one sensor element (20) is arranged on the side of the loading floor (32) facing away from the load (L) between the loading floor (32) and a base plate (30). [6] Load carrier according to claim 5, characterized bythat the loading floor (32) is penetrated by force transmission elements (42) which are designed to transmit the weight force (G) of the load (L) to the at least one sensor element (20). [7] Load carrier according to claim 5 or 6, characterized by that spacer elements (36) are arranged between the base plate (30) and the loading floor (32) to protect the at least one sensor element (20) from an overload caused by the load (L). [8] Load carrier according to one of claims 1 to 7, characterized by that the load carrier (LT) is designed as a storage box (16) with side walls (34). [9] Load carrier according to one of claims 1 to 8, characterized by that the output or voltage signal of the at least one sensor element (20) can be transmitted to a control device (29), preferably wirelessly. [10] Vehicle (10), in particular driverless transport vehicle (12), designed to transport at least one load carrier (LT) which is designed according to one of claims 1 to 9. [11] Vehicle (10) according to claim 10, characterized by that the vehicle (10) comprises the at least one load carrier (LT). [12] Vehicle (10) according to one of claims 10 or 11, characterized by that the vehicle (10) comprises a control device (29) for at least indirectly influencing the driving operation of the vehicle (10) as a function of the output or voltage signals transmitted by the at least one charge carrier (LT).

Images