Transport vehicle

Abstract

A transport vehicle according to the invention for transporting objects comprises a basic frame, a plurality of wheels for moving the transport vehicle on the ground, a drive unit for driving the wheels, and a receiving unit (1) for inductively receiving energy. The transport vehicle also comprises a lifting device, by means of which the receiving unit (1) is movable in a vertical direction (Z) relative to the basic frame between a lower end position and an upper end position, and the lifting device has an electric cylinder (2), which comprises a cylinder block (22), a push rod which is movable in the vertical direction (Z) relative to the cylinder block (22), and an electric motor (21) for driving the push rod relative to the cylinder block (22).

Description

[0001] Transport vehicle

[0002] Description:

[0003] The invention relates to a transport vehicle for transporting objects, comprising a base frame, a plurality of wheels for moving the transport vehicle on a floor, a drive unit for driving the wheels and a receiver unit for inductively receiving energy.

[0004] A transport vehicle of this type for transporting objects is known from German patent application DE 10 2020 002676 B3. The transport vehicle has several wheels, a drive unit for powering the wheels, and an electrical energy storage device. The transport vehicle also has a receiving unit to which energy can be inductively transferred from a charging unit, in particular from a linear conductor. The energy inductively transferred to the receiving unit is used, for example, to charge an electrical energy storage device of the transport vehicle.

[0005] The charging unit is typically located in the floor over which the transport vehicle travels. For the inductive transfer of energy from the charging unit to the receiving unit, a relatively small distance between the two is required. If there are obstacles on the floor, such as stones, these can collide with the receiving unit when the vehicle passes over them. This can damage the receiving unit.

[0006] From DE 102012 022 479 A1, a transport vehicle with a secondary winding for inductive energy storage is known. The secondary winding is arranged on the upper side of the vehicle.

[0007] A device for positioning and drilling crossbars is known from CN 1 15 194473 A. The device has an induction plate that is slidably connected to a sliding frame.

[0008] From CN 1 04442 518 A, a driverless transport vehicle is known that can be automatically attached to worktable surfaces of different heights. The autonomous vehicle has a liftable, load-bearing table surface.

[0009] ISI \ EIDOPAT 07.07.2025 The invention is based on the objective of further developing a transport vehicle for the transport of objects.

[0010] The object of the invention is achieved by a transport vehicle having the features specified in claim 1. Advantageous embodiments and further developments are the subject of the dependent claims.

[0011] A transport vehicle according to the invention for transporting objects comprises a base frame, a plurality of wheels for moving the transport vehicle on a floor, a drive unit for driving the wheels, and a receiver unit for inductively receiving energy. The transport vehicle also includes a lifting device by means of which the receiver unit can be moved vertically relative to the base frame between a lower end position and an upper end position. The lifting device has an electric cylinder comprising a cylinder block, a push rod movable vertically relative to the cylinder block, and an electric motor for driving the push rod relative to the cylinder block.

[0012] When the ground is level and free of obstacles, the receiving unit moves to its lower end position, positioned directly above a charging unit. In this position, the receiving unit is inductively coupled to the charging unit, allowing energy to be transferred between them. The lifting device allows the receiving unit to be raised—moved vertically away from the ground to its upper end position—if an obstacle, such as a stone, is detected. This prevents collisions and damage to the receiving unit, increasing safety during transport vehicle operation and reducing the failure rate. The electric cylinder enables precise control of the receiving unit's vertical movement relative to the base frame between its lower and upper end positions.

[0013] According to an advantageous embodiment of the invention, the lifting device comprises an upper frame and a lower frame. The upper frame is fixedly connected to the base frame, and the lower frame is fixedly connected to the receiving unit. A movement of the lower frame relative to the upper frame in the vertical direction thus corresponds to a movement of the receiving unit relative to the base frame in the vertical direction.

[0014] According to an advantageous embodiment of the invention, the upper frame is connected to the cylinder block and the electric motor in a displacement-resistant manner, and the lower frame is connected to the push rod in a displacement-resistant manner. When the electric motor drives the push rod vertically relative to the cylinder block, the receiving unit moves vertically relative to the base frame.

[0015] According to an advantageous embodiment of the invention, the lifting device has several guide rods extending vertically and which are connected to the substructure in a displacement-resistant manner. The guide rods are movable in the vertical direction relative to the upper frame. The guide rods form a linear guide for the substructure during movement in the vertical direction relative to the upper frame.

[0016] According to an advantageous embodiment of the invention, the support structure is arranged vertically below the upper frame. Thus, the support structure is positioned vertically between the floor and the upper frame.

[0017] According to an advantageous embodiment of the invention, the lifting device has a lower sensor for detecting the lower end position of the receiving unit relative to the base frame in the vertical direction and an upper sensor for detecting the upper end position of the receiving unit relative to the base frame in the vertical direction. The end positions of the receiving unit can be detected by means of the two sensors, and the electric motor of the electric cylinder can thereby be controlled.

[0018] According to an advantageous embodiment of the invention, the lifting device comprises a metal plate which is connected to the receiving unit in a displacement-resistant manner. The lower and upper sensors are designed as inductive sensors for detecting the metal plate, and both are connected to the base frame in a displacement-resistant manner. Thus, when the receiving unit moves vertically relative to the base frame, the metal plate also moves vertically relative to the sensors.

[0019] According to an advantageous embodiment of the invention, detect in the upper

[0020] When the receiving unit is in its end position, the lower sensor detects the metal sheet and the upper sensor detects the metal sheet; when the receiving unit is in its lower end position, neither sensor detects the metal sheet; and when the receiving unit is in an intermediate position, only the lower sensor detects the metal sheet.

[0021] According to an advantageous embodiment of the invention, the lifting device includes an ammeter for measuring the current flowing through the electric motor. Measuring the current flowing through the electric motor enables monitoring of the lifting device for stiffness or difficulty in its operation.

[0022] According to an advantageous embodiment of the invention, the transport vehicle comprises an electrical energy storage device for supplying the drive unit and the lifting device, which can be supplied with electrical energy by the receiving unit.

[0023] According to an advantageous embodiment of the invention, the transport vehicle is designed as an autonomously driving transport vehicle and includes a control unit for controlling the drive unit and the lifting device.

[0024] The invention is not limited to the combination of features stated in the claims. For a person skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent, in particular from the problem statement and / or the problem arising from a comparison with the prior art.

[0025] The invention will now be explained in more detail with reference to the illustrations. The invention is not limited to the embodiments shown in the illustrations. The illustrations only depict the subject matter of the invention schematically. They show:

[0026] Figure 1: a perspective view of a lifting device for a transport vehicle.

[0027] Figure 1 shows a perspective view of a lifting device for a transport vehicle. The lifting device has an upper frame 5 and a lower frame 6. The lower frame 6 is movable relative to the upper frame 5 in a vertical direction Z. A transverse direction Y runs perpendicular to the vertical direction Z. A longitudinal direction X runs perpendicular to the vertical direction Z and perpendicular to the transverse direction Y.

[0028] A receiving unit 1 is arranged on the component 6. The component 6 is connected to the receiving unit 1 in a way that prevents displacement. The component 6 is arranged in the vertical direction Z below the upper frame 5. The component 6 is arranged in the vertical direction Z between the receiving unit 1 and the upper frame 5.

[0029] The lifting device has several, in this case four, guide rods 3, which extend in the vertical direction Z. The guide rods 3 are connected to the support structure 6 in a way that prevents displacement. The guide rods 3 are thus also connected to the receiving unit 1 in a way that prevents displacement. The guide rods 3 are movable relative to the upper frame 5 in the vertical direction Z. The guide rods 3 extend through the upper frame 5.

[0030] The lifting device includes an electric cylinder 2. The electric cylinder 2 comprises a cylinder block 22 and a push rod movable relative to the cylinder block 22 in the vertical direction Z. The push rod is partially located inside the cylinder block 22 and partially protrudes from it. The electric cylinder 2 also includes an electric motor 21 for driving the push rod relative to the cylinder block 22 in the vertical direction Z.

[0031] The upper frame 5 is fixedly connected to the cylinder block 22 and to the electric motor 21. The lower frame 6 is fixedly connected to the push rod. When the electric motor 21 drives the push rod out of the cylinder block 22, the lower frame 6 moves away from the upper frame 5 in the vertical direction Z. When the electric motor 21 drives the push rod inward into the cylinder block 22, the lower frame 6 moves closer to the upper frame 5 in the vertical direction Z.

[0032] The transport vehicle, not shown here, is used to transport objects. In this case, the transport vehicle is an autonomous vehicle. The transport vehicle is located on a level surface.

[0033] The transport vehicle comprises a base frame. The base frame has an approximately rectangular cross-section and extends predominantly in the longitudinal direction X and the transverse direction Y. The longitudinal direction X corresponds at least approximately to the usual direction of travel of the transport vehicle.

[0034] The longitudinal direction X and the transverse direction Y represent horizontal directions and run parallel to the ground on which the transport vehicle is located. Any direction perpendicular to the vertical direction Z represents a horizontal direction. The vertical direction Z is perpendicular to the flat ground.

[0035] The transport vehicle comprises several wheels that are rotatable relative to the base frame. The transport vehicle can be moved on the ground by means of these wheels. In this case, the transport vehicle comprises two front wheels, which are offset from each other in the transverse direction Y, and two rear wheels, which are also offset from each other in the transverse direction Y. The front wheels are offset from the rear wheels in the longitudinal direction X.

[0036] When the transport vehicle travels in its normal direction of travel, i.e., in the longitudinal direction X, the wheels rotate around axes of rotation that extend in the transverse direction Y. When the transport vehicle travels around a curve, the axes of rotation of the front wheels, for example, pivot around a pivot axis extending in the vertical direction Z. The axes of rotation of the front wheels then extend in a horizontal direction that is inclined relative to the longitudinal direction X and relative to the transverse direction Y.

[0037] The transport vehicle includes a drive unit for powering the wheels. It also includes an electrical energy storage device to supply power to the drive unit and a control unit to manage the drive unit. The drive unit comprises, for example, a traction motor and a transmission and drives some or all of the wheels. The transport vehicle also has a steering mechanism (not shown) for steering the wheels. The steering mechanism can also be controlled by the control unit.

[0038] The transport vehicle also includes the lifting device shown here. The upper frame 5 of the lifting device is connected to the base frame of the transport vehicle in a way that prevents displacement. For example, the upper frame 5 is bolted to the base frame 12.

[0039] The electrical energy storage device also serves to supply power to the lifting device, in particular to power the electric motor 21 of the electric cylinder. The control unit also serves to control the lifting device, in particular to control the electric motor 21 of the electric cylinder.

[0040] The transport vehicle also includes the receiving unit 1, which is attached to the lifting device's component 6. Energy can be inductively transferred to the receiving unit 1 from a charging unit. The energy inductively transferred from the charging unit to the receiving unit 1 is used, for example, to charge the transport vehicle's electrical energy storage system. The receiving unit 1 can be moved in the vertical direction Z relative to the base frame by means of the lifting device.

[0041] The receiving unit 1 comprises a transformer head with a secondary coil. The charging unit is configured, for example, as a current-carrying primary conductor laid in the ground beneath the transport vehicle. Alternatively, the charging unit can also be configured as a current-carrying primary coil laid in the ground beneath the transport vehicle. The charging unit is positioned close to the ground surface. The secondary coil of the transformer head of receiving unit 1 can be inductively coupled to the charging unit.

[0042] When the unit 6 moves away from the upper frame 5 in the vertical direction Z, the receiving unit 1 moves downwards in the vertical direction Z, i.e., towards the ground. When the unit 6 moves closer to the upper frame 5 in the vertical direction Z, the receiving unit 1 moves upwards in the vertical direction Z, i.e., away from the ground.

[0043] When the electric motor 21 drives the push rod out of the cylinder block 22, the receiving unit 1 moves downwards in the vertical direction Z, i.e., towards the ground and away from the base frame. When the electric motor 21 drives the push rod inwards into the cylinder block 22, the receiving unit 1 moves upwards in the vertical direction Z, i.e., away from the ground and towards the base frame.

[0044] By means of the lifting device, the receiving unit 1 can thus be moved relative to the base frame between a lower end position and an upper end position in the vertical direction Z.

[0045] In the lower end position, the distance between the base frame and the receiving unit 1 in the vertical direction Z is at its maximum. The receiving unit 1 is thus located in close proximity to the ground, particularly above a charging unit positioned there. The receiving unit 1 is arranged such that the secondary coil is inductively coupled to the charging unit. This allows energy to be transferred from the charging unit to the receiving unit 1.

[0046] In the upper end position, the distance between the base frame and the receiving unit 1 in the vertical direction Z is minimal. The receiving unit 1 is therefore at its maximum distance from the ground. The transport vehicle thus has maximum ground clearance.

[0047] The lifting device has a lower sensor 41 for detecting the lower end position of the receiving unit 1 relative to the base frame in the vertical direction Z. The lower sensor 41 is designed as an inductive sensor. The lower sensor 41 is connected to the base frame and to the upper frame 5 in a way that prevents displacement.

[0048] The lifting device has an upper sensor 42 for detecting the upper end position of the receiving unit 1 relative to the base frame in the vertical direction Z. The upper sensor 42 is designed as an inductive sensor. The upper sensor 42 is connected to the base frame and to the upper frame 5 in a way that prevents displacement.

[0049] The lifting device has a sheet metal plate 45 which is connected to the receiving unit 1 and to the subframe 6 in a displacement-resistant manner. The sheet metal plate 45 is detectable by the lower sensor 41 and by the upper sensor 42.

[0050] When receiver unit 1 is in the upper end position, the lower sensor 41 and the upper sensor 42 detect the sheet metal 45. When receiver unit 1 is in the lower end position, neither sensor 41 nor 42 detects the sheet metal 45. When receiver unit 1 is in an intermediate position, only the lower sensor 41 detects the sheet metal 45.

[0051] When the electric motor 21 drives the push rod in the direction out of the cylinder block 22, and the receiving unit 1 moves downwards in the vertical direction Z, a lower target current flows through the electric motor 21 if the lifting device is intact.

[0052] When the electric motor 21 drives the push rod in the direction into the cylinder block 22, and the receiving unit 1 moves upwards in the vertical direction Z, an upper target current flows through the electric motor 21 if the lifting device is intact.

[0053] The lifting device includes an ammeter for measuring the current flowing through the electric motor 21. Measuring the current flowing through the electric motor allows monitoring of the lifting device, particularly for stiffness or difficulty in its operation.

[0054] If the ammeter measures a current flowing through the electric motor 21 that is greater than the respective target current, then there is a stiffness in the lifting device, for example one of the guide rods 3 is bent.

[0055] If the ammeter measures a current flowing through the electric motor 21 that is smaller than the respective target current, then, for example, the receiving unit 1 is not present.

[0056] Reference symbol list

[0057] 1 receiver unit 2 electric cylinders

[0058] 3 Guide rod

[0059] 5 upper frames

[0060] 6 subframes

[0061] 21 Electric motor 22 Cylinder block

[0062] 41 lower sensor

[0063] 42 upper sensor

[0064] 45 sheet metal

[0065] X Longitudinal direction Y Transverse direction

[0066] Z Vertical direction

Claims

Claims:

1. Transport vehicle for transporting objects, comprising a base frame, a plurality of wheels for moving the transport vehicle on a floor, a drive unit for driving the wheels and a receiving unit (1) for inductively receiving energy, characterized in that the transport vehicle comprises a lifting device by means of which the receiving unit (1) is movable relative to the base frame between a lower end position and an upper end position in a vertical direction (Z), and that the lifting device has an electric cylinder (2) comprising a cylinder block (22), a push rod movable relative to the cylinder block (22) in a vertical direction (Z) and an electric motor (21) for driving the push rod relative to the cylinder block (22).

2. Transport vehicle according to claim 1, characterized in that the lifting device (10) has an upper frame (5) and a lower frame (6), and that the upper frame (5) is connected to the base frame in a displaceable manner, and that the lower frame (6) is connected to the receiving unit (1) in a displaceable manner.

3. Transport vehicle according to claim 2, characterized in that the upper frame (5) is connected to the cylinder block (22) and to the electric motor (21) in a manner that prevents displacement, and that the undercarriage (6) is connected to the push rod in a manner that prevents displacement.

4. Transport vehicle according to one of claims 2 to 3, characterized in that the lifting device has several guide rods (3) which extend in the vertical direction (Z) and which are connected to the undercarriage (6) in a displaceable manner, and that the guide rods (3) are movable relative to the upper frame (5) in the vertical direction (Z).

5. Transport vehicle according to one of claims 2 to 4, characterized in that the undercarriage (6) is arranged in the vertical direction (Z) below the upper frame (5).

6. Transport vehicle according to one of the preceding claims, characterized in that the lifting device has a lower sensor (41) for detecting the lower end position of the receiving unit (1) relative to the base frame in the vertical direction (Z) and an upper sensor (42) for detecting the upper end position of the receiving unit (1) relative to the base frame in the vertical direction (Z).

7. Transport vehicle according to claim 6, characterized in that the lifting device has a sheet (45) which is connected to the receiving unit (1) in a displaceable manner, and that the lower sensor (41) and the upper sensor (42) are designed as inductive sensors for detecting the sheet (45), and that the lower sensor (41) and the upper sensor (42) are connected to the base frame in a displaceable manner.

8. Transport vehicle according to claim 7, characterized in that when the receiving unit (1) is in the upper end position, the lower sensor (41) and the upper sensor (42) detect the sheet metal (45), and that when the receiving unit (1) is in the lower end position, neither of the sensors (41, 42) detects the sheet metal (45), and that when the receiving unit (1) is in an intermediate position, only the lower sensor (41) detects the sheet metal (45).

9. Transport vehicle according to one of the preceding claims, characterized in that the lifting device has an ammeter for measuring a current flowing through the electric motor (21).

10. Transport vehicle according to one of the preceding claims, characterized in that the transport vehicle comprises an electrical energy storage device for supplying the drive unit and the lifting device, which can be supplied with electrical energy by the receiving unit (1).

11. Transport vehicle according to one of the preceding claims, characterized in that the transport vehicle is designed as an autonomously driving transport vehicle and comprises a control device for controlling the drive unit and the lifting device.

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