Lifting device and transport vehicle

The lifting device for transport vehicles achieves stability under lateral accelerations and minimizes drive unit space by employing a dual scissor mechanism and compact drive unit design, addressing stability and space constraints in existing lifting devices.

WO2025223764A1PCT designated stage Publication Date: 2025-10-30SEW EURODRIVE GMBH & CO KG
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Patent Information

Application Number
PCT/EP2025/057924
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-04-22
Filing Date
2025-03-24
Publication Date
2025-10-30

AI Technical Summary

Technical Problem

Existing lifting devices for transport vehicles lack stability under lateral accelerations, such as those experienced during braking or cornering, and require significant installation space for drive units.

Method used

A lifting device with a primary and secondary scissor mechanism, where the primary scissor axis is inclined relative to the secondary scissor axis, enhancing stability under lateral accelerations, and a compact drive unit design using an electric motor and spindle mechanism to minimize space requirements.

Benefits of technology

The solution provides enhanced stability and reduced installation space for the drive unit, ensuring stable operation during lateral movements and efficient use of vehicle space.

✦ Generated by Eureka AI based on patent content.

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Abstract

A lifting device according to the invention, in particular for a transport vehicle, comprises an upper frame, a lower frame and at least one primary scissor lift, which has a first primary lever and a second primary lever, which intersect at a primary scissor axis. The primary scissor lift is designed and arranged in such a way that a distance between the upper frame and the lower frame changes in a vertical direction as a result of a pivoting movement of the first primary lever relative to the second primary lever about the primary scissor axis. The lifting device also comprises at least one secondary scissor lift, which has a first secondary lever and a second secondary lever, which intersect at a secondary scissor axis. The secondary scissor lift is designed and arranged in such a way that the distance between the upper frame and the lower frame changes in the vertical direction as a result of a pivoting movement of the first secondary lever relative to the second secondary lever about the secondary scissor axis. The primary scissor axis runs at an angle to the secondary scissor axis. A transport vehicle according to the invention, in particular a driverless transport vehicle, comprises a drive device, an electrical energy store for supplying the drive device, and a control device for controlling the drive device, and a lifting device according to the invention.
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Description

[0001] Lifting device and transport vehicle

[0002] Description:

[0003] The invention relates to a lifting device, in particular for a transport vehicle, comprising an upper frame, a substructure, and at least one primary lifting scissor mechanism, the latter having a first primary arm and a second primary arm intersecting at a primary scissor axis, wherein the primary lifting scissor mechanism is designed and arranged such that a pivoting movement of the first primary arm relative to the second primary arm about the primary scissor axis changes the distance between the upper frame and the substructure in a vertical direction. The invention relates to a transport vehicle comprising a lifting device according to the invention.

[0004] From DE 10 2021 004 855 A1, a lifting device for a transport vehicle is known, which has a scissor frame comprising a pair of first arms and second arms which cross at a scissor axis and are pivotable about the scissor axis, an upper frame and a support structure, and which is designed such that a pivoting movement of the first arms relative to the second arms about the scissor axis changes the distance of the upper frame to the support structure in a vertical direction.

[0005] From DE 10 2010 046 489 B3, a vehicle seat with a scissor mechanism is known. The scissor mechanism comprises a pair of first arms and second arms, which intersect at a scissor axis and are pivotable about this axis, an upper frame, and a support structure. By pivoting the first arms relative to the second arms about the scissor axis, the distance between the upper frame and the support structure changes, and thus the height of the scissor mechanism changes.

[0006] From DE 10 2021 207 173 A1, a patient positioning table is known which has two scissor frames. A positioning table connected to the scissor frames can be moved vertically by means of a lifting device.

[0007] DE 10 2013 009 705 A1 discloses a lifting table with four scissor lifts. A frame section resting on the scissor lifts is vertically movable by means of a linear drive. DE 10 2013 113 729 A1 discloses a transport vehicle. The transport vehicle comprises two lifting devices, which are designed as scissor lift tables.

[0008] From EP 2 208 675 A1, a gripping machine with a machine housing is known. The machine housing is arranged on a height-adjustable scissor lift platform.

[0009] The invention is based on the objective of further developing a lifting device, in particular for a transport vehicle, as well as a transport vehicle, in particular a driverless transport vehicle.

[0010] The object of the invention is achieved by a lifting device having the features specified in claim 1. Advantageous embodiments and further developments are the subject of the dependent claims. The object of the invention is also achieved by a transport vehicle having the features specified in claim 11.

[0011] A lifting device according to the invention, particularly for a transport vehicle, comprises an upper frame, a support structure, and at least one primary lifting scissor mechanism, which has a first primary arm and a second primary arm that intersect at a primary scissor axis. The primary lifting scissor mechanism is designed and arranged such that a pivoting movement of the first primary arm relative to the second primary arm about the primary scissor axis changes the distance between the upper frame and the support structure in a vertical direction. The lifting device also comprises at least one secondary lifting scissor mechanism, which has a first secondary arm and a second secondary arm that intersect at a secondary scissor axis.The secondary lifting scissor mechanism is designed and arranged such that a pivoting movement of the first secondary rocker arm relative to the second secondary rocker arm around the secondary scissor axis changes the distance of the upper frame to the substructure in the vertical direction. The primary scissor axis is inclined relative to the secondary scissor axis.

[0012] The arrangement of the lifting scissors according to the invention allows for an even load distribution. Furthermore, the stability of the lifting device is significantly increased under lateral accelerations, which occur, for example, when a transport vehicle brakes or corners. According to a preferred embodiment of the invention, the primary scissor axis extends in a longitudinal direction, and the secondary scissor axis extends in a transverse direction. The transverse direction extends perpendicular to the vertical direction. The longitudinal direction extends perpendicular to both the vertical and transverse directions. The primary scissor axis is perpendicular to the secondary scissor axis. This further increases the stability of the lifting device under lateral accelerations, particularly when a transport vehicle brakes or corners.

[0013] According to an advantageous embodiment of the invention, the first primary rocker arm is articulated at a lower end to the substructure and is pivotable relative to the substructure. The first primary rocker arm is guided at an upper end on the upper frame in a transverse direction by means of a roller. The second primary rocker arm is articulated at an upper end to the upper frame and is pivotable relative to the upper frame.

[0014] According to an advantageous embodiment of the invention, the primary lifting scissor has a drive unit for pivoting the first primary rocker arm relative to the second primary rocker arm about the primary scissor axis.

[0015] According to an advantageous embodiment of the invention, the drive unit comprises an electric motor which rotates a spindle on which a spindle nut is rotatably mounted. The second primary rocker arm is articulated at a lower end to the spindle nut and is pivotable relative to the spindle nut. This results in a relatively small installation space required for the drive unit.

[0016] According to an advantageous embodiment of the invention, the spindle is rotatable relative to the workpiece about a spindle axis, and the spindle axis extends in the transverse direction. By rotating the spindle about the spindle axis, the spindle nut is moved translationally along the spindle axis. This results in a relatively small installation space required for the drive unit.

[0017] According to an advantageous embodiment of the invention, the drive unit comprises at least one sensor for detecting the position of the spindle nut relative to the spindle. The position of the spindle nut relative to the spindle corresponds to the stroke height of the lifting device, i.e., the distance of the upper frame to the workpiece in the vertical direction. The sensor is, for example, designed as an inductive, non-contact sensor. The sensor is, for example, designed as a rotary encoder that detects the revolutions of the electric motor of the drive unit and calculates the stroke height from this.

[0018] According to an advantageous embodiment of the invention, the drive unit comprises a front sensor for detecting a front end position of the spindle nut relative to the spindle, a rear sensor for detecting a rear end position of the spindle nut relative to the spindle, and a middle sensor for detecting an intermediate position of the spindle nut relative to the spindle. Thus, a lower end position, an upper end position, and an intermediate position of the upper frame relative to the operator can be detected.

[0019] According to an advantageous embodiment of the invention, the first secondary rocker arm is articulated at a lower end to the frame and pivotable relative to the frame. The first secondary rocker arm is guided longitudinally at an upper end by means of a roller on the upper frame. The second secondary rocker arm is articulated at an upper end to the upper frame and pivotable relative to the upper frame. The second secondary rocker arm is guided longitudinally at a lower end by means of a roller on the frame. An additional drive unit for the secondary lifting scissors is not required.

[0020] According to an advantageous embodiment of the invention, the lifting device comprises two primary lifting scissors, each having a first primary arm and a second primary arm that intersect at a primary scissor axis, and the lifting device comprises two secondary lifting scissors, each having a first secondary arm and a second secondary arm that intersect at a secondary scissor axis. Preferably, the primary scissor axes are parallel and offset from each other or are aligned with each other. Preferably, the secondary scissor axes are parallel and offset from each other or are aligned with each other.

[0021] A transport vehicle according to the invention, in particular a driverless transport vehicle, comprises a drive unit, an electrical energy storage device for supplying the drive unit, a control unit for controlling the drive unit, and a lifting device according to the invention. The invention is not limited to the combination of features of the claims. For those 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.

[0022] 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:

[0023] Figure 1: a perspective view of a lifting device,

[0024] Figure 2: a view of the lifting device from below,

[0025] Figure 3: a first side view of the lifting device at minimum lifting height,

[0026] Figure 4: a first side view of the lifting device at maximum lifting height,

[0027] Figure 5: a second side view of the lifting device at minimum lifting height and

[0028] Figure 6: a second side view of the lifting device at maximum lifting height.

[0029] Figure 1 shows a perspective view of a lifting device for a transport vehicle. The lifting device comprises a lower frame 30 and an upper frame 40. The upper frame 40 is arranged vertically Z above the lower frame 30 and is movable vertically Z relative to the lower frame 30. The upper frame 40 serves to support a load to be transported.

[0030] In the illustration shown here, the subframe 30 has several separately arranged parts. The individual parts of the subframe 30 are rigidly attached to the transport vehicle (not shown here). The individual parts of the subframe 30 are fixed in position relative to each other and thus always maintain their position relative to one another.

[0031] The lifting device comprises two primary lifting scissor mechanisms 10. The primary lifting scissor mechanisms 10 are arranged offset from each other in a longitudinal direction X. The lifting device comprises two secondary lifting scissor mechanisms 20. The secondary lifting scissor mechanisms 20 are arranged offset from each other in a transverse direction Y.

[0032] The transverse direction Y is perpendicular to the vertical direction Z. The longitudinal direction X is perpendicular to both the transverse direction Y and the vertical direction Z. The primary lifting scissors 10 each have a first primary rocker arm 11 and a second primary rocker arm 12. The first primary rocker arm 11 and the second primary rocker arm 12 each intersect at a primary scissor axis 15 and are pivotable relative to each other about the primary scissor axis 15. The primary scissor axes 15 of the primary lifting scissors 10 extend in the longitudinal direction X. The primary scissor axes 15 are parallel to each other, offset from each other, or aligned with each other.

[0033] A pivoting movement of the first primary swing arms 11 relative to the second primary swing arms 12 about the primary scissor axes 15 changes the distance between the upper frame 40 and the lower frame 30 in the vertical direction Z. The distance between the upper frame 40 and the lower frame 30 in the vertical direction Z is also referred to as the lifting height of the lifting device.

[0034] The primary lifting scissors 10 each have a drive unit 50 for pivoting the first primary rocker arm 11 relative to the second primary rocker arm 12 about the primary scissor axis 15. The drive units 50 of the primary lifting scissors 10 thus serve to adjust the lifting height of the lifting device.

[0035] The drive units 50 of the primary lifting scissors 10 each comprise an electric motor, a spindle, and a spindle nut. The spindle nut is rotatably mounted on the spindle. The spindle is rotatable relative to the support structure 30 about a spindle axis. The spindle axis extends in the transverse direction Y. The electric motors of the drive units 50 are fixedly mounted on the support structure 30.

[0036] The electric motor drives the spindle rotationally. By rotating the spindle around its axis, the spindle nut is moved translationally along the spindle axis. The second primary arms 12 are each articulated at one lower end to one of the spindle nuts and are pivotable relative to the spindle nut about a pivot axis extending in the longitudinal direction X.

[0037] When the electric motor drives the spindle, the spindle is rotated around the spindle axis relative to the support 30. This causes the spindle nut to move translationally along the spindle axis. In doing so, the second primary rocker arm 12 pivots relative to the spindle nut. This, in turn, causes the first primary rocker arm 11 to pivot around the primary scissor axis 15 relative to the second primary rocker arm 12. This changes the stroke height of the lifting device.

[0038] Figure 2 shows a view of the lifting device from below in the vertical direction Z. The secondary lifting scissors 20 each have a first secondary rocker arm 21 and a second secondary rocker arm 22. The first secondary rocker arm 21 and the second secondary rocker arm 22 each intersect at a secondary scissor axis 25 and are pivotable relative to each other about the secondary scissor axis 25.

[0039] The secondary scissor axes 25 of the secondary lifting scissors 20 extend in the transverse direction Y. The secondary scissor axes 25 run parallel to each other, offset from each other, or are aligned with each other. The primary scissor axes 15 thus run perpendicular to the secondary scissor axes 25.

[0040] A pivoting movement of the first secondary arms 21 relative to the second secondary arms 22 about the secondary scissor axes 25 also changes the distance between the upper frame 40 and the lower frame 30 in the vertical direction Z, and thus the lifting height of the lifting device. Likewise, a change in the lifting height of the lifting device causes a pivoting movement of the first secondary arms 21 relative to the second secondary arms 22 about the secondary scissor axes 25.

[0041] Figure 3 shows a first side view of the lifting device in the longitudinal direction X at minimum lifting height. The upper frame 40 is in a lower end position, i.e., in the vertical direction Z close to the support 30. The spindle nut is in a forward end position.

[0042] The first primary swing arms 11 are hinged at a lower end to the support 30 and are pivotable relative to the support 30. The first primary swing arms 11 are guided at an upper end by means of a roller on the upper frame 40 so as to be movable in the transverse direction Y. The second primary swing arms 12 are hinged at an upper end to the upper frame 40 and are pivotable relative to the upper frame 40.

[0043] Figure 4 shows a first side view of the lifting device in the longitudinal direction X at maximum lifting height. The upper frame 40 is in an upper end position, i.e., furthest away from the support 30 in the vertical direction Z. The spindle nut is in a rear end position.

[0044] Figure 5 shows a second side view of the lifting device in the transverse direction Y at minimum lifting height. The upper frame 40 is in a lower end position, i.e., in the vertical direction Z close to the support 30.

[0045] Figure 6 shows a second side view of the lifting device in the transverse direction Y at maximum lifting height. The upper frame 40 is in an upper end position, i.e., furthest away from the support 30 in the vertical direction Z.

[0046] The first secondary swing arms 21 are hinged at a lower end to the support 30 and are pivotable relative to the support 30. The first secondary swing arms 21 are guided at an upper end by means of a roller on the upper frame 40 in the longitudinal direction X.

[0047] The second secondary swing arms 22 are hinged at one upper end to the upper frame 40 and are pivotable relative to the upper frame 40. The second secondary swing arms 22 are guided at one lower end by means of a roller on the support 30 in the longitudinal direction X.

[0048] Reference symbol list

[0049] 10 primary lifting scissor 11 first primary swing arm

[0050] 12 second primary swingarm

[0051] 15 primary scissor axis

[0052] 20 secondary lifting scissors

[0053] 21 first secondary swing arm 22 second secondary swing arm

[0054] 25 secondary scissor axis

[0055] 30 subframes

[0056] 40 upper frames

[0057] 50 Drive unit X Longitudinal direction

[0058] Y transverse direction z vertical direction

Claims

Patent claims:

1. Lifting device, in particular for a transport vehicle, comprising an upper frame (40), a support structure (30) and at least one primary lifting scissor (10) which has a first primary rocker arm (11) and a second primary rocker arm (12) which intersect at a primary scissor axis (15), wherein the primary lifting scissor (10) is designed and arranged such that a pivoting movement of the first primary rocker arm (11) relative to the second primary rocker arm (12) about the primary scissor axis (15) changes the distance of the upper frame (40) to the support structure (30) in a vertical direction (Z), characterized in that the lifting device comprises at least one secondary lifting scissor (20) which has a first secondary rocker arm (21) and a second secondary rocker arm (22) which intersect at a secondary scissor axis (25), and that the secondary lifting scissor (20) is designed and arranged such thatthat by a pivoting movement of the first secondary swing arm (21) relative to the second secondary swing arm (22) about the secondary scissor axis (25) the distance of the upper frame (40) to the undercarriage (30) changes in the vertical direction (Z), and that the primary scissor axis (15) is inclined to the secondary scissor axis (25).

2. Lifting device according to claim 1, characterized in that the primary scissor axis (15) extends in a longitudinal direction (X), and that the secondary scissor axis (25) extends in a transverse direction (Y).

3. Lifting device according to one of the preceding claims, characterized in that the first primary rocker arm (11) is articulated at a lower end to the subframe (30) and is pivotable relative to the subframe (30), and that the first primary rocker arm (11) is movably guided at an upper end on the upper frame (40) by means of a roller in a transverse direction (Y), and that the second primary rocker arm (12) is articulated at an upper end to the upper frame (40) and is pivotable relative to the upper frame (40).

4. Lifting device according to one of the preceding claims, characterized in that the primary lifting scissor (10) has a drive unit (50) for pivoting the first primary rocker arm (11) relative to the second primary rocker arm (12) about the primary scissor axis (15).

5. Lifting device according to claim 4, characterized in that the drive unit (50) comprises an electric motor which rotatably drives a spindle on which a spindle nut is rotatably mounted, and that the second primary rocker arm (12) is articulated at a lower end to the spindle nut and is pivotable relative to the spindle nut.

6. Lifting device according to claim 5, characterized in that the spindle is rotatable relative to the support (30) about a spindle axis, and that the spindle axis extends in the transverse direction (Y), and that by rotating the spindle about the spindle axis the spindle nut is moved translationally along the spindle axis.

7. Lifting device according to one of claims 5 to 6, characterized in that the drive unit (50) comprises at least one sensor for detecting a position of the spindle nut relative to the spindle.

8. Lifting device according to one of claims 5 to 7, characterized in that the drive unit (50) comprises a front sensor for detecting a front end position of the spindle nut relative to the spindle, a rear sensor for detecting a rear end position of the spindle nut relative to the spindle and a middle sensor for detecting an intermediate position of the spindle nut relative to the spindle.

9. Lifting device according to one of the preceding claims, characterized in that the first secondary rocker arm (21) is articulated at a lower end to the subframe (30) and is pivotable relative to the subframe (30), and that the first secondary rocker arm (21) is movably guided at an upper end on the upper frame (40) by means of a roller in the longitudinal direction (X), and that the second secondary rocker arm (22) is articulated at an upper end to the upper frame (40) and is pivotable relative to the upper frame (40), and that the second secondary rocker arm (22) is movably guided at a lower end on the subframe (30) by means of a roller in the longitudinal direction (X).

10. Lifting device according to one of the preceding claims, characterized in that the lifting device comprises two primary lifting scissors (10), each having a first primary rocker arm (11) and a second primary rocker arm (12), each intersecting at a primary scissor axis (15), and that the lifting device comprises two secondary lifting scissors (20), each having a first secondary rocker arm (21) and a second secondary rocker arm (22), each intersecting at a secondary scissor axis (25).

11. Transport vehicle, in particular driverless transport vehicle, comprising a drive unit, an electrical energy storage device for supplying the drive unit, a control unit for controlling the drive unit and a lifting device according to one of the preceding claims.

Citation Information

Patent Citations

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