Crane device and parallel wire drive mechanism

Abstract

To provide a crane device capable of reducing an upper space required for operation thereof.SOLUTION: A crane device includes a suspension tool 28, a plurality of wires 30 for supporting the suspension tool 28, and a plurality of wire drive mechanism 32 performing winding and rewinding of each of the plurality of wires 30. Connection portions between the suspension tool 28 and the plurality of wires 30 are dispersed on a lower end side and an upper end side of the suspension tool 28. The suspension tool 28 can be expanded and contracted between the connection portion on the lower end side and the connection portion on the upper end side.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a crane and a parallel wire drive mechanism.

Background Art

[0002] Crane devices such as ceiling cranes are known. The crane device lifts a lifting object with a lifting tool and transports the lifting object by moving the lifting tool in the horizontal direction. Crane devices with various structures are provided, and one of them is a crane device using a parallel wire drive mechanism.

[0003] Patent Document 1 discloses a parallel wire drive mechanism. This parallel wire drive mechanism includes (N + 1) wires connected to a control object and (N + 1) wire drive mechanisms for feeding out or winding up these wires, and the connection points of the (N + 1) wires and the control object are dispersed on the lower end side and the upper end side of the control object, realizing the N-degree-of-freedom movement of the control object.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] FIG. 1 is a diagram for explaining the problems of a conventional parallel wire drive mechanism as described in Patent Document 1. The connection points between the object to be controlled 102 and the wires 104 extending from each of a plurality of wire drive mechanisms (not shown) are distributed at the lower end 102a and the upper end 102b of the object to be controlled 102. A hanging portion (not shown) such as a hook or a robot hand is attached to the lower end 102a of the object to be controlled 102. In this parallel wire drive mechanism, the operating area R of the lower end 102a of the object to be controlled 102, and thus the hanging portion, requires an upper space S that is substantially the same size. When a crane device equipped with such a parallel wire drive mechanism is installed in a building such as a factory, it significantly consumes the space inside the building.

[0006] The present invention has been made in view of such circumstances, and an exemplary object of one aspect thereof is to provide a crane device capable of reducing the upper space required for operation.

Means for Solving the Problems

[0007] In order to solve the above problems, a crane device according to an aspect of the present invention includes a suspension tool, a plurality of wires that support the suspension tool, and a plurality of wire drive mechanisms that respectively feed out and wind up the plurality of wires. The connection points between the suspension tool and the plurality of wires are distributed on one end side and the other end side of the hanging portion, and the suspension tool is stretchable between the connection point on the one end side and the connection point on the other end side.

[0008] Any combination of the above components, or those obtained by mutually replacing the components and expressions of the present invention between methods, devices, systems, etc., are also effective as aspects of the present invention.

Effects of the Invention

[0009] According to the present invention, it is possible to provide a crane device capable of reducing the upper space required for operation.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0011] Hereinafter, the same or equivalent components and members shown in each drawing are denoted by the same reference numerals, and repeated explanations are omitted as appropriate. Also, the dimensions of the members in each drawing are appropriately enlarged or reduced for easy understanding. In addition, some members that are not important for explaining the embodiment in each drawing are omitted from the display.

[0012] Hereinafter, the case where the crane device is an overhead crane will be described as an example, but it is not limited thereto. The technical idea of the embodiment can be applied to a stacker crane and other cranes as long as there is no contradiction.

[0013] FIG. 2 is a perspective view of a crane device 10 according to an embodiment. The crane device 10 is an overhead crane for transporting an object to be lifted, and is installed in a building such as a factory. The crane device 10 includes a crane body 12, a moving mechanism 14, and a control device 16. The control device 16 is connected to the crane body 12 and the moving mechanism 14 by wire or wirelessly.

[0014] Hereinafter, a certain horizontal direction will be described as the x direction, the horizontal direction orthogonal to the x direction as the y direction, and the direction orthogonal to both as the z direction.

[0015] The moving mechanism 14 is a mechanism for moving the crane body 12. In this example, the moving mechanism 14 moves the crane body 12 in the x-direction and the y-direction. The moving mechanism 14 includes a pair of rails (runways) 20a, 20b, a pair of saddles 22a, 22b, a girder (beam) 24, and a trolley 26.

[0016] The pair of rails 20a, 20b are provided, for example, near the ceiling of a building. The pair of rails 20a, 20b extend in the x-direction, parallel to each other with a predetermined interval in the y-direction. The saddles 22a, 22b are carriages driven by a motor (not shown). The saddles 22a, 22b travel on the rails 20a, 20b in their extending direction (x-direction) based on control signals from the control device 16, respectively.

[0017] The girder 24 has a rectangular frame shape that is long in the y-direction in plan view, although not particularly limited. The girder 24 is spanned across the saddles 22a, 22b. That is, the girder 24 is supported at both ends by the saddles 22a, 22b. The girder 24 moves in the x-direction integrally with the saddles 22a, 22b.

[0018] The trolley 26 is a carriage driven by a motor (not shown) and supports the crane body 12. The trolley 26 has a rectangular frame shape in plan view (when viewed in the z-direction), although not particularly limited. The trolley 26 travels on the girder 24 in its extending direction (y-direction) based on control signals from the control device 16.

[0019] That is, the moving mechanism 14 moves the crane body 12 in the xy-direction by moving the saddles 22a, 22b and thus the girder 24 in the x-direction and moving the trolley 26 in the y-direction.

[0020] The crane body 12 is a wire-driven crane. The crane body 12 employs a parallel wire drive mechanism that realizes the six-degree-of-freedom movement of the object to be controlled (the lifting tool 28) by seven wire drive mechanisms 32. Note that the degree of freedom is not particularly limited, and the (N + 1) wire drive mechanisms may realize the N-degree-of-freedom movement of the object to be controlled.

[0021] The crane body 12 includes a lifting tool 28, seven wires 30, and seven (the same number as the wires 30) wire drive mechanisms 32. Note that the number of the wires 30 and the wire drive mechanisms 32 is not particularly limited.

[0022] The lifting tool 28 includes a support column portion 34, a lower base 36, an upper base 38, and a suspension portion 40. The support column portion 34 is a long member and is supported in a state of being inserted inside the trolley 26 by a plurality of wires 30. The upper base 38 is fixed to the upper end side of the support column portion 34, and the lower base 36 is fixed to the lower end side of the support column portion 34. The lower base 36 and the upper base 38 are not particularly limited, but both are rectangular plate-shaped. The suspension portion 40 is fixed to the lower base 36. The suspension portion 40 may be a hook, a robot hand, or others.

[0023] The support column portion 34 is configured to be stretchable in the longitudinal direction. For example, the support column portion 34 may be composed of a structure that is stretchable in the longitudinal direction and an actuator that stretches and contracts it. Also, for example, the support column portion 34 may be an actuator such as a hydraulic cylinder that is stretchable in the longitudinal direction. In any case, the support column portion 34 stretches and contracts based on a control signal from the control device 16.

[0024] Particularly, when realizing a predetermined operating area, the support column portion 34 is configured to be stretchable such that the length of the lifting tool 28 is shorter than the length of a non-stretchable lifting tool (hereinafter also referred to as a "non-stretchable lifting tool") that realizes the operating area if it is realized by a non-stretchable lifting tool different from the lifting tool 28.

[0025] Note that the length (L max ) at the maximum extension of the support column portion 34, which is the stretchable part, with respect to the length (Lmin ) ratio (L min / L max ) is preferably as small as possible. For example, in the case of a general single-rod cylinder with hydraulic or pneumatic pressure, the ratio is 1 / 2 or less.

[0026] FIGS. 3(a) and 3(b) are side views showing an example of the crane body 12, respectively. In FIGS. 3(a) and 3(b), the display of the suspension part 40 is omitted. In these examples, the support part 34 constitutes a scissor link. In the example of FIG. 3(a), the support part 34 is extended and contracted by applying torque to the root rotation joint of the motor 50 based on a control signal from the control device 16. In the example of FIG. 3(b), the support part 34 is extended and contracted by extending and contracting a cylinder 52 provided across the support part 34 and the upper base 38 based on a control signal from the control device 16. In any case, since the support part 34 constitutes a scissor link, L min / L max can be made relatively small.

[0027] Returning to FIG. 2, the seven wires 30 are, for example, single wires or stranded wires having flexibility such as steel wires. The seven wires 30 are connected to the suspension tool 28, and their connection points are dispersed on the lower end side and the upper end side of the suspension tool 28. That is, a part of the seven wires 30 is connected to the lower end side of the suspension tool 28, and the rest is connected to the upper end side of the suspension tool 28.

[0028] Here, four of the seven wires 30 (hereinafter also referred to as "lower wires 30a") are connected to the lower end side of the suspension tool 28, specifically, to the lower base 36, and the remaining three wires 30 (hereinafter also referred to as "upper wires 30b") are connected to the upper end side of the suspension tool 28, specifically, to the upper base 38. Note that a configuration in which the suspension tool 28 does not include the lower base 36 is also conceivable. In this case, the lower wire 30a may be connected to, for example, the lower end of the support part 34 or to the suspension part 40. Also, a configuration in which the suspension tool 28 does not include the upper base 38 is also conceivable. In this case, the upper wire 30b may be connected to, for example, the upper end of the support part 34.

[0029] The lower wire 30a supports the weight of the object lifted by the suspension tool 28 and the suspension tool 28. Therefore, for safety, it is preferable that the number of the lower wires 30a is larger than the number of the upper wires 30b.

[0030] The upper wire 30b generates a downward force along the longitudinal direction on the support column portion 34 so that the lower wire 30a does not loosen (that is, the tension does not become zero). Thereby, it becomes possible to move the suspension tool 28 at high speed.

[0031] The seven wire drive mechanisms 32 feed out and wind up the wire 30 based on a control signal from the control device 16. The configuration of the wire drive mechanism 32 is not particularly limited. For example, the wire drive mechanism 32 includes a motor and a pulley fixed to the output shaft of the motor, the wire 30 is wound around the pulley, and by rotating the pulley forward and backward by an appropriate angle with the motor, the wire wound around the pulley is fed out or wound up by an appropriate length.

[0032] The seven wire drive mechanisms 32 are arranged within the region A. The region A is a region between the connection point of the upper wire 30b and the suspension tool 28 (that is, the upper base 38) and the connection point of the lower wire 30a and the suspension tool 28 (that is, the lower base 36).

[0033] Specifically, four wire drive mechanisms 32 (hereinafter also referred to as "lower wire drive mechanisms 32a") corresponding to each of the four lower wires 30a (that is, feeding out and winding up) are fixed to the lower surface of the trolley 26, and three wire drive mechanisms 32 (hereinafter also referred to as "upper wire drive mechanisms 32b") corresponding to the three upper wires 30b are fixed to the upper surface of the trolley 26.

[0034] All of the seven wires 30 are linearly and directly stretched from the connection point with the suspension tool 28 to the wire drive mechanism 32. Therefore, the seven wires 30 are stretched only within the region A. In this case, the dimension of the crane body 12 in the Z direction becomes compact.

[0035] Of the seven wires 30, at least one may be stretched via one or more guides for direction conversion (not shown). The guide may be, for example, just a ring or a rotatably supported roller. The guide is preferably arranged within region A. For example, the guide is fixed to the trolley 26.

[0036] It is also possible to arrange the wire drive mechanism 32 outside region A.

[0037] The control device 16 controls the moving mechanism 14 to move the crane body 12 in the x - direction and the y - direction, or controls the delivery amount of each of the seven wire drive mechanisms 32 of the crane body 12 to move the lifting tool 28 in the x - direction, y - direction, z - direction, and their rotational directions, thereby lifting and transporting the object to be lifted. When moving the lifting tool 28, the control device 16 appropriately extends and contracts the support column 34. For example, the control device 16 may contract the support column 34 as the lifting part 40 is moved upward. For example, for each position of the lifting part 40, the delivery amount of each of the seven wire drive mechanisms 32 and the expansion and contraction amount of the support column 34 may be determined.

[0038] FIG. 4 is a diagram for explaining the effects achieved by the embodiment. FIG. 4 is a side view showing the crane body 12. Consider the case of moving the lifting part 40 from the position on the left side to the position on the right side in FIG. 9, that is, the case of moving the lifting part 40 upward. The dashed line in the right - hand figure of FIG. 9 shows the lifting tool 28 if the support column 34 does not contract. As is clear from FIG. 4, by configuring the support column 34 to be extendable and contractible and contracting the support column 34 as the lifting part 40 is moved upward, for example, the upper space required for operation can be reduced compared to the case where this is not done.

[0039] As described above, the present invention has been described based on the embodiments. It is understood by those skilled in the art that these embodiments are examples, and various modifications are possible for the combinations of their respective components and each processing process, and such modifications are also within the scope of the present invention. Hereinafter, such modifications will be described.

[0040] (First Modification Example) FIG. 5 is a perspective view of the crane device 10 according to a modification of the embodiment. FIG. 5 corresponds to FIG. 2. The moving mechanism 14 of this modification does not include the trolley 26, and the wire drive mechanism 32 is supported by the gantry 24. The wire drive mechanism 32 is, for example, a wheeled one driven by a motor, and travels on the gantry 24 based on a control signal from the control device 16. It can also be considered that the wheels of the wire drive mechanism 32 and the motor that drives them constitute the moving mechanism 14 together with the pair of rails 20a, 20b, the pair of saddles 22a, 22b, and the gantry 24. According to this modification, the same operational effects as those of the embodiment can be achieved.

[0041] (Second Modification Example) FIG. 6 is a perspective view of the crane device 10 according to another modification of the embodiment. FIG. 6 corresponds to FIG. 2. In this modification, the moving mechanism 14 includes only the pair of rails 20a, 20b, and does not include the pair of saddles 22a, 22b, the gantry 24, and the trolley 26. The wire drive mechanism 32 is supported by the rails 20a, 20b. The wire drive mechanism 32 is, for example, a wheeled one driven by a motor, and travels on the rails 20a, 20b based on a control signal from the control device 16. It can also be considered that the wheels of the wire drive mechanism 32 and the motor that drives them constitute the moving mechanism 14 together with the pair of rails 20a, 20b. According to this modification, the same operational effects as those of the embodiment can be achieved.

[0042] (Third Modification Example) Although not particularly mentioned in the embodiment, the telescoping of the support column 34 may be used to realize the degree of freedom of movement of the hoist 28 in the N direction. That is, the degree of freedom of movement of the hoist 28 in the N direction may be realized by N wire drive mechanisms and the telescoping support column 34. In this case, one wire drive mechanism 32 can be reduced.

[0043] (Fourth Modification Example) Unlike the embodiment, a configuration in which the crane device 10 does not include the moving mechanism 14 is also conceivable. In this case, the crane body 12 may be supported, for example, by a frame in a building or the like.

[0044] Any combination of the above-described embodiments and modifications is also useful as an embodiment of the present invention. The new embodiments resulting from the combination have the effects of the embodiments and modifications combined.

Description of Reference Numerals

[0045] 10 Crane device, 12 Crane body, 14 Moving mechanism, 16 Control device, 28 Hoisting tool, 30 Wire, 32 Wire drive mechanism.

Claims

1. A lifting tool, A plurality of wires supporting the lifting tool, A plurality of wire driving mechanisms for feeding and winding each of the plurality of wires, and comprising: The connection points between the lifting tool and the plurality of wires are dispersed on the lower end side and the upper end side of the lifting tool, The lifting tool is stretchable between the connection point on the lower end side and the connection point on the upper end side, Among the plurality of wires, the wire connected to the connection point on the lower end side supports the lifting tool, and the wire connected to the connection point on the upper end side generates a downward force on the lifting tool, All of the plurality of wire driving mechanisms are crane devices that feed and wind the wire between the connection point on the lower end side and the connection point on the upper end side.

2. The crane device according to claim 1, wherein when the lifting tool realizes a predetermined operating area, the lifting tool is contractible so as to be shorter than the length of the non-stretchable lifting tool when the non-stretchable lifting tool that cannot be stretched or contracted realizes the operating area.

3. The crane device according to claim 1 or 2, wherein the lifting tool constitutes a scissor link.

4. The crane device according to any one of claims 1 to 3, further comprising a moving mechanism for moving the plurality of wire driving mechanisms.

5. An object to be controlled, A plurality of wires supporting the object to be controlled, A plurality of wire driving mechanisms for feeding and winding each of the plurality of wires, and comprising: The connection points between the object to be controlled and the plurality of wires are dispersed on the lower end side and the upper end side of the object to be controlled, The object to be controlled is stretchable between the connection point on the lower end side and the connection point on the upper end side, Among the plurality of wires, the wire connected to the connection point on the lower end side supports the object to be controlled, and the wire connected to the connection point on the upper end side generates a downward force on the object to be controlled, All of the plurality of wire driving mechanisms are parallel wire driving mechanisms that feed and wind the wire between the connection point on the lower end side and the connection point on the upper end side.

Images