JP2023147583A - Crane device and parallel wire drive mechanism - Google Patents

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

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

Crane devices such as overhead cranes are known. The crane device transports the object by lifting the object with a lifting tool and moving the lifting tool in a horizontal direction. Crane devices are available in various structures, one of which is a crane device that uses a parallel wire drive mechanism.

Patent Document 1 discloses a parallel wire drive mechanism. This parallel wire drive mechanism includes (N+1) wires connected to an object to be controlled and (N+1) wire drive mechanisms that feed or take up the wires, and connects the (N+1) wires and the object to be controlled. The connection points are distributed between the lower end and the upper end of the object to be controlled, thereby realizing movement of the object to be controlled with N degrees of freedom.

Japanese Patent Application Publication No. 7-267575

FIG. 1 is a diagram illustrating problems with a conventional parallel wire drive mechanism as described in Patent Document 1. Connection points between the controlled object 102 and the wires 104 extending from each of a plurality of wire drive mechanisms (not shown) are distributed between a lower end 102a and an upper end 102b of the controlled object 102. A hanging part (not shown), such as a hook or a robot hand, is attached to the lower end 102a of the controlled object 102. This parallel wire drive mechanism requires an upper space S that is substantially the same size as the lower end 102a of the controlled object 102, and thus the operating area R of the hanging section. When a crane device equipped with such a parallel wire drive mechanism is installed in a building such as a factory, a significant amount of space within the building is consumed.

The present invention has been made in view of these circumstances, and one exemplary objective of one aspect of the present invention is to provide a crane device that can reduce the head space required for operation.

In order to solve the above problems, a crane device according to an aspect of the present invention includes a lifting device, a plurality of wires that support the lifting device, and a plurality of wire drives that feed and take up each of the plurality of wires. A mechanism. Connection points between the hanging tool and the plurality of wires are distributed between one end side and the other end side of the hanging section, and the hanging tool is expandable and contractible between the connecting point on one end side and the connecting point on the other end side. be.

Note that arbitrary combinations of the above-mentioned components and mutual substitution of the components and expressions of the present invention among methods, devices, systems, etc. are also effective as aspects of the present invention.

According to the present invention, it is possible to provide a crane device that can reduce the upper space required for operation.

It is a figure explaining the problem of the conventional parallel wire drive mechanism. FIG. 1 is a perspective view of a crane device according to an embodiment. 3(a) and 3(b) are side views showing an example of the crane main body of FIG. 2, respectively. It is a figure explaining the effect which embodiment has. It is a perspective view of the crane device concerning the modification of an embodiment. It is a perspective view of the crane device concerning another modification of an embodiment.

Hereinafter, the same or equivalent components and members shown in each drawing will be given the same reference numerals, and redundant explanations will be omitted as appropriate. Further, the dimensions of members in each drawing are shown enlarged or reduced as appropriate to facilitate understanding. Further, in each drawing, some members that are not important for explaining the embodiments are omitted.

In the following, a case where the crane device is an overhead crane will be described as an example, but the invention is not limited to this, and the technical idea of the embodiment can be applied to a stacker crane and other cranes as long as there is no contradiction.

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

Hereinafter, a certain horizontal direction will be described as an x direction, a horizontal direction perpendicular to the x direction as a y direction, and a direction perpendicular to both as a z direction.

The moving mechanism 14 is a mechanism that moves the crane main 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 24, and a trolley 26.

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

Although not particularly limited, the girder 24 has a rectangular frame shape that is long in the y direction when viewed from above. The girder 24 spans the saddles 22a and 22b. That is, the girder 24 is supported at both ends by the saddles 22a and 22b. The girder 24 moves in the x direction together with the saddles 22a and 22b.

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

In other words, the moving mechanism 14 moves the saddles 22a, 22b and ultimately the girder 24 in the x direction, and moves the trolley 26 in the y direction, thereby moving the crane main body 12 in the x and y directions.

The crane main body 12 is a wire-driven crane. The crane main body 12 employs a parallel wire drive mechanism that realizes the degree of freedom of movement of a controlled object (hanger 28) in six directions by seven wire drive mechanisms 32. Note that the degree of freedom is not particularly limited, and the degree of freedom of movement of the controlled object in the N direction may be realized by (N+1) wire drive mechanisms.

The crane main body 12 includes a hanging device 28, seven wires 30, and seven (same number as the wires 30) wire drive mechanisms 32. Note that the number of wires 30 and wire drive mechanisms 32 is not particularly limited.

The hanging tool 28 includes a support portion 34, a lower base 36, an upper base 38, and a hanging portion 40. The support column 34 is a long member, and is supported by a plurality of wires 30 while being inserted inside the trolley 26 . The upper base 38 is fixed to the upper end side of the column part 34, and the lower base 36 is fixed to the lower end side of the column part 34. The lower base 36 and the upper base 38 are both shaped like rectangular plates, although they are not particularly limited. The hanging portion 40 is fixed to the lower base 36. The hanging part 40 may be a hook, a robot hand, or the like.

The strut portion 34 is configured to be expandable and contractible in the longitudinal direction. For example, the support column 34 may be composed of a longitudinally expandable structure and an actuator that expands and contracts the structure. Further, for example, the strut portion 34 may be an actuator such as a hydraulic cylinder that is extendable and retractable in the longitudinal direction. In any case, the support column 34 expands and contracts based on a control signal from the control device 16.

The support section 34 is particularly useful when realizing a predetermined operating area, and if the operating area is temporarily realized with a non-extendable sling (hereinafter also referred to as a "non-extendable sling") that is different from the sling 28. The hanging tool 28 is configured to be extendable and contractible so that the length of the hanging tool 28 is shorter than the length of the non-extensible hanging tool.

Note that the ratio (L _min /L _max ) of the length at maximum contraction (L _min ) to the length at maximum expansion (L _max ) of the support portion 34, which is an expansion/contraction portion, is better as smaller as possible. For example, in the case of a typical hydraulic or pneumatic single rod cylinder, the ratio is 1/2 or less.

FIGS. 3A and 3B are side views showing an example of the crane main body 12, respectively. In FIGS. 3A and 3B, the hanging portion 40 is not shown. In these examples, the struts 34 constitute scissor links. In the example shown in FIG. 3A, the motor 50 applies torque to the rotary joint at the base based on a control signal from the control device 16, thereby expanding and contracting the support column 34. In the example of FIG. 3(b), the cylinder 52 provided across the column 34 and the upper base 38 is expanded and contracted based on a control signal from the control device 16, so that the column 34 is expanded and contracted. In any case, L _min /L _max can be made relatively small by having the support section 34 constitute a scissor link.

Returning to FIG. 2, the seven wires 30 are, for example, flexible single wires or twisted wires such as steel wires. The seven wires 30 are connected to the hanging tool 28, and their connection points are distributed between the lower end side and the upper end side of the hanging tool 28. That is, some of the seven wires 30 are connected to the lower end side of the hanging tool 28, and the rest are connected to the upper end side of the hanging tool 28.

Here, four wires 30 (hereinafter also referred to as "lower wires 30a") out of the seven wires 30 are connected to the lower end side of the hanging tool 28, specifically, to the lower base 36, and the remaining three A main wire 30 (hereinafter also referred to as "upper wire 30b") is connected to the upper end side of the hanging tool 28, specifically, to the upper base 38. Note that a configuration in which the hanging tool 28 does not include the lower base 36 is also considered, and in this case, the lower wire 30a may be connected to, for example, the lower end of the support section 34, or may be connected to the hanging section 40. Further, a configuration in which the hanging tool 28 does not include the upper base 38 is also considered, and in this case, the upper wire 30b may be connected to, for example, the upper end of the support portion 34.

The lower wire 30a supports the weight of the hanger 28 and the object it is lifting. Therefore, for safety, it is preferable that the number of lower wires 30a is greater than the number of upper wires 30b.

The upper wire 30b generates a downward force on the column 34 in the longitudinal direction so that the lower wire 30a does not loosen (that is, the tension does not become zero). This makes it possible to move the hanging tool 28 at high speed.

The seven wire drive mechanisms 32 feed and wind up the wire 30 based on control signals 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 the wire 30 is wound around the pulley by rotating the pulley forward and backward by an appropriate angle with the motor. Feed out or wind up the wire to the appropriate length.

Seven wire drive mechanisms 32 are arranged within area A. Region A is an area between the connection point between the upper wire 30b and the hanging tool 28 (ie, the upper base 38) and the connection point between the lower wire 30a and the hanging tool 28 (ie, the lower base 36).

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, feed and wind up) are fixed to the lower surface of the trolley 26. , 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.

All of the seven wires 30 are stretched directly in a straight line from the connection point with the hanging tool 28 to the wire drive mechanism 32. Therefore, the seven wires 30 are stretched only within area A. In this case, the size of the crane body 12 in the Z direction becomes compact.

Note that at least one of the seven wires 30 may be stretched via one or more direction change guides (not shown). The guide may be, for example, a simple ring or a rotatably supported roller. The guide is preferably located within area A. For example, the guide is fixed to the trolley 26.

Note that it is also possible to arrange the wire drive mechanism 32 outside the area A.

The control device 16 controls the movement mechanism 14 to move the crane body 12 in the x direction and the y direction, and controls the feed amount of each of the seven wire drive mechanisms 32 of the crane body 12 to move the lifting device 28 in the x direction. The object to be lifted is lifted and conveyed by moving it in the y-direction, y-direction, z-direction, and their rotational directions. When the control device 16 moves the hanging tool 28, it expands and contracts the support section 34 as appropriate. For example, the control device 16 may contract the support portion 34 as the hanging portion 40 is moved upward. For example, the amount of feed of each of the seven wire drive mechanisms 32 and the amount of expansion and contraction of the support portion 34 may be determined for each position of the hanging portion 40.

FIG. 4 is a diagram illustrating the effects of the embodiment. FIG. 4 is a side view showing the crane main body 12. Consider a case where the hanging part 40 is moved from a position on the left side to a position on the right side in FIG. 9, that is, a case where the hanging part 40 is moved upward. The broken line in the right view of FIG. 9 shows the suspension 28 if the support 34 does not contract. As is clear from FIG. 4, by configuring the support section 34 to be expandable and contractible, and contracting the support section 34 as the hanging section 40 is moved upward, for example, the support section 34 can be expanded and contracted to meet the requirements for operation compared to the case where this is not the case. The upper space can be reduced.

The present invention has been described above based on the embodiments. Those skilled in the art will understand that this embodiment is merely an example, and that various modifications can be made to the combinations of these components and processing processes, and that such modifications are also within the scope of the present invention. be. Hereinafter, such modified examples will be explained.

(First modification)
FIG. 5 is a perspective view of a crane device 10 according to a modification of the embodiment. FIG. 5 corresponds to FIG. The moving mechanism 14 of this modification does not include the trolley 26, and the wire drive mechanism 32 is supported by the girder 24. The wire drive mechanism 32 has wheels driven by a motor, for example, and moves on the girder 24 by itself based on a control signal from the control device 16. Note that the wheels of the wire drive mechanism 32 and the motor that drives them can also be considered to constitute the moving mechanism 14 together with the pair of rails 20a, 20b, the pair of saddles 22a, 22b, and the girder 24. According to this modification, the same effects as the embodiment can be achieved.

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

(Third modification)
Although not specifically mentioned in the embodiment, expansion and contraction of the support column 34 may be used to realize the degree of freedom of movement of the hanger 28 in the N direction. In other words, the freedom of movement of the hanger 28 in the N direction may be realized by the N wire drive mechanisms and the expandable support section 34. In this case, the number of wire drive mechanisms 32 can be reduced by one.

(Fourth modification)
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 main body 12 may be supported by, for example, a frame within a building.

Any combination of the embodiments and variations described above are also useful as embodiments of the present invention. A new embodiment resulting from a combination has the effects of each of the combined embodiments and modifications.

10 Crane device, 12 Crane main body, 14 Movement mechanism, 16 Control device, 28 Hanging tool, 30 Wire, 32 Wire drive mechanism.

Claims (5)

A sling and
a plurality of wires supporting the hanging device;
A plurality of wire drive mechanisms that feed and wind up each of the plurality of wires,
Connection points between the hanging tool and the plurality of wires are distributed on a lower end side and an upper end side of the hanging part,
In the crane device, the hanging tool is extendable and retractable between a connecting point on the lower end side and a connecting point on the upper end side. The hanging device is capable of contracting so that when realizing a predetermined working area, the length of the hanging device is shorter than the length of the non-extensible hanging device when the working area is realized by a non-stretchable hanging device. The crane device according to item 1. The crane device according to claim 1 or 2, wherein the hanging device constitutes a scissor link. The crane device according to any one of claims 1 to 3, further comprising a moving mechanism that moves the plurality of wire drive mechanisms. A controlled object;
a plurality of wires supporting the controlled object;
A plurality of wire drive mechanisms that feed and wind up each of the plurality of wires,
Connection points between the controlled object and the plurality of wires are distributed on a lower end side and an upper end side of the controlled object,
The object to be controlled is a parallel wire drive mechanism that is expandable and retractable between a connection location on the lower end side and a connection location on the upper end side.

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