JP4307805B2 - Parallel link device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a parallel link device including a fixed node as a reference, a working node whose position is displaced, and a pair of link nodes connecting the fixed node and the working node, and the fixed node and the working node are parallel to each other.
[0002]
[Prior art]
In many cases, it is desired to maintain the posture of the movement part (the tip of the robot arm, the gripping part of the wafer, etc.) such as transmission of input / output of the steering operation to the robot arm and delivery of a wafer between devices in semiconductor manufacturing. When the motion of the motion part is only in a single plane (in the case of one degree of freedom), the posture maintenance of the motion part can be realized relatively easily by using a parallel link. However, when the motion of the motion part is in a plurality of planes, that is, with multiple degrees of freedom, the parallel links cannot be used as they are, and how to combine the parallel links corresponding to the number of degrees of freedom becomes a problem.
[0003]
For example, Japanese Patent Laid-Open No. 2000-284849 “steering device” forms a set of parallel links in planes orthogonal to each other, and one of the parallel links has one tip with respect to the other tip. The link mechanism which supported each support end so that it can rotate within the plane which belongs to is shown. This is a configuration in which a rotation shaft having another rotation surface is integrally provided on a rotation shaft itself of a certain parallel link, and a parallel link having one degree of freedom is combined to have two degrees of freedom as a whole.
[0004]
[Problems to be solved by the invention]
The above Japanese Patent Laid-Open No. 2000-284849 is a control device. The purpose is to provide a control stick at the action node and capture the movement of this control stick with a sensor, so it realizes accurate two-degree-of-freedom movement using parallel links. do it. However, assuming that the action node is loaded, the configuration in which a plurality of rotating surfaces are set on the rotating shaft itself may be insufficient in strength, and each parallel link moves smoothly. There is no concern. Therefore, in configuring a parallel link device having two degrees of freedom as a whole, combinations of parallel links for realizing necessary and sufficient structural strength and stable operation were examined.
[0005]
[Means for Solving the Problems]
As a result of the study, what was developed is a parallel link device comprising a fixed node as a reference, a working node whose position is displaced, and a pair of link nodes connecting the fixed node and the working node, and the fixed node and the working node are parallel. The upper and lower vertical rotation shafts (first rotation shaft) and the lower vertical rotation shaft (first rotation shaft) of the upper and lower stages are horizontally projected on the fixed and working nodes, respectively, so that the upper and lower vertical rotation shafts of the fixed node are projected. The upper fixed node side link node is connected to the lower vertical rotation axis of the fixed node, the lower fixed node side link node with the supporting arm extended to the left and right, and the upper fixed node side link node to the upper vertical rotation axis of the working node. The lower fixed joint side link node with the support arm extended to the left and right is pivotally attached to the lower vertical rotation axis of the working node, and the upper fixed node side link node and the lower fixed node side link node on the same fixed node side are respectively attached. Upper action node side link and lower action nodes on the same action node side The link nodes are equal in length, and the upper fixed node side link node and the upper action node side link node project the upper horizontal rotation shaft (second rotation shaft) upward from the end, and the lower fixed node side link node and The lower actuating node side link node has two lower horizontal pivoting shafts (second pivoting shafts) projecting downward from each support arm end, and the upper fixed node side link node and upper actuating node side link node upper stage. The upper intermediate link node is installed in a pivoted state over the horizontal rotation axis, and the lower intermediate link node is installed in a fixed state over the lower horizontal rotation shafts of the lower fixed node side link node and the lower action node side link node. This is a parallel link device having a triangular cross-sectional arrangement in which the upper intermediate link node is the apex and two lower intermediate link nodes are arranged at the corners of both ends of the base .
[0006]
The parallel link device is provided with separate first rotation shafts and second rotation shafts in the link nodes connecting the fixed nodes and the action nodes, and realizes two degrees of freedom according to each rotation shaft. Since each rotation shaft is only responsible for rotation within a single plane, there is no risk of strength reduction on the rotation shaft, and smooth movement of the parallel link is ensured. Rotating surfaces each rotational axis is formed may be identical, to ensure the movement of clause action in a wide range, the rotary shaft first rotation axis vertical, the second rotation axis horizontal pivot axis A parallel link device is preferable.
[0007]
Here, in the parallel link device having two degrees of freedom, the range of movement of the action node is wide, and the load applied to the link node changes in size and direction, so there is a concern that the link node may be twisted. Therefore, the link node is connected to the fixed node and the action node so that there is at least one link node whose positional relationship does not overlap with the other link nodes when viewed from the normal direction of the first rotation surface and the second rotation surface. The parallel link device. When there are two link nodes, the first rotation shaft and the second rotation shaft may be provided so that the first rotation surface and the second rotation surface are different from the surface where the link nodes are arranged.
[0008]
As for the positional relationship of the link node, the link node has three or more link nodes, and the link node and the link that do not overlap with each other when viewed from the normal direction of the first rotation surface and the second rotation surface. It is preferable that each node has one or more nodes. For example, one upper link and two lower intermediate link nodes are arranged in the same horizontal plane in the upper row, and the lower middle corresponding to the corners on both sides of the base of the isosceles triangle with the upper intermediate link node at the apex. Assign a link clause. If more intermediate link nodes are assigned to the lower stage where the load is applied, the structural strength of the parallel link device can be increased.
[0009]
Specific examples of construction of the parallel link devices, there are a plurality of horizontal rotary shaft projecting upward or downward from the respective solid Teifushi side link section and the action section side link section, each fixed link side link section and the action section side link there is a configuration in which a plurality bridging the intermediate link clause in each section. To describe in this configuration, it is provided a support arm extending horizontally on the fixed section side link section and the action section side link section, thus providing a shaft plurality of horizontal once for the support arm.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 is a perspective view of an example of a parallel link device according to the present invention as viewed from the fixed joint 1 side, FIG. 2 is a plan view, FIG. 3 is a side view, and FIG. 4 is a view when the working joint 2 is displaced left and right. 1 is a perspective view corresponding to FIG. 2, FIG. 5 is a plan view corresponding to FIG. 2 when the working node 2 is displaced left and right, FIG. 6 is a side view corresponding to FIG. 3 when the working node 2 is displaced left and right, and FIG. FIG. 8 is a perspective view corresponding to FIG. 2 when the working node 2 is displaced up and down, and FIG. 9 is a plan view corresponding to FIG. 2 when the working node 2 is displaced up and down. FIG. 4 is a side view corresponding to FIG. 3.
[0011]
As shown in FIG. 1, the parallel link device of this example has two upper and lower stages from each of the flat fixed node 1 and action node 2 to the right (right in FIG. 1, lower in FIG. 2, or in front of FIG. 3). Two vertical rotation shafts (first rotation shafts) 3 and 4 that are separated from each other are projected. A short bar-like upper fixed node side link node 5 or upper action node side link node 6 is pivotally attached to the upper vertical rotation shafts 3 and 3 as a link node division unit. The lower vertical pivot shafts 4 and 4 have a lower fixed node side link node 8 or a lower action node side link node 9 in which the support arms 7 and 7 are extended from a short bar to the left and right as a link node division unit. I wear it. Here, the upper fixed node side link node 5 and the lower fixed node side link node 8 on the same fixed node side are of equal length, and the upper action node side link node 6 and the lower operation node side link node on the same action node side. 9 is isometric.
[0012]
The upper fixed node side link node 5 and the upper action node side link node 6 each have one upper horizontal rotation shaft (second rotation shaft) 10, 10 protruding upward from the end portion. On the other hand, the lower fixed joint side link node 8 and the lower action node side link node 9 have a total of two lower horizontal rotation shafts (second rotation shafts) 11, 11 at the ends of the support arms 7, 7. Protrusively toward. Then, the upper intermediate link node 12 is installed on the upper horizontal rotating shafts 10 and 10 of the upper fixed node side link node 5 and the upper operation node side link node 6 in the axially attached state. Lower intermediate link nodes 13 and 13 are installed in a state of axial attachment over the lower horizontal rotation shafts 11 and 11 of the node side link node 9. As is apparent from FIGS. 1, 2 and 3, the upper intermediate link node 12 is the apex, and the two lower intermediate link nodes 13, 13 are arranged in a triangular cross section with the corners at the bottom edges. Yes.
[0013]
The parallel link device of the present example fixes the position of the fixed node 1 and can displace the working node 2 up and down and left and right while maintaining the posture of the fixed node 1. Can be used as an input unit or an output unit that is displaced. For example, when the action node 2 is displaced left and right, as shown in FIGS. 4, 5 and 6, the upper and lower stage fixed node side link nodes 5 and 8 and the upper and lower stage action node side link nodes 6 and 9 are provided. According to the upper and lower horizontal rotation shafts 10 and 11, only the upper and lower intermediate link nodes 12 and 13 swing left and right, and the upper and lower vertical rotation shafts 3 and 4 provided on the fixed node 1 and the action node 2 do not work (side surface). Fig. 3 and Fig. 6 control).
[0014]
On the other hand, when the working node 2 is displaced up and down, as shown in FIGS. 7, 8, and 9, the upper and lower vertical rotation shafts 3 and 4 provided on the fixed node 1 and the working node 2 are moved upward. The lower fixed node side link nodes 5 and 8, the upper and lower intermediate link nodes 12 and 13, and the upper and lower action node side link nodes 6 and 9 swing up and down integrally, and the upper and lower fixed node side link nodes 5 and 8 and upper The upper and lower horizontal rotation shafts 10 and 11 provided on the lower action node side link nodes 6 and 9 do not work (refer to FIGS. 2 and 7 which are plan views).
[0015]
The left and right displacements (FIGS. 4, 5, and 6) and the vertical displacements (FIGS. 7, 8, and 9) of the action node 2 have different turning radii. Thus, the action node 2 maintains the posture. Also, as shown in this example, there are two lower intermediate link sections 13 and 13 and each lower intermediate link section 13 and 13 is arranged in a triangular cross-sectional relationship with respect to the upper intermediate link section 12. There is no twisting of each of the intermediate link nodes 12 and 13 that prevents the posture of the node 2 from being maintained, and stable operation can be achieved.
[0016]
【The invention's effect】
According to the present invention, it is possible to provide a parallel link device that realizes two degrees of freedom while maintaining the posture of the action node. As is clear from the above example, the fixed node and the working node remain the same as the conventional basic parallel link. Therefore, by simply applying the parallel link device of the present invention instead of the parallel link in the existing device, the fixed node can be used. The degree of freedom of the action node for can be increased. This means that the installation space can be reduced. For example, the input / output of steering operation to the robot arm and the transfer of power from input to output, such as wafer transfer between devices in semiconductor manufacturing. This has the effect of facilitating the application of the present invention when it is desired to maintain the posture of the part.
[Brief description of the drawings]
FIG. 1 is a perspective view of an example of a vertical parallel link device viewed from a fixed node side.
FIG. 2 is a plan view of a vertical parallel link device.
FIG. 3 is a side view of the vertical parallel link device.
FIG. 4 is a perspective view corresponding to FIG. 1 when the working node is displaced left and right.
FIG. 5 is a plan view corresponding to FIG. 2 when the working node is displaced left and right.
6 is a side view corresponding to FIG. 3 when the action node is displaced left and right.
FIG. 7 is a perspective view corresponding to FIG. 1 when the working node is displaced up and down.
FIG. 8 is a plan view corresponding to FIG. 2 when the working node is displaced up and down.
9 is a side view corresponding to FIG. 3 when the working node is displaced up and down.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fixed node 2 Action node 3 Upper stage vertical rotation axis 4 Lower stage vertical rotation axis 5 Upper stage fixed node side link node 6 Upper stage action node side link node 7 Support arm 8 Lower stage fixed node side link node 9 Lower stage action node side link node
10 Upper horizontal rotation axis
11 Lower horizontal rotation axis
12 Upper middle link section
13 Lower middle link section

Claims (1)

In a parallel link device composed of a reference fixed node, a positionally displaced action node, and a pair of link nodes connecting the fixed node and the action node, the fixed node and the action node are parallel to each other. The upper vertical rotation axis and lower vertical rotation axis of the stage protrude horizontally, the upper fixed link side link node on the upper vertical rotation axis of the fixed node, and the left and right support arms on the lower vertical rotation axis of the fixed node The lower fixed-node-side link node with the extension of the lower-stage fixed-node-side link, the upper-stage fixed-node-side link node on the upper-stage vertical rotation shaft of the working node, and the lower-stage fixed-node-side link with the support arm extended to the left and right The upper fixed node side link node and the lower fixed node side link node on the same fixed node side are of equal length, the upper action node side link node and the lower action node side link node on the same action node side. Is the same length, the upper fixed joint side link node and the upper stage action The side link node protrudes the upper horizontal rotation shaft upward from the end, and the lower fixed node side link node and the lower action node side link node lower the total two lower horizontal rotation shafts from each support arm end. The upper intermediate link node is installed on the upper horizontal rotation axis of the upper fixed link and upper action link and the upper fixed link and lower action link. The lower intermediate link node is installed in a pivoted state across each lower horizontal rotation shaft, and the upper intermediate link node is the apex, and the two lower intermediate link nodes are arranged at the corners at the bottom edges, and A parallel link device characterized by that.

Images