TW201323143A - Compliance device - Google Patents

Abstract

A compliance device including a first body, a plurality of first stretchable elements, a second body, a plurality of second stretchable elements and a chuck is provided. The second body is connected to the first body via the first stretchable elements and suitable for moving back and forth relative to the first body along a first direction. The second body has a chamber and an opening communicated to the chamber. The chuck has a moving part, a connecting part and a clipping part. The moving part is disposed in the chamber via the second stretchable elements. The moving part is suitable for moving on a first plane via the second stretchable elements. The first direction is perpendicular to the first plane. The connecting part passes through the opening and connects the moving part and the clipping part. The clipping part is used for clipping a workpiece.

Description

Compliant device

This invention relates to a device and, more particularly, to a compliance device.

The development of the machine tool is fast and the technology is continuously improved, which can replace the manual assembly engineering. In order to avoid collisions and damage between assembly workpieces caused by positioning errors, remote center compliance devices are often used to achieve the above objectives. A distal center compliant device typically has an upper and lower parallel structure, the upper parallel structure is used to connect with an assembly device such as a robotic arm, and the lower parallel structure is used to connect to the collet. The same three or more elastomers will be placed between the upper and lower parallel structures, inclined and symmetrical to the central axis of the distal center compliant device. The axis of the elastomer will lie at one point, the so-called compliant center, which just falls to the end of the workpiece clamped by the collet. When there is a position or azimuth error between the workpiece and the socket, the elastic body will flex and deform, so that the object can be smoothly inserted into the socket. However, such a distal center compliant device must adjust the azimuth of the elastomer for workpieces of different lengths, which is not convenient to use.

The present invention provides a compliant device that solves the problem of having to adjust the device when the length of the workpiece is different.

The compliant device of the present invention includes a first structural body, a plurality of first telescopic members, a second structural body, a plurality of second telescopic members, and a collet. The first structure is for fixing to a mobile device. The second structural body is coupled to the first structural body via the first telescopic member and adapted to reciprocate in a first direction relative to the first structural body. The second structure has a cavity and an opening communicating with the chamber. The collet has a moving portion, a connecting portion and a clamping portion. The moving portion is disposed in the chamber via the second telescopic member. The moving portion is adapted to move on a first plane by the second telescopic member. The first direction is perpendicular to the first plane. The connecting portion connects the moving portion and the nip portion through the opening. The clamping portion is for holding a workpiece.

In an embodiment of the invention, each of the first telescopic members includes a telescopic rod and a spring. Both ends of the telescopic rod are respectively connected to the first structure body and the second structure body. The spring sleeve is sleeved on the telescopic rod, and the two ends of the spring respectively abut the first structure body and the second structure body.

In an embodiment of the invention, the moving portion has a plurality of blind holes. Each of the second telescopic members includes a rod and a spring. One end of the rod is fixed to the chamber wall of the chamber, and the other end of the rod is located inside the spring. The spring is placed over the rod. The two ends of the spring respectively abut against the cavity wall of the chamber and the bottom of the corresponding blind hole. In addition, the other end of the rod is located outside the corresponding blind hole. Alternatively, the other end of the rod is located in the corresponding blind hole. Or alternatively, the other end of the rod abuts against the bottom of the corresponding blind hole. Additionally, the compliant device can further include a plurality of displacement sensors disposed at the other end of the rod and adapted to be electrically connected to the mobile device. The displacement sensor is configured to trigger the mobile device to stop moving the first structure when sensing that the distance from the bottom of the blind hole is less than a threshold.

In an embodiment of the invention, the compliant device further includes a plurality of displacement sensors disposed within the chamber and adapted to be electrically connected to the mobile device. The displacement sensor is configured to trigger the mobile device to stop moving the first structure when sensing that the distance from the moving portion is less than a threshold. In addition, each displacement sensor and the corresponding second telescopic member are located, for example, on opposite sides of the moving portion.

Based on the above, in the compliant device of the present invention, the two types of telescopic members allow the collet to have a multi-directional elastic change space, which reduces the chance of damage due to collision of the workpiece.

The above described features and advantages of the present invention will be more apparent from the following description.

1 to 3 are respectively an external view, a vertical sectional view and a horizontal sectional view of a compliant device according to an embodiment of the present invention. Referring to FIG. 1 and FIG. 2 , the compliant device 100 of the present embodiment includes a first structural body 110 , a plurality of first telescopic members 120 , a second structural body 130 , a plurality of second telescopic members 140 , and a collet 150 . . The first structure body 110 is used for fixing to a mobile device (not shown). The first structure 110 of the present embodiment is adapted to be fixed to a robot arm (not shown), but the first structure of other embodiments may also be fixed to other kinds of mobile devices. The mobile device is used to move the first structure 110 to drive the entire compliant device 100. The second structure body 130 is connected to the first structure body 110 via the first extension member 120 , that is, the first extension tube 120 is connected between the first structure body 110 and the second structure body 130 . Because of the action of the first telescopic member 120, the second structural body 130 can reciprocate relative to the first structural body 110 in a first direction D10. In this embodiment, the number of the first telescopic members 120 is three, and is substantially parallel to the first direction D10, for example, the direction of the vertical ground.

The second structure 130 has a chamber 132 and an opening 134 communicating with the chamber 132. The collet 150 has a moving portion 152, a connecting portion 154 and a clamping portion 156. The moving portion 152 is disposed in the chamber 132 via the second telescopic member 140, that is, the second telescopic member 140 is coupled between the moving portion 152 and the chamber wall of the chamber 132. Because of the action of the second telescopic member 140, the moving portion 152 can move on a first plane P10. The first direction D10 is perpendicular to the first plane P10, for example parallel to the plane of the ground. In other words, the moving direction of the moving portion 152 with respect to the second structure body 130 is substantially perpendicular to the moving direction of the first structure body 110 with respect to the second structure body 130. In addition, a gap X may be left between the moving portion 152 and the top wall of the chamber 132, so that the moving portion 152 has a slight inversion and a vertical movement margin in the chamber 132. Thereby, the moving part 152 can perform three-dimensional movement with respect to the mobile device. The connecting portion 154 passes through the opening 134 to connect the moving portion 152 and the clamping portion 156, and the moving portion 152 is confined in the chamber 132 and cannot pass through the opening 134. The projected size of the opening 134 of the present embodiment on the first plane P10 is slightly larger than the projected size of the connecting portion 154 at the first plane P10 to avoid restricting the movement of the moving portion 152 on the first plane P10. The clamping portion 156 is for holding a workpiece (not shown).

In the compliant device 100 of the present embodiment, the first telescopic member 120 and the second telescopic member 140 together provide a degree of freedom of movement in a three-dimensional space. Therefore, when the mobile device moves the compliant device 100 to drive the workpiece for alignment and assembly, if the workpiece collides with other components due to the alignment error, the force of the collision can be greatly reduced to avoid damage.

Each of the first telescopic members 120 of the embodiment includes a telescopic rod 122 and a spring 124. Both ends of the telescopic rod 122 are connected to the first structure body 110 and the second structure body 130, respectively. The spring 124 is sleeved on the telescopic rod 122, and the two ends of the spring 124 respectively abut the first structural body 110 and the second structural body 130. The telescopic rod 122 is used to limit the direction of relative movement between the first structural body 110 and the second structural body 130, and the spring 124 is used to connect the first structural body 110 and the second structural body 130 after relative movement occurs. The distance returns to the original state. The moving portion 152 of this embodiment has a plurality of blind holes 152a. Each of the second telescopic members 140 includes a rod 142 and a spring 144. One end of the rod 142 is fixed to the wall of the chamber 132. The spring 144 is placed over the rod 142 such that the other end of the rod 142 is located within the spring 144. The two ends of the spring 144 respectively abut against the cavity wall of the chamber 132 and the bottom of the corresponding blind hole 152a to provide the freedom of movement of the moving portion 152 on the first plane P10 and the restoring force to return to the initial position.

Referring to FIG. 2 and FIG. 3 , the compliant device 100 of the present embodiment further includes a plurality of displacement sensors 160 disposed in the cavity 132 and adapted to be electrically connected to the mobile device. The displacement sensor 160 is configured to trigger the mobile device to stop moving the first structure 110 when the distance between the displacement sensor 160 and the moving portion 152 is sensed to be less than a threshold. In an embodiment, the displacement sensor 160 is a non-contact proximity switch. With this design, the movement of the mobile device can be stopped before the workpiece collides with other objects and the displacement of the collet 150 is excessively large to avoid damage to the workpiece, the compliant device 100 or the mobile device. In the present embodiment, the moving portion 152 is exemplified by a disk shape. In the initial position, the axial extension lines of the three second telescopic members 140 all pass through the axis of the moving portion 152 with an angle of 120 degrees with each other. Each displacement sensor 160 and the corresponding second telescopic member 140 are located on opposite sides of the moving portion 152. Each of the displacement sensors 160 of the present embodiment is located on an extension line of the axis of the corresponding second telescopic member 140. The displacement sensor 160 and the mobile device can transmit signals by wire, or wirelessly.

In Figure 3, the other end of the rod 142 is located outside of the corresponding blind hole 152a. In the embodiment of Figure 4, the other end of the rod 242 is near the bottom of the corresponding blind hole 152a and may partially resist the bottom of the blind hole 152a in some cases. In the embodiment of Figure 5, the other end of the rod 342 is located in the middle of the corresponding blind hole 152a without approaching the bottom of the blind hole 152a. The position of the rod of the second telescopic member in each embodiment is based on the principle that the position of the moving portion can be appropriately limited, and is not limited. In addition, the displacement sensor 360 of the compliant device 300 of FIG. 5 is disposed at the other end of the rod 342. When it is sensed that the distance from the bottom of the blind hole 152a is less than a critical value, the displacement sensor 360 is used to trigger the mobile device to stop moving the first structure (not shown) of the compliant device 300.

In summary, in the compliant device of the present invention, two types of telescopic members having different telescopic directions are used to provide a multi-directional movement degree of movement of the collet, thereby reducing the collision of the workpiece with other components, resulting in the workpiece, the compliant device or the movement. The chance of damage to the device.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100. . . Compliant device

110. . . First structure

120. . . First telescopic piece

122. . . Telescopic rod

124, 144. . . spring

130. . . Second structure

132. . . Chamber

134. . . Opening

140. . . Second telescopic piece

142, 242, 342. . . Lever

150. . . Chuck

152. . . Mobile department

152a. . . Blind hole

154. . . Connection

156. . . Grip

160, 360. . . Displacement sensor

D10. . . First direction

P10. . . First plane

X. . . gap

1 to 3 are respectively an external view, a vertical sectional view and a horizontal sectional view of a compliant device according to an embodiment of the present invention.

4 and 5 are horizontal cross-sectional views of a compliant device in accordance with two further embodiments of the present invention, respectively.

100. . . Compliant device

110. . . First structure

120. . . First telescopic piece

122. . . Telescopic rod

124, 144. . . spring

130. . . Second structure

132. . . Chamber

134. . . Opening

140. . . Second telescopic piece

142. . . Lever

150. . . Chuck

152. . . Mobile department

152a. . . Blind hole

154. . . Connection

156. . . Grip

160. . . Displacement sensor

D10. . . First direction

P10. . . First plane

Claims (11)

A compliant device comprising: a first structure for fixing to a mobile device; a plurality of first telescopic members; and a second structure coupled to the first structure via the first telescopic members Reciprocating relative to the first structure body in a first direction, the second structure body has a chamber and an opening communicating with the chamber; a plurality of second telescopic members; and a collet having a moving portion and a a connecting portion and a clamping portion, wherein the moving portion is disposed in the chamber via the second telescopic members, the moving portion is adapted to be moved on a first plane by the second telescopic members, the first direction The first plane is perpendicular to the connecting portion, and the connecting portion is connected to the moving portion and the clamping portion for clamping a workpiece. The compliant device of claim 1, wherein each of the first telescopic members comprises a telescopic rod and a spring, and the two ends of the telescopic rod are respectively connected to the first structural body and the second structural body, the spring The telescopic rod is sleeved, and the two ends of the spring respectively abut the first structure body and the second structure body. The compliant device of claim 1, wherein the moving portion has a plurality of blind holes, each of the second telescopic members comprising a rod and a spring, one end of the rod being fixed to the cavity wall of the chamber The other end of the rod is located in the spring, and the spring is sleeved on the rod. The two ends of the spring respectively abut against the cavity wall of the chamber and the bottom of the corresponding blind hole. The compliant device of claim 3, wherein the other end of the member is located outside the corresponding blind hole. The compliant device of claim 3, wherein the other end of the rod is located in the corresponding blind hole. The compliant device of claim 3, wherein the other end of the member is adjacent to a bottom of the corresponding blind hole. The compliant device of claim 3, further comprising a plurality of displacement sensors disposed at the other end of the rods and adapted to be electrically connected to the mobile device, wherein the displacement sensors are used to Detecting that the distance from the bottom of the blind hole is less than a threshold value triggers the mobile device to stop moving the first structure. The compliant device of claim 1, further comprising a plurality of displacement sensors disposed in the chamber and adapted to be electrically connected to the mobile device, wherein the displacement sensors are used to sense and When the distance of the moving portion is less than a threshold, the mobile device is triggered to stop moving the first structure. The compliant device of claim 8, wherein each of the displacement sensors and the corresponding second telescopic member are located on opposite sides of the moving portion. The compliant device of claim 1, wherein the moving portion has a gap with the top wall of the chamber for providing a margin for the vertical flipping and moving up and down of the moving portion in the chamber. . The compliant device of claim 1, wherein the projected size of the opening in the first plane is slightly larger than the projected size of the connecting portion in the first plane.