JP2011121162A - Robot finger unit with gripping function - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a robot finger unit that achieves a reduction in the entire volume of a robot hand having a gripping function, and has a high degree of freedom of finger operation and high gripping force. <P>SOLUTION: The robot finger unit includes: a base; a drive mechanism fixed to the base and having a rotary shaft; a first member installed on the base so as to be rotationally movable via a parallel axle, whose one-end side is installed in parallel with the rotary shaft, while using the parallel axle as a rotating shaft; a second member connected with the first member via a vertical axle installed vertically to the rotary shaft on the other-end side of the first member so as to be rotationally movable while using the vertical axle as a rotating shaft; and a pulley rotatably installed in the vertical axle while using the vertical axle as a rotating shaft; and a drive cable. The drive cable includes one end wound around and fixed to the rotary shaft, the other end fixed to the second member, and an intermediate part wound around the pulley. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a robot finger unit having a gripping operation function, and more particularly to a robot finger unit having a high degree of freedom of finger operation and a high gripping force.

  A conventional robot hand having a gripping operation function has a complicated mechanism, and the fingers of the robot hand are usually designed for a specific purpose. For this reason, in order to grip a different object, the fingers of the robot hand are exchanged, and it is very inconvenient at the actual use site. Further, in order to increase the degree of freedom of finger operation and move the fingers in various directions, the number of motors that drive the fingers must be increased. However, as the number of motors increases, the volume and mass of the entire robot hand increases. On the other hand, if the number of motors to be arranged is reduced in order to reduce the volume and mass of the robot hand, the degree of freedom of finger operation is also reduced. Furthermore, when a small motor is selected, if the driving ability is too small, the gripping force of the fingers is insufficient. Therefore, in the design of the robot hand, the greatest goal was to increase the degree of freedom of finger movement and the gripping force while keeping the volume small.

JP 2007-69286 A JP 2009-184030 A

  An object of the present invention is to provide a robot finger unit in which the entire volume of a robot hand having a gripping operation function is small, and the degree of freedom of finger operation and the gripping force are high.

Robot finger unit according to the present invention: The robot finger unit according to the present invention is a robot finger unit having a gripping operation function, and includes a base, a drive mechanism that is fixed to the base, and includes a rotation shaft, and a rotation shaft on one end side. Via a parallel axle installed in parallel with the first member installed on the base so as to be capable of rotational movement with the parallel axle as a rotation axis, and on the other end side of the first member via a vertical axle installed perpendicular to the rotation axis, A second member connected to the first member so as to be rotatable about a vertical axle as a rotation axis; a pulley installed on the vertical axle so as to be rotatable about the vertical axle as a rotation axis; and a drive cable. One end portion wound and fixed, the other end portion fixed to the second member, and an intermediate portion wound around the pulley are provided.

  The robot finger unit according to the present invention includes n intermediate members connected via n + 1 (where n is an integer of 1 or more) vertical axles between the first member and the second member. It is also preferable.

  In the robot finger unit according to the present invention, the drive cable preferably includes a first cable and a second cable.

  In the robot finger unit according to the present invention, each of the n + 1 vertical axles includes a first pulley and a second pulley, and an intermediate portion of the first cable is wound around the first pulley along the rotational direction 1, It is also preferable that the middle part of the cable is wound around the second pulley along a rotational direction 2 different from the rotational direction 1.

  In the robot finger unit according to the present invention, the second member includes a rotary tension adjusting member and a fixing member, and the other end of either the first cable or the second cable is wound around the rotary tension adjusting member. It is also preferable that the other end of either the first cable or the second cable is fixed to the fixing member.

  In the robot finger unit according to the present invention, either one end of the first cable or one end of the second cable that is wound and fixed around the rotary tension adjusting member is wound around the rotation axis in the clockwise direction and fixed. It is also preferable that one end of the first cable whose end is fixed to the fixing member and the other of the one end of the second cable are wound around the rotating shaft in a counterclockwise direction and fixed.

  Since the robot hand according to the present invention controls the bending operation of the robot finger unit using a drive cable and a pulley, when gripping an object, the angle formed between the members is the shape of the object to be gripped. The optimal angle. As a result, the degree of freedom of the robot hand increases and the contact between the member and the object becomes closer.

It is a schematic diagram which shows an example of the robot hand which concerns on this invention. It is a side surface schematic diagram which shows the drive mechanism of the robot hand unit which concerns on this invention. It is an elevation model which shows the drive mechanism of the robot hand unit which concerns on this invention. It is a schematic diagram which shows the state which wound the intermediate part of the drive cable of the robot finger unit which concerns on this invention around the pulley.

  In order that the objects, features, and advantages of the present invention will be more clearly understood, embodiments will be described below and described in detail with reference to the drawings.

  A robot hand 100 shown in FIG. 1 includes a base 200, three sets of robot finger units 300, and three sets of drive mechanisms D. The robot finger unit 300 is rotatably connected to the base 200. The drive mechanism D is connected to the base 200, and each drive mechanism D is connected to the corresponding robot finger unit 300 and drives the robot finger unit 300 to bend and grip an object.

  Here, although the robot finger unit 300 provided in the robot hand 100 shown in FIG. 1 is three sets, the robot finger unit 300 connected to the base 200 is not limited to three sets. If the robot hand 100 includes at least two sets of robot finger units 300, the robot hand 100 can grip an object. Further, a plurality of robot finger units 300 can be added to the robot hand 100 depending on the purpose of use. In that case, the object can be gripped more firmly.

  The configuration and driving method of each robot finger unit 300 will be described below. Each robot finger unit 300 shown in FIGS. 2 and 3 includes a first member 301, a second member 302, an intermediate member 303, two axles W, two pulleys 400, and a rotary tension adjusting member 500. The fixing member 600 is provided.

  First, the first member 301 is connected to the base 200, and the intermediate member 303 is connected to both the first member 301 and the second member 302. The axle W is arranged to connect two adjacent members, the first member 301 and the intermediate member 303 are rotatable about the axle W, and the second member 302 and the intermediate member 303 are also axles W. It can be rotated around the center.

  In this embodiment, the robot finger unit 300 includes the first member 301, the second member 302, and the intermediate member 303. However, the present invention is not limited to this. If the robot hand 100 includes at least the first member 301 and the second member 302, the robot hand 100 can grip an object. Therefore, the arrangement of the intermediate member 303 is not essential. A plurality of intermediate members 303 may be provided, and the number of intermediate members 303 to be arranged may be determined according to the purpose of use. At this time, the number of axles W and pulleys 400 arranged between the core members may be determined from the number of connecting portions between the members.

  As shown in FIG. 3, the pulley 400 includes a first pulley 401 and a second pulley 402, and the first pulley 401 and the second pulley 402 are freewheels, and are loosened with respect to each axle W. There are provided. The rotary tension adjusting member 500 and the fixing member 600 are disposed on the second member 302. The rotary tension adjusting member 500 is a member that requires a predetermined torque to rotate in a predetermined direction. The drive mechanism D includes a motor M and a rotary shaft A. The motor M is connected to the base 200 and the rotary shaft A is connected to the motor M as shown in FIG. The rotating shaft A is driven by the motor M and rotates clockwise or counterclockwise. Note that the drive mechanism D of the present embodiment is configured by the motor M and the rotation shaft A, but is not limited to this configuration. The drive mechanism D can also be comprised with an electromagnetic valve, a gear, or another mechanism.

  Further, as shown in FIG. 4, the robot finger unit 300 includes a drive cable 700 including a first cable 701 and a second cable 702. The intermediate portion of the first cable 701 is wound around the two first pulleys 401 along the rotation direction F1, and the intermediate portion of the second cable 702 is wound around the two second pulleys 402 along the rotation direction F2. ing. And the 1st cable 701 and the 2nd cable 702 are each provided with the one end part E1 and the other end part E2. The one end E1 of the first cable 701 and the one end E1 of the second cable 702 are wound around the rotation axis A in the opposite direction and fixed. The other end E2 of the first cable 701 is wound around and fixed to the rotary tension adjusting member 500, and the other end E2 of the second cable 702 is fixed to the fixing member 600.

  Note that one end E1 of the first cable 701 and one end E1 of the second cable 702 are wound around the rotation axis A in the opposite direction. Therefore, when the rotation axis A rotates clockwise, Pull one cable and loosen the other cable. The same applies to the case of counterclockwise rotation. Therefore, there is no particular limitation on which direction of the rotation axis A the first cable 701 and the second cable 702 are wound around, and the first cable 701 and the second cable 702 are rotated in the opposite directions. What is necessary is just to be fixed in the state wound around A.

  When the robot hand grips an object, for example, the motor M is driven to rotate the rotating shaft A clockwise, the other end is wound around the rotary tension adjusting member, and the first cable 701 is fixed. The second cable 702 having the other end fixed to the fixing member is loosened. In this way, each robot finger unit 300 bends in a direction facing each other, so that an object can be held between the robot finger units 300. On the other hand, when the motor M is driven in the reverse direction and the rotating shaft A is rotated counterclockwise, the first cable 701 is loosened and the second cable 702 is pulled, so that the robot finger units 300 face each other in a bent state. Operates in the direction to eliminate, and releases the object.

  More specifically, the pulley 400 around which the intermediate portion of the drive cable 700 is wound is a free wheel. Therefore, by adjusting the tension of the drive cable 700, the bending operation level of the robot finger unit 300 formed by the first member 301, the second member 302, and the intermediate member 303 can be controlled. Specifically, when the first cable 701 having the other end wound around the rotary tension adjusting member is pulled, the intermediate member 303 rotates about the axle W with respect to the first member 301, and the second member 302. Rotates about the axle W with respect to the intermediate member 303. At this time, each member rotates to an angle adapted to the shape of the object to be grasped. More specifically, the intermediate member 303 rotates about the axle W with respect to the first member 301, and when the intermediate member 303 contacts the object, the intermediate member 303 does not rotate any more. However, the second member 302 further rotates around the axle W with respect to the intermediate member 303 until the second member 302 contacts the object. In other words, if the second member 302 rotates with respect to the intermediate member 303 until it contacts the object, the second member 302 does not rotate any further. However, the intermediate member 303 further rotates around the axle W with respect to the first member 301 until the first member 301 and the object come into contact with each other. As a result, the object can be firmly held between the robot finger units 300.

  To summarize the above description, the robot hand 100 according to the present invention uses the drive cable 700 and the pulley 400 to control the bending operation of the robot finger unit 300. An optimum gripping angle is formed with respect to the shape of the object. As a result, the contact between the object and each member becomes closer, and at the same time, the degree of freedom of operation of the robot hand increases.

  As mentioned above, although suitable embodiment which concerns on this invention was illustrated, in description of a figure or description, the same code | symbol is used for the same or same part. Moreover, in the figure which shows embodiment, shape or thickness is deformed or a display is simplified. Further, the present invention is not limited to each component described in the drawings. Accordingly, those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the rights claimed by the present invention is based on the claims.

100 robot hand 200 base 300 robot finger unit 301 first member 302 second member 303 intermediate member 400 pulley 401 first pulley 402 second pulley 500 rotary tension adjusting member
600 Fixing member 700 Drive cable 701 First cable 702 Second cable A Rotating shaft
D drive mechanism E1 one end E2 other end F1 rotation direction 1
F2 Rotation direction 2
M Motor W Vertical axle

Claims (6)

A robot finger unit having a gripping operation function,
A base, a driving mechanism fixed to the base and provided with a rotating shaft, and a parallel axle having one end parallel to the rotating shaft and a parallel axle set as the rotating shaft to be capable of rotational movement. A first member, and a second member connected to the first member so as to be rotatable about the vertical axle as a rotation axis via a vertical axle installed perpendicularly to the rotation axis on the other end side of the first member; A pulley and a drive cable that are rotatably installed on the vertical axle as the rotation axis.
The robot cable unit according to claim 1, wherein the drive cable includes a first end portion wound around and fixed to the rotating shaft, a second end portion fixed to the second member, and an intermediate portion wound around the pulley. 2. The robot finger unit according to claim 1, further comprising n intermediate members connected via n + 1 (where n is an integer of 1 or more) vertical axles between the first member and the second member. . The robot finger unit according to claim 1 or 2, wherein the drive cable includes a first cable and a second cable. Each of the (n + 1) vertical axles includes a first pulley and a second pulley, and the intermediate portion of the first cable is wound around the first pulley along the rotational direction 1, and the intermediate portion of the second cable The robot finger unit according to claim 1, wherein the robot finger unit is wound around the second pulley along a rotation direction 2 different from the rotation direction 1. The second member includes a rotary tension adjusting member and a fixing member, and the other end of one of the first cable and the second cable is wound around and fixed to the rotary tension adjusting member, The robot finger unit according to any one of claims 1 to 4, wherein the other end of the other of the first cable and the second cable is fixed to the fixing member. Either one of the one end of the first cable or the one end of the second cable, the other end of which is wound around the rotary tension adjusting member and fixed thereto, is wound around the rotating shaft in a clockwise direction and fixed. The other end of the first cable having the other end fixed to the fixing member and the other of the one end of the second cable are wound around the rotation shaft in a counterclockwise direction and fixed. The robot finger unit according to any one of claims 1 to 5.

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