Multi-joint type industrial robot

• US 20030085681A1
• Filed: 10/09/2002
• Published: 05/08/2003
• Est. Priority Date: 10/17/2001
• Status: Active Grant

• Current Assignee: Japan Servo Co., Ltd. (Nidec Corporation), Tazmo Co., Ltd.
• Original Assignee: Japan Servo Co., Ltd. (Nidec Corporation), Tazmo Co., Ltd.
• Inventors: Sakamoto, Masafumi, Kobiki, Takahiro, Endo, Kaoru, Yamazoe, Katsuhiro
• Granted Patent: US 6,781,337 B2
• Time in Patent Office: Days
• US Class Current: 318/568.16
• CPC Class Codes: B25J 19/0025 Means for supplying energy to the end effector
• CPC Class Codes: B25J 9/042 comprising an articulated arm
• CPC Class Codes: H01R 39/64 Devices for uninterrupted current collection

Abstract

In an industrial robot having a plurality of arms, each arm is coupled with other elements such as a mounting base, another arm, a robotic hand, and revolved by a motion of the revolute joint. The revolute joint has a rotary electric connecting structure such as a slip ring or a rotary transformer which can be rotated endlessly. Electric powers for driving motors by which the arms are revolved and control signals for controlling the driving of the motors are supplied or transmitted through the rotary electric connecting structure, so that the arms can be rotated endlessly without twisting or breaking of electric cables.

Claims

1. An industrial robot having a plurality of arms coupled by a plurality of revolute joints, each of the arms can be moved by a driving force of a motor which drives each of the revolute joints, wherein

each of the revolute joints can be rotated endlessly, and has a rotary electric connecting structure which can be rotated endlessly at least for supplying an electric power from a control circuit to the motor.

2. The industrial robot in accordance with claim 1, wherein

the rotary electric connecting structure is a slip ring structure having a plurality of conductive rotary members which can be rotated corresponding to revolution of the arm and a plurality of conductive stationary members which is not rotated corresponding to the revolution of the arm, and electric connection is realized by slipping contact of the rotary member and the stationary member.

3. The industrial robot in accordance with claim 2, wherein

each of the revolute joints further has an encoder for sensing a revolution angle of each of the arms;

a rotation shaft of the encoder is integrally coupled with a rotation shaft of the slip ring structure; and

the slip ring structure is further used for transmitting a sensing signal from the encoder to the control circuit.

4. The industrial robot in accordance with claim 1, wherein

the rotary electric connecting structure is a rotary transformer having a rotary secondary coil which can be rotated corresponding to revolution of the arm, and a stationary primary coil which is not rotated corresponding to the revolution of the arm, and electric connection is realized by electromagnetic interactive induction between the stationary primary coil and the rotary secondary coil.

5. The industrial robot in accordance with claim 4, wherein

each of the revolute joints further has an encoder for sensing a revolution angle of each of the arms;

a rotation shaft of the encoder is integrally coupled with a rotation shaft of the rotary transformer; and

the rotary transformer is further used for transmitting a sensing signal from the encoder to the control circuit.

6. The industrial robot in accordance with claim 5 further comprising:

a plurality of modulator/demodulator for modulating the electric power supplied from the control circuit and control signals transmitted from the control circuit to other signals which can be electrically connected by the electromagnetic interactive induction of the rotary transformer, and for demodulating the modulated other signals to the electric power and the control signals.