ROBOT

Abstract: A robot comprising an articulated manipulator, which is installed on a base that houses electric circuits (for example, a welding power source) for driving and controlling tools (for example, a welding torch) held by the robot. This robot thus saves the space for the installation thereof, and requires a shorter time for installation and fewer parts, whereby it becomes possible to reduce the manufacturing cost, simplify a robot installation operation and obtain a stable welding performance.

Description: The present invention relates to a robot as defined in the preamble part of claim 1. In the past, generally, a welding robot comprised three elements, i.e., a robot body (a manipulator), a robot control unit (a control panel) and a welding power source (including a wire feed mechanism), wherein the welding robot and the welding power source are installed in separate locations, and the robot and the welding power source are connected by a welding output cable. However, there is a problem in that since the installation location for the robot and the installation location for the welding power source are independently required, a large installation space needs to be secured. Instead of such a robot, there is disclosed a method for housing an arc welding power source in a robot control panel. JP-A-4-365581 discloses one such known method. However, since a long welding output cable to connect the robot to the welding power source is necessary, inductance of the cable is so high that detection of short-circuiting timing delays and the short-circuiting time is thus overly long, making the arc unstable. Further, the rising time of the current is extended, preventing smooth shifting to the arc, and resulting in an unstable arc. JP-A-60-158987 is known to show an improvement in a robot as described above, and discloses a spot welding robot in which a welding power source (a transformer and a commutator) is provided at an extreme end of a robot arm. The arrangement of the welding power source at the extreme end of the arm is not preferable because a manipulator having a special construction to withstand the load thereof is necessary, and because the arm portion is excessively large. in EP-A-0 110 347 a robot operation control system is disclosed. There is a control chamber inside a cabinet provided in which an electric circuit for controlling is housed. The document FR-A-2 627 114 which has been used to formulate the preamble part of claim 1 discloses a construction where a casing which contains an electric circuit for driving and controlling operation of a tool held by a robot is located at the side of a robot stand. It is therefore an object of the present invention to provide a robot which minimizes space needed for the installation thereof, and requires a shorter time for installation and fewer parts, whereby it becomes possible to reduce the manufacturing cost, simplify the robot installation operation and obtain a stable welding performance. This object is solved by a robot defined in claim 1. With this arrangement, it is possible to minimize the space needed for installation of an arc welding robot, simplify the installation operation and obtain a stable welding performance. FIG. 1 is a front view showing a preferred embodiment of an arc welding robot according to the present invention with a front lid removed; FIG. 2 is a front view showing a preferred embodiment of an arc welding robot according to the present invention with the front lid mounted; FIG. 3 is a left side view showing a preferred embodiment of an arc welding robot according to the present invention; and FIG. 4 is a back view showing a preferred embodiment of an arc welding robot according to the present invention. The present invention will be described with reference to the drawings. FIG. 1 is a front view showing an arc welding robot according to the present invention with the front lid thereof removed, and FIG. 2 is a front view of the robot with the front lid mounted. FIG. 3 is a left side view of the robot, and FIG. 4 is a back view of the robot. In FIGS. 1 to 4, reference numeral 1 designates an arc welding robot; 1a a welding torch; 2, an arc welding robot stand; 3, a window for an output cable of an arc welding power source; 4, a servo power unit of a motor for the robot; 5, an arc welding power source; 6, a power source plug for supplying power to the servo power unit and the arc welding power source; 7, a plug receptor for an interface; 8, a ventilator; and 9, a blower. In this embodiment, the servo-power unit 4 for the robot motor is also housed in the stand along with the arc welding power source 5 which is an electric circuit for driving and controlling the operation of tools held by the robot body. As shown, stand 2 for arc welding robot 1 houses therein servo-power unit 4 for driving the motor of arc welding robot 1 and arc welding power source 5, air cooling ventilator 8 and blower 9 are provided on the side of stand 2, output cable window 3 is provided on the front surface of stand 2, and power source plug 6 for supplying power to servo-power unit 4 and welding power source 5 and plug receptor 7 for the interface cable connected to a robot controller are provided on the back of stand 2. While in this embodiment, the arc welding robot is shown, the invention is not limited thereto but can be applied to all robots. This can provide a great advantage particularly for situations which require a relatively large electric circuit for driving and controlling tools held by the robot. Further, in the case where the electric circuit for driving and controlling the robot body (manipulator) is housed in the stand as in the above-described embodiment, the circuit which was located within the robot control panel in the past can be transferred to the stand. This produces the additional effect that the robot control panel can be miniaturized. There is a further effect in that if the air cooling means is strengthened, heat generated on the robot body side can also be cooled through the stand. INDUSTRIAL APPLICABILITY As described above, the robot according to the present invention is suited for use in arc welding or the like, among other uses.

Claims: A robot (1) comprising a robot stand (2) having a robot body constituted by an articulated manipulator placed thereon being interiorly provided with an electric circuit for driving and controlling the operation of tools held by said robot body, said tool comprising a welding torch or a welding gun, characterized in that said electric circuit comprises a welding power source (5), and said robot stand (2) which consists of a housing supporting said robot body is also serving as an electromagnetic shield for said electric circuit. The robot (1) according to claim 1, wherein said robot stand is interiorly provided with a blower (9) for air cooling said electric circuit, and a ventilator. The robot (1) according to claim 1 or 2, wherein said robot stand (2) is also interiorly provided with a servo-circuit for driving an electric motor to move said manipulator.

Inventors: HANDA HIROYUKI, MISUMI YUKIO, OKUMURA SHINJI, TANAKA MICHIHARU, HANDA, HIROYUKI, MISUMI, YUKIO, OKUMURA, SHINJI, TANAKA, MICHIHARU, HANDA, Hiroyuki, c/o K.K. Yaskawa Denki, MISUMI, Yukio, c/o K.K. Yaskawa Denki, OKUMURA, Shinji, c/o K.K. Yaskawa Denki, TANAKA, Michiharu, c/o K.K. Yaskawa Denki
Applicants: YASKAWA DENKI SEISAKUSHO KK, KABUSHIKI KAISHA YASKAWA DENKI
Application year: 1996
Main classification: B25J19
IPC codes: B23K9, B25J13, B25J9, B25J19