1. Field of the Invention
The present invention relates to a finishing machine for removing a burr, from a surface of a workpiece such as a mechanical part, by a robot.
2. Description of the Related Art
Concerning methods of removing a burr from a workpiece such as a mechanical part, a method of automatically removing the burr by a robot is known. According to the method, under the condition that the workpiece is fixed at a predetermined position, a machining tool for removing the burr is attached to the robot. Next, by means of pressure control, in which a mechanical floating mechanism operated by a spring or pneumatic pressure is used, or by means of pressure control in which software is used, while the machining tool is being pushed onto a surface of a workpiece, on which the burr is formed, at a predetermined force, the surface of the workpiece, on which the burr is formed, is moved so that the burr can be removed. The following method is also employed. Under the condition that the machining tool for removing the burr is fixed at a predetermined position, the workpiece is held by the robot, and while the workpiece is being pushed onto the machining tool for removing the burr at a predetermined force, the workpiece is moved so that the burr can be removed from the workpiece.
The size of the burr formed on the workpiece is not constant, that is, the size and the position of the burr formed on the workpiece are different for each individual workpiece. In the case where the size of the burr is relatively large, this burr cannot be removed by one cutting action for burr removing. In this case, it is necessary to change the depth of cut of the burr and conduct the burr cutting action a plurality of times. Conventionally, on the assumption that the burr, the size of which is relatively large, is formed on the workpiece surface, the burr removing action or cutting action is conducted a plurality of times. In this case, even when only a burr, the size of which is relatively small, is formed, the burr removing action is conducted on the workpiece by a plurality of times. As a result, useless burr removing actions may be conducted.
Further, in the burr removing action, the burr is cut while the machining tool is being pushed onto the workpiece by a predetermined force. Therefore, the machining tool is pushed to a portion, which does not need to be cut, in the cutting action. Accordingly, there is a possibility that overcut portions of the workpiece may be generated.
It is an object of the present invention to provide a finishing machine by which the useless burr removing action is reduced and further the overcutting of a workpiece is prevented.