Abstract: A mold clamping device in an injection molding machine comprises a first platen for retaining a first mold therein and a second platen for retaining a second mold therein; a platen feeding mechanism for moving said first and second platens relative to each other on said table; electromagnetic coils arranged on the opposite surfaces of the first and second platens; and a control device for controlling the amount of the current supplied to the electromagnetic coils. The mold clamping operation is carried out using the magnetic attracting force generated by the electromagnetic coils.

Abstract: A mold clamping device in an injection molding machine comprising a stationary electromagnetic plate and a movable electromagnetic plate provided at the side of the stationary electromagnetic plate away from the movable platen so as to be capable of being moved toward and away from the stationary electromagnetic plate. Both electromagnetic plates are each provided with an electromagnetic coil for generating a magnetic attracting force. The device further comprises a movable platen driving mechanism which is composed of a combination of a feed screw shaft and a nut member and is connected to the movable platen. An operation for closing the molds is performed by the driving mechanism. Subsequently, a mold clamping operation of both molds is performed by a magnetic attracting force from the electromagnetic coil.

Abstract: A polishing machine has an upper polishing plate and a lower polishing plate provided below the upper polishing plate. The upper polishing plate has slurry passages. Plugs for supplying slurry are detachably quick coupled to the slurry passages. A piece of polishing pad is bonded to the lower surface of the upper polishing plate. After a spent polishing pad has been removed and a fresh polishing pad has been attached to the lower surface of the upper polishing plate, a hole-cutter is downwardly inserted in each slurry passage until it pierces the fresh polishing pad, thus cutting a hole in the polishing pad.

Abstract: A polishing machine for polishing the surfaces of the workpieces to be processed has upper and lower surface plates which are rotated relative to each other. A plurality of carriers are placed between the upper and lower surface plates and each of the carriers has a plurality of bores into which the workpieces are fitted. These carriers are engaged with both the sun gear and the internal ring gear within the same plane. In account of the sun gear and the internal ring gear, the carriers are rotated round the sun gear, turning round their own axes. The internal ring gear can be lifted up and down by a lift mechanism. The sun gear is slidably attached to a hollow driving shaft and has a feed screw which is engaged with a feed nut. This feed nut is rotatably fitted onto the hollow driving shaft in such a way that the nut is limited of its movement in the axial direction.