Abstract: In an injection press having a mold in the form of a moveable die positioned on a moveable plate and a fixed die positioned on a fixed plate, the moveable die is moved to a compression starting position which is spaced slightly from the fixed die, the resin to be molded is injected into the mold cavity between the two dies, and the moveable die is then moved towards the fixed die to compress the thus injected resin. The compression starting position is determined by mechanical positioning means which can adjust the compression starting position. The stroke deviation for the compression can be adjusted by detecting the position of the moveable plate during the compression stroke so that the levelness of the moveable die can always be maintained during the compression stroke. Thus, the parallelism of the two dies can be stably maintained against the injection pressure.

Abstract: The temperatures of structural members of a plastic compression molding machine are controlled so that the socket-and-spigot gap between the dies is maintained at a constant size or so that changes in the socket-and-spigot gap between the dies is maintained below an allowable limit. Working oil for the lift cylinder is passed through passages in at least the bolster, the slide, and the frame. A temperature controller can include heat exchangers and/or flow-rate control valves to control the temperature and/or flow rate of the portion of the working oil to be circulated through the respective structural member.

Abstract: In a combined injection-molding and pressing machine according to the present invention, an injector (10a) of horizontal injection apparatus (10) is disposed below a stationary die plate (2) of a vertical press (1), an injection nozzle (10b) of the injector (10a) is formed into an L-shaped, and the injection nozzle includes a valve (10c) for opening and closing a resin passsage. Corresponding to extension and contraction of the horizontal injection apparatus (10), a base (14) of a platform (4) mounting thereon the horizontal injection apparatus (10) is allowed to slide about the injection nozzle (10), and the L-shaped injection nozzle (10b) is caused to contact with a lower mold (3) at a predetermined surface pressure. Therefore, color changing and purging of resin is more efficient and complete. No need of a hot runner permits to employ an inexpensive and versatile mold that is more widely used in common.

Abstract: A seal assembly for a joint of each pair of adjacent links of an endless track assembly comprising a wear-resistant elastomeric seal ring and a resilient elastomeric load ring. A wear-resistant annular plate is bonded to one of the members of the joint. The load ring is compressed when mounted in place, thus urging the seal ring in sealing contact with the wear-resistant annular plate.