Abstract: When variation of mold clamping force to a mold C in production is detected and the mold clamping force is corrected on the basis of the detected variation, a work load accompanying high-pressure mold clamping of a mold clamping process is used as the variation, a work load as stand-ard (standard work load Ws) accompanying high-pressure mold clamping is preset, the work load accompanying high-pressure mold clamping of the mold clamping process (detection work load Wd) is detected as variation in production, and the mold clamping force is corrected on the basis of a deviation Ke of standard work load Ws from this detection work load Wd.

Abstract: A closure position detection mode is provided so as to obtain a rate of variation (which encompasses an amount of variation) in a physical quantity to a predetermined amount of movement of a movable platen or a crosshead, and detect, as a mold closure position, a position when the variation rate reaches a preset ratio. The mold clamping apparatus is previously operated in the closure position detection mode so as to store, as a reference value, the mold closure position at which a target mold clamping force is obtained. In production operation, the mold clamping apparatus is operated in the closure position detection mode so as to obtain an actual mold closure position (detection value). The mold clamping force is corrected on the basis of a deviation of the detection value from the reference value.

Abstract: In a mold closure position detection method, a mold closure position is detected on the basis of a variation in a physical quantity because of closure of a mold. The method comprises detecting an amount of movement of a movable platen, or a crosshead in the case where the mold clamping apparatus is of a toggle type, during closure of the mold; detecting a variation in the physical quantity because of closure of the mold; obtaining a rate of variation (which encompasses an amount of variation) in the physical quantity to a predetermined amount of movement of the movable platen or the crosshead; and detecting, as a mold closure position, a position of the movable platen or the crosshead when the variation rate reaches a preset ratio.

Abstract: There is provided a preplasticizing injection machine including a resin vent formed in the injection cylinder behind the plunger stroke wherein said resin vent is connected to a pressure reducing device and/or an inert gas feeding machine. The resin entrapped in the clearance prevents gases generated within the cylinder from being exhausted and it may be blackened due to the oxidation thereof. According to the present invention, these problems can be solved by the above construction. Furthermore, a band heater is provided on the outer surface of the cylinder behind the injection plunger stroke over the resin vent to prevent the entrapped resin from being solidified.

Abstract: An injection molding machine equipped with an assembly for vibration processing which efficiently performs processing operations on the resin in the mold with vibration overcomes the restriction of vibration frequency due to the limited response of return springs and due to vibration transfer loss from the vibratory rods to the vibratory plate when operating at a high frequency. The injection molding machine performs both vibration and ejection without an ejector plate by making the vibratory plate serve a dual purpose and thus enable reduction in both mold size and production cost.

Abstract: A method of setting molding conditions for an injection molding machine 1 using a mold 2 whose specifications data are unclear included three setting processes. In the first setting process A, by inputting known data into controller 3, the molding conditions based on a data base prepared in advance and said input known data are set. In the second setting process B, injection molding is performed according to prescribed molding conditions pre-selected concerning injection pressure P, injection speed V and the injection start position of screw 4, and then, based on the product just molded, injection pressure P is altered, to set said altered injection pressure P, injection speed V and proper pre-feed measurement value Md as molding conditions. In the third setting process C, injection molding is performed according to molding conditions obtained from said second setting process B, and subsequently, taking into account the findings from the product just molded, said molding conditions are adjusted.

Abstract: A penetration hole of plasticized resin is pierced in a screw head, so that the resin may be accumulated in uniform temperature distribution without sacrificing the function of the injection screw. More specifically, a penetration hole 15 of plasticized resin is pierced inside a screw head 13 at the front end of a screw 12 from the front middle to the rear periphery so as to communicate between the screw peripheral parts and the screw head front space. A ring valve 17 for opening and closing a rear opening 15a of the penetration hole 15, and closing the gap around the screw head is fitted to the rear periphery of the screw head 13 so as to be free to move back and forth.

Abstract: A continuously variable transmission means having block members, each block member having longitudinal projections causing the rotating radius of the block members to be the same as the rotating radius of an endless carrier, the block members and endless carrier forming a belt which extends between a driving pulley and a driven pulley. When a portion of the belt is in a transition area between a straight extension between the pulleys and moving toward contacting a peripheral portion on one of the pulley, the sliding movement between adjacent block members and the carrier is obviated due to the rotating radius of the block members being equivalent to the radius of the carrier.