Abstract: An injection molding machine mold clamping device (1) comprising an electromechanical mold opening and closing mechanism, a hydraulic mold clamping. mechanism, and a mold thickness adjustment device, said mold thickness adjustment device comprising a first detection device (70) for detecting the position of a mold clamping ram (51), a second detection device (90) for optically detecting the position of a half nut device (20), and a mold clamping ram position control device (90) for hydraulically holding and controlling the position of the mold clamping ram (51). The position of the half nut device (20) is held by hydraulic control at the mold thickness adjustment position during mold opening and closing. In the initial mold opening and closing operation, the large mold opening force exerted by the mold clamping ram (51) may be used to open the mold.

Abstract: In order to eject resin leaked from an injection chamber (13) toward the shaft side of an injection plunger (31) away from an injection cylinder (30), a plunger-type injection molding machine injection device is equipped with an ejection guide (151, 251) at the rear edge of an injection cylinder which is thermally isolated from the injection cylinder main body. A band heater (53), which heats the ejection guide, is controlled independently of the band heater (38) which heats the injection cylinder. One embodiment of this injection guide (151) causes the ejected resin to fall from the ejection opening (151h) while retaining its molten state. In another embodiment, the ejection guide (251) has ejection channels (251f) which cause the resin to harden and be ejected in a fine strand state.

Abstract: When a process measurement metering operation is performed during a molding cycle, a plunger is forcibly caused to retract to a position behind measurement metering completed position, while at the same time a periodic forced purge operation is implemented in which the plunger is immediately restored to the vicinity of the position at which the forced retraction operation commenced. By this operation, leaked resin is removed to the rear, i.e., beyond the plunger metering stroke range, and any increase in resistance to movement of the plunger due to disposition of leaked resin is avoided. The forced purge operation is preferably performed either immediately prior to the normal metering operation, or after a specified time has elapsed following completion of a metering operation.

Abstract: Molten resin, plasticized in the plasticization chamber, is fed to the injection chamber through a connection passage where it is measured. Before it is injected by the plunger, the connection passage is blocked and the molten resin is preliminarily compressed. This invention provides a method using a preplasticization type injection molding machine that controls the volume of the filled molten resin with little variation utilizing blocking and preliminary compression. By means of blocking or preliminary compression, the position movement by which the plunger moves from the position at which the measurement is completed is calculated, and the position at which the next measurement will be complete is corrected. Furthermore, the molten resin fill operation is done on the basis of the position of the plunger detected at the time of the preliminary compression.

Abstract: An injection molding machine having an injection plunger (21) capable of moving back and forth within an injection chamber (22) includes a scraper ring (23) attached to one end of an injection cylinder (2) having a hole penetrated by the injection plunger. A protuberance (23a), which forms the smallest diameter portion of the hole penetrating the scraper ring and extends to the surface of the injection plunger, is formed on the inside wall of that scraper ring. The perimeters (23e, 23h) of this protuberance scrape off any molding material which adheres to the injection plunger. The scraper ring has windows (23f, 23g) for the purpose of dropping scraped-off material outside thereof. Preferably, the injection plunger has a shank (21b) and a head (21a) which forms the tip of the injection plunger and which has a diameter larger than the shank and slightly smaller than the injection chamber; the protuberance of the scraper ring has a diameter which is slightly larger than the shank and smaller than the head.

Abstract: A pre-plasticization type injection molding machine is equipped with a plasticizing part for plasticizing synthetic resin material by turning a screw in a heating cylinder and an injection part for injecting the plasticized material through a nozzle by advancing and retreating an injection plunger into and from an injection cylinder. A conduit connects the tip of a plasticizing chamber, consisting of the heating cylinder, with the tip of an injection chamber consisting of the injection cylinder. The screw advances at the time of injection, closes the conduit with its tip. The opening of the conduit in the injection chamber is arranged on the periphery of a nozzle side-wall. An injection passage extends from the injection chamber toward the nozzle, the passage being open to the center of the nozzle side-wall.

Abstract: In an electrode mounting device having a fixed coupling member and a removable coupling member, one coupling member has positioning projections and the other coupling member has a groove or grooves for receiving the positioning projections. These positioning projections are engaged with the grooves each other keeping a line contact or a point contact therebetween. As a result, if dust or chip is placed on the positioning projections or grooves of the coupling members, the coupling members can be accurately coupled. Furthermore, high precision is not necessarily required in preparation of the coupling members.

Abstract: At least one pair of regulating blocks are provided on a base table so as to move on a major face of the base table in parallel therewith. Each of said pair of regulating blocks has a holding face with a regulating face so as to position a member to be adjusted in a desired angle. The member to be adjusted is held by the holding faces of the respective regulating blocks and, as a result, the member is positioned in the required angle following the regulating faces of the respective holding faces. With the so constructed device of the present invention, the member to be adjusted can be easily positioned with respect to its angle simply by holding the member by at least one regulating blocks.