Abstract: A mold locking device for a molding machine has a toggle assembly, and a transmission member. The toggle assembly has first toggle arms pivoted to a bearing disc of the molding machine, connecting arms pivoted to a movable mold base, second arms pivoted to both the first arms and the connecting arms, and has third arms pivoted to both the second arms and a co-moving disc movable between the bearing disc and the movable mold base. The transmission member has a power, a connecting member and an elongated screw. The connecting member connects the power and a nut turnably fitted on the co-moving disc; the screw is passed through the nut for permitting the nut to turn relative to, and move along, the screw. The screw is further connected to the movable mold base such that the movable mold base can be moved between a mold opening position and a closing position by the toggle assembly and the power.

Abstract: An arm structure for an injecting molding machine includes a first arm, a second arm, a third arm and an oil pressure cylinder. The cylinder is positioned between a receiving disc and a movable mold base. The second arm and the third arm consist of plural pivotal plates located separately at two sides of the cylinder with a distance a little larger than the outer diameter of the cylinder. Further, the space between the two joints of the second arm and the third arm is a little larger than the outer diameter of the cylinder. So the two joints of the second and the third arms can pass the cylinder without colliding with the cylinder when the arm structure operates to move back and forth in opening and closing the mold. Thus, the size of an injecting molding machine is reduced to save transporting and packaging cost and needed space for installation.

Abstract: An arm structure for an injecting molding machine includes arms consisting of two pairs of two arms respectively having plural parallel pivotal plates having two ends pivotally connected with plural position plates of a receiving disc and a movable mold base. Each position plate has an outer end concave surface with a threaded hole. Each pivotal plate has an outer end is bored with a pivot hole and fits in a gap between every two position plates. Further, a tubular pivot has plural through holes spaced apart corresponding to the threaded holes of said outer end concave surfaces of the position plates for bolts to pass through and screw with the threaded holes. Then the arm structure is pivotally connected to the receiving disc and the movable mold base. Therefore, the arm structure is easily assembled with or disassembled from the receiving disc and the movable mold base by only screwing off the bolts, without need of removing the connecting rods.

Abstract: An arrangement of oil cylinders of a plastic injecting machine is provided which positions a large oil cylinder and a small oil cylinder respectively on both the left and right sides of an oil cylinder base and a bearing base. The large and small oil cylinders are located at such a distance away from a material injecting cylinder that the oil seals of the four oil cylinders are not heated by the electric heaters that heat the material injecting cylinder. By this arrangement, the oil seals have a normal service life. In addition, an oil route plate is located on the bearing base to secure oil pipes formed of hard steel connected between the four oil cylinders and an oil pump, to keep oil flowing smoothly.

Abstract: A mold locking device for an injection molding machine is provided. The device includes a stationary disc and a movable disc displaceable to lock a mold placed between the stationary disc and the movable disc. Four oil cylinders are provided to move the movable disc on four guide rods back and forth. Four push rods are provided, each having a front end secured to the movable disc and a rear end extending through four cylindrical tubes disposed with a respective one of four holes formed in a support disc. A piston disposed within a piston chamber formed in a front surface of the support disc is pushed forward to respectively push a shield plate. The shield plate displaces the four push rods so as to push the movable disc with a great force, after the movable disc has been pushed forward to lock the mold stably.