One, reset mechanism
After the injection molded part is demolded, the demolding mechanism needs to return to its original position to facilitate the demoulding after the next injection molded part. There are many forms of reset mechanism, and the commonly used one is to use the return rod to play the role of reset. When demoulding, the push rod can push the injection part out of the mold; when the mold is closed, the fixed template pushes the return rod to realize the reset of the demoulding mechanism.
(1) Screw-type reset rod reset mechanism: When the mold is closed, the reset of the push rod is completed by the reset screw. Due to the large gap between the reset screw and the hole passing through the moving platen and the platen of the moving platen, the displacement of the push rod cannot be guaranteed, and a guide column needs to be used for guidance. In order to ensure the accurate reset of the demolding mechanism, the A surface of the movable platen needs to be ground in combination with the reset screw.
(2) Return lever type reset mechanism: The end face of the return lever must be flush with the parting surface. After the mold is opened, the injection molded parts are pushed out of the mold cavity under the action of the push rod; when the mold is closed, the return rod pushes the demolding mechanism to reset under the action of the fixed template.
(3) Push rod and reset rod type reset mechanism: the upper end face of the push rod must be flush with the parting surface. This is a reset mechanism of a commonly used demolding mechanism, which is characterized in that part of the end face of the push rod is in contact with the injection molded part, and the other part is in contact with the fixed template, so that when the push rod is ejected, the push rod plays the role of ejecting the injection molded part. When the mold is closed, the push rod plays the role of reset again.
Second, reset the mechanism first
In the design of injection mold reset and first reset mechanism, when the core of the injection mold core-pulling mechanism overlaps with the projection of the push rod of the demolding mechanism, if the demolding mechanism cannot be reset before the core-pulling mechanism, a push rod will occur. Collision with the core. At this time, the push rod must be reset before the core of the core-pulling mechanism. This mechanism that resets the push rod first is called the first reset mechanism. There are many types of first reset mechanisms. Here, only the spring type, oblique pin type, rack and pinion type and hinge type first reset mechanism are introduced to introduce the push rod and reset rod reset mechanism. In addition, there are also pre-reset mechanisms such as link type, pendulum block type, sliding shaft type and lever type.
