Injection-molded rocker-type reset mechanism
The injection molding rocker-type pre-reset mechanism is a crucial feature of injection molds. Its primary function is to ensure that the ejector mechanism resets before the side core pull mechanism during the mold closing process, preventing interference between the two and ensuring proper mold operation and product quality. This mechanism typically consists of a rocker, a reset lever, and a guide. Its operating principle is to utilize the dynamic force during mold closing to drive the rocker, thereby prematurely resetting the ejector mechanism. Compared to other pre-reset mechanisms, the rocker-type pre-reset mechanism offers advantages such as simple structure, reliable operation, and easy installation and commissioning, making it widely used in a variety of complex injection molds.
The structural design of the rocker-type pre-reset mechanism has a crucial impact on its performance. The length, shape, and connection method of the rocker with other components will directly affect the movement accuracy and reset effect of the mechanism. If the rocker is too long, it will lead to insufficient rigidity and easy deformation during movement, affecting the accuracy of reset; if it is too short, it may not provide sufficient thrust, so that the ejection mechanism cannot be reset in time. The connection between the rocker and the reset rod usually adopts a hinge structure to ensure that the rocker can rotate flexibly. At the same time, the strength of the connection must be ensured to avoid wear or breakage during long-term use. The design of the guide device cannot be ignored either. It can ensure that the rocker and the reset rod move along the predetermined trajectory during movement, prevent deviation or jamming, and ensure the stable operation of the mechanism.
During the mold closing process of an injection mold, the operation of the rocker-type pre-reset mechanism can be divided into several key stages. When the movable mold and the fixed mold begin to close, the stopper on the fixed mold will first contact one end of the rocker, pushing the rocker to rotate around the fulcrum. As the mold closing action continues, the other end of the rocker will gradually contact the reset rod of the ejection mechanism and apply a thrust to it. Under the action of the thrust, the ejection mechanism begins to move upward, achieving reset. When the ejection mechanism is fully reset, the rocker disengages from the reset rod, the mold closing action continues, and the side core pulling mechanism begins to operate, completing the core pulling action. Throughout this process, the rocker-type pre-reset mechanism can accurately control the reset time of the ejection mechanism, ensuring that it resets before the side core pulling mechanism, effectively avoiding interference between the two.
During the design and application of a rocker-type pre-reset mechanism, multiple factors need to be considered to ensure its reliability and applicability. The first is the strength and wear resistance of the mechanism. Since the rocker and reset rod frequently come into contact and move during operation, they are prone to wear. Therefore, high-strength, high-wear-resistant materials must be selected to manufacture these components, and appropriate heat treatment must be performed to increase their service life. Secondly, the fulcrum position and travel range of the rocker must be reasonably determined based on the specific structure of the mold and the reset requirements of the ejection mechanism to ensure that the mechanism can provide sufficient thrust to complete the reset of the ejection mechanism within the specified time. In addition, the impact of the mold closing speed and pressure on the mechanism must also be considered to avoid damage to the mechanism or abnormal movement due to excessive closing speed or excessive pressure.
With the continuous development of the injection mold industry, rocker-type pre-reset mechanisms are also undergoing continuous improvement and refinement. Some new rocker-type pre-reset mechanisms employ more advanced design concepts and manufacturing processes, improving the mechanism’s motion accuracy and reliability. For example, by optimizing the rocker’s structural shape, the mechanism’s weight is reduced, lowering its motion inertia; while the use of rolling friction instead of sliding friction reduces component wear and increases the mechanism’s service life. Furthermore, with the application of computer-aided design and simulation technology, the motion process of the rocker-type pre-reset mechanism can be accurately simulated and analyzed during the design phase, enabling the timely identification and resolution of potential issues, thereby improving the design quality and efficiency of the mechanism. These improvements and innovations have enabled the rocker-type pre-reset mechanism to be applied in a wider range of fields, providing strong support for the development of injection molds.
