Injection mold adjustment device
The injection molding mold adjustment device is the core component of the injection molding machine that realizes mold closing, locking, and adjusting mold thickness. Its performance directly affects the molding accuracy of plastic parts, production efficiency, and the operating stability of the equipment. The main functions of the mold adjustment device include: driving the movable platen to move to realize the opening and closing of the mold; providing sufficient clamping force during the injection molding process to prevent the melt from overflowing the mold cavity due to high pressure; adjusting the distance between the movable platen and the fixed platen according to the different thicknesses of the mold to ensure that the mold can be closed accurately. Common injection molding mold adjustment devices can be divided into three types: mechanical, hydraulic, and electro-hydraulic composite. Different types of devices have significant differences in structural design, working principles, and applicable scenarios.
Mechanical mold adjustment devices are widely used in small and medium-sized injection molding machines due to their simple structure, low cost, and easy maintenance. Their core structure typically consists of a transmission mechanism, such as a worm gear, rack and pinion, or a lead screw nut. A motor drives these transmission components, which in turn move the movable platen to adjust the mold thickness. For example, in a worm gear mold adjustment device, a motor rotates the worm, which meshes with a worm wheel fixed to the movable platen, converting the rotational motion into linear motion of the movable platen, thereby adjusting the mold gap. This device offers relatively low mold adjustment accuracy and a low clamping force, but it responds quickly, making it suitable for producing smaller, simpler parts. During use, transmission components must be regularly lubricated and inspected for wear to prevent inaccurate mold adjustment due to poor gear engagement or lead screw jamming.
Hydraulic mold adjustment devices, with their advantages of high clamping force, high mold adjustment precision, and smooth operation, have become a dominant force in large-scale injection molding machines and the production of precision plastic parts. This device primarily consists of a mold adjustment cylinder, a clamping cylinder, a hydraulic valve block, and a control system. The hydraulic oil pressure drives the piston, enabling movement of the movable platen and control of the clamping force. The hydraulic mold adjustment device precisely controls the flow and pressure of the hydraulic oil via a proportional valve or servo valve, achieving stepless adjustment of mold thickness with an adjustment accuracy of within 0.1mm. Furthermore, its clamping force can be flexibly adjusted based on the molding requirements of the plastic part, preventing mold deformation due to excessive clamping force or flashing due to insufficient clamping force. In high-pressure, high-speed injection molding scenarios, the hydraulic mold adjustment device’s cushioning properties effectively reduce impact and vibration during mold opening and closing, extending the service life of the mold and equipment.
The electro-hydraulic composite mold adjustment device is a new mold adjustment structure that combines the advantages of mechanical and hydraulic methods. It uses an electric motor as its power source and achieves rapid movement of the movable mold plate through precision transmission components such as ball screws. It also utilizes a hydraulic system to provide clamping force, resulting in fast mold adjustment, high precision, and strong clamping force. This device is typically equipped with a servo motor and high-precision sensors that can monitor the position of the movable mold plate and the clamping force in real time. Dynamic adjustments are made through a closed-loop control system to ensure positional accuracy and clamping force stability during the mold opening and closing process. Electro-hydraulic composite mold adjustment devices have lower energy consumption and faster response speeds than traditional hydraulic methods. They are increasingly used in the production of high-end plastic parts such as new energy vehicle parts and precision electronic components. However, their structural complexity and manufacturing costs are relatively high, and they also require a higher level of technical expertise from maintenance personnel.
Routine maintenance and care of injection molding mold adjustment devices are crucial to ensuring their performance. First, regularly check the lubrication of transmission components (such as gears, screws, and guide rails) and promptly add or replace lubricants to prevent wear due to excessive friction. Secondly, for hydraulic mold adjustment devices, regularly clean the hydraulic oil filter and check the hydraulic lines for leaks to ensure stable hydraulic system pressure. Furthermore, position sensors, pressure sensors, and other sensing components must be calibrated to ensure measurement accuracy and avoid inaccurate mold adjustment due to sensor errors. Furthermore, when switching between molds of different specifications, manually adjust the mold adjustment device to confirm smooth opening and closing before resuming automatic operation to prevent equipment collisions caused by mold thickness measurement errors. Through scientific maintenance and proper use, injection molding mold adjustment devices can maintain stable operating conditions over the long term, providing a reliable guarantee for efficient injection molding production.
