How to determine the parameters of manipulator according to the specifications of injection molding machine and the size of mold?

To determine the parameters of the injection molding manipulator, it is necessary to comprehensively consider the specifications of the injection molding machine, the size of the mold, the production process and other factors. The following are specific methods:

Determine the parameters according to the specifications of injection molding machine

Mold opening stroke: The mold opening stroke of the injection molding machine determines the depth that the manipulator can enter the mold. Generally speaking, the horizontal stroke of manipulator should be greater than the opening stroke of injection molding machine, so as to ensure that the manipulator can reach all positions of the mold cavity smoothly to take parts. Generally, it is suggested that the horizontal stroke of manipulator is 100-200mm larger than the opening stroke of injection molding machine, so as to have enough margin to deal with different positions of the mold and possible unexpected situations.

Template size: the size of the fixed template and the moving template of the injection molding machine determines the installation position and activity range of the manipulator. When selecting the manipulator, make sure that its mounting base can adapt to the template size of the injection molding machine, and the mechanical arm will not interfere with the template during the movement. Generally, the installation position of the manipulator is required to be at least 100-150mm away from the edge of the template to ensure the normal movement of the manipulator.

Ejection mode and stroke: the ejection mode and stroke of injection molding machine will affect the timing and mode of manipulator taking parts. If the injection molding machine adopts mechanical ejection, it is necessary to adjust the picking height and time of the manipulator according to the position and stroke of the ejection rod to ensure that the mechanical arm can accurately grab the product after the ejection action is completed. For injection molding machines with hydraulic ejection or pneumatic ejection, it is also necessary to consider the influence of ejection speed and strength on product removal, and adjust the parameters of manipulator accordingly. Generally speaking, the height of the manipulator should be slightly higher than the height of the product ejected by the injection molding machine to avoid collision with the ejection mechanism.

Determine the parameters according to the die size.

Cavity layout: the cavity layout of the mold determines the position and distribution of injection products in the mold, and then affects the grasping position and quantity of manipulator. According to the arrangement and spacing of cavities, the number of fixtures and the grasping range that the manipulator needs to be equipped with are determined. For example, for a mold with multiple cavities, it is necessary to select a manipulator that can grasp multiple products at the same time, and reasonably adjust the spacing and angle of the fixture to ensure that the products in each cavity can be accurately grasped.

Product size and weight: the size and weight of injection molded products are the key factors to determine the grasping strength of manipulator, the size of fixture and the load capacity of manipulator. Generally speaking, the maximum opening dimension of the fixture should be slightly larger than the maximum external dimension of the injection molded product to ensure that the product can be grasped smoothly. The grasping strength should be determined according to the weight and surface material of the product, so as to ensure that the product can be firmly grasped without damaging the product due to excessive force. At the same time, the manipulator's mechanical arm load capacity should be greater than the total weight of the grabbed products, and it is generally recommended to leave a margin of 20%-30% to cope with possible overweight or future product size and weight changes.

Mold depth: The depth of the mold determines the length that the manipulator arm needs to extend into the mold. When selecting manipulator, the vertical stroke of its mechanical arm should meet the requirements of mold depth, and it will not interfere with the side wall or other parts of the mold when it extends into the mold. Generally, the vertical stroke of the mechanical arm is required to be 50-100mm greater than the depth of the mold, so as to ensure that it can reach the bottom of the mold smoothly to take the parts.

Determining parameters considering production process

Production cycle: the production cycle specified in the production process determines the action speed and cycle time of the manipulator. In order to match the production rhythm of the injection molding machine, the manipulator needs to complete the operations of taking and putting parts in a specified time. Therefore, it is necessary to reasonably adjust the movement speed, residence time and other parameters of the manipulator according to the production cycle to ensure its efficient and stable operation. Generally speaking, under the premise of ensuring product quality and equipment safety, the movement speed of manipulator should be increased as much as possible to shorten the single cycle time and improve production efficiency.

Cooling time: The cooling time of injection molding products will affect the picking time and operation mode of the manipulator. If the cooling time is short, the product may not be completely cooled and shaped. At this time, the manipulator needs to adopt a gentle grasping method to avoid product deformation caused by external force. On the contrary, if the cooling time is long, the manipulator can increase the grasping strength appropriately to improve the efficiency of taking parts. At the same time, the waiting time and picking opportunity of the manipulator should be arranged reasonably according to the cooling time, so as to ensure that the picking operation can be carried out in time when the product reaches the ready-to-take state.

Stripping mode: Different stripping modes also have certain requirements for the parameters of the manipulator. For example, for the mold with forced demoulding, the manipulator needs to grab the product quickly and accurately at the moment of demoulding to prevent the product from being damaged during demoulding. However, for the mold with natural demoulding or auxiliary demoulding, the time and method of taking parts from the manipulator are relatively flexible. Therefore, it is necessary to adjust the parameters of the manipulator, such as the picking speed, grabbing position and strength, according to the demoulding mode of the mold to ensure that the product can be demoulded smoothly and taken out accurately.