What are the causes of product damage during the picking process of injection molding manipulator?

There are many reasons for the damage of the product in the process of picking up the parts by the injection manipulator, involving the manipulator setting, the mold, the product itself and the external environment. The following is a concrete analysis:

Manipulator related factors

Improper grasping force: if the grasping force of the manipulator is too large, it will cause extrusion deformation and even rupture of the product. Especially for some thin-walled and fragile injection molding products, such as plastic casings and precision electronic component casings, excessive grasping force can easily damage them. On the other hand, if the grasping force is too small, the product may fall during the process of taking the parts, resulting in breaking.

Too fast: the manipulator moves too fast when picking up parts, which will produce a large inertial impact. When the manipulator comes into contact with the product or stops suddenly during handling, this impact force may damage the internal structure of the product, or cause relative sliding between the product and the fixture of the manipulator, thus scratching the surface of the product.

Inaccurate positioning: the positioning accuracy of the manipulator directly affects the picking effect. If the positioning is not accurate, the manipulator may not be able to grasp the product accurately, which will lead to the deviation of the grasping position and the uneven stress on the product and damage it. Or when the product is placed in the designated position, it deviates and collides with other objects, resulting in product damage.

Fixture problem: the shape and size of the fixture do not match the product, and the product can not be held tightly evenly, which will cause the product to be damaged due to excessive local stress. In addition, the wear and aging of the fixture will also affect its grasping performance, such as the decrease of the clamping force of the fixture and the deformation of the gripper, which may lead to the loosening, slipping or damage of the product during the picking process.

Mold-related factors

Poor demoulding: unreasonable design or failure of demoulding mechanism of the mold, such as uneven distribution of ejector pins and insufficient ejector force, will lead to the product being unable to demould smoothly in the mold. When the manipulator forcibly picks up the parts, it is easy to strain, deform or break the products.

Mold surface problems: If the mold surface is worn, scratched and rusted, the product surface will be damaged during demoulding. When the manipulator picks up the parts, these damaged parts may further deteriorate, resulting in product damage.

Product itself factors

Unreasonable product structure design: there are weak links in the structure of the product itself, such as uneven wall thickness and sharp internal corners. Under the external force of the manipulator, these weak parts are prone to cracking, fracture and other damage phenomena.

Unstable product quality: if the process parameters are unstable during injection molding, the strength and toughness of the product are inconsistent. Some products may be damaged due to poor quality under the normal picking operation of the manipulator.

Other factors

Environmental factors: The temperature and humidity of the production environment change greatly, which may affect the physical properties of the products. For example, in the low temperature environment, the brittleness of plastic products increases, and the manipulator is more likely to be damaged when taking parts.

Equipment failure: the failure of injection molding machine or other peripheral equipment may affect the molding quality of products or the timing of taking parts. If the opening and closing action of the injection molding machine is abnormal, the position of the product in the mold will change, and problems will easily occur when the manipulator takes the parts.