The sheet is fixed on the clamping device. Universal vacuum forming machine and composite thermoform machine, multi-easy clamping device fixed size sheet. Plenty of whole molding machine with a clamping frame.
Clamping device can be divided into two categories: one is the frame, and the other is the split- The frame-type clamping device is composed of upper and lower two frameworks. The sheet is sandwiched between the two frameworks. When the frame is opened, the lower frame is generally to maintain the fixed state. The lower portion of the framework on the various types of single-station forming machine is fixed directly in the molding chamber.
Installed parison and finished out the manual and semi-automatic molding machine by hand, when the frame size is large, and are equipped with the safe operation of the device within the framework of open. The molded parison slip greater the required clamping force can be adjusted within a relatively wide range, for this end, the use of the rubber roller of the two packages, with a spring pressed against each other, and are equipped with a pressure regulating means. Continuous tab molding machine clamping both sides of the zipper together with front and rear gates. The best clamping device with automatic control, with a view to action quickly, can help improve part quality and efficiency.
The vacuum thermoforms the plastic process of the thermoplastic sheet and film, and the main step is one of the sheets was heated to soften the sheet into the plasticity of the device. The distance between the duration and quality of the electrically heated depends on the structure of the heater, the heat transfer of thermal inertia of the temperature after the radiation surface, the sheet with the heater, radiant energy absorption coefficient, and the characteristics and thermal physical properties of the material of the surface of the heater. The conventional heater with an electric heater, a crystal radiator and an infrared heater.
The vacuum system consists of pumps, cylinders, valves, piping, and a vacuum table, often in a vacuum molding using a separate models vacuum pump, such pumps, the degree of vacuum should be 0.07 ~ 0.09 Mpa (520mmHg) above. The cylinders are generally thin steel plate welded cylindrical casing, a bottom is elliptical. The accumulator tank capacity should be at least half as large as the largest capacity of the molding chamber. The vacuum pipeline must be equipped with appropriate valves to control the vacuum narrow capacity. The rotational power of the vacuum pump is determined by the size of the molding apparatus and the molding speed, the larger or faster molding equipment commonly used to 2 ~ 4KW. Vacuum the size of the central system, as factory production and the development of specific requirements.
Pneumatic system by thermoforming machine with its own compressor, air tank, the workshop supervisor Road set, valves, and other components. Molding machine requires compressed air, pressure 0.6 ~ 0.7MPa various vacuum forming machine is widely used piston air compressors. You can also supply large screw-type air compressors throughout the whole plant. Compressed air in addition to a large number of outside in molding, as well as for stripping, early products outside cooling and power manipulation the mold framework and operation sheet mechanical action.
In order to improve production efficiency, vacuum thermoform products Stripping often need cooling. The ideal situation is the inner and outer surfaces of the parts in contact with the mold is cooled, preferably with built-in cooling coils mold. For non-metallic molds, such as wood, plaster, glass fiber reinforced plastic, epoxy mold can switch to air-cooled, not water-cooled, and plus a water mist to cool the outer surface of the vacuum forming parts. Production using natural cooling can be obtained annealing workpieces, is conducive to improve the impact resistance of workpieces. Cooled with water, although the production efficiency is high, but the workpiece internal stress.
Releasing the article out of the injection mold, usually either the mold or punch, the majority of occasions securement mold is due to the shrinkage of the article to cool, so the vacuum suction holes or hair so that the opposite direction releasing. Especially for the stripping slope mold or die while stripping mechanism contradicts or shock.
The control system including instruments, pipes, valves, various parameters and actions generally include vacuum thermoforming plastic molding, finishing process control. Control mode is manual, electrical – mechanical automatic control, computer control, the specific choice considering the initial investment in labor costs, technical requirements, the cost of raw materials, production and maintenance costs and other factors.