Based on the application characteristics of the cylinder in terms of dynamic characteristics or spatial layout, when we actually select the cylinder, we first determine a suitable category from three aspects: functional requirements, space requirements, and precision requirements.
Choice of cylinder type
Correctly select the type of cylinder according to the working requirements and conditions. If the cylinder is required to reach the end of the stroke without impact phenomenon and impact noise, a buffer cylinder should be selected; if light weight is required, a light cylinder should be selected; if a narrow installation space and a short stroke are required, a thin cylinder can be selected; if there is lateral load, a guide rod cylinder can be selected; If high braking accuracy is required, a locking cylinder should be selected; if the piston rod is not allowed to rotate, a cylinder with the rod non-rotation function can be selected; a heat-resistant cylinder should be selected in a high temperature environment; a corrosion-resistant cylinder should be selected in a corrosive environment; if there is dust, etc. In harsh environments, it is necessary to install a dust cover on the extended end of the piston rod; if no pollution is required, an oil-free or oil-free lubricating cylinder should be used.
It depends on the installation location, purpose of use and other factors. In general, a fixed cylinder is used, and a rotary cylinder should be selected when continuous rotation with the working mechanism (such as lathes, grinders, etc.) is required. When the piston rod is required to perform arc swing in addition to linear motion, the shaft pin cylinder is selected. When there are special requirements, the corresponding special cylinder should be selected.
magnitude of force
That is, the choice of cylinder diameter. According to the size of the load force, the thrust and pull force output by the cylinder are determined. Generally, the cylinder force required by the theoretical balance condition of the external load is selected, and different load rates are selected according to different speeds, so that the cylinder output force has a margin. If the cylinder diameter is too small, the output force is not enough, but if the cylinder diameter is too large, the equipment is bulky, the cost is increased, and the air consumption is increased. In the design of the fixture, the force expansion mechanism should be used as much as possible to reduce the overall size of the cylinder. Among them, P1--cylinder thrust, P2--cylinder pull.
It is related to the use occasion and the stroke of the mechanism, but generally do not choose the full stroke to prevent the piston and the cylinder head from colliding. If it is used for clamping mechanism, etc., an allowance of 10-20mm should be added according to the calculated stroke.