What Is a Clamping Cylinder?
A Clamping Cylinder is a machine with a repetitive motion mechanism that clamps a workpiece for automation in a production line.
A cylinder part, called a rod, moves in a linear motion up and down or left to right to clamp a workpiece during the manufacturing process, usually using hydraulic or pneumatic pressure as the clamping motion source.
Hydraulic or pneumatic pressure is usually used as the clamping motion source. To avoid interfering with machining and spot welding, space-saving measures are taken throughout the machine.
A Clamping Cylinder is important to be able to easily and quickly attach and detach the workpiece at the start and end of machining.
Uses of Clamping Cylinder
Clamping Cylinders are used to clamp workpieces on automated production lines in factories. Mainly, they are used in automated welding lines using industrial robots and in workpiece clamping on machining centers.
To obtain confirmation of clamping as an electrical signal, auto switches are usually installed on the clamping and unclamping sides of the cylinder. However, when used on a welding line, the welding current generates a disturbing magnetic field, which may cause a malfunction with a normal auto switch. By using a strong magnetic field resistant auto switch, it can be used accurately.
Principle of Clamping Cylinder
A Clamping Cylinder is a mechanism that uses pneumatic or hydraulic pressure as a driving source to operate the cylinder body and clamp a workpiece. In a normal clamping cylinder, the forward/reverse movement of the cylinder is converted into a clamping motion by means of a link mechanism, a mechanical mechanism, to clamp the workpiece.
Hydraulic pressure is selected when a particularly strong clamping force is required. However, since hydraulic pressure requires a certain amount of man-hours for equipment maintenance, pneumatic pressure is selected when the clamping force is normal and good. Rotary clamp cylinders have a groove machined into the rod for swiveling, and clamp while swiveling by means of a cam mechanism.
Pin clamp cylinders are driven primarily by pneumatic pressure, but clamp by retracting the clamping arm inside the pin while the pin performs its positioning function. The pin diameter of the pin clamp cylinder is selected according to the hole diameter used for positioning and clamping. Only the pin portion is visible from the top surface in the clamped condition, which minimizes interference with machining and saves space.
Types of Clamping Cylinder
Clamping Cylinders are available in a great variety of types, depending on the application. The most typical types are rotary clamp cylinders and pin clamp cylinders.
1. Rotary Clamp Cylinder
Rotary Clamping Cylinder is a clamping cylinder with a rotating mechanism added to the piston rod. Depending on the application, left-rotation or right-rotation is selectable, but be aware that some types do not allow clamping operation during rotation.
2. Pin Clamp Cylinder
As the name suggests, pin clamp cylinders have a mechanism that uses a pin for clamping, and are mainly used for clamping sheet metal. Therefore, some of them can be optionally equipped with a strong magnetic field resistant auto switch to withstand welding.
Other Information on Clamping Cylinder
Power Source for Driving Clamping Cylinder
One of the recent options for driving power sources for clamping cylinders is the trend toward electrification. Electric power has various advantages, such as the ability to be used without air piping facilities, easy positioning of multiple points, and shock mitigation at the end point, but it has not been widely used due to cost considerations.
However, in recent years, with the spread of electric actuators, electric cylinders that can be used for clamping cylinder applications (compatible with air cylinders) at a reasonable cost are rapidly gaining popularity.
One weak point of electric cylinders is that their clamping force is inferior to that of pneumatic cylinders in the same size comparison, but the fine control and easy positioning provided by the electric actuator have led to their replacement, and this is a trend that deserves attention in the industry.