Introduction of Flexible Tooling Fixture's gripper

The flexible Tooling Fixture's gripper is a device that grips and manipulates an object. It is capable of holding and releasing objects while performing specific actions. Motion devices often mimic the motion of the human body and, in the case of grippers, the motion of the fingers. The "fingers" themselves are not part of the gripper. They are special custom tools called "grippers" used to hold objects.

The Flexible Tooling Fixture manufacturer describes two main types of gripping actions.

External clamping: This is the most common method of clamping objects and is the simplest, and requires the shortest stroke length. The clamping force exerted by the gripper will hold the object when the gripper tabs are closed.

Internal clamping: In some applications, the object needs to be clamped from the center due to the geometry of the object or due to the need to be close to the outside of the object. In this case, the gripper clamps the object with an expansion force.

Principle of operation

The pneumatic gripper is the most widely used Flexible Tooling Fixture gripper; it is essentially a cylinder powered by compressed air. When supplied with air, the gripper blade will approach the object and hold it firmly enough to perform other operations, and when the direction of the air changes, the gripper will release the object. Typical applications are to change the direction of the object or to move the object during a pick-and-place operation.

When the gripper holds the workpiece, it should have special force and shape constraints to ensure that the clamped workpiece is released entirely during movement, dwell, and loading. In addition, it should ensure that the geometric deviation of the workpiece clamping posture reproduction is within the given tolerance band.

Types and characteristics

Mechanical grippers are often used with compressed air as the power source, and the drive mechanism realizes the movement of the fingers. According to the different trajectories of the fingers when clamping the workpiece, mechanical grippers are divided into.

(1) Circular arc opening and closing type driven by the transmission mechanism, the trajectory of the finger end is a circular arc. This type of gripper has strict requirements on the size of the clamped part. Otherwise, it may cause the workpiece to be out of shape.

Arc-parallel opening and closing type

(2) Arc-parallel opening and closing type This type of gripper works with two fingers for equal opening and closing motion, and the trajectory of the finger end is a circular arc. The gripper is the two cases of similar opening and closing of the fingers driven by the parallelogram drive mechanism, where the mechanism shown in the clamping finger end forward and the mechanism shown in the clamping finger end backward.

Linear parallel opening and closing type

(3) Linear parallel opening and closing type The trajectory of the two fingers of this type of gripper is straight, and the gripping surface of the two fingers is always kept nearly equal. The cam mechanism is used to realize the parallel opening and closing of the two fingers, and the sliding block of each finger is equipped with an oblique cam slot. When the piston rod moves up and down, the roller installed at the end of it moves in the cam slot to realize the parallel clamping motion of the fingers. The rack and pinion mechanism is adopted. When the rack at the end of the piston rod drives the gear to rotate, the rack on the fingers makes a linear motion so that the two fingers open and close equally to grip the workpiece.