Pneumatic grippers have been used in various industries such as; medical device manufacturing, robotics, laboratory processing, semiconductor manufacturing, sensor manufacturing, bearing manufacturing, plastic molding, injection, pharmaceutical, and biotech vehicular lighting and trim.
What is a Pneumatic Gripper?
A pneumatic gripper is a device that is used to pick & place objects. This robotic gripper uses compressed air to operate its gripper jaws, also known as fingers. Most pneumatic grippers have two or three jaws that are similar to human fingers. These fingers enable the pneumatic robot gripper to grasp, hold and release objects.
Types of Pneumatic Grippers
The parallel gripper, just as the name suggests, moves its fingers parallel to its body. As a result of their straightforward design and installation, a parallel gripper is the most commonly used pneumatic gripper type.
The parallel grippers usually accommodate various dimensions and are capable of handling objects of different shapes and sizes.
An angular gripper radially moves its jaws while opening and closing its fingers around a central pivotal point. The pneumatic angular gripper is usually used in applications where the space available is limited, as the fingers can move up and out of the way.
Angular grippers are suitable for holding large objects with odd shapes.
Two and Three-jaw Pneumatic Grippers
The two-jaw pneumatic gripper is the most commonly used as it provides two mounting locations for the jaws. The jaws move in a synchronic manner while opening and closing towards the central axis of the gripper.
On the other hand, the three-jaw grippers are usually used to handle round objects as they provide more gripping force than two-finger grippers.
Magnetic grippers are usually fitted with permanent magnets at their core, making them suitable for handling ferromagnetic objects. Its ability to handle various sizes of items depends on the strength of the electromagnet.
Areas Where Pneumatic Grippers Can be Applied
- Pick & place
- Part handling
- Part ejection
- Part seating
- Oversize loads
- Heavy loads
- Camming and indexing
- Material transfer
- Clamping and fixturing
Pros of Pneumatic Grippers
Among the many benefits of pneumatic grippers, they include:
- Ability to grip various objects
- High gripping force
- Modifiable gripping force
- Easy to implement custom fingers for specific application requirements.
Cons of Pneumatic Grippers
- Partial force and position control capabilities
- Partial variability in the shapes and sizes of objects to be picked
- External valve needed to supply, prep, and control the air.
The Criteria that Should be Applied When Selecting a Pneumatic Gripper
The gripping force is the force that the gripping fingers exert on the workpiece. When selecting a pneumatic gripper, it is advisable to consider that the gripping force can differ depending on the coefficient of friction, air pressure, and gripping conditions between jaws and the workpiece.
Another factor to consider while selecting a pneumatic gripper is the weight of the workpiece. During the operation, the gripping force should be able to support the weight of the workpiece.
Air pressure usually influences the gripper size as it has a direct effect on the gripping force. As such, it is essential to consider the air pressure of a pneumatic gripper when selecting one.
Shape of Workpiece
Another thing to consider is the shape and design of the workpiece. This is because the work piece’s shape will help you determine whether you require a two or three-jaw gripper.
Type of Gripper
When selecting the type of gripper you require, it is also essential to know that grippers can have either internal or external grips depending on the workpiece.
Lastly, pneumatic grippers should be selected based on their operating environment. Grippers are designed differently to operate in different environments. As such, a gripper designed to work in a clean environment may fail to manage harsh environments.
In a manufacturing setting with various applications involving picking & placing, part handling, and material transfer, pneumatic grippers are the best to incorporate in the automation processes.