Pneumatic grippers

Gripper systems

Gripper systems are indispensable for industrial robots or handling systems as they form the connection between the workpiece and the handling system. Grippers are operated pneumatically or electrically and are used for gripping, holding, positioning and orienting the workpiece or tool. Normally, gripper systems are mounted on the outermost or last axis of handling systems and are connected to the main power cable.

Different functionalities of gripper systems

Gripper systems can have different functionalities. They operate mechanically, pneumatically, electrically or adhesively.

Mechanical grippers resemble a human hand and have one or more fingers. These gripper systems can have several rigid joints, but are usually also flexible and bendable. They are usually pneumatic, i.e. they are operated by compressed air. Mechanical or electrical actuation is also possible.

Pneumatic grippers have vacuum cups or suction cups that pick up the workpiece using suction in order to transport it for further processing. In addition to vacuum technology, the workpieces to be processed can also be clamped and moved using pressure. If pneumatic grippers cannot be used because the surface of the workpiece does not permit the creation of a vacuum, e.g. if it is porous or holey, adhesive gripper systems usually provide an alternative solution.

When their gripping surfaces, which have tiny hairs, are pressed onto a workpiece, Van der Waals forces are generated that can be used to lift the workpiece. If the adhesive gripper is slightly tilted sideways with control, it releases its grip again. The advantage of adhesive grippers is that they do not require power and are therefore extremely energy efficient.

Electric grippers with magnetic function attract and hold the workpiece magnetically. A distinction is made between two types of magnetic gripper systems: permanent magnet grippers and electromagnetic grippers. Once the workpiece has been lifted by a gripper with permanent magnet, it must be removed by another system. Electromagnetic grippers are switched on and off by electrical energy, which is why workpieces can be gripped and set down again easily.

Mechanical grippers from Festo

Mechanical grippers from Festo are moved by an internal drive and transform the drive motion into a gripping motion. This movement of the gripper jaws is referred to as a stroke. Depending on the stroke and gripping force, workpieces of different sizes can be gripped and handled. Grippers with a long stroke are offered by Festo in both pneumatic and electric versions.

Find out more

Parallel grippers

Festo offers mechanical parallel grippers in various designs. They are suitable for internal and external gripping. Parallel standard grippers are used for handling a wide range of small parts in a clean environment. To absorb high forces, Festo offers sturdy gripper systems with a resilient T-slot guide for the gripper jaws. Sealed grippers are suitable for handling tasks in very dirty and demanding environments. The precise parallel gripper has gripper jaws with an impressive backlash-free roller bearing.

In our Core Range you will find the three parallel grippers DHPC, DHPS, HGPL and HGPT in a wide range of sizes. DHPC and DHPS are characterised by their high gripping force, compact design as well as maximum repeat accuracy, while HGPL is particularly suitable for use with large workpieces and long strokes. The parallel gripper HGPT is sturdy, powerful and, like the HGPL, has a T-slot guide. In addition to our Core Range, you will find additional parallel grippers for a wide variety of requirements at Festo. These include products that are ideal for gripping larger workpieces, self-centring grippers and grippers for very harsh environments as well as micro grippers with an extremely small and convenient design.

Parallel grippers

Three-point grippers

With three-point grippers, a workpiece can be picked up centrally. At Festo you will find three-point grippers in various designs. Standard three-point grippers are suitable for the universal handling of small parts in a clean environment. To absorb high forces, the three-finger gripper systems with resilient T-slot guide are used for internal and external gripping. Sealed three-point grippers are suitable for handling tasks in very dirty and demanding environments.

Our three-point gripper DHDS ensures maximum repeat accuracy and has a high gripping force while also having a compact design. The Festo three-point gripper HGDD enables precise gripping with centric movements despite high torque loads and is particularly suitable for use in very harsh environments. The gripper jaw guide of the three-point gripper HGDT is protected from dust by sealing air, which makes this gripper particularly durable. It is also available as a high-force version and enables the gripper jaws to be moved synchronously.

Three finger grippers

Angle grippers

Angle grippers from Festo are available as small parts grippers and micro grippers. Each jaw of the angle gripper opens up to 20°. The opening angle can eliminate the need to approach an object from the side. The specific opening angle can reduce cycle times and interfering contours can be avoided.

Our latest model, the angle gripper DHWC, can be used either as a double-acting or single-acting gripper. In addition, the gripper jaws are supported laterally and thus the gripper has a high torque load. The angle gripper DHWS with improved gripper jaw guide has an internal fixed restrictor, which makes an external restrictor superfluous in most of the applications. The Festo angle gripper HGWM is characterised by its small and convenient design. The externally adaptable gripping fingers make it very versatile.

Angular grippers

Radial grippers

Radial grippers from Festo are available in two variants. The standard radial gripper is available as a small parts gripper for clean ambient conditions. A robust version with a sealing air connection allows higher forces to be absorbed. Each jaw of the radial gripper opens up to 90°. The wide opening angle may make it unnecessary to approach an object from the side.

The radial grippers DHRC and DHRS from Festo with their lateral gripper jaw support enable a high torque load. The former can be used either as a double-acting or single-acting gripper, the latter is sturdy and has an internal restrictor. Characteristic for the radial gripper HGRT is the precise and sturdy kinematics for very high torque absorption as well as the long service life.

Radial grippers

Swivel/gripper unit

The swivel/gripper unit, a compact functional combination of parallel gripper and swivel unit, is also part of the group of mechanical gripper systems. Both functions can be controlled and moved individually and independently of each other. The swivel/gripper unit is available in three different sizes. The swivel angle can be adjusted from 0° to 210° at a maximum gripping force of 192 newtons.

You can get the swivel/gripper unit HGDS from Festo, with a swivel angle that can be infinitely adjusted and which guarantees a precise end stop with elastic cushioning or integrated shock absorber.

Swivel/gripper units

Pneumatic grippers from Festo

As part of the range of pneumatic gripper systems, you will find reliable internal grippers in the shape of bellows grippers that are gentle on components. As the bellows diameter is increased mechanically, the load is gripped using its inner contour. Bellows grippers are suitable for gripping and transporting parts with a circular opening, such as glasses, cups or bottles. There are two different bellows materials: EPDM is suitable for high loads and silicone for high temperatures.

The Festo bellows gripper DHEB is available in 11 sizes for gripping diameters from 8 to 85 mm. The DHEB moves either up or down. Adaptive shape gripper DHEF is suitable for gripping parts with undefined positions and shapes as well as products with different geometries.

Bellows grippers

Accessories for gripper systems

Of course, you will also find suitable accessories for your gripper systems at Festo, including various gripper jaws, solutions for stroke reduction, adapters for grippers, gripper jaw blanks and adaptive gripper fingers.

Accessories for grippers

What are pneumatic grippers?

Pneumatic grippers are mechanical devices that are used to grip and hold objects using compressed air. Pneumatic grippers are commonly used in industrial automation applications, such as in manufacturing and assembly lines, to manipulate and transport objects.

Pneumatic grippers typically consist of two or more gripper jaws, called fingers also, that are operated by a piston or a rotary actuator. When compressed air is supplied to the pneumatic gripper, the jaws move toward each other to grip the object. When the air pressure is released, the jaws return to their original position, releasing the object.

Pneumatic grippers come in a variety of sizes and configurations to accommodate different types and sizes of objects. Pneumatic grippers can be designed to grip objects with parallel or angular jaws, and they can be equipped with sensors to detect the presence of an object or to provide feedback on the gripping force.

One of the advantages of pneumatic grippers is their speed and efficiency. Because they are powered by compressed air, pneumatic grippers can operate quickly and reliably, making them ideal for high-speed applications. Pneumatic grippers are also relatively low-cost and easy to maintain.

Key parts of a pneumatic gripper:

  • Body: The body of the gripper is the main structural component that houses the other parts of the gripper and provides a mounting surface for the gripper.
  • Jaws or gripper fingers: The jaws or gripper fingers are the parts that actually make contact with the object being held. They can be straight or curved, with flat or serrated surfaces, and can be designed with a range of gripping forces and opening widths.
  • Actuator: The actuator is the part of the gripper that controls the movement of the jaws or fingers. This can be a pneumatic cylinder, an electric motor, or a hydraulic system, depending on the type of gripper.
  • Sensors: Grippers may also be equipped with sensors to detect the presence of an object, to measure the gripping force, or to provide feedback on the position of the gripper.
  • Mounting brackets: Mounting brackets are used to attach the gripper to a robot arm or other machinery.
  • Control system: The control system for the gripper can vary depending on the type of gripper and the application. It may include switches, sensors, or a programmable logic controller (PLC) to control the operation of the gripper.

How does a pneumatic gripper work?

A pneumatic gripper works by using compressed air to move the jaws of the gripper and hold an object. The gripper typically consists of a cylinder, piston, and gripper jaws, and is connected to a source of compressed air.

When compressed air is supplied to the cylinder, it pushes the piston, which in turn moves the jaws of the gripper toward each other. The jaws grip the object securely, and the gripper can hold it until the air pressure is released.

Opening force and closing force are two related measures of the gripping force of a gripper.

Opening force refers to the amount of force required to open the jaws or fingers of the gripper and the Closing force, on the other hand, refers to the force that the gripper applies to the object being held when the jaws or fingers are closed.

The opening force of a gripper can be adjusted by changing the air pressure or by adjusting the position of the gripper fingers. Some grippers also have adjustable opening force settings that can be programmed into the gripper control system.

When deciding, which pneumatic gripper is the best option, we need to bare in mind the internal and external clamping. Internal clamping refers to a method of holding a workpiece or tooling component from the inside, using an expanding mandrel or collet while external clamping, on the other hand, refers to a method of holding a workpiece or tooling component from the outside, using an external clamp or collet.

Types of grippers

There are several types of grippers that are commonly used in industrial automation applications. Here are some of the most common types:

  • Parallel grippers: These grippers have two jaws that move parallel to each other to grip the object. They are the most common type of gripper and are used in a wide range of applications including harsh environments.
  • Angular grippers: These grippers have jaws that move at an angle to each other, allowing them to grip objects that are irregularly shaped or difficult to grasp with a parallel gripper.
  • Vacuum grippers: These grippers use suction to grip and hold objects. They are often used in applications where the object being handled is fragile or has a non-uniform shape.
  • Servo-electric grippers: These grippers use an electric motor to actuate the jaws, providing precise control over the gripping force and position.
  • Pneumatic grippers: The pneumatic grippers use compressed air to actuate the jaws. They are simple, reliable, and can operate at high speeds.
  • Magnetic grippers: These grippers use a magnetic field to grip and hold ferromagnetic objects. They are often used in applications where objects need to be picked up and transported quickly and reliably.
  • Hydraulic grippers: These grippers use hydraulic fluid to actuate the jaws. They are often used in heavy-duty applications where high gripping forces are required.

The choice of gripper depends on the specific requirements of the application, such as the different sizes and shape of the object being handled, the required gripping force, and the speed and precision of the gripping operation.

Pneumatic grippers in robotics.

Pneumatic grippers are commonly used in robotics for various applications that require the manipulation and handling of objects. These grippers operate using compressed air or gases to generate the necessary force for grasping and releasing objects.

Here are some key points about pneumatic grippers in robotics:

  • Operation: Pneumatic grippers utilize compressed air or other gases to create mechanical force. This force is usually generated by an air compressor and controlled using pneumatic valves.
  • Design: Pneumatic grippers come in various designs to suit different applications. The most common types are parallel-jaw grippers, which feature two opposing jaws that move in parallel to grip the object. Other designs include angular grippers, three-finger grippers, and custom-made grippers for specialized tasks.
  • Actuation: Pneumatic grippers use pneumatic actuators, such as pneumatic cylinders or pneumatic rotary actuators, to control the opening and closing of the gripper jaws. These actuators convert the air pressure into mechanical motion to perform gripping actions.
  • Force and Control: Pneumatic grippers offer a wide range of gripping forces, depending on the size and type of gripper used. The force can be adjusted by regulating the air pressure supplied to the gripper. Gripper control can be achieved through manual valves, solenoid valves, or more advanced control systems integrated with the robotic controller.
  • Advantages: Pneumatic grippers have several advantages in robotics applications. They are generally lightweight, compact, and provide high gripping forces relative to their size. Pneumatic systems are also relatively simple and cost-effective compared to other types of grippers. They can operate at high speeds and are suitable for applications where a moderate level of precision is required.

Pneumatic gripper from Festo

Festo is a well-known manufacturer of pneumatic components and systems, including pneumatic gripper. Festo offers a range of pneumatic grippers with different designs and features to meet various automation needs. Here are some examples of pneumatic grippers from Festo:

DG pneumatic gripper: Festo's DG series are designed for precise gripping and handling tasks. These grippers feature a compact and lightweight design, making them suitable for use in confined spaces. The DG series grippers come in different sizes and jaw types to accommodate a wide range of object sizes and shapes.

DH pneumatic gripper: The DH series from Festo are angular grippers that provide versatile gripping capabilities. These grippers can grip objects from the side, making them ideal for applications where the object needs to be picked up from an unconventional angle. The DH grippers offer adjustable gripping force and come in various sizes.

EHPS pneumatic gripper: Festo's EHPS series grippers are electrically driven pneumatic parallel grippers. These grippers combine the advantages of both electric and pneumatic systems, offering precise control and high gripping forces. The EHPS grippers are designed for dynamic and demanding applications and feature a compact design.

HGPL pneumatic gripper: Festo's HGPL series grippers are heavy-duty pneumatic parallel grippers suitable for handling large and heavy objects. These grippers are robust and offer high gripping forces. They are designed for applications that require strong gripping capabilities, such as heavy part handling and metalworking processes.

ADH pneumatic gripper: Festo's ADH series grippers are adaptive pneumatic grippers with flexible fingers. These grippers can adapt to various object shapes and sizes, making them suitable for handling objects with irregular or delicate surfaces. The ADH grippers feature compliant fingers that conform to the object's shape, allowing for secure and gentle gripping.