What is a pneumatic gripper?

A pneumatic gripper is an end-effector that uses compressed air to power the opening and closing of gripper jaws or "fingers" to grasp objects. 

They are very commonly used on Industrial robots and automation systems for handling a wide variety of parts and materials in manufacturing.

You’ll see pneumatic grippers providing a few important advantages:

• Lightweight and compact size compared to electric grippers.
• Simple design with few moving parts, which makes them robust and reliable.
• The gripping force can be easily adjusted by changing the air pressure.
• High gripping forces can be generated even in small grippers.
• Low cost compared to other gripper types.
• The gripping force comes from air pressure pushing against an internal piston or diaphragm that is connected to the gripper jaws. Sending compressed air into the gripper extends the piston, opening the jaws. Venting the air allows the piston to retract and close the jaws.
• Grippers come in a variety of designs but parallel jaw grippers are by far the most common. The opening and closing are done in a straight line which is suitable for most applications.
• Options like auto-compensation for off-center loads let pneumatic grippers securely grab irregularly shaped objects, while integrated sensors provide feedback on the grip status.

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What to look for in a pneumatic gripper

When you’re shopping around for a pneumatic gripper for your Industrial robot, there are several factors to keep in mind.

They are: 

• Gripping force - This is one of the most important specifications. You have to make sure the gripper has enough force to securely grip your workpieces without damaging them. The typical pneumatic grippers offer 10 to over 500 pounds of gripping force.
• Stroke length - The stroke length determines how wide the gripper can open. You'll want an adequate stroke to accommodate the size of parts you need to handle. Stroke lengths range from less than an inch to over 4 inches for larger parts.
• Weight capacity - Keep in mind the weight of the parts you need to lift, and choose a gripper rated to handle that load safely. Also, factor in the weight of the gripper itself when determining total payload capacity.
• Integrated sensors - Many pneumatic grippers have built-in sensors to detect when an object is securely gripped and send feedback signals to the robot controller. This allows more intelligent automated processing.
• Tool changers - If you want quick changeover between different end-effectors, you need to look for grippers with tool changer mounts compatible with your robot arm.
• Compressed air requirements - Make sure your compressed air supply can provide adequate pressure and flow for gripper operation. Most pneumatic grippers typically require 40 to 100 PSI supplied through a 6mm airline.
• Control options - Choose a gripper that interfaces easily with your robot controller, which allows direct control of grip and release actions from your robot programs.

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How to integrate a pneumatic gripper with your bot

Now, while we all want everything to be plug and play these days, reality will often beg to differ. So, before you start trying to force your pneumatic gripper onto your robot as if it were an old video game cartridge, hear us out.

Follow these steps:

• The first step is to determine how you'll provide compressed air to power the pneumatic gripper. Most Industrial robots don't have built-in compressed air, so you'll likely need an external air compressor. Make sure to size it appropriately to meet the gripper's air consumption needs.
• Next, decide how the air lines will connect to your robot. Look for a universal pneumatic connector on your robot, like an M4 or M8 fitting. Or see if the gripper manufacturer offers an adapter made specifically for your robot model.
• You'll also need to run an air line from the compressor to the robot workcell. Use flexible pneumatic tubing rated for the required pressure level. Also, make sure the runs aren't overly long to avoid pressure drops.
• On the control side, you'll need to integrate the gripper with your robot programming software. Most models provide digital I/O to open and close the jaws. Or,  some grippers offer plug-and-play kits for popular robot brands.
• For added functionality, look for grippers with built-in force or position sensors. This allows force-controlled grasping to handle delicate items. Make sure your software supports reading these sensor values, though!
• If you plan on switching between multiple grippers, keep in mind adding a quick-change pneumatic tool changer. This allows the robot to automatically swap grippers with no manual reconnecting of airlines.
• Last but not least, test for air leaks on initial setup. Include filtration to remove moisture and particles that could damage the gripper over time. Proper pneumatic integration will maximize uptime and performance.

Top 5 pneumatic grippers for Industrial robots

We’ve scoured the internet, and here’s our rundown for the top 5 pneumatic grippers for Industrial robots so you don’t have to waste half of your day tracking down the best options.

They are: 

OnRobot VGP20

This versatile electric gripper has a payload of up to 20 kg and is programmable for advanced gripping applications. It can handle a wide variety of objects without changing the fingertips, saving you time. The VGP20 connects easily to most robots with a quick-connect electrical interface.

Price: Starting from $6,250.

Robotiq 3-Finger Adaptive Gripper

With flexible rubber fingertips modeled after the human hand, this gripper automatically adapts to handle various shapes and sizes. It has a payload of up to 10 kg. The Robotiq gripper attaches to your robot arm with a plug-and-play USB connection.

Price: Starting from $9,995, which may vary depending on finger material and options.

Piab Kenos Vacuum Grippers

If you need to handle delicate items or porous materials like cloth, a vacuum gripper is a great option. Piab makes high-quality vacuum grippers with payloads of up to 150 kg. They attach to your robot via compressed air and electric connections.

Price: Expect a range from $3,000 for basic models to $8,500+ for high-payload options.

Schunk EGP 40 Gripper

This compact electric parallel gripper has 40N of gripping force, with options to go up to 800N. It has a durable full metal body and attaches to your robot with integrated air tubing and electric cabling.

Price: Starting from $2,800, which can be higher based on higher gripping force options.

Zimmer ERD-E-PS Gripper

With pneumatic parallel jaws, this gripper has up to 250N of force. It has a slim design to fit into tight spaces. The ERD-E-PS connects via an air hose and electric cable built into the housing.

Price: Starting from $2,900 (USD) which can change depending on jaw size and additional features.

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Summing up

We’re confident that, depending on your needs, any of these top 5 pneumatic grippers will take your Industrial robot to the next level. 

But don't forget to factor in all the variables like required grip force, duty cycle, and integration with your existing robot before you make a purchase!

Don't be afraid to reach out to the manufacturer if you need help selecting the optimal gripper configuration. It’s better to spend some time sorting out your questions than having to spend time returning a costly product!

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FAQs

How do I provide compressed air to a pneumatic gripper?

You'll need to run an air line from your compressed air source to the gripper. Use a flexible pneumatic air line rated for your air pressure. Connect it to the gripper's air inlet fitting – make sure to use thread sealant.

What PSI do pneumatic grippers need?

Most pneumatic grippers operate at 80-100 PSI. But double-check the specifications for your specific gripper model. Operating below the recommended PSI can zap the overall gripping force.

How do I control a pneumatic gripper?

You'll need a way to turn the compressed air on and off. Solenoid valves connected to your robot controller are commonly used. The valve directs air to the gripper when you want it to close and releases air pressure to open it.

What mounting options are there?

Grippers can have tapped mounting holes or through holes for bolting to your robot. Some also have adapters available for easy mounting to robot arms.

How do I know if a gripper will work with my robot?

Check with the robot and gripper manufacturers. See if they have an integration or recommend specific models known to work well together.

Can I Use a pneumatic gripper for delicate objects?

Yes, you can! While many pneumatic grippers are known for vise grip, several are designed for gentle handling of delicate objects. These specialized grippers often use:

• Soft gripper pads: Made from silicone, foam, or other flexible materials, these pads conform to the object's shape without applying excessive pressure.
• Adjustable gripping force: You can fine-tune the air pressure to achieve the optimal gripping strength for your delicate object.
• Precise control valves: These valves allow for gradual opening and closing of the gripper, minimizing jerking motions that could damage fragile items.

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Next steps

If you're in search of the ideal robot arm and end-effector setup tailored to your requirements, check out  RO1 from Standard Bots. 

This model is not only versatile with its range of pneumatic gripper options but also features universal M8 connectors and compatibility with OnRobot end-effectors. It's a perfect fit for both expansive and compact machine shops:

• Value-oriented: The RO1 is notably the most cost-effective choice in its class. Its pricing is substantially more affordable than other leading brands, starting at just half the cost of its closest competitor.
• Superior vision technology: Outfitted with advanced vision systems, the RO1 streamlines operations with intuitive, no-code programming. This allows for the precise detection of even minuscule defects.
• Safety-focused design: With integrated safety sensors and collision detection, the RO1 prioritizes safe operation, enhancing the security of your workspace.

Talk to  our team of experts for a no-cost, 30-day trial on-site. Our specialists are ready to provide you with the insights and guidance needed to effectively launch your initial robotic setup.