Robotic End-Of-Arm Tool for Rivet Nut Installation

The robotic end-of-arm tooling is available in different versions. Thus, other types of fasteners can be processed:

A230-CP robotic clinch nut installation tool (2).

• Parallel Drive (patented) with 80kN press-in force for efficient tool movements and low wear
• Active tolerance compensation system (patented)

A230-BI-R robotic blind rivet installation tool (3)

• Process-safe setting of blind rivets / breakaway rivets
• Process monitoring with force-displacement evaluation

A230-SN robotic installation tool for screws and nuts (4)

• Automatic screwdriver with high flexibility
• Also suitable for thread forming screws and threaded inserts

Step 1 - Automatic loading

The blind rivet nut is transported into the loading head via a shot hose. A sensor registers the blind rivet nut and the gripper jaws close.

The gripper holds the blind rivet nut, moves out and the pulling mandrel spindles into the blind rivet nut. The gripper opens and moves back. The setting unit moves into the working position. The fastener is now in the setting position. The setting head indicates "Ready to set" and waits for a setting request.

Step 2 - Feeding the blind rivet nut into the component

The robot moves to the component and inserts the blind rivet nut into the prepared pilot hole using the end-of-arm tool. Before the setting process, the displacement measuring system checks whether the blind rivet nut has been completely fed into the component. The system waits for the external start signal to begin the setting process.

Step 3 - Process-monitored setting operation

The setting process is divided into the pre-stroke and setting stroke steps.

Pre-stroke - The mandrel pulls the blind rivet nut at low pressure without deforming it. As soon as the pre-stroke pressure has been reached and the mandrel no longer moves, the pre-stroke is considered to be completed. The pre-stroke distance is checked.

Setting stroke - The fastener is pulled with a predefined setting pressure, the blind rivet nut is caulked in the component. The setting stroke is considered to be completed when the setting stroke pressure is reached and the blind rivet nut no longer deforms. A force-displacement evaluation is then performed and the setting result "OK" or "Not OK" (NOK) is issued.

The end effector is attached to the robot flange via an adapter plate. It already includes part of the electrics and pneumatics. An additional pneumatic control cabinet contains the remaining electrics and pneumatics, as well as a hydropneumatic pressure intensifier. The control cabinet is placed near the setting unit and fastened to the floor. The blind rivet fasteners are fed via a separate feeding system. The blind rivet fasteners are transported into the end-of-arm tool by compressed air via a shot hose.

Supply connections

1. Control and power supply - from the feeding system to the pneumatic control cabinet

2. Control and power supply - from the robot work cell to the feeding system

3. Pneumatic supply / compressed air

4. Supply line from the pneumatic control cabinet to the end-of-arm tool - Control, electrical power, pneumatics and hydraulics.

The connection between the pneumatic control cabinet and the end-of-arm tool is provided by a multifunctional hose. The hydraulic hose is routed separately. If the system is connected via a robot, a separate robotic energy chain is required into which the supply lines are integrated. The maximum length of the supply lines should not exceed 8 meters.

Nose kit (with mandrel) (1)

Floating mounting of the blind rivet fastener with an active, patented tolerance compensation system.

Loading head (2)

The loading head supplies the lifting unit with fasteners. It includes a gripper that requests the blind rivet fastener at the feeding system and then transfers it to the nose kit.

Pneumatic motor (3)

The pneumatic motor is used to spindle up and down the fasteners. A pressure gauge is used to regulate the pressure during spindling.

Pressure booster (4)

The pressure booster builds up the hydraulic pressure required for pressing.

Pressure regulating valve (5)

The pressure control valve regulates the required pneumatic pressure to the pressure booster. This is used to achieve the required setting force at the setting head. In addition, the valve regulates the pressure of the cylinder so that counterpressure or overpressure is possible.

E / A modules (6)

The digital modules are used to record the cylinder sensors and other sensors, and the analog modules are used to record the displacement measurement data.

Process monitoring

The successful setting process is monitored via the end position query of the infeed and the final pressure in the hydraulic system. The measurement of the final pressure is achieved via the pressure sensor on the hydraulic cylinder.

Force-displacement evaluation

In addition, a process evaluation is possible via the software of the controller module. Here, a force-displacement curve of the entire setting process is recorded and evaluated. With the curve monitoring window function, a successful setting process is set as a reference. As soon as another setting process matches the reference values, it is evaluated as successful.

Overpressing the setting head

When placing the setting head on the component, the setting head is slightly overpressed. This ensures that the fastener is in optimum contact with the component before the setting process begins.

Pre-stroke before setting the blind rivet nut

In contrast to competitive products, our robotic automation system checks whether the blind rivet nut has been completely spindled onto the mandrel before the setting stroke is activated. The advantage - the pressing path is thus traceable for process monitoring. In addition, the component is not damaged if it is not completely spindled on during the setting process.

Operating air pressure
Electrical power supply
Setting stroke max.
Setting force max. (version "standard" / "strong")
Effective line length from end-of-arm tool to pressure amplifier unit
Noise emissions
Interface connection

Cycle time
Reference - blind rivet nut M6, hexagonal, height 16 mm, aluminum; shot-tube length: 5 m
Cycle time (total cycle time including robot positioning)
Setting time (total robot positioning time - robot must not move)
Loading time (time for robot to move - difference between cycle and setting time)

Dimensions (L x W x H)
End-of-arm tool
Pneumatic control cabinet

Weight
End-of-arm tool
Transport weight incl. control cabinet

6 bar
24 V / DC
7 mm
22 kN / 45 kN
max. 8 m
approx. 78 dB(A)
Profinet (standard), Profibus, EtherNet/IP, DeviceNet

 
 
5.12 s
2.93 s
2.19 s

 
approx. 900 x 170 x 350 mm
approx. 702 x 287 x 1113 mm

 
approx. 25 kg
approx. 100 kg