Industrial Robot Arm Manipulator for Load Handling

Automated material handling in metal fabrication has traditionally required either expensive articulated robots or custom gantry systems. The Herochu industrial robot arm manipulator for load handling offers a different approach: a computer-controlled, precision Cartesian manipulator that combines the flexibility of manual guidance with the repeatability of programmed motion. Designed specifically for loading sheet metal onto laser cutting machines, press brakes, and punching centers, this manipulator features integrated sheet separation, automatic braking, and PC-based control.

What distinguishes Herochu’s industrial robot arm manipulator from conventional pneumatic assist devices is its closed-loop motion control. Using rotary encoders on the rotation axis and a linear encoder on the lift axis, the system achieves ±2 mm repeatability – sufficient for placing sheets onto pin tables or magnetic chucks without operator adjustment. This article examines the technical specifications, control architecture, and performance characteristics of the HC-R series.

Control System Architecture

The Herochu industrial robot arm manipulator operates under a Windows-based industrial PC with a 7-inch touch screen. The software supports three modes:

• Manual mode: Operator guides the arm as with a lift assist device; encoders record positions without active correction.

• Semi-automatic mode: After the operator picks a sheet, the manipulator automatically moves to a pre-taught drop position.

• Automatic mode: Full program execution – the manipulator picks from a defined stack location and places onto the machine table, then returns.

The PC communicates with pneumatic solenoid valves via a PLC backplane. For the rotation axis (HC-R models have ±60-degree rotation, not continuous 360), an electropneumatic servo valve enables speed control from 2 to 5 degrees per second. The lift axis uses a proportional valve for smooth acceleration, achieving lifting speeds of 1 to 5.5 m/min.

Sheet separation function: A critical feature for thin sheet handling. When the manipulator picks a sheet less than 3 mm thick, the system activates a pneumatic nozzle array that blasts air between the picked sheet and the next one. Alternatively, a mechanical tapper strikes the edge of the stack. Both methods break the vacuum seal caused by oil films or static electricity, preventing double feeding.

Technical Parameter Table

Note: The rotation axis is not a full 360° continuous rotation but a ±60° oscillating motion, which is sufficient for most loading applications where the material source and destination are within a 120° arc.

Automatic Braking System

Safety in an industrial robot arm manipulator goes beyond passive protection. Herochu integrates an automatic braking system on both the rotation and lift axes. When the PC detects any of the following conditions, brakes engage within 50 milliseconds:

• Loss of position feedback (encoder failure)

• Excess speed beyond programmed limit

• Operator pressing emergency stop

• Air pressure below 4.5 bar

The brakes are spring-applied, electrically released. In a power outage, the springs clamp the axes, stopping all motion. Additionally, the manipulator includes soft limits programmed into the control software; the arm cannot physically travel beyond these points because end stops provide mechanical backup.

Programming and Operation

Teaching positions on the Herochu industrial robot arm manipulator is straightforward:

1. Switch to manual mode and use the pendant to move the suction head to the desired pick position.

2. Press “Record Pick” – the software stores the coordinates (rotation angle, lift height).

3. Move the arm to the drop position on the laser cutting machine.

4. Press “Record Drop”.

5. Set speed, vacuum delay, and blow-off time parameters.

6. Test the cycle.

For shops running repetitive jobs (e.g., cutting the same sheet size every day), the manipulator can store up to 50 programs. Each program includes acceleration profiles, vacuum thresholds, and sheet separation timing.

Load Handling Performance

The industrial robot arm manipulator excels in two scenarios:

High-mix, low-volume: Job shops that change sheet sizes several times per shift benefit from the manipulator’s quick teach-in (under 2 minutes per new position). No tooling change is required for different sheet dimensions within the capacity range – the suction cup array covers the entire field.

Thin material processing: For 0.8 mm to 2 mm stainless steel, the sheet separation function reliably prevents double picks, which could otherwise cause laser cutter collisions or damaged nozzles. Testing by Herochu showed a double-pick rate of 0.3% with separation active versus 12% without.

Energy Efficiency

Unlike traditional industrial robots that consume 3-5 kW continuously, Herochu’s manipulator uses compressed air for motion and only 50W for the PC and sensors. The vacuum generation (via venturi) operates only when the suction cups contact a sheet. During the move phase, the manipulator holds vacuum using a check valve without consuming air. This makes the system suitable for facilities with limited electrical capacity or those prioritizing energy reduction.

Integration with Laser Cutting Machines

Herochu designed the HC-R series specifically for laser cutting machine feeding. The ±2 mm repeatability aligns sheets within the typical beam offset tolerance of fiber lasers. For machines with automatic pallet changers, the manipulator can be programmed to load pallets offline while the laser cuts. Additionally, the PC control interface includes an I/O relay that communicates “load complete” signals to the laser’s PLC, enabling synchronized operation.

Maintenance and Support

Regular maintenance of the industrial robot arm manipulator includes:

• Monthly: Check encoder belt tension on rotation axis.

• Quarterly: Calibrate vacuum sensor using a digital gauge.

• Annually: Replace suction cups if cracked.

Herochu provides remote diagnostics via the PC’s internet connection. A support technician can view the manipulator’s program, axis positions, and error logs to troubleshoot without a site visit. Spare parts (encoders, valves, cups) are stocked for 10 years after product discontinuation.

Conclusion

The Herochu industrial robot arm manipulator for load handling bridges the gap between purely manual lift assists and full-scale articulated robots. With ±2 mm repeatability, automatic sheet separation, PC-controlled programmability, and a robust automatic braking system, it delivers automated precision handling for sheets up to 500 kg. Shops moving from manual to semi-automated loading will find the HC-R series a logical upgrade – improving consistency, reducing scrap from misaligned sheets, and freeing operators for other tasks. The combination of lightweight aluminum construction and energy-efficient pneumatic actuation makes this manipulator a cost-effective entry into Industry 4.0 material handling.