Custom Transfer Bar Feeder Automation for Stamping Press Line

Custom Transfer Bar Feeder Automation for Stamping Press Line

Project Background

An automotive client operated a tandem stamping press line where parts were manually transferred between presses. This manual process limited production speed and posed safety risks on the shop floor. Ontario Dynamics was tasked with retrofitting this existing line with press line automation – specifically a servo-driven transfer bar feeder system – to automate part transfer without expensive press replacements or extensive modifications. The goal was clear: deliver a low-cost transfer bar system that could meet or exceed the performance of big-name automation vendors, while fitting seamlessly into the client’s current equipment and workflow. By leveraging off-the-shelf components and clever engineering, our team set out to eliminate manual handling, improve cycle time, and ensure a quick, hassle-free integration into the old presses.

Technical Approach

Ontario Dynamics’ approach centered on a custom transfer bar feeder automation solution built from readily available components. We designed a lightweight transfer bar structure using modular aluminum extrusion profiles. This bar spans the distance between press stations and carries the part-handling “fingers” that grip and move stamped parts. Motion is achieved via three coordinated axes (X, Y, and Z), each driven by commercial linear actuators powered by Mitsubishi servo motors. The X-axis shuttles the transfer bar longitudinally from one press to the next, the Y-axis provides in-and-out motion to reach into die areas, and the Z-axis raises/lowers the bar for part pickup and placement. All axes are synchronized through a Mitsubishi PLC controller, which ensures multi-axis motions occur in harmony with the press cycle.

Crucially, we added a custom encoder assembly to the existing mechanical presses to monitor the crankshaft position of each press. This encoder feed allows the PLC to precisely time the feeder’s motions with each press stroke. As the press cycles, the PLC commands the servos to enter the die, grasp the part, and retract just after stamping – transferring the part to the next station exactly when needed. By synchronizing the transfer bar feeder motion with the press stroke in real-time, we achieved seamless integration without requiring any changes to the presses’ core controls. The entire automation sequence is run by the Mitsubishi PLC in a master-slave arrangement with the press: the PLC reads the press encoder and sends coordinated commands to the servo drives, resulting in a smooth, synchronized retrofit stamping automation of the line.

Design Highlights

  • Lightweight Aluminum Transfer Bar: The transfer bar itself was fabricated from high-strength aluminum profile extrusions. This design choice yields a rigid yet lightweight beam, reducing the moving mass. A lighter bar means smaller actuators can be used and faster response with less vibration, all contributing to a more efficient system. The aluminum construction also allows easy modification or extension of the bar for future needs, unlike bulky welded steel structures in conventional systems.
  • Quick-Release Tooling Fingers: We implemented an innovative quick-release, tool-less mounting system for the part-handling fingers on the transfer bar. Each finger – the gripper that holds the stamped part – can be attached or removed in seconds via clamp levers, without any screws or special tools. This user-friendly design makes changeovers extremely fast and simple. The client can reconfigure the feeder for different part shapes or die configurations with minimal downtime, greatly enhancing flexibility on the production line.
  • Off-the-Shelf Linear Actuators: All three axes (horizontal transfer, in/out feed, vertical lift) utilize standard industrial linear actuators driven by servo motors. By selecting robust off-the-shelf actuators, we avoided the need for custom-fabricating complex linkages or cam drives. These actuators come with built-in linear guides and ball screws, providing high precision and load capacity out of the box. They were carefully sized to handle the part weight and press spacing, delivering smooth motion and ±0.2 mm repeatability in positioning. Standard components also mean easy maintenance and readily available spare parts, ensuring long-term serviceability.
  • Pneumatic Counterbalance on Z-Axis: To further optimize the vertical (Z-axis) motion, we integrated pneumatic counterbalance cylinders that support most of the weight of the transfer bar and tooling. By using air pressure to counteract gravity, the Z-axis servo motor sees a much lighter effective load. This allowed us to choose a smaller servo actuator for lifting, reducing cost and energy usage. It also improves responsiveness – the Z-axis can raise and lower faster since it’s not fighting the full weight of the system. The counterbalance system is tuned to offset the mass of the moving components, so the servo essentially only handles the dynamic forces, not the static weight.
  • Mitsubishi PLC and Servo Control: At the heart of the system is a Mitsubishi PLC paired with Mitsubishi servo drives on each axis. This control platform was chosen for its reliability and high-speed motion coordination capabilities. The PLC executes a custom program that handles trajectory generation, acceleration/deceleration profiles, and position feedback for all axes in real time. The Mitsubishi servos are fully synchronized – for example, the X and Z axes move in tandem to extract a part smoothly from the die without collision. The PLC also communicates with the press controls (via the encoder and I/O signals) to interlock the feeder motion with the press timing for safety. Using a single integrated control system for all axes ensured synchronized multi-axis motion and simplified troubleshooting. The operator interface was implemented on a Mitsubishi HMI screen, giving a clear view of status and allowing adjustments to timing or stroke parameters if needed.
  • Minimal Press Modifications: A key requirement was to avoid major changes to the existing presses or the facility layout. Our transfer bar feeder was designed as a compact add-on unit that mounts onto the press line with minimal footprint. Custom brackets were used to attach the linear actuator assemblies to the sides of the presses at existing bolt locations, so no drilling into the press frames was necessary. The entire unit fits within the space between presses, and all wiring was routed cleanly without interfering with other equipment. Aside from installing the encoder on the press crank (a non-intrusive addition), we did not modify the presses’ mechanisms. This minimal-invasiveness preserved the original press setup and allowed the automation to be largely “bolt-on,” a critical factor for the client. It also meant the installation and commissioning could be completed quickly during a short scheduled downtime.

Competitive Edge

Ontario Dynamics delivered a customized, lower-cost alternative to the big-name automation vendors, demonstrating how intelligent design can beat one-size-fits-all solutions. Traditional press transfer systems from big companies tend to be heavy-duty and complex, often designed for brand-new lines or very large presses. For example, a standard 3-axis transfer system uses specialized hardware like helical rack-and-pinion drives, pneumatic bar locking mechanisms, and even vacuum-based end-of-arm tooling. These systems are highly capable but come with a large physical footprint and significant integration overhead. Similarly, one-bar transfer systems can automate multi-press lines (up to 10 presses in sequence) with high-speed servo axes, but such scale and complexity can be overkill for a moderate-size line and require substantial reconfiguration of the press layout and controls.

In contrast, our solution was purpose-built for the client’s specific needs. By using modular components and a lean design, we kept the hardware size and weight to a minimum while still covering the required X/Y/Z motions. The entire transfer bar feeder system has a much smaller footprint than typical commercial transfer robots – it tucks right into the existing line without a dedicated gantry or platform. Fewer custom-machined parts and no redundant features meant a lower overall cost. In fact, the Ontario Dynamics feeder achieved the same core functionality (part pick-and-place between presses with synchronized timing) at a fraction of the price that major OEMs would charge for a full-scale transfer line retrofit.

Integration was also faster and simpler. Large vendor systems often demand new control cabinets, press retrofits, and weeks of on-site integration work by their engineers. Our system, on the other hand, was installed and commissioned by our team in a matter of days, thanks to thorough offline testing and the plug-and-play nature of the off-the-shelf actuators and Mitsubishi control package. The intelligent component selection – using just the right size actuators, adding a counterbalance to avoid oversized motors, choosing a familiar PLC platform – meant the final machine is both efficient and easy to support. The client’s maintenance staff can service the feeder without needing specialized training or expensive proprietary parts.

Another competitive edge is the flexibility of our design. The quick-release finger tooling allows rapid retooling for different parts, which is something not easily achieved in many standard transfer systems that use bolted or welded gripper setups. This gives the client the agility to run new product variants or adjust to design changes with minimal additional investment. In essence, Ontario Dynamics provided a tailor-made automation solution that combines the best of both worlds: the performance of a servo-driven transfer bar system and the agility of a custom-engineered machine, all delivered in a cost-effective package.

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Results

The results of the project were immediately tangible on the production floor. The custom transfer bar feeder successfully automated the part transfer between the stamping presses, eliminating the need for manual handling by operators. This led to improved safety (no more staff working between active presses) and a more consistent, predictable production flow. The line’s throughput increased because the feeder can transfer parts quickly enough to keep up with the presses’ ideal cycle rate – there is no waiting on human operators, and the presses can run continuously in synchronized mode. In fact, the client observed a significant reduction in idle time between stamping operations, effectively boosting overall equipment efficiency.

Equally important, the solution was delivered on budget, costing far less than quotes the client had obtained from larger automation firms for a similar scope. The use of off-the-shelf components and minimal custom fabrication kept costs low. Moreover, because we avoided major modifications to the presses, the client saved on potential re-certification or extended downtime costs. The installation was completed over a short maintenance interval, and full production resumed shortly after with the new automation in place.

The low-cost transfer bar system has now been running reliably, with the Mitsubishi-driven control ensuring accurate and repeatable movements every cycle. Maintenance feedback has been positive – operators find the HMI controls intuitive, and technicians appreciate the straightforward mechanical design when performing routine checks. The quick-release tooling feature has already proven its worth by allowing faster die changes and setup for new parts, contributing to reduced changeover times on the line.

In summary, Ontario Dynamics transformed a manual, labor-intensive process into a highly efficient automated operation. By delivering a servo-driven transfer bar feeder that marries smart engineering with practical component choices, we provided the client with a retrofit stamping automation solution that not only meets their technical requirements but also gives them a competitive edge in production. This case study showcases Ontario Dynamics’ commitment to technical excellence, cost-effective design, and tailored solutions that outperform the “off-the-shelf” offerings of larger competitors – all while maintaining a minimal footprint and maximum flexibility for the customer. We also offer Equipment Design services  and Product Design services as part of our comprehensive engineering solutions.

 

Note: Certain images and mechanical details have been modified to maintain client confidentiality.