ROBA-DS 9120 Aluminum Coupling Cuts Inertia for EV Test Stands
E-mobility test stands demand wider speed ranges, tighter measurement accuracy, and faster dynamic response than traditional drivetrain test environments—while still requiring the precision and process safety that torque measurement depends on.
The ROBA-DS 9120 is a weight-optimized aluminum shaft misalignment compensation coupling built on the ROBA-DS steel disk pack coupling platform. Compared to the steel version, the outside diameter is reduced by up to 0.39 in (10 mm), and mass and mass moment of inertia are 40% to 60% of the steel version depending on design and size—with no reduction in performance density. The coupling supports speeds up to 32,000 rpm.
The balance between rigidity and elasticity is designed to minimize restoring forces on connected system components. A balance quality of G 2.5 at 5,000 rpm supports smooth, low-vibration operation across the full speed range—a direct factor in measurement accuracy. Standard manufacturing tolerance is IT6. A nickel-plated surface, stainless steel disk packs, and galvanized connecting screws provide corrosion protection. Backlash-free shaft connections are achieved via shrink disk hubs or external shrink disk hubs, supporting reproducible measurement results. The coupling is compatible with common torque transducers and is configurable through a modular construction system with multiple connection variants, scaling from R&D test stands to end-of-line testing.
For test stands with vertical axes or linear motion—common in automotive drive testing—the ROBA guidestop profiled rail brake acts directly on moving masses, clamping them in a backlash-free, high-rigidity hold. It is available in hydraulic, pneumatic, and electromagnetic configurations and is compatible with common linear guides. The ROBA linearstop piston rod brake secures linear movements on round rods, operating on a fail-safe (de-energized closed) principle for dynamic emergency braking; the series covers six sizes with holding forces from 15.7 to 3,822 lbf (70 to 17,000 N). The ROBA-stop M series provides a compact motor brake for installation directly at the drive motor, functioning as either a holding brake or a dynamic stopping brake.
The ROBA brake-checker module monitors safety brakes without sensors while simultaneously supplying them with power. Using current and voltage analysis, it detects switching conditions and issues a warning before a brake can no longer release under current operating conditions. It flags boundary conditions including supply voltage that is too low, undersized supply lines, elevated coil temperature, and enlarged air gap. Combined with the ROBA gateway module, brake data is continuously readable via Ethernet and displayable on a dashboard, enabling early anomaly detection, planned maintenance scheduling, and integration into remote maintenance systems.
Applications
- Shaft misalignment compensation in test stands
- High-speed torque measurement up to 32,000 rpm
- Vertical axis and linear motion securing
- Dynamic emergency braking on round rod actuators
- Sensorless brake condition monitoring
- Remote maintenance integration via Ethernet
Industries
- Automotive
- Electric vehicle / e-mobility
- Research & development
- End-of-line manufacturing testing
Who It's For
- Test stand engineers requiring high measurement accuracy across speed ranges
- Applications where low mass inertia directly affects dynamic test response
- Vertical axis test configurations needing fail-safe load holding
- Facilities requiring planned brake maintenance over unplanned downtime
- Test environments integrating remote monitoring or diagnostics
Features
- Aluminum variant of the ROBA-DS steel disk pack coupling
- Outside diameter reduced up to 0.39 in (10 mm) vs. steel version
- Mass and mass moment of inertia: 40–60% of steel version (design/size dependent)
- Max speed: 32,000 rpm
- Balance quality: G 2.5 at 5,000 rpm
- Manufacturing tolerance: IT6
- Nickel-plated surface; stainless steel disk packs; galvanized connecting screws
- Backlash-free connection via shrink disk hubs or external shrink disk hubs
- Compatible with common torque transducers
- Modular construction with multiple connection variants
- ROBA guidestop profiled rail brake: hydraulic, pneumatic, and electromagnetic versions; compatible with common linear guides
- ROBA linearstop piston rod brake: 6 sizes; 15.7 to 3,822 lbf (70 to 17,000 N) force range; fail-safe (de-energized closed)
- ROBA-stop M: compact motor brake; holding and dynamic braking modes
- ROBA brake-checker: sensorless monitoring; simultaneous power supply; detects switching condition, voltage issues, coil temperature, air gap changes
- ROBA gateway module: Ethernet connectivity; dashboard visualization; remote maintenance integration
Mayr Corporation
Mahwah, NJ
(201) 445-7210
[email protected]
mayr.com