Inclined conveyors and bucket elevators in the cement and mining sectors face major risks from uncontrolled reverse motion caused by large mass inertia. Backstops in these systems must withstand high torque and rapid engagement at speeds of up to 3,600 rpm. Traditional clutches often fail because friction wear during continuous overrunning creates a gap between operational needs and component capabilities.
To address this challenge, advanced non-contact solutions such as the Tsubaki BR-HT series cam clutch have been developed for high-speed, high-torque backstopping.
Traditional cam clutches often struggle in applications where high overrunning speeds and torque coexist. Continuous contact between internal components causes wear, heat generation and reduced operational life. The BR-HT Series overcomes this limitation through its lift-off non-contact design, ensuring engagement occurs only when required and eliminating unnecessary friction during free rotation.
The result is a solution engineered for high-speed overrunning applications, particularly suited to inclined conveyors and bucket elevators where reverse rotation must be prevented reliably.
Key features and technical specifications
Lift-off non-contact design
The BR-HT series is built around Tsubaki’s lift-off non-contact cam design, which changes how a cam clutch behaves during operation. In conventional designs, internal components remain in contact even during overrunning, leading to continuous friction, heat generation and wear.
By contrast, the BR-HT disengages its cams completely when the inner race overruns, creating a true non-contact condition. This removes unnecessary friction, significantly reduces thermal build-up and ensures wear occurs only during brief engagement phases. As a result, service life is no longer dictated by continuous friction but by fatigue during actual load transmission, substantially increasing operational longevity.
High torque capacity with compact integration
BR-HT is designed for torque capacities ranging from 105 Nm to more than 366,000 Nm, bore sizes from 20 mm to 320 mm, and operating speeds up to 3,600 rpm. It combines high performance with design flexibility. Its ability to be mounted on high-speed shafts allows engineers to choose more compact and cost-efficient system layouts without compromising safety or reliability.
Rollover cam
It incorporates a non-rollover cam design with a flat cam profile that enhances stability under high torque conditions. This flat surface prevents cam rollover and ensures secure wedging between races, even under shock loads or motor stall scenarios. As a result, the clutch delivers reliable, slip-free backstopping and protects the system from reverse rotation.
How it works: Technical mechanism
The BR-HT cam clutch operates using a cam-and-race mechanism housed within a cage between the inner and outer races.
Normal operation (overrunning): When the inner race rotates faster than the outer race, the cams disengage completely, creating a non-contact condition.
Backstop function: If reverse rotation occurs, the cams instantly wedge between the inner and outer races, locking them together and preventing backward motion. This instantaneous mechanical locking ensures reliable backstopping even under high torque loads.
A new standard in cam clutch performance
The Tsubaki BR-HT cam clutch addresses the core limitations of conventional backstopping solutions. By combining non-contact operation, high torque capacity and compact integration, it delivers reliability where failure is simply not acceptable.
For engineers and plant heads evaluating backstopping solutions, the question is no longer whether to use a cam clutch, but whether it can withstand high-speed conditions without compromising lifespan. Evaluate your current systems. If the risk of reverse rotation exists, contact the team to explore whether the Tsubaki BR-HT cam clutch can improve operational safety and reliability.