BMG’s range of Tsubaki cam clutches comprises the BR-HT (Backstop Reducer High Torque) series, designed for use in equipment that includes inclined conveyors and bucket elevators. These backstop cam clutches offer optimised speed over-running and higher torque than conventional cam clutches, to prevent reverse rotation of drive shafts, thus avoiding damage to machinery and expensive equipment and also enhancing safety.
The BR-HT series – which is available from BMG in a selection of 65 units, with bore sizes from 20 to 320 mm, – provides torque capacities from 105 Nm to 366 000 Nm and maximum over-running speeds from 1 000 rpm to 3 600 rpm.
“These robust backstop cam clutches, ideal for OEM applications, have a special integrated design of centrifugal lift-off cams that provide mechanical engagement only when needed and optimised speed-overrunning, with no contact between cams and races,” says Carlo Beukes, BMG’s Business Unit Manager, Power Transmission division. “At all other times, the cam clutch rotates freely, with no mechanical contact in the clutch mechanism. The advantage of this non-contact operation is extended service life.
“The design of the BR-HT clutch series features a full complement of cams to provide the maximum number of load-transmitting members per given diameter. This results in greater torque capacity, size-for size, compared with other types of one-way clutches.”
The simple design, in which the cam clutch mechanism is incorporated in a cage between standard-dimension inner and outer bearing races, allows the cam clutch to be easily integrated into a wide range of mechanical systems. The facility for this type of mounting is further enhanced by a keyway that simplifies installation, by ensuring positive location and fixing of the clutches onto shafts.
With the outer race of the clutch anchored to a stationary member, the inner race can overrun freely in one direction of rotation, even at high speed. Reverse rotation is instantaneously prevented by the automatic engagement of the clutch.
South Africa’s Mine Health and Safety Act states that the installation of incline conveyor belts must include the fitting and use of one or more devices to prevent run-back or run-on to prevent injury by materials or minerals falling from a conveyor belt. Tsubaki back stop cam clutches – designed for safety in high or low speed applications meet the requirements of this legislation.
BMG’s technical team advises on the selection of the correct cam clutch for each application and the appropriate installation and usage for optimum performance and improved safety standards. For extended service life, correct lubrication methods and dust prevention care are also critical.
