Quality and Autogard are synonymous with overload protection. The company’s reputation for high quality products is derived from over 35 years of design innovation and production. Autogard products are manufactured to meet ISO 9001 using the latest machine tools and high quality materials.

The Series 400 has been designed to meet the emerging need for a high and low speed, free wheeling Torque Limiter. The Series 400 differs from previous ball detent designs by using two sets of balls on concentric pitch circles.

In the normal drive condition, torque is transmitted through the drive balls ‘A’. The inner strut balls ‘B’ are designed to carry no load during this time.

Disengagement on overload
When an overload condition occurs, the drive balls roll out of their seats forcing the slide plate ‘C’ and drive plate ‘D’ apart. The cage plate ‘E’, strut balls and drive balls all rotate until the cage plate hits a stop located in the slide plate. At this point the spring pressure has been transferred from the drive balls to the strut balls. The strut balls prevent the drive balls from re-engaging the drive plate. The coupling or driven media attached to adapter ‘G’ is now completely free to rotate. Although the Series 400 has been designed to run freely after disengagement, it is recommended that a shut-down switch is incorporated to avoid wear.

Re-engagement
Re-engagement occurs when either the driving side is reversed, or the driven side is advanced. Pawl ‘F’ engages the cage plate ‘E’ and rotates it until the drive balls are re-seated. Resetting must be done at low speed to permit the engaging mechanism to function properly in either direction and to prevent potential damage.

The resetting can be done manually or automatically by slowly inching the motor in reverse.

The Series 400 comes standard as a Rapid Reset (RR) style Torque Limiter. This gives the following maximum angles of rotation to re-engage: