• (1) Based on the strength, load, and other conditions of the mechanical device, determine the limit value beyond which torque should not be applied, and set this as the trip torque.
• (2) If the limit value is unclear, calculate the rated torque from the rotation speed and rated output of the shaft where Shock Guard is attached, and multiply this by the service factor in Table 1 according to the operating conditions to determine the trip torque.

If the operating speed is relatively high (approximately 500 r/min or above) or if the load inertia is large, the motor's starting torque may trip Shock Guard.

If there is a possibility of this happening, find the inertia ratio, calculate the torque acting on Shock Guard at startup, and multiply this by the service factor to determine the trip torque.

K = I_L + I_t I_s   K = GD²_L + GD²_t GD²_s   T_t = K・T_S + T_L 1 + K T_p = SF・T_t

• K: inertia ratio
• I _s: Moment of inertia on the drive side (kg·m ²)
• {GD ²_s: Drive side GD ² (kgf m ²)}
• I _L: Moment of inertia on the load side (kg·m ²)
• {GD ²_L: GD ² on the load side (kgf·m ²)}
• I _t: Shock Guard moment of inertia (kg·m ²)
• {GD ²_t: GD ² of Shock Guard (kgf·m ²)}
• T _s: Motor starting torque (N・m) {kgf・m}
• ​_Tt: Torque acting on Shock Guard at startup (N・m) {kgf・m}
• T _L: Load torque (N・m) {kgf・m}
• T _P: Trip torque (N・m) {kgf・m}
• SF: Service Factor

Note) For each moment of inertia, GD² and torque value, please use the converted value for Shock Guard mounting shaft.

If the torque acting at startup is larger than the load torque, the trip torque will also be larger, which may cause problems with overload protection.
(The trip torque is too large compared to the load torque)

In such cases, install Shock Guard as close to the load side as possible.

Select a model number where the calculated trip torque is within the range of the minimum to maximum torque of the transmission capacity.

Please check that the shaft to which you will install Shock Guard is within the range of shaft hole diameters available for Shock Guard model number you have decided on (see the dimension table).

If the shaft diameter is larger than the allowable range of shaft hole diameters, you can accommodate this by selecting a model number one size larger and using a weak spring.

Make sure that the rotation speed when using Shock Guard is within the maximum rotation speed.

• * When selecting the size based on torque, make sure the set torque is 80% or less of Shock Guard 's upper torque capacity limit. This is because Shock Guard will need to be readjusted to compensate for torque loss due to wear after years of use.
• * When driving with an induction motor, etc., take the starting torque into consideration when determining the set torque. Also, if large mechanical vibrations occur, Shock Guard will activate in response to momentary overloads, so it may appear to be operating at a lower torque than calculated, so please set the torque taking vibrations into consideration.
• * When used in an intermittent drive unit such as an indexer, if the difference between the set torque and the normal peak torque is small, load fluctuations during operation may cause the transmission ball to swing within the pocket, resulting in machine vibration and abnormal wear inside Shock Guard. Therefore, set the set torque as high as possible within the range that still protects the equipment.
• * Repeated operating torque accuracy is the value at the time of shipment from our company.
• * When using a V-pulley or Belt Sprockets mounted on Shock Guard, check whether the radial load generated by the belt tension satisfies the allowable value. If it exceeds the allowable value, please contact us.
• *Select the type by considering whether it satisfies each tolerance according to the coupling usage conditions.
• * When restoring rotation speed, please do so at the slowest possible speed. The recovery speed cannot be limited as it varies depending on factors such as the inertia of the driven machine, the elasticity of the drive side, and the selected torque of Shock Guard, but in general, recovery is possible at 50 r/min or less. If you are unable to restore at a low speed, please use the inching operation.

⚠Please avoid resetting the Shock Guard by turning the body or shaft by hand as this is dangerous.