Products Power Transmission Products

  • Shock Guard®

TGF Series Shock Guard®

1.Features

High attachment face precision
Pre-loading the support bearing of the drive plate eliminates gaps, and the attachment faces are ground for better output attachment face precision.
High precision
Backlash is extremely small, giving the unit good reset position precision -- ideal for indexers.
Easy torque adjustment
Users can easily adjust torque just by aligning the nut height.
Automatic reset
Once the cause of the overload has been removed, the unit will automatically reengage by just rotating the drive side.
One position type
The arrangement of the balls and pockets, which form the torque transmission elements, only engage in one position to create a unique combination.

2.Structure

TGF20 to 45

TGF20 to 45 Structure
  1. (1) Hub
  2. (2) End nut
  3. (3) Hexagon socket head set screw
  4. (4) Drive plate
  5. (5) Slide plate
  6. (6) Adjustable nut
  7. (7) Coil spring
  8. (8) Drive ball (Ball A)
  9. (9) Snap ring
  10. (10) Hexagon socket head set screw
  11. (11) Ball B
  12. (12) Ball C
  13. (13) Housing
  14. (14) Thrust bearing
  15. (15) Hexagon socket head set screw

TGF65 to 90

TGF65 to 90 Structure
  1. (1) Hub
  2. (2) End nut
  3. (3) Hexagon socket head set screw
  4. (4) Drive plate
  5. (5) Slide plate
  6. (6) Adjustable nut
  7. (7) Spring holder
  8. (8) Hexagonal countersunk screw
  9. (9) Coil spring
  10. (10) Drive ball (Ball A)
  11. (11) Bush
  12. (12) Snap ring
  13. (13) Hexagon socket head set screw
  14. (14) Radial bearing
  15. (15) Thrust bearing A
  16. (16) Thrust bearing A
  17. (17) Housing
  18. (18) Thrust bearing B

3.Principle of operation

Animation showing the operating principle of the TGF Series

During normal operation (engagement)
The TGF Series operates by transmitting torque from the hub to the drive plate on the output side through the drive ball. (Or the reverse.)
A sprocket and timing pulley are directly attached to this drive plate by bolts.
There is a hole in the hub's flange with several drive balls arranged inside. There is a pocket for drive balls in the drive plate on the output side. The drive balls transmit power under pressure from the coil spring on the thrust race.
TGE Animation GIF
During overload (trip)
The drive ball pushes up on the thrust race on the coil spring side when an overload occurs. It pops out of the drive plate pocket while rotating, which interrupts drive.
The cover on the coil spring side moves at this time. The TG sensor detects the amount of movement, and after the overload it can easily and automatically stop the drive power.
Recovery method
After overloading, it will automatically reset to its set position within one rotation after restarting.
The TGF Series will continue to rotate after activating and continuously reset, so after an overload and when the TG sensor detects the overload, be sure to immediately stop the drive power.

4.Model Numbering Example - TGF Series

TGF 20 - L 2 - T H 20 J D2 - N19
Series Size Spring strength Type Shock Guard side Shaft bore tolerance Shaft bore diameter (1mm units) Keyway tolerance Set screw positioning Set torque value

Size

  • 20
  • 30
  • 45
  • 65
  • 90

Spring strength

  • L: Weak
  • M: Medium
  • H: Strong

Type

  • 2: Type 2
  • 3: Type 3

Shaft bore tolerance

  • F: F7
  • G: G7
  • H: H7

Keyway tolerance

  • J: New JIS Js9
  • P: New JIS P9
  • F: Old JIS F7

Set screw positioning (Position from adjusting nut side)

  • D0 Set screw positioning fig.
  • D2 (Standard) Set screw positioning fig.
  • D3 Set screw positioning fig.
  • D4 Set screw positioning fig.
  • D5 Set screw positioning fig.

Set torque value

  • The torque setting is shown in N·m units.
  • *Shown to one decimal place when the torque setting is less than 10N·m.
  • Code T indicating Shock Guard side is used for no-coupling types as well.

5.Model Numbering Example - TGF Series Coupling Type

TGF 20 - L 5 - T H20PD2 - C H30PD2 - N18
Series Size Spring strength Type Shock Guard side Same notation as no-coupling type Coupling side Same notation as no-coupling type Set torque value

If the shaft bore is a pilot bore, the code for the Shock Guard side will be TR and the code for the coupling side will be CR.

Size

  • 20
  • 30
  • 45
  • 65
  • 90

Spring strength

  • L: Weak
  • M: Medium
  • H: Strong

Type

  • 5: Type 5
  • 7: Type 7

Shaft bore tolerance

  • F: F7
  • G: G7
  • H: H7

Keyway tolerance

  • J: New JIS Js9
  • P: New JIS P9
  • F: Old JIS F7

Set screw positioning *

  • D0 Set screw positioning fig.
  • D2 (Standard) Set screw positioning fig.
  • D3 Set screw positioning fig.
  • D4 Set screw positioning fig.
  • D5 Set screw positioning fig.

Set torque value

  • The torque setting is shown in N·m units.
  • *Shown to one decimal place when the torque setting is less than 10N·m.
  • Note: The set screw position of the Shock Guard side is as seen from the adjusting nut side, and the set screw position of the coupling side is as seen from the hub side.

Model numbers for Shock Guards changed on April 2, 2018.