Koppeling met palmechanisme in de terugtraprem.
By combining two ratchet mechanisms, the drive head down the catches by turning forward against the hub and back-pedaling against the brake shell. (See Figure 55)
The detent mechanism at A and B is used for the drive.
A position is at the driving situation.
Remove driver wants to turn clockwise harder than the hub.
The pawls are pushed outwardly against the hub.
In situation B turns the hub faster than the drive head (with freewheeling or back stairs). The catches are the boss came along a bit until they get in the lower part of the driver.
The detent mechanism at C and D is intended for pushing the brake shell to the outside. In situation C, the brake cone stationary or running forward.
The pawls are located between the cone and brake shell, and do not make contact with the brake sleeve.
In situation D the drive head and brake cone be turned back.
The pawls are thereby pressed against the brake shell which then presses against the hub.
The catches come loose again as the cone is rotated forward.
The brake cylinder must be securely connected to the frame via the brake lever.
If that were not the case it, then n would be by the rotation of the rotating hub to the front of the brake sleeve.
This would then brake cone, drive head and sprocket run forward through the detents.
In the Sachs Torpedo hub (see Figure 56) with coaster three situations can be distinguished:
- The driving position. The driving head presses the pawls on the driving portion to the outside. These come back to lie on the hub and push against the hub. The hub is driven. The brake cone rotates forward and retainers for the brakes are loose.
- The freewheel mode. The hub rotates faster than the driver. The pawls come to lie loose on the driving portion and the drive head is disconnected from the hub. The brake cone stand still relative to each other. The detents for inhibiting remain loose.
- The back-pedal mode. The driving cup and brake cone runs backward. thereby pushing the catches for braking against the brake sleeve. It expands and pushes the braking surfaces against the hub. The hub rotates faster than the driver. The retainers for the driving portion thereby remain loose.