Clamps TB-50 and TB-41 POMA gondola lift

The T/TA clamp

The T/TA clamp is the clamp that followed the S clamp.

The clamping force of this new clamp is transmitted directly from the springs to the jaws that clamp the cable. There are no more intermediate parts.

The TA clamp differs from the T-clamp in particular by the shape of the fixed jaw.

The springs are for the T/TA clamps arranged vertically along the seat line. The lever is pointing upwards.

between the T-clamp and the TA, the winding direction of the springs has been reversed.

We notice that the two needles are not of the same size. (In the photo above, it is slightly damaged).

The needle is longer on the front side of the clamp in the direction of travel than on the rear side. The needles are either made of plastic or steel.

In the case of a steel needle, a maximum upward deflection of 5° is possible only (for the passage under compression with a reversal of the curvature of the fast cable).

The clamp has two springs inside each other to increase the clamping power of the jaw on the cable.

When disengaging, the disengagement cam will press on the lever roller to release the cable from the clamp.

The needles are absent, moreover, on this demonstration pliers, the springs have been lightened (and there are only one against two left in practice)

For the T and TA clamps, the springs measure approximately 400mm (the inner spring being longer than the outer spring).

The lever travel is about 150mm.

This system requires the clamp to be closed again in the station, once the cable has been disengaged.

With the T/TA clamp came the tyre launchers, because previously, with few exceptions, the launchers of the S-clamp gondola lifts accelerated the vehicles thanks to gravity.

The TB pliers

The TB clamp is a clamp used since about 1985 on detachable chairlifts :D

It equips the majority of detachable chairlifts of the Alpha Evolutifs type, and all detachable chairlifts before the OmegaT and Satellit stations.

It also equips 4-passenger gondolas where the number of clamps used per clamp has been reduced from 2 for S clamps to 1 for TB clamps.

TB clamps are generally very very similar to T/TA clamps.

There are 3 models of TB clamps:

TB40, TB41 and TB50.

The TB pliers are distinguished by :

a frame, rollers, a fixed jaw linked to the frame, a mobile jaw, a roller on which the clutch cam acts (or disengagement cam)

two springs inside each other, such as T/TA clamps, two needles of the same length and finally a tread plate for the tyres.

The basic principle of the clamp is the same as the T/TA:

Here is a picture of the end of the lever with the roller on which the engage/disengage cam is going to rest

The winding of the springs is also noticeable. (Photo by Guillaume)

The main differences between the TB40, 41 and 50 are differences in the dimensions of the collet (jaw machining diameter, minimum and maximum clamping diameter, reference dimensions of the springs, etc.).

Note that for info, the TSD6 of the Tour in Avoriaz, the first TSD6 :D is equipped with TB41 clamps.

Here is an overall picture of a TB50 clamp placed on the ground for maintenance, with the various components.

the lever travel of the clamp is also about 150mm.

As for the connection to the seat suspension, the pivot connection that this creates is damped by friction washers (from 1987).

From 1989-1990 the mobile jaw of the TB clamp has a so-called "moustache" shape (see photos).

A TB clamp on the cable (TSD4 of the Grand Jeu à Aussois)

The TB double gripper

The double clamp TB is only used on gondola lifts, from 6 to 12 seats.

The double TB clamps consist of two conventional single TB clamps connected by a crossbar which also serves as a fixing with the vehicle's suspension system. The two fixed jaws are connected by a flexible link.

The double TB are also available in several models:

TB40, TB41, TB50 and TBS50.

There's not much else to say about this double TB.

just that the double TBS 50 has a total of 8 springs: 4 per clamp: the springs are for this model of clamp arranged one inside the other then one above the other: see sketch below:

Here is a picture of the TBS50 clamp (Orelle gondola)

and a photo of TB41 (TC12 from the Ice Rink in La Clusaz)

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