Another WT.

These images were kindly sent to me by the new owner of a C40a WT movement. It is shown before any restoration has taken place. The small relay electromagnet on the left (which releases the gathering pallet at half minute intervals) is only missing because it had a broken tail. So it needed some "surgery" to ensure a good connection. Other than that the movement looks to be in very good condition indeed. The details of the movement suggest it was made some time in the 1940s.

This WT movement still shows the beautifully organic, early, curved shoulder to the mainframe over the drive electromagnets. Later examples have a straight, sloping section to the frame just here.

Here the Hipp Toggle damper can be clearly seen attached to the extreme right of the frame. A rubber hose on the end is supposed to touch the Hipp Toggle to damp its motion.

 A view of the rear of the movement showing the worm and wormwheel in the foreground. An extension shaft from the wormwheel leads to the first bevel wheel which drives the larger crown wheel on top. The slotted universal coupling can be clearly seen in the foreground. A T-shaped casting would rest in these slots to drive the motionwork of a dial in line with this coupling. The slots would allow for the thermal expansion of the lead off rods with wildly fluctuating temperatures normal for tower clock installations. Without some longitudinal freedom the lead off rods might buckle or bind as they expanded in summer temperatures. Note the glorious deep gold of the original, lacquered brasswork.

The right side of the WT movement with "ELECTRIC" cast into the metal of the frame. The compact dimensions of the very powerful WT movement are clearly seen here. A weight driven movement to drive the hands of four 6' dials would have been considerably larger in all dimensions. Not to mention the bulky weights and the vertical room they needed to lower themselves. To drive the clock movement for as little as a few days or only up to one week.

The Waiting Train end of the WT movement with its controlling relay electromagnet removed. The relay electromagnet's support plate is still present. The heavy pendulum bob on its stub shaft has been temporarily removed while the WT movement is restored. "PULSYNETIC" is cast into the main frame on this end. This was a trade name for Gents' public timekeeping products.

A more general view of the rear of the WT movement. Two bevel wheels appear to be missing at the front and back of the crown wheel support block. Including the forward facing one which usually carries Gents', the makers name, "Pulsynetic" and a time setting dial. The original time pointer remains as do the work-polished stub axles for the missing bevel wheels. Not all WTs were made to drive the hands of four dials. In this case it seems all the parts are present for four dials except for the two bevel wheels themselves. Though WT spares are incredibly hard to find new replacement bevel wheels are not impossible to obtain. Even a good copy of the time setting dial can be engraved to order using an existing example.

The large, drive electromagnets with the hinged, rocking armature on their right. A roller on the top of the armature engages with the extended hook of the pendulum rod just above. This engagement only occurs when the large, drive electromagnets are energised at intervals by the Hipp Toggle and V-block. These parts act as a simple and reliable minimum arc sensing switch for the pendulum. The ingeniously simple Hipp Toggle and V-block were invented by Matthias Hipp, a German clockmaking genius somewhere around 1843.  

The rear of the pendulum, ball bearing, support case is clearly seen here along with the bifurcated top to the pendulum rod. Using two, long life, ball bearing races instead of a potentially fragile, rusting suspension spring was only possible thanks to the unique design of the WT. Since the WT pendulum has no duty of precision timekeeping any variation in friction of the pendulum support bearings has no importance at all. Normally, weight driven clocks rely heavily on friction remaining completely unvarying to ensure good timekeeping. The ingenious WT passes its precision timekeeping duties over to the master clock which controls it. Variations in arc and frequency of impulsing are completely irrelevant in the WT design as far as timekeeping is concerned. Thanks to its worm gearing and powerful pendulum drive electromagnets the WT is really a very low speed, high torque, electric motor. The master clock provides the half minute impulse which restarts the Waiting Train mechanism and thus the drive to the clock hands. Maintaining an accuracy for the exposed clock hands of as a little as a second per week. Or even less.

Click on any image for an enlargement. Back click to return to the text.

No comments: