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I have been kindly sent some excellent images by the custodian of an original Pulsynetic installation at Niagara-on-the-Lake: A town not far from the world famous Niagara Falls.Here is a link to Google Street View showing the location of the Niagara-on-the-Lake, Old Courthouse and Cenotaph. I recommend a tour to enjoy the very attractive historical architecture and many small shops in the area:
https://maps.google.clock tower memorial at niagara on the lake
The system once had a Pulsynetic C7 master clock but this has become separated from the site. A synchronous motor, rather than electromagnets and pendulum, has taken over drive duties for the WT behind the dials in the impressive Cenotaph. The rest of the system in housed in the old town courthouse and also includes a C54 Pulsynetic bell striker. The bell is housed in a tower on the roof. (As seen above)
Here is a general view of the striking system. The long arm pulls the bell hammer wire when actuated by the large brass, snail-shaped cam. The electric motor on the left provides the motive power.
A closer view of the bell striker. It lacks a brake to the motor shaft but continues to give good service. There have been some modifications to the unit over time. An electronic timer is now used to silence the strike when desired.
A fine example of a C68 contact maker. This unit has a heavy duty, impulse slave drive to keep the time and close a contact each hour via a pin on the impulse wheel to release the striking mechanism.
Allan, the custodian of the system, would be very grateful for some indication of the likely dates for the components shown here. They are believed to be quite early judging from their style. Alan hopes to eventually recover the master clock to complete the original system. Then arrange descriptive material to guide visitors at the historic, Niagara-on-the-Lake, Old Courthouse.
This middle period Gents' C40A WT is being driven by a synchronous motor via the ratchet wheel/worm shaft.
The period of the movement can be recognised by the sloping member to the right side main casting, grey paintwork, attached company name plate, pressed steel contact steady bars and bandaged electromagnets.
It would be fascinating to discover why a later WT forms part of a ca.1920s Pulsynetic, striking clock installation. I have no data to support the dating of WTs but would guess from subtle details that this one is from the 1940s(?). If anyone can provide a more accurate date then please do get in touch.
The synchronous motor has been attached without removal of original WT parts. The danger is always that a clumsy conversion will result in the loss of vital and completely irreplaceable parts. As often happened with weight driven turret clocks at the hands of some companies in their haste to provide motive power which avoided regular, manual winding.
I have visited 18th Century turret clock installations where the barrels and pendulum bob are simply lying in the ankle-deep, fallen plaster debris on the clock room floor!
One of the cast iron and opal glass skeleton dials is visible in the background. Due to breakage, the opal glass has been replaced by translucent plastic. Modern low energy bulbs provide even illumination behind the dials at night.
Here is a side view showing a universal coupling and lead off shaft in the foreground. These drive the hands of a single dial via lead-off rods and motionwork. (12:1 gears between the minute and hour hands) ) The bevel gear cluster behind the WT movement has been housed in a protective metal gearbox.
The motor is seen side-on (in profile on the left) and uses a form of coupling to the WT's worm shaft.
There is always a danger with a worm and wormwheel that the very large amplification of torque can cause serious damage if anything should seize up further along the drive train. An ice storm might freeze the clock hands solid, for example.
A deliberately weak drive coupling will give way long before too much torque is applied through the wormwheel reduction gears. The slow speed of the motor drive bodes well for the longevity of this system. It is fortunate that the WT remains complete. Many important, weight driven, clock movements have lost vital components once they have been "electrified." Fortunately the application of the electric motor drive was carried out with great care and consideration for the originality of the WT installation. Even down to using original fixing screws to support the motor support plate.
Here are the contact assemblies from the N-o-t-L WT C40A.
Note the yellowed appearance much like of brass of the heavily oiled components above. Once cleaned the true materials are now obvious. Such over-oiling is not only unsightly but can quite easily insulate the active surfaces of the electrical contacts!
WTs rely completely on the main contacts, on the right, for their drive power to the electromagnets. Any increase in resistance, usually due to oiling, will reduce the power available. Probably increasing the frequency of impulsing. Which will reduce the power reserves available. This enormous power reserve, from automatically increased impulsing, was what popularised the design in the first place.
Where a WT is proving unreliable it might be wise to carefully examine the contacts for oiling. Cleaning may be all that is required to return the WT to normal service.
The Hipp Toggle operates just above the contacts. If the Toggle and V-Block are over-oiled then contact problems are almost inevitable. There is probably no need for abrasion. Drawing a paint thinners-damped, clean rag through the contact points, while pressing them gently together, may completely solve the problem.
Warning! Remember to isolate the power before trying this! The pendulum and its huge drive electromagnets may be suddenly kicked into life and trap incautious fingers! Remove solvent soaked rags from the clock room to avoid spontaneous combustion!
Provisional dating of the contact maker and bell striker is the 1920s. This is according to the acknowledged expert: Colin Reynolds. Ex-director and archivist of Gents and author of a number of fascinating books on Gents' timekeeping products. Sight of the original C7 master clock's serial number will help to confirm the exact date. Since the clock numbering and exact date can usually be confirmed by the adhesive label applied inside the Pulsynetic clock cases.
The street scene outside the Niagara-on-the-Lake, Old Courthouse with the imposing Cenotaph resplendent in bright sunshine with its carefully tended flowers around the base.
I must reiterate my gratitude to Allan for sharing these excellent images of the system he cares for.
Click on any image for an enlargement.
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