Telechron, Inc., Ashland, Massachusetts, USA. Model Type E, c. early
1930's, serial no. 17.
The restored movement is shown before being installed and wired in. Notice in the
second photo the circular aperture in the dial face just below the 12 o'clock position.
This was present in many of Henry Warren's domestic electric clocks as a warning indicator
in the event that the clock had lost power. If there was an interruption a magnetically
held flag would be released behind the dial aperture giving the opening a red color;
warning the observer that the time was in error. Clearly Warren had simply taken a dial
from his domestic clock stock to incorporate in this movement. The entire flagging
mechanism is eliminated and a simple piece of metal is glued behind the aperture. Even the
dial's numerical design and hands are out of step with the rest of this clock's design.
It's curious that Mr. Warren would not make a dial for this application considering that
this was not a cheap clock. Why scrimp on the dial - a component that the customer would
first notice? This same anomaly is seen on the file photo
of the prototype clock taken in January 1930 as depicted in the NAWCC Bulletin,
August 1991, page 392 as well as the only other known example. Perhaps it was thought that
in a greater production run a custom dial would be incorporated, but considering the fact
that not many were made, it never happened.
All of the movements components are finished in a brushed silver surface. Another nod
to the art deco look that was incorporated into the case. The underlying material is of
several metals. The main movement plate and front triangular subsidiary plate are steel.
The secondary rear plate upon which the motors are mounted is aluminum. All of the train
wheels are brass with the exception of the large epicyclical wheel and its components
which are aluminum.
The first photo below is of the differential gear system that coupled with the
commutator shown in the second to the last photo translated Warren's patented frequency regulation system into an output that
could control a specialized motor or other actuator to accurately control the frequency of
a power system. The next and last photos show some of the complex cam and lever works that
comprise the automatic frequency regulation.
The circular porthole glass which has a crack, is yet to be replaced. It acts as a dust
cover protecting the knife edge suspension upon which the pendulum impulse and frequency sampler is mounted. The rest of the critical
moving components move in hard plastic pivots. These require no oil and are suitable for
this application since there is negligible torque on the wheel and cam components; unlike
a conventional clock where there are very high forces in the lower end of the train which
would tear up such pivots in a short time.
The armature pictured below is a commutator that can rotate in either direction or be
paused, depending on the corrective current impulses from the frequency sampler as
dictated by the pendulum. It transforms them into proportional rotative motions in the
commutator which distributes these movements electrically to various indicators or
controlling devices, mainly Warren's patented rotation
reproducing motors which were used to control the generators in power stations. View
the videos to observe this in action.
The first video shows the front view. The three incandescent lamps are not an original
feature but was put in to demonstrate the output of the commutator. The combination of
electrical output would be used to control a device to regulate the generators in a power
plant or other device. Very similar to the function of a governor. In the second video one
can see the epicyclical wheel rotation and in the third it's rotation in step with that of
the commutator. The epicyclical wheel is tied into the regulation of the clock's dial
while the commutator sends the same motions as electrical commands for remote control. The
fourth and fifth videos show the frequency sampler driven by a rotating cam and delivered
via a set of stepped contacts to the bi-directional motor connected to both the
epicyclical wheel and commutator. Last two show an overall view of the clock before and
after restoration. It should be noted that under normal operating conditions the
bi-directional motor and thus the epicyclical wheel as well as the commutator would move
quite seldom. After all adjustments are made and the system has time to settle, the line
frequency and the pendulum would generally be in agreement. I have purposefully upset this
equilibrium for purposes of this display.