IMPROVEMENTS ON MECHANICAL CONTRIVANCES FOR ELECTRO MAGNETIC CLOCKS AND APPARATUS."
Year: 1880

page_text: "
PROVISIONAL SPECIFICATION left by Johann Mayr at the Office of the
Commissioners of Patents on the 29th November 1880.
JOHANN MAYR, of Munich, in the Kingdom of Bavaria, Empire of Germany.
IMPROVEMENTS ON MECHANICAL CONTRIVANCES FOR ELECTRO MAGNETIC CLOCKS
AND APPARATUS."
My Invention consists in mechanical improvements, by means of which it is
possible to construct a new system of electric clocks and improved signalling
apparatus, and to replace the usual sliding spring and mercury contact by reliable
metallic contacts with impact motion and exactly controlable duration.
The first part of my Invention relates to contact breakers. Instead of mounting
the contact breaking tooth wheel on the axle of the quarter wheel, I mount it on
a separate axle, which may be driven by the hour axle of the electric standard
clock, and I use an anchor with movable pivot, the latter being fixed to the free
end of a short lever and pressed against the wheel by a spring.
The two points or teeth of the anchor are at such a distance from each other
that they can not simultaneously fall in between the teeth of the wheel, which
may have 60 teeth.
The extremity of the anchor lever oscillates opposite an adjustable contact screw
serving as a conductor to the electric current.
A modification of this contact breaker consists in replacing the uniformly toothed
wheel by two dises mounted on the same axis, each disc having one tooth, and the
relative position of the two teeth being made variable by securing one dise to the
other by means of screws or bolts passing through slots, which allow one disc to be
turned on the nave of the other. The two pallets of the anchor lever are in two
different planes, so that each pallet comes in contact with one of the discs only.
Only one contact takes place during a revolution of a disc, and the length of the
contact can be varied by altering the distance between the two teeth.
My Invention relates further to the means of converting the small reciprocating
motion of the anchor of electro magnets into the revolving motion of a wheel. I
replace the springs usually applied for turning a ratchet wheel by two ratchets or
hooks having the same length, and the axes of which are in the same line, said
ratchets being placed side by side and acting on the same tooth of the ratchet
wheel. The relative position of the two ratchets or hooks is made adjustable by
a set screw passing through a slot of one of the levers which carry the said
ratchets.

page_text: My Invention consists further in a device for enabling any secondary clock to
close a circuit for the following secondary clock, so that a great number of
secondary clocks can be supplied by a small battery.
During the return motion of the anchor of the electro magnet, when the
propelling ratchet is lifted over the next tooth, a small platinum spring touches a
contact screw, thereby closing a new circuit which passes through the following
(tertiary) clock. In order to render the travel of the anchor of the tertiary clock
independent of the duration of the current, that is to say, independent of the
variable resistances, the magnet anchor of the clock is provided with an arm of
soft iron, having its fulcrum on the magnet anchor and kept at a distance from a
contact screw by a weak spring. The said arm is much sooner attracted in
consequence of the closing of the circuit by the platinum spring than the main
anchor, which has to overcome a great resistance, and the attraction of the said arm
closes a new circuit for its own magnet, which will not be interrupted until the
main anchor has completed its travel. Another device for converting the motion
of the anchor of an electro magnet into the rotary motion of a wheel is as follows:-
The wheel to be set in revolution has near its circumference, a stop pin placed
opposite the nose of a radial arm, which is attached to a small spur wheel mounted
loose on the axle of the wheel to be turned. A tooth segment gears into the said
spur wheel, said segment being attached to the longer arm of a double armed
lever, the shorter arm of which is provided with a small platinum contact plate
placed opposite a similar contact plate attached to the longer arm of a magnet
anchor. By the said counterweight, the segmental lever, and thereby the small
spur wheel, with the arm attached to it, may be moved, so as to cause the stop
pin and consequently the main wheel to make a revolution.
The contact of the said small platinum plates close the magnet circuit, and the
ensuing attraction of the anchor imparts motion to the counterweight, thereby
setting in motion the gearing connected with the segment. The shaft of the driven
wheel may be provided with a pair of vanes or discs, which may serve as an air
brake or as signals.
My Invention consists further in a device for secondary clocks, which allows the
latter to be provided with much heavier hands, not liable to be moved accidentally
by a strong wind, &c.
The hands are turned forward by the weight of a driving lever, which lever is
lifted by the closing of the current from the standard clock, and placed on a pin
near the circumference of a ratchet wheel provided with 15 teeth and pins, and
mounted on the shaft of the change wheel.
The magnet anchor is pivoted at the top and forked at its longer arm, one side
of the fork serving to lift the driving lever, while the other supports one of the
pins of the ratchet wheel.
The turning power of the driving lever arranged in the manner just described,
may be applied in combination of the improved conversion gear described above,
and instead of moving the hands of clocks, the magnet anchor may be adapted to
move certain signals on railways or in other places.