Improved Electric Switch.
Year: 1892

page_text: Date of Application, 1st Oct., 1892
Complete Specification Left, 27th June, 1893-Accepted, 12th Aug., 1893
PROVISIONAL SPECIFICATION.
Improved Electric Switch.
I DAVID LOCH 55 Calvert Road East Greenwich in the County of Kent
Philosophical Instrument Maker do hereby declare the nature of this invention to
be as follows:-
The switch is mounted on a slab, or back of wood, or other nonconducting
material, (preferably provided with a cover) which may be placed in any convenient
position, and the switch bar is caused to move between two stop pins, or studs both
to open, and close the circuit by the pull of a cord.
Figs. 1 and 2 of the accompanying drawings are front views of the switch
without the cover, and showing the sliding bar pulled down, the former showing
the circuit closed, and the latter showing it broken.
Fig. 3 is a side view of the switch with the cover in section, and showing the
sliding bar pulled down.
A is the switch bar of brass or other conducting material pivotted at a, to a plate
of sufficient thickness to allow the end of the sliding bar C, to move freely
underneath.
At the lower end, or end of the switch bar A, which overlies the sliding bar C,
is an aperture of say a heart shape in which slides one end of the stud, or pin c¹ of
the bar C.
B B are terminal clips of ordinary construction fixed on the back I, and to these
clips are attached the electrical conducting wires in the manner shown.
C, is the sliding bar of brass, or other material at the upper end, or end which
underlies the heart shaped aperture of the bar A, is say a V shaped slot which
slides over the stud or pin D.
Near the lower end of the said bar C, is an oblong slot which slides over the stud
or pin E.
H, is an oblong plate of brass, or other material sunk in the base I, & having
say an inverted V shaped slot in which slides the point of the pin c¹.
When the cord c, which is like an ordinary bell pull is pulled it causes the bar C,
to slide, and at the same the helical spring G, being on one side of the dead centre
at a, draws to one side the end of the bar C, which underlies the heart shaped
aperture of the bar A, therefore one of the angular surfaces of the V shaped slot
pressing against the pin, or stud D, causes that end of the bar to move at an angle,
and the upper end, or head of the pin cl, sliding on one side of the heart shaped
aperture of the bar A, causes the said bar A, to turn on its centre at therefore
the other end of the bar A, moves at the same time in an opposite direction until
it arrives at one of the stops F.
a,
The lower end or point of the pin c', sliding at the same time in the slot of the
plate H, thus prevents any torsion of the bar C.
The helical spring G, attached to the studs, or pins a', of the bar A, and c', of
the bar C, now being on the other side of the dead centre at a, of the bar A, holds
the bar A, in its place against one of the stops F.
The downward motion of the bar C, is checked by the pin E, and is also partly
held in its place by the said pin E.
When the pull on the cord c, is released the helical spring G, brings the bar C,
back to its former position, and a repeated pull of the cord must therefore cause
the action of the switch to be reversed.
Dated this 1st day of October 1892.

page_text: COMPLETE SPECIFICATION.
Improved Electric Switch.
.I, DAVID Loch, of 55 Calvert Road, East Greenwich, in the County of Kent,
Philosophical Instrument Maker do hereby declare the nature of this invention, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
This switch is mounted on a slab, or back of wood, or other non-conducting
material, (preferably provided with a cover) which may be placed in any convenient
position, and the switch bar is caused to move between two stop pins, or studs both
to open and close the circuit by the pull of a cord.
Figs. 1, and 2, of the drawings filed with the Provisional Specification are front
views of the switch without the cover, and showing the sliding bar pulled down,
the former showing the circuit closed, and the latter showing it broken.
Fig. 3, is a side view of the switch with the cover in section, and showing the
sliding bar pulled down.
A, is the switch bar of brass or other conducting material pivoted at a, to a plate
of sufficient thickness to allow the end of the sliding bar C, to move freely under-
neath. At the lower end, or end of the switch bar A, which overlies the sliding
bar C, is an aperture of a heart shape in which slides one end of the stud or pin c
of the bar C.
B, B, are terininal clips of ordinary construction fixed on the back I, and to
these clips are attached the electrical conducting wires in the manner shown.
C, is the sliding bar of brass, or other material, at the upper end, or end which
underlies the heart shaped apperture of the bar A, is a V shaped slot which slides
over the stud or pin D. Near the lower end of the said bar C, is an oblong slot,
which slides over the stud or pin E. H, is an oblong plate of brass or other
material sunk in the base I, and having an inserted V shaped slot in which slides
the point of the pin c¹.
When the cord c, which is like an ordinary bell pull is pulled it causes the bar C,
to slide, and at the same time the helical spring G, being on one side of the dead
centre at a, draws to one side the end of the bar C, which underlies the heart
shaped aperture of the bar A, therefore one of the angular surfaces of the V shaped
slot, pressing against the pin or stud D causes that end of the bar to move at an
angle, and the upper end, or head of the pin c', sliding on one side of the heart
shaped aperture of the bar A. causes the said bar A, to turn on its centre at a,
therefore the other end of the bar A, moves at the same time in an opposite
. direction until it arrives at one of the stops F.
The lower end or point of the pin c', sliding at the same time in the slot of the
plate H, thus prevents any torsion of the bar C. The helical spring G, attached
to the studs or pins a¹, of the bar A and c³ of the bar C, now being on the other
side of the dead centre at a, of the bar A holds the bar A, in its place against one
of the stops. F.
The downward motion of the bar C, is checked by the pin E, and is also partly
held in its place by the said pin E.
When the pull on the cord c attached to the pin is released the helical
spring G, brings the bar C, back to its former position, and a repeated pull of the
cord must therefore cause the action of the switch to be reversed.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
.
1. In an electric switch, the combination of the various parts constructed in the
manner herein described and illustrated for the purpose specified.

page_text: 2. In an electric switch, the switch bar A working on a pivot and the heart
shaped aperture, substantially as herein described and according to the drawing.
3. In an electric switch, the combination of the pin c¹ fixed to plate H working
in the heart shaped aperture and the sliding bar C with the V shaped slot and the
stud or pin D, substantially as herein described and according to the drawing.
4. In an electric switch, the sliding bar C with a slot and pin and the helical
spring G operated by a pull down cord, substantially as described.
5. In an electric switch, the switch bar and the terminal clips B with stops F
mounted on a plate I, substantially as described.
Dated this 27th day of June 1893.
J. P. BAYLY,
18, Fulham Place, W., Agent for the Applicant.