Improvements in Electrical Switches.
Year: 1898

page_text: Date of Application, 4th Nov, 1898
Complete Specification Left, 18th Feb., 1899-Accepted, 1st Apr., 1899
Improvements in Electrical Switches.
I, WILSON HENRY STURGE, of 17, Frederick Road, Edgbaston, in the City of
Birmingham, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:-
This invention relates to improvements in electrical switches and is primarily
intended for lamp holder key switches, but which or parts of which may be
applied to other switches.
It consists somewhat as follows:-As applied to a lamp holder key switch:--
The lower part of the fitting forms the usual bayonet joint (or screw) socket for
the attachment of lamp. Upon this is carried a porcelain or the like nonconduc-
tive block or frame to which are attached the wire connections, and the contact
plates. This is surrounded by two metallic semi-cylindrical covers, and a metallic
cap, through which latter the wires pass to the connections upon the porcelain
frame. The one semi-cylinder is secured in position by suitable screws to the
upper can and lamp socket, and is further provided with a side opening to receive
the switch action. This switch action consists of a square (or the like) spindle,
at whose outer end is the kev by which it may be part rotated. Adjoining the
key is a screw collar, which takes into a screwthread in the before named opening
in the side of the one semi-cylindrical cover, and by which it is secured thereto.
Next this collar and passing through an enlargement upon the spindle is a
pin whose ends project from each side, so that they, may (in part rotation) move
upon the surface of a sliding cam, of what is known as the "hill and dale"
type. This cam is preferably stamned from sheet metal, and has two opposite
gradual rising and two opposite sudden dron, and two short flat surfaces. Unon
these two flat surfaces are formed stop projections. The said cam is free to rotate
upon the spindle, but such movement is governed by a projecting peg upon the
periphery of the cam engaging with a slot opening in the screw collar. Forward
of the cam and part rotative with the spindle, is an insulated collar or disc upon
whose front face is secured a metallic ring. such disc resting against a coil
spring between it and the end of the spindle. Between the cam and the disc there
may if desired be a cushion like spring plate. Hence when in its working position:
by turning the key, the projecting pins upon the spindle ride up the gradual
inclines of the cam until they reach the stops, and in so doing push it forward
and with it the insulated disc having the metallic surface. By reversing the
key rotation, the whole of the parts .carried upon the spindle are carried around
for a short distance permitted by the travel of the peripherical peg upon the cam
in the slot orenings in the screw collar. Upon a further slight portion of rotation
the pins reach the incline, when the force of the coil spring suddenly drives the
cam back rast the pins, and of course the contact disc with it, thus producing a
sudden "break."
Reverting again to the porcelain interior:-This consists of a circular base
having two vertical walls, the one diametrically across the centre and the other
midway from such wall to the periphery, thus leaving the one half side flat.
This flat side is placed opposite the switch action, and upon its surface are secured

page_text: the contact metallic segmental surfaces, one of which latter passes through the wall
to the wire connection upon the other side. while the other is carried downward
to the plunger connection to the lamp. The other wire connection is made to
the shorter wall and thence downward to the other plunger connection to lamp.
Hence the wire connections are kept quite distinct and hidden from the switch
mechanism.
The other semi-cylindrical cover is now attached by a screw or screws, com-
pleting the general cylindrical form. Thus by the removal of this cover the wire
connections can be readily made without interference with the switch action
while the latter can also readily be removed if desired, by unscrewing the collar
from the other semi-cylindrical cover.
Dated this 3rd day of November 1898.
CHARLES T. POWELL,
Applicant's Agent.
improvements in Electrical Switches.
I, WILSON HENRY STURGE, of 17. Frederick Road. Edgbaston. in the City of
Birmingham. Electrical Engineer, 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 invention relates to improvements in electrical switches. and is primarily
intended for lamp holder key switches, but which or part of which may be applied
to other switches.
In order to more clearly explain this mv invention I have appended hereunto
drawings. having ficures and numbers of reference, and in which similar reference
numbers indicate the same part throughout the several views.
Fig. 1. is an external view of a key switch to which this my invention is applied.
Fig. 2. is a sectional plan view of the switch on line A-B Fig. 1.
Fig. 3 is a sectional view in elevation of the casing with the interior removed.
Fig. 4. is also a sectional view in elevation of the casing with the interior
removed, but taken at right angles to that shown in Fig. 3.
Fig. 5. is a front view. and Fig. 6, a side view of the porcelain block.
Figs. 7. 8 and 9, are front, plan, and side views of the switch action cam.
Fi. 10, is a front view of cushion spring blate.
It consists as follows: The lower part of the fitting forms the usual bavonet
joint (or screw) socket 12, for the attachment of lamn. Upon this is carried the
porcelain or the like nonconductive block 13, to which are attached the wire con-
nections 14 and 15, and the contact plates 16. 16*. This block 13 is surrounded
by two metallic semi-cylindrical covers 17 and 18. and a metallic cap 19. with
or without the cord grip 20, through which latter the wires rass to. the connections
upon the porcelain block. The one semi-cvlinder 17 is secured in position by
suitable screws 21. to lugs 22 unon the unner cap 19, and lugs 23 unon lamn
socket 12 and is further provided with a side opening 24. to receive the switch
action. Recesses 25 are made in the block 13 to accommodate the lugs 22 and 23.
The switch action consists of a square (or the like) spindle 26. at whose onter
end is the kev 26. hv which it may be nart rotated. Adioining the kev is a
screw collar 27, which takes into a screwthread in the beforenamed opening 24,
in the side of the one semi-cvlindrical cover 17. and by which it is secured thereto.
Next this collar and passing through an enlargement upon the spindle is a pin 28.
whose ends project from each side, so that they may (in rart rotation) more upon
the surface of a sliding cam 29, of what is known as the "hill and dale" type.

page_text: This cam is preferably stamped from sheet metal, and has two opposite gradual
rising and two opposite sudden drop, and two short flat surfaces. Upon these two
flat surfaces are formed stop projections 30, 30°. The said cam is free to rotate
upon the spindle, but such movement is governed by a projecting peg 131, upon
the periphery of the cam engaging with a slot opening 32, in the screw collar.
Forward of the cam and rart rotative with the spindle, is an insulated collar or
disc 33, upon whose front face is secured a metallic ring 34, such disc resting
against a coil spring 35. between it and the end of the spindle. Between the cam
and the disc there may if desired be a cushion like spring plate 36. Hence when
in its working position, by turning the key 26, the projecting pins 28, upon the
spindle ride up the gradual incline of the cam 29. until they reach the stops 30, 30*
and in so doing push the cam forward and with it the insulated disc having the
metallic surfaces, against the contact plates 16, 16°. By reversing the key rotation,
the whole of the parts carried upon the spindle are carried around for
a short distance permitted by the travel of the peripherical neg 31.
unon the cam 29. in the slot opening 32, in the screw collar 27.
Upon a further slight portion of rotation the pins 28. reach the inclines.
when the force of the coil spring 35, suddenly drives the cam back past the pins,
and of course the contact disc 33, with it. thus producing a sudden "break."
Reverting again to the porcelain block 13;-This consists of a circular base 37
having two vertical walls 38 and 39, the one 38 about diametrically across the
centre and the other 39. midway from such wall to the periphery, thus leaving the
one half side 40 flat. This flat side is placed opposite the switch action, and upon
its surface are secured the contact metallic segmental surfaces 16, 16ª one of
which 16. passes through the wall 38. to the wire connection 15, upon the other
side. while the other late 16. is carried downward to the plunger connection 41.
to the lamp. The other wire connection 14, is made to the shorter wall -39.
and thence downward to the other plunger connection 42, to lamp. Hence the
wire connections 14 and 15, are kept quite distinct and separated from the switch
mechanism.
The other semi-cylindrical cover 18, is now attached by a screw 43. and nut 44,
completing the general cylindrical form. Thus by the removal of this cover. the
wire connections can be readily made without any interference whatever with the
switch action while the lotter can also readily be removed if desired, by unscrewing
the collar from the other semi-cylindrical cover.
Having now rarticularly described and ascertained the nature of this my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:-
1. In an electrical switch the combination with the switch action mounted unon
a porcelain block 13. of the two part frame 17 and 18. part 17 heing attached to
ends 12 and 19. and part 18 secured by nut 44, all substantially as set forth and
shown and for the purposes specified.
2. In an electrical switch the combination therewith and employment of a
removable cover 18, giving access to the wire connections without interference
with the body or action of the switch, substantially as set forth and shown.
3. In an electrical switch the employment of the porcelain block 12, having the
diametric wall 38. and dividing wall 39, dividing off the wire connections from
each other and from the switch action substantially as set forth and shown in
the drawings.
Dated this 17th day of February 1899.
CHARLES T. POWELL,
Applicant's Agent.