Improvements relating to Electric Incandescence Lamps, and to Adapter Fittings therefor.
Year: 1896

page_text: Date of Application, 8th Jan., 1896
Complete Specification Left, 8th Oct., 1896-Accepted, 2nd Jan., 1897
Improvements relating to Electric Incandescence Lamps, and to
Adapter Fittings therefor.
1, REUBEN JAMES BOTT, of No. 9 Park Place Villas, St. Mary's, Paddington,
London, Electrical Engineer, do hereby declare the nature of this invention to be
as follows:-
This invention relates to electric incandescence or glow lamps and to adapter
fittings there'or.
With lamps of this kind or class as heretofore made, it has been usual to provide
a separate or independent switch (which has, in some cases, been mounted in the
lamp-holder) whereby the current may be switched on or off as required. Such
switches add considerably to the cost of the lamp fittings and, when mounted in
the lamp-holder, on account of their small size, need to be very accurately made in
order to be efficient.
Now according to my said invention I attach to the lamp itself very simple and
efficient means for switching the current on or off, so that I am enabled to effect
the desired result in most cases, without in any way modifying the construction of
existing lamp-holders made without switches, or in other words, I am enabled, by
my said invention, to adapt the lamp when fitted in a lamp-holder made without a
switch, to be used for switching on and off the current.
For this purpose I provide one or more tubular pieces or sleeves capable of
rotatably connecting the lamp to the lamp-holder so that, by turning the lamp
relatively to the said holder, the contacts on the lamp-cap may be moved into and
out of engagement with those of the holder and the circuit or circuits through the
lamp thus made and broken.
'
In carrying my said invention into practice according to one form, I provide
around the cap of the lamp, a sleeve or collar capable of turning freely thereon,
suitable means being provided, such as a rim or flange on the cap of the lamp, to
prevent, the removal or detachment of the said sleeve or collar. In the case of a
lamp for use in a bayonet holder the said sleeve is provided with the usual side pins
to enter the shots in the lamp-holder and engage therewith so as to press the lamp
against the spring contact plungers. With this arrangement, by turning the lamp
within the said sleeve or collar, the contact plates on the lamp-cap may be moved
into and out of engagement with the contact plungers or buffers of the lamp-holder
and the current thus switched on or off.
The contact plates on the lamp-cap should be of such form as to leave sufficient
space between them, in the "off" position, to clear the ends of the plungers or
buffers and ensure that the circuit shall be properly broken. If desired, in order
to ensure that the lamp be turned into its proper "on" and "off" positions,
I provide projections or slots or recesses on the lamp-cap, which engage with
projections or slots or recesses on the loose sleeve or collar, so that, under the
action of the spring plungers or buffers of the lamp-holder, the said sleeve or collar
will, when turned, come to rest in its "on" or "off" position enly, and cannot be
easily left in an intermediate position. Other suitable means, such as forming an
undulating path at the end of the lamp-cap, for the ends of the spring plungers or
buffers, may also be adopted for this purpose.

page_text: I sometimes provide the lamp-cap with suitable projecting pieces whereby it
can be conveniently turned in the sleeve or collar without taking hold of the
bulb.
I preferably make the surface of the lamp-cap bearing the contact plates, of
porcelain, or other insulating material capable of withstanding the rubbing action
of the buffers in turning on and off the lamp. In some cases moreover 1 form
grooves in the end surface of the lamp-cap to guide the said plungers and prevent
spreading of the same.
My said invention may also be applied to other forms of lamp-holders such as
"screw-socket " lamp-holders, in which case the screw forms the loose sleeve or
collar which is preferably provided with a flange or milled rim at its lower or outer
edge to enable it to be easily screwed into the socket; in this form the inuer collar
with the usually central-contact must be placed ercentrically within the loose
collar or sleeve so as to enable the circuit to be made and broken as the lamp is
turned in the said sleeve or collar. This form of holder may be also provided with
devices similar to those above mentioned for determining the "on" and "off"
positions of the lamp.
In making "adapter" fittings according to my said invention, I am enabled, if
desired, to obviate any modification of the ordinary lamp-cap. For this purpose
the said adapter consists of two tubes or sleeves attached together so as to be
capable of turning relatively to one another. One of these tubes or sleeves
receives the cap of the lamp, and the other or second tube engages with the lamp-
holder. The said second Lube is also provided internally with a conductor or
conductors which engage with the contacts in the lamp-cap, so that, by turning one
of the two tubes relatively to the other, the current to the lamp may be switched
on and off as in the arrangements above mentioned, similar accessory parts and
modifications being applicable thereto.
Moreover the adapter can be connected by flexible conductors with the lamp
instead of being connected directly therewith as above mentioned.
It is obvious that ny said invention may be applied for other purposes, for
example, it may be used in connection with multiple-filament lamps for throwing
one or more of the filaments thereof into circuit in any desired manner. My said
improvements may also be used in connection with lamps, such, for example, as
those described in the specifications accompanying my Provisional Applications
for Letters Patent dated 15th October 1895, No. 19275 and 31st October 1895,
No. 20600 in which the end or cap is formed of glass.
Deted the 8th day of January 1806
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements relating to Electric Incandescence Lamps, and to
Adapter Fittings therefor.
I, REUBEN JAMES BOTT, of 10 The Avenue, Bruce Grove, Tottenham, in the
County of Middlesex, late of No. 9 Park Place Villas, St. Mary's, Paddington,
London, 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:-
My invention relates to electric incandescence or glow lamps and to adapter
fittings therefor.

page_text: According to one part of my said invention I provide the lamp itself with very
simple and efficient means whereby, when the lamp is used with the ordinary
bayonet-joint holders or sockets, the switching of the current on or off can be
effected by simply turning the lamp about its axis without turning any part of the
holder or socket, so that I am enabled to effect the desired result without the
necessity for any alteration or modification in the construction of such holders or
sockets.
For this purpose I provide one or more tubular pieces or sleeves loosely fitted on
the lamp so that the latter is free to turn therein, and whereby the lamp may be
connected to the bayonet-joint holder or socket in such a manner that, by turning
the lamp alone about its axis relatively to such tubular piece or sleeve, the contact-
pieces on the lamp-cap can be moved into and out of contact with those of the
holder or socket, and the circuit or circuits through the lamp thus made and broken.
My said invention also comprises other improvements hereinafter described.
In the accompanying drawing I have shown how my said invention may be
conveniently and advantageously carried into practice :-
Figure is a side elevation, partly in vertical central section, showing an
incandescence lamp constructed according to my present improvements, and
Figure 2 is a side elevation of the loosely fitting sleeve or collar thereof
detached.
Figure 3 is a development of the said sleeve or collar.
Figure 4 is a side elevation, partly in vertical central section, showing a slight
modification of my invention.
Figures 5 and 6 are similar views illustrating the application of my invention to
lamps having a glass cap.
Figure 7 is a section on the line, t, Figure 6, and
Figure 8 is a vertical central section of one form of alapter fitting having my
improvements applied thereto.
Like letters indicate corresponding parts throughout the drawing.
Referring to Figures 1 to 4. A is the bulb of the lamp; B is the metal cap
thereof; is the loosely fitting sleeve or collar, which is provided with pins or
studs D adapted to enter the bayonet-slots of an ordinary holder or socket E for
the purpose of securing the lamp thereto. The cap 13 is sometimes provided at its
upper part with a projecting rim F, which may be of metal as shown in Figure 1,
or may be formed on the porcelain or other insulating material in which the contact
plates G are fixed, as shown in Figure 4. H indicates the spring plungers or
contacts of the holder or socket.
It will be seen that, by turning the lamp about its axis through a suitable angle
in the loosely fitting sleeve or collar C, the contact plates G can be moved out of
contact with the plungers H of the holder and the filament thus put out of circuit;
and by continuing or reversing such movement of the lamp the filament can be
again put into circuit, and these operations can be performed without turning any
part of the holder or socket.
By forming the rim F on the insulating material in the metal cap B, a higher
insulation resistance is obtained between the said cap and the contact-plates G than
would otherwise be obtained.
The metal cap B shown in Figure 1 is provided with one or more projections K,
and suitable notches or recesses C, C are formed in the upper edge of the loosely
fitting sleeve or coliar C, so that, when the contact plates G are in contact with
the plungers H, the said projections K will rest in the notches or recesses C,
and when the lamp is turned so as to nove the plates G out of contact with
It will
the plungers H, the said projections will enter the recesses C.
be seen that the pressure of the spring buffers or plungers H keeps the
projections Kat all times in contact with the upper edge of the sleeve or
collar C; therefore, in order to turn the lamp in either direction, the springs
of the plungers H must be compressed thereby, and as soon as the projections K
arrive at the next notches or recesses they will be forced into the same by

page_text: the reaction of the springs. The movement of the lanp into either its "on"
or its "off" position is thus facilitate and the risk of its being left in au
intermediate position is reduced to a minimum. Other suitable means may,
however, be employed for this purpose, for example suitable projections may he
made on the inner surface of the sleeve C, the said projections being adapted to
spring into corresponding depressions in the surface of the cap B, or, if desired,
the depressions may be made in the sleeve or collar C and the projections on
the cap B.
I sometimes provide the lamp-cap B with a suitable projecting rim or flange or
with finger-pieces whereby it can be conveniently turned in the sleeve or collar
without taking hold of the bulb,
In applying my invention to incandescence lamps having the cap male of glass,
such for instance as those described in the specification accompanying my former
application for Letters Patent dated 31st October 1895, No. 20,600, I arrange the
loosely fitting sleeve or collar C in the groove M formed around the glass cap, as
shown in Figure 5, the said sleeve or collar being either put in position during the
manufacture of the cap, or being sprung on after the glass cap is formed, or it may
be secured in position by providing the pins D with inward extensions which
project into the groove M and prevent the removal of the said sleeve.
suitable devices may, however, he employed for this purse. In the arrangement
shown in Figure 5, the contacts G of the lamp-cap are let into recesses A', and
may consist of white or other suitable metal fused to the leading-in wires J,
or of plates or other contacts soldered or otherwise fastened to the said leading-in
wires.
Other
In Figures 6 and 7 I have shown another modification of my invention, in which
the loosely fitting sleeve or collar C is made as a spring clip of the shape indicated
in Figure 7, the pins D being arranged to engage with the bayonet-slots of the
holder E from the outside, instead of from the inside as in the arrangement shown
in Figure 1, and the said collar being sprung over the said holder. The said pins D
also serve to secure the collar C to the lamp by entering the groove M in the
glass cap thereof.
I sometimes apply my loosely fitting sleeve or collar provided with the pins or
stads to a casing or other support in which the lamp-bulb is enclosed or to which
the lamp-bulb is attached in any convenient manner.
Figure 8 shows my lousely fitting sleeve or collar C provided with the pins D
applied to an adapter fitting. The fitting shown is designed to receive the ends
of conductors leading to a lamp-s:andard, a motor or other electrical apparatus to
be supplied with current. The said adapter fitting may, however, be so
constructed that the lamp can he attached directly to it.
It is obvious that my said invention may be differently applied; for example, it
may be used in connection with multiple-filament lamps or with adapter fittings
for supplying several lamps, for the purpose of throwing one or more of the
filaments or lamps into circuit in any desired manner, the number el contact-plates
being varied accordingly.
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 :-
First. An electric incandescence or glow lamp adapted to be connected with a
bolder or socket by a bayonet-joint and so constructed that, by turning it about
its axis, the filament or filaments can be put into and out of circuit as desired,
without turning any part of the holder or socket.
Secund. The combination, with an electric incandescence or glow lamp, of a sleeve
or collar fitted loosely thereon and adapted to be connected by a bayonet-joint with
a holder or socket, substantially as hereinbefore described and for the purposes
specified.
Third. The combination, with the lamp-cap, of the sleeve or collar fitted loosely

page_text: thereon and adapted to be connected by a bayonet-joint with a holder or socket,.
and suitable means for retaining the said cap in different positions relatively
to the said sleeve or collar, substantially as and for the purposes above
specified.
Fourth. The electric incandescence or glow lamp having my improvements
applied thereto substantially as described with reference to Figures 1, 2 and 3.
or to Figure 4 of the accompanying drawing, for the purposes specified.
Fifth. The modification of my invention whereby I adapt the sanie to lamps
provided with glass-caps substantially as described with reference to Figure 5,.
or to Figures 6 and 7 of the accompanying drawing.
Sixth. An adapter fitting constructed according to my said invention substan-
tially as described with reference to Figure 8 of the accompanying drawing.
Dated this 7th day of October 1896.
REUBEN JAMES BOTT.
D. Young & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.
REUBEN JAMES BOTT.
D. Young & Co.,
11 & 12 Southampton Buildings, London, W.C.,.
Agents for the Applicant.