Improvements in Electric Incandescent Lamps.
Year: 1899

page_text: Date of Application, 9th Mar., 1899
Complete Specification Left, 5th Jan., 1900-Accepted, 9th Mar., 1900
PROVISIONAL SPECIFICATION.
Improvements in Electric Incandescent Lamps.
I, ANDREW HARTMAN MILLER, of 740, South 13th Street, Denver, in the County
of Arapahoe and State of Colorado, United States of America, Electrician, do
hereby declare the nature of this invention to be as follows:
This invention relates to an electric incandescent lamp, the filament of which
is actually or virtually in two sections, and is associated with such intermediate
and other connections as to permit of the filament or one or other section thereof,
to be cut in and out of circuit in a variety of ways, thus enabling the regulation
of the power of the lamp.
The one end of the filament is connected to the sheathing of the base whilst
the opposite end is connected to a spring contact finger in proximity to a switch
ring of insulating material adjustable circumferentially about the base and
carrying bridging contact pieces. The filament is whether virtually or actually
double or in two sections and is also connected to a third or middle leading in
wire common to both sections, that passes, through the base and terminates in
another similar spring contact finger in proximity to the switch ring. A third
spring contact finger similarly situated is connected by a wire passing through
the base with a central contact forming the positive pole, a fourth spring finger
being connected with the sheathing or negative pole..
By turning the ring the four spring fingers may be connected in two pairs or
two of them may be connected in various ways so as to effect three adjustments
for as many different candle powers viz., in one pair so as to connect the positivo
and negative terminals through the middle leading in wire and one section of
the filament; in two pairs so as to connect the positive terminal with the middle
wire so that the current passes through the two sections of the filament in
parallel for maximum candle power; or in one pair so as to make the current
pass through the two sections in series so as to produce a dimmed light owing
to the higher resistance.
The filament if of the ordinary single looped form would be connected
approximately at its middle with the third leading in wire, the adjustment and
operations being as above described.
Dated this 9th day of March 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London.
Пиргоѵешены смесете гncandescent Lamps.
I, ANDREW HARTMAN MILLER, Electrician, of 740, South 13th Street, Denver
in the County of Arapahoe and State of Colorado, United States of America, do
hereby declare the nature of this invention and in what manner the same is to
[Price 8d.1

page_text: be performed, to be particularly described and ascertained in and by the following
statement:
This invention relates to an electric incandescent lamp, the filament of which
is actually or virtually in two sections and is associated with such intermediate
and other connections as to permit of the filament or one or other section thereof,
to be cut in and out of circuit in a variety of ways, thus enabling the regulation
of the power of the lamp.
This specification is the disclosure of several forms of my invention, while the
claims define the actual scope of the invention.
Reference is to be had to the accompanying drawings forming a part of this
specification, in which similar characters of reference indicate corresponding
parts in all the figures.
Figure 1 is an elevational view of the invention;
Figure 2 is a sectional view on the line 2-2 of Figure 1;
Figure 3 is a sectional view on the line 3-3 of Figure 1;
Figure 4 is a sectional view on the line 4-4 of Figure 1;
Figures 5, 6 and 7 are diagrammatic views, illustrating three adjustments of
the connections;
Figure 8 is an elevational view illustrating a slight modification in the form
of the filament; and
Figures 9 and 10 are diagrammatic views showing two of the adjustments of
the form shown in Figure 8.
Referring to the first seven figures, my improvements may be adapted to a
base of the usual form, in which the positive pole is the contact 11, and in which
the negative pole is the metallic sheathing 12 of the base of the lamp. The base
of the lamp is formed with two annular ribs 14, between which is held to move
circumferentially an insulating ring 15, provided with two contact wires 16
and 17. This ring 15 may be turned around on the base to any position, so as to
effect the various adjustments of the lamp, as will be fully described hereinafter.
The lamp is provided with a double filament, the sections 18 and 19 thereof
being joined to a common leader 20, that passes up into the base and has electric
connection with a spring contact finger 21, on the base at a point directly beneath
the ring 15. The other end of the filament section 19 is connected with a
leader 22, that passes up through. the base of the socket and is electrically
joined to the sheathing 12 of the base. The end of the filament section 18 that
is not connected with the leader 20, is connected with a leader 23, which passes
up into the base and is electrically joined to a spring contact finger 24, similar
to the finger 21 and similarly situated. A leader 25 passes down from the
contact 11 and is electrically connected with a spring contact finger 26, similar
to the fingers. 21 and 24 and similarly situated. A fourth spring contact finger 27,
similar to those previously described, is connected with a leader 28, that passes
up into the base and is electrically joined to the sheathing 12. It will thus be
seen that there are four spring contact fingers 21, 26, 24 and 27, all of which
are arranged in the same circumferential line immediately below the ring 15,
so that various connections may be made between the spring fingers and the
contact wires 16 and 17. The contact fingers 21, 26 and 24 are insulated from
each other and from the sheathing 12 by any suitable means, such for example,
as insulating tape.
With this construction it is possible to effect three adjustments of the lamp,
by each of which a different candle power will be given forth. The adjustment
shown in Figure 5 is such as brings into play only one of the filament sections,
for example, the filament section 19. This adjustment is effected by turning
the ring 15 so that the contact wire 17 will bear between the fingers 21 and 20.
The current now entering from the positive contact 11, passes down the leader 25
and runs through the finger 26, contact wire 17 and finger 21, and from such
wire passes by the leader 20 into the filament section 19. From the section 19,

page_text: the current passes by the leader 22 to the sheathing 12 of the base. The adjust-
ment shown in Figure 6 is such as throws into circuit both filament sections in a
manner so that there is given forth the maximum power of the lamp. The
adjustment here is such as causes the contact wire 17 to engage between the
fingers 24 and 27, and the contact wire 16 to engage between the fingers 21
and 20. The current passing from the positive contact 11 runs through the
leader 25 to the contact finger 26, contact wire 16, and finger 21, and passes from
the finger 21 by the leader 20 to both sections 18 and 19 of the filament. The
current passes from the section 19 by way of the leader 22 to the sheathing 12
of the base; and the current passes from the section 18 by way of the leader 23
to the finger 24, contact wire 17 and finger 27, and from said finger 27 to the
sheathing 12 of the base through the leader 28. By this adjustment, that is,
that shown in Figure 0, both filament sections are employed to exercise the
maximum capacity of the lamp, which is due to the fact that the current is
divided and passes half through each filament section. Now that adjustment
shown in Figure 7 employs both filament sections but causes the current to be
passed wholly through both sections, thus offering a greater resistance to the
current and producing a dimmed light. In this adjustment the contact wire 17
is made to bear between the fingers 26 and 24, so that the current passing in
from the positive contact 11 flows through the leader 25 to the finger 20, through
the contact wire 17 to the finger 24, and from the finger 24 to the leader 23, to
the section 18, from the section 18 to the section 19, and from the section 19 by
the leader 22 to the sheathing 12 of the base.
It will thus be seen that by means of my invention three distinct adjustments
of the lamp may be attained and three distinct candle powers exercised. This
renders the lamp especially advantageous in hotels and hospitals where it is
desired to vary the power of the lamp, and since it is possible to adapt the
invention to the ordinary base, it is clear that the invention may be employed
without undue expense.
In Figure 8 there is shown a filament which is practically continuous and in
which there is not that marked division into sections as in Figures 1 to 7. In
Figure S the filament 29 is looped once within the globe and joined to the
leader 20 at approximately its middle. This form does not differ in any essen-
tiality from that previously described, the adjustment and operations being
practically the same. Figures 9 and 10 correspond respectively to the adjust-
ments shown in Figures 6 and 7. It is also possible, of course, to effect that
adjustment shown in Figure 5.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is—
1. In an electric incandescent lamp, the four contact fingers (21, 24, 26, 27)
whereof two (27, 26) respectively are permanently connected with the two poles
or terminals of the lamp, a third (24) is permanently connected with one end
of the filament, and the fourth (21) is permanently connected with the middle
of the filament whose other end is permanently connected with one of the poles
or terminals of the lamp. in combination with switches for effecting various
interchanges of connection between the said contact fingers, substantially as
and for the purpose specified.
2. The ring (15) turning on the base of the lamp and having contacts (16, 17)
arranged to effect various connections of the contact fingers (21, 24, 26, 27).
A! M. & WM. CLARK,
Chartered Patent Agents, 53, Chancery Lane, London