Improvements in Electric Lamp Supports.
Year: 1899

page_text: Date of Application, 20th Nov., 1899-Accepted, 6th Jan., 1900
COMPLETE SPECIFICATION.
Improvements in Electric Lamp Supports.
I, HARRY LONG, Glass Mould Maker, of Greentown, in the County of Howard
and State of Indiana, United States of America, do hereby declare the nature of
my 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 supports for electric lamps, especially
lamps used for street lighting, and it has for its object to provide a simple means
for supporting a lamp and for raising and lowering it, and so arranged that
upon lowering the lamp the electric current will be automatically cut off, and
so that a person may change or insert carbons without danger.
I will describe an electric lamp support embodying my invention, and then
point out the novel features in the appended claims.
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 a sectional elevation of a support embodying my invention;
Figure 2 is a section on the line 2-2 of Figure 3;
Figure 3 is a section on the line 3-3 of Figure 2;
Figure 4 is a section similar to that of Figure 3, but showing the parts in a
different position;
Figure 5 is a section on the line 5-5 of Figure 3; and
Figure 6 is a partial elevation and partial section showing a modification.
Referring to the drawings, 1 designates a hollow post having at its upper end
a horizontally disposed arm 2, from which a tube 3 extends downward. Arranged
in the lower portion of the post 1 is a sprocket wheel 4 and a sprocket pinion 5.
The shaft of the pinion 5 is extended outward through an opening in the post
and is adapted to receive a crank 6, and on the pinion is a ratchet wheel 7 engaged
by a dog 8 to prevent a backward rotation of the pinion. The base of the post is
provided with a door 8* so that access may be had to the interior to adjust the
parts if found necessary. Engaging with the pinion 5 and also with the sprocket
wheel 4 is a sprocket chain 9, which extends upward through the post and over
idlers 11, 12 and 13 and thence through the tube 3 to a connection with the head
or upper portion 14 of an arc lamp.
Rigidly connected to the downwardly extended tube 3 is a receiving frame,
comprising a top plate 15 and a bottom ring 16, the top plate 15 and the ring 16
being connected by posts 17. The parts 15, 16 and 17 are preferably made in
one casting, and the part 15 has an interior screw thread to engage with the
screw thread of the tube 3.
Attached to the lamp and movable into and out of the receiver, is a head for
the lamp, comprising a ring-shaped plate 18, a ring-shaped bottom plate 19
and segmental blocks 20 arranged between the two ring-shaped plates. Fastening
bolts 21 pass through the ring-shaped plate 18, and blocks 20 and the ring-shaped
plate 19 and engage in the portion 14 of the lamp, as plainly indicated in
Figure 3. Between the blocks 20 and the plate 18 is a ring plate 22, and between

page_text: this plate 22 and the plate 18, I preferably place an insulating material 23,
consisting preferably of mica, and a mica insulation 24 is placed between the
lower ends of the blocks and the top of the plate 19. It will be noted that the
plate 19 has a downwardly extended flange 25, the purpose of which will be
hereinafter described.
Movable radially between the, blocks 20 are stop blocks 26, for the sake of
lightness these stops are preferably made hollow. The inner surfaces of the
stop blocks are inclined downward and inward as plainly indicated in Figures 3
and 4, and these inclined surfaces are provided with channels 27 having undercut
side walls to receive a dovetail rib 28 formed on the lower end of the conical
portion 29 of a tubular spreader 30. Upon a certain movement of the spreader,
as will be hereinafter described, it is designed to engage friction-tight with a
clamping ring 31 supported from the top plate 15, but having a vertical move-
ment relatively thereto. As here shown, bolts 32 extend from the clamping
ring upward through openings in the plate 15: The bolts 32 are provided with
heads to prevent them from passing entirely through the contracted lower ends
of the openings in the plate 15. The ring 31, as shown in Figure 3, is a split
ring so that it may yield to receive the upper, end, of the spreader..
Mounted to, swing on the ring 16 are supporting latches, 33, 34 and 35, each
latch being supported between lugs .36. cast integral with the ring 16, and the
pivot is so arranged that the inner end will overbalance the outer end, causing
the inner ends to swing downward under certain conditions. The outer, ends. 37
of the latches are beveled to engage a bevel portion 38 of the ring 16. to prevent
the latches from being swung too far outward. Main conducting wires 39, 40
lead through the post 1 and connect with the ring 16. The wires are insulated
from the ring, as clearly shown in Figure 3, and the ends are embedded in the
ring so that the upper surfaces of the wires are flush with the upper surface
of the ring. Preferably this portion of the wires will be flattened as indicated in
the drawings, and of course, the bare, wire will be exposed. This exposed portion
of the wire is designed to be engaged by circuit closing wires 41, 42 passing
respectively through the latches 33 and 34. When the latches are in their
horizontal position, the lower ends of the circuit closing wires 41, 42 will
engage respectively with the wires-39 and 40, and the upper ends of these circuit
closing wires will engage with exposed portions of the wires 43 and 44, attached
to the plate 22 but insulated therefrom. These wires 43 and 44 lead into the
lamp to supply a current to the carbons. A; hood 45 may be connected to the
tube 3 to protect the lamp from rain or snow....
:
"H 75.
In operation, when the lamp is suspended, the parts will be in the position
indicated in Figure 3, that is, the latches will be in a horizontal position with
the ring 22 resting thereon. Therefore it will be seen that these latches form
the support for the lamp. The current will pass through the wire 39, the wire 41
and the wire 43 into the lamp and then out through. the wires 44, 42 and 40;
of course; this order may be reversed. It will be noted that.when the lamp. is
suspended, the stop blocks 26 will be moved inward so as to permit the ends of the
latches to engage with the under side of the plate 22.
When it is desired to lower the lamp, it is first drawn upward by means of
the chain 9 and by this upward movement, the upper outer edge of the ring 19
engaging with the latches 33, 34 and 35 will swing said. latches upward,
immediately cutting out the current. This upward movement is to be continued
until the latches engage with the flange 25 of the ring plate 19, and, during, this
movement, the upper end of the spreader 30. will engage. with the clamping
ring 31 forcing the same upward until it engages with, the under side of the
plate 15.
As the parts are moved still further upward, the upper end of the
spreader will engage within the clamping ring and come to a stop, so that upon
further movement of the carrying head, the stop blocks 26 will be moved outward
so that their outer surfaces will be in vertical alignment with the edges of the
plates 18 and 19.

page_text: Now upon turning the gearing to lower the lamp, the several parts will move
downward, the frictional engagement of the spreader 30 with the ring 31 causing
said ring to also move downward. During this downward movement, the latches
will be prevented from turning downward or inward by engaging with the outer
surfaces of the stop blocks. When, however, the parts shall have been moved
sufficiently downward to engage the latches with the top ring 18, the ring 31
will be stopped by the heads of the bolts 32 and when the ring 31 comes to a
stop, the spreader 30 will also come to a stop, so that by a further downward
movement of the lamp-carrying head, the stop blocks 26 will be moved inward
to their normal position, and their inward movement may be limited by suitable
stops or pins.
When the lamp is again raised, the top of the plate 18 coming in engagement
with the inner ends of the latches will swing said latches upward where they
will remain until the blocks 26 are opposite the latches. At this time, the
latches will swing downward by gravity and support the lamp, as before
mentioned. A lug 46 (Figure 3) on the edge of the plate 18 is designed to engage
in a channel 47 fornred in one of the posts 17. This will guide the lamp. into the
supporting frame and also prevent any rotary movement of the lamp or its
carrying head while in position.
In Figure 6, I have shown a socket 48 for receiving an incandescent lamp 49.
Supported in the socket are the supporting latches 50 and 51, similar to the
supporting latches before described and also serving as circuit closers, that is,
wires extend through these latches for connecting the contact plates of the socket
To remove
with the contact plates connecting with the filament in the lamp.
the lamp from the socket, it is to be raised in the socket, so that the latches
by pressing upon their outer ends may be swung with their inner ends suffi-
ciently lifted to clear the flange 52 of the lamp. When it is desired to insert
the lamp, it is only necessary to push it upward against the inner ends of the
latches to swing the latches upward, and then by slightly lowering the lamp,
the latches will engage with the under side of the flange 52, as indicated in
Figure 6.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1. An electric lamp support, having stop blocks mounted to move outward
to prevent the supporting engagement of the latches with the lamp head, and
movable inward to permit the latches to support the lamp.
2. An electric lamp support, having stop blocks for the supporting latches, and
operating means co-acting with said stop blocks to move them inward and outward
by the vertical movements of the lamp head in the supporting frame.
3. An electric lamp support, having the supporting latches for the lamp head
constructed and arranged to, form circuit closers.
4. An electric lamp support, constructed and operating substantially in the
manner and for the purpose specified.
Dated this 20th day of November 1899.
A. M. & WM. CLARK,
Chartered Patent Agents, 53. Chancery Lane, London.