Improvements in Holders for Incandescent Electric Lamps.
Year: 1888

page_text: Date of Application, 15th June, 1888
Complete Specification Left, 27th Feb., 1889
Complete Specification Accepted, 4th May, 1889
PROVISIONAL SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
:
We, WALTER ROWBOTHAM and WILLIAM Fox both of 39 Lever Street Manchester,
in the county of Lancashire, Electricians do hereby declare the nature of this
invention to be as follows:-
Our invention relates to holders for incandescent electric lamps or burners.
According to our invention we prefer to form the holders for capped lamps, of a
tube, of sufficient internal diameter to admit the cap of the lamp, closed at the lower
end; with a disc of insulating material, fitted to the inside of the tube after the
manner of a piston, and pressed toward the mouth of the tube by a spiral spring,
fitting close in the tube, the spring bearing at one end against the base of the tube,
and at the other end against the bottom face of the insulating disc. The insulating
disc is pierced in the centre to allow the leading wires to pass through, and
carries two screw studs to receive the ends of the wires, said studs being in such a
position as to bear against the plates on the base of the lamp, when the lamp is in
the holder.
In each of the opposite sides of the tube is cut a straight slot, extending from a
short distance from the top to near the bottom, and a second slot is cut, in an oblique
direction, from the top, to meet the first slot a little distance from its end, so that, on
the trunnion pins on the lamp caps being passed into the second slot and the lamp
pressed downward, the slot causes the lamp to make a slight movement sideways;
and, on the pressure being removed, the trunnion pins fall into the ends of the first
slots, locking the lamp in position. A guide pin is inserted into each side of the
insulating disc, projecting into the first slots, to prevent rotation of the insulating
disc. In holders of base loop lamps, we prefer to use spring hooks in place of the
said screw studs, and provide a screw to receive the wires, and we also omit the
second slot and cut a third in an oblique direction, from the bottom of the first,
upwards, or turn the first slot in a semicircle and cut the third slot straight upwards,

page_text: from the bottom of the first slot, the remainder of the holder being the same as
described, the lamp being then hooked on to the said spring hooks and the side
pins pressed down until past the end of the third slot, and released, when the pins
fall into the second slot and lock the lamp in position.
Dated this Fourteenth day of June 1888.
COMPLETE SPECIFICATION.
Improvements in Holders for Incandescent Electric Lamps.
WALTER ROWBOTHAM of 25 & 27 Sidney Street Salford Electrical Engineer and 11
WILLIAM Fox of 25 & 27 Sidney Street Salford Electrician 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 :—
Our invention relates to holders for incandescence electric lamps or burners.
Referring to accompanying drawing-
Figure 1 is a side elevation and Figure 2 is a section of our improved Holder.
According to our invention we prefer to form the Holders for capped incandescence
lamps of a tube A Figures 1 and 2 closed at one end; a disc of insulating material B
Figure 2 is fitted, after the manner of a piston, to the inside of the tube, and is
pressed toward the mouth of the tube by a spiral spring C, fitting close in the tube A, 20
bearing at one end against the base of the tube, and at the other end, against the
bottom face of the insulating disc B. The insulating disc B is pierced in the centre
to allow the leading wires to pass through and carries two screw studs D D to receive
the ends of the wires-said studs being in such a position as to bear against the ..
plates on the bottom of the lamp, when the lamp is in the holder; in each of the 2
opposite sides of the tube is cut a slot E Figs. 1 & 2 extending from a short distance
from the top to nearly the bottom & a second slot F is made, in an oblique direction,
from the top to meet the first slot E a little distance from its end, so that on the
trunnion pins on the lamp cap being passed into the second slot F and the lamp -
pressed downward, the slot causes the lamp to make a slight movement sideways & on 3
the pressure being removed, the trunnion pins fall into the end of the first slot E
locking the lamp in position. A guide pin G is inserted into each side of the insulating
disc to prevent rotation. The lamp is removed by giving it a slight downward
pressure to bring the trunnion pins out of the slot E & then turning in the reverse.
direction to the slot F causing the lamp cap to leave the Holder entirely.

page_text: Having now particularly described and ascertained the nature of our said Inven-
tion and in what manner the same is to be performed we declare that what we
claim is
First A Holder for incandescence electric lamps in which the spring causing
contact is entirely free from carrying currents of electricity substantially as
described.
Second A Holder for incandescence electric lamps in which the formation of the
slot is as illustrated substantially and for the purposes described.
Third A Holder for incandescence electric lamps substantially as described and
illustrated.
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