Improvements in Holders for Electric Incandescence Lamps.
Year: 1894

page_text: Date of Application, 5th Feb., 1894
Complete Specification Left, 5th Nov., 1894-Accepted, 2nd Feb., 1895
PROVISIONAL SPECIFICATION.
Improvements in Holders for Electric Incandescence Lamps.
I, RICHARD FRANCIS RANDELL of Stanhope Street, Birmingham in the
County of Warwick, Manufacturer, do hereby declare the nature of this invention
to be as follows:—
My invention has reference to holders for electric incandescence lamps and its
chief object is to provide a simpler, handier and more efficient method of attaching
the lamp to the holder.
According to my invention instead of securing the lamp to the holder by a
bayonet joint or by hooks (requiring the addition of a strong spring to steady the
lamp) which are the two methods that have been hitherto generally adopted I
secure the lamp to the holder by means of a pair of spring jaws which grip the
usual collar or ring on the neck of the lamp, these jaws being attached to the holder
in such a position relatively to the parts for making contact with the contact pieces
on the lamp that when the lamp is in the grip of the jaws the contact with these
pieces is ensured. The gripping faces of the jaws are of such a curve or contour
that when closed upon the lamp neck they correspond or approximately so with the
circular form of the neck. In order to ensure proper adjustment of the lamp so
that the contacts on the holder may not touch the insulating material in the neck
instead of the contact pieces thereon, as now sometimes happens, I form the jaws
each with a hole or recess to receive respectively two studs or projections on the
lamp collar such for example as the studs used for attaching incandescence lamps
by the bayonet joint method. The spring jaws have tails or finger pieces extending
to any convenient places for opening them when a lamp has to be attached or
removed; in removing a lamp it is only necessary to open the jaws with one hand
and the lamp will drop out into the other. The spring jaws will receive and hold
any incandescence lamp no matter what is the diameter of the neck and therefore
the difficulty sometimes met with of the lamp neck being too large or too small to
fit the holder is obviated.
My holders are preferably constructed internally as follows:-A plate or base of
porcelain or other insulating material having a central aperture for the passage
of the two wires carries two binding screws.
These screws respectively bind the ends of the two wires and also the ends of two
metallic springs so that these two springs respectively make contact with the two
wires. Each spring has a metallic piece projecting therefrom so as to come in
contact with the corresponding contact piece on the lamp neck when the lamp is
held by the spring jaws. The plate or base above mentioned is recessed to give
room for play of the springs. A plate or base for the lamp is screwed or otherwise
attached to the first named plate or base and has a hole or holes for the passage
the metallic pieces that project from the springs. The support for the spring jaws
may be fixed to the plate or base for the lamp but is preferably fixed to a shade of
metal or other material which is itself secured to the said plate or base concentrically
with the lamp.
of
1004
J. C. MEWBURN,
55 and 56, Chancery Lane, London, Chartered Patent Agent

page_text: improvements in Holders for Electric Incandescence Lamps.
1, RICHARD FRANCIS RANDELL of Stanhope Street, Birmingham in the
County of Warwick, Manufacturer, 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 has reference to holders for electric incandescence lamps and its
chief object is to provide a simpler, handier and more efficient method of attaching
the lamp to the holder.
According to my invention instead of securing the lamp to the holder by a
bayonet joint or by hooks (requiring the addition of a strong spring to steady the
lamp) which are the two methods that have been hitherto generally adopted I
secure the lamp to the holder by means of a pair of spring jaws which grip the
usual collar or ring on the neck of the lamp, these jaws being attached to the holder
in such a position relatively to the parts for making contact with the contact pieces
on the lamp that when the lamp is in the grip of the jaws the contact with these
pieces is ensured. The gripping faces of the jaws are preferably of such a curve or
contour that when closed upon the lamp neck they correspond or approximately so
with the circular form of the neck. In order to ensure proper adjustment of the
lamp so that the contacts on the holder may not touch the insulating material in the
neck instead of the contact pieces thereon, as now sometimes happens, I form
the jaws each with a hole or recess to receive respectively two studs or projections
on the lamp collar such for example as the studs used for attaching incandescence
lamps by the bayonet joint method. The spring jaws have tails or finger pieces
extending to any convenient places for opening them when a lamp has to be attached
or removed; in removing a lamp it is only necessary to open the jaws with one
hand and the lamp will drop out into the other. The spring jaws will receive and
hold any incandescence lamp no matter what is the diameter of the neck and there-
fore the difficulty sometimes met of the lamp neck being too large or too small to fit
the holder is obviated.
Figure 1 of the accompanying drawings is a side view partly in section of a
holder constructed in accordance with my invention in its most approved form; the
lamp being in such position relatively to the holler that the contact pieces on
the lamp are in contact with those on the holder. Figure 2 is a side view of the
same holder but with the lamp drawn away from the holder so that the contact
picces are out of contact. Figure 3 is a plan of the underside of the same holder.
a is a plate or base of porcelain, wood or other insulating material fixed in a
metal ring or frame band having a central aperture c for the passage of the
wires d d. These wires are secured by the two binding screws ee which are screwed
respectively through two metal pieces ff into the plate a. g is a screw cap to the
plate a and ring b. h is a shade of metal or other suitable material secured against
the under edge of the ring 6 by means of a screw ring i. The ring has a vertical
groove and the inner edge of the shade a projection to engage with the said
groove so that the shade and the parts it carries may always be maintained in the
same axial position relatively to the ring & and plate a; the proper adjustment of
the contacts to each other is thus ensured. kk are a pair of jaws pivotted on a rod
or pin fixed to the underside of the shade ; these jaws are fitted with a spring m
which tends to keep them closed. n is a screw stud taking into the lower end of
the rod and p is a spring fitted on the said rod between the stud n and the jaws k
so as to force the jaws upwards. The jaws are each formed with a hole (or recess)
to receive respectively two studs or projections 9 7 on the lamp collar s.
The jaws
have tails or finger pieces for opening them and are capable of swivelling on
their rod or pivot I clear of the holder as indicated in dots in Figure 3.

page_text: .
When it is desired to secure a lamp in the holder the jaws k k are opened to
receive the lamp collar and then allowed to close upon it care being taken that
the studs 99 enter the recesses in the jaws in order to ensure that the usual contact
pieces on the upper face of the lamp neck may come against the heads of the binding
screws e e which in the lamp shown in Figures 1, 2 and 3 constitute the contact pieces
on the holder. The spring p by forcing up the jaws and consequently the lamp
ensures that contact shall take place. When it is desired to remove the lamp it is
only necessary to open the jaws kk and the lamp will drop out. When securing the
lamp in the jaws it is well to temporarily turn the jaws into the position shown in
dots in Figure 3, and in order to effect this turning movement before and after
securing the lamp the jaws should be drawn somewhat downwards as seen in
Figure 2 so as to clear the screws e e. This capability of swivelling of the jaws
away from the centre of the holder is also of great advantage when "wiring."
Figures 4 and 5 illustrate a modification in which instead of the screws e e
constituting the contacts on the holder, the holder contacts consist of two metallic
springs tt which are secured by the binding screws ee and other screws ele¹ between
the metal pieces ff and the plate or base a.
Figure 6 illustrates in vertical section another modification in which the jaws k k
are vertical instead of horizontal. They are pivotted on pins in a block v and their
tails rr are sufficiently heavy to keep the jaws closed upon the lamp collar (or the
jaws may be kept closed by means of suitable springs). w is a spring which presses
the plate a downwards so as to ensure that the holder contacts shall always be
pushed down upon the lamp contacts.
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 in respect of holders for electric incandescence lamps is :-
1. A pair of jaws to grip the collar or ring on the lamp neck these jaws being
attached to the holder in such a position relatively to the parts for making contact
with the contact pieces on the lamp that when the lamp is in the grip of the
jaws the contact with the said pieces is ensured, substantially as hereinbefore
described.
2. In combination with jaws arranged as and for the purpose referred to in
Claim 1, a spring on the rod or pin on which the jaws are pivotted the said spring
ensuring the necessary contact between the contact pieces, substantially as
hereinbefore described with reference to Figures 1, 2 and 3.
3 Arranging jaws employed as and for the purpose herein before described so
that they can swivel on their pivot as and for the purposes herein before set forth.
4. Constructing holders for electric incandescence lamps as hereinbefore described
and shown in the accompanying drawings.
Dated this 5th day of November 1894.
J. C. MEW BURN & ELLIS,
55 and 56, Chancery Lane, London, Patent Agents.