Improvements in connection with Electric Lamp Holders or Sockets.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in connection with Electric Lamp Holders or Sockets.
We, PERCY GARNISS EBBUTT and VERITY'S LIMITED, all of Plume Works,
Aston, near Birmingham, Electrical Manufacturers, do hereby declare the nature of
this invention to be as follows:.
:―
This invention relates to electric lamp holders or sockets and refers to the
terminals which are of the kind known as side-pinching or block type.
By our present improvements the said terminals are situated entirely on the
upper end of the interior or cylinder, that is to say, the end opposite to that in
which the plungers are fixed.
The object of this arrangement is to obtain an exceedingly high insulation,
there being no possibility of electrical leakage to the case which frequently
happens where the pinching screws are situated on the side of the cylinder as
hitherto, instead of upon the end according to our improved method.
The form of block or side pinching terminal may be varied according to
requirements, but preferably we employ a terminal formed from a piece of
rodding of a suitable section cut to the desired length and bored and tapped as
may be necessary to allow the wire to pass through one of the holes where it is
held in place by a screw screwing into a tapped hole which thus pinches the
wire against one side of the hole through which it passes.
In order to avoid any possibility of the terminals coming into contact with
the case, the said terminals are or may be sunk in deep slots, holes, or grooves,
formed in the upper end of the interior portion or cylinder or otherwise sunk
or recessed therein.
The two terminals are protected one from the other by means of a dividing
wall or rib on the said upper end of the interior or cylinder.
Dated this 7th day of December 1898
EDWD. J. PAYNE & SON,
Warwick Chambers, 104, Colmore Row, Birmingham,
Patent Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in connection with Electric Lamp Holders or Sockets.
We, PERCY GARNISS EBBUTT and VERITY'S LIMITED, all of Plume Works,
Aston, near Birmingham, Electrical Manufacturers, 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 reference.being had
to the drawings accompanying this specification and to the figures and letters
shewn thereon.
Our present invention relates to electrical lamp holders or sockets and refers

page_text: (a) to the terminals or contact pieces which are of the kind known as side-
pinching or block type & (b) to the positions they occupy upon the interior body
of china or other non-conducting material in the holder; the spring plungers
are preferably formed according to the arrangement shewn and described. The
interior part and its connections is enclosed within the ordinary metal casing of the
lamp holder.
Figure 1 represents a top plan of the china or other interior of non-conducting
material. Figure 2 represents plan shewing the terminals located in position.
Figures 3 & 4 are respectively under side plans of Figures 1 & 2. Figure 5
represents a vertical section. Figure 6 is an elevation shewing the circuit wires
attached. Figure 7 is another elevation. Figure 8 represents in side elevation
a terminal or contact piece of the kind we prefer to employ. Figure 9 is a plan
of same. Figure 10 an elevation of the spring plunger. Figure 11 is a plan of
the upper part or cylinder of same. Figure 12 represents in vertical
section the cylinder and plunger apart. Figure 13 is a sectional elevation of
cylinder and plunger shewing end view of terminal and the spring. Figure 14
shews in elevation the cylinder and plunger with terminal or contact piece.
Figure 15 represents in elevation the plungers or contacts and the upper contacts
with the wires attached.
By our present improvements the terminals or contact pieces A to which the
positive and negative wires A¹ are attached are situated entirely upon the upper
end of the china interior or body B that is to say upon the end opposite to
that in which the spring plungers or contact pieces C are fixed.
The object of this arrangement is to obtain an exceedingly high insulation,
there being no possibility of electrical leakage to the metallic case containing
the interior parts which frequently happens where the pinching screws are
situated on the side of the non-conducting interior part as hitherto instead of
upon the end according to our improved method. The form of block or side
pinching terminal can be varied according to requirements but preferably we
employ a terminal or contact piece A formed as shewn from a piece of rodding of
a suitable section cut to the desired length and bored and tapped as may be
necessary to allow the circuit wire A¹ to pass through one of the holes D where
it is held in place by a screw G screwing into a tapped hole horizontally which
thus pinches the wire against one side of the hole through which it passes.
Referring to the situation of the terminals or contact pieces A on the china
interior, in order to avoid any possibility of the terminals A coming into contact
with the metallic case of the lamp holder, the said terminals are or may be sunk
in deep slots recesses or holes E formed in the upper end of the china interior B
as shewn or otherwise sunk or recessed therein. The two terminals or contact
pieces A illustrated are preferably protected and separated the one from the other
by means of a dividing wall or rib F on the said upper end of the interior B.
An arrangement of spring plunger is shewn in connection with the terminals
though other suitable spring plungers may be used, the upper part (1) is formed
somewhat similar to a cartridge case and is either stamped from sheet metal or
bored out of the solid, the closed in end of same is drilled and tapped H to
receive a vertical holding down or fixing screw Hthe other or open end of the
cylinder part (1) is rolled or pressed over a shoulder I, on the spring plunger
part (2) after the parts have been placed in position.
We wish it understood that we can vary the general arrangements as to the
details herein more fully set forth to suit different requirements without departing
from the main principle of our said invention but,
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is:-
Firstly. In connection with electric lamp holders or sockets the combined
arrangements consisting of the particular construction and formation of the china

page_text: or other interior portion by forming deep recesses slots or holes upon the upper
end of same-viz.:-the end opposite to that in which the spring plungers are
carried locating the terminals or contact pieces to which the circuit-wires are
attached within said recesses slots or holes separating the recesses or slots and the
terminals the one from the other by a dividing wall or rib all constructed arranged
and operating for the purpose substantially as described.
Secondly. In electric lamp holders or sockets forming the terminals or contact
pieces of a section preferably such as shewn and bored and tapped as required for
the circuit wires to pass through each terminal and for the reception of the
fixing screw for the wire all in combination with spring plungers or contact
pieces contained within or carried by the china or other interior portion for
supplying contact with the lamp as and for the purpose described.
Dated this 5th day of September 1899.
EDWD. J. PAYNE & SON,
Warwick Chambers, 104, Colmore Row, Birmingham,
Patent Agents for the Applicants.