Improvements in Combined Electrical Switches and Lamp Holders.
Year: 1899

page_text: Date of Application, 23rd Mar., 1899-Accepted, 29th Apr., 1899
COMPLETE SPECIFICATION.
Improvements in Combined Electrical Switches and Lamp Holders.
I, ROBERT FREDERICK HALL, of Ferndale, Church Road, Moseley, near the
City of Birmingham, Engineer, 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; —
This invention relates to electric lamp holders of the type which have com-
bined with them a switch arrangement to enable users to turn on or off the
supply of current to each separate lamp, and has for its object to improve the
construction of, and means for operating, such lamp holder switches and to
provide for the interposition of an insulating medium between separate contacts
when the switch is in the "break" position.
According to my invention I provide within the interior of a suitable
lamp holder casing a series of three blocks of insulating material, the upper
and lower ones of which are fitted in such a manner as to be incapable of rotating
and are respectively provided with vertically lignable pairs of spring plungers
or contacts, those of the upper block being in electrical connection with the
circuit or lead wires and those of the lower block are arranged to contact against
the terminal plates of the lamp filament, whilst the third and intermediate
block, which is located in between the other two, is capable of a rotatory move-
ment and is also provided with a pair of contact pieces which extend through
its thickness, and are adapted to be brought either into line with the upper and
lower sets of spring contact pieces and thus make through electrical connection
between them, or be taken out of connection therewith for breaking the circuit,
and which operations are performed by rotating the said block by means of a
small thumb lever extending through a slot in the casing.
Figure 1 of the accompanying drawings represents an elevation of my improved
switch lamp holder.
Figure 2 is a topside plan thereof.
Figure 3 is a complete vertical section of the holder and switch showing the
parts in the positions they assume when the circuit is made by the solid metal
conductors in the rotating switch piece being brought into line and contact with
the two separated sets of plungers fitted to the upper and lower blocks.
Figure 4 is a cross section of Figure 3 upon the dotted line a.
Figure 5 is a similar vertical section to that of Figure 3, but showing the switch
piece turned round through a quarter rotation so as to bring its conductor pieces
out of line and contact with the lead wire and lamp terminal plungers.
Figure 6 is a cross section of Figure 5 upon the dotted line a¹.
Figure 7 is another vertical section of the switch lamp holder but taken upon
the dotted line Figure 5 in a direction at right angles to those of Figures 3
and 5 and showing the parts in the positions in which they are placed for switch-
ing off current from the lamp.
The same letters of reference indicate corresponding parts in the several figures
of the drawing.
a is the outer metal casing of the holder which is of greater length than usual

page_text: and may be made up of top and bottom parts a¹, a², connected together by a
union ring b. Into the upper part a', I fit the top block of porcelain or other
insulating material c, which may be prevented from rotating by indenting part of
the metal of the casing inwardly into corresponding grooves in the block. Into
suitable separated holes c in this block, I fit a pair of connections d, in which
the lead wires d' terminate and from which a pair of spring or other plungers e,
proceed with their lower ends e', extending through holes e, in the bottom of the
said block so as to project a short distance into the intermediate space f, con-
taining a loose rotatable switch block g, and having embedded within it a pair
of conductor wires or circuit makers g, g³, whose upper ends g³, extend above
the top of the rotary block and are adapted to make contact with the ends e',
of the plungers e, whilst their lower ends g, extend in like manner slightly below
the bottom of the switch block for coming into electrical connection with a pair
of contacts h¹, let into the material of the lower non-conducting block h, which
is prevented from rotating within the casing by similar means as the top one and
is provided with a pair of spring plungers h², for bearing upon the filament
terminals when a lamp is connected to the holder.
kis a cord grip device, which is drawn down onto the top of the block c
and around an extension c, of it with the lead wires gripped between them, by
means of a flanged coupling k', screwing onto the outer casing, whilst in order
to provide for the rotation of the switch block for taking its conductor pieces
into and out of line with the upper and lower sets of contacts for making or
breaking the circuit, I provide the same with a small thumb lever m, connected
by screwing or otherwise and extending through a slot b, made through the
union ring 6, of such a length as will admit the necessary rotation of the block,
i.e. through a quarter of a revolution, being made. A second lever or handle n,
is screwed to the said ring near to the end of the slot, and when the contact is
to be broken, the two levers are pressed together by the thumb and finger which
causes the switch block to move from the position represented in Figures 3
and 4 to that represented in Figures 5, 6 and 7, in which the upper and lower
contact pieces are perfectly insulated from one another by the interposed thick-
ness of insulation provided by the said switch block, whilst to again complete
the circuit and cause the current to flow to the lamp, the said levers are opened
out or moved apart, thus returning the switch block to the "make" position
shown in Figures 3 and 4 with its conducting pieces bridging and providing a
straight line connection between the respective, negative and positive contacts
of the upper and lower blocks, which said pairs of contacts are in exact vertical
line with one another, and each individual contact is perfectly insulated by the
surrounding non-conducting material within which it is fitted. A spring or
springs may be arranged in conjunction with the rotatory block to give a fly
action or augment the rotation for breaking or making the circuit.
I wish it to be understood that I do not confine myself to any particular form
or arrangement of lead wire connections and also that the pair of contacts pro-
ceeding from such connections and the other pair which come against the filament
terminals of the lamp may also be of any suitable construction and further that
the means for imparting a rotatory or other movement to the intermediate or
switch block and immovably securing the other top and bottom blocks within
the lamp holder casing may be varied without departing from my invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First In combined electric lamp holders and switches, the employment of a
movable or rotating block of non-conducting material having directed through it,
a pair of separated metallic conductors, which are adapted to be brought in line
with upper and lower sets of plungers or contact pieces to make the circuit and

page_text: out of line with such contacts to break the circuit, substantially as described and
set forth.
Secondly-A combined electric lamp holder and switch consisting of a casing
Irovided at top and bottom with fixed blocks of insulating material each fitted
with a pair of spring plungers or contact pieces which are respectively in electrical
connection with the circuit lead wires and the lamp filament, and an intermediate
rotating or movable block or switch piece, provided with a pair of metallic con-
ductors adapted to be brought into and out of line with the upper and lower sets
of contact pieces, substantially as and, for the purpose described and set forth.
Dated this 22nd day of March 1800
ROBERT FREDERICK HALL,
By Henry Skerrett,
24, Temple Row, Birmingham, Agent for Applicant.