Improvements in Electrical Switches.
Year: 1898

page_text: PROVISIONAL SPECIFICATION.
Improvements in Electrical Switches.
ARTHUR VERNON GIFKINS & FREDERICK ROBERT HILL, Electrical, Mechanical &
Hydraulic Engineers, 68, Victoria Street, Westminster, London, S.W., do hereby
declare the nature of this invention to be as follows:-
This invention has for its object to provide a switch of the class wherein the
movable contact is constituted by metal plates or-laminations and has for its
object to provide a switch which is readily and cheaply made and in which a very
perfect self adjusting contact is obtained and which can readily be adapted to
carry any desired current.
According to this invention the plates which constitute the movable contact
are mounted in a carrier and distance pieces are placed between the plates so
as to leave spaces between the said distance pieces. The plates and distance
pieces pass through an opening or openings in the carrier which can conveniently
consist of a piece of metal bent into form, the bent portion being the end to
which the plates are applied by being passed through openings in opposite sides
of this shaped carrier near to the bend thereof, and the ends or legs of the
piece being mounted upon an axis provided with a loose handle and a spring
for rapidly removing the contact plates when it is operated by the said handle to
break the circuit.
The contact plates and distance pieces are held in place by means of a screw
or bolt passed through the end of bend of the piece and through holes in the
plates and distance pieces and into a screwed nut at the opposite side of the series
of plates. The holes in the plates through which this screw passes are elongated
or enlarged so as to allow the plates lengthwise play so that-they can adjust
themselves between the fixed contacts on which their respective ends bear. The
proper adjustment is therefore readily effected by passing the said plates con-
stituting the movable contacts between the fixed contacts before the plates and
distance pieces are firmly clamped together by means of the screw or bolt so that
the plates if not in correct position will move lengthwise to that position and
then, by tightening up the screw or bolt, the plates and distance pieces are firmly
clamped together. The plates are curved in such a way that the tightening of
the screw tends to straighten them so that by this means the distance between
their ends can be lengthened and the movable contact be thus adjusted to com-
pensate for wear and to give a good rubbing and firm contact with the fixed con-
tact pieces. By making each plate of a standard size and thickness to carry
a prearranged number of amperes the switch can readily be adapted for

page_text: carrying any desired current by simply fitting the requisite number of the said
plates.
COMPLETE SPECIFICATION.
Improvements in Electrical Switches.
ARTHUR VERNON GIFKINS and FREDERICK ROBERT HILL, trading as Hill,
Gifkins & Co., of 68, Victoria Street, Westminster, S.W., Electrical and
Mechanical Engineers, 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 has for its object to provide a switch of the class wherein the
movable contact is constituted by metal plates or laminations and has for its
object to provide a switch which is readily and cheaply made and in which a very
perfect self adjusting-contact is obtained and which can readily be adapted to
carry any desired current.
According to this invention the plates A, which constitute the movable contact
are mounted in a carrier B, and spring distance pieces C, preferably of steel are
placed between the plates so as to leave spaces between the outer parts or ends
of the said plates which extend beyond the said spring distance pieces. The contact
plates and spring distance pieces pass through an opening or openings D, in the
carrier B, which can conveniently consist of a piece of metal bent into form,
the bent portion being the end to which the plates are applied by being passed
through openings D, in opposite sides of this shaped carrier, near to the bend
thereof and the ends or legs of the piece being mounted upon an axis provided
with a loose handle and a spring for rapidly removing the contact plates when it
is operated by the said handle to break the circuit.
The contact plates and distance pieces are held in place by means of a screw
or bolt E, passed through the end of bend of the piece and through holes
in the plates and distance pieces and into a screwed nut F, at the opposite side of
the series of plates. The holes G, in the plates through which this screw E,
passes are enlarged or preferably elongated so as to allow the plates lengthwise
play so that they can adjust themselves between the fixed contacts or terminals H,
on which their respective ends bear. The proper adjustment is therefore readily
effected by passing the said plates constituting the movable contact between the
fixed contacts before the plates and distance pieces are firmly clamped together
by means of the screw or bolt so that the plates if not in correct position will
move lengthwise to that position and then by tightening up the screw or bolt
the plates and distance pieces are firmly clamped together. The contact plates
are bowed or curved in such a way that the tightening of the screw tends to
straighten them so that by this means the distance between their ends can be
lengthened and the movable contact be thus adjusted to compensate for wear and
to give a good rubbing and firm contact with the fixed contact pieces. By making
each plate of a standard size and thickness to carry a pre-arranged number of
amperes the switch can be readily adapted for carrying any desired current by
simply fitting it with the requisite number of the said plates.

page_text: Having now particularly described and ascertained the nature of our said in-
vention and in what manner the same is to be performed we declare that what
we claim is:-
:-
1. The independent self adjustment of the contact plates.
2. The form of contact plate as described in conjunction with spring distance
plates.
דיד