Year: 1887

page_text: Date of Application, 18th Apr., 1887
Complete Left, 18th Jan., 1888
Complete Accepted, 18th May, 1888
I, JOHN HENRY HOLMES, of 67, Westgate Road, Newcastle on Tyne, in the County
of Northumberland, Electrical Engineer, do hereby declare the nature of this inven-
tion to be as follows :-
"
This invention relates to improvements in electric switches or apparatus for making
and breaking electric circuits, and has for its object to ensure the making and
breaking of the circuit being effected rapidly even though the handle used to cause
the switch to be operated be moved at a slow rate of motion. To this end I arrange
the switch in such a manner that the movable conducting contact piece which makes
and breaks the electric circuit is urged into either the " on or the "off" position
solely by the force of a spring or equivalent, and is not moved by direct pressure
exerted through a rigid portion of the handle. The force of the spring is exerted
between the handle and the contact piece, and not between the base of the switch and
the contact piece; and the direction of the force exerted by the spring upon the
contact piece is altered by moving the handle round its axis in either direction.
As the handle approaches the end of its traverse it passes a dead point, and the
strong force exerted through the medium of the spring on the movable contact piece
changes its direction and rapidly urges the contact piece in a direction to close the
circuit if open, or to open the circuit if closed.
The handle and the contact piece are both pivotted, and the arrangement is such
that they constitute a pair of pivotted levers with a spring pressure tending to draw
or move the levers together in either of the two directions, so that when one of these
levers is moved by the operator through a sufficient distance, the direction of the
force which the spring exerts will be changed so as to draw or move the other lever
over to the same side.
The spring as I prefer to apply it is arranged so that it is always exerting some

page_text: force on the contact piece in order to prevent the contact piece remaining stationary
in any intermediate position between the extreme limits of its travel.
Suitable stops can be provided to limit the strokes of the handle and prevent its
being moved in a wrong direction-Also stops to arrest the contact piece. As will
be evident, apparatus to operate on the principle of my invention as above set forth
may be constructed in various forms; and in lieu of employing a spring, an equivalent
device, such as a weight with cord, or a piston in a cylinder containing air, might be
employed, but usually it will be found preferable to use a spring.
W. LLOYD WISE,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Making and Breaking Electric
Circuits.
I, JOHN HENRY HOLMES, of 67 Westgate Road, Newcastle on Tyne, in the County
of Northumberland, Electrical 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 improvements in that class of electric switches or apparatus
for making and breaking electric circuits, constructed so as to ensure the making and
breaking of the circuit being effected rapidly even though the handle used to cause the
switch to be operated be moved at a slow rate of motion and in which to this end the
switch is arranged in such a manner that the moveable conducting contact piece which
makes and breaks the electric circuit is urged into either the " on or the "off"
position solely by the force of a spring, and is not moved by direct pressure exerted
through a rigid portion of the handle. In such switches the force of the spring is
exerted between the handle and the contact piece, and not between the base of the
switch and the contact piece ;-and the direction of the force exerted by the spring
upon the contact piece is altered by moving the handle round its axis in either
direction.
As the handle approaches the end of its traverse it passes a dead point, and the
strong force exerted through the medium of the spring on the moveable contact piece
changes its direction and rapidly urges the contact piece in a direction to close the
circuit if open, or to open the circuit if closed.
The handle and the contact piece are both pivotted, and the arrangement is such
that they constitute a pair of pivotted levers with a spring pressure tending to draw
or move the levers together in either of the two directions, so that when one of these
levers is moved by the operator through a sufficient distance, the direction of the force

page_text: which the spring exerts will be changed so as to draw or move the owner lever over to
the same side.
The spring is arranged so that it is always exerting some force on the contact piece
in order to prevent the contact piece remaining stationary in any intermediate position
between the extreme limits of its travel.
Suitable stops are provided to limit the strokes of the handle and prevent its being
moved in a wrong direction. Also stops to arrest the contact piece. Apparatus to
operate on the principle above set forth is according to my invention constructed in
various forms, as I will hereinafter explain, premising that in lieu of employing a
spring, an equivalent device, such as a weight with cord or a piston in a cylinder
containing air might be employed, but usually it will be found preferable to use a
spring.
Referring to the accompanying three sheets of drawings
Figs. 1 and 2 shew a switch according to this invention for breaking an electric
circuit at one point.
A is the base, B the handle turning on the pivot C, D the moveable conducting
contact piece, also on the pivot C; E the spring, F one terminal of the circuit and
G the other, H H are stops. The spring E is a flat spring fixed at one to the contact
piece at L, this part being raised to allow for the play of the extremity of the spring,
which rests on one of two faces J and K on the end of the handle. Fig. 1 shews
the handle and contact piece in the positions which they occupy when the electric
circuit is completed the current passing from the stationary bar F to the terminal G
through the contact piece D. When the handle is turned from the position shown
in Fig. 1 to that shown in Fig. 2 the spring is bent outwards by the angular shaped
portion or cam formed by the faces J and K. So long as a perpendicular drawn
from the face of the spring, where it meets the angle falls to the right of the centre
of the pivot C the contact piece D is impelled toward the terminal G but when the
perpendicular falls to the left of the centre, the contact piece is impelled in the
opposite direction, and when the force is sufficient it makes its stroke suddenly and
rapidly, coming into the position shown in Fig. 2 when both the contact piece and
the lever are held firmly against their respective stops H. Fig. 2 shews the position
of the parts when the circuit has been thus broken. It will be seen that except
when the switch is being operated the contact piece is held firmly against the stop H
or the stop G by the spring and cannot be jarred away. The stops allow a larger
range of movement to the handle than to the contact piece for the purpose of enabling
the direction of the force of the spring to pass a dead point as the handle approaches
the end of its traverse in either direction, and thus allow the spring to act upon the
contact piece so as to urge it into the other of its two stationary positions to that
which it occupied when the handle commenced its stroke. Figs. 3 and 4 shew a
switch similar to that illustrated in Figs. 1 and 2 except that the spring E is upon
the handle instead of on the contact piece, and the faces J, K, are on the contact
piece instead of on the handle.
In the switch shown in Figs. 5 and 6 the handle B has two arms B¹ B² between
which is held the flat spring E. This spring presses alternately on the two faces J
and K at the end of the moveable contact piece D. When the handle is turned from
the position shown in Fig. 5 to that shewn in Fig. 6 the spring, acting on the face J,
first presses the contact piece against the terminal G. It then comes to the dead
point, and afterwards presses on the face K, moving the contact piece suddenly and
rapidly up to the stop H (Fig. 6).
In Figs. 7 and 8 there is a double or sugar tongs spring E E on the handle, and
two sets of faces J J and K K on the movable contact piece. The action is practically
similar to that of the switch shewn in Figs. 3 and 4 except that the two springs act
concurrently.
Figs. 9 and 10 shew an arrangement of switch according to this invention in which
a helical spring working in compression is used. This spring E is placed in a cavity
in the handle B, and is covered by a cap or cover M. The cap has a flat face N,
which takes in succession against the faces K, J, formed on the end of the movable
'

page_text: contact piece. As the handle is turned in the direction of the arrow the cap M is forced
into the hollow of the handle, compressing the spring until it (the handle) is sym-
métrically situated with regard to the two faces K, J; when it has reached this
position, the spring expands exercising a pressure on the face J which causes the
contact piece suddenly to move towards and up to the stop H.
In the arrangement shewn in Figs. 11 and 12 the spring is carried in the movable
contact piece, and the faces J, K are on the handle. The action is practically similar
to that of the arrangement shewn in Figs. 9 and 10.
Figs. 13 and 14 shew a switch according to this invention in which the making
and breaking are performed by pushing a handle in a straight line, and not by
turning it around a centre. The handle B slides in guides B B₁, mounted on the
base A. At or near its centre is a socket or recess in which is received a helical
spring E. The mouth of the recess is closed by a cap M, which is free to slide within
the recess, and which partly encloses the spring. On the top of the cap is an ogival
shaped nipple or projection N which slides in contact with the similarly shaped end
of the movable contact piece C. When the handle is pushed to the right (Fig. 13)
the projection N must recede partly within the recess in the handle, until its point
has passed the point at the end of the contact piece. The spring M will then force
out the cap M, and the projection N acting on the right side of the end of the
contact piece will force the latter into the position shewn in Fig. 14-and will hold
it there.
In the arrangement shewn in Figs. 15 and 16 both the handle and the contact
piece move in straight lines parallel to each other, and the circuit is broken at two
points F and G. The movable contact piece carries two fingers or prongs F¹, G¹,
which, when the circuit is complete, fit into the fixed contact pieces and G.
The pointed head of the nipple or projection N of the cap M slides against the
projection on the movable contact piece D forcing it to the right or left according
as it is on one side or other of its centre.
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 I do not claim broadly
the combination in an electric switch of an actuating mechanism, a separately moveable
conducting contact piece and a spring or equivalent exerting its force between a point
or points forming part of the actuating mechanism and a point or points forming part
of the contact piece and not directly connected to the base plate or other immoveable
portion of the switch, the said parts being so arranged that the direction of the force
exerted by the spring upon the contact piece when in one of its stationary positions
is altered as the actuating mechanism approaches the end of its traverse and after
passing the dead point the force acts upon the contact piece so as to urge it into the
other of its two stationary positions, and suitable stops that are rigidly connected to
the base plate or other immoveable portion of the switch, for the purpose of limiting
the strokes of the actuating mechanism and the contact piece and of preventing the
actuating mechanism and the contact piece being moved in a wrong direction; but
what I claim is :-
My improved electric switches substantially as described with reference
respectively to and illustrated in Figures 1 and 2, Figs. 3 and 4, Figs. 5 and 6,
Figs. 7 and 8, Figs. 9 and 10, Figs. 11 and 12, Figs. 13 and 14, and Figs. 15 and 16,
of the accompanying drawings whether made as single or multiple contact switches.
Loro4 TAR
LOUDI
5034
JOHN H. HOLMES.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.