An Improvement or Improvements in the Method of Ensuring a Quick Break in Electrical Switches, Known as the "Knife" Switch, "Chopper" Switch, or "Hatchet" Switch.
Year: 1896

page_text: Date of Application, 3rd Oct., 1896-Accepted, 30th Jan., 1897
COMI LELE DICITIATION.
An Improvement or Improvements in the Method of Ensuring a
Quick Break in Electrical Switches, Known as the "Knife"
Switch, "Chopper" Switch, or "Hatchet" Switch.
I, GEORGE HERBERT VERITY, of Plume Works, Aston, in the County of
Warwickshire, 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:-
My invention consists of the hereinafter described improvement in electrical
switches, of the form known as the "knife" the "chopper," or the "hatchet "
switch, for the purpose of ensuring a quick break. It has hitherto been found
impossible to obtain a quick break in switches of the type referred to, thereby
rendering them liable to set up an electric arc and to fuse the contacts of the
switch; this defect, it is the object of my invention to overcome.
According to my invention the brush or contact maker of the "knife,'
"chopper" or "hatchet" switch, is carried closely parallel to the handle bar by
means of a spindle in connection with a spring affixed to or in the said handle bar.
By so arranging the said parts, in breaking circuit the brush does not commence
to leave the contacts, until the handle bar is already some distance from the
contacts, when the spring, which is now in compression, comes into action and
completes the breaking of the circuit instantaneously and independently of the
action of the hand.
I will now proceed to describe my invention with reference to the accompanying
drawing.
Fig. 1, is a side elevation of one form of a "knife," "chopper" or "hatchet'
switch, made according to my invention.
Fig. 2, is a plan of the same switch.
"
Figs. 3, and 4, are sections of parts of the same switch taken upon the lines as
indicated on the plan Fig. 2.
The same letters of reference indicate the same parts in the several figures of
the drawing.
A is the slate or other non-conducting base or block.
B represents the cable sockets or terminals, into which the cables or electric
wires are soldered.
C represents the cables or electric wires soldered in the cable sockets or
terminals B.
D represents the clip contacts which receive the brush or contact maker E when
closing or completing the circuit.
E represents the brush or contact maker.
F represents the handle bar, which carries the brush or contact maker E.
G represents a box or recess in handle bar F containing the spring M and
spindle N. The said spring becomes compressed upon the handle bar F being
raised, and if the upward movement is continued, causes a quick breaking of the
circuit, even if the movement of the handle bar be a slow one.
H represents the handle for raising and depressing the handle bar F.
represents a screwed cap fitting end of box or recess G.
J represents a stop pin, and Ka stop catch or foot, the latter catching on the

page_text: former and preventing the handle bar being thrown too far backward, but keeping
it at a convenient angle. In the case of change over switches made in accordance
with this invention the stop J and catch foot K would be omitted.
L represents the contact carrier.
M represents the spring and N the spindle the action of which is described under
the reference to the box or recess G.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, 1 declare that what
I claim is :--
1. The use of a spring to cause a "quick break" independently of the action of
the hand, in switches of the type known as the "knife" switch, "chopper" switch,
or "hatchet" switch.
2. The combination of a spindle and spring to cause an independent "quick
break" in switches of the type known as the "knife" switch, "chopper" switch
-or "hatchet" switch.
3. The use of a spindle and spring enclosed in a box or recess in the handle bar
of a switch known as the "knife" switch, "chopper" switch, or "hatchet" switch,
for the purpose mentioned and substantially as described.
Dated this 26th day of September 1896.
GEORGE HERBERT VERITY.