Year: 1889

page_text: A communication from HARRY T. PAISTE, of 1206, Chestnut Street, Philadelphia,
Pennsylvania, United States of America, Electrical Engineer.
I THOMAS SPENCER of 18 Warwick Street, Regent Street, in the County of Middle-
sex, Electrician, 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:-
The object of this invention is to construct an electric switch by which the circuit
can be instantly made or instantly broken, to prevent what is termed sparking, and
furthermore, to so construct the switch that it will be impossible for the operator to
control the making or breaking circuit of the arm after it reaches a certain point in
its revolution.
In the accompanying drawings:-
Fig. 1 is a perspective view of this improved switch with part of the casing broken
away.
Fig. 2 is a plan view, with the casing in section.
Fig. 3 is a transverse section on the line 1-2, Fig. 2.
Fig. 4 is a horizontal section showing the circuit completed.
Fig. 5 is a horizontal section showing the circuit broken.
Fig. 6 is a perspective view of a detached part of the device; and
Fig. 7 is a view of the switch in its simplest form.
A is the base plate, on which the switch mechanism is mounted, and B is the
casing which covers the working parts. 1) is the terminal plate of one of the electric
wires, and is U-shaped in form, having two sides d, d' connected by a segment of a
circled, the whole being partially covered by a cross-plate and the side d turning
slightly inwards as shown. The plate D is preferably struck up from one piece of
metal.
.

page_text: C is the terminal plate of the other wire, c being the binding post for the terminal C,
and being the binding post for the terminal D.
A vertical shaft E has its bearings in the cross-plate of the terminal D, and is
provided with a suitable handle F, preferably of non-conducting material, and situated
between a shoulder on this shaft and the handle is a non-conducting washer f, which
insulates the case B from the working parts of the device.
Mounted at the lower extremity of the shaft E is a cross-head G, having depending
pivot pins y, g, on which are pivotted two levers I, I³ of the form shown clearly in
fig. 6, the short arms i, i of the levers being connected by a coiled spring J, the long
arms of the levers having flat faces j, j¹.
When the circuit is to be completed the handlo F is turned so that the two faces j,j¹
of the lovers will assume the position shown in fig. 4, that is, the face of one of the
levers resting upon the terminal D, while the face of the other lever rests upon the
terminal C, whilo if the circuit is to be broken the handle is turned so that the levers
will assume the position shown in fig. 5, the faces of both levers bearing against the
terminal D and being clear of the terminal C.
When it is desired to turn the levers from the position shown in fig. 5 to the
position shown in fig. 4, the levers remain in contact with the terminal B until the
ends of the levers are moved to the position shown by dotted lines in fig. 5, in which
position the plate D is tangent to the arc of a circle traversed by the end of the long
arm of the advance lever, and consequently, said levor will be actuated by its spring,
the end of the long arm of the lover moving with a sliding contact along tho straight
face of the terminal D, and gradually increasing in speed, so as to finally fly from the
plate D to the plate C so rapidly as to preclude sparking.
As the end of the terminal plate D is practically at right angles to the terminal
plate C, it will be impossible to move the shaft back, as the end of the long arm of the
fever will bear against the terminal plate D.
When in the position shown in fig. 4, the current passes directly from the terminal C
to the terininal D, through the long arm of the lever, making connection at that point,
and it also passes from one terminal to the other through the medium of the two lovers
and the cross-head carrying the same. The latter, however, is the main circuit, the
direct contact between the two terminals being simply used to give a better connection,
and this connection being broken as soon as the handle is turned, so that all the cur-
rent then follows the other course until finally cut off, when the parts assume the
position shown in fig. 5.
When the parts are in the position shown in fig. 5, the lug on the end of the side
plate of the terminal I prevents any revorso movement of the handle F, as the and
of the long arm of the lever will press directly against this lug 6, the spring tending
at all times to keep the face of the lever against the terminal D.
In fig. 7 is shown, in place of the two lovers a shaft provided with one lever only,
the lever in this instance having a spring J' mounted on its pivot and bearing against
a pin on the short arm of the lever, which tends to keep the long arm of the lever
always against either the terminal D or C. In this instance, the circuit will pass
directly from the toriminal D through the lever to the terminal O.
Having now particularly described and ascertained the nature of this said invention
and in what manner the same is to be performed, as communicated to me by my
foreign correspondent, I declare that what I claim is :-
1. The combination of a switch shaft, an arm thereon, a spring lever carried thereby,
and a terminal having a portion tangential to the pivot of the lever, whereby the free
arm of said lever has a sliding contact with the tangential portion of the terminal
during that portion of its movement which is due to the action of the spring, all sub-
stantially as specified.
2. The combination of a U-shaped terminal such as D, and a flat terminal such as
placed across the open end of the U-shaped terminal, with a switch shaft having an
arm, a contact lever pivotted to said arm, and a spring acting on said lever and serving
to move the same independently of the arm, all substantially as specified.

page_text: 3. The combination of the U-shaped terminal, and the straight terminal, a shaft
having a cross-head, and two levors such as 1, I' pivotted thereto and connected
together by a spring, each lever having contact faces for bearing upon the terminals,
substantially as described.
4. The combination of the U-shaped terminal having a lug such as b³, with a straight
terminal such as C and the shaft and spring lever for completing the circuit between
the terminals C, D, substantially as described.