Improvements in Electric Switches.
Year: 1890

page_text: Date of Application, 9th Sept., 1890-Accepted, 25th Oct., 1890
COMPTELE STECIMATION.
Improvements in Electric Switches.
I, CHARLES GEORGE PERKINS, of 302 Asylum Street Hartford, County of Hartford
and State of Connecticut, United States of America, Invontor, 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 relates to improvements in Electric Switches and its object is to
produce a switch in which the make and break shall be practically instantaneous, and
in which the contact shall be always good and certain. Moreover, I have designed
a switch in which all the parts are replaceable and at the same time have given it a
compact structure whereby valuable space is saved. The principle of my switch is
that of storing power during the initial movement thereof, and afterwards releasing
the power to effect the quick movement of the contact parts. The moving contact
pieces are mounted on a block of the insulating material in such a manner as to be
pressed outward by springs within the block. This causes the contact pieces to
make spring contact with the line posts, which are arranged in a circle about the
block. As the movement is a rotary one, a wiping contact is also effected. The
block is loosely mounted on the main shaft and is recessed to receive a diamond-
shaped piece also loose on the shaft. There is lost motion both between the diamond
and the block and between the shaft and the diamond, the connection between the
two last named parts being made by means of a slot and a pin. The diamond stands
between two strong springs, which, as soon as the lost motion between the shaft and
the diamond is taken up, resist the turning of the handle. To relieve the friction, a
pair of rollers are set into the points of the diamond. In this way very strong
springs may be used, and instantaneous makes and breaks can be obtained.
The whole is handsomely mounted on a porcelain vase and the working parts are
inclosed by a cover. A special feature of novelty is the use of removable handles,
all switches of the same capacity being supplied with similar handles. Ordinarily
the handles will be removed and kept in the possession only of authorized persons.
This will prevent the danger of malicious or mischievous interference with the switches
by persons having no right to handle them.
I have illustrated my invention in the accompanying drawings, in which :-
Figure 1 is a plan of my switch with a part of the cover removed.
Figure 2 is a side elevation of the same.
Figure 3 is a plan with the cover wholly removed, showing the position of the parts
when the circuit is closed.
Figure 4 is a section along the line 4-4 in Figure 3.
Figure 5 is an end elevation and part section of my switch.
Figure 6 is a plan showing the position of the moving parts just before the springs
pass into control.
Figure 7 shows the same parts after the springs have done their work.
The drawings represent a double pole switch with four line posts, A, A', B, and B'.
These posts are arranged upon a base P of porcelain in such a manner that their
curved inner surfaces are in a circular line. Within the circle thus formed is a
block, I, loosely mounted upon a suitable shaft, E. The shaft itself passes through
the centre of the porcelain base and turns freely therein. Projecting from the
posts A and B are strong rods or pins J, which are bent down and enter the porcelain
base, within the circle already referred to. The block I is cut away at opposite sides
for a considerable distance, formning a long notch at either side, which notches are
limited at each end by the solid portions of the block ii. The rods J, or at least the
vertical straight portions thereof, stand within the notches and serve as detents for
limiting the movement of the block in one direction or the other. The block I, is

page_text: made preferably of porcelain, but it may be made of honsilatu or any other good
insulating material.
On those parts of the periphery of the block 1, which are not cut away, are contact
pieces (0, which are provided with lips or flanges e c, which run back into grooves
in both the upper and lower surfaces of the block. The grooves are usually lined
with metallic pieces de to prevent wear. The contact pieces CC are acted upon by
springs DD, which are coiled in cavities or openings in the blocks 1, and press tho
said contact pieces outward.
Now the contact preces described make electrical connections on the one side
between the posts A and A4, nud on the other side between the posts B and B' when
the parts are in the position illustrated in Figure 3. In the reversed position of the
parts (as shown in Figure 1) the connection referred to is broken. "In either case
the contact pieces are spring pressed, and as the reversal of the switch takes place
by a partial rotation, a wiping contact is secured in addition to the spring contact.
Thus, good electrical connection is assured.
On the shaft Eis mounted loosely a diamond-shaped piece F which enters an
irregular opening in the block 1. The piece F has at the top a slot, in which
plays a pine in the shaft E. In the points of the diamond are mounted "rollers a a,
the outer surfaces of which project beyond the diamond points or edges. The shape
of the irregular openings is such that it will allow a considerable lost motion to the
diamond F. The latter will, however, finally strike against the edges of the opening
and carry the block with it on a further movement. This will be apparent from an
inspection of Figure 6. It will also be clear from the same Figure and others that
there will be considerable lost motion between the shaft E and the diamond F before
the pine passes from one side of the slot, to the other. Outside the diamond
and normally pres-ing upon two of the straight sides thereof are springs G (³, which
are held in slots in the upper ends of two standards g g on the base. Figure 5 shows
the manner in which the ends of the springs are supported. The springs are
ordinarily sprung into position, and are held in place by pressure. It will be seen
that the tops of the slot walls on the inner side overhang slightly the ends of the
spring GG to prevent their slipping out.
Referring now to Figure 3, it will be seen that the contact pieces are so placed
as to close the circuit. In order to break the circuit it is necessary to turn the shaft E
in the direction of the curved arrow. This is accomplished through the medium of
a handle H, which is pressed over the spring outer end of the shaft E, and catches by
means of slots ³ h' over the opposite ends of the pin h, which traverses the shaft.
The first part of the movement takes up the lost motion between the pine and the
sides of the slot, unless it be already taken up as shown in Figure 3. The diamond
is then moved forward and spreads the springs G G until they are finally brought into
the position illustrated in Figure 6. By this time the diamond will have taken the
lost motion between itself and the block (the points of the diamond having passed
from one to the other of the opening ) so that any further movement of the diamond
will carry the block with it. But when such further movement is caused by turning
the handle, the latter loses control of the movable parts, which then pass under the
influence of the spring G G. These close together as soon as the diamond has
passed beyond the line of centres and throw both the diamond and the block together
with the contact pieces on the latter. This, of course, takes up both lost motions, as
shown in the detail views at the right on Figure 6.
The object of the rollers is to make the friction as light as possible.
The end of the shift is split so as to form a spring for holding the handle Hin
place when such handle is needed. Ordinarily, however, the handles will be removed
and kept only by authorized persons. I make the handles of all switches of the
sume capacity similar in size and shapo, so that the handle of one will fit
any other.
At K is shown a cover with a slot al k for slipping over the pin h. After
pussing over the pin the cover has to be rotated a little so as to bring a notch on
the lower edge of it over a projection on the base p. If now the handle_H_ bø

page_text: put on, it will stand in such a manner that it will point either toward the word
"OFF" (see Figure 1) or to a point ninety degrees therefrom marked "ON." An
operator will therefore know in which direction he must turn the switch in order
to reverse it.
In Figure 5 are shown lateral openings pp in the base P, and also a vertical
opening p in the said base. These are for the admission of the line wires. The
last named opening communicates with a cylinder opening in one of the binding
posts B. Positive connection is made at the post by means of the screw b. The
construction at all the posts is the same.
It is evident that by the construction described I secure a very quick make and
break of the electric circuit. It is also evident that any one of the parts described
can easily be replaced if it should becouse lost or broken."
The foregoing shows clearly that the action of operating the switch consists first
in storing power in the springs G G and afterwards releasing the springs, whereupon
the stored-up power does the work of effecting a quick make or break.
I desire to call attention to the fact that the contact pieces are not strictly
circular, but are flattened or indented at the middle, as clearly shown in the drawing.
If this were not so, it might happen that the corner of the binding post A', for
example, might press upon the middle of the contact piece as the latter was passing
the said corner, and might so affect the bearing of the further end of the contact piece
upon the post A as to make it uneven and so cause burning. This is especially
liable to be the case since the middle of each contact piece is pressed outward by a
spring.
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:
1. In an electrical switch, a rotably mounted spindle a contact block, loosely
mounted thereon and a pin or its equivalent fixed therein, in combination with an
intermediate loose angular piece, the said angular piece and block being provided
with devicos whoroby the angular piece engages with both the pin and the block, as
and for the purpose set forth.
2. In an electrical switch, a rotably mounted spindle, a contact block, loosely mounted
thereon, and a pin or its equivalent fixed therein a loose angular piece, the said
angular piece and the block being provided with means for engaging with each other
with loose motion, in combination with a spring or springs, adapted to play upon the
sides of the angular piece, as and for the purpose set forth.
3. In an electrical switch, contact devices and a cover therefor, a central operating
shaft projecting through the cover, a detachable handle for the shaft, and a spring
connection between the handle and the shaft, as and for the purpose set forth.
4. In an electric switch, contact making and breaking devices and a cover
therefor, a central opening, a split shaft and a pin traversing it, and a handle
adapted to slide on over the shaft, the handle being noticed to fit over the said pin
as described.
5. In an electrical switch, an insulating plug or holder carrying one or more
contact plates loosely attached to the outside thereof, and one or more springs which
press the contact plute or plates away from the plug or holder, in combination with
one or more contact pieces co-operating with the spring-pressed plate or plates, as
set forth.
6. In an electric switch, an operating shaft, a contact plug loosely mounted
thereon, an angular block also loosely mounted on the shaft, the plug having an angular
opening larger than but co-operating with the said block, and a pin in the said shaft
located in a slot in the angular block, all in combination with one or more springs
pressing against the side of the block, as set forth.
7. The combination with switch devices mounted on a suitable base, of cover for
the said switch devices, a shaft projecting through the said cover, a handle on the
said shaft, the said cover being provided with words or characters for indicating

page_text: reversed positions of the switch devices, and also being provided with a notch which
engages with a projection on the base for keeping the covor in the right position for
making the correct indications, as set forth.
8. In an electric switch, the combination with a rotary contact, plug, a spring-
pressed contact plate, carried thereby and a pair of contact posts co-operating with
the said plate, the said plate being centrally flattened or indented as set forth.
9. In an electric switch, a rotary contact plug and a spring pressed contact plate,
mounted on the periphery thereof in combination with lips projecting from the said
plate toward the centre of the plug and grooves within which the said lips are
adapted to slide, as set forth.
10. In an electrical switch, an operating shaft, a loosely mounted contact plug
carried thereby, and an angular block capable of being moved by the said shaft,
the said angular block being pressed upon by one or more springs and having
a roller or rollers in its operating end or ends for relieving the friction as
set forth.
11. In an electrical switch, a contact plug loosely mounted on a shaft, and an
angular block on the same shaft, a spring or springs pressing upon the said angular
block, and a roller or rollers in the bearing end or ends of the said block as
set forth.
12. An electric switch, substantially such as described.
Dated this 9th day of September 1890,
CHARLES G. PERKINS.
By his Agents,
Horn & Son.