US638705A - Electric switch. - Google Patents

Description

No. 638,705. Patented Dec. l2, I899. J. l GREVELING.

ELECTRIC SWITCH.

licatio' (No Model.)

UNITED STATES PATENT QEEI cE.

JOHN L. OREVELING, OF NEW YORK, N. Y.

ELECTRIC SWITCH.

SPEGIFICATION forming part of Letters Patent No. 638,705, dated December 12, 1899.

Application filed January 24, 1899. Serial No. 703,246. (No model.)

To aZZ whom, it may concern:

Be it known that I, JOHN L. CREVELING, of New York, in the county of New York, State of New York, have invented certain new and useful Improvements in Electric Switches, of which the following is a complete specification, reference beinghad to the accompanying drawings.

The object of my invention is to produce an electric switch of compact form that is adapted to carry a current of comparatively high amperage and voltage.

Under certain conditions of use.-as, for example, in heating cars by electricity-itis not only necessary to employ such a current, but it is also of considerable practical importance to employ for such service a switch that occupies but small space. In red ucing the size of the switch it is necessary to make provision against arcing. This maybe readily accomplished by locating the poles a sufficient distance apart; but on account of the distance required between poles difficulty has been experienced in practice in constructing a switch without making it bulky and cumbersome.

My invention therefore consists in locating the contacts of the switch upon opposite sides of an insulating-plate of suitable shape and thickness. By this means the contacts upon one side may be separated a sufficient distance to prevent arcing between them, and the interposition of a suitable insulatingplate prevents arcing between contacts or terminals upon opposite sides of the plate.

In the accompanying drawings, Figure I is a perspective view of my switch complete. Fig. II is a top plan View of the same with the cap and button removed. Fig. III is a bottom plan View of the insulating-plate removed from the base, showing the knives in the position they occupy when the whole is assembled. Fig. IV is a side elevation of the subject-matter of Fig. II. Fig. Vis a section on the line V V of Fig. III. Fig. VI is a perspective View of one of the intermediate contacts detached.

Referring to the numerals on the drawings, 1 indicates a base of suitable insulating material, and 2 a protective cap or covering fitted over the flange 3 (see Fig. IV) of the base.

4 indicates an insulating-plate secured to but separated from the base. The means employed for securing the plate 4: to the base consist in the form of embodiment illustrated of the intermediate contact-studs 5, which are suitablyconstructed for the purpose. One of the intermediate studs 5 is shown in Fig. VI, in which 7indicates a tube of conductive materialas, for example, brass-provided with an intermediate flange 8, that is secured to the base 1, as by aid of screws 9. The tube 7 carries spring contact-plates 10, suitably spaced, as by washers 11. The plate 1 is secured to the tubes 7, as by screws 12, threaded into the end of the tube and having thei r heads countersunk in the plate 4..

In practice the heads of the screws 12 are covered with wax or other suitable insulating material.

The ends of the tube 7 opposite that which carries the contact-plates extend through the base, and each is provided wit-h a transverse binding-screw 14: for wiring purposes.

The contact-studs 6 are similar to the contact-studs 5, consisting of a tube 15, provided with a flange 16, that is secured to the plate 1, as by screws 17. The tube 15 carries spring contact-plates 18, suitably spaced, as by washers 19. Each of the con tact-studs 6, however, has the tube 15 only on one side of the flange 16, the bore thereof registering with an aperture in the plate a, which communicates with an insulating spacing-tube 21, communicating with an aperturein the base 1. By this means wires may be connected with the studs 6 from the back of the plate 1, each tube 15 being provided with a binding-screw 22 for securing a wire in place.

Centrally mounted upon the base 1 and within an aperture in the plate I, which is illustrated as an annular plate, is revolubly mounted an insulating-hub 24, to the opposite ends of which are secured switch-knives 25 and 26, that work between the contactplates 10 and 18, respectively, each knife being adapted to establish communication between any two of the contacts with which it is adapted to engage. The knives 25 and 20, being secured to the hub 24, bear a fixed relation one to the other and in the illustrated form of embodiment of my invention operate together, being adapted to be manipulated, as by a button 27, on the outside of the cap 2, detachably connected, as by a screw-stud 2t to the hub 2-1.. That fcaturcof the device illustrated, however, as well as the special mechanism for actuating the knives, constitutes no part of my invention and is neither illustrated nor described in detail.

The form of knife-actuating mechanism illustrated is substantially the same as that commercially known as a Hart switch. It being well and familiarly known to all skilled in the art and constituting no part of myinvention does not appear to require detail de scription or illustration. Suffice it to say in this connection that the movement of the button 27 is adapted to impart to the knives a quick abrupt movement from one set of contacts to the next set in the order of movement.

My invention, as was previously specified in general terms, consists in the employment of the members (which, for convenience of description, I shall in the claims denominate contact-making members) represented by the knives 25 and 26, that engage contacts upon opposite sides of an insulating-plate, the contacts on one side being represented by the members 5 and those upon the opposite side by the members (5.

In embodying my invention in practical form the contacts (3, for example, being of any required number, are located at such dis-- tance one from the other as will insure against arcing.

able by calculation of the forces employed. The contacts 5 are located upon the opposite sides of the insulating-plate 4, preferably at points midway between adjacent contacts 6. Security from arcing between the contacts 5 is therefore provided in the distance which Such distance-is readily determin- I subscribed my name.

which separate one contact 5, for example,

from its next neighboring contact (5.

What I claim is- 1. In an electric switch, the combination with an insulating-plate and a plurality of contacts arranged in series upon one side of said plate, and separated, respectively, by such distances as will insure against arcing, a plurality of contacts similarly separated upon the opposite side of said plate, the individual contacts of the opposite sides being separated by approximately half the distance which separates the individuals of each series as well as by the insulating-plate, of a plurality of contact-making members cooperating, respectively, with said contacts, substantially as set forth.

2. In an electric switch, the combination with an insulating-l')ase,insulating-plates and tubular intermediate contact-studs uniting the base and plate, of tubular outer contactstuds communicating through insulating spacing-tubes with apertures in the base, a

hub pivotally mounted in the base, and contact-1naking members upon the hub working upon opposite sides of the plate, as and 'for the purpose specified.

In testimony of all which I have hereunto JOHN L. CREVELING.

Witnesses:

ELMER E. ALLBEE, Row. C. SOFIO.

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