US1153257A - Switch. - Google Patents

Description

- UNITED sTATEs' PATENT oFFToE.

LOUIS REINHARD, 0F MILWAUKEE, WISCONSIN, ASSIGNOR TO THE MECHANICAL APPLIANCE COMPANY, OF MILWAUKEE, WISCONSIN, A CORPORATION 0F WIS- CONSIN.

SWITCH.

Patented sept. 14', 1915.

Applies/cion led February 28, 1914. Serial No. 821,771.

accompanying drawing, forming a part of this specification.

My invention relates to improvements in switches, and particularly to switches operated by centrifugal force.` l

One of the objects of my invention 1s to provide a centrifugally operated switch which shall have a snap movement andg one in which the movable members shall move to closed position with a quick snap action' thereby preventing arcing at the contact points.

'For the purpose of disclosing my invention I have illustrated the same in connection with a switch operated to short-circuit .the windings of an alternating current motor after the rotor thereof has reached a predetermined speed.

In the drawing disclosing one embodi' ment of my invention, Figure 1 is a front elevation of a switch embodying my invention, the cover of the :casing inclosing the switch being'removed; and Fig. 2 is a sectional View taken on the line 2 2 of Fig. 1.

In the embodiment illustrated I have shown a switch for short-circuiting the windings of the rotor of an alternating current. The switch illustrated comprises a casing 1 which is secured by any suitable means to the shaft 2 of the rotor of the alternatingV current motor 3. This casing has mounted therein a plurality of switch contacts which comprise spring lingers 41 mounted upon posts 5. These posts are secured in the back of the casing and are insulated from the casing by suitable insulating bushings 6, and the posts, at their rear ends, carry binding screws 7 to which the windings of the rotor may be connected. In the switch illustrated I have shown live of these posts which carry spring fingers. An arm 8 is pivotally mounted upon a stud 9 by means of a screw 10 within the casing and is provided at its outer end with a weight 11. Integrally formed with the arm is an arc shaped member provided with 'a plurality of radial projections or contacts 12 adapted to make Contact with vthe spring fingers 4 of the dif-l ferent posts. The arm andare shaped member form a ring provided with contacts by which the. various posts will be short-circulted on one another. The contact members 12 are held out of contact position by means of a coiled spring 13 which is, mounted upon a post l-'L The upper end ofthis lpost pro- ]ects through an opening in the arm 8 and the lower end of the post is provided with a head 15 against which one end of the coiled sprlng abuts. This head bears upoh the end of a pointed. screw 16 mounted in the casing, which screw is held in its adjusted poi sition by means of a. lock nut 17.

The operation of the device so far described is as follows: When the motor reaches a predetermined speed the centrifu-l i gal force induced by the rotation of the switch will cause the arm to move on-its pivot against the action of the spring 13 and move the contacts toward a closed position, e

or to a. position to cause the projections 12 to engage the sprmg fingers 4 on the various posts. I have discovered, however, that this movement is more or less slow, and, as a re` sult, the contacts are burned out due to the arcingl between the same when they are moved slowly into engagement with euch other. In order to prevent this movement and in order' to provide a snap action, I provide a snap spring 18 mountedon a post y19 secured in the casing and provided, at its` outer end, with a semi-spherical trigger 20..

This trigger is adapted to fit in a rounded recess formed in the arc shaped portion, which recess, however, is of such depth that the ball-shaped trigger will not pass below its center point. This trigger is adapted to engage in its recess whenv the contacts are in their open position and when v. the speed of the switch has reached a pre-'f determined point; the centrifugal force causing the arm to tend to rotate in its pivot 9 will cause the trigger 20 to ride out of its recess, thereby releasing the contacts and permitting them to quickly snap over to closed position.

It will be noted that due to the construction of this switch no matter in which. direction it is rotated the centrifugal force will act equally well to cause it to close.

While I have shown and described one form of my invention it will be understood that changes may be made in the embodlment thereof:` without departing from the spirit of the invention as set forth in the appended claims.

f Having thus described my invention what I claim as new and desire to secure by Let- .4 ,ters Patent is l. In a switch, the combination -with a 'ro- Atatablemember, of a plurality of contacts carriedthereby, an arm pivotally mounted lon said rotatable member and carrying an member and carrying an annular contact carrying member moved by centrifugal force to place the contacts carried thereby into engagement with said relatively stationary contacts, and'nieans for holding said armagainst movement until said rotatable member has reached a predetermined speed.

. 3. In a switch, the combination With a rotatable member, of a plurality of contacts carried thereby and circumferentially spaced, an arm pivotally mounted on said rotatable member and carrying an annular member having a plurality of radial contact arms, said annular member being moved by centrifugal force to place said radial arms in contact with said relatively stationary contacts, and means for holding said arm against movement until said rotatable member has reached a predetermined speed.

4. In a switch, the'combination with a r0- tatable member, of a plurality of contacts carried thereby, an arm pivotally mounted on said rotatable member and carrying an annular contact carrying member moved by centrifugal force to place the contacts carried thereby into engagement with said relatively stationary contacts, and a trigger comprisinga semi-cylindrical spring mounted member engaging a semi-cylindrical recess for holding said contact carrying member againstmovement until the centrifugal force reaches a predetermined point.

In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

LOUIS REINHARD. Witnesses:

R. G. KELLOGG,

E. EvENsoN.

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