US1938721A - Switch - Google Patents

Description

M. H. RHODES Dec. 12, 1933.

SWITCH Filed April 9, 1932' HIE Patented Dec. 12, 1933 PATENT OFFICE UNITED STATES.

SWITCH Marcus H. Rhodes, Hartford, Comm, assignor to M. H. Rhodes, Inc., Hartford, Conn., a corporation of Delaware This invention relates to switches, and with regard to certain more specific features to electric circuit making and breaking switches.

Among the several objects of the invention may be noted the provision of an electrical switch of the class described which is quick and positive in its action, and which is capable of carrying a relatively high current; a switch of the class described including terminal pieces constructed to minimize arcing and the like; and a switch of the class described wherein a series of parts are formed of contacting metal which is enabled by other parts to carry a current considerably larger than ordinary without occasioning deleterious arcing and the like. Other objects will be in part obvious and in part hereinafter explained.

The invention accordingly comprises the elements and combinations of elements, features of construction, and arrangements of parts which will be exemplified in the structures hereinafter described, and the scope of the application of whichwill be indicated in the following claims.

In the accompanying drawing, in which is illustrated one of various possible embodiments of the invention,

Fig. 1 is a vertical cross-section of a switch embodying the present invention;

Fig. 2 is a vertical cross-section taken on line 22 of Fig. 1; and,

Fig. 3 is a horizontal cross-section taken along line 3--3 of Fig. 1.

Similar reference characters indicate corresponding parts throughout the several views of the drawing.

The present invention is concerned, in a general way, with switches of the type disclosed in my copending application, Serial Number 509,333, filed January 17, 1931. The present invention is in the nature of an improvement over the switch shown in said prior application. Particularly, the present switch is designed for carrying current considerably in excess of that safely carried by said prior switch, without appreciably increasing the size of the switch or considerably changing the majority of the parts.

The present switch, as illustrated in Fig. 1, comprises a control handle 5 which manipulates the over-centering device indicated generally by numeral 6. The end of the over-centering device 6 is in a lost-motion engagement with an anvil piece 93, which is carried rotatably upon a pin 89. Also rotatably mounted on the pin 89, but non-rotatable with respect to the anvil piece 93, is a contactor bar 95. The contactor bar 95 engages, or disengages as the case may be, terminal pieces 15 and 1'7 at its left and right hand sides respectively, as actuated by the overcentering device and the control handle.

The over-centering device of the present invention is not substantially different from that of said prior application, and will accordingly be described only in general terms. It comprises a swingable hammer saddle which is pivoted about the same pin 29 on which the control han- 65 dle 5 rotates. Mounted on the control handle 5 is a saddle member 43 which has a nose 49 extending therefrom. The saddle 43 is nonrotatable with respect to the handle 5. Supported between the nose 49 and a nose 71 on the hammer saddle 65 s a compression spring 51. Movement limiting means 5'7 restricts the degree of rotation of the control handle 5. a

It will be seen that as the control handle 5 is moved from one position to another,'the rela- 75 tive position of the noses 49 and '71 change, with the result that the compression spring 51 is at first compressed against the nose '71 and then, as the central position is passed, it expands and forces the hammer saddle 65 in the 30 oposite direction with a snap-action. The same action occurs on reverse manipulation.

The contactor assembly comprises the anvil piece 93, which is preferably made of fiber or other insulating material, and which has a notch 99 therein for accommodating the actuating end of the hammer saddle. The anvil piece 93 is mounted upon a pin 89, which is supported on one end by a side wall of the switch housing 13, and on the other end by a lug 87 formed 90 in the bottom of said switch housing 13.

Likewise mounted on the pin 89, but nonrotatable with respect to the anvil piece 93, is. a contactor bar 95. The contactor bar com prises angularly arranged arms 97, each of which 95 in turn comprises a pair of parallel spring metal or other contacting material strips 98 and 101 (Fig. 2). Ordinarily, the contactor bars 98 and 101, by reason of their resilience, rest against "1 102, which are struck to be positioned alternately on either side of the plane of the arm 84 (see Fig. 2). The tabs 102 provide means for securing a fiber or like insulation extension piece 103 to the strip 75. The piece 103 is preferably of substantially the same thickness as the metal strip '75, and is positively secured thereto by means of rivets 105 passing through the tabs 101. The contour of the fiber piece 103 is such as to extend the blade 83, and fill in the space between the arms 83 and 84. The front edge 107 of the piece 103 is an extension of the front edge of the blade 83 and is arcuate about a center represented by the pin 89.

The contacting strip 77 associated with the other terminal 17 is similarly provided with an extension or fiber piece 109. Tabs 111 similar to the tabs 101 secure the piece 109 to the strip 77. I The front edge 113 of the piece 109 is likewise arcuate with respect to the center represented by the pin 89.

As the switch is assembled, the arms 99 and 101 of the contactor bar 95, resiliently embrace or surround either the strip 75 and fiber piece pieces and '77 respectively, and on to the fiber pieces 103 and 109 respectively. In this operation, the fiber pieces 103 and 109 act in the capacity of spark or are, breakers, or preventers. Further the fiber pieces 103 represent transverse barriers which prevent the circulation of air,.

and thereby additionally inhibit the formation of sparks and arcs from that cause.

It will be seen that the fundamental principle upon which the present invention is based is that upon a separation of the conducting pieces to break a circuit, insulation material is immediately interposed between them, instead of an air gap. This interposed insulation inhibits arc formation to such a degree that currents considerably higher than those normally used with the weight or thickness of metal comprising the contactor bar and terminal strips '75 and 77, may be used. For instance, without changing the relative metal gauge of the conducting parts, switches ordinarily safely accommodating the order of three amperes are, by the addition of the insulating pieces, enabled to carry current safely up to the order of twenty to thirty amperes. Thus, with a switch of the size previously considered adapted only to carry small current, it is possible with the present invention to carry currents of medium or high value.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As many changes could be made in carrying out the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

I claim:

1. An electrical switch comprising a pair of terminals and a rotatable contactor bar adapted to connect and disconnect said terminals, and means rotating said contactor bar with a snap action upon manual actuation thereof, said terminals being of relatively fiat, thin metal, each terminal supporting a fin of insulating material thereon, said fins extending from the terminals in the direction taken by the rotatable contactor bar in its disconnecting movement, said fins being substantially the same thickness as said terminals and forming, in effect, a continuation of the said terminals, with no space therebetween, said contactor bar comprising a pair of spring metal blades for each terminal, said blades being positioned one on each side of its respective terminal.

2. An electrical switch comprising a pair of terminals and a contactor bar adapted to connect and disconnect said terminals, each terminal sup- MARCUS H. RHODES.

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