US1572878A - Switch box - Google Patents

Description

Feb. 16 1926.

H. G. BAXTER SWITCH BOX Filed March 11, 1919 2 Sheets-Sheet l INVENTOR Ham/0 6. Baxfer WITNESSES:

) AMW ORNEY' Feb. 16 1926. 1,572,878

H. G. BAXTER SWITCH BOX Filed March 11, 1919 2 Sheets-Sheet 2 52 flarg i war v BY Patent ed Feb. 16, 1926.

UNITED STATES "PATENT OFFICE.

IHLAIBOILID G. BAXTER, OF BALDWIN, NEW YORK, ASSIGNOR T WESTINGHOUSE ELEC- TRIO & MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

SWITOH BOX.

Application filed March. 11, 1919. Serial No. 281,912.-

To all whom it may concern:

Be it known that I, HAROLD Gr. Baxrnn, a subject of the King of England, and a resident of Baldwin, in the county of Nassau and State of New York, have invented a new and useful Improvement in Switch Boxes, of which the following is a specification.

My invention relates to switch boxes and particularly to safety-first switch boxes.

One object of my invention is to provide a switch box having a rotatable snap switch therein that shall be adapted to be actuated by a reciprocating lever arm.

Another object of my invention is to provide a switch box having a latch for the door thereof that shall be so interlocked with the switch that the latch and, consequently,

the door cannot be opened when the switch is closed and the switch cannot be closed when the door is open.

A further object of my invention is to provide a safety-first switch box, of the above indicated character, that shall be simple and inexpensive to construct and efective in its operation.

In practicing my invention, 11 provide a spring-actuated rotatable snap switch that 1s disposed in a box or casing having a door to the fuse compartment thereof. The switch is provided with an oscillating lever arm external to the box for actuating the same, and the door is provided with a latch for holding the same in its closed position. A cam member is associated with the switch and is so interlocked with the latch that the latter cannot be operated to permit opening the door so long as the switch is in its closed position and the switch cannot be thrown to its closed position when the door is open.

Figure 1 of the accompanying drawings is a front elevational View, with parts broken away, of a switch box embodying my invention, and Fig. 2 is a side view, artially in section and partially in elevation, of the switch box shown in Fig. 1. Fig. 3 is a side elevation of the mechanism shown in Fig. 2 showing the switch and associated parts in 0 en position.

A switc box 1 is constructed of metal or other fireproof material and is provided with a door 2 to the portion thereof adjacent fuses 3 located therein. An insulat-. ing panel board 4 is disposed in the box 1 and is adapted to support stationary contact members 5 and 6 and fuse terminals 7 and 8. The panel board 4 is also adapted to support standards 9 and 10 upon which is mounted the rotatable member 11 of the switch. A handle 12 extends from one side of the box for the purpose of actuating the switch.

Bridging contact members 13 are mounted on the member 11 and are adapted to engage the stationary contact members 5 and 6. A. cam member 14 is also mounted on the member 11 and a rod 15, which rotates with the handle 12, is disposed therein and is relatively movable with respect thereto. A lever arm 16 is mounted on, and turns with, the rod 15 and is provided with aprojection 17 that is adapted to actuate two latch members 18 and 19 when the handle approaches'its extreme closed and open positions, respectively. The latch members 18 and 19 are connected by a spring 23 which holds the said members in engagement with the periphery of the cam 14. A spring 20 isdisposed around a portion of the rod 15 and is connected, at one of its ends, to the member 11 through the cam member 14:, and, at its other end, to the lever arm 16.

The operating lever 12 is connected, through a sleeve 21, to the rod 15. The cam member 14 is provided with cut-away portions 22 and 22' which form'contact faces 22 and 22 and 22 and 22 respectively, the faces 22 and 22 serving to limit rotary movement of the cam 14- by reason of their alternate engagement with the stationary stop member 22 which is supported by the base 4. The contact faces 22 and 22 are adapted to respectively engage the latch faces 18 and 19 which are 14, to which it is attracted, ten ing to rotate the cam in a similar direction. Rotary movement of the cam is revented by reason of the engagement of the contact face 22 with the latch face 19 until after the projection 17 has engaged the extension 33 carried'by the latch'member 19 and has so moved the latch member that the latch face 19 no longer interferes with the rotary movement of the cam. At such time the cam rotates counter-clockwise through 90 with a snap, due to the tension of the .spring, and is stopped by reason of the engagement of the contact face 22 with the stop member 22. The contact face 22 will then occupy a position behind the latch face 18, as indicated in Fig. 3, and prevents clockwise movement of the cam 14 and bridging switch 6 to open position until after the lever 16 has been moved counter-clockwise a sufiicient distance to move the latch mem ber 18 clear ofthe contact face 22. The cam 14 will then rotate in a clockwise direction until the contact face 22 v engages the stop member 22*, in which position the bridging switch 6 will be held in open position. With this arrangement of elements it will be seen that an oscillatory movement of the operating handle 12 will cause similar movement of the bridging switch, and that the switch is moved to open and to closed positions with a snap.

A cam member 24 is disposed on the rod 15 and has two grooves 31 therein. The grooves 31 are concentric with the hinge of the door 2 when the cam member 14 is in predetermined open positions. A latch member 25 is carried by the door and is so actuated by a spring 26 that it normally latches the door 2 n its closed position. The latch is provided with a rojection 27 and an operating knob 28. The operating knob 28 extends through a slot 29 in the door 2 to permit the latch 25 to be moved to such posi tion as to permit the door 2 to be opened when the switchis in its open position only.

The latch 25 has a projection 30 thereonthat registers with the grooves 31 of the cam member 24, under predetermined conditions, to permit relative movement of the door and the switch. That is, the projection 30 is movable in the grooves 31 to ernit opening of the door only when the switch is in its'o en position and it so engages the grooves t at the switch cannot be thrown to its closed position until the door is fully closed. A stop 35 is provided for retaining the pro'ection 30 in the groove 31 so long as the door is open. The projection 27 of the latch 25 is adapted to engage the portion 34 of the cam member 24 to prevent the operation of the latch and thus the opening of the door when the switch is in the closed position, as shown in the drawings. However, when the switch is in its open position, the cam member 24 will assume such position as to permit the projection 27 to move to such position that the latch is in its open position and the door may be opened, thus permitting the portion 30 of the latch to assume the position shown in the broken lines in Fig. 2 of the drawings.

When it is desired to operate the switch, the lever arm 12 is moved to such position that the projection 17 on the lever arm 16 locking means between the switch and the latch member of the door, may be actuated by an oscillating handle.

My invention is not limited to the particu lar structures illustrated, as it may be variously modified without departing from the spirit and scope of the invention, as set forth in the appended claims. 1

I claim as my invention: 1

1. The combination with a casing having an opening therein and a door for the opening, of a rotatable switch, a shaft therefor, an oscillating handle for actuating the switch, a latch for the door movable with respect thereto, and a cam member mounted on the shaft and inoperable by the latch for so cooperating with the latch and the switch that the door is prevented from being opened when the switch is closed and the switch is prevented from being closed when the door is open.

2. The combination with a casing having an opening therein and a door for the opening, movable to open and to closed position,

of a rotatable switch mounted on the casing and o erable from without the' casing, a

shaft or the switch, a cam mounted on the shaft and movable with the switch, a latch for the door movable with respect thereto, and movable therewith and so interlocked with the cam that operation of the switch is prevented by the latch so long as the door occupies a position intermediate closed position and open position;

3. The combination with a housin having an opening therein and a door for t e opening, of a rotatable switch, a latch for the door carried by the door and having an extension swinging inwardl into the hous ing when the door is move to open osition and a cam member within the housmg and inofigrable by the latch for so co-o eratin wit the latch and the switch that t e latc 1s prevented from being moved to release the door when the switch is. closed and the switch is prevented from being closed when the door is open.

4. Switch mechanism comprising a casing having fan opening therein, a, hinged door for the opening, a rotatable switch within the casing, an interlocking member having a convex surface concentric to the axis of the switch and a concave surface concentric to the axis of the door hinge, and a latch member movably mounted upon the door and having one portion engaging the convex surface, when the switch is in closed position, for preventing opening movement of the latch and another portion for engaging the concave surface, when the door is open, for preventing closing movement of the switch.

5. The combination with a housing having an opening therein and a door for the opening, a rotatable switch within the housing, a rotatable cam within the housing and movable with the switch, and a latch carried b the door and movable with respect thereto for swinging into the housing when the door is opened into interlocking engagement with the cam, the said cam and latch being so arranged as to prevent operation of the cam by the latch and to prevent opening movement of the cover when the switch is closed and closing movement of the switch when the cover is open.

In testimony whereof, I have hereunto subscribed my name this twenty-eighth day of February, 1919.

HAROLD G. BAXTER.

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