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Publication numberUS1403659 A
Publication typeGrant
Publication dateJan 17, 1922
Filing dateAug 11, 1916
Priority dateAug 11, 1916
Publication numberUS 1403659 A, US 1403659A, US-A-1403659, US1403659 A, US1403659A
InventorsGeorge B Wadsworth
Original AssigneeWadsworth Electric Mfg Co
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Safety box for electric installation
US 1403659 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

G. wAnswoRTH.


Paiented Jan. 17, 1922.

i I /Oa 20 /g l Ia /0 W ga WWWW \ To 'all whom t may concer/1,:

til the switch is opened to cut off the currenty `from the fuse connections.




Specification of Letters Patent. Patented Jan. 17 1922 Application led August 11, 1916. Serial No. 114,325.

Be it known that I, GEORGE B. VADS- WORTH, a citizen of the United States, and a resident of the city of Covin t0n, in the county of Kenton and State o Kentucky, have invented certain new and useful Improvements in Safety Boxes for Electric Installation, of which the following is a full, clear, and exact description, reference being had tothe accompanying drawing, forming part of this specification.

My invention relates to switch boxes into which are led the outside mains of source of supply of electricity, in connection with which fuses are provided adapted to burn out if too heavy a current is accidentally sent through the mains.

The object of my invention is to provide a safety box for fuses and cut-out switches, whereby access to the fuses is prevented un- It is also the object to provide in such a box for means for exposing. the fuse connection for replacement of the fuse without access to the switch or other terminals, whereby it shall be impossible without permanently injuring or destroying the box to insert electrical connections to pass the current around the electric meter and thus touse current without any registration on the meter. Thus it is my object to prevent stealing of current by the consumer of electricity while at the same time giving him full access to the fuses for changing or removing them. I also`desire to provide for means for locking the switch in such boxes in open position to prevent all use of current.

Safety boxes in which the cut-out switch is arranged to prevent access'to the fuse without opening the switch have been devised, but in such devices there has heretofore been no provision made to allow for access to the fuses without also exposing the vterminals of the switch. The result of use n of such boxes is that whenever it is desired to change the fuses, the box must be opened from headquarters, which' is a great annoyance.

It is an exception to the rule that fuses must be set into the service lines or mains before the local switch, where the switch is p encased in a closedcompartment independent of the fuses. This is because there is no chance of any object falling across the termlnals o f the switch and causing a burning. Thus 1t 1 s my object to set the switch into the servlceline ahead of the fuses and enclose the s witch 1n a separated casing, thereby allowlng the fuses, when they are accessible, to be disconnected from the service line, by the opening of the switch.

These various objects I accomplish by that certain construction and arrangement of parts to be 'hereinafter more specifically pointed out and claimed.

- In the drawin v F lgure 1 is a fgront elevation of the safety box, broken away so as to reveal one of the fuses.

Figure 2 is a like view lid removed.

Figure 3 is a cross section of the box taken on the line 3, 3, of Figure 1.

Figure 4 is a longitudinal section thereof, taken on the line 4, 4, of Figure 1.

Figure 5 is a diagrammatic view of the wiring of the device.

The box, which will be considered as mounted on a wall, has the back 1, the sides 2, 2, and the base 3. The box is of stout metal, and is provided with lugs 4, 4, on

of the box with the which is seated the plate 5 of insulatin material, forming with the back of the ox a tight and complete compartment for the switch 6. The switch is mounted on the one l .side of the box on a suitable base 7, and

has the switch closer or knife 8, which is secured tightly to a revoluble post 8a that extends out through the compartment .and outside of the box.

The box has a lid 9 likewise of metal, and extending u from the lugs 4, 4, are screws 10, 10,'whicli1J pass throu h the compartment forming plate 5. On t ese screws are set sleeves or other spacer members 10a, and the screws extend up through the lid of the box. The lid is sealed down in any acceptable manner, and holds down the compartment plate by means of the spacer sleeves.

Strips 11, 11 are mounted on the under side of the lid, and are beveled to form a dovetailed guideway for a shutter. This shutter 12 has two openings 12a in it, which are adapted to register with openings 13, 13, in the lid. Thus when the shutter is in Way .one-positionjthe openings in the lid will be 14, 14, mounted in clips 15. Each fuse has a compartment formed around it by means ofvcross walls 16 and 17, whereby should a fuse-be lifted out of its socket and dropped by accident, it willnot roll to an inaccessible position. The lid, it will be remembered, is to be sealed in place, and fuses might be lost in the above manner. The revoluble post [which carries the switch knife .or closer, has mounted fixedly on it, in the space above the switch compartment andbeneath the lid of the box, an arm 18 which has a slotted'end 19. On the base of the sliding shutter is a roller or knob 20 which engages in the slot of the end 19, so that when the post is revolved to` close or open-the switch, the Shutter is moved at the same time.

On the outside of the box, thereis mounted on the post a handle 21 by which the post is revolved, and this lfandle has an indicator arrow 22 thereon.. The words Off and fOn-are printed on the lid, to indicate to the operator that when the' handle is in 'one position the switch is open, and that it is closed. -s

'W hen the switch-'is open, the parts are arranged so that the shutter is open. However, the access to the fuses through. the lid openings does not expose the switch points in any way, so that current can be stolen. Not only this, but the wiring is such that the fuses are dead when the switch is open.

As shown in the diagram,the service wires a, a, pass first to the switch, thence they pass to the fuses at b, b, andfrom the fuses the current passes by the wires c, c, to the meter d. The object being to prevent the shunting of current around the meter, it is evident that with proper conduits from the service Wires to the box, and from the fuses in another in the box to the meter, there will be no opportunity-for the fraudulent user to shunt out the meter. v i

In the above safety box there` is easy accessibility to the fuses, however, andthe only possible way of stealing current, i. e. shunting out the meter, would be to break the box, or get Wires from the fuses out through the Shutter. vTo prevent the latter of stealing, the closed spaces of theI shutter must be so proportioned that they will close up the fuse openings in the lid before the switch points make even a partial `vided with a slot or eye 23, which registers with the slot 24 in a lug 25 on the box, when the switch is open. Thus a padlock may be used to lock open the switch, which same padlock or other locking means sealed'in the usual manner.

It seems clear that any electric installation, such as to a motor, a heater or the like, wouldbe an advantageous use'for my invention, as use withl a meter to prevent stealing current is but one use. .As a safety device for cutting off current from fuses t0 prevent may be V the accidental shock to an operator in removing fuses for replacement it is very valuable. I do not wish to be limited in my claims that follow to any specific means of assembling the various elements. of my new safety box, because of a failure to mention equivalent structures in the above specification. On the contrary, I wish it understood that the above drawing and specification are descriptive of merely the preferred embodiment of my invention. v

Having thus described my invention, what I claim as new Aand desire to secure by Letters Patent, is:

1. In a switch partments, a switch in one, a fuse in the other, a lid for the box, a hole -in-the lid l' giving access to the fuse chamber, an externally operated shaft in the box having means tatable operating member for the switch,

said box having an opening for access to the fuse compartment, a shutter moving in the plane of the box about said hole, located on the inside ofthe box and adapted to block and unblock-fs'aid hole, said shutter being free of direct connection to the switch, and meansV on the operating member and the box, two separated comshutter to enforce a closed position of the shutter in all closed positions of the switch.


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US7670287 *Feb 9, 2006Mar 2, 2010Welch Allyn, Inc.Medical diagnostic instrument
U.S. Classification200/50.18
International ClassificationH01H9/10
Cooperative ClassificationH01H9/104
European ClassificationH01H9/10C