US1224881A - Electric switch and fuse box. - Google Patents

Description

L. F. KRIES ELECTRIC SWITCH AND FUSE BOX.

APPLICATION FILED AUG-3011913- Patented May 1, 1917.

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. En-acme swrrcn Ann rnsE Box.

v Specification of Letters Patent.

I Patented May 1, 1917.

ori inal application illedluarch 12, 910, Serial No. 548,925. Divided and this application filed August so,

1913.- -Serial1o.787,438.

7 To aZ'Zit mqy concern Be it known that I, LAWRENCE F. KRIES, a citizen of the United States, residing at Baltimore, State-of Maryland, have invented certain new-and useful Improvements in Electric Switch and Fuse Boxes, of which 7 the following is a specification.

This aPPlIGafiOILiS a division of my application Serial Number 548,925, filed March My invention pertains to boxes or holders for electrical apparatus, and is designed to permit the opening thereof whenever necessary for inspection or. renewal of theapparatus, but to preclude the passage of the current to the apparatus while the box or holder is open, and to prevent the possible taking of current at such time from within the receptacle. Though susceptible of use in various other relations or with other apparatus, the invention is primarily intended for, and is illustrated in connection with, a switch and fusebox for the introduction of current from a service main into a room or building where the current is to be used.

Briefly stated, the invention consists in a novel construction and arrangement of parts,

. prominent among'which is a closure for the fuse box orapparatus-containing receptacle,

which closure is so connected with or related to; a line switch that the switch must be opened before, and remain open during, the

opening of the closure. The said switch, together with the line terminals, and all amciated parts which are charged, even when the switch is open, are so mounted in said receptacleas to be entirely inaccessible. Various other features, details, and combinations'will be pointed out.

The details of construction may vary widely within the limits of my invention, a convenient form of the structure, when designed as a fuse box, being represented in the accompanying drawing, in which Figure 1 is a section through a box embodying my invention on the line 1 -1 of Fig. 2; and FFig. 2'is a section on the line 2.-2 of 1g.. Referring by numerals to the structure shown in the drawings, 1 represents the easing or box that incloses the device. This may be of -..cast iron, pressed steelor any other suitable material, the principal requisites being that the box be tight and strong.

.So far as possible the use of screws and other removable fastenings is avoided which I shall call the fuse chamber and switch chamber respectively, though it will be understood that other apparatus than fuses might be inclosed therein. The partition 3 is insulated from the connections carried by the base 2, by insulating strips 6 extending beyond its edge and attached by screws 7 insulated from the switch chamber side.

Where the switch box is used to control the circuit entering a building, the connections from the street main will enter the box at 8. In such service a lead sheathed cable 9 is commonly used and a convenient mode' of attaching such cables is to provide a 0011ical nipple on the box, force the lead sheath 11 of the cable over this nipple and clamp it in place with a ring 12 held by bolts 13.

Any other suitable method may of course be employed, the idea being merely to secure a tight joint between the sheath and the box.

The conductors 14: carried by the-cable 9 enter the box and are connected to their respective line terminals 15' carried by the base 2. In the drawings a box for a threewire system is shown, but obviously the number of 'wires to be handled may be readily varied according to individual requirem'ents, .the only details affected being the number of switch blades, fuses, etc.

Theswitch terminals 15, which'are connected with the line terminals, are the ordi- I d -'10 nary contacts of a multiple knife switch and when the switch is closed as in Fig. 1,

, the, circuits are continued through the switch bladesv 16, terminals or contacts 17 to which the blades 16 are pivoted at 17,=conduetors 18, fuses 19, (mounted-in the usual terminals or clips. 20) and thence by the wires 21 inclosed by the metallic conduit 22 to the meter and house connections, The conduit 22 may be the usual metallic conduit used in interior work and be connected to the box by a nipple 23 and sleeve 24 as shown.

The switch blades 16, terminals 15 and contacts 15 and 17 are in the chamber 5 and the fuses 19 and terminals 20 are in the chamber 4 entirely isolated therefrom. Access to the chamber 5 may be had only by opening a door 25 and this door is held closed by a bar 26 passing through ears 27 on the box 1 and sealed in position by the usual lead seal. Thus access to the switch chamber is available only to authorized employees of the electric power company.

The switch, however, may be operated by anyone through the following mechanism. The switch blades 16 are connected to move in unison by an insulating bar 29 which is mounted at its ends on the arms 30' of bell crank levers 31. The levers 31 turn on pivots 32 on the box 1, the pivots 32 being alined with the pivots 17 in the switch blades 16. Access to the fuse chamber 4 can only be had through an aperture closed by a door 44 which is pivoted at 45 near its lower edge. The inwardly extending arms 52, on door 44, are connected by links 51 to the arms 33 of bell cranks 31, the links passing through narrow slots in the partition 3. Thus as the door 44 is drawn forward to gain access to the fuse chamber the'switch is automatically actuated to open the circuit, and is again automatically actuated to close the circuit upon the closing of door 44.

The parts are so proportioned that a slight initial opening movement of the door effects the complete opening of the switch. A flange 53 conforming to the path of the edge of the door and projecting from the front of, the box prevents access thereto, until the switch is fully opened.-

If for any reason desired, a glass window 54 may be placed in the door 25 to permit a clear view of the switch, as illustrated.

It is obvious that other forms of electrical apparatus in addition to or in place of the fuses shown, might be inclosed in chamber 4, the essential idea of the invention being the combination of an apparatus-com taining receptacle and a switch in such a manner that the opening of the apparatus containing receptacle becomes possible only when the switch is open. Additional features are the isolation or inaccessibility of the live switch contacts and line terminals, and various structural details above set forth. b

Obviously, various changes and modifications are possible without departing from the spirit and scope of the invention. For instance, instead of having the wires enter or leave the box at opposite ends, they may all be arranged at one end, or they may enter and leave at the sides, or in fact at any desired points, but should be led through venting access to electrical the switch and fuses in the order or arrangement here set forth. If the supply wires enter through the fuse chamber they may, of course, be protected against access therein, as otherwise current could be taken from them. The partition 3 acts as an absolute barrier to prevent theft of current from any of the conducting parts in the chamber 5.

In the following claims I use the term inaccessible in the phrases inaccessible switch or switch having inaccessible live contacts to define a structure in which the switch or live contacts are guarded from access by the ordinary user of current. The simplest means of securing such inaccessibility is to use the tight locked or sealed casing described in the specification, but the phrase is not intended to be limited to this construction.

Having thus described my invention, what I claim is 1. The combination of'a receptacle for inclosing electrical apparatus, a closure for said receptacle movably mounted thereon and controlling access to said apparatus, an electric switch for controlling the flow of current to apparatus in said receptacle and having inaccessible live contacts and line terminals, and positive connectionsbetween said switch and closure for effecting the opening and closing of said switch by the opening and closing movements of the door, and for holding the closure in closing relation to the receptacle in all circuit closing positions of the switch.

2. The combination of a receptacle for inclosing electrical apparatus, a closure for said receptacle movably mounted thereon, an electric switch for controlling the flow of current to apparatus inclosed in said receptacle and having inaccessible live contacts and line connections, and a link connecting said switch and closure and adapted to cause the same to move simultaneously.

3. The combination of a receptacle for inclosing electrical apparatus, a closure for said receptacle movably mounted relative thereto, an electric switch for controlling the flow of current to apparatus inclosed in said receptacle, and comprising fixed and movable members, a line terminal to which one of said fixed members is electrically connected, means for preventing access to such line terminal and fixed member at all times, and mechanical connections between the said movable switch member and closure for causing them to move'together in opening and closing-directions.

4. The combination of a receptacle having a closure for alternately permitting and preconnections, said closure being capable of a limited initial movement in an opening direction before permitting such access, an electric switch for controlling the flow of current to said connections and having inaccessible live contacts and line connections, and a positive mechanical connection between said door and switch for opening said switch by such initial movement of said door.

5. The combination with a box for inclosing electrical fuses, of a switch in said box, fuse terminals, and line terminals, said switch having contacts electrically connected -with said line terminals, and controlling the supply of current to said fuse terminals, a manually operable swinging door for said box, the movable part of said switch being mechanically connected with said door so *as to open and close therewith, all live parts in said receptacle, including said switch contacts and line terminals, being inaccessible in all positions of said door, and said fuse terminals being accessible only in the open position of said door.

6. The combination with a receptacle for inclosing electric fuses, of a switch in said receptacle comprising a pair of fixed contacts and a movable member arranged to bridge the same, means for connecting one of said fixed contacts to a supply wire, whereby said contact and connecting means are constantly alive, fuse terminals, the supply of current to which is controlled by said switch, and a manually operable closure for said.receptacle mechanically connected with the movable member of said switch so that said closure and member always move together, all of said live parts being so located in said receptacle as to be inaccessible in all positions of said closure, and said fuse terminals beingaccessible only in the open position of said closure.

7. The combination with a receptacle, of fuse terminals and a switch therein, said switch comprising a movable member and cooperating fixed contacts, a line terminal in said receptacle electrically connected with one of said fixed contacts, said switch controlling the flow of current between said line and fuse terminals, a manually operable closure for said receptacle mechanically connected with said movable switch member to open and close the switch when the closure is opened and closed, said closure permitting and preventing access to said fuse terminals when in its open and closed positions, respectively, and means for positively preventing access to all live conducting parts in said receptacle, including said contacts and ter minals, when said closure is opened.

8. A combined switch and fuse box having a movable closure, a switch in said box having live contacts and line connections completely inclosed-therein so as to be en tirely inaccessible at all times, fuse terminals, the sup ly of current to which is governed by sai switch, and access to which is controlled by the position of said closure relative to said box, said switch being mechanically connected with said closure so as to be both opened and closed thereby.

9. A combination switch and fuse box having a partition. dividing the same into two compartments, fuse terminals in one compartment, line terminals and a switch in the other compartment, said switch comprising fixed and movable members, and controlling the supply of current from said line terminals to said fuse terminals, a manually operable closure for said box affording access to said-fuse compartment only, and mechanically connected with the movable member of said switch to move therewith in both opening and closing directions, said switch compartment being always closed by said partition in all positions of said closure, whereby said switch members and line terminals are always inaccessible.

10. The combination with a receptacle, of fuse terminals and line terminals inclosed therein, 'a switch having fixed contacts connected with said line terminals and controlling the supply of current therefrom to said fuse terminals, a manually operable closure for said receptacle controlling access to said fuse terminals, the movable member of said switch being mechanically connected with said closure to move therewith in both opening and closing directions, and a barrier interposed between said fuse terminals and all live conducting parts, including said switch contacts and line terminals, whereby access to such parts is prevented in all positions of said closure.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

LAWRENCE F. KRIES.

Witnesses:

K. E. MoNTAoUn, PARKER DODGE.

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