US614882A

US614882A - Thomas j

Info

Publication number: US614882A
Authority: US
Publication date: 1898-11-29
Anticipated expiration: 1915-11-29

Description

Patented Nov. 29, 1898. T. J. MURPHY.

JUNCTION BOX.

(Application led Apr. 22, 1895. Renewed Dec. 31, 1897.-)

(No Model.)

jizz/mfom Wg M@ we: mams PEYSRS oo, PHoramNo. wAsmscmN n c UNITED STATES PATENT OFFICE.

THOMAS J. MURPHY, OF NEIV YORK, N. Y.

JUNCTION-BOX.

SPECIFICATION forming part of Letters Patent No. 614,882, dated November 29, 1898.

Application i'iled April 22, 1895. Renewed December 31, 1897. Serial No. 665,255. (N0 modem vTo all whom it' may concern:

Be it known that I, THOMAS J. MURPHY, a citizen of the United States, residing at New York city, 'in the county and State of New York, have invented a certain new and useful Improvement in Junction-Boxes, of which the following is a specification.

I-Ieretofore j unction-boxes have been made which from their mode of construction were not secure against iire risks and which were expensive in construction.

The object of my invention is the production of a cheap and simple j unction-box which is especially adapted for use in connection with systems of electrical conduiting for interiors and which will be safe from ire risks occurring within lthe box as well as from leakages of current.

In the accompanying drawings, forming part of this specification, Figure l is a plan view of a junction-box embodying my invention with the cover removed. Fig. 2 is a cross-section thereof on the line 2 2 of Fig. l with certain of the parts removed. Fig. 3 is a longitudinal section taken on the line 3 3, Fig. 1. Fig. 4 is a detail of a nipple to which the conduits are attached. Fig. 5 is a modified form of box. Fig. 6 is a longitudinal section thereof through the line 6 6, Fig. Fig. 7 is another form of box. Fig. Sis a longitudinal section thereof on the line S S, Fig. 7. Fig. 9 shows afbox with the cover in place and without nipples, and Fig. 10 is a cross-section thereof on the line 10 lO.

A is thewooden casing of the box, which serves to receive the lining B. This lining is of a refractory non-conducting material and to its use the box owes its chief advantages. I prefer slate, as at once fulfilling the objects named and at the same time being cheap. As shown in the section Figs. 2 and 3, the bottom of the box, as well as the sides thereof, is lined with this refractory non conducting material. A cover also lined with the same material is to be used with this box,

so that the whole interior of the box is made thereof. In Figs. 5, 6, 7, 8, 9, and 10 I have shown this simple form of slate-lined box. In those figures, C represents -the seat for the door, which is formed by the top edge of the slate lining of the box.

In Figs. 1, 2, and 3 is shown what I call my double slate-lined box-that is to say, I take the box already described and within it form another box` D of the same refractory and insulating material-as, for instance, slate, as shown-by preferably providing a bed-block of slate F., surrounded by the four walls, (lettered D,) as shown in Figs. 1 and 3 particularly. This double slate-lined box is particularly advantageous for the room it affords within which to make the distribution of the conductors. The electrical bindingposts, safety-fuses, or other electrical appliances used in boxes of this nature are mounted upon the slate base E, as shown, or in any suitable manner.

In order to tit the box for use with the tubes used in electrical interior conduiting, I provide a short piece of pipe F, threaded, as shown, and pass it through the wooden frame A, which frame is countersunk on the side next the slate lining, and place a Washer G on the threaded pipe within the recess. The outer end of the short section of screwthreaded pipe receives another washer II, as shown more particularly in Fig. 4, these washers serving to keep the pipe in place. It is obvious that a threaded conduit-pipe might be secured directly to the projecting nipple or a suitable protecting-coupling used to secure the said pipe to the nipple. By this arrangement instead of passing the conduitpipe directly into the interior of the box, where it might be difficult to make the connection, the connection is made on the outside, where there is usually ample room to work. Again, by this arrangement I avoid weakening the slate lining to a great extent, fory the reason that I do not need to bore the same to the extent of the full outside diameter of the conduit-tube, for by the arrangement shown the nipple F projects against the slate lining, and it is necessary only to provide an opening in the slate lining large enough to take therethrough the conductors I, which opening of course is only about as large as the interior diameter of the nipple.

It will be observed that when a box is completely lined with slate or other refractory non-conducting material in the manner I have described there will be absolutely no danger of leakages of current therefrom, and should there be any crosses, blowing of safety-fuses,

IOO

or short-circuits within the boX any aroing resulting therefrom will be eonnecl to the interior of the box and will not set lire to surrounding inflammable materials, nor will the box be heated up by low-resistance crosses of long duration, as would a metal box Without a similar lininO.

I claim- A box for mounting and Connecting eleotrieal Conductors, comprising an exterior Wooden shell, a lining of a refractory, nonoonduoting material therefor, a cover provided with a similar lining, and a screw nipple or nipples extending through said eXterior Wooden shell against the lining, said lining being oountersun k and receiving1 a Washer, with a Washer on the outside of the Wooden shell, all substantially as set forth.

This speoication signed and witnessed this 20th day of April, 1805.

THOMAS J. MURPHY. Witnesses:

JOHN R. TAYLOR, S. O. EDMoNDs.'