US671763A - Junction-box. - Google Patents

Description

Nu. 67!,763. Patented Apr. 9, IBM. E. T. GBEENFlELD.

JUNCTION BOX.

(Applicaltion filed Mar. 2; 1901-) (No Model.)

E392 v Z #47 @513 M w t J6 647/660 M UNITED STATES PATENT @FFICE.

EDWIN T. GREENFIELD, OF NEW YORK, N. Y.

JUNCTION-BOX.

SPECIFICATION forming part of Letters Patent No. 671,763, dated April 9, 1901. Application filed March 2, 1901. Serial No. 49,565. (No modelvf 7 To aZZ whom it may concern.-

Be itknown that I, EDWIN T. GBEENFIELD, tion, such as will enable others skilled in the 55 acitizeu of the United States, residing at New art to construct and use the same, 13 B rep- York, in the borough of Manhattan, county resent a junction-box made, preferably, in

and State of New York, have madea new and two parts, as illustrated in 1, and prouseful Invention in Junction-Boxes, of which vided with semicircular openings for the inthe following is a specification. lets, the arrangementbeing such that when 60 My invention has for its objects, first, to the two parts are secured together they conprovidea junction-box with metallic bushings stitute a complete two-partju nction-box, genfor uniting the box to the ends of adjacent erally like that disclosed in my Patent No.

conduit pipes or tubes and in such manner 665,676, granted January 8, 1901. that little or no abrading or damaging efiect My improvement consists in providinga tu- 65 will be offered to the insulation of the wires bularmetal bushing B'Zfiared orbell-mouthed or conductors when drawn therein, and, secat its inner end and having a shoulder S,

15 0nd, to provide a junction-box with metallic adapted to bear against the inner surface of bushings for uniting the box to the ends of the junction-box when put in place, so that adjacent conduit pipes or tubes and in such the outer portion thereof constitutes a neck 70 manner that the constructor will not be refor sustaining the adjoining end of a conduit quired to screw-thread the ends of the pipes pipe or tube P, the exterior inner surface of or tubes when wiring a building. the bushing being of greater bore, as shown Existing rules of the National Board of Fire at A, said bore being such that when the con- Under-writers in the United States require duit pipe or tube P is put in place the con- 75 that in the wiring of buildings in which the tinuous inner surface ofiers no roughened or wires are protected by interior or house conabrading surface.

duits and metallic junction-boxes there shall 3 represents a set-screw for securing the be offered no abrading or tearing surfaces to bushing and the end of the conduit pipe or the insulating-surfaces of conductors when tube together, thereby avoiding the necessity 8o drawn therethrough when placing the same of screw-threading the inner ends of the conin position. For the purpose of complying duit pipe or tube P and the corresponding 0 with these rules it has heretofore been cusinner surface of the bushing.

tomary to insert bushings or sleeves in-the In Fig. 2 I have illustrated a modified form necks or inlets of junction-boxes, the inner of the invention, in which the entire interior 85 ends of which bushings are flared or of belldiameter of'the bushing 13 is the same as that mouth shape, said bushings being usually seof the conduit pipe or tube P, 0 being a metal 5 cured in place by screw-threads in the inlets collar adapted to be slipped over the adjoinof the junction-boxes or else provided with ing ends of the bushing and the conduit pipe screw-threads at their exterior ends to which or tube, and s s set-screws for firmly securing go the conduit pipes or tubes are attached by corall of the parts together. responding screw-threads. My invention is In Fig. 3 I have illustrated a still further 40 designed to accomplish these results, in so far modified form of the invention, in which the as possible, without the use of screw-threads bushing B is screw-threaded at its inner end or at least to avoid, in so far as possible, the and is provided with a nut N, adapted to be 5 necessity of screw-threading the ends of the secured in place after the screw-threaded end conduit pipes or tubes at the time a building of the bushing is inserted in the opening in is being wired, thereby materially saving in the junction-box, the other parts of the bushexpense and labor. ing and the set-screw s for uniting the con- Referring now to the drawings,Figure 1 repduit pipe or tube P thereto being substantially 10o resents a part-sectional and part .side elevalike those disclosed in Fig. 1. tional view of. a junction-box embodying my I do not limit my invention to the details of improvement. Figs. 2 and 3 are sectional construction hereinbefore described, as I heviews illustrating modified forms of the inlieve I am broadly entitled to claim a bushing vention. forjoininga junction-box with a conduit pipe :05

Referring now to the drawings in detail for or tube in which the interior diameter of the a full and clear understanding of the invenbushing and conduit pipe when joined together constitutes one continuous surface,the bushing and the cond uit-pipe beingjoined together by set-screws, substantially as shown to this feature.

Having thus described my invention, what I claim, and desire to secure by Letters Patent of the United States, is to 1. A flared or bell-mouthed bushing for a junction-box provided with an interior shoulder for securing it within the junction-box; in combination with means for uniting a conduit pipe or tube and the bushing together I5 by pressure, substantiallyasdescribed.

2. A flared or bell-mouthed bushing for a junction-box, the outer interior diameter of which is greater than the diameter of the bushing proper; in combination with a con- 5 and described, and my claims are generic as ;duit pipe or tube and oneor more set-screws for securing the same together, substantially as described.

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

EDWIN T. GREENFIELD.

Witnesses O. J. KINTNER, M. F. KEATING.

Images