Title:
Enclosed and protected electrical apparatus
United States Patent 2362148


Abstract:
The present invention relates to enclosed and protected electrical apparatus. The need for enclosed and protected electrical apparatus arises where the apparatus is subject to hazardous surroundings or conditions caused by the presence of corrosive or explosive vapors, steam, water or other...



Inventors:
Naysmith, Shirley R.
Application Number:
US45235242A
Publication Date:
11/07/1944
Filing Date:
07/25/1942
Assignee:
MILLER CO
Primary Class:
Other Classes:
174/656, 362/220
International Classes:
F21V21/30; F21V25/12
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Description:

The present invention relates to enclosed and protected electrical apparatus.

The need for enclosed and protected electrical apparatus arises where the apparatus is subject to hazardous surroundings or conditions caused by the presence of corrosive or explosive vapors, steam, water or other liquids. The entire apparatus in the region presenting the hazard must be proof against damage and ordinary constructions based on mere mechanical strength and electrical safety do not suffice. Resort has to be made to heavy, sturdy and more expensive arrangements which can be assembled and installed in place. In certain fields, such as in lighting, heat ray projection, and the like it is necessary to be able to adjust the relative position of the parts, and the invention is herein shown in connection with vaporproof fluorescent lighting fixtures wherein means is provided for adjusting the lighting fixture about a horizontal axis, usually lengthwise.

The present invention contemplates the supporting of the vaporproof body or housing, whether of a lighting fixture or other device, from two spaced conduits, which may be pendent, or, otherwise, by suitable coupling devices which provide junction boxes to accommodate a vaporproof wire connection and at the same time permit adjustment of the said body about a horizontal longitudinal axis.

The accompanying drawing shows for purposes of illustrating the present invention, several embodiments in which the invention may take form, it being understood that the drawing is illustrative of the invention rather than limiting the same.

In the drawing: Figure 1 is a side elevational view of a lighting fixture and its supports; Figure 2 is an end elevational view of the lighting fixture showing angular adjustment of the fixture body relative to the supports; Figure 3 is an enlarged vertical sectional view on the line 3-3 of Figure 2 showing one form of construction; and Figures 4, 5, 6 and 7 are views similar to Figure 3 showing modified forms of construction.

'The fixture body 10 is rigid and carries the fluorescent lamps, auxiliaries and wiring in the usual manner. It may include a reflector I1, end walls 12 and 13 and preferably is of a vaporproof type. The closure (not shown) may be of the type shown in the application of Gillson W.

Beals, Serial No. 379,917 (now Patent No. 2,291,495 of July 28, 1942).

End walls 12 and 13 of the fixture are provided with wire receiving openings 20. Opposite each opening a trunnion member 2 I and gasket 22 are secured by screws 22'. The trunnion member has a smooth machined vertical end face 23 and an outwardly extending flange 24. This end face and flange are annular with respect to a threaded stud 25 formed on the trunnion member. This trunnion member has an arcuate slot lo 26 to form a wireway adapted to accommodate wiring.

In the form of construction shown in Figure 3 the stud 25 on the trunnion member 21 passes through a hole 27 in a fitting 28. This fitting has a smooth machined flat face 30 to engage the end face of the trunnion and form a vapor tight joint. The fitting 28 also has a semi-circular shelf 29 with a groove 31 of annular shape which extends up to the horizontal axis of the trunnion member, this groove being adapted to receive the flange 24 on the trunnion member so as to take the load. A nut 32 and lock washer 33 secure the parts together. The fitting 28 has an arcuate wireway 34a and a large wiring chamber 34b. This wiring chamber is closed by a cover 35 threaded in place against a gasket 36. The trunnion and fitting may be in the form of castings.

Where the fixture is pendent each fitting 28 has a conduit receiving boss 37 at the top for pipe 38. When the fixture is supported in other than a pendant manner the fittings would be provided for connection with the conduits at suitable desired positions. All these fittings are, of course, vaporproof.

When two of these supporting devices are employed each forms a junction box when the cover is off, and the entire fixture may be turned about the horizontal axis when the nut 32 is loosened and may then be secured in place by tightening the nut, so that the surface of the fixed and movable elements frictionally engage. The body of the fixture is securely held in the desired position. A stop screw 39 prevents twisting off the wiring, or such stop screws may be dispensed with when the size of the fixture body is such as to prevent a complete turn of the body.

In the form shown in Figure 4 the trunnion member 40 (generally the same as in Figure 3) is tapped at 41 and a combined cap and bolt forming member 42 closes off the chamber 43 of the fitting 44 and fastens the parts together so as to exclude vapors.

In the form shown in Figure 5 each trunnion member 50 (secured to a fixture body in any convenient manner to secure a vapor tight joint) has a constricted wireway 51 adapted to receive a sealing compound or pitch 51', and has a centrally tapped hole 52. The fitting 53 is held in place by a bolt 54 and cover 55, the latter forming a cover for the wiring chamber. With this form of construction the sealing is accomplished in the parts fixedly carried by the fixture body, and the wiring in the junction box is protected by the clamping action of the smooth faces of the trunnion member 50, fitting 53 and cover 55.

An annular recess 56 in the trunnion accommodates wires so that they may be pushed out of the way when the mechanical assembly is being done.

In the device shown in Figure 6 the fitting 60 is secured to the trunnion member 61 (like 50) by an external yoke 62 and screws 63 passing through flanges 64 on the yoke and fitting, respectively. The wiring chamber is closed by a cover 65.

The construction shown in Figure 7 differs from the preceding arrangements in that the trunnion member 70 has an annular groove 71 to receive a flange 72 on the semi-circular shelf 73 carried by the fitting 74.

The devices above described operate generally alike in that the fixture body is swiveled for turning about a horizontal axis and the fixture can be temporarily supported for wiring and wired, also all parts are vaporproof.

Since it is obvious that the invention may be embodied in other forms and constructions within the scope of the claims, I wish it to be understood that the particular forms shown are but a few of these forms, and various modifications and changes being possible, I do not otherwise limit myself in any way with respect thereto.

What is claimed is: 1. Means for supporting electrical apparatus having an enclosing, vaporproof body for angular adjustment about a horizontal axis extending through said body, comprising body-carried, outwardly extending members of annular configuration about said axis, fixed fittings rotatably receiving the outwardly extending members and having upwardly opening semi-cylindrical shelves, said members and shelves having cooperating grooves and flanges to interengage and prevent axial separation of the parts, and clamping devices for effecting frictional interengagement of the fixed fittings and the outwardly extending members, said fittings and outwardly extending members forming wireways for wiring to said body.

2. Means as claimed in claim 1, wherein the clamping devices include cooperative axially extending threaded elements one carried by each body-carried member and the other bearing against the fitting.

3. Means as claimed in claim 1, wherein each of the clamping devices includes a threaded stud carried by the body-carried member and passing through a hole in the fitting, and a nut threaded in the stud.

4. Means as claimed in claim 1, wherein each of the clamping devices includes a threaded hole in the body-carried member and a bolt threaded into said hole.

5. In combination, electrical apparatus having an enclosing, vaporproof body provided with outwardly extending trunnions of annular contour about a horizontal axis, two fixed trunnion supports each having an upwardly facing recess adapted to reecive the end of a trunnion from above and rotatably support the same, the trunnions and supports having cooperating grooves and flanges to interengage and prevent axial separation of the parts, and means to non-removably secure the trunnion supports to the trunnions for rotary movement about said horizontal axis, said means including means to bring about frictional engagement of relatively fixed and movable surfaces whereby said body may be clamped in adjusted positions.

6. The combination of claim 5, wherein each trunnion has a wireway leading into the body and each trunnion support has a splicing chamber provided with a removable cover.

7. The combination of claim 5, wherein each trunnion support has an outwardly extending coupling element for securement to a conduit, and the trunnions and trunnion supports have wire passageways extending from the body to the conduits.

8. In combination, electrical apparatus having an enclosing, vaporproof body provided with outwardly extending trunnions at the ends thereof each having a horizontal tapped hole, an outwardly extending concentric flange having a face toward the body, and an end face beyond the flange, a pair of fixed trunnion supports each having an upwardly facing groove to receive a trunnion flange, and a face bearing on the end face of the flange, and a bolt threaded into each of said tapped holes for clamping each trunnion against each support in various positions of adjustment of the body about a horizontal axis.

9. In combination, electrical apparatus having an enclosing, vaporproof body provided with outwardly extending trunnions at the ends thereof, each having a horizontal tapped hole, an outwardly extending concentric flange having a face toward the body, and an end face beyond the flange, two fixed annular trunnion supports, each having an upwardly facing groove to receive a trunnion flange, an inner face bearing on the end face of the flange, and an opening in its outer face, a cover for said outer face opening, a bolt passing through the cover and threaded into each tapped hole of the trunnion for clamping the cover against the support and the support against the trunnion in various positions of adjustment of the body about a horizontal axis, each cover and trunnion support providing a splicing chamber, and each trunnion having a wireway com;.5 municating therewith and with the body, 10. In combination, two substantially fixed, vaporproof wiring conduits spaced apart, each having a fitting secured to its end, the fittings having parallel vertical inner faces, semi-circular, inwardly extending, upwardly facing shelves provided with upwardly opening annular recesses each fitting having an outwardly opening splicing chamber, a vaporproof housing having outwardly extending trunnion members provided with passageways for wiring and with flanges to fit into the annular recesses whereby the housing may be supported by the fittings and the wiring between the conduits and housing be completed in the splicing chambers, and covers for the splicing chambers.

SHIRLEY R. NAYSMITH.