US2051479A

US2051479A - Explosion resisting lighting fixture

Info

Publication number: US2051479A
Application number: US707293A
Authority: US
Inventors: Harold P Hastings
Original assignee: Crouse Hinds Co
Current assignee: Crouse Hinds Co
Priority date: 1934-01-19
Filing date: 1934-01-19
Publication date: 1936-08-18
Anticipated expiration: 1953-08-18

Description

Aug. 18, 1936. H. P, HAsTlNGs 2,051,479

EXPLOSION RESISTING LIGHTING FIXTURE n Filed Jan. 19, 1934 2 Sheets-Sheet 1 Afr l /ll kmv INVENTOR.

ATTORNEYS,

Aug. 18, 1936.

Filed Jan. 19, 1954 2 Sheets-Sheet 2 INVENTOR.

Mu/ @7/ j BY ATTORNEYS,

Patented Aug. 18, 1936 UNITEDA STATES EXPLOSION RESISTING LIGHTING FIXTURE Harold P. Hastings, Syracuse, N. Y., assgnor to Crouse-Hinds Company, Syracuse, N. Y., a corporation of New York Application January 19, 1934, Serial No. 707,293

9 Claims.

This invention relates to lighting units of the explosion resisting type, particularly intended for use in hazardous places, where there'is the probability of explosion, if the electrical circuit is made or broken inthe atmosphere of the location.

y The' invention hasforan object an explosion resisting lighting unit provided with flame tight joints, the construction being of such nature that the efficiency of these joints will not be impaired through ordinary use of the lighting unit.

The invention has for a further object the provision of means for detachably supporting the lamp receptacle in the body` of the unit in such manner that the lamp compartment yof the unit is effectively sealed.

The invention has for a further object the provision of meansfor maintaining an effective iiame tight joint between the glass globe and the body of the unit and at the same time permitting relamping of the unit without the necessity of skilled labor or any particular tools. I A further and important object of this invention is the provision of means for securing the globe to the globe support in iiame tight relationship thereto, and also to provide for expansion and contraction of the globe without eiecting the joint.

With the above objects in mind, the invention possesses further novelty in that its structure is such that the unit can be made in the smaller sizes and can be used as an explosion resisting hand lamp, if desired.

Further objects will appear as the description proceeds.

The invention consists in the novel features and in the combinations and constructions hereinafter set forthand claimed.

InV describing this invention, reference is had to the accompanying drawings vin which like chare acters-designate corresponding partsl in all the views. Y

Figure 1 is a sectional view of the unit, partly in elevation, the unit in this instance being provided with a handle for handlamp use.

Figure 2 is a sectional view of the unit provided with means for attaching the same to an electric conduit system.

The invention comprises generally a body, a lamp receptacle support detachably secured in the body in such manner as tov provide a ame tight joint between the support and the body, a globe support detachably secured to the body and means carried by the globe support for detachably securing the globe in the support in name tight relationship `thereto and a 4guard separately secured to the support. p

As here shown, the body comprises a casting I0 bell shaped in general form and being provided with an internally threaded bore I I.` The mouth v5 or open end of theV body Illis threaded'externally at I2. I3 designates the receptacle support` and is, as here shown, provided with a depending ange I4 and an upwardly extending annular flange I5, the flange III being threaded externally l0 and the threads being complemental to those of the bore I I of the body, whereby the support may be threaded into the body.

A receptacle I6 is secured to the support I3 in any suitable manner, as by screws I 1, the support I3 being provided with passages 'I 8 to permit the service wires to be connected to the socket or lamp receptacle IS. v The upwardly extending ange I5 provides a well which islled with'suitable sealing compound, after the receptacle I6 20 has been properly wired. The externallythreaded flange I4 provides a ame tight joint between the support I3 andthe body I Il and'in conjunction with the sealing compound withinV the ange I5 forms an effective seal between the lamp compartment of the unit and the upper compartment through which the service wires enter the unit.

It will be understood by those skilled'in the art that a iiamevtight joint'is a joint which while possibly permitting the passage of gases will cool any ignited gases below the ignition `point so that when the gases escape from the unit,v there is no likelihood of igniting the inflammable gases in the atmosphere in which the unit is being used.

The support I3 is secured in the body against 35A becoming loosened 'on account'of vibration or otherwiseA by means of the'set screw I9 threading through a boss formed on the upper side ofthe support, the end of the screw coacting with the inner Wall of the body, 'as shown inthe drawings. It is to be noted that in the event the receptacle I6, with the wires 31, 3| connected thereto, becomesin any way defective or damaged it may be readily removed from the body together with the support I3 by backingout the set screw VI9 and uns'crewing the support I3 Vfrom the body.

As shown in Figure 1, the upper end of the body is truncated and provided with an opening 20 formed in the inwardly extending iiange 2 I.A IOne half, as 22, of the cable clamp yis formed integral with the ange 2|, the other portion 23 of the clamp being operated by thelscrews 24; The integral portion 22 of the clamp is provided with a grounding screw 25 to which'the grounding conductor oftthe cable 26-is secured.V .i In thisin'- Y In this unit, andasaseneralrule,inthe hand- Y unit ineffective for the purpose fo-rwhich it was stance, where the unit is used as an explosion resisting hand lamp, a handle 21 of rubber or is provided with a suitable vapor tight bushing Yand cable clamp 30.

slipping the handle 21 back on the cable 26, pass-V ing the end of the cable through the Yripening in the body I0, securing the ends of the conu ductors 3| to the receptacle I6. In lighting units of this type, that is, explosionresistingtype, the service wires or leads arev generallysoldered or permanently secured to the terminals in the lamp receptacle. ,This is to avidany? possibility. Yof loose connections.V After the conductors 3| have been properly secured to the receptacle I6, the receptacle ls .seeuredtothezsupport I3 and :the support screwed into the body, The ground Yconductor 32 maythen besecured under the screwV Zifand the handle 21 secured to the ilange 2| and .thebushing tightened.. n

VReferring Vto Figure 2 vof the drawings, the

- upper end. Aof the housing is provided with Ya threaded passage to :receive the threadedxend of a conduit enclosing the service-wires; An opening is provided in one side of the bodyadiacent its Vupper end and a closure or plug v36 threaded into the opening. In wiriu'gfths unit, :the leads ,31. from the receptacle IiiV and the Service Wires, not shown; are broughtv outthrough the 'side opening in the housing, properly connected andreturned through the openinsinto'the upper Cham@- ber of, the body. It it becomes necessarytoreplace thelreceptacle I6 Vin this unit, the leads 31 are disconnected `from the/service wires andthe receptacle ,support I3 is V,unser@awed Vfrom the body.

Ylamp unit shown in Figure 1, the yreceptacle I6 yis provided with leads, andthe receptacle is secured to the supportand the ,sealing compound `run into the well .above the support at the factory. rendering it only necessary for the unskilled workerin charge of the units to unserew the support I3, if necessary .to replace the receptacle, and

to again screw intothe-support and receptacle, thus Vpreventingthe possibility of rendering the intended, .by destroying the seals of the lamp compartment. Y f

The globe 4070i the `fixture which defines the lower portion of the lampcorn-partment isCMrled by a Vglobe Vsupport whichV isdetachably secured .to the loweror open end of the housing l0, As hereV shown, the :support 4I is cylindrical and provided with an inwardly extending flange 42 at its lower end,` the cylindrical portion .being internally threaded, andthe threads being coinplemental to the externally threaded portion I2 of the bod-y Ill.,V 'The .supportlI `also carriesa guard -43 whioh'ls here'rshown as detachably -secured VVto the support by vmeans` of screws 44,

' although, obviously, the support 4 I andthe guard is llstuifllyA .of leader suitable resilient metallic Y material. ',Ihe ange 45 of the globe is" somewhat less'in Vdiameter than Vthe bore of the support 4 I :and extends upwardly Vand inwardly, providing Y Va space 4l `which is lled with a suitablesealing cl'irnpound. preferably .fa compound which .will

This unitmay be wiredfby remain plastic at ordinary temperatures. An externally threaded ring or washer 48 is screwed into the support 4I and seats against the sealing compound. It will be observed that this structure secures the globe to the globe support in such manner as to prevent the escape'of any ignited gases from within the globe, and at the same time permits ready removal of the globe from the support if the 'necessity arises, and alsoV permits expansion and contraction of the outer 'or open end of the globe. VInasm'uch -asthis unit is totally enclosed, and particularly in units of the'smaller size as here shown, the lamp produces an appreciable amount of heat which resultsin considerable vexpansion of the globe 40. lnasmuch as these units must withstand a mine Y imum amount of pressure, usually five hundredk poundsper square inch, it is very important that the glassY globes are not placed under an initial 'strain as they would be materially weakened. kA

globe cools off it contracts andthe yflame/tight joint is still established by the plastic compound.

AVA screw 49 is carriedbythe kbody and arranged to form a lock to prevent `unintentibnal removal of the support 4I `rfrom the body.A As shown lin Figure 1, the guard is provided with a-suitable hook 59 to permit theunit to be suspended from the -outer end, and `in Figure 2, 1.a shade 5I' may be provided, which is secured to the globe support 4|, and :as shown, i clamped between the guard 43 and the support 4I. It'will be observed that thesev units may -be relampedv by simply loosening the screw 49 and unscrewng the support or globe and guard unitirom thebodywith` out, in any manner',- aiecting the joint between the globe and the globe support. However, While the globe and guard unit are secured to the body,` it is impossible to remove the globe from' the globe support.

The arrangement of this structure the structure of the receptacle support Yis to provide a means. whereby the fixture may be maintained by an unskilled .operator without disturbing the flame tightjointY .ofthe unit, which requires some skill, or at leastsome appreciationV o f its value. The globe and support are assembled at thoractory and in the event the globe becomes damaged, a new globey unit is provided, permitting the damaged unit to be returned to the factoryrfor ree conditioning by proper persons. i

WhatIclaim-is: ,Y Y; f' i l. An explosion resisting lighting unit including a body having an internally 'threaded bore, and an externally threaded annular "flange, a receptacle support provided with external'threads complemental to the threads inthe body,a re;V ceptacle -carriedby saidsupport,V a globeand Y l guard unit provided with internal threads com# plemental tothe external threadson the annular flange, a globe and a guard carried by said i unit,rand ahandle r detachably 'secured to theopposite end of the body. Y Y l l g 2. An explosion Yresisting lighting unit including a body open at its ends and having` an internally threaded bore, 'a ikreceptaclelsupport 'threaded into said'bore,and a receptacle vcarried bythe receptacle support, a globe 'supportde-l carried by .the globe Support, .andi-means for detachably securing the globe in said support and forming a flame tight joint between the globe and the support, and a handle secured to the opposite end of the body and forming a closure therefor.

3. An explosion proof lighting unit comprising a body, a receptacle support, means for detachably securing said support in the body, a flame tight joint between the body and the support, a globe support, a globe carried by the support and self-contained therewith, a flame prooi joint between the globe and the globe support including an expansible and contractile plastic packing ring between the globe and its support and capable of expanding and contracting and maintaining the joint during different degrees of temperature, and means for detachably securing the globe support to the body and forming a flame proof joint between the globe support and the body.

4. An explosion proof lighting unit comprising a body, a receptacle support, means for detachably securing said support in the body, a iame tight joint between the body and the support, a globe support, a globe carried by the support and self-contained therewith, a ilame tight joint between the globe and the globe support including an expansible and contractile packing ring and capable of expanding and contracting and maintaining the joint during diierent degrees of temperature, the globe having an annular bead tapering toward the inner end of the globe forming a space V-shaped in cross section between the bead and the globe support, the expansible and contractile packing filling said V-shaped space, and means for detachably securing the globe support to the body and forming a flame proof joint between the globe support and the body.

5. An explosion proof lighting unit comprising a body, a receptacle support, means for detachably securing said support in the body, a ilame tight joint between the body and the support, a globe support, a globe carried by the support and selfcontained therewith, a flame tight joint between the globe and the globe support including a plastic expansible and contractile packing ring between the globe and its support and capable of expanding and contracting and maintaining the joint during different degrees of temperature, the v globe having an annular bead tapering toward the inner end of the globe forming a space V- shaped in cross section between the bead and the globe support, the expansible and contractile packing lling said V-shaped space, resilient means for retaining the expansible and contractile packing in said space, and means for detachably securing the globe support to the body and forming a flame proof joint between the globe support and the body.

6. An explosion proof lighting unit comprising a body, a receptacle support, means for detachably securing said support in the body, a ame tight joint between the body and the support, a globe support, a globe carried by the support and self-contained therewith, a ame tight joint between the globe and the globe support including an expansible and contractile packing ring between the globe and its support and capable of expanding and contracting and maintaining the joint during different degrees of temperature, the globe forming a space V-shaped in cross section between the bead and the globe support, the expansible and contractile packing filling said V- shaped space, a resilient metallic washer between the globe and its support and arranged to cover said V-shaped space and arranged to permit radial expanding and contracting movements of the globe and retain the expansible and contractile packing in said space, and means for detachably securing the globe support to the body and forming a ame proof joint between the globe support and the body.

7. An explosion resisting lighting unit comprising a bell shaped body having an internally threaded bore, a receptacle support threaded in said bore and dividing the body into a service compartment and a lamp compartment, said support being provided on one side with a well to' receive sealing compound, and a receptacle mounted on the other side of said support and extending into the lamp compartment, and a globe and guard unit detachably secured to the body.

8. An explosion resisting lighting unit comprising a bell shaped body open at each end and having an internally threaded bore adjacent the large end, a receptacle support threading into said bore and dividing the body into a service compartment, and a lamp compartment, a receptacle mounted on said support and extending into the lamp compartment and being provided with a well for receiving sealing compound, a globe and guard unit detachably secured to the large end of the body, the smaller end of the body being provided with a cable grip, and a handle detachably secured to the smaller end of the body and forming a closure for the opening therein.

9. An explosion resisting lighting unit comprising a body having an internally threaded bore, a

receptacle support threaded in said bore and dividing the body into a service compartment and a lamp compartment, and eiecting a ame tight seal between said compartments, a lamp receptacle mounted on one side of said support and extending into the lamp compartment, and a globe and guard unit detachably secured to the body.

HAROLD P. HASTINGS.