US2727984A

US2727984A - Latch device for closed type luminaire

Info

Publication number: US2727984A
Application number: US184254A
Authority: US
Inventors: Robert L Smythe; Donald W Harling
Original assignee: McGraw Electric Co
Current assignee: McGraw Electric Co
Priority date: 1950-09-11
Filing date: 1950-09-11
Publication date: 1955-12-20
Anticipated expiration: 1972-12-20

Description

Dec. 20, 1955 R. sMYTHE Erm.

LATCH DEVICE F'OR CLOSED TYPE LUMINAIRE 2 Sheets-Sheet l Filed sept. 11, 195o maak I N V W @gm De@ 20, 1955 R. L.. sMY'rHE rs1-A1.

LATCH DEVICE FOR CLOSED TYPE LUMINAIRE 2 Sheets-Sheet -2 Filed Sept. l1, 1950 Fiql INVENTO M A ORNEY 6. MM mn 5m lMw. T. m Bl 0 M f United States Patent O LATCH DEVICE FoR CLOSED TYPE LUMiNAmE Robert L. Smythe and Donald W. Harling, Milwaukee,

Wis., assignors to McGraw Electric Company, Mllwaukee, Wis., a corporation of Delaware Application September 11, 1950, Serial No. 184,254

2 Claims. (Cl. 240-147) This invention relates to improvements in hinge and latch devices for closed type luminaires and the like.

Automatic latching devices for street luminaires are well known. However, such devices do not fulll all of the needs. For instance, they have not heretofore been strictly automatic, in that they often require adjustments to compensate for vertical variations in the glassware anges and necessitate additional latching operations. These adjustments have heretofore been made with screws, gasket layers, etc.

lt is very important that there be a seal between the reliector and glassware portions of the luminaire in order to prevent bugs, dust, water, etc. from entering the luminaire. Naturally, it is a distinct advantage to provide the necessary seal without gaskets or other special devices.

Also, a good share of the maintenance operations are performed from the street level using operating sticks provided with various adapter tools attached thereto. Heretofore, it has been necessary for the operator to close the unit by pressing against a latch with a special adapter tool. Many operators, in order to expedite matters, prefer to press against the glassware itself, which has often resulted in disalignment of the sealing surfaces and improper latching. ln addition to the problem of maintaining a tight seal, disalignment also introduces the problem of increased glassware breakage.

This invention is designed to overcome the above-noted defects, and objects of this invention are to provide a fully automatic latching -device for street luminaires and the like, that will permit a tight seal between the globe assembly and the reilector of the luminaire without the necessity of using gaskets, and without requiring special eiort to insure a tight seal, and which will secure and maintain uniform pressure at all points along the glassware flange circumference.

Another object of this invention is to provide an automatic, self-aligning latching device for luminaires that will permit maintenance of the luminaire by a workman standing on the ground at a distance from the luminaire greater than aims length by the use of operating sticks with suitable attachments.

A further object of this invention is to provide ari automatic latching device for luminaires that is rigidly secured to the glassware, permitting relatching of the luminaire on completion of maintenance operations by hand pressure applied to the globe portion.

Still another object of this invention is to provide an automatic latching device for luminaires that will permit self-alignment of the luminaire globe within the luminaire without any further adjustments during or after relatching.

A still further object of this invention is to provide an automatic co-acting hinge and latch device for releasably holding twov assemblies in sealing relationship where a uniform latching pressure is desired without the necessity for providing sealing gaskets or the like.

In the drawings:

Fig. l is a fragmentary view, partly in section, of a closed type street luminaire embodying the novel hinge and latch device.

Fig. 2 s anenlarged side view, partly in section, showing the hinge device.

Fig. 3 is a front view of the hinge device.

Fig. 4 is an enlarged side View, partly in section, showing the latch device in normally latched position.

Fi g. 5 is a front View of the latch device, partly in section, taken on line 5-5 of Fig. 4.

Fig. 6 is an enlarged side View, partly in section, of the latch device, showing the latching lever arm n full open position, and further showing the lower assembly engaging the latch lever immediately prior to movement of the various parts to normally latched position.

Fig. 7 is a side View of the globe retaining band showing the clamping means, pivot support, and latching prong.

Fig. 8 is an enlarged sectional view showing the upper and lower assemblies in sealing relationship.

Fig. l shows a closed type street luminaire assembly including a reflector or housing 1 and a glass globe 2 which is supported by a globe retaining band or ring 5. This lower assembly is secured to the rellector 1 by means of a hinge device designated generally by the numeral 3, and a latch device designated generally by the numeral 4.

The rellector 1 is provided at its lower end with an integral ange 6 which is more clearly shown in Fig. 8. The ange is strengthened by forming the lower rim of the reflector substantially twice the length of the nally desired flange height and spinning one layer back upon itself. Other strengthening means may also be used, such as separate backing strips fastened to the flange portion (not shown).

The globe band S is preferably cast of a single length of suitable thin gauge, i'lat metal provided with a latching prong 7 integral with the band, or secured to the band in any convenient manner. The band 5 is mounted adjacent the upper edge of the globe 2 and may be secured to the globe as shown in Figs. 1 and 7. Fig. 7 clearly shows the well-known method, indicated generally by reference character 5a, of joining the ends of the globe band by means of a machine screw and nut positioned through projecting portions on each of the open ends., Although a split ring is indicated herein, it will be apparent that a retaining band may be provided whichis divided into half portions with both sides joined as described above. lt will also be apparent that the ring may be of a solid construction (not shown) that may be slipped over the globe 2 and held rigidly to the globe by one of many The hinge device is clearly shown in Figs. 2 and 3.

Pivot supporting members 8 are provided diametrcally opposite the latching prong 7, and are preferably cast integral with the globe band 5. A pintle pin 9 extends between the pivot supporting members 8, and is preferably made of tubular material ilared at both ends. The pintle pin 9 is suspended from the hinge support spring 10. The hinge support spring 10 is preferably made U-shaped and extends across the pivot supporting members 8 as shown in Fig. 3. assembly and to resiliently bias both the reector and globe assemblies towards sealing relationship. It will be apparent that the globe may be resiliently supported n other ways not shown herein.

The ends of the pin 9 are ared or peened against the washers 11. This flaring is made tight enough to hold the spring 10 in a substantially rigid manner extending in a position normal to the band 5. The spaced arms of This spring serves both to support the globe the U-Shaped Spring are preferablvformedwith 3.10012 12, in order to give the spring the desired degree of resiliency. It will be apparent: that other means may be provided for giuingthe supportingy arms ofthe springthe desired degree of resiliency. These have not beenl shown, i

butrnight includeqwinding the arms in; a spiral coil or forming them in the shape of a C. l

A hinge member isgsecured tothe ange 6 of recctor 1v withscrews ,16, engagingtapped screw plates or nuts (not shown), :Thehinge member 15 is provided with notched portions 20.' These notches receive and' support the crossarm portion of the'` U-shaped spring 10', permitting easy removal and replacement ofthe globeassembly. A slot 21`r isprovided to, receive the pintle pin 9 of.

globeband 5.-The-lip portionV 22y is provided to permit theV pin. 9 to have'easy access( tvo-the slot 21 prior to 'positioning spring 1.0 inernotch 20..y

The. slote21 ismade of such length that it will permit fr ee guided movement of the. pin 9 without permitting the pin to roll: past thhe lip portion 22 Whenthe globe 2 is v reference.V to Figs. 4, 5` and 6. The device 4'is preferably positioned substantially diametric to the hinge 3 as is shown in Fig. 1,1and consists essentially of four parts; the latchingprongj Yof globe retaining band 5, the latch support 25, lthe latch spring 26, and a lever arm 27.

'lhelatchv supportrmember 25 is preferably fastened to thel ange 6 of reflector 1 with screws 28 engaging with tapped holes ina reinforcing screw plate on the reverse sideofsaid flange (not shown). The latch support member. 25. issubstantially U-shaped with a stopping web portion. 30 integrally positioned between the spaced arms of the member 25..V The latch spring 26 is preferably substantiallyV identical tothe hinge spring 10, and is fastened tothe. support member with the arms of the essentially U-shaped springrp26- being fastened to either side of the latch. hinge-by means of a flared pin 31. Both ends of the pin. 31 are flared or peened against thewashers 32. A lever.y armr 27 is` pivotally supported by a pin 33 which extends between the spaced arms of the support member 25.. The spring- 26.4is seated in the slotted portion 34 of lever armv 27 normally urging the lever arm in a clockwise direction about the pin 33 as is shown in Fig. 4. The. lever arm 27is further provided withY integral latching webportions. 36 and 37.

Referring to Fig.,6v, itV will be seen'that the spring 26 is designed.. and positionelv to loperate in Van over-center manner.. Thus, as-the lever arm 27 is moved Yto unlatched position as hereinafter -be described,` the spring 26 Y will act. to urge the lever in a counter-clockwise direction.

Thenovel hinge and latch device operates as follows: The. lever arm- 27 may be operated by-hand or with an adapterA tool fitted. to the free end of a standard operating stick. Assuming the globe 2 to rbe in closed position,v as showngin Eigwl, the lever arm 27 is moved in a counter-clockwisedirection about the pivot pin 33 until further motion isfpreventedY-by the stopping web portion 30. The spring-,26will be simultaneously moved to overcenter position Where it will urge the arm in a counterclockwise direction as isshown in Fig; 6. AAs the arm 27 is moved, -the-web portion4 37. presses downwardly against the latching prong 7 of globe band 5. Simultaneousl'y. thelatchingawe'b willbe movedfaway from the latchingfprong 7zand the globe assemblywill d rop down in a clockwisedire'ction aboutthe Vhinge 3. v

The supporting members 8 are preferably designed as shown in Fig.l 2 so that they willcollide with thehingeY member 15 when the globe 2 swings down to open position. Thus, the support spring 10 will be prevented from disengagement at the notched portion 20 of hinge member 15. It will be apparent that the globe assembly may be easily removed for maintenance care by further clockwise motion about the notched portion 20. This motion will cause the pin 9 to move upwardly'out of the slot 21 and over the lip 22. The globe assembly may then be lifted on of the hinge member 15. n

The globe may be brought to closed position in either of two methods after repositioning of the pin 9 in the slot 21 and engagement of the support: springv 10; with the notch 2i). An attachment ltted to the operating stick f (not shown) may be abutted against the globe band 5, and the globe assembly pushed upward with the upper shouirler of the Viatching prong 7 engaging the latching web 37 as is shown in Fig. 6. Increased pressure'onthe globe assembly will be transferred to the weby 37 andi accordingly urge the lever arm 27 to latching position as shown in Fig. 4, the prong 7 resting on the web 31S.4 During the latching operation the spring 26' will mover over-center rom unlatched position as shown in Fig. 6` to latched position as shown in Fig. 4.

The luminaire may also be closed by hand. pressure: applied to the globe itself. Since the globe 2 is rigidly' supported by the globe retaining band 5 as isv shown in S, and does not in any way float in the retaining band, the upper surface of the globe and theY latchng`y prong 7 will move simultaneously to provide a tight,-

dust-free closure between the globe and the reector 1v when latching prong is in normally latched position supported by the web 36 of lever arm 27. The hinge spring itl and the latch spring 26 provide a uniform..

pressure, forcing the globe band, along with the rigidly. held globe 2, in sealing relationship with the under. surface of the ilange 6 of reflector 1. that no sealing gasket is necessary. against the globe 2 will not in any way move the globeu out of the globe retaining band 5.` Thus, any possibility of glassware chipping or tilting of the globe in a luminaire.

will be eliminated. It will be obvious that the globe may'. A be rigidly supported in any of other well-known, ways.

For instance, the retaining band 5 may be designed'to project above the glassware itself. (not shown) so that the upper edge of the band will engage the sealingsurface p of the flange 6 of reflector 1.

improper latching is prevented by rigidly mounting.

the globe 2 in the retaining band 5, which is obviously a distinct advantage. It will be apparent from Fig. 6V tliat` should the globe 2 and the retaining band` 5 not move as a unit, application of hand pressure to the globe during closing operations might cause the. globe to contact the iiange 6 prior to engagement of the latching prong17 with the web 37. This would result in improper latcliing, disalignment of the globe, and possible breakage of the glassware. The novel hinge and latch device willpermit fully automatic latching without the need for additional adjustments subsequent to closure.

The novel device works effectively on all types of street light luminaires, but it is not necessarily limited to this.

It will be apparentk Hand pressure a movable assembly and hinge means for pivotally and resiliently supporting said assemblies towards sealing relationship, an automatic latch comprising in combination a latch prong integral with said movable assembly, a latch support member integral with said stationary assembly, a U-shaped spring member having spaced arms and being pivotally suspended by said latch support member at the extremities of said arms, each of said arms including an integral resilient coil portion, a latch lever arm pivotally supported by said latch support member at a point spaced from the spring pivot point, said lever arm being recessed to receive the base portion of said U-shaped spring member at a point eccentric of the pivot point of said lever arm, said latch lever arm having a second recessed portion having spaced inner surfaces adapted to alternatively engage and disengage said latch prong to respectively concurrently draw said assemblies towards sealing relationship and to initially separate the assemblies after sealing on manual operation of said lever arm towards unlatch position.

2. En a luminaire comprising a stationary assembly, a movable assembly' and hinge means for pivotally and resiliently supporting said assemblies towards sealing relationship, an automatic latch comprising in combination a latch prong integral with said movable assembly, a latch support member integral with said stationary assembly, a U-shaped spring member having spaced resilient arms and being pivotally suspended by said latch support member at the extremities of said arms, a latch lever arm pivotally supported by said latch support member at a point spaced from the spring pivot point, said lever arm being recessed to receive the base portion of said U-shaped spring member at a point eccentric of the pivot point of said lever arm, said latch lever arm having a second recessed portion having spaced inner surfaces adapted to alternatively engage and disengage said latch prong to respectively concurrently draw said assemblies towards sealing relationship and to initially separate the assemblies after sealing on manual operation of said lever arm towards unlatch position.

References Cited in the tile of this patent UNITED STATES PATENTS 994,427 Ross June 6, 1911 1,269,467 Leonard et al lune 11, 1918 1,335,958 Farr Apr. 6, 1920 1,653,280 Herwig, Jr., et al Dec, 20, 1927 1,848,276 Smythe et al Mar. 8, 1932 2,309,279 Smythe Ian. 26, 1943 2,344,327 Runge Mar. 14, 1944 2,434,241 Craig Ian. 13, 1948