US2897345A - Electric lamp - Google Patents

Description

July 28, 1959 v. w. MEAGER ETAL 2,897,345

ELECTRIC LAMP Filed April 22, 1957 2 Sheets-Sheet 1 July 28, 1959 v. w; MEAGER ETAL ,3

ELECTRIC LAMP Filed April 22, 1957 2 Sheets-Sheet 2 //v VE/V 70 R5 Verna/x M M ga- 5/uar/ A/. darker United States Patent 2,397,345 ELECTRIC LAMP Vernon Walter Meager, Southampton, and Stuart Nethe'i'woodBarker, Hythe, England Application April 22, 1957, Serial No. 654,290

10 Claims. or. 240-1058 This invention relates to electric lamps and more particularly to battery lamps of the self-contained type,

commonly known as flashlights.

character, comprising a casing fitted with a removable cap orco'llar made of resilient material, which normally holds the parts together, this collar and the part holding the lamp "bulb being rotatable in relation to the casing to effect switching of the lamp circuit and also movable axially or by tilting in relation to the casing in order to provide for intermittent illumination of the lamp.

Yet another object is to provide an improved lamp -of this character, wherein the contact-making elements 'canbelocked against engagement byfurther rotation of thecap or collar to a position at which the axial movement is prevented.

A further object is to provide an improved lamp of this character which is "substantially air-tight so as to prevent theentranceof damp, water and dust, and wherein the compression of the enclosed air by axial move mentof the cap 'or collar is relieved so as not to oppose the axial movement, this being achieved without atfectingthe air-tightness ofthe lamp.

Other objects and advantages of the invention will hereinafter appear from the following description of a preferred embodiment, given with reference to the accompanying drawings, in which:

Fig. 1 is an elevation, in half section, of an electric battery lamp or flashlight in the on position.

Fig. 2 is an enlarged detail showing the parts in the off position, after partial rotation of the collar and reflector in relation to the casing.

Fig. 3 is a similarview showing the parts in the on position, after axial movement of the collar and reflector in relation to the casing.

Fig. 4 is a similar detail showing the parts in the locked oe position.

Fig. 5 is an end view of the lamp casing, as seen from the left of Fig. 'l, the collar, front glass and reflector being removed.

Fig. 6 is a rear view of a carrier ring for three insulating pads, and Fig. 7 shows-one of these pads removed.

Fig. '8 is a'sectionalclevation of the reflector.

Figs. -9 and 10 are sectional elevations of contact members normally attached to the reflector.

"FigLll is an end view "of the reflector, as seen from the'right of Fig. 8 Withthese contact members attached.

sist of an aluminum-alloy casting, comprises a cylindrical portion 10 forming a casing for the battery or batteries 11, closed at one end 12 and open at the other end, the open end being flared outwardly as at 13 to provide a cylindrical extension 14 of larger diameter. Within the flaring portion 13 of the body, there are provided three evenly spaced lugs 15, beyond which the extension 14 is bored out to form a shoulder 16. A metal ring 17 of angle-section is fitted tightly into the extension 14 and against the shoulder 16, being secured by any conventional means; the inner flange of this ring is divided, as seen in Fig. 5, by three gaps 18 spaced evenly apart and located between the lugs 15, the back of this flange thus forming three arcuate ledges 19, each of which has a radial wall 20 at one end. Between these ledges and the lugs 15, there are fitted three insulating pads secured in place by adhesive or by pinning; each of these pads comprises an arcuate check 21 partly recessed into the face of the ledge and a shorter check 22 fitting against the lugs 15, the two cheeks being made separate or connected together at one end of the ledge. The check 21 extends for about three-quarters of the angular length of the respective ledge 19, and its exposed face is divided by substantially radial humps into two sec tors, the remaining portion of the ledge adjacent the Wall 20 being stepped up approximately flush with the end of this check.

The pad-carrier 17, which is fixed in relation to the lamp body, co-operates with a rotatable reflector or lamp head 23 for switching the lamp on and off by relative rotary movement; the reflector, shown separately in Figs. 8 and 11, comprises a central socket 24 for bold ing the lamp-bulb 25, which may be of screw type or push-in type, and it is provided with a flanged rim 26, having an inner flat face parallel with the outermost edge of the extension 14 at the open end of the lamp body. The reflector 23, including its socket 24 and its flanged rim 26, may be made in one piece of aluminum alloy, being preferably fitted with a polished metal liner 27; it is covered by a separate front glass 23. The reflector rim 26 and the front glass 28 are engaged in in ternal annular grooves 29, 31 respectively within a cap or collar 31 made of rubber or like resilient material, which is rotatable together with said rim and front glass in relation to the lamp body. The collar is formed with an approximately cylindrical flange 32, which fits around the extension 14, the flange '32 being relatively thin and terminating in a bead 33; this bead is preferably circular in cross-section and slightly smaller in diameter than the extension 14, upon which it therefore grips tightly to ensure water tightness of the collar 31, without however preventing relative movement as required for switching the lamp on and off.

The reflector or lamp head 23 is provided with a contact member preferably made in the form of a spider 34 attached to the base 3S of the reflector, as by screws, and having three evenly spaced contact arms 36; these arms project beyond the circumference of the base to positions where 'they may co-operate with the carrier ring 17 for closing the lamp circuit or with the insulating pads 21, 22 on this ring for interrupting the circuit, the extremities of the armsbeing preferably bevelled on their edges.

As seen in Fig; l, the contact arm 36 engages directly with the carrier ring, so as to close the circuit, all three contact armsbeing similarly engaged with the ring under the axial pressure of the spring 37 maintaining the batteries'in engagement with the lamp 25; this pressure will be evenly distributed upon the three arms. Upon rotation'of the reflector 23 by means of the rubber collar 31, for interrupting the lamp circuit, the arm 36 is moved from engagement with the ring 17 and brought onto the end ofthe check 21 of the insulating pad, as

0.9 seen in Fig. 2, all three contact arms being similarly moved onto the insulating pads. In this position, however, the lamp may be brought back into operation, as for temporary or intermittent illumination, by pressing the reflector 23 axially towards the lamp body, thereby bringing the rim 26 of the reflector into contact with the open end of the extension 14, as seen in Fig. 3; it will be suflicient to tilt the reflector, as by pressure at one point of the collar 31, in order to establish the circuit, which will be interrupted as soon as such pressure is removed. By further rotary movement of the collar and reflector 23, each of the contact arms 36 may be brought into the position shown in Fig. 4, where the arm is engaged between the two cheeks 21, 22 of the insulating pad, all three arms 36 being similarly engaged in their insulating pads 21, 22; in this position, therefore, the lamp is positively locked out of operation, and no axial or tilting pressure will serve to close the circuit, the locked position being therefore advantageous in cases where the lamp has to be stowed with possibility of axial or tilting movement or end pressure.

The base portion 35 of the reflector or lamp body is shown provided with an insulating sheath 38 to obviate risk of accidental closure of the circuit by contact between this base and the interior of the carrier ring 17 which is in conductive connection with the casing or body.

With the reverse direction of rotation, the arms as will be brought from the locked position (Fig. 4) between the cheeks 21, 22 of their insulating pads, first into the open-circuit position (Fig. 2) where they press against the longer cheeks 21 of the pads, and secondly by further rotation into the closed-circuit position (Fig. l) where they will press against the carrier ring 17 and thus cause the illumination of the lamp. By still further rotation, the contact arms may be lifted over the walls 20 and brought into alignment with the gaps 18 between the ledges 19 of the carrier ring; in this position they will allow the reflector or lamp head 23 to be withdrawn from the lamp body, together with the rubber ring 31, for example if required to replace the battery or batteries 11 or the lamp bulb 25.

Due to the tight engagement of the collar flange 32 with the exterior of the extension 14, axial movement of the reflector 23 in relation to the lamp body for intermittent illumination may be resisted by slight compression of the enclosed air, but this can be relieved by displacement of air from the interior into the thin flange 32, which expands to form a bulge 39, as indicated in Fig. 3, without aflecting the tightness of the closure eflected by the cylindrical bead 33, which can roll in place. It will be understood that on the axial return of the reflector to its normal position, the displaced volume of air can leave the bulge 39 in the flange and re-enter the lamp body.

During the fitting of the collar 31 and lamp head 23, the air enclosed in the lamp body will similarly be subject to a slight compression, which can be accommodated by the bulge in the flange until the pressure falls again, when the contact arms 36 are in their normal position; upon removal of the rubber collar, appreciable suction may occur within the lamp body, resulting in a rather sudden release of the collar and the possible jerking of the batteries 11 out of the casing; this may be avoided by the provision of small vent holes as shown at 40, sufficient to reduce the vacuum gradually as the collar is pulled oif.

In addition to the contact members 34, 36, the reflector also carries a contact member consisting of a soft metal stud or rivet 41 normally interposed between the center pole of the lamp bulb 25 and the center pole of the adjacent battery 11, in order to avoid wear at the lamp contact, due to tilting or rotary movement of the reflector, and possible unscrewing of the lamp bulb, due to the rotary switching movement. This contact member or stud 41 is carried by a plate 42 made of insulating material such as fibre, secured upon the base 35 of the reflector, so that the stud turns to and fro together with the reflector and lamp bulb.

The improved battery lamp is substantially waterproof and also proof against gas, flame and dust, so that it is particularly suitable for use in mines and other places where there is danger of explosion caused by sparks at electrical contacts; in order to prevent unauthorised removal of the resilient rubber cap 31 and consequent opening up of the lamp under such circumstances, means may be provided for locking the cap in position, while allowing its rotary or axial movement. For example, as shown in Fig. 12, there may be fitted over the head of the lamp a safety ring 43, made in two halves locked together in position by screws 44, of a suitable type which requires a special key or spanner for their release; provision may also be made for a sealing wire to prevent the removal of the safety ring.

The lamp body or casing 10, the inserted carrier ring 17, the reflector or lamp-head 23 and the contact member 34 may be manufactured as mouldings, castings, stampings or spinnings of sheet metal; it will be understood that the invention is not limited to the particular embodiment described and illustrated, but may be modified to suit various conditions of use, within the scope of the appended claims.

What we claim is:

1. An electric lamp, comprising a metallic batterycasing having an open end, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar having a flange fitting around said open end and having an outwardly extending portion supporting said rim normally concentric with and in condition for rotation relative to said casing, and contact means for closing the battery circuit to said lamp bulb by relative rotation of said casing and reflector, said reflector rim being normally spaced from said open end and forming alternative contact means for closing said circuit by relative axial movement instead of relative rotation of said casing and reflector whereby the battery circuit to said lamp bulb may be intermittently closed by moving said reflector rim into engagement with said casing.

2. An electric lamp, comprising a metallic batterycasing having an open end, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar having a flange fitting around said open end and having an outwardly extending portion supporting said rim normally concentric with and in condition for rotation relative to said casing, contact arms in connection with said socket, said contact arms being spaced angularly around said reflector, and con tact surfaces spaced angularly around inside said open end, said contact arms being engaged with said contact surfaces for closing the battery circuit to said lamp in one rotary position of said reflector relative to said casing, and said reflector rim being normally spaced from said open end in another rotary position but engageable therewith by tilting motion for alternatively closing said circuit.

3. An electric lamp, comprising a metallic batterycasing having an open end, a metallic ring secured to said casing inside said open end, said ring having an inner surface gapped at evenly spaced points of its circumference, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar having a flange fitting around said open end and having an outwardly extending portion supporting said rim concentric with and in condition for rotation rela-' tive to said casing, and contact means for closing the battery circuit to said lamp byrelative rotation of said casing and reflector, said reflector rim being normally spaced from saidopen end and forming alternative means for closing said circuit by relative movement of said casing and reflector against the spacing action of said resilient collar whereby the battery circuit to said lamp bulb may be intermittently closed by moving said reflector rim into engagement with said casing.

4. An electric lamp, comprising a metallic batterycasing having an open end, a metallic ring ofangle-section secured inside said open end, said ring having its inward flange formed with gaps spaced equally around its inner edge, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for alamp bulb, said rim'being of external diameter at least equal tothat of said open end, a resilient collar having a flange fitting around said open end and having an outwardly extending portion substantially concentric with and incondition for relative rotation with respect to said casing, contact arms in connection with said socket, said contact arms being spaced angularly around said reflector, the angular spacing of said contact arms being the same'as that of said gaps whereby the arms are axially in line with the gaps in said ring flange in one position of said reflector relative to said casing and with intermediate portions of said ring flange in other positions of said reflector relative to said casing, and insulating means'for holding said contact arms from said intermediate'ring flange portions in one of said other relative positions of said reflector, partial rotation of said collar and reflector relatively to said casing determining the engagement of said contact arms with said intermediate ring flange portions for closing the lamp circuit or with said insulating means for interrupting said lamp circuit, said reflector being normally spaced from said casing, said resilient collar and reflector being axially movable in relation to said casing for engaging said reflector rim with the edge of said open end for intermittently closing said lamp circuit.

5. An electric lamp, comprising a metallic batterycasing having an open end, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar having a flange portion fitting around said open end and having an outwardly extending .portion supporting said rim concentric with and in condition for rotation relative to said casing, contact means for closing the battery circuit to said lamp bulb by relative rotation of said casing and reflector, said reflector rim being normally spaced from said open end and forming means for intermittently closing said circuit by relative tilting movement of said reflector and casing whereby the battery circuit to said lamp bulb may be intermittently closed by moving said reflector rim into engagement with said casing, said flanged portion having a terminal bead fitting in an air-tight manner around said open end, said casing having an opening formed therethrough adjacent an intermediate portion of said flange and being in communication with the interior of said casing, said flanged portion being expansible to accommodate air displaced through said opening from the interior of said casing by said axial movement.

6. An electric lamp, comprising a metallic batterycasing having an open end, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar holding said reflector rim concentrically with and in condition for rotation relative to said casing, a transparent front for said reflector, said resilient collar having a relatively thin flange fitting around said open end, said collar having an outwardly extending portion in sealing engagement with said transparent front to render said casing'substantially air-tight, contact means for closing the battery circuit to said lamp bulb'by relative rotation of said casing and reflector, said reflector rim being normally spaced from said open end and forming means for intermittently closing said circuit by relative axial movement ofsaid reflector and casing to bring said rim into engagement with the edge of said open end, said casing having an opening formed therethrough adjacent an intermediate portion of said flange and being in communication with the interior of said casing, said relatively thin flange of said resilient collar being expansible to accommodate air displaced from the interior of said casing by way of said opening by said axial movement.

7. An electric lamp, comprising a metallic battery-casing, said casing having an open end, a metallic ring secured inside said open end, said ring having an inner surface gapped at equidistant points around the circumference, insulating pads mounted upon a portion of said ring between said gaps, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of external diameter at least equal to that of said open end, a resilient collar having a flange fitting around said open end and having an outwardly extending portion supporting said rim concentric'with and in condition for rotation of said reflector relative to said casing, and contact arms carried by said reflector for closing the battery circuit to said lamp bulb through said metallic ring in one rotary position of said reflector relative to said casing, said contact arms engaging with said' insulating pads in another rotary position of said reflector, said reflector rim being normally spaced from said open end and engaging with said open end for intermittently closing the battery circuit to said lamp bulb by tilting movement of collar and reflector in relation to said casing instead of rotation relative thereto.

8. An electric lamp, comprising a metallic batterycasing, said casing having an open end, a metallic ring secured inside said open end, said ring having an inner surface gapped at equidistant points around the circumference, insulating pads mounted upon a portion of said ring between said gaps, a metallic reflector of a size to enter said open end, said reflector having an external rim and a central socket for a lamp bulb, said rim being of (external diameter at least equal to that of said open end, a resilient collar holding said reflector rim concentric with and in condition for rotation relative to said casing, a transparent front for said reflector, said resilient collar having a relatively thin flange fitting around said open end to render said casing substantially air-tight and having an outwardly extending portion supporting said rim for holding said rim normally spaced from said open end and in condition for rotation relative to said casing, and contact arms engaging with said insulating pads in another rotary position of said reflector, said reflector rim being engageable with the edge of said open end for intermittently closing the battery circuit to said lamp bulb by axial movement of collar and reflector in relation to said casing, said casing having an opening formed therethrough adjacent an intermediate portion of said flange and being in communication with the interior of said casing, said relatively thin flange of said resilient collar being expansible to accommodate air displaced from the interior of said casing by way of said opening by said axial movement.

9. An electric lamp comprising a battery case of electrically conducting material closed at one end and having towards the other end an outwardly flaring portion which merges into a short cylindrical portion of larger diameter than the remainder of said case, said short cylindrical portion terminating in a rim lying in a plane transverse to the longitudinal axis of said case, a helical metal spring (in the interior of said case abutting the closed end, a

battery enclosed in said case and abutting said helical spring, an outwardly facing internal annular shoulder located near the junction of said flaring and short cylindrical portions, a metal ring fitting within said short cylindrical portion and abutting said shoulder, said ring having at least three equi-angularly spaced slots therein extending as far as said shoulder, electrically insulating material located between said metal ring and said out wardly flaring portion, said insulating material including at least three equi-angularly spaced notches and intermediate camming surfaces, a concave reflector unit of electrically conducting material having a terminal rim of diameter substantially equal to that of the terminal rim of said short cylindrical portion, said reflector unit including a central lamp holder, a lamp bulb in said lamp holder, said lamp bulb having an electrode in contact with said battery, a spider of electrically conducting material aflixed to the rear of said reflector unit and including a plurality of arms spaced in the same angular relation as the slots in said annular ring, said arms being dimensioned so as to be capable of being entered into said slots and then rotated over said cammed surfaces when said reflector unit is engaged in said case, so that partial rotaticn of said reflector unit relative to said case will retain said arms behind said ring and also control the flow of electric current by said arms to said lamp bulb, a circular front glass for said lamp having a diameter equal to that of the terminal rim of said short cylindrical portion, and a cylindrical member of resilient and electrically insulating material having at least one internal annular groove dimensioned to receive said front glass and said reflector unit in sealing relationand having a skirt extending over the outside of said short cylindrical portion for supporting said reflector unit normally parallel to but spaced from the terminal rim of said short cylindrical portion and in fluid-tight relation thereto, axialmovement of said reflector unit towards said case by distortion of. said resilient cylindrical member bringing the terminal rim of said reflector unit into electrical contact with the terminal rim of said short cylindrical portion to provide an alternative path for the flow of electric current to said lamp bulb for intermittent illumination of said lamp bulb.

10. An electric lamp according to claim 9, wherein said electrically insulating material includes at least three arcuate cheeks, angularly spaced, the cheeks of each pair being of diiferent angular lengths, the longer checks in cluding said camming surfaces and the shorter cheeks pro- ,viding gaps through which said spaced arms can be entered for partial rotation over said camming surfaces and between said cheeks.

References Cited in the file of this patent UNITED STATES PATENTS 1,342,322 Boulanger June 1, 1920 2,204,136 King et al June 11, 1940 2,234,972 Lennan Mar. 18, 1941 2,272,907 Deibel Feb. 10, 1942 2,367,888 Prideaux Jan. 23, 1945 2,427,017 Miller Sept. 9, 1947 2,483,665 Phillips Oct. 4, 1949 2,518,437 Amstutz Aug. 15, 1950

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