US3769501A

US3769501A - Selective actuating mechanism for percussive photoflash lamp array

Info

Publication number: US3769501A
Application number: US00320007A
Authority: US
Inventors: Donough T Mc
Original assignee: GTE Sylvania Inc
Current assignee: GTE Sylvania Inc
Priority date: 1973-01-02
Filing date: 1973-01-02
Publication date: 1973-10-30
Anticipated expiration: 1990-10-30

Abstract

For a photoflash assembly comprising a plurality of percussively-ignitable flashlamps arranged in an array with respectively associated reflectors and preenergized striker springs, a self-energized selective actuating mechanism for sequentially releasing the striker springs to fire respective flashlamps in response to successive indexing. The actuating mechanism includes a coplanar train of intermeshing spur gears having a number of circumferentially spaced projecting ramps. The lamps and striker springs are supported on the end surfaces of shafts upon which the gears are mounted, with the strikers radially projecting over the surrounding gear to lie in the path of travel of the ramps. A spring-loaded, sliding rack gear is enmeshed with one of the spur gears and is position-controlled by a spring-loaded, pivoted arm having a pin engaging a sawtooth slot cam in the rack gear. To flash a lamp, the pivoted arm is raised so that the cam-engaging pin clears a vertical portion of the sawtooth slot and thereby releases the spring-loaded rack gear to rotationally index the gears while the cam-engaging pin rides down a ramp portion of the sawtooth slot. The gear indexing permitted by the pitch of the sawtooth slot causes one of the ramps to release a striker.

Description

United States Patent [1 1 McDonough 1451 Oct. 30, 1973 SELECTIVE ACTUATING MECHANISM FOR PERCUSSIVE PHOTOFLASH LAMP ARRAY [75] Inventor: Thomas B. McDonough, Allenwood,

[73] Assignee: GTE Sylvania Incorporated, Danvers, Mass.

22 Filed: Jan. 2, 1973 21 Appl. No.: 320,007

[52] U.S. Cl...; 240/l.3, 95/11 L, 431/93 Germany 240/1 .3

Primary Ex'aminerFred L. Braun AttorneyNorman J. OMalley [57] ABSTRACT For a photoflash assembly comprising a plurality of percussively-ignitable flashlarnps arranged in an array with respectively associated reflectors and preenergized striker springs, a self-energized selective actuating mechanism for sequentially releasing the striker springs to tire respective flashlamps in response to successive indexing. The actuating mechanism includes a coplanar train of intermeshing spur gears having a number of circumferentially spaced projecting ramps. The lamps and striker springs are supported on the end surfaces of shafts upon which the gears are mounted, with the strikers radially projecting over the surrounding gear to lie in the path of travel of the ramps. A spring-loaded, sliding rack gear is enmeshed with one of the spur gears and is position-controlled by a spring-loaded, pivoted arm having-a pin engaging a sawtooth slot cam in the rack gear. To flash a lamp, the pivoted arm is raised so that the cam-engaging pin clears a vertical portion of the sawtooth slot and thereby releases'the spring-loaded rack gear to rotationally index the gears while the cam-engaging pin rides down a ramp portion of the sawtooth slot. The gear indexing permitted by the pitch of the sawtooth slot causes one of the ramps to release a striker.

18 Claims, 7 Drawing Figures S 30 34 :8 &\ 1o. 10 i 32 \se 096 5 Y .zgqa 2s 58 '5 ze {*6 34 34 6 '9. i

46 45 46 ,Z.' 3' OJ 34 56 I r7 66 60 78 72 so 4 FEJETFU'UQQJ 9o- 82 ge 74 16 SELECTIVE ACTUATING MECHANISM FOR PERCUSSIVE PHOTOFLASH LAMP ARRAY BACKGROUND OF THE INVENTION tability. A currently popular flash lamp unit of this type is known generally in the trade as flashcube, a specific embodiment of which is shown in US. Pat. No. 3,327,105, for example. The unit comprises a set of four flashlamps, each with its own reflector, mounted on a base and enclosed within a transparent cover, with I 7 each of the lamp-reflector assemblies facing a respective one of the four side walls of the cube. A spindle depends from the center of the flashcube base for operatively retaining the unit in a complementary receiving socket on a camera. In operation, the flashcube is sequentially rotated a quarter of a turn at a time, usually in response to each operation of the film advance mechanism of the camera, to successively place unused lamps in a firing position facing the object being photographed. Each of the flashlamps consists of an hermetically sealed, light transmitting glass envelope containing a filamentary combustible material, such as shredded zirconium foil, and a combustion supporting gas, such as oxygen. In the case of flashcubes employing electrically ignited lamps, a pair of lead-in wires pass through the lamp envelope to support therein a fila ment in combination with globules of ignition paste. When the flashcube is in the firing position, segments of the lead-in wires disposed outside the lamp envelope are securely engaged with electrical contacts in the camera socket, which in turn are connected by wires and a shutter actuated switch to the camera power source, usually a pair of dry cell batteries. When a photographer actuates the shutter release mechanism to snap" a picture, he also, by the same operation, closes the electrical circuit from the batteries to the ignition system in the lamp to thereby flash the lamp. The timing of the ignition of the combustible material in the lamp is synchronized with the exposure of the film by actuation of the shutter release so that efficient utilization of the light from the flashlamp may be obtained.

A not infrequent problem that has been faced by the average amateur photographer when using a battery operated flash system, however, has been failure of the lamp to fire due to weak batteries and/or dirt or corrosion on one or more of the. electrical contacts in the system. To overcome this problem and provide improved flashlamp reliability, percussive-type flashlamps have been developed which may be mechanically fired withminating materialon a wire supported in the tube. Operation of the percussive flashlamp is initiated by an impact onto the tube to cause deflagration of the fulminating material up through the tube to ignite the combustible disposed in the lamp envelope. The percussivetype lamps are also produced in subminiature envelope sizes and are employed in percussive flashcube units having respective preenergized striker springs associated with each lamp, as described in US. Pat. No. 3,597,604. The percussive flashcube is indexed into firing position similarly to the electrical flashcube; however, the flashlamp to be used is fired by the action of a member, associated with the camera shutter mechanism, moving up through the flashcube base to release the respective preenergized striker spring, whereby it sharply impacts against the primer tube of the lamp.

Another development in the field of multilamp flash units for providing additional convenience and flexibility is the provision of a linear or planar array of flashlamps. In such an arrangement, a plurality of lamps face in the direction of the object being photographed whereby it is possible to rapidly switch from one lamp to another or to flash more than one lamp at a time if additional light'is required. Examples of previously described flashlamp arrays are provided by the following US. Pat. Nos.: 3,267,272; 3,430,545; 3,438,315; 3,454,756; 3,458,270; 3,473,880; 3,500,732; 3,544,251; 3,545,904; 3,443,875; 3,552,996; 3,562,508; 3,598,984; 3,598,985; 3,608,451; and 3,614,112.

All of these patents describe electrically energized flash systems with the sequence of lamp flashing being controlled by various electrical switching means including: manually controlled spring slide contacts; a rotary switch; thermally or chemically reactive switches placed in thermal proximity to the flashlamps; a switch within each lamp envelope which closes in response to firing to prepare the next lamp-in sequence; a voltage surge across the lamps causes ignition of only the lamp having the lowest voltage break down characteristics; bimetallic switches; a meltable junction within each lamp envelope; a solid state switching circuits. Although providing a number of advantages, the electrical arrays are still prone to the reliability problems associated with an electrical flash system, namely, ignition failures due to weak batteries and/or corroded electrical contacts.

Another disadvantage of electrical arrays is the rela tive difficulty of maintaining the proper lamp firing sequence in the event the array is removed from a camera and subsequently replaced. To overcome this problem, the prior art, as indicated above, employs special type flashlamps or relatively complex memory circuits or switches in the camera. Such approaches are generally considered undesirable with regard to both cost and reliability.

To overcome the above described disadvantages of electrical arrays,. a copending application Ser. No. 260,286, filed June 6, 1972 and assigned to the present assignee, describes a planar photoflash lamp array including a plurality of percussively-ignitable flashlamps arranged in parallel rows on a support member, along with respectively associated reflectors and preenergized striker springs. The array further includes a selective actuating mechanism comprising a coplanar train of intermeshing spur gears having a number of circumferentially spaced projecting ramps. The gears are supported on shafts having end surfaces upon which the percussive lamps and associated strikers are mounted, and the strikers are radially disposed over the gear and lie in the path of travel of the projecting ramps. Upon the gear train is indexed by a camera energized actuat ing member which successively pushes against pins on the periphery of one of the gears.

SUMMARY OF THE INVENTION Operation of the percussive array described in the aforementioned copending .application is dependent upon adequate stored energy in the, camera mechanism for rotationally indexing the gear train. In many applications, however, it is desirable to substantially reduce or virtually eliminate the power required from the camera mechanism to cause indexing of the movable mem- 1 her in the percussive array.

Accordingly, it is an object of the present invention to provide a self-energized actuating mechanism for a percussive photoflash lamp array.

A further object of the invention is to provide a percam follower inhibits indexing of the spring-loaded movable member and locks the position of the gear train. Upon actuation, a predetermined change in the position of the cam follower momentarily releases the.

spring-loaded movable member to permit indexing of the gear train until the cam follower reaches another quiescent positionon the cam surface. The gear train is then operative. upon successive indexing to sequentially release the preenergized strikers in the array by means of projecting means on the gears to thereby fire respective flashlamps of the array.

In one embodiment, the secondary movable member comprises a spring-loaded rack gear having a sawtooth slot cam in one of its sides. The slot cam is engaged by a pinprojecting from a pivoted arm which may be actuated to control indexing of the rack gear and the springreleasing gear train engaged therewith.

BRIEF DESCRIPTION OF THE DRAWINGS This invention will be more fully described hereinafter in conjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of the exterior of a' multilamp photoflash assembly including features of the invention;

FIG. 2 is a plan view on an enlarged scale of the rear wall of the flash. assembly of FIG. 1 with a selfenergized gear actuating mechanism according to the invention and several striker spring members shown in full and the several flashlamps associated therewith shown in phantom; the view also includes a sectional representation of the base member to show the aperture therethrough;

FIG. 3 is a side view onan enlarged scale of the flash assembly of FIG. 1 with the side wall removed;

FIG. 4 is a fragmentary view of an enlarged scale of a single lamp-firing spring assembly;

4 FIG. 5 is an enlarged-scale detail view of the springloadedrack gear and pivoted arm cam control arrangement in the actuating mechanism of FIG. 2;

FIG. 6 is a fragmentary top view in enlarged detail of the rack gear and pivoted arm of FIGS. 2 and 5; and,

FIG. 7 is an enlarged fragmentary sectional view on line 77 of FIG. 2.

DESCRIPTION OF PREFERRED EMBODIMENT In tlie specific embodiment illustrated in FIGS. 1-3, the photoflash assembly comprises a group of eight axially disposed flashlamps 10 and associated coaxial reflectors 12 arranged in a compact planar array comprising two stacked rows of four lamps each. The array is housed in a box-like container 14 comprising a substantially planar base member 16, a substantially planar support member 18 secured to the rear of base 16 and disposed substantially normal thereto, a pair of

side walls

20 and 22, and a top wall 24. Members 16-24 may comprise a unitary structure of molded plastic, or support member 18 may be separately attached. Enclosure is completed by a sheet of transparent plastic material 26 attached as a front wall to container 14 and disposed over the light emitting side of the array.

Referring to FIGS. 2 and 3, the flashlamps 10 are mounted on one side of the support member 18 with the longitudinal axes of the lamps disposed normal thereto. Also mounted on support member 18 are eight preenergized striker springs 28 each positioned in operative relationship with respect to one of the lamps. As will be described in detail hereinafter, the striker springs are individually releasable to fire the respectively associated lamps.

As best shown in FIG. 2, the selective actuating mechanism according to the invention comprises a coplanar train of two intermeshing spur gears 30 and 32 each having a number of circumferentially spaced projecting ramps 34. The gears are rotatably mounted on a pair of

shafts

36 and 38 fixedly secured at one end to the support member 18. Preferably the shafts comprise integral molded portions of the support member 18. The free-end of each shaft has a substantially planar surface parallel to the plane of the gear mounted thereon, and the gear train is arranged parallel to support member 18. To enable the desired coaction between the gear mechanism and the lamp firing springs,

a cluster of four lamps 10 and four striker springs 28 are symmetrically disposed on the end surface of each shaft so as to provide an overall eight lamp array consisting of two parallel rows of four equally spaced lamps.

Referring to FIGS. 1 and 3, each concave reflector 12 is disposed coaxially about its associated tubular shaped lamp 10,- with all reflectors oriented to face in one direction away from the lamp mounting surface. Each reflector is essentially parabolic but modified by the provision of four flats 39 along the sides thereof. Adjacent flats of adjacent reflectors abut one another to define a compact planar array of reflectors. As may be noted from FIGS. 2 and 3 the hairpin torsional sections of the group of four springs 28 on each shaft are clustered in the central space provided behind each square group of four reflectors.

The array of eight reflectors 12 may comprise a single preformed sheet 40 of plastic material having a light reflective coating; for example, the inwardly dished reflector surfaces 12 may be provided by vacuum forming. Toward the vertex of each reflector is provided a coaxial aperture 41 of suitable shape for fitting about the tubular flashlamp 10. If the radiation from a flashed lamp proves to be a problem by causing sympathetic application.

I As shown particularly in FIG. 4, each lamp comprises an hermetically sealed light-transmitting envelope 42 of tubular shape having a primer 44 depending therefrom. A filling of combustible foil 43, such as zirconium, and a combustion-supporting gas, such as oxygen, are disposed in the envelope. The primer comprises a metal tube 44 coaxially projecting from the envelope and within which a wire anvil and a charge of fulminating material are disposed. Each lamp is supported on the support. member 18 to project normal therefrom and thusaxially parallel to base 16, by means of a respective bore 46 into which the primer tube 44 is inserted. That is, there are four bores 46 in each of the shaft end surfaces, as shown in FIG. 2.

Each preenergized striker spring comprises a folded torsion device typically formed from 0.021 inch music wire about 2.5 inches long. The wire is shaped to form a hairpin torsional section having segments 47 and 48 .joined by a bight 50. The end portion of segment 47 is shaped to define a stationary supporting foot 52, the tip of which is shaped todefme a catch 54. Portions of foot 52 and catch 54 are hidden in FIG. 4. The end portion of segment 48 is shaped to define a striker 56, which when the spring is preenergized, or cocked, as shown, crosses over the supporting foot 52 and is restrained by the catch 54. The stationary supporting foot is seated in an elongated slot formed in the circular end surface of the gear shafton or near a diagonal thereof, the slot being sufficiently shallow to permit catch 54 to project from the end surface of the shaft.

Initially the striker 56 may be formed at an angle of about 90 to the stationary supporting foot 52, although the angle through which the striker is rotated to positionit behind catch 54, as shown, may be of any value that does not cause over stressing of the wire. A center post 58 on the end surface of each gear shaft provides a suitable bearing surface for the heel of the strikerduring cocking, and it also aids in preventing accidental displacement of the spring 28 sufficient to free the striker from the catch some time after cocking and before firing is intended.

Selective displacement of each cocked striker 56, to

. release it from catch 54 and thus permit it to strike the respective primer tube 44 and fire the associated lamp 10, is effected by rotationaly indexing of the gear train. More specifically, as illustrated in FIG. 2, the firing springs 28 on each shaft are arranged with the strikers 56 disposed in a symmetrically radial pattern and projecting beyond the periphery of the circular end surface to overlie a portion of the gear mounted on that shaft. In particular, the free ends of the strikers 56 are disposed to lie in,the path of travel of the ramps 34, which project from each gear. Hence, upon rotationally indexing the gear train, the striker adjacent to an oncoming ramp 34, as shown in FIG. 4, is pushed upwardly by the ramp a distance sufficient to clear the top of the catch 54.- The striker then swings clockwise, as indicated by the arrow, and hits and indents the impact sensitive primer tube 44 at a high velocity to cause deflagration of the fulminating material located therein and thus ignite the combustible foil 43.

Rotational indexing is initiated by external means, but the external energy requirement is minimized, in accordance with the invention, by self-energizing the photo-flash assembly actuating mechanism in the following manner. As illustrated in FIGS. 2 and 3, and in the detail views of FIGS. 7, the mechanism further includes a rack gear 60 slidably mounted in a channel 62 (FIGS. 6 and 7) in either base 16 or a projecting portion of support member 118 so as to engage spur gear 30 by intermeshing of the respective teeth thereof.

The rack' gear 60 may be held in the channel by means of flanges 63 (FIG. 7) which project at right angles from the bottom of the rack and engage grooves 65 along the lower portions of the sidewalls of channel 62. A compression coil spring 64 (FIG. 7, and dashed lines in FIGS. 2 and 5) is inserted part way through the center of rack gear 60 and connected (e.g. by spring pressure) between an internal portion of the rack gear and the left end of support member 18 (or wall 20) to provide sufficient spring loading for urging the rack gear to translate along channel 62 from left to right. Accordingly, spring 64 provides the energy for rotating the

gear train

30, 32 pursuant to translation of rack gear 60.

Indexing of the rack gear, and consequently the spur gear train, is controlled by a spring loaded cam follower which engages a cam surface comprising a sawtooth slot 66 located on one side of the rack gear. More specifically, the cam follower comprises a pin 68 attached to the left end of a pivoted arm 70 monted on base 16 or a projecting portion of support member 18. For example, the right end of arm 70 may be secured by a pivot pin 72 to an upstanding support 74.

Each sawtooth of the slot cam 66 has a vertical portion 76 and a ramp portion 78 (FIG. 5). Normally, the pin 68 engaging slot 66 assumes a quiescent position at the bottom of vertical portion 76, as shown in FIG. 5. In this quiescent position, pin 68 inhibits indexing of the rack gear and thereby locks the position of the spur gears 30 and 32. Preferably, the pivoted arm 70 is loaded by a spring 30 to urge pin 68 toward the bottom of the vertical slot portion 76, thereby insuring that the gear train is not unintentionally released by mechanically induced shock during handling and shipping.

In the embodiment illustrated, the pivoted arm contains a flat tab 82 which is rendered accessible to external actuating means through an aperture 84 provided in base member 16. For example, gear indexing may be effected by a suitable actuating member 86 moving up through aperture 84 to engage and push against the tab 82 of the spring loaded arm 70. The upward movement of member 86 causes pin 68 to traverse the vertical portion 76 until it clears the top of the vertical face of the slot cam and is thereby placed in movable engagement with the ramp portion 78. This action releases the rack gear 60 to permit the loading spring 64 to push the sliding rack to the right and thereby rotate gear 30 counterclockwise, which in turn rotates gear 32'clockwise. The movement of the rack 60 forces pin 68 to travel down the ramp portion 78 of the slot cam until it contacts the next vertical face and thereby stops the sliding rack and prevents further rack travel. Hence the gear rotation is a momentary indexing movement, as the angular displacement is terminated when the travel of pin 68 reaches the next quiescent position on the slot cam at the bottom of a vertical portion 76. The angular displacement resulting from the aforementioned operation is determined by the pitch of the sawtooth slot and, in the illustrated embodiment, is operative to cause one lamp to be fired. In a typical application, actuating member 86 may be part of a camera mechanism designed to enable the photographer to flash a lamp in synchronization with the tripping of the camera shutter to take a picture. The camera machanism should be designed so that it senses downward travel of the pin 68 and arm 70 assembly and thereupon disconnects the camera source of motive power to permit the spring loaded arm and pin to lock the position of the gear train and prevent release of a second spring.

After the last lamp has been flashed, pin 68 slides into a straight slot 88, whereupon tab 82 is in a high position so that the camera can sense that the array is expended.

In the present flash unit, eight lamps are available to be sequentially flashed in response to successive indexing of the gear train by the pivoted arm and camcontrolled rack. Thus, for example, eight rapid flash exposures may be taken with a camera, without the need for moving the lamps or rotating the unit. The sequence of releasing the strikers in response to indexing is programmed by the number and circumferential location of the ramps 34 on each gear. That is, the ramps 34 are arranged so that for a selected increment x of rotational displacement, the gear travel will cause a first ramp in the train to release a striker and a second ramp in the train to be moved to a position adjacent another preenergized striker 56, as shown in FIG. 4. This pattern of ramp positioning then continues for all successive 1: increments of rotation until all springs have been released. Typically, each indexing cycle will produce an x increment of gear rotation to provide a single lamp ignition.

As described above, the new position of the gear train is retained after each indexing cycle by means of the spring loaded arm 70, which returns pin 68 to engage the next vertical cam slot on rack gear- 60. Hence, by virtue of the mechanical firing system, the rampprogramming, and the cam-controlled rack, the present photoflash assembly provides a self-contained memory function, whereby the next unused lamp in the flash sequence will always be ready for immediate triggering,

even through the unit may have been removed from the camera and subsequently replaced. This is a significant advantage as compared to electrical arrays.

Most importantly, however, substantially all of the power required to rotate the spur gears 30, 32 and release all eight springs is provided by the rack loading spring 64. The only power required from the camera would be the small amount required to push the pivoted arm 70 upward'untilfpin 68 clears the vertical stop face. Hence, a self-energized, percussive flashlamp array is provided which substantially reduces the camera power requirements for flash actuation.

In one embodiment of this invention, as illustrated in FIG. 2, a pair of spur gears 30 and 32 each having 32 teeth and a diameter of one inch are mounted on a sup port member 18. Two ramps 34 are provided on each gear thereby requiring 180 total rotation to release the eight striker springs. Each of the ramps 34 comprises a projection sloped on two opposite sides so that the same standard gear design can be used for both clockwise and counterclockwise gear rotation. The gears are retained on

shafts

36 and 38 by the overlying strikers 56; hence, the ramps 34 are located radially outward from the inside edge of each gear to provide clearance for striker overhang after the spring is released so that the gears will continue to be held in position but free to rotate. The center to center circumferential spacing of the ramps is 135 (12 teeth), and the starting position of the gears is as shown in FIG. 2.

The bottom of the base 16 may be provided with suitable means for mounting the photoflash assembly on apparatus such as a camera. For example, as shown in FIGS 2 and 3, a mounting post 90 may be provided which is shaped to mate with the socket ona camera of the type generally available for use with percussive flashcubes, such as that described in US. Pat. 3,602,618, for example. In such cases, either the camera would be modified to render the socket nonrotating, or the post 90 would be allowed to rotate while the base remains stationary. The latter design approach would make the array adaptable for use on a camera which is also usable with rotating fiashcubes. in addition, the camera would be modified to remove the upward sensing portion of the operation (for detecting released strikers), or spring 80 would be made sufficiently strong to prevent arm from releasing the rack during the upward sensing movement of actuating member 86. Also, as mentioned hereinbefore, the Camera should be modified to sense downward travel of the pin 68 and arm 70 assembly, and in response thereto, retract member 86 to prevent'unintentional spring release.

Although the invention has been described with respect to specific embodiments, it will be appreciated that modifications and changes may be made by those skilled in the art without departing from the true spirit and scope of the invention. For example, the number of lamps in the array may be varied, with a corresponding variation in the number of gears. Also, the number and spacing of the ramps 34 mayvary, The gears can be arranged in various ways, yielding vertical, square, rectangular, T-, or L-shaped gear train configurations. Means other than ramps may be employed for selectively releasing the strikers. The slot cam may be located on the bottom or opposite side of the rack. The lever arm and pin may be located differently. An extension coil spring connected between the rack and the I right end of the support member may be used for loading the sliding rack gear in lieu of the described compression spring. Further the rack may engage pins rather than gear teeth to transmit linear to rotational motion.

What I claim is:

l. A self-energized selective actuating mechanism for a photoflash lamp array; said array including a support member, a plurality of percussively-ignitable flashlamps mountedon said support member, and a plurality of preenergized strikers mounted on said support memberand releasable to tire said flashlamps; the selective actuating mechanism comprising:

a first movable member;

means supporting said first movable member in operative alignment with respect to said strikers;

means projecting from said first movable member and adapted for selectively releasing said preenergized strikers;

a second movable member engaged with said first movable member and having a cam surface thereon;

means for spring loading said second movable member sufficiently to cause indexing thereof and thereby indexing of said first movable member engaged thereto; and,

a cam follower engaging the cam suface on said second movable member, said cam surface being shaped whereby the quiescent position of said cam follower inhibits indexing of said second movable member and a predetermined change in position of said cam follower momentarily releases said springloaded second movable member to permit indexing of said second and first movable members until said cam follower reaches another quiescent position on said cam surface;

said first movable member being operative upon successive indexing to sequentially release said strikers by means of said projecting means to fire respective flashlamps of said array.

2. The mechanism of claim 1 further including means for spring loading said cam follower.

3. The mechanism of claim 1 wherein said cam follower comprises a pin attached to a pivoted arm supported in operative relationship to said second movable member and operative upon actuation to cause release of said spring-loaded second movablemember to permit indexing of said second and first movable members by an amount determined by the shape of said cam surface engaged by said pin.

4. The mechanism of claim 3 further including means for spring loading said pivoted arm.

5. The mechanism of claim 1 wherein said cam surface comprises a sawtooth slot in said second mova'ble member, said slot having a vertical portion and a ramp portion, the quiescent position of said cam follower being in the vertical portion of said sawtooth slot, and said second movable member being released for indexing when the position of said cam follower is changed to permit it to movably engage the ramp portion of said sawtooth slot.

6. The mechanism of claim 5 wherein said cam follower comprises a pin attached to a spring-loaded, pivoted arm supported in operative relationship to said second movable member and operative upon actuation to cause said pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot, thereby releasing said springloaded second movable member to permit indexing of said second and first movable members by an amount determined by the pitch of said sawtooth slot.

7. The mechanism of claim 1 wherein said first movable member comprises a spur gear, said supporting means comprises a portion of said support member shaped to provide a stationary shaft upon which said spur gear is rotatably mounted, said shaft having a free end with a substantially planar surface parallel to the plane of said spur gear, said flashlamps and strikers are mounted on said planar surface at the free end of said shaft with said preenergized strikers being disposed radially thereon, and said second movable member comprises a rack gear slidably mounted in operative relationship to said spur gear.

8. The mechanism of claim 7 wherein said spring loading means comprises a compression coil spring connected between said support member and said slidable rack gear for urging said rack gear into translation.

9. The mechanism of claim 7 wherein said rack gear is engaged with said spur gear by intermeshing of the respective teeth thereof.

10. The mechanism of claim 7 wherein said cam surface comprises a sawtooth slot in a side of said rack gear, said slot having a vertical portion and a ramp portion, and said cam follower comprises a pin attached to a pivoted arm supported in operative relationship to said rack gear, the quiescent position of said pin being in the vertical portion of said sawtooth slot, and said pivoted arm being operative upon actuation to cause said-pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot, whereby said spring-loaded rack gear is released to permit translation thereof, and consequently rotational indexing of said spur gear, by an amount determined by the pitch of said sawtooth slot.

11. The mechanism of claim 10 further including means for spring loading said pivoted arm.

12. A photoflash assembly comprising, in combination:

a'substantially planar support member;

a plurality of shafts fixedly secured at one end to said support member;

a coplanar train of intermeshing spur gears rotatably mounted on said shafts, each of said gears on a respective one of said shafts, with said gear train lying in a plane parallel to said support member;

the free end of each of said shafts having a substantially planar surface parallel to the plane of the gear mounted thereon and the plane of said support member;

a plurality of percussively-ignitable flashlamps mounted on the planar surface of each of said shafts with the longitudinal axes of said lamps disposed normal to said planar surface;

a plurality of preenergized strikers radially mounted on the planar surface of each of said shafts and individually releasable to fire a respective one of said flashlamps;

means projecting from said gears and adapted for selectively releasing said preenergized strikers;

a movable member mounted on said support member and engaged with one of said gears, said movable member having a cam surface thereon;

means for spring loading said movable member sufficiently to cause indexing thereof and thereby indexing of said gear train; and,

a cam follower connected to said support member and engaging the cam surface of said movable member, said cam surface being shaped whereby the quiescent position of said cam follower inhibits indexing of said movable member and a predetermined change in position of said cam follower momentarily releases said spring-loaded movable member to permit indexing of said movable member and said gear train until said cam follower reaches another quiescent position on said cam surface;

said gear train being operative in response to successive indexing to sequentially release said strikers by means of said projecting means to fire respective flashlamps of said array.

13. The mechanism of claim 12 wherein said movable member comprises a rack gear slidably mounted on said support member, and said cam surface comprises a sawtooth slot in a side of said rack gear, said slot having a vertical portion and a ramp portion, the quiescent portion of said cam follower being in thevertical portion of said sawtooth slot, and said slidable rack gear being released for indexing when the position of said cam follower is changed to permit it to movably engage the ramp portion of said sawtooth slot.

lower comprises a pin attached to a pivoted arm mounted on said support member, said pivoted arm being accessible to be actuated for causing said pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot,

whereby said spring-loaded rack gear is released to permit translation thereof, and consequently indexing of said gear train, by an amount determined by the pitch of said sawtooth slot.

17. The mechanism of claim 16 further including means for spring loading said pivoted arm.

18. The assembly of claim 16 wherein the radially mounted strikers of each shaft project beyond the periphery of the planar surface thereof to overlie a portion of the spur gear mounted thereon, and said means projecting from said spur gears comprises oneor more ramps on each of said spur gears, said sequence of releasing said strikers being programmed by the number and circumferential location of said ramps on each gear.

Claims

1. A self-energized selective actuating mechanism for a photoflash lamp array; said array including a support member, a plurality of percussively-ignitable flashlamps mounted on said support member, and a plurality of preenergized strikers mounted on said support member and releasable to fire said flashlamps; the selective actuating mechanism comprising: a first movable member; means supporting said first movable member in operative alignment with respect to said strikers; means projecting from said first movable member and adapted for selectively releasing said preenergized strikers; a second movable member engaged with said first movable member and having a cam surface thereon; means for spring loading said second movable member sufficiently to cause indexing thereof and thereby indexing of said first movable member engaged thereto; and, a cam follower engaging the cam suface on said second movable member, said cam surface being shaped whereby the quiescent position of said cam follower inhibits indexing of said second movable member and a predetermined change in position of said cam follower momentarily releases said spring-loaded second movable member to permit indexing of said second and first movable members until said cam follower reaches another quiescent position on said cam surface; said first movable member being operative upon successive indexing to sequentially release said strikers by means of said projecting means to fire respective flashlamps of said array.

3. The mechanism of claim 1 wherein said cam follower comprises a pin attached to a pivoted arm supported in operative relationship to said second movable member and operative upon actuation to cause release of said spring-loaded second movable member to permit indexing of said second and first movable members by an amount determined by the shape of said cam surface engaged by said pin.

5. The mechanism of claim 1 wherein said cam surface comprises a sawtooth slot in said second movable member, said slot having a vertical portion and a ramp portion, the quiescent position of said cam follower being in the vertical portion of said sawtooth slot, and said second movable member being released for indexing when the position of said cam follower is changed to permit it to movably engage the ramp portion of said sawtooth slot.

6. The mechanism of claim 5 wherein said cam follower comprises a pin attached to a spring-loaded, pivoted arm supported in operative relationship to said second movable member and operative upon actuation to cause said pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot, thereby releasing said spring-loaded second movable member to permit indexing of said second and first movable members by an amount determined by the pitch of said sawtooth slot.

10. The mechanism of claim 7 wherein said cam surface comprises a sawtooth slot in a side of said rack gear, said slot having a vertical portion and a ramp portion, and said cam follower comprises a pin attached to a pivoted arm supported in operative relationship to said rack gear, the quiescent position of said pin being in the vertical portion of said sawtooth slot, and said pivoted arm being operative upon actuation to cause said pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot, whereby said spring-loaded rack gear is released to permit translation thereof, and consequently rotational indexing of said spur gear, by an amount determined by the pitch of said sawtooth slot.

12. A photoflash assembly comprising, in combination: a substantially planar support member; a plurality of shafts fixedly secured at one end to said support member; a coplanar train of intermeshing spur gears rotatably mounted on said shafts, each of said gears on a respective one of said shafts, with said gear train lying in a plane parallel to said support member; the free end of each of said shafts having a substantially planar surface parallel to the plane of the gear mounted thereon and the plane of said support member; a plurality of percussively-ignitable flashlamps mounted on the planar surface of each of said shafts with the longitudinal axes of said lamps disposed normal to said planar surface; a plurality of preenergized strikers radially mounted on the planar surface of each of said shafts and individually releasable to fire a respective one of said flashlamps; means projecting from said gears and adapted for selectively releasing said preenergized strikers; a movable member mounted on said support member and engaged with one of said gears, said movable member having a cam surface thereon; means for spring loading said movable member sufficiently to cause indexing thereof and thereby indexing of said gear train; and, a cam follower connected to said support member and engaging the cam surface of said movable member, said cam surface being shaped whereby the quiescent position of said cam follower inhibits indexing of said movable member and a predetermined change in position of said cam follower momentarily releases said spring-loaded movable member to permit indexing of said movable member and said gear train until said cam follower reaches another quiescent position on said cam surface; said gear train being operative in response to successive indexing to sequentially release said strikers by means of said projecting means to fire respective flashlamps of said array.

13. The mechanism of claim 12 wherein said movable member comprises a rack gear slidably mounted on said support member, and said cam surface comprises a sawtooth slot in a side of said rack gear, said slot having a vertical portion and a ramp portion, the quiescenT portion of said cam follower being in the vertical portion of said sawtooth slot, and said slidable rack gear being released for indexing when the position of said cam follower is changed to permit it to movably engage the ramp portion of said sawtooth slot.

14. The mechanism of claim 13 wherein said spring loading means comprises a compression coil spring connected between said support member and said slidable rack gear for urging said rack gear into translation.

15. The mechanism of claim 13 wherein said rack gear is engaged with one of said spur gears by intermeshing of the respective teeth thereof.

16. The mechanism of claim 13 wherein said cam follower comprises a pin attached to a pivoted arm mounted on said support member, said pivoted arm being accessible to be actuated for causing said pin to traverse the vertical portion of said sawtooth slot into movable engagement with the ramp portion of said slot, whereby said spring-loaded rack gear is released to permit translation thereof, and consequently indexing of said gear train, by an amount determined by the pitch of said sawtooth slot.

18. The assembly of claim 16 wherein the radially mounted strikers of each shaft project beyond the periphery of the planar surface thereof to overlie a portion of the spur gear mounted thereon, and said means projecting from said spur gears comprises one or more ramps on each of said spur gears, said sequence of releasing said strikers being programmed by the number and circumferential location of said ramps on each gear.