US3812339A

US3812339A - Selective actuating mechanism for percussive photoflash lamp array

Info

Publication number: US3812339A
Authority: US
Inventors: D Broadt
Original assignee: GTE Sylvania Inc
Current assignee: GTE Sylvania Inc
Priority date: 1973-01-02
Filing date: 1973-01-02
Publication date: 1974-05-21
Anticipated expiration: 1991-05-21
Also published as: JPS4999027A; JPS5635851B2; DE2364871A1; CA999838A

Abstract

LATCH ENGAGING ONE OF A PLURALITY OF EVENLY SPACED PINS ON THE GEARS. TO FLASH A LAMP, THE LATCH IS MOMENTARILY RELEASED TO PERMIT ROTATIONAL INDEXING OF THE GEARS, WHEREUPON ONE OF THE RAMPS RELEASES A STRIKER. IN ANOTHER EMBODIMENT, A SPRING LOADED SLIDABLE BAR WITH RAMPS IS LINEARLY INDEXED IN A SIMILAR MANNER.

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. IN ONE EMBODIMENT, THE SELFENERGIZED ACTUATING MECHANISM COMPRISES 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. THE GEARS ARE SPRING LOADED TO ROTATE WHEN NOT LOCKED IN PLACE BY A

Description

United States Patent Broadt [451 M22251??? SELECTIVE ACTUATING MECHANISM FOR PERCUSSIVE PHOTOFLASI-I LAMP 57 ABSTRACT ARRAY 0 For a photoflash assembly comprising a plurality of Inventor: David Lewlsburg, percussively-ignitable flashlamps arranged in an array [73] Assignee: GTE sylvania Incorporated, with respectively associated reflectors and preener- Danvers Mass gized striker springs, a self-energized selective actuating mechanism for sequentially releasing the striker Filedi J n- 1973 springs to fire respective flashlamps in response to 211 Appl. No.: 320,008

Primary Examiner-Fred L. Braun Att0rney,'Agent, or FirmNorman .I. OMalley et al.

successive indexing. In one embodiment, the selfenergized actuating mechanism comprises 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 thesurrounding gear to lie in the path of travel of the ramps. The gears are spring loaded to rotate when not locked in place by a latch engaging one of a plurality'of evenly spaced pins on the gears. To flash a lamp, the latch is momentarily released to permit rotational indexing of the gears,-

whereupon one of the ramps releases a striker. In another embodiment, a spring loaded slidable bar with ramps is linearly indexed in a similar manner.

20 Claims, 13 Drawing Figures ea 1 .21 61 T1 66 1o 38 19 i 17 ao. I9 -/4e I .-1e 4s 1s as as 5 x 2 w 10 o 0 Z: 53 I K? 4% 74 SELECTIVE ACTUATING MECHANISM FOR PERCUSSIVE PHOTOFLASH LAMP ARRAY BACKGROUND OF THE INVENTION This invention relates to multilamp photoflash units and, more particularly, to an array of percussivelyignitable photoflash lamps with self-energized means for selectively controlling the firing thereof.

The trend in photoflash devices has been toward the use of subminiature flashlamps (an envelope volume of less than 1 cubic centimeter) in compact, disposable, multilamp units to provide camera users with the advantages of greater convenience, compactness and portability. A currently popular flash lamp unit of this type is known generally in the trade as a flashcube, a specific embodiment of which is shown in U.S. 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 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 afilament 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.

out the need for batteries. As described in U.S. Pat. No.

3,535,063, for example, such flashlamps have a mechanical primer sealed in one end of the lamp in lieu of lead-in wires. This primer may comprise a metal tube extending from the lamp envelope and a charge of fulminating material on a wire supported on 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 U.S. 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 onelamp at a time if additional light is required. Examples of previously described flashlamp arrays are provided by the following U.S. 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; 3,562,508; 3,598,984; 3,598,985; 3,608,451; and 3,614,412.

All of these patents describe electrically energized flash systems with the sequence of lamp flashing being controlled by various electrical I 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; and solid state switching circuits. Although providing a number of advantages, the electri cal arrays are still prone to the reliability problems associated with an electrical flash system, namely, ignition failures due to weak batteries and/or dirty or corroded electrical contacts.

Another disadvantage of electrical arrays-is the relative 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 pe'rcussively-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 rotationally indexing the gear train, the ramps selectively release the strikers, with the sequence of striker release being programmed by the member and circumferential location of the ramps. For use with a camera, the gear train is indexed by a camera energized actuating member which successively pushes against pins on the periphery of one of the gears.-

Another type of percussive lamp array is described in a-copending application Ser. No. 261,588, filed June 12, 1972 and assigned to the present assignee. In this case a linear photoflash lamp array is provided by mounting the lamps, strikers and reflectors in a row and using a selective actuating mechanism comprising a slidable bar retained in a longitudinal channel which is parallel to the row of flashlamps and strikers. The slidable bar is provided with a number of linearly spaced projecting ramps, and the strikers are mounted to project beyond the periphery of the channel to lie in the path of travel of the ramps. Linear indexing of the slidable bar along the channel causes one of the ramps to release a preenergized striker, and sequential lamp firing is effected by successive indexing of the bar. For use with a camera, the slidable bar is indexed by a camera energized actuating member which successively pushes against ratchet teeth on the bar. A variation of the slidable bar approach for actuating a planar array of percussive flashlamps is described in a copending application Ser. No. 315,812, filed Dec. 18, 1972 and assigned to the'present assignee.

SUMMARY OF THE INVENTION Operation of the percussive arrays described in the aforementioned copening application is dependent upon adequate stored energy in the camera mechanism. 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 member in the percussive array.

I Accordingly, it isan 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 percussive flashlamp array which requires a minimum of external actuating energy for operation.

Briefly, these objects are attained'by spring loading the movable member in the array sufficiently to cause indexing thereof, providing a plurality of evenly spaced index stops on the movable member, and including in the array a releasable latching means which normally engages the index stops to lock the position of the movable member. The latching means is operable for momentarily releasing the spring loaded movable member to permit indexing thereof until the next index stop is engaged. The movable member is then operative upon successive indexing to sequentially release the preenergized strikers in the array by means of projecting means on the movable member to thereby fire respective flashlamps of the array.

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 on an enlarged scale of the flash assembly of FIG. 1 with the side wall removed;

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

FIGS. 5 and 6 are simplified sectional views of one of the gears of FIG. 2 showing the flat spiral spring used for biasing the gear to rotate;

FIG. 7 is a perspective view of the exterior of another multilamp photoflash assembly including features of the invention; I

FIG. 8 is a top plan view of the photoflash assembly of FIG. 7 with a set of self-energized slidable bar actuating mechanism according to the invention and the several striker spring members shown in full and the several flashlamps and reflectors shown in phantom;

FIG. 9 is a sectional elevation on line 9-9 of FIG. 8 which illustrates the position of one of the slidable bars with respect to the associated linear array of lamps and strikers, the spring loading and latch mechanism according to the invention, and the aperture through which said bar may be indexed;

FIG. 10 is a fragmentary sectional view on line 10-10 of FIG. 8 which is somewhat enlarged and simplified to more clearly shown one of the spring members and its position with respect to the self-energized I slidable bar;

DESCRIPTION OF PREFERRED EMBODIMENT In the 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 frontwall to container 24 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 a respective 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 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 freeend 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 and four striker springs 28 are symmetrically disposedon the end surface of each gear 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 section 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 ignition of an unselected lamp, the parabolicreflector skirt 12 may be extended back to cover substantially the entire lamp envelope, rather than leaving an exposed portion as illustrated in FIG. 3. The overall package configuration of a similar lamp-reflector array is the subject of a copending application Ser. No. 260,271, filed June 6, 1972 and assigned to the assignee of the present application.

As shown particularly in FIG. 4, each lamp 10 comprises an hermetically sealed light-transmitting envelope 42 of tubular shape having a primer 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 thus axially 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 to define a catch 54. Portions of foot 52 and catch 54 are hidded 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 elonated slot formed in the circular end surface of the gear shaft on 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 position it 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 striker during 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 be fore 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 rotational 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 thatshaft. In particular, the free end 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 photoflash assembly actuating mechanism in the following manner. As illustrated in FIGS. 5 and 6, a flat spiral spring 60 is mounted on shaft 36 (and/or 38) and connected to the gear 30 (or 32) on that shaft to provide sufficient spring loading for urging the gear to rotate about its shaft. Indexing of the gears is controlled by engagement and release of index stops comprising a plurality of circumferentially spaced pins on each of the gears. More specifically, to enable indexing of this gear train in eight equal increments, eight evenly spaced pins 61-68 are provided along the periphery of gear 30 and eight evenly spaced pins 71-78 are provided along the periphery of gear 32, as indicated in FIG. 2. Each of the pins project normal to the plane of the gear as illustrated in FIG. 3.

To lock the position of the spring loaded gears, a releasable latching means engages one of these index pins. As shown in FIG. 2, this latching means may comprise a lever mounted on support member 18 by a centrally disposed fulcrum means, such as a pin 82. Lever 80 has

protrusions

84 and 86 at each end for alternately engaging the index pins on the two adjacent gears, and it is spring loaded by a spring 88 mounted on base 16 to normally assume the substantially horizontal position shown in FIG. 2. In this normal, or locked, position, protrusion 86 of the lever engages one of the index pins of gear 32.

In the embodiment of FIG. 2, the spring loading is applied to the lever arm under protrusion 86, and the lever arm under protrusion 84 is rendered accessible to external actuating means through an aperture 90 provided in base member 16. For example, gear indexing may be effected by a suitable actuating member 92 moving up through aperture 90 to engage and push against the lever arm under protrusion 84. The upward movement of member 92 causes lever 80 to move up on the left side and down on the right side, thereby disengaging protrusion 86 from index pin 71 on gear 32 and permitting the spring loaded gear train to rotate, gear 32 clockwise and gear 30 counterclockwise. The gear rotationis a momentary indexing movement, as the angular displacement is terminated when the raised lever protrusion 84 engages pin 61 of rotating gear 30. When member 92 is thereafter retracted, the spring loaded lever 90 returns to its horizontal position, with protrusion 84 movingdownward to snap out of engagement with pin 61 of gear 30 and protrusion 86 moving upward to snap into engagement with index pin 72 of gear 32, and thereby again lock the position of the gear train. The angular displacement resulting from the aforementioned operation is determined by the circumferential spacing between the index pins on a gear and, in the illustrated embodiment, is operative to cause one lamp to be fired. In a typical application, actuating member 92 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.

- In the present flash unit, eight lamps are avaiable to be sequentially flashed in response to successive indexing of the gear train by member 92. Thus, for example, eight rapid flash exposures may be taken with a camera, withoutthe 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, theramp's 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 secondramp in the train to be moved to a position adjacent another preenergized striker 56, as shown in F IG. 4. This pattern of ramp positioning then continues for all successive x increments of rotation until all springs havebeen released. Typically, each indexing cycle will produce an x increment of gear rotation to provide a single lamp ignition.

The new position of the gear train is retained after each indexing cycle by means of the spring loaded lever 80, which returns protrusion 86 to engage the next pin on gear 32. Hence, by virtue of the mechanical firing system, the ramp programming, and the spring lever control, 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 though the unit may have been removed from a camera and subsequently re- I placed. This is a significant advantage as compared to electrical arrays. V

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 support member 18 measuring about 1.5 inches by 2.53 inches. 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. I

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 94 may be provided which is shaped to mate with the socket on a camera of the type generally available for use with percussive flashcubes, such as that described in US. Pat. No. 3,602,618, for example. In such cases, either the'camera would be modified to render the socket nonrotating, or the post 94 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 flashcubes. In addition, the camera would be modified to remove the sensing portion of the operation, or spring 88 would be sufficient to prevent lever from releasing the gears during the sensing movement of actuating member 92.

The self-energizing principle of thepresent invention may also be applied to the slidable bar type actuating mechanisms of the aforementioned copending applications Ser. Nos. 261,588 and 315,8l2. A specific embodiment of a self-energized linear array is illustrated in FIGS. 7-9, wherein a photoflash assembly comprises a substantially planar base, or support member, 112 having eight percussively-ignitable flashlamps 121-128 and eight respectively associated preenergized striker springs 131-138 mounted on its upper sur-' face. The flashlamps are arranged in two parallel rows of four lamps each, and each of the preenergized striker springs is positioned in operative relationship with a respective one of the lamps. As shown in FIG. 8, the flashlamps of row -128 are staggered relative to the flashlamps of row 121-124, and disposed between these two rows of lamps are two arrays and 142 of substantially concave reflectors arranged in a nested back-to-back relationship to face in opposite directions. To complete the unit, the assemblage of lamps, striker springs and reflectorsis enclosed in a transparent cover 144 secured to the base 112.

Each of the lamps 121-128 is substantially identical and comprises (see lamp 121 of FIG. 9) an hermetically sealed light-transmitting envelope 146 having a primer depending therefrom and a filling of combustible foil 148 and a combustion-supporting gas disposed therein. The primer comprises a metal tube 150 within which a wire anvil and a charge of fulminating material are disposed. Each lamp is vertically supported in the base 112 by means of a respective bore 152 (also see FIG. 8) into which the primer tube 150 is inserted.

Each of the preenergized striker springs 131-138 is substantially identical and comprises a folded torsion device typically formed from 0.021 inch music wire about 2.5 inches long. Referring to FIG. 10, and the numerically identified elements of spring 31, the wire is shaped to form a hairpin torsional section having segments 154 and 156 joined by a bight 158. The end portion of segment 154 is shaped to define a stationary supporting foot 160, the tip of which is shaped to define a catch 162. The end portion of segment 156 is shaped to define a striker 164, which when the spring is preenergized, or cocked, as shown, crosses over the supporting foot 160 and is retained by catch 162. The stationary supporting foot 160 is seated in an elongated slot formed in the base 112, the slot being sufficiently shallow so that the catch 162 formed in the free end of foot 160 will project above the upper surface of base 112.

Initially the striker 164 may be formed at an angle of about 90 to the stationary supporting foot 160, although the angle through which the striker is rotated to position it behind catch 162, as shown, may be of any value that does not cause overstressing of the wire. The base 112 is shaped to provide a suitable bearing surface 166 for the heel of foot 160 during cocking. This bearing surface also aids in preventing accidental displacement of the spring sufficiently to free the striker from the catch sometime after cocking and before firing is intended.

Sequential displacement of each cocked striker 164, to release it from the catch 162 and thus permit it to strike the respective primer tube 150 and fire the associated lamp, is effected by a selective actuating mechanism. Referring to FIGS. 8-10, the actuating mechanism for the row of strikers 131-134 comprises a slidable bar 168 having four linearly spaced prjecting ramps 171-178 disposed along one side thereof. The bar 168 is retained in a longitudinal channel 176 in base 112 which is located parallel to the row of lamps 121-124. Each cocked striker 164 of the springs 131-134 projects beyond the periphery of channel 176 to overlie a portion of the slidable bar 168. In particular, the free end of each striker 164 is disposed to lie in the path 'of travel of a respective one of the ramps 171-174 on bar 168. Hence, upon translationally indexing the bar 168 along channel 176, the striker adjacent to an upcoming ramp (such as striker 164 of spring 131 is adjacent to ramp 171) is pushed upwardly by the ramp a distance sufficient to clear the top of catch 162. The striker then swings clockwise, as viewed from above, and hits and indents the impact sensitive primer tube 150 at a high velocity to cause defla gration of the fulminating material located therein and thus ignite the .combustible foil 148.

Bar l68may be retained in channel 176 by the overlying strikers 164, with the location of the ramps providing a clearance for striker overhang after the spring is released so that the bar will continue to be held in position but free to translate. Alternatively, the bar 168 may be held in the channel by means of tabs 178 which project at right angles from the bottom of the bar and engage a groove 180 (FIG. along the lower portion of the sidewall of channel 176.

The preenergi zed striker springs 135-138 associated with lamps 125-128 are mounted in a direction opposite to that of springs 131-134, as indicated in FIG. 8. Hence, base 112 also defines a second longitudinal channel 182 adjacent to the strikers of springs 135-138 and having a periphery beyond which the cocked strikers of the springs project. Channel 182 is parallel to channel 176, and the two rows of flashlamps are parallel with and disposed between these two channels. A second slidable bar 184 having four linearly space ramps 191-194 is retained in channel 182 underlying the adjacent strikers. Bar 184 is adapted to be indexed in a direction opposite to the indexing direction of bar 168 for selectively releasing springs -138 in the same manner as described for the release of springs 131-134 by bar 168. That is, when base 112 is rotated 180, bar 184 will also move from left to right.

Reflector arrays and 142 are substantially identical; each comprises a strip of preformed sheet material having a light reflective coating and defining a set of four inwardly dished, individual light reflector surfaces 186 of suitable shape for fitting about respective ones of the flashlamps. As shown in FIGS. 7 and 8 each reflector of array 140 is disposed behind a respective one of the flashlamps of the row 121-124. Hence, upon ignition of one of the flashlamps 121-124, the surface 186 behind that lamp reflects light in the direction toward which the lamp-reflector unit is facing.

The four reflectors of array 142, on the other hand, are respectively disposed behind the four flashlamps of row 125-128 so as to face in the opposite direction from that of the reflectors of array 140. As illustrated by FIGS. 7 and 8, therefore, the photoflash assembly 110 comprises a symmetrical arrangement of reflectors, lamps, springs and indexable actuating bars for providing two operative flashlamp arrays facing in opposite directions. The hairpin torsional sections of the springs are located behind the reflectors (FIG. 8), with a clearance being provided along the lower edges of the reflectors to permit free operation of the strikers.

In accordance with the invention, self-energized, translational indexing of each slidable bar is provided in the following manner. As illustrated in FIGS. 8-10, an extension coil spring 196 is stretched part way through the center of bar 168 and connected between that bar and the right end of channel 176 to provide sufficient spring loading for urging bar 168 to translate along channel 176 from left to right. In FIG. 9, a portion of bar 168 is broken away to illustrate the internal connection of spring 196. Indexing of theslidable bar is controlled by engagement and release of a plurality linearly spaced index pins on the side of the bar. More specifically, to enable indexing of slidable bar 164 in four equal increments, seven evenly spaced pins 201-207 are provided along the side of the bar, as illustrated in FIGS. 9 and 11. Each of the pins project parallel to the plane of the support member.

To lock the position of the spring loaded bar, a releasable latching means engages one of these pins in a similar manner to that described hereinbefore with respect to the gear train. As shown in FIGS. 9 and 12, this latching means may comprise a lever 2'10 mounted on support member 112 by a centrally disposed fulcrum means, such as a pin 212. Lever 210 has

protrusions

214 and 216 at each end for alternately engaging the first and last of a linear set of four pins, and it is spring loaded by a spring 218 mounted on support member 112 to normally assume-the substantiallyhorizontal position shown in FIGS. 9 and 12. in this normal, or locked, position, protrusion 216 engages one of the index pins of bar 168. Clearance for pins 201-207 and the spring loaded lever 210 is provided by an elongated cavity 220 in support member 112, lever 210 being mounted on the side of the cavity and spring 218 being mounted on the bottom of the cavity.

In the embodiment illustrated, the spring loading is applied to the lever arm under protrusion 216, and the lever arm under protrusion 214 is rendered accessible to external actuating means through an aperture 222 provided in support member 112. For example, bar indexing may be effected by a suitable actuating member 224 moving up through aperture 222 to engage and push against the lever arm under protrusion 214. The upward movement of member 224 causes lever 210 to move up on the left side and down on the right side, thereby disengaging protrusion 216 from index pin 201 and permitting the spring loaded bar 168 to translate along channel 176 from left to right. The bar translation is a momentary indexing moment as the linear displacement is terminated when the raised lever protrusion 214 engages pin 204 of the moving bar. When member 224 is thereafter retracted, the spring loaded lever 210 returns to its horizontal position, with protrusion 214 moving downward to snap out of engagement with pin, 204 and protrusion 216 moving upward to snap into engagement with index pin 202, thereby again locking the position of the bar. The angular displacement resulting from the aforementioned operation is determined by the linear spacing between the index pins on the bar and, in the illustrated embodiment, is operative to cause one lamp to be fired. In a typical application, actuating member 224 may be part of a camera mechanism designed to enable the photographer to flash a lamp in synchronization with the tripping to the camera shutter to take a picture.

The bottom of base 112 may be provided with suitable means for mounting the photoflash assembly 110 on apparatus such as a camera. For example, as shown in FIG. 9, a pair of mounting

posts

226 and 227 may be provided, each of which is shaped to mate with the socket on a camera of the type generally available for use with percussive flashcubes, such as that described in US. Pat. No. 3,602,6l8,for example. In such case, either the camera would be modified to render the socket non-rotating, or each of the

posts

226 and 227 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 flashcubes. In addition, the camera would be modified to remove the sensing portion of the operation, or spring 218 would be sufficient to prevent lever 210 from releasing the gears during the sensing movement of actuating member 224.

In the illustrated flash assembly 110, eight lamps are available to be sequentially flashed in response to suecessive indexing of the gear train by member 224. More specifically, with post 226 plugged into the above type camera, four rapid flash exposures may be taken, expending in sequence lamps 121-124. The array is then removed from the camera, reversed, and remounted to place the unused lamps 125-128 and preenergized strikers 135-138 in position to be operated. lnthis latter case, post 227 is inserted in In this camera socket, which post 226 overhangs the edge of the camera. Bar 184 is identical to bar 168, with similar self-energized indexing means, and channel 182 contains an aperture, similar to aperture 222, through which bar 184 may be indexed by member 224 in this reversed position of the assembly. Lamps -128 may then be sequentially fired in the same manner as lamps 121-124.

The sequence of releasing the strikers in response to successive indexing is programmed by the number and respective location of the ramps along the length of each slidable bar. In this case, four ramps on each bar are arranged so that for a selected increment x of translation along the respective channel, the bar travel will cause a first ramp on that bar to release a striker and a second ramp on that bar to be moved to a position adjacent another preenergized striker. This pattern of ramp positioning then continues for all successive x increments of translation until all for springs have been released.

For example, referring to FIGS. 9-11, according to one embodiment, the springs 131-134 are evenly spaced, with a common distance D between strikers (FIG. 8). Each of the ramps 171-174 is adapted to release a respective one of the striker springs 131-134, and each successive ramp after the first (ramp 171) is spaced D (n l)x from its preceeding' ramp in the striker release sequence, where D is the distance between strikers, n is the number of the ramp in 'the striker release sequence, and x is the distance the slidable bar 168 translates along channel 176 during each indexing increment for release of a striker. Thus, in FIG. 11, ramp 171 is positioned adjacent the striker spring 131, which is the first to be released in the firing sequence. Ramp 172 is spaced D (2 l)x D x from ramp 171. Ramp 173 is spaced D 2x from ramp 172, and ramp 174 is spaced D 3:: from ramp 173. Accordingly, the spring release sequence will be (1) spring 131 by ramp 171; (2) spring 132 by ramp 172; (3) spring 133 by ramp 173; and (4) spring 134 by ramp 174.

The new position of the gear train is retained after each indexing cycle by means of the spring loaded lever 210, which returns protrusion 216 to engage the next pin on bar 168. Hence, by virtue of the mechanical firing system, the ramp programming, and the spring lever control, 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 though the unit may have been removed from a camera and subsequently replaced.

Flg. 13 illustrates an alternative latching lever and index pin arrangement suitable for controlling the indexing of a slidable bar mounted on avertical supporting wall, such as employed in the planar array of flashlamps described in the aforementioned copending application Ser. No. 3 l5,8 12. In this instance a lever 230 loaded by a spring 232 engages a pin 234 projecting vertically downward from a side mounted slide bar 236.

Although the invention has been described with respect to specific emobidments, 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 with respect to FIGS. 1-6, 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 may vary. The gears can be arranged in various ways, yielding vertical, square, rectangular, T-, or L-shaped gear train configurations. The gears may be indexable by means other than the pins 61-68 and 71-78. Further, flat rotating members other than spur gears may be employed, and means other than ramps may be employed for selectively releasing the strikers.

With respect to FIGS. 7-13, the number of springs and lamps in the array may be varied, and the assembly may comprise but a single row of any reasonable plurality of lamps in lieu of the 4/4 bidirectional arrangement of the described embodiment. For example, the assembly could comprise a linear array of 8 or lamps all facing in the same direction. Further, thesliding bar could move from right to left, and spring release could be effected by moving the catches 162 downward, instead of lifting the strikers, e.g. by inverting each ramp for striking a projection from a flexible spring foot 160.

What I claim is:

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 pre-energized strikers mounted on said support member and releasable to fire said flashlamps, the selective actuating mechanism comprising:

a movable member;

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

means projecting from saidmovable member and adapted for selectively releasingsaid preenergized strikers;

means for spring loading said movable member suffrciently to cause indexing thereof; a plurality of evenly spaced index stops provided on said movable member; and,

a releasable latchingmeans normally engaging one of said index stops to lock the position of said movable member and operablefor momentarily releasing said spring loaded movable member to permit indexing thereof until said latching means engages the next one of said index stops;'

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

2. The mechanism of claim 1 further'including means for spring loading said latching means.

3. The mechanism of claim 2 wherein said latching means comprises a lever supported in operative relationship to said movable member and operative upon actuation to release said spring loaded movable member to permit indexing thereof by an amount determined by the spacing between said index stops. 7

4. The mechanism of claim l'wherein said movable member comprises a gear, said supporting means comprises a. portion of said support member shaped to provide a stationary shaft upon which said gear is'rotatably mounted, said shaft having a free end with a substantially planar surface parallel to the plane of said gear,

said flashlamps and strikers are mounted on saidplanar surface at the free end of said shaft with said preenergized strikers. 'being disposed radially thereon, and said spring loading means comprises a flat spiral spring mounted on said shaft and connected to said gear for urging said gear to rotate about said shaft.

5. The mechanism of claim 4 wherein said index stops comprise a plurality of circumferentially spaced pins on said gear.

6. The mechanism of claim 5 wherein said latching means comprises a spring loaded lever mounted in operative relationship to said gear and operative upon actuation to release said spring loaded'gear to permit rotation thereof by an amount determined by the circumferential spacing between said pins.

7. The mechanism of claim 4 further including a second gear intermeshed with said first-mentioned gear, said second gear being rotatably mounted upon a second stationary shaft provided on said support member, said second shaft having a free end, a plurality of said flashlamps and strikers being mounted on a substantially planar surface at the free end of said second shaft with said strikers disposed radially thereon, and said second gear having means projecting therefrom for selectively releasing the preenergized strikers on said second shaft.

8. The mechanism of claim 7 including a second flat spiral spring mounted onv said second shaft and connected to said second gear for urging said gear to rotate about said shaft.

9. .T he mechanism of claim 1 wherein said movable membercomprises a slidable bar, said plurality of flashlamps are mounted in a row'on said support member, said supporting means comprise a longitudinal channel in said support member located parallel to said row of flashlamps, and said spring loading means comprises an extension coil spring connected between said support member and said slidable bar for urging said bar to translate along said channel.

10. The mechanism of claim 9 wherein said index stops comprise a plurality of linearly spaced pins on said slidable bar, said pins projecting parallel to said support member.

11. The mechanism of claim 10 wherein said locking means comprises a spring loaded lever mounted in operative relationship'to said slidable bar and operative upon actuation to release said spring loaded slidable bar to permit translation thereof'along said channel by an amount determined by ,the linear spacing between ii ins- 12; The mechanism-of 'c'limi'i where'the preen gized strikers mounted on said support member project beyond the periphery of said channel to overlie a portion of said slidable bar, and said means projecting from said slidable bar comprises one or more ramps linearly disposed along one side of said bar, said sequence upon actuation to alternately engage the pins on said 4 slidable bar by means of said protrusions.

14. 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;

thefree 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 indivdually releasable to fire a respective one of said flashlamps; I

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

means for spring loading at least one of said gears sufficiently to cause indexing thereof;

a plurality of evenly spaced indexing stops provided on at least one of said gears; and,

a releasable latching means mounted on said support member and normally engaging one of said index stops to lock the position of said gear train, said latching means being accessible to be actuated for momentarily re-leasing said spring loaded gear train to permit indexing thereof until said latching means engages the next one of said index stops;

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

15. The assembly of claim 14 wherein said spring loading means comprises a flat spiral spring mounted on one of said shafts and connected to the 'gear on that shaft for urging that gear to index said gear'train.

16. :The assembly of claim 15 wherein said index stops comprise a plurality of circumferentially spaced pins on at least one of said gears, said pins projecting normal to the plane of the gear and being disposed near the periphery of the gear.

17. The assembly of claim 16 wherein said locking means comprises a spring loaded lever operative upon actuation to release said spring loaded gear train to permit indexing thereof by an amount determined by the circumferential spacing between said pins.

18. The assembly of claim 17 wherein the radially mounted strikers on each shaft project beyond the periphery of the planar surface thereof to overlie a portion of the gear mounted thereon, and said means projecting from said gears comprises one or more ramps on each of said gears, said sequence of releasing said strikers being programmed by the number and circumferential location of said ramps on each gear.

19. The assembly of claim 17 wherein said index stops comprise a plurality of circumferentially spaced pins on each of two adjacent ones of said gears, said lever is mounted on said support member by a substantially centrally disposed fulcrum means, and said lever has protrusions at each end for alternately engaging the pins on said two adjacent gears during actuation of said lever.

20. The assembly of claim 15 including a second flat spiral spring mounted on another of said shafts and connected to the gear on said last mentioned shaft for urging that gear to index said gear train.