US3609333A

US3609333A - Flashbulb holder for photographic flashuns

Info

Publication number: US3609333A
Application number: US802545*A
Authority: US
Inventors: Masahiko Iwaki; Hazime Kogawa
Original assignee: Honeywell Inc
Current assignee: Pentax Corp
Priority date: 1968-03-01
Filing date: 1969-02-26
Publication date: 1971-09-28
Anticipated expiration: 1988-09-28

Abstract

A flashbulb holder for a photographic flashgun is shown having a housing with an opening into which various-sized flashbulbs are inserted between a pair of pivoted holding members mounted on opposite sides of the opening. A pair of base contact members engage the flashbulbs, as they are inserted between the holding members, for urging the bases of the flashbulbs against the inner edges of the holding members. A potential source connects to the base members for selectively energizing the flashbulbs.

Description

United States Patent Masahiko lwaki inventors Fuiisawa-shi; llazime Kogawa, Tokyo, both of Japan Appl. No. 802,545 Filed Feb. 26, 1969 Patented Sept. 28, 1971 Assignee Honeywell lnc. Priority Mar. 11, 1968 Japan 43/ 15756 FLASl-IBULB HOLDER FOR PHOTOGRAPHIC FLASHGUNS 3 Claims, 4 Drawing Figs.

US. Cl 240/ 1.3, 339/45 T Int. Cl 011' 13/62 240/ 1 ,3; 339/32, 33, 45 T References Cited UNITED STATES PATENTS 1,260,085 3/1918 Snyder .t 339/33 2,912,665 11/1959 lrwin 339/45 T X 2,920,301 1/1960 Kawate..... 339/45 T X 2,976,511 3/1961 Lipsitz 339/45 T X 3,067,399 12/1962 Matsui.. 339/33 3,259,868 7/1966 lrwin t. 339/45 T X Primary ExaminerSamuel S. Matthews Assistant Examiner-Robert P. Greiner Anorneys--Arthur l-l. Swanson and Lockwood D. Burton ABSTRACT: A flashbulb holder for a photographic flashgun is shown having a housing with an opening into which varioussized flashbulbs are inserted between a pair of pivoted holding members mounted on opposite sides of the opening. A pair of base contact members engage the flashbulbs, as they are inserted between the holding members, for urging the bases of the flashbulbs against the inner edges of the holding members. A potential source connects to the base members for selectively energizing the flashbulbs.

PATENTEnsiPalsn 3609.333

INVENTORS.

MASAHIKO IWAKI 9 BY HAZIME KoeAv A r W ATTORNEY.

FLASHBULB HOLDER FOR PHOTOGRAPHIC FLASHGUNS The present invention relates to a flashbulb holder for a photographic flashgun which mounts a flashbulb having a base of any type or size in such a location that the center of illumination of the flashbulb is in an aligned relationship with the focal position of a reflector associatedwith the flashgun.

Prior art photographic flashguns are generally adapted to receive a flashbulb of a particular base size. When it is desired to utilize a flashbulb of a different base size, it is normally required to obtain a different flashgun. Some prior art flashguns, however, are arranged to receive flashbulbs of various base sizes. These flashguns are provided with a reflector having a particular mirror surface adapted for a particular flashbulb which cannot be modified to efficiently reflect the light ofthe various-sized flashbulbs mounted therein.

Prior art flashguns are not adapted to receive the older bayonet-type flashbulb and the newer AG-type flashbulb within the same flashbulb-holding socket. Further, the prior art flashguns are not capable of receiving a plurality of flashbulbs in such a manner that the center of flash corresponds with the focal position of the reflector.

Accordingly, it is an object of the present invention to provide a flashgun with a flashbulb-holding socket which is capable of mounting various-size flashbulbs. I

Another object of the present invention is to provide a flashgun which is capable of mounting a plurality of flashbulbs having their center of flash aligned with the focal position of the flashgun reflector.

A further object of the present invention is to provide a flashgun with a simplified method of ejecting the flashbulb therefrom.

Still a further object is to provide an improved flashgunholding socket which is simple in construction, low in cost, and dependable in operation.

A In accomplishing these and other objects, there is provided aflashbulb holder for a photographic flashgun having a pair of flashbulb-holding means pivoted on opposite sides of a guide opening located within the housing. The flashbulb-holding means effectively close the guide opening from the inside. As a flashbulb is inserted between the flashbulb-holding means into the guide opening, it engages base contact means which are resiliently urged against the flashbulb. The flashbulb is inserted until the opposite inner edges of the flashbulb-holding means engage and hold the flashbulb against the urging of the base contact means for retaining it within the socket.

Further objects and many of the attendant advantages of the present invention will become apparent from the following description, when considered with reference to the accompanying drawings, wherein:

FIGS. la and lb are vertical sections diagrammatically showing holding positions of the flashbulb holder for two dif ferent types of flashbulbs;

FIG. 2 is an exploded perspective view of the flashbulb holder according to the present invention; and

FIG. 3 is a perspective view of the flashbulb holder according to the present invention.

Referring now to the drawings, and more particularly to FIGS. 1a and lb, a flashbulb holder is shown generally at 1 having guide opening 2 which receives any one of a plurality of various-sized flashbulbs. The guide opening 2 is closed by a pair of flashbulb-holding members 5 which are pivotally supported on opposite sides of the opening upon pins 3. The flashbulb-holding members 5 operate to close the guide opening 2 and are urged into the closing position by springs 4, FIG. 2, coiled upon the pins 3.

As best seen in FIG. 2, the flashbulb-holding members '5 each include a main portion 51: having upper and lower halves, one of which extends as a tab which terminates at an inner edge 5a. Each tab extends from its flashbulb-holding member toward the recess, formed by the absence of a tab half on the opposite flashbulb-mounting member, for closing the guide opening 2. .A portion of each flashbulb-holding member extends from the fulcrum point formed by the pins 3 away from the opening 2. This extended portion forms a tail portion 5c which cooperates with the ejector arrangement of the flashbulb holder to be described hereinbelow. A pair of base contact members 6 is located at the bottom of the guide opening 2 within the holder 1. Rods 6a extend from they base members 6 for attaching a pair of springs 7 thereto. The springs urge the basecontact members 6 against the base of a flashbulb, as it is inserted into the guide opening 2 of the flashbulb holder 1.

The flashbulb holder is provided with an electrical circuit which includes a switch 8 that normally works in synchronism with the shutter of a camera, not shown. A potential energy source is provided, such as a DC battery E, having its negative terminal connected through the spring 7 to one of the base members 6 and its positive contact connected to the common terminal of the switch 8; The normally open terminal of the switch 8 is then connected through the second spring 7 to the second base member 6. This circuit operates to' fire-a flashbulb when the switch 8 is closed by the action of the camera shutter, as will be described hereinbelow.

As shown in FIG. 2, the flashbulb housing is formed from a socket 10 having a centrally relieved portion along its longitu dinal axis that forms the lower portion of the guide opening2. The rods 6a pass through the socket 10 and are retained therein, as by shoulders. The springs 7 are mounted over each rod 6a for urging the base contact members 6 along the guide opening 2 toward the flashbulb-holding members 5. A tab portion 6b extends from the edge of one of the base contact members to contact the outer edge of the base of a larger flashbulb, as the flashbulb is inserted into the guide opening 2. This contact pushes the base contact member 6 down and out of the way for allowing the second base contact member 6 to contact the center of the larger flashbulb. When smaller flashbulbs are utilized within the flashbulb holder 1 the two base contact members each contact the base of the flashbulb. This arrangement will be further described hereinbelow.

The socket 10 is also provided with a pair of slots which receive the legs of a U-shaped ejector 11. The ejector I1 is provided with a pair of springs 12 for urging the ejector away from the tail portions 5c of the flashbulb-holding members 5. A pushbutton 13 is arranged to engage the base of the U- shaped ejector 11. The pins 3 and springs 4, which pivotally mount the holding members 5, fit within a relieved portion located at the top of the guide opening 2 within the socket I0. A holding frame 14 is placed over the pins 3 and holding members 5 for securing them within the guide opening 2.

The outer periphery of the holding frame 14 provides a cylindrical shoulder upon which reflector blades 16 may be rotatably mounted. Retaining of the reflector blades is accomplished by a reflector-holding plate 15 secured, as by screws, against the holding frame 14.

Referring now to FIGS. 1a and lb, the operation of the flashbulb holder will now be explained. As a larger flashbulb 17 having a bayonet-type or M-type base 17a is inserted into the opening 2, the holding members 5 yield in a downward direction against the urging of the springs 4 for enlarging the guide opening 2. Upon further insertion, the tab 6b on one of the base contact means 6 contacts the outer lowermost edge of the base 17a for causing the base contact 6 to yield with the inward thrust. The flashbulb I7 is inserted until the inner edges 5a of the holding members 5 fall into a groove 17b within the base 17a. At this point, the urging of the springs 4 cause the inner edges 5a to engage the groove 17b and hold the flashbulb 17 against the outward force exerted by the spring-loaded base contact member 60. The tab 6b, having forced its base contact member down below the flashbulb I7, contacts the edge of the flashbulb base 17a,- while the second base contact member 6 contacts thecenter contact of the base 17a. Thus, when the switch 8 is closed, the positive terminal of the potential source E is connected through spring 7, base contact 6 and tab 6b to the outer edge of the flashbulb 17. The negative terminal of the potential source E is connected through the second spring 7 to the second base contact 6 and then to the center contact of the flashbulb base for firing the flashbulb. After the flashbulb 17 has been fired, the pushbutton 13 is depressed for urging the legs of the U-shaped ejector ll upwardly against the tail portions 50 of the holding members 5. This causes the main portion b of the holding members 5 to be pivoted downwardly for releasing their hold on the groove 17b and allowing the spring-loaded base contact members 6 to urge the flashbulb 17 from the socket.

In FIG. 1b, a flashbulb 18 of the AG-type is inserted into the guide opening 2 where its base 18a contacts the holding members 5. The holding members 5 resiliently yield, until the base 180 has passed therebetween, and then engage a groove 18b within the base of the flashbulb 18. It will be noted that the base 18a is substantially narrower than the base 17a of the M- type or bayonet-type flashbulb. Thus, the tab portion 6b of the base contact 6 does not engage the outer edge of the base. The two base contacts 6 each engage a portion of the base 18a and the contact wires thereof, located on each end of the narrow base l8a.When the switch 8 is closed, a positive potential from the source E is applied through one base contact 6 to one side of the flashbulb base, while the potential from the source E is applied through the other base contact member to the other side thereof. Thus, activation of switch 8 causes the flashbulb 18 to fire. Again, ejection is accomplished by depressing the pushbutton 13 for engaging the tail portions 5c with the legs of the U-shaped ejector 11 thus urging the main portions 5b downwardly for allowing the spring-loaded base contact members to eject the flashbulb 18 from the holder 1.

It will be observed that the flashbulb 17 has a center of flash or illumination 19 while the flashbulb 18 has a center of illumination 20. These centers are located at different points within the bulbs. The present invention has been arranged to allow the illumination centers to be aligned with a focal position 21 formed by the reflector plates 16 when they are expanded and clamped together for forming the reflector mirror. Through the unique design of the flashbulb holder, the larger flashbulb 17 is inserted deeper into the flashbulb holder for aligning its center of illumination with the focal position of the reflectors 16. Similarly, the flashbulb 18 is not inserted as deeply into the flashbulb holder for aligning its center of illumination with the focal position 21 of the reflectors 16. Thus, the flashbulb holder of the present invention may be utilized to mount a plurality of various-sized flashbulbs having different centers of illumination, within a common flashgun having a reflector with a fixed focal position.

Accordingly, the flashgun of this invention has the advantage that it can securely hold any one of the bayonet-type, M-type or AG-type flashbulbs without regard to the form of the base and without regard to the location of the center of illumination.

Obviously, many modifications and variations of the present invention will become apparent to those skilled in the art in light of the above. Therefore, the present invention should be limited only by the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A flashbulb holder for a photographic flashgun capable of receiving various flashbulbs having variously sized bases and bulbs, comprising:

housing means having an opening therein;

a pair of flashbulb-holding means pivotally supported within said housing for receiving, one at a time, said various flashbulbs therebetween;

fulcrum means, about which said flashbulb-holding means are pivotally supported, arranged on opposite sides of said opening;

a pair of base contact means arranged for connection to a potential source and resiliently arranged to contact contacts on said base of said flashbulbs, as said flashbulbs are received between said flashbulb-holding means, for urging said flashbulbs against said flashbulb-holding means thereby holding said flashbulbs therebetween; said pair of base contact means being resiliently arranged to be individually urged against said variously sized bases of said flashbulbs for providing proper contact with said contacts on said bases,

said flashbulb-holding means being arranged to resiliently close said opening and including tail portions extending away from said opening; and

a movable ejector means engaging said tail portions of said flashbulb-holding means for causing said flashbulb-holding means to open from said opening upon movement of said movable ejector means thereby ejecting from said holder a one of said flashbulbs held by said holding means.

2. A flashbulb holder as claimed in claim 1, wherein:

said pair of base contact means includes spring means for resiliently mounting said base contact means within said opening of said housing means;

said pair of base contact means are symmetrically arranged within said opening of said housing means for contacting each contact of the base of a smaller based one of said flashbulbs as the latter is inserted into said opening; and

a tab portion extends from one of said pair of base contact means for contacting the edge of the base of a larger based one of said flashbulbs as the latter is inserted into said opening, thereby allowing the other of said pair of base contact means to contact the center contact of said base of said larger based flashbulb.

3. A flashbulb holder as claimed in claim 1, wherein there are included reflector means mounted upon said housing means and having a fixed focal position; wherein each of said flashbulbs has a center of illumination; and wherein said flashbulb-holding means is arranged to oppositely yield for holding the base of a larger based one of said flashbulbs at one holding position thereon against the urging of said resiliently arranged base contact means while holding the base of a smaller based one of said flashbulbs at a different holding position thereon to cause the center of illumination of each of said flashbulbs to be aligned with said focal position of said reflector.

Claims

1. A flashbulb holder for a photographic flashgun capable of receiving various flashbulbs having variously sized bases and bulbs, comprising: housing means having an opening therein; a pair of flashbulb-holding means pivotally supported within said housing for receiving, one at a time, said various flashbulbs therebetween; fulcrum means, about which said flashbulb-holding means are pivotally supported, arranged on opposite sides of said opening; a pair of base contact means arranged for connection to a potential source and resiliently arranged to contact contacts on said base of said flashbulbs, as said flashbulbs are received between said flashbulb-holding means, for urging said flashbulbs against said flashbulb-holding means thereby holding said flashbulbs therebetween; said pair of base contact means being resiliently arranged to be individually urged against said variously sized bases of said flashbulbs for providing proper contact with said contacts on said bases, said flashbulb-holding means being arranged to resiliently close said opening and including tail portions extending away from said opening; and a movable ejector means engaging said tail portions of said flashbulb-holding means for causing said flashbulb-holding means to open from said opening upon movement of said movable ejector means thereby ejecting from said holder a one of said flashbulbs held by said holding means.

2. A flashbulb holder as claimed in claim 1, wherein: said pair of base contact means includes spring means for resiliently mounting said base contact means within said opening of said housing means; said pair of base contact means are symmetrically arranged within said opening of said housing means for contacting each contact of the base of a smaller based one of said flashbulbs as the latter is inserted into said opening; and a tab portion extends from one of said pair of base contact means for contacting the edge of the base of a larger based one of said flashbulbs as the latter is inserted into said opening, thereby allowing the other of said pair of base contact means to contact the center contact of said base of said larger based flashbulb.