US2614783A

US2614783A - Pivotal disk clamp

Info

Publication number: US2614783A
Application number: US91599A
Authority: US
Inventors: Wesley J Spear
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-05-05
Filing date: 1949-05-05
Publication date: 1952-10-21
Anticipated expiration: 1969-10-21

Description

;Oct. 21, 1952 w. J. sPEAR- 2,614,783.2- PIVOTALIDISK CLAMP Filed May 5, 1949 '2 INVENTOR. WESLEY J. SPEAR AT OEVEYS.

Patented Oct. 21, 1952 UNITED STATES PATENT OFFICE This invention relates to removable clamping mechanism for the support of cover plates or discs such as the flashlight shield or filter plate illustrated herein.

Occasionally photographers flashlight bulbs explode when ignited, and throw the shattered glass with appreciable force outwardly from the reflector. If a close-up portrait is being taken at the time of such explosion the accident may result in serious injury. Hence most photographers shield the subjectwith a transparent 1 Claim. (Cl. 248226) disc which is customarily afilxed to the body of the flashlight reflector. In some types of work, such as flashlight color photography, filter discs are used in a similar manner; in either case, however, the discs heretofore 'in use have been attached to the reflector by a screw clamp which was cumbersome, unreliable unless firmly seated, and apt to mutilate the reflector or scar the finish thereof. The present invention contemplates a spring-pressed clamp which is designed to overcome the foregoing defects, and also accommodate the rigid support of a plurality of similar discs in an inoperative position irrespective the wear occasioned by repeated adjustments of the pivotal connection therein.

A further object and advantage of the improved clamp resides in the provision of a clip that may be readily attached or quickly removed from the reflector and a structure in which the clamping spring performs the dual function of holding the discs in their adjusted position and simultaneously urging the clamping arms against the body of the reflector.

Further objects and advantages more or less ancillary to the foregoing, and the manner in which all the various objects are realized, will appear in the following description, which, considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

Referring to the drawings:

Fig. 1 is a side elevational view of a photographers flashlight bulb holder illustrating the improved clamp and the discs supported thereby, in their assembled relation upon a reflector, a portion of the reflector being broken away and shown in section in the interest of clarity;

Fig. 2 is a front elevational view of the holder with one of the discs disposed in front of the reflector and other of the discs adjusted to an inoperative position;

Fig. 3 is a view in perspective of the improved clamp;

Fig. 4 is a side elevational view of another form of flashlight bulb holder and the reflector therefor, the figure further including a clamp of a modified form for use therewith;

Fig. 5 is a front elevational view thereof; and

Fig. 6 is a view in perspective of the clamp illustrated in Fig. 4 and a fragmentary portion of the discssupported thereby.

Referring first to Fig. l, the flashlight bulb and reflector holder are of conventional form, the structure embodying generally a bracket 10 adapted for adfixture upon a camera, a lamp socket H supported thereby, and a parabolic reflector [2. The improved shield or filter disc clamp is supported in spring-pressed relation on the edge of the reflector I2, the arms of the clamp being configured to maintain the discs in parallel relation to the plane of the rim of the reflector. As illustrated, three discs are carried by the supporting mechanism or clamp C, i. e., an inner transparent disc l3 constituting a shield to safeguard the subject being photographed, a

translucent disc 14 for diflusion of the light emanating from the flashlight bulb B, and a colored disc [5 for. filtering the rays of the bulb B 'when a white bulb is used in taking flashlight color pictures. Obviously the number or character of the discs or plates may be varied, the.

arrangement shown herein being merely illustrative of the utility of the clamp.

The improved clamping mechanism. comprises a pair of arms I 6 and I7 having openings therein intermediate their ends for the reception of a machine screw l8 which serves as an axis member with the components of a clamp mechanism constituting a pivotal support for the discs. The head of the machine screw forms a stop piece 'for the discs and the associated bearing washer.

The arms are formed from sheet metal spring stock of suflicient width to restrain pivotal movement thereof when engaged with the reflector. The inner arm it of the clamp is bent adjacent the opening therein to form a fulcrum IS. The lower end of the arm I! is bent rearwardly to form an inclined portion 40 for intimate engagement with the inner face of the marginal edge of the reflector l2 while the upper portion thereof is bent substantially normal to the axis of the screw l8. The lower end of the inner arm I6 is formed with an incline portion M for engagement with the outer face of the reflector while the upper end of the arm is disposed in divergent relation to the upper end of the arm IT. The screw I8 is provided with a helical spring 20 compressively retained against the arm Is by the nut 2| which is restrained against rotational movement by a jam nut 22.

In the assembly of the disc-supporting clamp upon a reflector the upper ends of the arms I6 and I! are forced together, thus separating the lower jaws thereof which are then positioned over the forward marginal edge of the reflector. The shield or disc to be used is then rotated about the screw [8, the remaining discs being elevated to an inoperative position, as shown in Fig. 2. It will be noted that the spring [8 which urges the jaws of the clamp into springpressed engagement with the reflector will also maintain frictional engagement between the discs and thus facilitate the support thereof in their elevated position irrespective the wear that may occur between the contiguous bearing surfaces thereof.

As illustrated in Figs. 4-, 5, and 6, the clamp is modified to accommodate the use thereof with a shallow reflector 30 of the type employed with a flashlight bulb of another form. In this embodiment the arm 3! is bent at an angle which will accommodate the seated engagement thereof with the inner face of the reflector, the upper portion of the arm, however, being bent laterally and downwardly for the support of the discs l3 and [4. The depending end 32 of the arm 3| is pierced for the reception of a machine screw 33 constituting the pivot for the shield or diffusion disc. The screw is provided with a helical spring 34 disposed in telescopic engagement therewith and retained in compressive engagement with the second arm of the clamp by a nut 35 which is restrained by a jam nut 36. The opening in the disks l3 and I4 is provided with sufiicient clearance to permit the discs to rotate freely on the screw and permit the head thereof to be drawn into frictional engagement with the outer disc M. The lower end of the inner arm 3! is normally disposed in parallel relation with the free end of the arm 3| the ends of both

arms including portions

42 and 43, respectively, inclined with respect to the remaining portions of the clamp for gripping the reflector 30. The upper end of arm 31 is bent at an angle in divergent relation to the horizontal portion of the arm 31. The opening 38 in the arm 31 is formed with sufiicient clearance over the shank of the screw 33 to facilitate the rocking movement of the arm about the shoulder or fulcrum 39 in the arm 3|. When the upper end of the arm 31 is pressed downwardly toward the horizontal portion of the arm 3| the lower ends of the jaws will be separated, and

4 upon release thereof the jaws will grip the re flector in self-sustaining engagement.

It will be recognized that the improved clamp may be employed in various environs other than the disc or shield associated with the flashlight reflector and such additional or further uses thereof are contemplated as falling within the scope and spirit of the invention as claimed.

I claim:

A clamp for the support of shield members from the wall of a reflector, comprising an axis member having a piece at one end adapted to serve as a stop for members fitted over the axis member, a first arm fitted over the axis member and adapted to bear upon members fitted over the axis member, the first arm comprising a piece having a central portion and an opening at one point therein for receiving the axis member, a portion adjacent one end of the central portion inclined at an angle thereto and an arcuate portion adjacent the axis member, a second arm fitted over the axis member including a central portion having an opening for receiving the axis member, a generally fiat portion inclined with respect to the central portion for cooperating with the inclined portion of the first arm to form a clamp, an arcuate portion for cooperating with the arcuate portion of the first arm to form a fulcrum whereby the arms may be pivoted with respect to the axis member and each other, and a portion extending beyond the arcuate portion to form an actuating grip, spring means fitted over the axis member for constraining the arm members with respect to each other and the axis member and adapted to constrain shield members placed over the axis member, and retaining means at the remaining end of the axis member for constraining the spring means with respect to the axis member.

WESLEY J. SPEAR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,089,080 Rauschert Mar.,3, 1914 1,800,756 Sass Apr. 14, 1931 2,441,489 Jacobs May 11, 1948 2,452,796 Skibsted Nov. 2, 19 48