US2443357A

US2443357A - Photographic lamp

Info

Publication number: US2443357A
Application number: US640804A
Authority: US
Inventors: Robert R Mcmath; Stephen J Menzel
Original assignee: MOTORS METAL Manufacturing Co
Current assignee: MOTORS METAL Manufacturing Co
Priority date: 1946-01-12
Filing date: 1946-01-12
Publication date: 1948-06-15
Anticipated expiration: 1965-06-15

Description

R. R. M MATH ETI'AL June 15, 1948.

' PHO'TOGRAPHIC LA P,

2 Sheets-Shet 1 Filed Jan. 12, 1946 1 06a? at e heni the angle for the other end extending slightly beyond the opposite end of the sleeve 2|. A cap 23 is fitted on the last-named end of the sleeve and is clamped to the tube 22 by a screw 24 passed through the cap and threaded into the outer end of the tube 22.

The sleeve 2! consists of a pair of semi-cylindrical shells 25, each having outwardly extendin

flanges

26, 27 at its edges, the flanges 26 of each member being secured in surface contact with the flanges 21 of the other member. The flanges 21, lying on opposite sides of the axis of rotation, are extended laterally in opposite directions as indicated by the numeral 28 in Fig. 3. The extensions 28 may, if desired, be ribbed at 29 across reinforcement. supports a conventional lamp socket 30. sockets, bein disposed on corresponding surfaces of the extensions and at corresponding points thereof, are related symmetrically with respect to the axis of the trunnion l9.

As shown in Figs. 1 and 3, the sleeve 2| may be provided with a pair of reflector brackets 3| also disposed symmetrically with respect to the axis of the trunnion it. These brackets may be secured, for example, to the respective flanges 21 of the shells 25. The brackets 3| carry reflectors 32 properly arranged with respect to lamps mounted in the sockets 30, as will presently be shown.

One of the sockets carries a lamp A of high intensity on the order of 200 watts. This is a conventional or standard incandescent lamp. The other socket 30 carries a photographic flashlight bulb B.

The result of the described symmetrical arrangement of the lamp sockets and reflectors with respect to the axis of the trunnion I9 is that the lamps A, B, being of similar shape, also have corresponding points thereof symmetrically disposed with respect to the axis of rotation of the sleeve 2|. The critical requirement, however, is that the respective centers of illumination of the lamps be disposed symmetrically with respect to the axis of rotation of the sleeve 2 i. This condi tion is indicated by the center line X in Fig. 3. Consequently, if the sleeve is rotated 180 from the position shown in Fig. 3, the lamps A and B will occupy the exact positions formerly held by the lamps B and A. The reflectors 32' are, of course, positioned for the most elfective and efiibrackets 21, a reflector 40 may be provided with the customary threaded neck 4| and screwed r directly as shown in Fig. 6 upon the screw threads 30a provided on the standard lamp sockets 30, the latter being the preferred construction.

In the use of the device, the incandescent lamp A with its reflector 32 is positioned for the desired illumination of the subject to be photographed. The adjustment is made by first setting the support or post Hi, which is usually portable, then adjusting the bracket H, I2 on the post by the screw I and flnally tightening the bracket I 4, [5 at the desired angle to the bolt I! by means of the wing nut It as already described. The sleeve 2! is held against rotation about the trunnion 19 by means of a detent consisting of a, tube 35 mounted diametrically in the trunnion and hav- Each extension 28 1 The '= an arc of 180 ing a ball 36 at each end, the balls being held apart by a coil spring 31. The balls lodge in seats 38 formed between the inner ends of adjacent flanges 26, 21.

The balls 36, while maintaining the sleeve 2| in an end position, are yieldable to a turning force applied to the sleeve. When the incandescent lamp A has been properly adjusted on the subject, the device is swung manually through to bring the flashlight bulb B into the exact focusing position of the lamp A. This position is also maintained by the detent device. The shutter is then opened, with simultaneous flashing of the bulb B in the usual manner.

It is now evident that practically no time is lost in substituting the flashlight bulb for the incandescent lamp. Slnce the photographer need not wait for the incandescent lamp to cool and need not unscrew it, no complicated manipulation on his part is necessary, and the subject, if a living one, does not tire and does not impair the desired pose.

While I have shown a satisfactory constructional example of the present invention, it will be understood that many changes, variations and modifications of the specific constructional details may be resorted to without departing from the spirit of the appended claims.

We claim:

1. A flashead assembly comprising a trunnion, a pair of semi-cylindrical shells rotatably fitted on said trunnion and having outward flanges at their longitudinal edges, the flanges of each shell being secured to the flanges of the other shell to form a sleeve, each pair of attached flanges forming a seat in the inner wall of said sleeve, adetent in said trunnion adapted to cooperate 2. A. flashead assembly comprising a trunnion, a pair of semi-cylindrical shells rotatably fitted axis of rotation of said body.

- ROBERT R. McMA'I'H. STEPHEN J. MENZEL.

REFERENCES CITED The following references are of file of thispatent:

UNITED STATES PATENTS record in the