GB717334A - Photographic camera including a device for locking the exposure-counting and film-winding means - Google Patents

Abstract

717,334. Photographic roll-film cameras. GRANGE, A. Nov. 6, 1951 [Jan. 23, 1951], No. 26005/51. Class 98(1) A photographic roll-film camera includes a locking device which comprises a manually operated rotatable spindle carrying at one end thereof a first lever adapted to lock film winding means and at ihe other end thereof a second lever adapted to lock exposure counting means, the release of the film winding means and the exposure counting means being effected after each exposure by rotation of the rotatable spindle. As shown, the film 2 is wound on to a take-up spool 1 rotated by a crank 15 through gearing 14, 16 and 17. The film 2 is spring-urged against a roller 3 geared through 'gearing including a frictional connection to the exposure-counting wheel 4 carrying numerals or reference markings visible through an inspection window. The spindle of the wheel 4 carries two discs 5 and 6. The disc 5 is fixed on the spindle and carries notches 5<SP>1</SP>. 5<SP>2</SP> equal in number to the number of picture areas, the notch 5<SP>2</SP> being much less deep than the notches 5<SP>1</SP>. The disc 6 is loose on the spindle and carries shaped abutments 6<SP>1</SP> corresponding in number and position to the notches 5<SP>1</SP> 5<SP>2</SP>, and is connected to the disc 5 by a spring permitting relative movement of the discs 5 and 6. A spindle 9 provided with a central knob 18 carries, at one end, a lever 8 having a lug 8<SP>1</SP> engaging, under the action of the spring 19, the notches and abutments on the discs 5 and 6 and, at the other end, a lever 10 carrying a projection holding a nose on the spring-urged locking, lever 12 out of engagement with the teeth on the gear 14. The film is wound by operation of the crank 15 until the normal mark on the backing paper corresponding to the first exposure frame is visible in the normal aperture in the back of the camera, and after the first exposure the knob 18 is rotated to release the lug 8<SP>1</SP> from the notch 5<SP>2</SP> and permit further winding of the film until the lug 8<SP>1</SP> encounters the next abutment 6<SP>1</SP> to stop rotation of the disc 6 The wheel 4 and the disc 5 continue to rotate until the first notch 5<SP>1</SP> is uncovered, whereupon the lug 8<SP>1</SP> engages in this notch and the consequential pivotal movement of the lever 8 and rotation of the spindle 9 causes lever 10 to release lever 12 to lock the gear 14 and prevent further winding of the film until the exposure is made and knob 18 again rotated. When the last. exposure has been made. the lug 8<SP>1</SP> re-engages the notch 5<SP>2</SP> of reduced depth, and hence the lever 12 does not move sufficiently to lock wheel 14. The winding may accordingly be completed, the frictional drive to the wheel 4 slipping. The exposure-counting mechanism may be mounted on one plate and the film-winding mechanism on another, to facilitate assembly and repair of the camera.