Patent GB-410630-A (GB)
Title: Improvements in or relating to apparatus for timing races or other events
IPC: G03B15/00
Filed: 1933-06-28
Abstract: 410,630. Timing races. ELECTRICAL RESEARCH PRODUCTS, Inc., 195, Broadway, New York, U.S.A.-(Assignees of Kirby, G. T. ; 1100, Park Avenue, New York, U.S.A.) June 28, 1933, No. 18416. Convention date, July 1, 1932. [Class 106 (iv).] A kinematograph camera for timing races and other events is combined with a chronometer and an optical system for projecting simultaneously on the film images of the chronometer and an extraneous scene, the operation of the chronometer being controlled by manually operated means in the camera and by a solenoid under remote control. An indicating lamp adapted to be illuminated at will, preferably at the start of a race, may be used to make a mark on the film. In the form shown in Figs. 6 and 11, a bracket 41 is clamped over the lens end of a kinematograph camera 40 of standard design and carries a tube 42 to which is attached by clamping collar 50 a light tight box 51 containing the chronometer, e.g. a stop watch 52. The latter is mounted in a circular bracket 55 and illuminated by lamps 53, the light therefrom passing through the box 51, tube 42, an aperture 44 in the lens mount 43 of the camera, to an adjustable prism 45 and from thence through the lens system 46 to the shutter 47 and a portion of the film, a mask 48 being provided at the film gate to separate the external image from the chronometer image. The stop watch 52 may be started and stopped by a solenoid operated automatically from the starting position or camera position. In the latter case a control button on the bracket 41 is arranged to close firstly the circuits for lamps 53 and solenoid 57 and then to start the camera. The stop watch may, however, be manually operated by a button 69 on the solenoid 57. A signal indicating the start of the race may be provided by an electronic lamp mounted in the box 51 in the field of the lenses and arranged in a circuit having spring contacts closed by the hammer spring of the starting pistol. Alternatively spring contacts 107, 108, Fig. 29, for the electronic lamp or solenoid 57 may be mounted in a housing 105 fixed to the muzzle of the starting pistol, the contacts being closed by the gases from the explosion. In a modification the lamps 53 and solenoid 57 may be brought into operation by a mercury switch closed when the pistol is raised preparatory to the start or by a microphone responding to the report or a photo-electric cell responding to the flash of the pistol. In a modification, Fig. 32 the stop watch is replaced by a series of concentric dials 110 or overlapping dials geared to a shaft 175 adapted to be clutched to a synchronous motor 161. The latter is in circuit with a battery and valve 135, the grid of which is connected to a pick up coil 134 arranged near a tuning fork 130 vibrated by a circuit including electromagnet 131, contacts 133, and battery 132. The clutch members 17 4, 17 7 are pressed into engagement by a spring urged lever 171 but are normally held apart by a latch 169. A solenoid 162 energized by contacts in the starting pistol is arranged to withdraw the latch and free the lever 171. Various control arrangements for starting and stopping the camera and chronometer, and for illuminating the signal lamp and lamps 53 are described. The signal lamp may be arranged to illuminate the chronometer and record the starting time on a stationary film, the camera being brought into operation only at the end of the race. A number of cameras recording different stages of a race may be used, a signal being made in each at the start of the race to enable the records to be correlated.