GB1295886A - - Google Patents

Abstract

1295886 Targets BRUNSWICK CORP 2 Feb 1970 [14 Feb 1969] 4825/70 Heading A6S [Also in Division G4] The position at which an arrow passes through a flexible target 24 is reproduced a screen 54 close to the archer. The target is painted or projected on a screen 22 made flexible strands. The arrows are stopped by net and returned by a conveyor 40 described in Specification 1295887. A light beam narrower than an arrow is projected by a light on to two continuously rotating mirrors at the top and bottom of a column so that in respect of each target, two beams periodically sweep across retro-reflective tapes (106). As each scan begins a photo 108, Fig. 7, sets bistable 304 to start a count on BC1-BC64. In the absence of an arrow the counter reaches full capacity and then zero so that AN gate 316 resets bistable 304. If the scan detects the passage of an arrow then diffusion of the light beam energises a photo-cell 140 (also Fig. 5) to reset 304 and halt the count at a value representing the angular coordinate of the arrow. At the same time a flip-flop 320 initiates a read period of 5 seconds. A comparator 336 compares the readings of a conductive-segment coded disc 338 (also Fig. 8) with the counter and causes a motor 359 to sweep on arm 357 over the target indicator 54 until equality is attained. Two arms 357 are provided in respect of the two scans. When the movements are completed a lamp 356 lights to indicate where the arrow has hit. An electromagnetic brake 364 is operative whenever the motor is de-energised. A bulls-eye lights a lamp 388 and rings a bell. The number of arrows detected is registered by a counter 366 which can be reset by button 372.