GB1334536A - Indicating devices - Google Patents

Abstract

1334536 Indicating device AGFA-GEVAERT A G 5 Nov 1970 [5 Nov 1969] 52685/70 Addition to 1329258 Heading G1J A modification of the indicating device of the parent Specification 1329258 comprises a plurality of rotatable pointers 5, 6 having parallel spaced axes of rotation, a scale 9 and a reflecting surface 2. The free end 7 of each pointer is parallel to the axes of rotation and is viewed by reflection in the surface 2 of prism 1 along with a corresponding portion of scale 9 so that each pointer end portion 7 appears to move laterally. A separate scale 10, 11 may be provided for each pointer or a single scale may cooperate with several pointers and the scale may be in front of or behind the pointer ends. The pointers may be hidden at the ends of their travel by opaque areas on the prism 3 or scale 9 so that if each pointer starts to move as the previous one reaches the end of its travel the observer appears to see a single pointer travelling along the scale. In Figs.1, 2 control device 28 is actuated when lever 25 is depressed and is arranged to switch moving coil unit 3 off and moving coil unit 4 on when image 30 of pointer end 7 reaches the end of its travel. Alternatively a pointer may be arranged to actuate a switch when it reaches the end of its travel to actuate the next pointer. As a further alternative the pointers may be set manually by a transmission arranged to operate each in turn as the previous one reaches the limit of its travel. Slides 16 may be arranged to be manually movable to a position between illumination device 17 and reflecting surface 2, Fig.1, or between the pointer ends 7 and the reflecting surface or the scale, Fig. 4. At least parts of the scale may also be manually movable by a setting device. The slides and the scale may be coloured and different colours may be used to identify different portions of the scale. Alternatively the slides may be opaque. In Fig. 1, operation of lever 25 not only actuates device 28 but inserts coloured slide 16 into position. In the embodiment of Fig. 4, actuation of the lever removes an opaque slide from a position in which it obscures the pointers. The face of the prism 3 adjacent the pointer ends may be curved e. g. cylindrical and may have the scale thereon. In a modification, the prism 1 is bevelled at the intersection of faces 2 and 8 and provided with a scale visible through the bevelled surface. The scale 9 may then be omitted.