GB398795A - Improvements in measuring instruments - Google Patents

Abstract

398,795. Measures of length. DALLEM, P., Rue de Forbach, KLING, P., 73, Rue de Lixing, both in Grosbliederstroff, and FRITZ, J., Place Foulin Ó Biet, Bousbach, both in Moselle, France. Dec. 17, 1931, No. 34949. Void [Abridged as open to inspection under Sect. 91 of the Acts, Dec. 20, 1931]. [Class 106 (ii).] An instrument of the running wheel type for measuring the length of curved or straight lines comprises the wheel 7 which is run along the line the length of which is required and which actuates through the wheel train shown, the pointers 14, 20, 26, 32 giving the length in say millimetres, centimetres, decimetres and metres respectively. The mechanism is mounted upon the casing 1, partition 5 and covers 3, 4 forming a watertight box. The pointers are observed through a transparent plate 35, e.g. of glass, retained by a cover-plate 36 held by screws 2 which serve to assemble the casing and the covers. To facilitate measurements an index 41 is provided. To zeroize the device a spring 42 has one end connected to the wheel 24 in the wheel train of the pointers and has the other end connected to a ratchet wheel 43 loose on the spindle 25 and with which engages a pawl 44 one end 46 of which is pressed into engagement with the ratchet 43 by the flexible blade 53 and the other end of which is formed as a stirrup 47 connected by the spindle 52 with a rod 49 extending through the casing and a boss 51. By pressing on the end 50 of the rod 49 the ratchet wheel 43 is released and the mechanism returns to zero under the action of the spring 42. In order to measure the lengths of arcs of circles the instrument is fitted to a limb 60 of a compass 61 by pins 58, 58<1> on the casing 1 against which can bear a support 59 secured by screws 62, and by a screw 39 passing through a recess in the limb 60 into an internally screw-threaded sleeve 37.