GB191437A - An improved method of recording profiles and traverses in surveying and the like and apparatus therefor - Google Patents

Abstract

191,437. Williams, J. H. Oct. 6, 1921. Road-contouring apparatus; course-recording apparatus. - To avoid the use in the field of delicate recording apparatus such as that described in Specification 168,125, a preliminary record or curve showing a trigometrical function,. such as the sine, of the angle between the contour or course and an element maintaining a fixed direction such as a pendulum or compass, is prepared in the field, and this record or curve is used to determine the movement of the first motion spindle of the main recording apparatus. Figs. 1 and 2 show apparatus for obtaining the preliminary record in road-contouring. The record paper is drawn by a drum c from a feed roller j and passes over a table e under a stylus f fixed to an arm g secured to the shaft h of a pendulum i, and the paper passes from the drum c over a roller k to a receiving roller l. The drum c is driven from a shaft d driven from the road wheels of a two-wheeled carriage carrying the apparatus. The roller l is driven through belting from the drum c by way of the roller k so as to have the same peripheral speed as the drum, one of the transmission pulleys m being fitted with a friction drive to allow slip as the roll on the roller l increases in diameter. To cbtain a considerable movement of the stylus for a small change of slope when the initial slope inconsiderable, the stylus on one or other of two additional arms g on either side of the main arm g may be used. The preliminary record having been obtained, the shaft d is geared at d<1>, Fig. 7, to the main driving shaft G of the recording apparatus, and the shaft h is geared to the pendulum shaft of this apparatus. This pendulum shaft is fitted with an arm p carrying a pointer p<1> and a handle. The shaft d is rotated by a handle d<2> while the pointer p<1> is made to follow the line of the preliminary record and the apparatus thus records a true profile of the course. Fig. 8 shows apparatus for obtaining a preliminary record in course-recording. A sphere A, secured to a shaft driven from the road wheels, drives frictionally a wheel C carried by an arm of a pendulum K pivoted at I, the axis of the pivot being in line with the centre of the sphere. The rotation of the wheel C is transmitted to light-sensitive record paper which thus has a movement proportional to the horizontal distance travelled. A compass card E mounted above this paper carries a mirror F which reflects light from a source H through an aperture in the card on to the paper.