SU367784A1 - Auto reduction range finder - Google Patents

Description

I

The invention relates to the field of geodetic instrumentation and is intended to measure lengths without the use of auxiliary devices, rails, signals, reflectors, etc. and without the need to calculate horizontal distances from measured vertical angles and lengths of inclined lines.

From the application of the proposed invention, the productivity of surveying and geodetic surveys will increase, errors will be reduced.

The known auto-reduction devices for in-base range finders, such as the BRT-006 lens compensator manufactured by Zeis, are complex, inaccurate and spoil the image, which is especially important for binocular range finders, where image quality requirements are high. The lens compensator of the device contains, in addition to the movement mechanism, two more optical lenses. The proposed device does not introduce optical components, and the autoreduction is performed by moving one of the basic prisms already present in the device, whose dimensions are increased by the length of the movement, which does not affect the image quality and slightly increases the dimensions.

The drawing schematically shows a reduction gear for an intra-base znomera. Here: the double reflection prism 1 is attached and determines the left end of the base variable far} epa B. The right end of the rangefinder base is determined by the fixed double reflection prism 2 by the value of DB smaller than the prism 1 Reducing device consists of a fixed cam 3, mounted on a fork 4, a pusher 5 with a toothed rack 6, two gears 7 and 8 and a cam 9, In addition, the drawing shows a box of a prism 10 an emphasis 11, ball bearings 12, springs 13 and 14.

The mechanism is as follows; horizontal distance of the measured distance B; Dpgd Dcos. can be obtained from the formula

t i-B-CosoL

iJpeA p

"I i - focal distance B - base of the range finder, t - size of the distance measuring range

scales.

From this formula, it can be seen that the horizontal distance of the measured distance can be obtained with the same rangefinder scale available in the device or by changing the fsjus distance of the lens, which is very inconvenient, or by changing the size of the base.

For this purpose, one of the basic prisms of the BR-18O is fitted into a frame that allows it to be moved parallel to the base of the rangefinder according to the law:

B AB -y-C-l-CosdL),

where B is the size of the base with the horizontal position of the sighting lines;

d is the angle of inclination of the sight lines; dB - base increment depending on the change in the angle of inclination. At the same time, the moving base prism 1 is increased compared to p by prism 2 and its size is equal to

Bs

- + - b (- -CoSoL) -i-l,

L

m

object a - distance between centers

tivs;

B - the size of the base of the rangefinder, the angle of inclination (largest), D - the light diameter of the lens. The latter is very simple and reliably carried out by the proposed system. The device (function works as follows. When

turning the horizontal axis, the pusher 5 slides along the surface of the cam 3, the rack 6, coupled with the pusher, makes a forward movement at 9gg and rotates gears 7 and 8, on one of which the cam 9 is fixed, having constant point contact with the stop -ll movable prism 1, which moves in guides by the increment value of the cam radius vector. The kinematic closure is performed by the springs 13 and 14.

Formula inventions

An auto-wired range finder with a constant parallax angle and a variable oasis with an instrument in which one

from the end reflectors are made movable along the base with the help of a cam medanism, through gears connected with the horizontal axis of rotation, about the same and with the fact that

reliability and simplification of the design, the double reflection prisms of the BR - 180 were used as the end reflectors, the movable reflector is more stationary by

B

(-coscL

yb

where B is the size of the rangefinder base,

oL - the largest angle of inclination. 1n