CN201155957Y - Curve length ruler - Google Patents

Abstract

A curve length ruler belongs to the teaching aid. The utility model provides a curve length ruler, which can conveniently and accurately measure the curve length, and thus the teaching and the use are intuitively clear. The curve length ruler comprises a bracket, and has the structural features that a measuring rope is arranged on rollers at the two ends of the bracket; a dividing ruler is arranged above the bracket.

Description

The length of curve chi

Technical field:

The utility model is to belong to teaching aid.

Background technology:

At present, the student especially measures curve (mainly being to measure two places distance on the map) length in geography and the practical activity in study, mainly be range estimation and fathom; These two kinds of method errors are all bigger, and it is very difficult that students wants to measure exact length.

The utility model content:

The utility model is exactly at the problems referred to above, and a kind of length of curve chi of measuring length of curve exactly that makes things convenient for is provided, and makes teaching, visual and understandable when using.

For achieving the above object, the utility model adopts following technical scheme, and the utility model comprises carriage, and its structural feature lining rope is arranged on the roller at carriage two ends, and the top of carriage is provided with rule.

The beneficial effects of the utility model:

When using, length of curve chi of the present utility model avoided hand to touch the accuracy that the lining rope influence is measured; On roller and lining rope, mark the measurement index line, survey, improved the accuracy of measuring from index line; Curved measurement is easily tackled, directly perceived, understandable.

Description of drawings:

Fig. 1 is a structural representation of the present utility model;

Fig. 2 is the A-A cut-open view of Fig. 1;

Fig. 3 is the B-B cut-open view of Fig. 1.

Embodiment:

The utility model comprises carriage 2, and lining rope 1 is arranged on the roller 4 at carriage 2 two ends, and the top of carriage 2 is provided with rule 3.

Below in conjunction with a description of drawings course of action of the present utility model:

When actual measurement, the starting point that the measurement index line of setting on the roller 4 is aimed at tested curve, the measurement index line of setting on the lining rope 1 is aimed at " 0 " scale mark of rule; Rotation roller 4, the terminal point along the circuit of tested curve to curve; According to the distance of roller 4 rollings and the equidistant principle of lining rope 1 slip, the red index line of lining rope 1 has just indicated tested length of a curve on rule 3.

Claims (1)

1, length of curve chi comprises carriage (2), it is characterized in that lining rope (1) is arranged on the roller (4) at carriage (2) two ends, and the top of carriage (2) is provided with rule (3).

Images