Ruler for drawing symmetric figure

Abstract

The invention relates to a ruler for drawing a symmetric figure. A left slide rail and a right slide rail are arranged on a main ruler; a slide block penetrates through the left slide rail and the right slide rail and slides on the main ruler; a gearbox base and a gearbox cover are arranged above the slide block; the lower end of the gearbox box penetrates through the slide block and is connected with a rotary sheet; a gear, a gear rack A and a gear rack B are arranged in a gearbox; rotary shafts penetrate through the gear, the gear rack A and the gear rack B; two grooves are formed in the upper surface of the main ruler; brush inserting holes are respectively formed in one side of each of the gear rack A and the gear rack B; strip holes are respectively formed in the centers of the gear rack A and the gear rack B; the rotary shafts at the two sides penetrate through the strip holes; a gap groove is formed in the main ruler, is aligned with a symmetric shaft, and is pressed and fixed by a hand; brushes are inserted into the brush inserting holes in the tail ends of the gear rack A and the gear rack B; the gear rack at one side horizontally moves to drive the gear rack at the other side to move, and the brushes horizontally move to drive the gear rack A and the gear rack B to horizontally move, and move up and down to drive the slide block to move up and down. The ruler has the advantages that the structure is simple and reasonable, and the drawing efficiency is high, and the practicality is high.

Description

technical field [0001] The invention relates to a ruler, in particular to a ruler capable of drawing symmetrical figures. Background technique [0002] In the process of our drawing, we often need to draw some axisymmetric graphics. Usually, we use simple drawing tools such as rulers and compasses to roughly draw axisymmetric graphics. There will be large errors, and it is difficult to accurately The accuracy of drawing axisymmetric graphics is largely determined by the hand-drawing ability. When it is necessary to draw a precise symmetrical figure, you can also make half of the axisymmetric figure template for rubbing, or draw half of the axisymmetric figure first, then fold the paper in half along the axis of symmetry, and use the half drawn first The graphic is copied to the other side and combined into a symmetrical graphic, but the use of these two methods has virtually affected the drawing efficiency, and the process is cumbersome and has some damage to the paper. C...

AI Technical Summary

Problems solved by technology

[0002] In the process of our drawing, we often need to draw some axisymmetric graphics. Usually, we use simple drawing tools such as rulers and compasses to roughly draw axisymmetric graphics. There will be large errors, and it is difficult to accurately Draw axisymmetric graphics, the accuracy of which is largely determined by the ability to draw

When it is necessary to draw a precise symmetrical figure, you can also make half of the axisymmetric figure template for rubbing first, or draw half of the axisymmetric figure first, then fold the paper in half along the axis of symmetry, and use the first half drawn The graphic is copied to the other side and combined into a symmetrical graphic. However, the efficiency of drawing is affected by these two methods. The process is cumbersome and damages the paper surface to a certain extent.

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