Ruler with easy-to-pick angle

Abstract

The utility model discloses a ruler with an easy-to-pick angle. The easy-to-pick angle is formed by arranging a slope surface at the corner of the edge of the back of the ruler. The slope surface intersects with the back surface of the ruler and two side surfaces at the corner, the slope surface and the back surface intersect at a line segment or a smooth curve, and the slope surface and the vertical edge at the corner intersect at one point; the projection of the slope on the back of the ruler is triangular. Compared with the mode that a slope surface and an easy-to-pick angle are arranged on a long edge, interference to a main working area is avoided, a tilting lever is lengthened, the tilting effect is remarkably improved, the easy-to-pick property of the ruler is enhanced, and cutting caused by the slope surface is reduced.

Description

[Technical field]

[0001] The invention is an improvement on the easy-to-pick-up performance of a ruler and belongs to the technical field of surveying and mapping tools. [Background technology]

[0002] Rulers are generally thin plates, usually with thinner edges, which makes them difficult to pick up from the work surface. To improve the pick-up of rulers, market products reflect two types of solutions: most of them try to break through the flatness of the ruler. Among them, the Czech KOH-I-NOOR multi-function triangle ruler and the German STAEDTLER 568 drawing ruler have convex shapes on them to facilitate lifting. Figure 3 Angle plate, KACO's RUMA metal bookmark ruler; and WHITE DESIGN's TWIST / TRIANGLE / CUBE aluminum alloy ruler that makes the ruler three-dimensional. Another solution is to make a slope on the edge of the back of the ruler, and to lift the ruler by pressing down. This solution does not require accessories and has a simple process. Currently, only the Deli 79759 Justice League ruler is used. However, this ruler has a defect: because the slope is set along the long side of the ruler (the projection of the slope on the back is a rectangle), and the long side is often the main working area of ​​the ruler, pressing during work will lift the ruler, which will interfere with the work. The present invention is an improvement on this defect. [Summary of the invention]

[0003] The invention provides a slope at the corner of the back edge of the ruler. The projection of the slope on the back of the ruler is a triangle. The corner with the slope is called an easy-to-pick-up angle. The slope intersects with the back of the ruler in a straight line, which is called the initial fulcrum line. The slope intersects with the vertical edge of the ruler at the corner at a point called the top of the slope ( Figure 1 ); the projection point of the top of the slope on the back is called the bottom point; the distance between the top of the slope and the bottom point is called the drop ( Figure 2 ); when the ruler is tilted, the point on the back of the ruler that is farthest from the working plane is called the tilt point; when the top of the slope falls to the working plane (that is, the top of the slope coincides with the bottom point), the height of the tilt point from the working plane is called the tilt height ( Figure 3 ); the line connecting the bottom point and the tilt point is called the lever line. For a rectangular ruler, the lever line is the diagonal of the rectangle on the back; the intersection of the lever line and the initial fulcrum line is called the fulcrum; the ratio of the distance from the tilt point to the fulcrum to the distance from the bottom point to the fulcrum is called the lever ratio; a perpendicular line to the initial fulcrum line is drawn on the back through the fulcrum, and the ratio of the distances from the projections of the tilt point and the bottom point on the perpendicular line to the fulcrum is equal to the lever ratio; the ratio of the tilt height to the drop is equal to the lever ratio; the ratio of the height change between the top of the slope and the tilt point is always equal to the lever ratio.

[0004] The slope surface can be a flat surface or a smooth curved surface. When the slope surface is a flat surface, the initial fulcrum line is the fixed support during the warping process, that is, the ratio of the height change of the warping point to the top of the slope during the warping process is fixed. When the slope surface is a curved surface, during the warping process, the curved surface and the working surface are tangent to a straight line or a point, which is called the variable fulcrum line or variable fulcrum ( Figure 2 -b). Because the support position changes during the tilting process, the ratio of the height change between the tilting point and the top of the slope changes, which will cause a different downward pressure feel from the flat slope, although the final tilt height and drop ratio is still equal to the lever ratio. When the curved surface is part of a cylinder, the variable fulcrum line remains parallel to the initial fulcrum line. When the curved surface is tangent to the working plane at one point, such as a sphere, although it is unstable, the direction of the ruler can be easily rotated.

[0005] Beneficial effect: Arranging the slope at the corner of the back edge of the ruler can, on the one hand, avoid the interference of the picking mechanism on the work and maintain the stability of the ruler during work; on the other hand, compared with the arrangement along the long side, the picking angle can obtain a longer lever line and a larger lever ratio. The effect of increasing the height or reducing the drop by using this enhancement effect is more significant.

Brief Description of the Drawings

[0006] Figure 1 .Easy to pick up corner plan

[0007] 1-slope top, 2-slope surface, 3-initial support line, 4-tilt point, 5-pre-selected line segment

[0008] Figure 2 . A partial enlarged view of the slope surface in the cross section of the vertical initial support line at the top of the slope (a) The slope surface is a flat surface, (b) The slope surface is a smooth curved surface

[0009] 6- the back of the ruler, 7- the working plane of the ruler, 8- the slope difference

[0010] Figure 3 . Diagram of pressing the easy-pick corner to lift the ruler

[0011] 9-Tilt height [Specific implementation method]

[0012] In order to make the purpose, scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain rather than to limit the present invention.

[0013] Take a ruler with a 10cm range and an outline size of 120x30x2mm as an example. Its diagonal line (about 123.7mm) is the lever line. Assuming that the bottom point is 4mm away from the fulcrum, the lever ratio is about 30:1 ((123.7-4) / 4), that is, when the drop is 0.4mm, the warp height is 12mm (0.4x30). If the slope is arranged along the long side, the lever line is the ruler width (30mm), which is the shortest of the line segments on the different edges of the upper end point on the back. Under the same conditions, the lever ratio is 6.5:1 ((30-4) / 4). A drop of 0.4mm can only lift 2.6mm (0.4x6.5). To lift 12mm, a drop of 1.8mm (12 / 6.5) is required. It can be seen that after the slope was changed from a long side to a corner, the leverage effect was enhanced by 4.6 times (=30 / 6.5=12 / 2.6=1.8 / 0.4), and the effect was significant.

Claims

1. A ruler with an easy-to-pick-up corner, the ruler can be tilted by pressing the easy-to-pick-up corner, characterized in that A slope is set at the edge corner of the back of the ruler, and the slope can be a plane or a smooth convex surface; the slope intersects with the back of the ruler and the two side surfaces at the corner, the slope intersects with the back in a line segment or a smooth curve, and intersects with the vertical edge at the corner at a point; the projection of the slope on the back of the ruler is a triangle.

Images