CN116067250A

CN116067250A - Measuring and positioning tool for circles

Info

Publication number: CN116067250A
Application number: CN202111268132.9A
Authority: CN
Inventors: 惠磊
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-10-29
Filing date: 2021-10-29
Publication date: 2023-05-05

Abstract

The invention relates to a measuring and positioning tool for a circle, which comprises a positioning unit and a measuring unit, wherein a notch is formed in the positioning unit, the notch is a V-shaped angle, the measuring unit is a first straight ruler, one end of the first straight ruler is connected with the V-shaped angle, and the first straight ruler is arranged along an angle bisector of the V-shaped angle. Compared with the prior art, the invention can measure the intersection point value of the measured circle and the ruler by utilizing the tangential line property and trigonometric function relation of the circle, and the numerical values of the radius and the circle center are determined by the proportional relation, so that the positioning on the ruler is accurate and convenient.

Description

Measuring and positioning tool for circles

Technical Field

The invention relates to the field of measuring tools, in particular to a measuring and positioning tool for a circle.

Background

In daily life, school teaching or engineering projects, it is often encountered to determine the radius and center position of a known circle. The conventional method is to find out the diameter of a circle, calculate the radius by using the diameter of the circle, and determine the position of the circle center by using the intersection point of the two intersecting diameters. Based on the principle, some circle center solving ruler, circle center positioners and the like suitable for engineering design and teaching are manufactured in the prior art, but the structure is complex, the operation difficulty is high, and the efficiency is low in actual use.

Disclosure of Invention

The object of the present invention is to overcome the above-mentioned drawbacks of the prior art by providing a measuring and positioning tool for circles.

The aim of the invention can be achieved by the following technical scheme:

the utility model provides a measurement positioning tool for circle, includes positioning unit and measuring unit, be equipped with a breach on the positioning unit, this breach is V type angle, measuring unit is first ruler, V type angle is connected to the one end of first ruler to first ruler sets up along the angular bisector of V type angle.

Further, the central axis of the first ruler is located on the angular bisector of the V-shaped angle, scales of the first ruler are distributed along the central axis, and the beginning of each scale is located at the angular tip of the V-shaped angle.

Further, two groups of scales are distributed on two sides of the central axis, wherein the scale of one group of scales is 1:1, a step of; the other set of scales is 1/(1-Sin (θ/2)): 1, θ represents the angle of the V-shaped angle.

Further, the positioning unit comprises a second ruler and a third ruler, and one side edge of the second ruler and one side edge of the third ruler are connected in an intersecting mode to form a V-shaped angle.

Furthermore, scales are distributed on the edges of the V-shaped angles, and the initial positions of the scales are located at the corner tips of the V-shaped angles.

Further, the angle of the V-shaped angle is 10-170 degrees.

Further, the angle of the V-shaped angle is 60 °.

Further, the positioning unit and the measuring unit are integrally formed.

Further, the positioning unit and the measuring unit are transparent units.

Further, a vernier is arranged on the first ruler.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention has simple operation and high use efficiency. When in use, the two sides of the V-shaped angle on the positioning unit are tangential to the circle, namely the distance a between the vertex angle of the V-shaped angle and the round edge can be read through the first ruler, then the angle theta of the V-shaped angle is combined to pass through the formula r=k×a, wherein,

and calculating to obtain the value of the radius r. Meanwhile, the first ruler is also provided with a central axis on the angle bisector, and the corresponding position of the reading of a/(1-Sin < theta/2)) on the first ruler on the central axis is the center position.

2. Two groups of scales are distributed on two sides of the central axis of the first ruler, and the scale of the first group of scales is 1:1, the scale of the second set of scales is 1/(1-Sin (θ/2)): 1, after the distance a between the top angle of the V-shaped angle and the round edge is directly read on the first group of scales, the position of the same reading on the second group of scales on the central axis is found and is the position of the circle center, and the value of the radius r is obtained by subtracting a from the degree corresponding to the position of the second group of scales on the first group of scales, so that the calculation step is simplified by setting the two groups of scales, and the operation efficiency is higher.

3. The angle theta of the V-shaped angle is preferably 60 degrees, the calculation formula can be simplified into radius r=a, and the distance a between the vertex angle of the V-shaped angle and the round edge is read out from the first ruler to be the radius r directly, so that calculation is not needed; at this time, the reading position of the first ruler, which is twice of the central axis on the angle bisector, is the center position.

4. The positioning unit of the invention can adopt two straight ruler structures, simplifies the structure and is easy to use.

5. The invention can be simultaneously applied to circular shape and circular defect with central angle larger than (90-theta/2) degrees.

Drawings

Fig. 1 is a schematic structural diagram of a first embodiment of the present invention.

Fig. 2 is a schematic diagram of the measurement principle of the present invention.

Fig. 3 is a schematic structural diagram of a second embodiment of the present invention.

Detailed Description

The invention will now be described in detail with reference to the drawings and specific examples. The present embodiment is implemented on the premise of the technical scheme of the present invention, and a detailed implementation manner and a specific operation process are given, but the protection scope of the present invention is not limited to the following examples.

Example 1

As shown in fig. 1, the present embodiment provides a measuring and positioning tool for a circle, which can directly measure the radius of a circle or a segment of the circle, and can also position the center of the circle. The measuring and positioning tool comprises a positioning unit and a measuring unit, and the whole measuring and positioning tool can be integrally made of transparent materials. The measuring unit is a first ruler 1, a notch which is a V-shaped angle is arranged on the positioning unit, one end of the first ruler 1 is connected with the V-shaped angle, and the first ruler 1 is arranged along an angle bisector of the V-shaped angle. The first ruler 1 is provided with a central axis 11, the position of the central axis 11 coincides with the angle flat line, and the scale initial position on the first ruler 1 is positioned at the angle point of the V-shaped angle. The angle of the V-shaped angle is not limited and may be generally 10 to 170 °. The specific formation of the positioning unit is not limited, and in order to simplify the structure, the positioning unit may be provided in a V-shaped structure composed of the second ruler 2 and the third ruler 3. One side edge of the second ruler 2 and one side edge of the third ruler 3 are intersected and connected to form a V-shaped angle. The intersecting edges of the second ruler 2 and the third ruler 3 are uniformly distributed with scales, and the initial positions of the scales are also positioned at the corner tips of the V-shaped corners. In other embodiments, as an optimized structure, a sliding vernier may be provided on the central axis 11 of the first ruler 1 to improve the accuracy of measurement.

The embodiment utilizes the tangential line property and trigonometric function relation of the circle, and the circle center is always on the first ruler 1 of the V-shaped angular bisector, the intersection point value of the measured circle and the first ruler 1 is measured firstly, then the numerical values of the circle center and the radius are determined through the proportional relation, and the circle center is directly positioned on the first ruler, so that the method is accurate and convenient. The specific measurement and positioning principle is as follows:

as shown in fig. 2, the V-shaped ruler (denoted DAF) is tangent to the arbitrary radius circle O (or circle segment, O point is the center of the circle/circle segment) at two points B and C. A first ruler (denoted AE) is located on the bisector of +—daf (V-angle). AE intersects circle O at point G. Thus, the calculation of GO (radius r) and AO (center position) is as follows:

is tangent to the circle O, and OB T AD can be obtained by the tangent theorem

Sin & lt DAE=OB/AO (Right-angle side-to-side bevel edge)

go=ao-AG and og=ob (the radii of the circles are equal)

Sin +.DAE=OB/AO= (AO-AG)/AO, deriving AO=AG/(1-Sin +.DAE)

AG can be directly read out by a ruler AE, namely the distance a, sin & lt DAE is half of a known V-shaped angle theta. Thus, GO (radius r) can be found from the formula go=ao-AG; meanwhile, the position of the reading AG/(1-Sin & lt DAE) is found on the first ruler to be the circle center.

As is clear from the above, in the present embodiment, when in use, only the two sides of the V-shaped angle on the positioning unit are tangential to the circle, the distance a between the vertex angle of the V-shaped angle and the circle edge can be directly read out by the first ruler, and then the angle θ of the V-shaped angle is combined with the formula r= (a/(1-Sin × (θ/2))) -a=k×a, wherein,

and calculating to obtain the value of the radius r. Meanwhile, the corresponding position of the reading of a/(1-Sin < theta/2)) on the first ruler on the central axis is the circle center position.

Example two

The basic structure of this embodiment is the same as that of the first embodiment, and the difference is that: in order to simplify the calculation in the use process, two groups of scales are distributed on two sides of the central axis 11, wherein the scale of the first group of scales is 1:1, a step of; the second set of scale bars is 1/(1-Sin (θ/2)): 1, θ represents the angle of the V-shaped angle. Therefore, after the distance a between the vertex angle of the V-shaped angle and the round edge is directly read on the first group of scales, the same reading position on the second group of scales on the central axis 11 is found to be the position of the circle center, and the value of the radius r is obtained by subtracting a from the reading b corresponding to the second group of scales on the first group of scales, only one subtraction is needed, so that the operation efficiency is higher.

In the most preferred version of this embodiment, the V-angle is selected to be 60 °. At this angle, the distance a of the near intersection point of the first ruler 1 and the circle is the radius of the circle. When the V-shaped angle is 60 degrees, the scale bar of the first group of scales is 1:1, a step of; the second set of scale bars is 2:1. the first set of scales and the second set of scales can be completely aligned, and the precision is higher. And finding out the position which is equivalent to the reading position of the first group of scales on the second group of scales, namely the position of the circle center. Calculation can thus be avoided entirely, measurement and positioning being done only by reading.

The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.

Claims

1. The utility model provides a measurement positioning tool for circle, its characterized in that includes positioning unit and measuring unit, be equipped with a breach on the positioning unit, this breach is V type angle, measuring unit is first ruler (1), V type angle is connected to one end of first ruler (1) to first ruler (1) are along the angular bisector setting of V type angle.

2. A measuring and positioning tool for a circle according to claim 1, characterized in that the central axis (11) of the first ruler (1) is located on the bisector of the V-angle, the graduations of the first ruler (1) are distributed along said central axis (11), the beginning of said graduations being located at the corner point of the V-angle.

3. A measuring and positioning tool for a circle according to claim 2, characterized in that two sets of scales are distributed on both sides of the central axis (11), wherein the scale of one set of scales is 1:1, a step of; the other set of scales is 1/(1-Sin (θ/2)): 1, θ represents the angle of the V-shaped angle.

4. A measuring and positioning tool for a circle according to claim 1, characterized in that the positioning unit comprises a second ruler (2) and a third ruler (3), one side of the second ruler (2) and one side of the third ruler (3) being connected to each other to form a V-shaped angle.

5. A measuring and locating tool for a circle according to claim 1, wherein the edges of the V-shaped angle are each provided with a scale, the starting position of the scale being located at the corner tip of the V-shaped angle.

6. A measuring and locating tool for a circle according to claim 1, wherein the angle of the V-shaped angle is 10-170 °.

7. A measuring and locating tool for a circle according to claim 1, wherein the angle of the V-shaped angle is 60 °.

8. A measuring and locating tool for a circle according to claim 1, wherein the locating unit and the measuring unit are of integrally formed construction.

9. A measuring and locating tool for a circle according to claim 1, wherein the locating unit and the measuring unit are transparent units.

10. A measuring and positioning tool for circles according to claim 1, characterised in that said first straight ruler (1) is provided with a vernier.