CN210881464U

CN210881464U - Triangular compasses

Info

Publication number: CN210881464U
Application number: CN201920212408.3U
Authority: CN
Inventors: 萧淑芬
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-02-19
Filing date: 2019-02-19
Publication date: 2020-06-30
Anticipated expiration: 2029-02-19

Abstract

The utility model provides a set square, including a scale carousel and an at least pointer, the periphery of scale carousel is provided with a first angle scale, the centre of a circle department of scale carousel is provided with a recess, the pointer is a ruler that has the scale, the one end that the pointer corresponds zero scale can be gone into in the recess, and can for the scale carousel is rotatory, the length of pointer is greater than the radius of scale carousel, the zero scale of pointer with the centre of a circle coincidence of scale carousel. The utility model has the advantages of, utilize the triangle gauge can conveniently draw the triangle-shaped of arbitrary angle and length of a side and not the circular of equidimension. The tool can greatly accelerate the drawing speed of students and is substantially helpful in teaching topics such as the properties of triangles or circles.

Description

Triangular compasses

Technical Field

The utility model relates to a mapping instrument field especially relates to a set square.

Background

In stationery on the market, a set square and a protractor can be used for drawing a triangle, compasses can be used for drawing a circle, and no stationery can be used for drawing the triangle and the circle. Therefore, there is a need for a new drawing tool that can draw both triangles and circles.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a triangular gauge is provided.

In order to solve the problem, the utility model provides a set square, including a scale carousel and an at least pointer, the periphery of scale carousel is provided with a first angle scale, the centre of a circle department of scale carousel is provided with a recess, the pointer is a ruler that has the scale, the one end that the pointer corresponds zero scale can be gone into in the recess, and can for the scale carousel is rotatory, the length of pointer is greater than the radius of scale carousel, the zero scale of pointer with the centre of a circle coincidence of scale carousel.

In one embodiment, the first angle scale has scale values, and the scale values are symmetrically arranged.

In an embodiment, a second angle scale is arranged on the inner side of the first angle scale, each scale of the first angle scale is 1 degree, each scale of the second angle scale is 2 degrees, the second angle scale has scale values, the scale values are symmetrically arranged, and the scale value of the first angle scale is twice the scale value of the second angle scale.

In an embodiment, the scale dial includes an annular peripheral frame and a plurality of supporting frames, the supporting frames are disposed inside the peripheral frame, one end of each supporting frame is connected to a center of the scale dial, the other end of each supporting frame is connected to the peripheral frame, the first angle scale is disposed on the peripheral frame, and the connecting positions of the supporting frames are recessed to form the grooves.

In one embodiment, the triangular gauge comprises a first pointer and a second pointer, the first pointer and the second pointer are alternatively connected to the scale rotating disc, and the second pointer is provided with holes arranged at intervals along the length direction of the second pointer.

In one embodiment, one end of the pointer corresponding to the minimum scale is provided with a protrusion, and the protrusion is clamped in the groove and can rotate relative to the scale turntable.

In one embodiment, the protrusion has a circular or arc-shaped configuration.

The utility model has the advantages of, utilize the triangle gauge can conveniently draw the triangle-shaped of arbitrary angle and length of a side and not the circular of equidimension, a stationery dual purpose, this instrument will accelerate the student greatly and draw the picture speed, has substantial help in the subject such as the nature of professor triangle-shaped or circle.

Drawings

FIG. 1 is a schematic diagram of a triangular gauge of the present invention;

FIG. 2 is a schematic structural view of the triangular gauge of the present invention;

FIG. 3 is a schematic structural diagram of the scale dial;

FIG. 4 is a schematic structural diagram of the pointer;

FIG. 5 is a schematic view of the back of the first pointer;

fig. 6A to 6D are schematic views of example 1 of a method for drawing a figure using the triangular compasses of the present invention;

FIG. 7 is a schematic view of example 2 of a method for drawing a figure using the triangular compasses of the present invention;

FIG. 8 is a schematic view of example 3 of a method for drawing a figure using the triangular compasses of the present invention;

fig. 9 is a schematic diagram of example 4 of a method for drawing a figure using the triangular compasses of the present invention.

Detailed Description

The following describes in detail a specific embodiment of the triangular compasses provided by the present invention with reference to the accompanying drawings.

First, the design principle of the triangular gauge of the present invention will be explained.

An arbitrary triangle has a different heart, see table 1.

TABLE 1 definition of the different centers of triangles

The outer center of the triangle is the intersection point of the perpendicular bisectors of the three sides, and the intersection point is also the center of a circle circumscribed by the triangle. We have found that the central angle of this circumscribed circle has a certain relationship to the internal angle of the triangle. Referring to fig. 1, three vertices of a triangle are connected to form a triangle, and the center of the triangle is also the outer center of the triangle. Starting from two points on the circumference, the angle connecting the circle centers is a central angle, and the angle connecting the circumference is a circumferential angle. The following calculation shows the relationship between the central angle and the circumferential angle.

Since AD AC AE ∠ CDA ∠ DCA a, a is the base angle of the isosceles triangle, ∠

DAF

2a, 2a is the outer angle of the triangle, similarly ∠ FAE 2b, ∠ DAE 2a +2b 2(a + b) 2 ∠ DCE, i.e. ∠ DAE 2 ∠ DCE, where AD, AC, AE are the radii, the following conclusions are reached:

central angle is 2 times of circumference angle

By utilizing the relation, the problem that two inner angles of the drawing triangle are transferred to drawing 2 central angles along the outer center of the triangle can be solved.

Fig. 2 is a schematic structural view of the triangular gauge of the present invention. Referring to fig. 2, the triangular compass of the present invention includes a scale plate 1 and at least one pointer 2. Wherein, the pointer 2 includes but is not limited to transparent or semi-transparent or opaque material. In the present embodiment, the pointer 2 is rendered opaque. The scale dial 1 is used for providing an angle reference, and the pointer 2 is used for providing a length reference.

Fig. 3 is a schematic structural diagram of the scale dial. Referring to fig. 2 and 3, a first angle scale 10 is disposed on the periphery of the scale dial 1 for marking the radian. In this embodiment, the first angle scale has scale values, and the scale values are symmetrically arranged. Specifically, the scale dial 1 is defined as 0 scale, the scale value of the first angle scale 10 is from 0 scale to 180 degrees clockwise, and the counterclockwise is from 0 scale to 180 degrees.

Further, in the present embodiment, a second angle scale 11 is disposed inside the first angle scale 10. The second angle scale 11 has scale values, which are symmetrically arranged. Every scale of first angle scale 10 is 1 degree, every scale of second angle scale 11 is 2 degrees, the scale numerical value of first angle scale 10 is twice that of second angle scale 11. Specifically, the scale dial 1 is defined as 0 scale, the scale value of the second angle scale 11 is from 0 scale to 90 degrees clockwise, and the counterclockwise is from 0 scale to 90 degrees. It should be noted that the actual radian of the second angle scale 11 is the same as the actual radian of the first angle scale 10, and only the numerical value of the second angle scale 11 is reduced by half on the externally displayed scale numerical value. It lies in that its effect is in the utility model discloses in, utilize the circumference angle to be the angle that triangle-shaped was drawn to this half principle of central angle, that is to say, if draw the angle of 30 degrees, then regard this 30 degrees as the circumference angle, the user need convert this circumference angle into the central angle, convert into 60 degrees promptly, also be exactly the actual angle of drawing on scale carousel 1, this makes the drawing not directly perceived, and the utility model discloses with the angle that second angle scale 11 direct marker was circumferential angle, the user of being convenient for is directly perceived to select.

The circle center of the scale turntable 1 is provided with a groove 13. The groove 13 is recessed on the back of the scale turntable 1. Which allows pointer 2 to snap in.

Further, in the present embodiment, the scale dial 1 includes an annular peripheral frame 14 and a plurality of supporting frames 15. The support frame 15 is arranged inside the peripheral frame 14, one end of the support frame 15 is connected at the center of the scale turntable 1, and the other end of the support frame 15 is connected to the peripheral frame 14. The first angle scale 10 is arranged on the peripheral frame 14, and the connecting positions of the plurality of supporting frames 15 are recessed to form the grooves 13. In this embodiment, a plurality of the supporting frames 15 are symmetrically disposed. A plurality of the supporting frames 15 form a plurality of gaps 16 therebetween, and the gaps 16 provide spaces for drawing a small radius circle or triangle.

Fig. 4 is a schematic structural diagram of the pointer. Referring to fig. 2 and fig. 4, in the present embodiment, the pointer 2 includes a first pointer 20 and a second pointer 21. The first pointer 20 and the second pointer 21 have different structures.

Specifically, the first pointer 20 is a ruler with scales, and one end of the first pointer 20 corresponding to the zero scale can be clamped in the groove 13 and can rotate relative to the scale dial 1. The length of the first pointer 20 is greater than the radius of the scale dial 1, for example, the radius of the scale dial 1 is 6 cm, and the length of the first pointer 20 is 15 cm. When the first pointer 20 is installed on the scale turntable, the zero scale of the first pointer 20 coincides with the center of the scale turntable 1. The second pointer 21 is a ruler with scales, and one end of the second pointer 21 corresponding to the minimum scale can be clamped into the groove 13 and can rotate relative to the scale turntable 1. The length of the second pointer 21 is greater than the radius of the scale dial 1, for example, the radius of the scale dial 1 is 6 cm, and the length of the first pointer 20 is 15 cm. The second pointer 21 has holes 22 spaced along the length of the second pointer 21, for example, in this embodiment, the holes 22 are spaced 1 cm apart. The holes 22 may be used to draw circles of different radii. When the second pointer 21 is installed on the scale turntable, the zero scale of the second pointer 21 coincides with the center of the circle of the scale turntable 1.

The first pointer 20 and the second pointer 21 are replaceably connected to the scale dial 1. Specifically, the first pointer 20 or the second pointer 21 may be selectively used according to the difference in the graphic to be drawn. Further, the pointer 2 has a protrusion 23 at an end corresponding to the minimum scale. Fig. 5 is a schematic rear view of the first pointer 20. Referring to fig. 5, a protrusion 23 is disposed at an end of the first pointer 20 corresponding to the minimum scale. The shape of the protrusion 23 includes, but is not limited to, a circle or an arc, wherein an arc is preferred to reduce friction generated with the scale dial 1 when the first pointer 20 rotates. The projection 23 snaps into the recess 13 and can rotate relative to the dial 1.

The utility model discloses the set square when drawing the figure, with the end of handing over of needs is selected for the reference to the scale on the scale carousel, rotates pointer 2, and according to the length that needs is selected to pointer 2's scale to draw corresponding circular or triangle-shaped. Utilize the utility model discloses triangle gauge can conveniently draw the triangle-shaped of arbitrary angle and length of a side and not the circular of equidimension, and this instrument will accelerate the student greatly and draw the picture speed, has substantial help in the subjects such as the nature of professor triangle-shaped or circle.

The utility model discloses still provide an adopt second pointer 21 draws circular method. Specifically, the second pointer 21 is connected to the scale dial 1, and the zero scale point of the second pointer 21 coincides with the center of the scale dial; placing a drawing pen in the hole 22 corresponding to the length of the radius of the drawn circle; the drawing pen is rotated to drive the second pointer 21 to rotate, so as to form a closed circle.

The utility model also provides a method for adopting foretell set square to draw triangle-shaped. Specifically, the principle that the central angle is equal to 2 times of the circumference angle is utilized to transfer the inner angle of the drawing triangle into the drawing of the central angle along the outer center of the triangle, wherein the angle of the central angle is measured by a scale turntable of the triangular gauge, and the length of the side length of the triangle is measured by a pointer of the triangular gauge.

The following is an example of using the triangular compasses of the present invention to draw triangles.

Example 1

Drawing a triangle with known three angles:

when the user draws a triangle with known three angles, the following steps can be performed.

Referring to fig. 6A, a set square is placed on paper, a pointer 2 is placed on the 0 scale, and a point is marked on the 0 scale with a pen.

Referring to fig. 6B, another point is marked in the clockwise direction at the degree you want;

referring to FIG. 6C, a point is marked counterclockwise at the second desired degree of you.

Referring to FIG. 6D, the triangle gauge is taken away, and the three points are connected together by a ruler, and the degrees of the three points are listed finally.

With a length of the mark on the pointer 2, we can draw similar triangles of different sizes but the same shape.

Example 2

Drawing a triangle with two corners and one side (the side length is a clamping side):

when a user draws a triangle with two known corners and one side (the side length is a clamping side), the following steps can be performed.

Referring to fig. 7, a segment with a length a is drawn by the pointer 2, and two end points a and B are marked; the circle center of the triangular gauge is arranged on A, the scale mark 0 is overlapped with AB, the pointer 2 is twisted off by the required angle, and the marking and the connection are carried out; and then the circle center is arranged on the B, the pointer 2 is twisted off by the required angle, and is marked and connected, and the intersection point (vertex C) of the two lines is the third intersection point of the triangle.

Example 3

Drawing a triangle with two corners and one side (the side length is a non-clamping side):

when a user draws a triangle with two known corners and one side (the side length is not a clamping side), the following steps can be performed.

Referring to fig. 8, knowing the angles α and β, the user can use the triangle drawing method of example 2 to draw a graph after obtaining ∠ CBA by simply using the triangle inner angle sum to obtain ∠ CBA.

Example 4

Drawing a triangle with known two corners (the angle is the included angle):

when a user draws a triangle with a known angle between two sides (the angle is an included angle), the following steps can be performed, please refer to fig. 9.

(1) The triangular gauge was placed on the paper. One point is positioned on the circle center, namely a vertex A;

(2) pointer 2 is zeroed. Then, the required length is clicked, namely the vertex B is clicked;

(3) the desired angle is twisted off. And connecting three points at one point with proper length, namely the vertex C, thereby completing the drawing.

Example 5

Drawing a triangle with known two corners (the angle is not included angle):

in case of providing two corners (the angle is not included), it is possible to form one triangle or two triangles, or even not a triangle. When we use two sides and one non-included angle, four cases are possible, as shown in table 2.

TABLE 2 several cases when drawing a triangle with two known sides and one corner (the angle is not included)

Therefore, when students draw triangles with different conditions, students can know the conditions needed for forming the triangles better, and also know that the students can not draw the triangles sometimes under insufficient conditions, and even some conditions can not form a triangle successfully at all.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The utility model provides a set square, its characterized in that includes a scale carousel and an at least pointer, the periphery of scale carousel is provided with a first angle scale, the centre of a circle department of scale carousel is provided with a recess, the pointer is a ruler that has the scale, the one end that the pointer corresponds zero scale can be gone into in the recess, and can for the scale carousel is rotatory, the length of pointer is greater than the radius of scale carousel, the zero scale of pointer with the centre of a circle coincidence of scale carousel.

2. The triangular rule of claim 1, wherein the first angle scale has scale values, the scale values being symmetrically disposed.

3. The triangular rule according to claim 2, wherein a second angle scale is provided at an inner side of the first angle scale, each scale of the first angle scale is 1 degree, each scale of the second angle scale is 2 degrees, the second angle scale has scale values, the scale values are symmetrically arranged, and the scale value of the first angle scale is twice as large as the scale value of the second angle scale.

4. The triangular rule according to claim 1, wherein the scale dial comprises an annular peripheral frame and a plurality of supporting frames, the supporting frames are arranged inside the peripheral frame, one ends of the supporting frames are connected at the center of the scale dial, the other ends of the supporting frames are connected to the peripheral frame, the first angle scale is arranged on the peripheral frame, and the connecting positions of the supporting frames are recessed to form the grooves.

5. The triangular gauge according to claim 1, comprising a first pointer and a second pointer, the first pointer and the second pointer being replaceably connected to the scale dial, the second pointer having holes spaced along a length of the second pointer.

6. The triangular rule according to claim 1, wherein one end of the pointer corresponding to the smallest scale has a protrusion, and the protrusion is snapped into the groove and can rotate relative to the scale dial.

7. The triangular rule of claim 6, wherein the protrusion is a rounded or curved structure.