CN204202543U

CN204202543U - Composite angle protractor

Info

Publication number: CN204202543U
Application number: CN201420664084.4U
Authority: CN
Inventors: 相龙海
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-11-10
Filing date: 2014-11-10
Publication date: 2015-03-11
Anticipated expiration: 2024-11-10

Abstract

A kind of composite angle protractor, comprising: protractor, protractor is semi-circular structure, protractor comprises reference line, central point and angle index, reference line is arranged at the straight line portion of protractor, and angle index is positioned at the circular arc portion of protractor, and central point is positioned at the mid point of reference line.Gage beam, gage beam comprises first connecting rod and second connecting rod, first connecting rod head end is rotationally connected with central point, tail end is movably set on second connecting rod, second connecting rod is provided with away from the end of first connecting rod the through hole holding chalk, first connecting rod and second connecting rod are arranged with one heart, and the tie point of first connecting rod and central point and through hole are all positioned on the center line of gage beam, and the center line of gage beam is provided with angulation line.Combinations thereof angle gage structure is simple, and angulation is convenient, achieves angulation simultaneously and draws round function, and when carrying, can be accommodated in first connecting rod by second connecting rod, save space, be easy to carry.

Description

Composite angle protractor

Technical field

The utility model relates to teaching apparatus for mathematics, particularly relates to composite angle protractor.

Background technology

Traditional protractor is provided with reference line, central point and angle index.Time in use, reference line and measured angle limit need be overlapped, the central point of protractor overlaps with the summit of measured angle, reads the angle index reading of another limit corresponding amount hornwork of measured angle.When the length of side for reading angular of measured angle is shorter, through the angle index region of protractor, cannot only have and extended on this limit, just can measure the angle of measured angle relatively accurately, measuring process is loaded down with trivial details time-consuming.And traditional protractor can not be used for picture circle, therefore teaching process often needs carrying amount hornwork and compasses simultaneously, carries very inconvenience.

Utility model content

Based on this, be necessary for the loaded down with trivial details time-consuming problem can not drawing round of traditional protractor problem measuring process, provide a kind of angulation convenient and may be used for the round composite angle protractor of picture.

A kind of composite angle protractor, comprising:

Protractor, protractor is semi-circular structure, and protractor comprises reference line, central point and angle index, and reference line is arranged at the straight line portion of protractor, and angle index is positioned at the circular arc portion of protractor, and central point is positioned at the mid point of reference line.

Gage beam, gage beam comprises first connecting rod and second connecting rod, first connecting rod head end is rotationally connected with central point, tail end is movably set on second connecting rod, second connecting rod is provided with away from the end of first connecting rod the through hole holding chalk, first connecting rod and second connecting rod are arranged with one heart, and the tie point of first connecting rod and central point and through hole are all positioned on the center line of gage beam, and the center line of gage beam is provided with angulation line.

Further, the quantity of through hole is multiple.

Further, the bottom surface of aperture from the surface of second connecting rod to second connecting rod of through hole reduces gradually.

Further, reference line is provided with length scale.

Combinations thereof protractor, when taking measurement of an angle, if the both sides of measured angle are all longer, can directly use protractor survey measurements.When measured angle wherein on one side short, by the reference line of protractor with measured angle while overlap, the central point of protractor overlaps with the summit of measured angle, overlapped with measured angle another side by the angulation line of gage beam, namely read volume linea angulata obtains the angle of measured angle through the reading that angle index is corresponding simultaneously.Without the need to extending the comparatively minor face of measured angle, simple to operate, accuracy of reading.At picture bowlder, fixed by protractor, be loaded in through hole by chalk and contact with blackboard, gage beam is centrally put and is rotated a circle, and can draw a regular circle, adjusts the relative position of first connecting rod and second connecting rod, can draw the circle of different size.Combinations thereof angle gage structure is simple, and angulation is convenient, achieves angulation simultaneously and draws round function, and when carrying, can be accommodated in first connecting rod by second connecting rod, save space, be easy to carry.

Accompanying drawing explanation

Fig. 1 is the structural representation of the composite angle protractor of an embodiment;

Fig. 2 is the structural representation of the second connecting rod of an embodiment.

Description of reference numerals: 100, protractor; 110, reference line; 120, central point; 130, angle index; 200, gage beam; 210, first connecting rod; 220, second connecting rod; 230, through hole; 240, angulation line.

Embodiment

A kind of composite angle protractor, as shown in Figure 1, comprise: protractor 100, protractor 100 is semi-circular structure, protractor 100 comprises reference line 110, central point 120 and angle index 130, reference line 110 is arranged at the straight line portion of protractor 100, and angle index 130 is positioned at the circular arc portion of protractor 100, and central point 120 is positioned at the mid point of reference line 110.Gage beam 200, gage beam 200 comprises first connecting rod 210 and second connecting rod 220, first connecting rod 210 head end is rotationally connected with central point 120, tail end is movably set on second connecting rod 220, second connecting rod 220 is provided with away from the end of first connecting rod 210 through hole 230 holding chalk, first connecting rod 210 and second connecting rod 220 are arranged with one heart, and tie point and the through hole 230 of first connecting rod 210 and central point 120 are all positioned on the center line of gage beam 200, and the center line of gage beam 200 is provided with angulation line 240.

Composite angle protractor is preferably and adopts transparent plastic to obtain, so that by the reference line 110 of protractor 100 with measured angle while overlap, the central point 120 of protractor 100 overlaps with the summit of measured angle, is overlapped by the angulation line 240 of gage beam 200 with measured angle another side simultaneously.Because gage beam 200 itself has certain width, if directly take measurement of an angle with it, can cause read untrue, set amount linea angulata 240 can overlap with the length of side of measured angle preferably, reduces error.Be appreciated that slotted line can for being engraved on the straight line on gage beam 200, the narrower groove also can offered for centrally line, all can realize the function overlapped with the length of side of measured angle.First connecting rod 210 is flexibly connected with second connecting rod 220, the length of adjustment second connecting rod 220 in first connecting rod 210, the i.e. distance of adjustable through hole 230 distance center point 120, i.e. adjustable radius of a circle.And when carrying, second connecting rod 220 can be accommodated in first connecting rod 210, save space, be easy to carry.

Combinations thereof protractor, when taking measurement of an angle, if the both sides of measured angle are all longer, directly can use protractor 100 survey measurements.When measured angle wherein on one side short, by the reference line 110 of protractor 100 with measured angle while overlap, the central point 120 of protractor 100 overlaps with the summit of measured angle, overlapped with measured angle another side by the angulation line 240 of gage beam 200, namely read volume linea angulata 240 obtains the angle of measured angle through the reading of angle index 130 correspondence simultaneously.Without the need to extending the comparatively minor face of measured angle, simple to operate, accuracy of reading.At picture bowlder, protractor 100 is fixed, chalk is loaded in through hole 230 and contacts with blackboard, gage beam 200 centrally 120 rotates a circle, can draw a regular circle, the relative position of adjustment first connecting rod 210 and second connecting rod 220, can draw the circle of different size.Combinations thereof angle gage structure is simple, and angulation is convenient, achieves angulation simultaneously and draws round function, being easy to carry.

Further, the quantity of through hole 230 is multiple.The distance of through hole 230 distance center point 120 is radius of a circle, arranges multiple through hole 230, and the circle of different radii not etc., also can not drawn in the position of through hole 230 distance center point 120.

Further, as shown in Figure 2, the bottom surface of aperture from the surface of second connecting rod 220 to second connecting rod 220 of through hole 230 reduces gradually.Second connecting rod 220 is bottom surface apart from the face of the close together of blackboard, and opposing face is surface.Chalk is generally frustum cone structure, and the aperture of through hole 230 reduces, and can form good cooperation with chalk.

Further, reference line 110 is provided with length scale.Length scale can make protractor 100 for measuring the length of certain length straight line.

Claims

1. a composite angle protractor, is characterized in that, comprising:

Protractor, described protractor is semi-circular structure, and described protractor comprises reference line, central point and angle index, and described reference line is arranged at the straight line portion of described protractor, described angle index is positioned at the circular arc portion of described protractor, and described central point is positioned at the mid point of described reference line;

Gage beam, described gage beam comprises first connecting rod and second connecting rod, described first connecting rod head end is rotationally connected with described central point, tail end is movably set on described second connecting rod, described second connecting rod is provided with away from the end of described first connecting rod the through hole holding chalk, described first connecting rod and described second connecting rod are arranged with one heart, and the tie point of described first connecting rod and described central point and described through hole are all positioned on the center line of described gage beam, and the center line of described gage beam is provided with angulation line.

2. composite angle protractor according to claim 1, is characterized in that, the quantity of described through hole is multiple.

3. composite angle protractor according to claim 1, is characterized in that, the bottom surface from the surface of described second connecting rod to described second connecting rod, the aperture of described through hole reduces gradually.

4. the composite angle protractor according to any one of claim 1 ~ 3, is characterized in that, described reference line is provided with length scale.