CN2187552Y

CN2187552Y - Multi-purpose drawing compasses

Info

Publication number: CN2187552Y
Application number: CN 94205916
Authority: CN
Inventors: 杨先端
Original assignee: Individual
Current assignee: Individual
Priority date: 1994-03-26
Filing date: 1994-03-26
Publication date: 1995-01-18
Anticipated expiration: 2004-03-26

Abstract

The utility model relates to a teaching tool as well as a drawing tool used by surveying people. The utility model is composed of common compasses. A connecting shaft (4) at a hinging place of two compass legs (5) is provided with a fixed pulley (2). A thread rope (7) wound on the pulley respectively penetrates through thread pores (11) of a hollow compass leg and leg needles (13). The thread rope (7) positioned between the two leg needles at the lower ends of the compass legs is provided with a column drawing pen (9). The utility model is a convenient and practical multi-purpose drawing compass. The utility model can be used for drawing a circle, an ellipse and a hyperbola. The methods for drawing an ellipse and a hyperbola conform to definitions. The utility model is good for teachers who teach the pattern and the definition of a track, and is good for students who comprehend and memorize knowledge. The utility model is an ideal teaching tool.

Description

Multi-purpose drawing compasses

The utility model relates to the drawing tool of teaching aid and mapping worker use.

Existing garden rule can only be drawn the garden, and ellipse garden rule also can only be drawn ellipse garden, and existing multigauge can only be drawn garden and ellipse garden.

The purpose of this utility model provides the many with mapping rule of a kind of convenience, practicality, and it can draw the garden, can draw ellipse garden and hyperbola again.

The utility model takes following measure to reach: mapping rule are made of common garden rule, on the shaft coupling at the two gardens rule pin place of being hinged fixed pulley is housed, is around in cotton rope on the pulley and passes threading aperture on hollow garden rule pin and the pin pin respectively and be positioned at the garden and advise on the cotton rope between the end bipod pin of underfooting a cylindricality paintbrush is arranged.

Garden rule pin is the semiclosed garden shape pipe of hollow; An annular element that has groove and scale is arranged at two rule pin tops; An end has the threading aperture on the pin pin that the bipod lower end is screwed respectively; The outer wall of paintbrush has a ring set groove.

Fig. 1 is a structural representation of the present utility model.

Two semiclosed tubular foot rests (5) below the handle (1) are located hinged at shaft coupling (4), foot rest can rotate around the axis.Fixed pulley (2) is housed on shaft coupling, and the bipod lower end uses screw (10) to be fixed with pin pin (13) respectively, and an end of pin pin has threading aperture (11), and the other end is picture syringe needle (8), uses for the picture garden.On fixed pulley, be with cotton rope (7), respectively through the foot rest of hollow, from the threading aperture of pin pin by and link together, on the cotton rope between the bipod pin, be with a dismountable cylindricality paintbrush (9), the outer wall of cylindricality paintbrush has a ring set groove (12), cotton rope can slide in groove, also can be by the fixed by nut cotton rope on the paintbrush in groove.For making things convenient for mapping person to adjust length F1F2 between the bipod pin, fix an annular element (3) that has groove and scale a foot rest upper end, penetrate groove with adjustment screw (6) another of annular element and foot rest linked to each other, by tightening or loosening screw and regulate and control length between the pin pin

Using method: many with mapping rule when the garden of picture without cotton rope and cylindricality paintbrush, when ellipse garden of needs picture and hyperbola, again cotton rope is put on, the cylindricality paintbrush is contained on the cotton rope between the bipod pin and gets final product.

When drawing ellipse garden, pass foot rest pipe respectively from drawing doublet cord for the line pulley, behind pin pin aperture cotton rope is inserted in the groove of the paintbrush outside, line can slide in groove, selected bipod spacing, determine that the pin pin spacing is focal length F1F2, make paintbrush head P to bifocal apart from sum greater than focal length, promptly PF1+PF2＞F1F2 tightens winding pulley and makes it no longer to supply line, rope yarn on the nib P point is strained, and allows the line picture that slides in the pen sleeve wall groove.Because moving some P to two fixed point F1, F2's is definite value apart from sum, so mobile paintbrush, the track of P point motion promptly is ellipse garden.

When drawing hyperbola, coiling is identical with the ellipse garden of picture, determine behind the position of focal point F 1F2 (being focal length 2c), cotton rope is fixed in the groove of the paintbrush outside, and the tension rope yarn makes fixed distance between written P point and F1 and the F2, and P is not at the mid point of F1F2, be PF1 ≠ PF2, the tension cotton rope, rotary pulley slowly supplies line, strains written P point mapping.Because pulley be around two-wire, PF1 and PF2 change equal length simultaneously; | PF1-PF2| is a definite value, and this definite value is less than F1F2, so the movement locus that written P is ordered promptly is a hyperbola, can draw hyp one, only exchanges pin pin F1 when drawing another and the F2 position gets final product, the position of some P on the constant running rope line.

The utility model is drawn rapidly accurately, intuitive is strong, and extensive, simple in structure, the easy operation of function is a kind of desirable drawing tool; Because the ellipse garden of mapping programming, hyp method principle and its definition are in full accord, help the explanation of teacher to the trace graphics definition, also be of value to understanding and the memory of student to knowledge, also be a kind of desirable teaching aid.

Claims

1, a kind of many with mapping rule, it is made of common garden rule, it is characterized in that on the shaft coupling (4) at two gardens rule pin (5) place of being hinged fixed pulley (2) being housed, be around in cotton rope (7) on the pulley and pass threading aperture (11) on hollow garden rule pin and the pin pin (13) respectively, being positioned on the cotton rope (7) between the end bipod pin of rule underfooting, garden has a cylindricality paintbrush (9).

2, mapping rule according to claim 1 is characterized in that the semiclosed garden shape pipe of garden rule pin (5) for hollow.

3, mapping rule according to claim 1 is characterized in that an annular element (3) that has groove and scale is arranged at two rule pin tops.

4, mapping rule according to claim 1 is characterized in that the last end of pin pin (13) that the bipod lower end uses screw (10) to fix respectively has threading aperture (11).

5, mapping rule according to claim 1 is characterized in that the wall of paintbrush (9) has a ring set groove (12).