CN2309237Y - Multi-functional elliptic compasses - Google Patents

Abstract

The utility model relates to compasses for drawing ellipses, comprising a handle, compasses legs, a needle leg, a lead leg, etc. The utility model is characterized in that an arc-shaped scale is respectively fixed on the compasses legs of the elliptic compasses, and graduation lines are arranged on the scales. The scales are moved as the opening and closing of the compasses legs arranged at both sides. The elliptic compasses are provided with a line foot which is fixed in a foot changing fork hole by a top line, and a line hole and a line card are arranged on the line foot. A thin line penetrates through the line hole, and the line card is used for fixing the length of the thin line. A paint brush is arranged at the outside of the elliptic compasses, and the upper end of the lead leg of the paint brush is provided with a line groove which has the function of firmness by hooking the thin line. The multi-functional elliptic compasses has the advantages of simple operation and convenient operation.

Description

Multifunction ellipse rule

The utility model relates to a kind of drafting instrument multifunction ellipse rule.

At present, drawing ellipse is the thing that senior middle school how much teachers, student, engineers often run into, and traditional ellipse of drawing has the technique of painting how much, and fine rule is the elliptic focus technique of painting fixedly, four hearts circle picture sub-elliptical, and these method complexity, accuracys of drawing ellipse are not high.

The utility model purpose provides a kind of easy and simple to handle, draws circle drafting instrument accurately.

The utility model is finished in the following way, promptly fix an arc scale on this ellipsograph, establish graduation mark on the scale, its scale be according to same central angle the ratio of right arc mark for the definite value principle, two side mark leg lower ends are provided with changes sufficient entry, and the line foot is inserted in to change in the sufficient entry to be fixed by jackscrew.On the line foot line hole and ply-yarn drill are set, fine rule is worn cable-through hole, and its length is regulated by ply-yarn drill, and paintbrush is arranged on outside the ellipsograph, and wire casing is set on the paintbrush, can hook fine rule, makes it be difficult for slippage when trace.

This ellipsograph also can be used for picture circle, as the line foot is taken off from changing in the sufficient entry, be inserted in to change and fixed by jackscrew in the sufficient entry and change pin foot and plumbous foot, compasses.

This ellipsograph principle is simple, according to ellipse side With the eccentricity formula $e=\frac{c}{a}$ Characteristics, oval size, eccentricity, the oval center of circle are by divider calipers and fine rule control, and be easy to use, is a kind of instrument of desirable picture ellipse.

Drawings and Examples:

Fig. 1 is multifunction ellipse rule schematic diagram

Fig. 2 is a multifunction ellipse programming cutaway view

In the described multifunction ellipse rule of Fig. 1, the 1st, handle; The 2nd, fixing point; 3,4th, the rule leg; The 5th, scale; The 7th, change sufficient entry; The 8th, jackscrew; The 9th, the line foot; The 10th, the line hole; The 11st, ply-yarn drill; The 12nd, the fine rule rope.

In the paintbrush of the described multifunction ellipse rule of Fig. 2, the 13rd, penholder; The 14th, wire casing; The 15th, plumbous foot; The 16th, the pin foot.

During use, it is long to calculate transverse according to conditions such as elliptic equations, after the data such as focus, earlier line foot (9) is inserted in to change in the sufficient entry (7) and is fixed by jackscrew (8), opening the rule leg then spends at this and reads the long 2a of long axis of ellipse on chi (5), and definite fine rule (12) is long for 2a, and is with ply-yarn drill (11) that fine rule (12) is fixing; According to the elliptic focus data, angle between two rule legs (3,4) is dwindled then, make its distance equal the long 2c of elliptic focus.Two rule legs (3,4) be fixed on the elliptic focus, holding penholder (13) then hooks fine rule (12) tension with the wire casing (14) on the paintbrush (6) and slides and respectively draw half-round curve in the divider calipers both sides, promptly be drawn as a complete ellipse, change in the sufficient entry (7) as being inserted in, just can be transformed into compasses with (15) plumbous foot and (16) pin foot.

Claims (3)

1, a kind of multifunction ellipse rule, it comprises handle (1), fixing point (2) rule leg (3,4), change sufficient entry (7), jackscrew (8), it is characterized in that: fix an arc scale (5) on this ellipsograph leg, its scale label changes with two side mark leg opening and closing, and this ellipsograph is provided with line foot (9), and to be fixed on changing on the rule leg by jackscrew (8) be in the entry (7), and this ellipsograph is provided with a paintbrush (6).

2, according to the described multifunction ellipse rule of claim 1, it is characterized in that: on this line foot (9) line hole (10) and ply-yarn drill (11) are set, fine rule (12) is worn cable-through hole (10), and its length is fixing by ply-yarn drill (11).

3, according to the described multifunction ellipse of claim 1 rule, it is characterized in that: this paintbrush (6) top is penholder (13), and the lower end is provided with wire casing (14), draws when oval wire casing (14) and hooks fine rule (12) and make fine rule be difficult for slippage to play firm effect.

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