CN201998687U - Concentric compasses - Google Patents

Abstract

The utility model relates to concentric compasses for drawing. Compasses commonly used in ruler and compass construction generally comprise two compass support legs, wherein one compass support leg is provided with a compass point, and the other one compass support leg is provided with a nib. Only one circle or arc can be drawn once, and the distance between the two support legs needs to be reset when the radius of a circle to be drawn is changed. A nib support leg of the concentric compasses is shorter and connected with a rotatable nib rod, and a plurality of nibs can be mounted on the nib rod, so that the compasses can be used for simultaneously drawing a plurality of concentric circles or arcs, and are more flexible in use and wider in application range.

Description

A kind of concentric compasses

Technical field

The utility model relates to a kind of concentric compasses.

Background technology

Compasses commonly used in the construction with ruler and compasses generally include two compasses supporting legs, and one of them is equipped with the compasses point, and another is equipped with nib, once can only draw a circle or circular arc, when drawn radius of a circle changes, need reset the distance of two supporting legs.

Summary of the invention

The purpose of this utility model provides can draw a plurality of concentrically ringed concentric compasses simultaneously.

To achieve these goals, the technical solution adopted in the utility model is:

A kind of concentric compasses includes handle, junction button, needle point supporting leg, nib supporting leg, nib, needle point, screw, it is characterized in that:

The top stiff end of described needle point supporting leg and nib supporting leg is connected the both sides of junction button;

Described nib supporting leg is shorter, and its underpart is provided with pen arm, adopts the axle connected mode between nib supporting leg and the pen arm, and fixes with screw;

Described pen arm is provided with penetrating nib holddown groove, and the stiff end of some nibs is fixed on the nib holddown groove by screw.

The utlity model has following advantage:

The nib supporting leg of concentric compasses is shorter, is connected with rotating pen arm, on the pen arm a plurality of nibs can be installed, and makes compasses can draw simultaneously a plurality of concentric circles or circular arc, makes the use of compasses more flexible, and range of application is wider.

Description of drawings

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

Among the figure, 1-handle, 2-junction button, 3-needle point supporting leg, 4-nib supporting leg, 5-pen arm, 6-nib, 7-needle point, 8-screw, 9-nib holddown groove.

The specific embodiment

The utility model is described in detail with specifying below in conjunction with accompanying drawing.

The compasses that general construction with ruler and compasses uses include handle 1, junction button 2, needle point supporting leg 3, nib supporting leg 4, nib 6, needle point 7 and screw 8; Handle 1 is arranged on junction button 2 tops, and the stiff end on needle point supporting leg 3 and nib supporting leg 4 tops is connected to the both sides of junction button 2; The lower end of needle point supporting leg 3 connects needle point 7, and the lower end of nib supporting leg 4 connects nib 6, fixes with screw respectively.Draw bowlder, the distance between needle point supporting leg 3 and the nib supporting leg 4 is adjusted into the length that desire is drawn radius of a circle, needle point 7 is fixed on circle centre position, clutch handle 1 with finger, and turning handle 1, nib supporting leg 4 moves in a circle around the center of circle, and nib 6 is drawn circle and moved and finishes.

The concentric compasses that the utility model relates to, its nib supporting leg 4 is shorter, its underpart is provided with pen arm 5, adopt the axle connected mode between nib supporting leg 4 and the pen arm 5, and it is fixing with screw 8, pen arm 5 can rotate in the plane that the two coexists around the tie point between nib supporting leg 4 and the pen arm 5.Pen arm 5 is provided with penetrating nib holddown groove 9, the stiff end of some nibs 6 is fixed on the nib holddown groove 9 by screw 8, and with pen arm 5 mutual vertical fixing, the screw of nib 6 stiff ends can move along nib holddown groove 9, the distance between the nib 6 just can be regulated arbitrarily.The setting of above structure makes compasses have a plurality of nibs 6 can draw circle simultaneously simultaneously, and a plurality of concentric circles just can disposablely draw.

Claims (1)

1. a concentric compasses includes handle (1), junction button (2), needle point supporting leg (3), nib supporting leg (4), nib (6), needle point (7), screw (8), it is characterized in that:

The top stiff end of described needle point supporting leg (3) and nib supporting leg (4) is connected the both sides of junction button (2);

Described nib supporting leg (4) is shorter, and its underpart is provided with pen arm (5), adopts the axle connected mode between nib supporting leg (4) and the pen arm (5), and fixing with screw (8);

Described pen arm (5) is provided with penetrating nib holddown groove (9), and the stiff end of some nibs (6) is fixed on the nib holddown groove (9) by screw (8).

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