SU82799A1 - Affiliate Projection Tool - Google Patents

Description

The invention relates to apparatus for drawing affine projections made in the form of rotating lines around hinges.

In the known devices of this type, there are usually four rotary rulers articulated with hinges that carry the padding, its and the bypass spikes.

In the proposed device, in order to simplify it, two of the four rotary rulers are replaced by parallel moving rulers (by means of, for example, conventional articulated parallelograms), and at the intersection points with the rotary rulers, the writing and bypass edges are mounted.

Thanks to such a device, the structure of the device is simplified and its use is facilitated.

FIG. 1 shows a schematic of the device in plan, a general view; in fig. 2 shows the fixture of the device on the drawing table; in fig. 3 shows a section of the device but the axis of the writing and bypass tips; in fig. 4 - device installation diagram.

The principle of operation of the device is based on the affine correspondence of two planes.

Line 00 (Fig. 4) is fixed motionless on the axis of affinity, and points L and B are at related points.

The OM and ON levers have the ability to rotate around the corresponding points L and B, while their intersection point (point O) moves along the affinity axis, remaining all the time on it. MN has the ability to move parallel to itself (parallel to the direction of affinity). At the same time, points M and N always remain at the intersection of direct MN with the corresponding levers. For parallel movement of the direct AlyV, a transformer used in drawing parallelograms is used. If the point / V is moved along some line, then, based on the affine transformation properties, the point M will describe the related line.

On the drawing board, the base 2 is fastened with a clamp /, on which two levers 3 and 4 are fixed, guiding 5 and the hinge 6; lines 7 and S with their ends pivotally connected to the direction № 82799

5 and can move and rotate around the axles 9 mounted on the levers.

With the help of rollers 14 with swivel rulers 7 and 5, the transverse ruler W is connected, which has the ability to move parallel to itself with half the leverage of the drawing parallelogram //.

At the intersection of the transverse ruler with rulers 7 and 5, a bypass pin 12 and a pencil 13 are installed.

To work on the device, it is necessary to set the axes 9 at points whose coordinates are determined depending on the set parameters.

When bypassing the drawing contours with a pencil, the pencil will draw an affine or axonometric projection (depending on the installation).

To obtain a projection of a spatial body, it is necessary to have its projection with numerical marks.

The paper on which the image is drawn is fixed on the plate, which has the ability to rotate and move parallel to the subject plane. The tablet is installed at a certain angle to the axis of affinity. Bypassing each horizontal successively and at the same time moving the tablet with the image parallel to itself in the object plane by an amount corresponding to the difference between the marks of the next and previous horizontal, you can get the projections of each horizontal.

Connecting then the corresponding points, we obtain an affine or axonometric projection of a spatial body.

Subject invention

An apparatus for drawing affine projections made in the form of two rotating lines around non-moving centers of lines, connected by a hinge sliding along a guide, located along the axis of affinity, characterized in that the writing and bypass points are mounted at the intersection points of the rotating lines with a ruler moving for example, by means of hinged parallelograms of a drawing device.

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FIG.