SU1743905A1 - Geometry instrument - Google Patents

Abstract

Use: teaching devices in geometry, allows to expand the range of tasks by demonstrating the points of intersection with the body directly. Invention: when rotating ring 7, coaxially installed with the possibility of rotation in ring 6 and having diametrically mounted writing elements 8 on its inner surface describe on the volumetric body 2 the trace of the intersection of the plane with the given body at a given angle, and the points of contact of the writing elements 8 of the body 2 indicate the points of entry and exit of the direct body at its intersection with the body 2. Turning the ring 6 in the ball joints 5 installed in the telescopic pillars 4 that are movable along the base 1, set the ring 6 at the given angles relative to the body 2. 1 sludge.

Description

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The invention relates to demonstration devices and can be used, for example, when studying in a course the geometry of direct intersection phenomena with bulk bodies.

The purpose of the invention is to expand the range of tasks to be accomplished by demonstrating the points of intersection direct with the body.

The drawing shows a diagram of the device.

The device contains a base 1, a bulk body 2 placed on the base, and a means for building body intersection lines.

The means for building body intersection lines consists of 3 vertical telescopic pillars 4 placed on the base 1 with the possibility of movement, for example, by means of sliders, with spherical hinges 5 mounted on the upper ends connected with the latter and enclosing the volume body 2 of the support ring 6.

coaxially placed in the last rotary ring 7 and spring-loaded writing elements 8, placed diametrically opposite on the inner surface of the rotary ring 7 and in contact with the outer surface of the volume body 2.

The device works as follows

Before the start of the demonstration, a required three-dimensional body 2 (in this case, a cone) is installed on the base 1 so that it is placed between the pillars 4 and placed inside the rings 6 and 7.

Then, turning the ring 6 in the hinges 5, set it at a given angle to the body 2 and at the same time ensure that the body touches the writing elements 8.

The tangency points of the writing elements 8 of the body 2 will be the desired points of entry and exit direct when it intersects with the body.

To demonstrate the section of the body 2, the plane rotates the ring 7 and as a result

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The writing elements 8 will describe on the body 2 the trace of the intersection of the plane with the given body.

The use of the invention makes it possible to clearly and clearly demonstrate the phenomena of the intersection of a volumetric body by a plane and straight at predetermined angles.

Claims (1)

Claims An educational instrument in geometry, comprising a base, a volumetric body placed on the base and means for building body intersection lines, having a writing element in contact with the outer surface of the body, characterized in that in order to expand the range of tasks to be solved by demonstrating intersection points straight with the body, the means for constructing the lines of intersection of the body is provided with vertical telescopic struts with spherical hinges mounted on the upper ends, associated with the latter and supporting ring enclosing the three-dimensional body, coaxially housed in the last rotary ring and additional writing element in contact with the outer surface of the body, while the writing elements are spring-loaded and placed diametrically opposite on the inner surface of the slewing ring.