Ellipse

Abstract

The invention discloses elliptic trammels which comprise a handheld plate, an angle swing rod, a rotary shaft, a rotary sleeve and a drawing pen assembly. The drawing pen assembly comprises a drawing pen, a drawing pen locking hole, a chalk clamping hole, a chalk clamping lock and a rotary block, the rotary block is welded on the drawing pen locking hole, one end of the drawing pen is sleeved in the drawing pen locking hole, the other end of the drawing pen is fixedly connected with the chalk clamping hole, and the chalk clamping lock is matched with the chalk clamping hole; the angle swing rod is inverted-L-shaped, one end of the angle swing rod is movably connected with the handheld plate, a rotary shaft fixing sleeve is arranged at the other end of the angle swing rod, one end of the rotary shaft is fixed into the rotary shaft fixing sleeve, the rotary sleeve is sleeved at the other end of the rotary shaft, the rotary sleeve can rotate around the rotary shaft and also can axially move up and down along the rotary shaft under the effect of the gravity, and a rotation limiting hole is formed in the rotary sleeve and is movably connected with the rotary block of the drawing pen assembly. The elliptic trammels have the advantage that the elliptic trammels are smart in design and are a practical tool for accurately drawing ellipses.

Description

technical field [0001] The invention belongs to the technical field of drawing instruments, and in particular relates to an ellipse gauge. Background technique [0002] In the current teaching work, the ellipse is mostly hand-painted by the teacher. As a schematic diagram, it cannot accurately reflect the nature of the ellipse, which makes students not intuitive enough to understand the nature of the ellipse. For this reason, the definition method of drawing an ellipse appeared, such as figure 1 As shown, this drawing method is based on the definition of an ellipse, that is, an ellipse refers to the trajectory of a point whose sum of distances to two fixed points on a plane is a constant value. Therefore, when using this drawing method to draw an ellipse, it is first necessary to fix two focal points f 1 , f 2 , then, use a rope to determine the fixed length, and finally, use a brush along both ends to fix at the focal point f 1 , f 2 Draw the outline of an ellipse with ...

AI Technical Summary

Problems solved by technology

[0002] In the current teaching work, the ellipse is mostly hand-painted by the teacher. As a schematic diagram, it cannot accurately reflect the nature of the ellipse, so that students' understanding of the nature of the ellipse is not intuitive enough.

For this reason, the definition method of drawing an ellipse appeared, such as figure 1 As shown, this drawing method is based on the definition of an ellipse, that is, an ellipse refers to the trajectory of a point whose sum of distances to two fixed points on a plane is a constant value. Therefore, when using this drawing method to draw an ellipse, it is first necessary to fix two focal points f 1 , f 2 , then, use a rope to determine the fixed length, and finally, use a brush along both ends to fix at the focal point f 1 , f 2 Draw the outline of an ellipse with a rope that is kept tight all the time. The disadvantage of this drawing method is that it is not easy to operate when drawing, and it is difficult to accurately determine the length of the center, major axis and minor axis of the drawn ellipse.

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