| 摘要 |
The drawing compasses with easily adjustable head consists of the arm (A) and arm (B). The arm (A) has an element of friction (1) with three parallel planes of friction (2, 2') equipped with a medial crew hole with a viewport (4) which narrower than the diameter of the annular medial crew hole (3) and it is situated to the opposite side of the holder (5,6) closed to the pencil and needle, while the second arm (B) contains the element of friction (7) with two parallel planes of friction (8, 8') corresponding with the outer planes (2, 2') of friction related to the first element (1) of the first arm (A), while the parallel internal planes of friction (8, 8') are connected with the medial cylindrical element (9), an axle of which has a vertical position related to the plane of the internal planes of friction (8, 8') of the element of friction (7) closed to the second arm (B) is smaller than the distance of the outer planes of friction (2, 2') of the element of friction (1) related to the arm (A), which is able to be mounted and placed on the cylindrical element (9) of the second arm (B) with a capability of rotating through its crew medial hole (3) and the viewport (4).
|
