| 摘要 |
FIELD: woodworking industry. SUBSTANCE: device for checking quality of wooden boards has clamp 1 which by means of screw grips 2 is fastened on board. Prism 9 by its sharp part is installed in center of middle layer of board along its plane and is pressed against it. Load 5 is located on lever 4 in first position nearest as to rod 6, and determined by means of indicator 8 is value of displacement of prism 9 at this location of weight. Then, weight 5 is moved along lever 4 to second position remotest from rod 6, and determined by means of indicator 8 is new value of displacement of prism 9. Difference between reading of indicator 8 at two different positions of weight 5 on lever 4 denotes the value of displacement of prism 9 penetrating into middle layer of board. This indication is used to determine tensile strength of board. EFFECT: high efficiency. 1 cl, 2 dwg |
