| 摘要 |
<p>998,131. Latch fastenings. A. M. AUBOIN, and R. F. V, GIRARD. Jan. 3, 1962 [Jan. 4, 1961], No. 264/62. Heading E2A. A latch fastening means comprises a male part 1 and a female part 2 each adapted to be carried by a respective one of two members to be fastened together, the male part having a convex surface 4 and the female part including a plate 5, a lever 7 pivoted to the plate and a rocking lever 9 pivoted only to the pivotable lever and having a concave surface 12 complementary in shape to the convex surface of the male part and being adapted under the loading of spring means to engage the convex surface of the male part to fasten the two parts together, the arrangement being such that the two parts cannot separate as regards normal movement of the two parts relative to each other until the rocking lever is moved by displacement of the lever pivoted to the plate. The male part is of substantially channel shape in cross-section and has a substantially plane outside surface 3 in addition to the convex outside surface 4. The lever 7 is pivoted to one side of the plate 5 and the pivot 10 for the rocking lever passes through a slot 11 in the plate 5. The concave surface 12 of the rocking lever is one surface of a flange. The plate 5 has a flange provided with a plane surface 6 which is adapted to engage the plane surface 3 of the keeper. The lever 7 is biased by a spring 14 so that the pivot 10 normally tends to engage the end of the slot 11 nearest the surface 6; the rocking lever is biased by a spring 15 to the position shown in Fig. 1. In use, as the parts 1 and 2 move together, the convex surface of the part 7 engages the left hand edge of the flange of the rocking lever and pivots both the rocking lever and the lever 7 anti-clockwise until a position is reached in which the rocking lever can swing clockwise under the influence of its spring 15; the surfaces 4 and 12 then engage each other since the lever 7 swings clockwise under the influence of its spring 14. During the movement of the parts 1 and 12 together, the surfaces 3 and 6 slide on each other. Any separating movement of the parts 1 and 2 causes the surfaces 4 and 12 to grip more tightly. To release the part 1 from the part 2, the lever 7 is rotated anticlockwise which lowers the rocking member out of engagement with the surface 12. In a modification, instead of two springs being used, a single spring connected between the rocking lever and the plate 5 is provided; in a further modification the spring instead of being connected between the rocking lever and the plate is connected to a cam on the pivot 10 which carries the rocking lever. A stop can be provided on the lever 7 to limit movement of the cam.</p> |
