Claims
- 1. A safety and fixing mechanism for a fixed shape and a movable shape, the movable shape being movable relative to the fixed shape along an axis, comprisinga ratchet mechanism having a support that is fastened to the fixed shape, a ratchet element that is movably guided by said support in a direction substantially perpendicular to the axis, said element having an end portion that protrudes from the fixed shape toward the movable shape, said end portion having a flat end surface parallel to the axis and an inclined end surface inclined to the axis, and a spring biasing said element relative to the fixed shape toward the movable shape; and a perforated strip fastened to the movable shape and having a plurality of spaced-apart holes lying in a row parallel to the axis, each hole being adapted to receive the end portion of the element, and wherein the ratchet mechanism allows movement of the movable shape relative to the fixed shape in one direction by displacement of the element from each hole against the bias of the spring by a force applied by an edge of each hole on the inclined end surface of the element and stops movement of the movable shape in the other direction by protrusion of the end portion into one of the holes under the biasing of the spring.
- 2. The safety and fixing mechanism according to claim 1, wherein the flat surface of the end of the element is oriented so that it contacts surfaces of the perforated strip between the holes alternatively with surfaces of the movable shape in sliding relation when the movable shape is moving in said one direction.
- 3. The safety and fixing mechanism according to claim 1, wherein the edge of each hole in the perforated strip that engages the inclined surface of the element is a flat edge.
- 4. The safety and fixing mechanism according to claim 3, wherein each hole in the perforated strip has a semi-circular edge opposite the flat edge.
Priority Claims (1)
Number |
Date |
Country |
Kind |
9700398 |
Feb 1997 |
ES |
|
Parent Case Info
This application is a continuation of PCT/ES98/00033 Feb. 17, 1998.
US Referenced Citations (7)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0245236 |
Aug 1979 |
ES |
Continuations (1)
|
Number |
Date |
Country |
Parent |
PCT/ES98/00033 |
Feb 1998 |
US |
Child |
09/178261 |
|
US |