| 摘要 |
<p>The catch is used for retaining a fire door, or the like, open and comprises a hollow cylindrical metal body containing a press-fit washer located at the midpoint of the body. The washer has a central bore in which one end of a coaxial rod-like core (2) is a press fit. The other end of the core is flush with the end of the body. A coil is wound in the annular space between core and body with its terminal wires passing through a hole in the washer. The catch is secured in position on a wall adjacent the door by a screw (6) which passes through a coaxial bore in the core. The screw head is countersunk in the end of the core, flush with the end of the body. A further cooperating metal washer is screwed to the door with a rubber ring between washer and door locking the screw against loosening.</p> |
