| 摘要 |
<p>The square or rectangular frame (1) has two opposite sides (17,19) each with at least two inward pointing claw detents (2,3,4). Between them are provided rigid locating surfaces (7,8). On the other sides (18,20) are provided side limits (5,6). Plug-in units (11) are provided with tapered latches (13,14) which engage with the claw detents and sprung lugs (15) which latch against the locating surfaces.</p> |
