| 摘要 |
A housing for a fire alarm transducer 10 comprises a base 11 and a removable head 12 rotatably mounted to the base 11. A locking projection 17 projects from the base and prevents the head from being rotated, so that the head is difficult to remove by hand. A tool 20 is provided for removing the head 12. The tool 20 comprises a cup-shaped body 21 and an elongate handle 22. The upper edge of the peripheral wall of the cup-shaped body 21 comprises castellations 23 defined by axially extending slots 24, spaced at intervals around the wall. The spacing of the slots 24 in the tool 20 corresponds with the spacing of fins 14 disposed around an annular opening 13 in the head 12 of the transducer 10. The head 12 can be removed by engaging the castellations 23 of the tool with the fins 14 around the opening 13 and then rotating the tool 20 in the counter-clockwise direction. The tool 20 depresses the locking projection 17, thereby allowing the head 12 to turn. The tool 20 supports the head 12 once it has been removed, so the head 12 can be lowered away from the ceiling. |
