| 摘要 |
<p>A vacuum cleaning head includes a pressure chamber (176) comprising a first chamber section (194) and a second chamber section (196) which is moveable relative to the first chamber section (194) in response to a pressure differential thereacross from a first position to a second position, and a control mechanism (214, 238) located within the pressure chamber (176). The control mechanism (214, 238) has a first state for inhibiting the movement of the second chamber section (196) in response to said pressure differential beyond a third position intermediate the first and second positions, and a second state for allowing the second chamber section (196) to move in response to said pressure differential to the second position. The control mechanism (214, 238) is arranged to change between the first and second states in response to a movement of the second chamber section (196) from the third position. This can allow the pressure chamber to toggle between different configurations through varying the pressure differential across the second chamber section, for example to raise or lower part of the cleaner head, or to selectively activate or deactivate an agitator.</p> |
