| 摘要 |
829,987. Suction cleaners. FISKER & NIELSEN A.S. July 11, 1958 [July 15, 1957], No. 22368/58. Class 8(1). The rate of air flow through a vacuum cleaner nozzle is varied in accordance with the degree to which the nozzle mouth is obturated by the surface being cleaned by running the motor 5, Fig. 1, at one or other of two speeds and effected by the arm 12a of a snap action switch 12 being actuated so as to connect a contact point 15 to contacts 13 or 14 for high and low speed running respectively by a feeler 24, Fig. 3, connected by a stud 22 to a flexible diaphragm 18 bounding a chamber 19 located in the pressure zone 9 of the cleaner and connected by ducts 21, 27 to the suction zone 3. A three-way cock 25 in the duct 21 has a bore 28 by which when the chamber 19 is cut off from zone 3 connects said chamber to the pressure zone 9 whereby the diaphragm 18 is rendered inoperative and the motor runs at one speed only. |
