| 摘要 |
An acoustic cleaning apparatus comprises means for generating an acoustic signal at an operating frequency 13, the acoustic generator means 13 being coupled to a first end of a waveguide or resonator 12 having a length substantially equal to a quarter of the wavelength of the generated acoustic signal, the second end 17 of the waveguide 12 being open and adapted to radiate the acoustic signal towards the surface being cleaned. The waveguide 12 acts as a closed tube resonator which resonates at fundamental frequency and at odd multiples thereof. The waveguide 12 is preferably folded at one or more points along its length in order to reduce the overall size of the apparatus, this makes the apparatus suitable for carrying by a user. An acoustic generator is also disclosed. |
