| 摘要 |
To clean the upper rim of a lavatory bowl from inside, the lavatory bowl is filled with water up to the upper rim with the addition of a cleaning agent, while sealing the discharge orifice by means of a water-filled air balloon, after which the air cushion resulting in the bowl rim is removed by a vent pipe, so that the cleaning agent can act. An air cushion does not result if the bowl rim is provided with a vent hole during manufacture.
|
