| 摘要 |
<p>A dispensing device is described in the form of a pump (10) for dispensing fluids in spray form. The device has a first piston (11) sliding in a first cylinder (15) and a second piston (12) of smaller cross-sectional area sliding in a second cylinder (16), the cylinders being in fluid communication. An inlet (31, 47) to the cylinders is provided and fluid is dispensed through an outlet (24, 25) extending through the first piston and to an outlet nozzle. A valve (28) normally closes the outlet. Springs (22, 29, 45) are provided urging the components of the device into their rest position. A metering chamber of fixed volume is formed by the second piston and cylinder, the second piston moving between limit positions defined by an abutment at the upper end of cylinder (16) and a discontinuity in the wall of the cylinder.</p> |
