| 摘要 |
An electromagnetic pump for supplying liquid pressure pulses to oral hygiene devices imposing different loads thereon includes a plunger-core driven in one direction by an electromagnetic circuit supplied with constant frequency pulses at power line frequency, a spring providing a restoring force so that the plunger-core reciprocates. The plunger-core drives a pump for producing the liquid pressure pulses, advantageously by using one end of the plunger-core as the piston of a pump. The mechanical resonant frequency of the plunger-core and spring is higher than the applied pulse frequency, and predetermined to yield an approximately constant amplitude of reciprocation for different loads imposed on the pump. |
