To provide a pump device performing estimated terminal pressure constant control without causing insufficient water supply or insufficient water supply pressure.
This pump device includes: a pump 310; a pressure detection means 323 detecting discharge pressure; an electric motor 210 driving the pump; an estimated terminal pressure constant control calculation section 15 calculating and determining the relationship of the discharge pressure corresponding to the discharge flow rate of the pump 310 for substantially constantly regulating terminal pressure, between the minimum rotational speed Nb of the pump corresponding to the minimum required flow rate and the maximum rotational speed Nmax of the pump 310 corresponding to the maximum required flow rate; and a rotational speed control means 13 controlling the rotational speed of the electric motor 210 so that the discharge pressure to be detected is set to the discharge pressure according to the relationship determined by the calculation in response to the actual required flow rate. The estimated terminal pressure constant control calculation section 15 calculates and determines the relationship between the required flow rate and the discharge pressure with respect to the estimated maximum suction water level of the pump 310.
MAKINO TSUTOMU
MIKI RYOTA
KAWAGUCHI HITOSHI
| JPH0439689B2 | 1992-06-30 | |||
| JPS57113992A | 1982-07-15 | |||
| JPS6157193U | 1986-04-17 | |||
| JP2002005033A | 2002-01-09 |
Kiyoshi Miyakawa
Shigeo Shibata
Toshiyuki Kanai
Yuko Yoshimura
Haruhiko Kato
Kayoko Miyoko