Title:
PUMP DEVICE
Document Type and Number:
Japanese Patent JP2010242511
Kind Code:
A
Abstract:
To provide a general purpose pump device simply preventing an extreme drop of pumpage to the occurrence of cavitation.
If characteristics of motor rotation speed Nm and pump operation current value Im which are peculiar for occurrence of cavitation are detected at a point of time T5, and rise of pressure P in a pressure tank during increase of motor rotation speed Nm or drop of pressure P in the pressure tank during decrease of motor rotation speed Nm is not confirmed (a point of time T5'), it is determined that cavitation surely occurs and motor rotation speed is changed to inhibit occurrence of cavitation.
Inventors:
FUJITA KATSUTOSHI
KOBAYASHI TAKAHIRO
HONDA TOMOTAKA
KOBAYASHI TAKAHIRO
HONDA TOMOTAKA
Application Number:
JP2009089107A
Publication Date:
October 28, 2010
Filing Date:
April 01, 2009
Export Citation:
Assignee:
HITACHI APPLIANCES INC
International Classes:
F04D15/00
Domestic Patent References:
| JP2008101556A | 2008-05-01 | |||
| JP2008101556A | 2008-05-01 |
Attorney, Agent or Firm:
Isono Dozo
Etsuo Tada
Etsuo Tada