06386229 is referenced by 12 patents and cites 3 patents.

The present invention aims to permit an easy and reliable predicting of abnormality of a solenoid valve before failure, by detecting operating times of the solenoid valve and discriminating, from the operating times, whether the changeover operation thereof is normal or abnormal. To achieve this, the position of a spool at an stroke end, is detected by position detecting means adhered to the solenoid valve; the movement starting time from the time point when the driving signal for the solenoid valve is turned on or turned off, to the time point when the valve member begins to move from the stroke end, and the movement completion time therefrom to the time point when the spool arrives at the stroke end are measured in a signal processing circuit

12,

from the detected position signal and the clock signal for measurement; whether the changeover operation of the valve member is normal or abnormal, is discriminated by comparing these operating times T

1

-T

4

with a plurality of standard values T

1

a

-T

4

a

and T

1

b

-T

4

b

previously inputted in the signal processing circuit

12;

and the display signal in response to the discrimination result is outputted.

Title
Method and device for managing operation of solenoid valve
Application Number
9/597410
Publication Number
6386229 (B1)
Application Date
June 19, 2000
Publication Date
May 14, 2002
Inventor
Makoto Ishikawa
Ibaraki
US
Nobuyuki Ishitsuka
Ibaraki
US
Fumio Morikawa
Ibaraki
US
Agent
Oblon Spivak McClelland Maier & Neustadt P C
US
Assignee
SMC Corporation
US
IPC
F16K 37/00
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