Title:
CAPACITY TYPE ELECTROSTATIC SERVO ACCELERATION SENSOR
Document Type and Number:
Japanese Patent JP3216455
Kind Code:
B2
Abstract:
PURPOSE: To provide a capacity type electrostatic servo acceleration sensor that unnecessitates a highly accurate oscillator and can detect acceleration with high sensitivity and reduce an error.
CONSTITUTION: A PAM circuit 7 is adopted to perform a pulse amplitude modulation proportional to an acceleration G, and the product of the open gain and voltage feedback rate of an operational amplifier A3 constituting a comparator 5 is sufficiently made larger than one. The measurement mode period and dynamic balance mode period are repeated alternately. In the measurement mode period, a switch &phiv 9 is turned on, a switch &phiv 10 is turned off, a movable electrode 11 is not restricted by servo, a switch &phiv 11 is turned off, a switch &phiv 8 is turned on, and a detection voltage Vsc corresponding to the acceleration G is subject to sample-holding. In the dynamic balance mode period, a switch &phiv 9 is turned off, a switch &phiv 10 is turned on, a switch &phiv 11 is turned on while the electrode 11 is restricted by servo based on the detection voltage Vsc obtained by sample holding, and the electrode 11 is shortcircuited to circuit ground potential.
Inventors:
Tomio Shibano
Application Number:
JP32086094A
Publication Date:
October 09, 2001
Filing Date:
December 22, 1994
Export Citation:
Assignee:
MURATA MANUFACTURING CO.,LTD.
International Classes:
G01P15/125; G01P15/13; G01R27/26; (IPC1-7): G01P15/13
Domestic Patent References:
| JP6281669A | ||||
| JP5340958A | ||||
| JP5340960A | ||||
| JP3501887A |
Other References:
Ｈ．Ｌｅｕｔｈｏｌｄ ｅｔ ａｌ．，”Ａｎ ＡＳＩＣ ｆｏｒ Ｈｉｇｈ−ｒｅｓｏｌｕｔｉｏｎ Ｃａｐａｃｉｔｉｖｅ Ｍｉｃｒｏａｃｃｅｌｅｒｏｍｅｔｅｒｓ”，Ｓｅｎｓｏｒｓ ａｎｄ Ａｃｔｕａｔｏｒｓ，Ｎｅｔｈｅｒｌａｎｄｓ，１９９０，Ｖｏｌ．２１，Ｎｏ．１／３，ｐ．２７８−２８１
Ｍａｒｋ Ｖａｎ Ｐａｅｍｅｌ，”Ｉｎｔｅｒｆａｃｅ Ｃｉｒｃｕｉｔ ｆｏｒ Ｃａｐａｃｉｔｉｖｅ Ａｃｃｅｌｅｒｏｍｅｔｅｒ”，Ｓｅｎｓｏｒｓ ａｎｄ Ａｃｔｕａｔｏｒｓ，Ｎｅｔｈｅｒｌａｎｄｓ，１９８９，Ｖｏｌ．１７，Ｎｏ．３／４，ｐ．６２９−６３７
Ｍａｒｋ Ｖａｎ Ｐａｅｍｅｌ，”Ｉｎｔｅｒｆａｃｅ Ｃｉｒｃｕｉｔ ｆｏｒ Ｃａｐａｃｉｔｉｖｅ Ａｃｃｅｌｅｒｏｍｅｔｅｒ”，Ｓｅｎｓｏｒｓ ａｎｄ Ａｃｔｕａｔｏｒｓ，Ｎｅｔｈｅｒｌａｎｄｓ，１９８９，Ｖｏｌ．１７，Ｎｏ．３／４，ｐ．６２９−６３７
Attorney, Agent or Firm:
Shinshiro Arichika
Previous Patent: Corona discharge type air cleaning devices
Next Patent: FUEL INJECTION CONTROL DEVICE
Next Patent: FUEL INJECTION CONTROL DEVICE