Pressure measuring apparatus
AssigneeSeiko Instruments Inc.
InventorTomoharu Tsuji
Life of this patent
Estimating the term…
Abstract
To provide a portable pressure measuring apparatus with a pressure sensor of highly accurate output and small electric power consumption. A pressure measuring apparatus of the invention is provided with an impedance bridge circuit (pressure sensor part) for measuring pressure; a drive unit (sensor driving part) for applying voltage to the above impedance bridge circuit; a measuring unit (voltmeter) for sampling and measuring the electric potential difference between the middle points in both arms of the above impedance bridge circuit at a fixed time interval; and a determining unit (control part) for determining whether the difference between the pressure this time and the previous pressure sampled and measured by the above measuring unit reaches a predetermined threshold or below.
Claims4
A pressure measuring apparatus comprising:
- an impedance bridge circuit for measuring pressure;
- a drive unit for applying voltage to the impedance bridge circuit;
- a measuring unit for sampling and measuring an electric potential difference between middle points in both arms of the impedance bridge circuit at a fixed time interval;
- and
- a determining unit for determining whether a difference between pressure this time and previous pressure sampled and measured by the measuring unit reaches a predetermined threshold or below.
A pressure measuring apparatus comprising:
- an impedance bridge circuit for measuring pressure;
- a drive unit for applying voltage in a pulse drive waveform to the impedance bridge circuit;
- and
- a measuring unit for sampling and measuring an electric potential difference between middle points in both arms of the impedance bridge circuit at a fixed time interval.
Dependencies are inferred from the claim text.