Sensing instrument
First Claim
1. A sensing instrument which uses a sensing sensor including a piezoelectric resonator changing in natural frequency by the adsorption of a sample and which senses the adsorption of the sample based on the change in the natural frequency of the piezoelectric resonator, the instrument comprising:
- an oscillator circuit oscillating the piezoelectric resonator;
a measuring unit measuring a signal regarding a frequency of an oscillation output of the oscillator circuit;
a level detecting circuit detecting a signal level of the oscillation output of the oscillator circuit;
a level determinator determining that the signal level is normal when the signal level detected by the level detecting circuit is equal to or higher than a threshold value, and determining that the signal level is abnormal when the signal level is lower than the threshold value; and
a notifier notifying that the signal level is abnormal when the signal level is determined as abnormal by the level determinator.
1 Assignment
0 Petitions
Accused Products
Abstract
In a sensing instrument using a quartz sensor on whose front surface an adsorption layer for adsorbing a substance to be sensed is formed and which changes in natural frequency by the adsorption of the substance to be sensed, the present invention has an object to quickly detect a trouble of the quartz sensor to prevent an operator from recognizing an incorrect measurement result.
In the present invention, a level detecting circuit detecting a signal level of an oscillation output of an oscillator circuit is provided, and after the time for stabilization passes after the power-on time, a computer takes a level detection value therein to compare the signal level and a threshold value. Then, when the signal level is lower than the threshold value, the signal level is determined as abnormal and, for example, the abnormality notification is displayed on a display unit, whereby an operator is notified of the occurrence of the abnormality.
-
Citations
3 Claims
-
1. A sensing instrument which uses a sensing sensor including a piezoelectric resonator changing in natural frequency by the adsorption of a sample and which senses the adsorption of the sample based on the change in the natural frequency of the piezoelectric resonator, the instrument comprising:
-
an oscillator circuit oscillating the piezoelectric resonator; a measuring unit measuring a signal regarding a frequency of an oscillation output of the oscillator circuit; a level detecting circuit detecting a signal level of the oscillation output of the oscillator circuit; a level determinator determining that the signal level is normal when the signal level detected by the level detecting circuit is equal to or higher than a threshold value, and determining that the signal level is abnormal when the signal level is lower than the threshold value; and a notifier notifying that the signal level is abnormal when the signal level is determined as abnormal by the level determinator. - View Dependent Claims (2, 3)
-
Specification