Azbil Corporation

Raita Mori

Shun Onuma

Takashi Watanabe

Motonori Futamura

Takayoshi Kawazu

Yasuhide Yoshikawa

Keisuke Obara

Satoshi Kamiya

Mitsuhiko Nagata

Mayuka Sakai

To calculate a probability of an optical sensor's irregular discharge, a light detection system includes an optical sensor, an application voltage generating circuit that applies a drive pulse voltage to the optical sensor, a discharge determining portion that detects the optical sensor's discharge, a discharge probability calculating portion that calculates a discharge probability in a first state in which light from an additional light source having a known light quantity is incident on the optical sensor or the additional light source is turned off, and in a second state in which the additional light source's turning-on/turning-off state is different from the first state and the drive pulse voltage's pulse width is the same as the first state, a sensitivity parameter storing portion that stores the optical sensor's sensitivity parameters, and another discharge probability calculating portion that calculates a discharge probability of the optical sensor's irregular discharge.

Light detection system and discharge probability calculating method

Vacuum gauge

To provide a pressure sensor housing that is less likely to cause temperature distribution inside a pressure sensor when the pressure sensor is disposed inside a heater block, a pressure sensor housing includes a hollow cylindrical member extending along a predetermined axis core. A pressure sensor element that detects the pressure of a fluid is accommodated inside the cylindrical member. The entire circumference of a side surface thereof is surrounded by an air layer in the first posture in which an axis core of a space is aligned with the predetermined axis core with the hollow member disposed in the space. The side surface is in contact with a wall surface defining the space at a plurality of points at the same time in a second posture, which is at least one of postures in which the predetermined axis core is eccentric with the axis core of the space.

Pressure sensor housing and pressure sensor being disposed inside a heater block

A flame detection system includes: an optical sensor that detects light generated from a light source; an applied voltage generating circuit that periodically applies a drive pulse voltage to the optical sensor, discharge determining portion that detects a discharge from the optical sensor, a discharge probability calculating portion that calculates a discharge probability based on a number of times of application of the drive pulse voltage and a number of times of discharge detected in the a first state in which the optical sensor is shielded from light and a second state in which the optical sensor can receive light, a sensitivity parameter storing portion storing known sensitivity parameters of the optical sensor; and a received light quantity calculating portion that calculates the received light quantity by the optical sensor in the second state based on the sensitivity parameters and the discharge probabilities calculated in the first and second states.

Flame detection system and received light quantity measuring method

To calculate a probability of an optical sensor's irregular discharge, a light detection system includes an optical sensor, an application voltage generating circuit that applies a drive pulse voltage to the optical sensor, a discharge determining portion that detects the optical sensor's discharge, a discharge probability calculating portion that calculates a discharge probability for each of first and second states in which the optical sensor is shielded from light and the drive pulse voltage's width in the second state is different from the first state, a sensitivity parameter storing portion storing the drive pulse voltage's reference pulse width as the optical sensor's sensitivity parameter, and another discharge probability calculating portion that calculates an irregular discharge's probability that occurs without depending on the optical sensor's received light quantity, based on the sensitivity parameter, and the discharge probabilities calculated and the drive pulse voltage's widths in the first and second states.

Light detection system, discharge probability calculating method, and received light quantity measuring method

To calculate received light quantity even when part of noise component's discharge probability is unknown, a light detection system includes a discharge probability calculating portion that calculates discharge probabilities for a first state in which a source's light with known light quantity impinges on an optical sensor, a second state in which the source's turning-on/turning-off state is the same as the first state with a drive pulse width applied to the optical sensor different from the first state, a third state in which the source's turning-on/turning-off state is different from the first and second states with the same pulse width as the first state, and a fourth state in which the source's turning-on/turning-off state is the same as the third state with the same pulse width as the second state, another discharge probability calculating portion that calculates regular and irregular discharges' probabilities, and a received light quantity calculating portion.

For calculating an optical sensor's regular-discharge probability, a light detection system includes the optical sensor, an application voltage generating circuit for applying a drive pulse voltage to the optical sensor, a discharge determining portion for detecting the optical sensor's discharge, a first discharge probability calculating portion, a sensitivity parameter storing portion for storing the optical sensor's sensitivity parameters, and a second discharge probability calculating portion for calculating a discharge probability of the optical sensor's regular discharge. The first discharge probability calculating portion calculates a discharge probability in: a first state in which light from an additional light source having a known light quantity is incident on the optical sensor or the additional light source is turned off; and a second state in which the additional light source's turning-on/turning-off status is different from the first state, with the drive pulse voltage's pulse width being the same as the first state.

A flame detection system includes: an optical sensor that detects light emitted from a light source; an applied voltage generating circuit that applies a drive pulse voltage to the optical sensor; a discharge determining portion that detects a discharge from the optical sensor; a discharge probability calculating portion calculates discharge probabilities in a first state and a second state in which the optical sensor is shielded from light and a pulse width of the drive pulse voltage is different; a storing portion storing a reference pulse width as a sensitivity parameter; and a discharge probability calculating portion that calculates a discharge probability of an irregular discharge occurring without depending on the received light quantity by the optical sensor based on the sensitivity parameter, the discharge probabilities calculated in the first and second states and the pulse widths of the drive pulse voltage in the first and second states.

Flame detection system, discharge probability calculating method, and received light quantity measuring method

A current discharge probability of a flame sensor is calculated based on the number of drive pulses applied to the flame sensor and the number of discharges determined to have occurred in the flame sensor after receiving the drive pulses. Degradation indices (degradation progress and remaining lifetime) indicating the current degradation state of the flame sensor are calculated based on the calculated current discharge probability of the flame sensor.

Flame detecting system

A sensitivity parameter storing portion stores, as known sensitivity parameters owned by a flame sensor, reference received light quantity, reference pulse width, probability of regular discharge, and probabilities of non-regular discharge in advance. The discharge probability is calculated based on the number of drive pulses applied to the flame sensor and the number of discharges determined to have occurred in the flame sensor having received the drive pulses. The calculated discharge probability and the known sensitivity parameters are used to calculate the received light quantity per unit time received by the flame sensor.

A sensitivity parameter storing portion stores, as known sensitivity parameters owned by a flame sensor, a reference received light quantity, a reference pulse width, a probability of regular discharge, and probabilities of non-regular discharge in advance. The discharge probability is calculated based on a number drive pulses applied to the flame sensor and a number of discharges determined to have occurred in the flame sensor having received the drive pulses. The calculated discharge probability and the known sensitivity parameters are used to calculate a received light quantity per unit time received by the flame sensor. A pulse width correcting portion is provided to correct the pulse width of the drive pulses generated by an applied voltage generating circuit so that the discharge probability equals a target discharge probability.

A flame detecting system includes a flame sensor to detect light and a calculating device, in which the calculating device includes an applied voltage generating portion configured to generate a pulse to drive the flame sensor, a voltage detecting portion configured to measure an electric signal flowing in the flame sensor, a storing portion configured to store sensitivity parameters of the flame sensor in advance, and a central processing unit configured to obtain a quantity of received light of flame using parameters of a known quantity of received light, a pulse width, and a discharge probability of the sensitivity parameters, and a discharge probability obtained from an actual pulse width and the measured number of discharge times, and in which a difference in sensitivity of individual flame sensors is corrected from sensitivity parameters related to a first flame sensor and sensitivity parameters related to a second flame sensor.

A flame detecting system capable of easily performing a deterioration diagnosis of a flame sensor without being provided with a shutter mechanism. The flame detecting system comprising a flame sensor to detect light, a calculating device, and a reference light source, in which the calculating device, by operations of a central processing unit CPU, is configured to execute a first mode at which the discharge probability in the flame sensor is measured when the reference light source is turned off and a second mode at which the discharge probability in the flame sensor is measured when the reference light source is turned on, and calculate a current discharge probability of the flame sensor from data obtained at the first mode and the second mode.

To easily obtain a quantity of received light with computation by only measuring pulses of an electric signal related to a flame sensor, a flame detecting system is disclosed comprising: a flame sensor to detect light and a calculating device, in which the calculating device includes an applied voltage generating portion configured to generate a pulse to drive the flame sensor, a voltage detecting portion configured to measure an electric signal flowing in the flame sensor, a storing portion configured to store sensitivity parameters of the flame sensor in advance, and a central processing unit configured to obtain a quantity of received light of a flame using parameters of a known quantity of received light, a pulse width, and a discharge probability of the sensitivity parameters, and a discharge probability obtained from an actual pulse width and the measured number of discharge times.

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Tokyo, Japan

Raita Mori