JPS5958317A - Flow rate measuring device - Google Patents

Abstract

PURPOSE:To accurately measure a flow rate by storing the ratio of error of a flow rate detector at the time of stopping of a booster pump and measuring the flow rate by finding the deflection between the error signal and detect signal of an erroneous amount outputting section at the time of operation of the booster pump. CONSTITUTION:To the titled device having plural flowmeters which measure the discharging flow rates of booster pumps with their flow rate measurement detectors, a booster pump controlling means 12-n which controls the operation and stoppage of a booster pump 10-n and outputs a signal A when the pump 10-n is stopped is installed. Moreover, a delaying means 13-n which receives the stop signal A of the controlling means 12-n and outputs a read signal C after a time, during which the amount of an electric current for discharging is regarded as zero, has passed is installed to the device. Then they are constituted in such a way that a detect signal from a flow rate detector 11-n is stored at the time of receiving the read signal C and an error signal E which is equal to the erroneous amount of the detect signal D is outputted from an outputting section 14-n and, at the same time, a flow rate signal F is outputted from a subtracting section 15-n by finding the deflection between the detect signal D and error signal E.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a flow rate measuring device that measures the flow rate sent by a plurality of pumps.

[Technical background of the invention and its problems]

FIG. 1 is a block diagram of a flow rate measuring device that measures the flow rate sent by a plurality of boost pumps.

The number of booster pumps 1-1 to 1-n of this flow rate measurement device is automatically controlled according to changes in flow rate, and the continuous pressure pumps 1-1 to 1-n are automatically controlled in order to average the continuous operation time. pump control section 2-1~2
The operation and stop are repeated at a predetermined period according to the operation and stop signal of -n. Each of the flow rate detectors 3-1 to 3-1 provided for each booster pump 1-1 to l''n in operation is
The flow rate is detected by J-n.

By the way, the characteristics of each of the 11ttM detectors 3-n to 3-n change over time during detection, and further change depending on the environmental conditions, such as temperature, at the location where the flow rate detectors 3-1 to 3-n are installed. This change in characteristics includes a zero point change where the detection signal B is sent even when the flow rate becomes zero, and
There are some changes. Among these, the zero point change is particularly important because the detection signal B includes a large error in the low flow rate region. Therefore, this zero point change is calibrated. Conventionally, this calibration is performed periodically by an operator. However, the frequency of calibration work is
~3-n are not fixed because the temperature etc. at which they are installed are different. Therefore, the actual calibration is done using the flow rate detector 3-1.
~． ? -N detection signal B is not keyed without causing a considerable error. Therefore, there is a possibility that accurate flow rate measurement may not be performed. Therefore, due to detection signal B, υ
A problem arises in that a large error occurs in the required initial value of the product of fluid consumption, control of m i'+4, efficiency @1 calculation, etc.

[Purpose of the invention]

The present invention-1 was developed in view of the above-mentioned circumstances, and an object of the present invention is to provide a flow rate measuring device that can accurately measure ff1t ff without being affected by zero point changes due to the passage of time, temperature, etc.

[Summary of the Invention] The present invention provides a flow rate measuring device in which a plurality of flow systems including a boost pump and a flow rate detector are overlapped, wherein the boost pump is sequentially operated and stopped by a boost pump control means, and the boost pump is stopped. In some cases, the error output means is operated after a time period during which the flow rate is deemed to be zero by the delay means, and the error output means stores the rate of change of the zero point occurring in the flow rate detector, and the pressure is increased. During operation of the pump, the error generated in the detection signal 46 from the flow rate detector is determined based on the rate of change stored in the error output means, and the error signal and the detection signal are further output by the energy reduction means. This is a flow rate measurement device that attempts to achieve the above objective by obtaining the deviation from the flow rate.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. FIG. 2 shows a configuration diagram of a flow rate measuring device using a plurality of units of boost pumps and flow rate detectors. 10-1 to 1 in the figure
0-n is a boost pump that is operated by the motor IPL and sends fluid.

11-1 to 11-n are flow rate detectors that detect the flow rate of fluid. The signals detected by the flow rate detectors 1-1 to 11-n are the boost pump control units 12-1 to 12-nX.
The delay units 131 to 13n% error are measured as the original flow rate by the output units I4-1 to 14-n and the subtraction units 15-1 to 15-n. First, each boost pump J? Control is performed to average the operation of the pumps 10-1 to 10-n, and each boost pump fxO-z~1
The stop signal B in the stop state at 0-n is transmitted to the delay unit 13-z.
~1.9- This is what is sent to n. Delay section 13-1 to 1
．． 9-n is Ascended IEI Nippon l0-1~l O-n
The reading signal C is sent to the error output units 14-1 to 14-n after a time has elapsed during which the flow rate is considered to be zero due to the stoppage of the flow rate. The error output parts Z4-Z to l4-n output the read signal C from the delay parts 73-7 to J3-n.
Flow rate detectors 11-1 to 11 when the boost pumps 10-1 to 10-n are stopped and the flow rate is considered to be zero.
The flow rate detector 11- depends on the magnitude of the detection signal from -n.
1 to 11-n (the ratio of the constant flow value to the detected output of the flow rate O is memorized, and the boost pumps 10-1 to 1
It outputs an error signal E corresponding to the error of the detection signal, which is determined by the ratio of the error stored during the 0-n operation.

Reduced n part 15-1 to 15 n IJ,, 3f fHil
r4 output eW 1 The deviation between the detection signal from l-1-11-n and the error signal E from the error output parts 14-1 to 14-n is calculated and the flow rate is outputted. be.

Next, the operation of this device t will be explained. For convenience of explanation, one flow h1-measuring system 10-1 to 15-1 will be described next. The number of Jjl, 1 pumps 10-1 in operation is controlled according to the flow rate by the continuous rotation to stop signal A of the jasper pump control unit 12-1, and the pumps are controlled and operated so that the operations are averaged. As a result, υ fluid is sent, and its flow rate is detected by the flow rate detector 11-1. Therefore,
Boost pump 10-1 boosts pressure, 4? Assume that the pump is stopped in response to a stop signal from the operation/stop No. 43A from the pump control section 12-1. This prevents fluid from being delivered. At the same time, the boost pump control section 12-1 transmits the stop signal B to the delay section 13-1.
Send to No.

The delay section 7.9-1 sends an R-inclusion signal C for reading the detection signal to the error output section 14-1 after the time period during which the flow rate is considered to be zero due to the input of the stop signal B has elapsed. As a result, the error output unit 14-1 outputs a signal DK from the i-quantity detector IJ-1 when the flow rate is considered to be zero, and detects the difference in the display meter caused by the passage of detection time, temperature, etc. Outputs the amount of change from the zero point.

Next, the operation when the boost pump 11-1 is in operation will be explained. First, the boost pump 10-1 is put into an operating state by the operation signal of the operation/stop signal A from the boost pump f control section 12-1. At the same time, the boost pump control section 1
The stop signal B of 2-1η and the like and the read signal C from the delay section 13-1 are no longer output. As a result, the error output unit 14-1 stops reading the detection signal, and changes the amount of change when the boost pump 0-1 is stopped by the rate p.
(%).

When measuring #L amount by this, 3icit detector 1
The detection signal from No. 1 is first output to the error output section Z4-1.
, the error signal E corresponding to the error of only the stored ratio P
becomes. Then, the deconcentration section 15-1 includes a flow rate detector 11'
The deviation between the detection signal from n and the error signal E of only the ratio P from the error output unit 14-1 is determined, and a flow rate signal F excluding the error is output.

Again, the boost pump 10-1 is connected to the column, and the pressure pump control unit 12-
Operation of 1 - Stops by stop signal A.

Then, the stop signal B and the read signal C are outputted in the same manner as in the above-described operation. As a result, the error output section 14-1
stores the error rate P-7 that occurs in the flow rate detector 1 no 1 when the flow rate is considered to be zero.

The above-mentioned operation is controlled in the number of operating units according to the flow rate, and is repeated at predetermined intervals to measure the flow rate.

Therefore, when the boost pump 10-1 is stopped, the error percentage P generated in the flow rate detector 1 NO 1 is outputted by the error output section 14-1.
1, and when the boost pump 10-1 is operating, the flow rate is measured as the meteor signal F by determining the deviation between the error signal E of the error output section 14-1 and the detection signal F.
Even if the No. 1 detection signal contains a phase change at the zero point that occurs during flow rate detection and due to environmental changes such as temperature, the flow rate can be accurately measured without being affected by this.

In addition, each booster pump 1O-11d: The operation is controlled sequentially at a predetermined cycle, and when the operation is stopped, the flow rate detector l
Since the percentage of error P that occurs in l-1 is newly stored,
The flow rate can always be accurately measured in response to changes in the characteristics of the flow rate detector 11-1.

Note that the present invention is not limited to the above embodiment. For example, as shown in FIG.
An abnormality determining section 16-1 is provided on the output end side of the flow rate detector ll-1, and the operating state of the flow rate detector ll-1 can be determined. This abnormality determination section 16-1 sets an abnormal level value of the error signal E in advance, and determines that there is an abnormality in the flow rate detector 1 NO 1 when the error signal E exceeds the abnormal level value. be.

Thereby, in addition to accurate flow rate measurement according to the above embodiment, it is possible to determine abnormality in the operation of the flow rate detector 11-1.

〔Effect of the invention〕

Is this invention a booster? The error rate that occurs in the flow rate detector when the pump is stopped is memorized, and the error signal obtained by the error rate is reduced from the detection signal when the boost pump is running to obtain a flow rate signal, which is used to measure the flow rate. It is possible to provide a flow rate measuring device that can accurately measure the flow rate without being affected by zero point changes due to the passage of time in detection, temperature, and the like.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional flow rate measuring device, FIG. 2 is a block diagram of a flow rate measuring device according to the present invention, and FIG. 3 is a block diagram of a modification of the present device. 10-n... Boost pump, 1NO-n... Flow rate detector, 12-n... Boost pump control section, 13-n... Delay section, 14-n... Error output section, 15-n... Subtraction section.

Claims (1)

[Claims] In a flow measuring device that includes a plurality of flow systems that measure the discharge flow rate of a boost pump with a flow rate detector, a boost pump that controls operation and stop of the boost pump and outputs a stop signal when the boost pump is stopped. control means;
A delay means that receives the stop signal of the external pressure pump control means outputs a read signal after a time period during which the discharge flow rate is considered to be zero, and stores the detection signal from the flow # detector in the read signal, and A flow rate measuring device characterized by IPj comprising: an output section that outputs a detection signal of the stored content; and a subtraction section that outputs a deviation between the detection signal of the flow rate detector and the output signal of the output section.