JPH10170322A - Display device for flowmeter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device for flowmeter which measures the pulse width of a pulse signal outputted to the outside without using any measuring instrument and, at the same time, does not require a fluid to be measured to be made to flow actually at the time of measurement. SOLUTION: A display device for flowmeter is constituted so that the device can output a pulse signal having a prescribed pulse width upon receiving a pulse width displaying mode command signal from an operating part 4 and, at the same time, can measure the pulse width and can display the pulse with on a displaying section 7. Therefore, no surplus measuring instrument is required, because a worker can adjust the pulse width of the pulse signal outputted to the outside by only selecting the pulse width displaying mode command signal from the operating part 4. In addition, such an advantage that the wasteful use of a liquid to be measured can be eliminated, and so on, is obtained, because it becomes unnecessary to make the liquid to actually flow through a flowmeter.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device of a flow meter provided with a pulse output circuit for outputting a pulse signal to the outside according to the flow rate of a liquid to be measured.

[0002]

2. Description of the Related Art Recently, the display devices of various flow meters have been digitized, and the display of the flow rate of a liquid to be measured has been digitized.
Accordingly, a pulse output circuit for outputting a pulse signal to the outside according to the flow rate of the liquid to be measured is provided, and the pulse signal output from the pulse output circuit is used for various digital processes. .

In this type of display device, a pulse signal output to the outside is configured to be output each time the flow rate of the liquid to be measured is measured by a predetermined amount. The pulse signal is adjusted in advance so as not to overlap with an adjacent pulse signal.

[0004]

When the pulse signal is used for various digital processing on the customer side, it is necessary to increase the pulse width of the pulse signal as required. At this time, the output terminal of the pulse output circuit is required. After connecting a measuring device such as an oscilloscope to the flowmeter, the measured liquid is actually flowed into the flow meter, and the pulse width is confirmed by the measuring device from the pulse output according to the flow rate, and this is set to a desired value. Has been adjusted. Therefore, not only is an expensive measuring device required, but also the liquid to be measured has to be actually flowed into the flow meter for pulse width measurement, which causes a disadvantage that the liquid to be measured is wasted.

SUMMARY OF THE INVENTION The object of the present invention is to eliminate the above-mentioned drawbacks, and to measure the pulse width of a pulse signal output to the outside without using a measuring device, and to measure the liquid to be measured at the time of the measurement. It is an object of the present invention to provide a display device of a flow meter which does not need to be flowed to a flow meter.

[0006]

An operation section for outputting various flow rate display mode command signals and pulse width display mode command signals, and a flow rate signal corresponding to the flow rate of the liquid to be measured in accordance with each flow rate display mode command signal. A control unit that measures and calculates a flow rate of a predetermined unit from this, a display unit that displays the calculated flow rate, and a display device of a flow meter including a pulse output circuit that outputs an output signal corresponding to the flow rate to the outside. When a pulse width display mode command signal is received from the operation unit, the flow rate display and the pulse output corresponding to the flow rate are stopped, the pulse output circuit is driven, and the pulse width of the pulse signal output from the pulse output circuit is measured. A control unit is provided for driving an internal timer and displaying the measured time on a display unit.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a display device of a flow meter for measuring a flow rate of a liquid to be measured, a counter unit 3 for integrating a flow rate pulse transmitted from a sensor unit 2 according to a flow rate of the liquid to be measured, and a mode command switch 4a. And an operation unit 4 having a step switch 4b and a reset switch 4c to output various command signals including a flow rate display mode command signal, and to display a flow rate corresponding to each flow rate display mode command signal and parameters necessary for various settings. Storage unit 5 for storing,
The control unit 6 reads the integrated value of the counter unit 3 at predetermined time intervals, performs necessary calculations according to each flow rate display mode command signal from the operation unit 4, and outputs the calculation result to a display unit 7 described later. A display section 7 for displaying flow rate information based on the flow rate display mode command signal from the section 4; and a pulse output circuit 8 for outputting a pulse signal having a predetermined pulse width to the outside each time a predetermined amount of liquid to be measured is measured. ing.

The mode command switch 4a normally outputs one of the display mode command signals, and when pressed, displays a flow rate mode such as an integrated flow rate, an instantaneous flow rate, a resettable integrated flow rate, a total cumulative flow rate, and a pulse width described later. The display mode is sequentially selected, and each mode command signal is output. When the mode command switch 4a is pressed together with the reset switch 4c, the setting mode is selected. In the setting mode, the parameters stored in advance can be changed. The step switch 4b is enabled only in the setting mode, increments the step number in accordance with the number of times of pressing, and returns to an initial value (0) when this value reaches a predetermined value. . Further, the reset switch 4c is configured to reset the resettable integrated flow value only when the resettable integrated flow rate is displayed.

The parameters stored in the storage unit 5 are as follows:
It consists of customer parameters, maintenance service parameters, and initial setting parameters. The customer parameter is an integration unit instruction value (integration unit: ml, l
Etc.), the total flow initial value, the reset flow total initial value, and the instantaneous flow unit instruction value (/ h,
/ Min etc.), an upper limit flow rate alarm value, a lower limit flow rate alarm value, and other indication values relating to the display of instantaneous flow rates, and other indication values required for liquid viscosity equalization flow rate display and need to be input on the customer side. I have. The maintenance service parameters include a segment check instruction value of the display unit 7, an input check instruction value, and other instruction values necessary for the maintenance service. Further, the initial setting parameters are a meter factor specific to the flow meter, which is input at a manufacturing stage of the display device 1, and the rotor 1 of the flow meter.
It is composed of parameters for various initial settings such as the number of pulses per rotation, parameters for ROM rewriting, and viscosity correction values of a plurality of liquids.

The pulse output circuit 8 includes a timer IC 8a
And a pulse output unit 8c for changing the timer time. When a pulse corresponding to the flow rate is input to the input terminal of the timer IC 8a, a pulse signal having a predetermined pulse width is output. . The adjuster 8
b changes the timer time by changing its value,
The pulse width of the pulse signal is changed by changing the timer time. Further, the pulse output section 8c is configured to output an open collector signal or a voltage contactless signal having the pulse width to the outside.

In any of the flow rate display modes, the control section 6 reads the count value of the counter section 3, calculates the flow rate of the liquid to be measured according to the flow rate display mode command signal, and displays this value on the display section. 7 is displayed. The control unit 6 is configured to output a one-shot pulse and drive the pulse output circuit 8 each time the measured liquid is measured by a predetermined amount, that is, each time the measurement value of the counter unit 3 reaches a predetermined value. ing. Further, when the pulse width display mode is selected by the mode command switch 4a, the controller 6 stops the display of the flow rate of the liquid to be measured and the pulse output according to the flow rate, and then, as shown in FIG. Timer IC for pulse output circuit with one-shot pulse
Output to 2) Initialize the measurement time of the internal timer. 3) The internal timer is driven after the rise of the pulse signal from the timer IC. 4) Wait for the fall of the pulse signal from the timer IC and stop the internal timer. 5) Read the measured time of the internal timer and display it on the display unit. 6) It is determined whether or not the mode is the pulse width display mode. When the mode is the pulse width display mode, the procedure returns to 1). 7) Return. It is configured so that

In the display device of the flow meter, in any of the flow display modes, necessary parameters are called from the storage unit 5 in response to the flow display mode command signal from the mode command switch 4a, and these parameters and the liquid to be measured are read. A predetermined flow rate is calculated from the integrated value of the counter unit 3 that integrates the number of flow rate pulses corresponding to the flow rate of the flow rate, and this is displayed on the display unit 7. When the pulse width measurement mode is selected by the display mode command switch 4a, a one-shot pulse is sent to the timer IC 8a of the pulse output circuit 8,
The measurement time of the internal timer is initialized. At the same time, the timer IC 8a operates to output a pulse signal having a pulse width corresponding to the value of the adjuster 8b to the pulse output unit 8c, and a desired pulse signal is output from the pulse output unit 8c to the outside.

At the same time as the pulse signal, an internal timer operates to measure the pulse width. When the pulse signal falls, the internal timer is stopped, the measured time of the timer is read, and this is displayed on the display unit 7. Therefore, the operator can know the pulse width of the pulse signal output to the outside from the display unit 7 by numerical values.

[0014]

As described above, according to the present invention, when a pulse width display mode command signal is received from the operation unit, a predetermined pulse signal is output to the outside, and the pulse width is measured and displayed on the display unit. The operator can adjust the pulse width of the pulse signal to be output to the outside simply by selecting the pulse width display mode from the operation unit, which eliminates the need for extra measuring equipment. Alternatively, there is an advantage that there is no need to actually flow the liquid to be measured into the flow meter when adjusting the pulse width, and there is no waste of the liquid to be measured.

[Brief description of the drawings]

FIG. 1 is a schematic view of a display device of a flow meter according to the present invention.

FIG. 2 is a flowchart illustrating an operation of a control unit according to the present invention in a pulse width display mode.

[Explanation of symbols]

 Reference Signs List 1 display device 2 sensor unit 3 counter unit 4 operation unit 4a mode command switch 4b step switch 4c reset switch 5 storage unit 6 control unit 7 display unit 8 pulse output circuit 8a timer IC 8b adjuster 8c pulse output unit

Claims (1)

[Claims] An operation section for outputting various flow rate display mode command signals and a pulse width display mode command signal, and a flow rate signal corresponding to a flow rate of a liquid to be measured is measured in accordance with each flow rate display mode command signal. A control unit for calculating a flow rate of a predetermined unit, a display unit for displaying the calculated flow rate, and a pulse meter output device for outputting an output signal corresponding to the flow rate to an external device. When the pulse width display mode command signal is received, the flow rate display and the pulse output corresponding to the flow rate are stopped, the pulse output circuit is driven, and the internal timer that measures the pulse width of the pulse signal output from the pulse output circuit is driven. And a control unit for displaying the measured time on a display unit.