JPS62187221A - Flow rate pulse output system - Google Patents

Abstract

PURPOSE:To extract flow rate pulses with high resolution, to remove an error due to the reversing of a rotator, and to output accurate flow rate pulses by performing the addition, subtraction, and integration of output backward rotation pulses and forward rotation pulses which are outputted later. CONSTITUTION:Pluse generating circuit parts (U1-U2 and D1-D2) extract pulses which synchronize with the leading and trailing of A-phase pulses and have a pulse repetitive frequency twice as high as the A-phase pulses. Then, forward rotation pulses are outputted from a gate as flow rate pulses and when backward rotation pulses are outputted, the gate is closed to stop the output of the flow rate pulses, so as to remove an error. Namely, reverse current error removing circuits (FF circuits 12 and 15), etc., stop the output of the number of backward rotation pulses and the output of forward rotation pulses as many as the backward rotation pulses to eliminate repetitive metering due to the reflow of fluid which flows backward and measure only the actual flow rate, so the accurate flow rate is measured.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is based on pulses of two phases, A and B, which are different in phase from each other and are outputted from a flow rate measurement unit in accordance with the position of the rotor. The present invention relates to a '11 pulse output method for forming and outputting an H pulse.

[Prior Art] When transmitting a flow rate signal remotely in a flow meter such as a flow meter, a turbine meter, etc., it is possible to detect the rotational position of a rotor such as an oval gear or a turbine and transmit it as a flow rate pulse signal. This is commonly done. In this flow rate pulse, 1 pulse corresponds to a fixed amount of fluid. Therefore, the flow rate can be determined by receiving the Iiii, t pulse signal, counting the pulses, and integrating the counted values.

By the way, in recent years, due to the need for precise flow control, i
ll, it is required to accurately detect the amount with high resolution.

As a method of detecting the flow rate with high resolution, a method of extracting a large number of flow rate pulses for one revolution of one rotor can be considered. For example, a plurality of pairs of photoelectric sensors consisting of a light emitting element and a light receiving element are prepared, and these are arranged at equal intervals along the rotational surface of an encoder that rotates in synchronization with the rotor. There is a method to obtain the same number of flow pulses.

In addition, in this type of flowmeter, when the flow rate is constant, flow rate pulses are transmitted at regular intervals, but in the case of pulsating flow, there are many opportunities for the single rotor to rotate in the opposite direction. . In this case, if the flow rate pulses are counted as they are, the amount of fluid that has flowed back will be added, resulting in a large error.

Therefore, in order to accurately detect the flow rate, conventionally, for example,
Two sets of photoelectric sensors are arranged to extract two-phase pulses with different phases, and these two-phase pulses are used to distinguish between forward and reverse rotation. Each flow rate pulse is input to an addition/subtraction counter to allow the flow to flow back and forth. A method is adopted in which the flow rate is subtracted and the net positive rotation flow rate pulses are integrated.

[Problems to be solved by the invention] By the way, the conventional method of measuring flow rate with high resolution has
This requires the arrangement of a large number of photoelectric sensors, making the structure complex, and the pulse interval is adjusted by the arrangement interval of the photoelectric sensors, which has the disadvantage of requiring time and effort to manufacture. Also, each requires a circuit to process the signals from them.
The disadvantage is that the circuit configuration is also complicated. Moreover, this method is structurally difficult to apply to flowmeters that have already been manufactured, as it requires the installation of a new photoelectric sensor, etc., and has the drawback that it cannot be applied to improve conventional products. .

Further, in the conventional method described above, when the pulsation rate increases and the frequency of forward and reverse rotation increases, there is a problem that direction discrimination becomes impossible, making accurate measurement difficult. This appears especially in wJ''A when a large number of flow pulses are taken out per rotor rotation to increase the resolution.
Along with achieving high resolution, it is necessary to eliminate errors due to pulsation.

The present invention was made to solve such problems,
It is possible to extract high-resolution flow pulses with the in-cylinder configuration, and it can also be applied to already manufactured products, and it eliminates errors caused by reverse rotation of the rotor due to fluid pulsation. The purpose of this invention is to provide a flow rate pulse output method that can output accurate meteor pulses.

[F stage for solving the problem] The first and second inventions of the present application generate flow rate pulses based on two phase pulses, A and B, which have different phases from each other and are outputted from the flow rate measurement unit in accordance with the position of the rotor. It is applied to the flow rate pulse output method that forms and outputs.

The first invention of the present application solves the problem described in F, and as the L stage, the level of the B-phase pulse signal with respect to the rising edge of the A-phase pulse signal,
Depending on the combination determined by the level of the B-phase pulse signal with respect to the falling edge of the A-phase pulse signal, and the phase lead/lag of the A and B two-phase pulses during forward and reverse rotation of the rotor,
A forward rotation pulse or a reverse rotation pulse with twice the pulse repetition frequency is formed respectively, and if the formed pulse is a forward rotation pulse, the output gate is opened, and on the other hand, the formed pulse is a reverse rotation pulse. When this happens, close the output gate, and from now on,
The present invention is characterized in that the forward rotation pulse and the reverse rotation pulse are added and subtracted, and when the number of forward rotation pulses exceeds the number of reverse rotation pulses, the output gate is opened and the normal rotation pulse is outputted as 1+4 pulses.

In addition, the second invention of the present application, as a means for solving the above-mentioned problem, replaces the portions of the f-stage solution of the first invention, which each form a forward rotation pulse or a reverse rotation pulse with twice the pulse repetition frequency, with an A-phase pulse. The level of the B-phase pulse signal -J in response to the rising edge of the signal, the level of the A-phase pulse signal in response to the rising edge of the B-phase pulse signal, the level of the B-phase pulse signal in response to the falling edge of the A-phase pulse signal, and the level of the B-phase pulse signal in response to the falling edge of the A-phase pulse signal. The pulse repetition frequency is quadrupled according to the combination determined by the phase lead/lag of the A and B 2-phase pulses during forward and reverse rotation of the rotor with respect to the level of the A-phase pulse signal with respect to the falling edge of the pulse signal. This is characterized in that a forward rotation pulse or a reverse rotation pulse is formed respectively.

[Operation] The present invention combines the rise and fall of one of two phase pulses, A and B, which are different in phase from each other, and the high and low signal levels of the other signal, which are output from the flow rate measurement unit in accordance with the rotor position. In the first invention, a pulse with twice the pulse repetition frequency is extracted, and in the second invention, a pulse with four times the pulse repetition frequency is extracted.

That is, in the first invention, the pulse repetition frequency synchronized with the rise and fall of the A-phase pulse is determined by a logical combination of the rise and fall of the A-phase pulse and the high-low signal level of the B-phase pulse. A pulse twice as large as the A-phase pulse is extracted. In this case, if the high-level width and low-level width of the A-phase pulse are large, pulses output at equal intervals can be obtained.

For this purpose, for example, it is a prerequisite that the light reflecting portions and non-reflecting portions of the encoder are alternately arranged with the same angular width.

In addition, in the second invention, the A-phase and B-phase
Synchronized with the rise and rise of the phase pulse. A pulse whose pulse repetition frequency is four times that of the A-phase (B-phase) pulse is extracted. In this case, the high-level width and low-level width of the A-phase and B-phase pulses are equal, and the phase difference between them is π/
If it is 2, pulses output at equal intervals can be obtained. For this purpose, for example, the light reflecting parts and non-reflecting parts of the encoder are arranged alternately with the same angular width, and
It is assumed that the reflection points on the encoders of the two sets of photoelectric sensors that take out the A-phase pulse and the B-phase pulse are arranged at an interval of 174 wavelengths of the A-phase pulse and the B-phase pulse, respectively.

The first aspect of the present invention is that when taking out pulses as described above, the phases of the A and B two-phase pulses are, for example,
With the A phase as the reference, if the B phase is delayed, it is 1: rotation, and if the B phase is ahead, it is reverse rotation, then the rising and rising edges of one of the pulses of the A and B2 phases, and the signal of the other. +E rotation and reverse rotation are distinguished by utilizing the fact that the combination of level high and low is logically different between 1 [rotation and reverse rotation. Output each pulse.

Here, in the case of a normal rotation pulse, one pulse is normally output from the gate as it is as a 1i-presenting pulse. On the other hand, if a reverse pulse is output.

,! ′#Close the gate to remove the difference! i Stop outputting the presentation pulse.

In order to eliminate the error caused by this reversal, the first part of the present application.
The second invention adds and subtracts and integrates the output reverse rotation pulse and the forward rotation pulse output thereafter. That is, a reverse rotation pulse and a forward rotation pulse are added with different signs, and when the number of forward rotation pulses output later exceeds the number of reverse rotation pulses output until then after the gate is closed, the gate is opened. Thereafter, normal rotation pulses are output as flow rate pulses until reverse rotation pulses are output.

In this way, by stopping the output of the number of reverse rotation pulses and the output of the same number of forward rotation pulses, it is possible to eliminate duplicate metering due to the reflow of the fluid that has flown backwards.
Only the actual flow rate can be measured, allowing for accurate measurements.

[Example] Embodiments of the present invention will be described with reference to the drawings.

Configuration of First Embodiment> FIG. 1 shows the configuration of a circuit that forms flow rate pulses by applying a first embodiment of the tN,:IX pulse output system of the present invention.

As shown in the figure, the flow rate pulse output method of this embodiment is as follows:
A flow rate pulse is formed based on pulses of two phases, A and B, which are different in phase from each other and are output from the flow rate measurement part of the flow meter 2 installed in the wave path pipe l through which the non-measured fluid flows, corresponding to the position of the rotation f. . Its basic configuration includes a pulse forming circuit that discriminates between forward rotation and reverse rotation of the rotor from the A and B phase pulses, and forms a forward rotation pulse or a reverse rotation pulse with twice the pulse repetition frequency, respectively, and a rotation It has a backflow error elimination circuit section that eliminates a flow rate error caused by reverse rotation of the child.

As shown in FIG. 1, the pulse forming circuit section includes pulse forming sections Ul and U2 for taking out normal rotation pulses, pulse forming sections DI and D2 for taking out reverse rotation pulses, and an OR gate circuit 9 for calculating the logical sum of these pulses. .10.

In addition, as shown in the figure, the reverse flow error elimination circuit section up-counts the forward rotation pulse as a circuit for preventing the occurrence of an error when a reverse rotation pulse is output.
a recenterable up-down counter (hereinafter abbreviated as counter) 11 that counts down the reverse pulse;
A flip-flop circuit 12 that is set by the carry output of the counter 11 and reset by the pollo output.
, an AND gate circuit 13 whose gate opening/closing is controlled by the Q terminal output of the flip-flop circuit 12, and which outputs the normal rotation pulse outputted from the OR gate circuit 9 in L as an If m pulse from the output terminal 14; A flip-flop circuit 15 is set by a reversal pulse output from the OR gate circuit 1O and reset by a flow rate pulse output from the output terminal 14, and a flip-flop circuit 15 is triggered by the Q terminal output of the flip-flop circuit 15 and outputs a pulse to L. A one-shot multi-vibrator (hereinafter abbreviated as "one-shot multi") 18 is provided to send data to the clear terminal CLR of the counter 11.

The pulse forming units U1 and Dl have in common an inverter 5 that inverts the B-phase pulse from the flow rate measuring unit of the flow meter 2.

The pulse forming unit U1 is a one-shot multivibrator (
Hereinafter, it will be abbreviated as one-shot multi. ) 3, and an AND gate circuit 7 which performs the logical product of the pulse of the one-shot multi 3 and the phase-inverted B-phase pulse from the L inverter 5.

The pulse forming unit DI also includes an inverter 8 that inverts the phase of the A-phase pulse, and a one-shot multivibrator ( (hereinafter abbreviated as one-shot multi) 4, the pulse of the one-shot multi 4, and the B-phase pulse whose phase has been inverted to a high level by the inverter 5. are doing.

On the other hand, the pulse forming ID 2 includes a one-shot multi 3 that outputs a pulse using the rising edge of the A-phase pulse as a trigger, and an AND gate circuit 7 that takes an AND of the pulse of the one-shot multi 3 and the B-phase pulse. ing.

In addition, the pulse type I& section U2 includes an inverter 8 that inverts the phase of the A-phase pulse, and a one-shot multi-channel pulse generator that outputs a pulse triggered by the falling of the A-phase pulse inverted by the inverter 6. 4, and an AND gate circuit 8 which takes the AND of the pulse of the one-shot multi 4 and the B-phase pulse.

The flow rate measurement unit 1.4 has a function of detecting the rotational position of a rotor (not shown) and outputting pulses of two phases, A and B. This function is achieved by, for example, an encoder 17 as shown in FIG.
, a B-phase pulse photoelectric sensor 18, and amplifiers and waveform shaping circuits for each of the A and B phases (none of which are shown).

As shown in the figure, the encoder 17 has non-reflective portions 1.77 consisting of through holes and reflective portions 17R arranged alternately at equal intervals. When the lengths in the circumferential direction of both are made equal, the boundary parts 17U and 17D of both are arranged at equal intervals.

As shown in FIG. 6, the A-phase pulse photoelectric sensor 18 and the B-phase pulse photoelectric sensor 19 are such that when the encoder 17 rotates clockwise (this is referred to as forward rotation), the former is more sensitive than the latter. They are arranged so that the phase advances. In this case, the phase is set to advance within the range of 0 and 0≦π/2.

That is, as shown in FIG. 6, the A-phase pulse photoelectric sensor 1
The light emitting element T-18L and the light receiving element 180 constituting 8,
Further, the reflection points RA and RB of the light emitting element 19L and the light receiving element 190 constituting the B-phase pulse photoelectric sensor 19 in the reflection part 17R of the encoder 17 are located at the boundary part 17U.
and 170, and are arranged so that they do not overlap. Preferably, the distance between reflection points RA and RB is set to be 1/2 of the distance between boundary portions 17LI and 170. The example shown in FIG. 6 is set like this.

Therefore, the A-phase pulse and the B-phase pulse are in a state where the phase of the former is advanced by 1/4 wavelength from the latter during forward rotation.

Moreover, when reverse Ur1 is turned, this is reversed.

Functions of the First Embodiment> The functions of the first embodiment of the present invention will be described with reference to the drawings in L and FIGS. 4 and 5.

First, the A-phase pulse and the B-phase pulse used in this embodiment are used to control the rotation of a rotor rotating in the measurement section of the flowmeter 2 using an encoder 17 and two sets of photoelectric sensors as shown in FIG. It is detected by sensors 18 and 19, and is formed by shaping the waveform. The analog waveform and the pulse waveform after waveform shaping are shown in FIG. 4. In the case of this embodiment, since the encoder 17 shown in FIG. Reflection part 17R (
The number of outputs is equal to the number of non-reflective portions 17T).

The A-phase pulse and B-phase pulse output in this way are input to the pulse forming units Ul, 01.02, and U2.

In the pulse forming unit U1, a pulse is outputted by the one-shot multi 3 using the rising edge of the A-phase pulse as a trigger, and the AND gate circuit 7 calculates the logical product of this pulse and the B-phase pulse level inverted by the inverter 6. Find it at On the other hand, in the pulse forming section DI, the falling edge of the A-phase pulse whose rising edge is inverted by the inverter 6 is used as a trigger to output a pulse from the one-shot multi 4, and this pulse and the pulse which is inverted by the inverter 6 The AND gate circuit 8 calculates the AND with the B-phase pulse level.

Here, if the rotor rotates forward, the A-phase pulse and the B-phase pulse are π/2 larger than the latter, as shown in FIG.
The phase is advanced. Therefore, in the AND gate circuit 7, when a pulse is output from the one-shot multi 3 using the rise of the A-phase pulse (AU in FIG. 2) as a trigger, the B-phase pulse (BL in FIG. 2) at a low level is output to the inverter. 5
It is inverted to high level at , both inputs of the AND gate become high level at the same time, and the same pulse as the one-shot multi 3 pulse is output as a normal rotation pulse.

Thereafter, in the AND gate circuit 8, when a pulse is output from the one-shot multi 4 using the fall of the A-phase pulse (AD in FIG. 2) as a trigger, the B-phase pulse (OH in FIG. 2) is at a high level. ) is inverted to a low level by the inverter 5, and the input to the AND gate circuit 8 does not become /\I level at the same time, and no inversion pulse is output.

On the other hand, if the rotor rotates in the opposite direction, the A-phase pulse and the B-phase pulse are delayed in phase by π/2 from the latter, as shown in FIG. Therefore, in the AND gate circuit 8,
When a pulse is output from the one-shot multi 4, the low level B-phase pulse (BL in Figure 3) is output to the inverter.
It is inverted at 5 and becomes the /\I level, and the meat input of the AND gate becomes high level at the same time, and the same pulse as the one-shot multi 4's pa and rus is output as a reverse pulse.

After this, in the AND gate circuit 7, when a pulse is output from the one-shot multi 3, the B-phase pulse (OH in Fig. 3), which is at the noise level, is inverted by the inverter 5 and becomes a low level, and the AND gate The meat inputs of the circuit 7 do not become high level at the same time, and no forward rotation pulse is output.

According to the circuit thus far, the conventional flow pulse shown in FIG. 4 as the 1x output mode is obtained. Tree nuts M (In M,
In order to obtain twice the number of pulses, pulse forming sections D2 and U2 are used.

In the pulse forming units D2 and U2, the B-phase pulse is input to the AND gate circuits 7 and 8 as it is without being inverted. The pulse forming section D2 has the same circuit configuration as the L pulse forming section U1, and the pulse forming section U
2 has the same circuit configuration as the pulse forming section DI.

Therefore, the pulse forming units D2 and U2 output the high level of the B-phase pulse (OH in FIG. 3) and the rising level of the A-phase pulse (OH) of the A-phase pulse.
By the combination of 〇) in Figure 3 and the combination of the high level of the B-phase pulse (OH in Figure 2) and the falling of the A-phase pulse (AD in Figure 2), the former generates a reverse rotation pulse and the latter generates a forward rotation. Pulses are output in the same manner as in the pulse forming units Ul and DI described above. In other combinations, no pulses are output.

The forward rotation pulse and the reverse rotation pulse outputted from the pulse forming units Ul, DI, D2, and U2 are respectively outputted by the OR gate circuit 9 and the OR gate circuit 1, respectively.
0, each is logically added and output as a logical sum. Therefore, depending on whether a pulse is output from the OR gate circuit 9 or from the OR gate circuit 10, it is determined whether the rotation of the rotor is normal or reverse.

Since the rising and falling edges of the A-phase pulse appear at equal intervals, this logical sum has a waveform as shown in FIG. 4 for the double output mode. According to this, a flow rate pulse having twice the pulse repetition frequency as in the conventional single output mode can be obtained.

Next, the forward rotation pulse and reverse rotation pulse outputted in this manner are inputted to the counter 11 in correspondence with the up terminal UP and the down terminal ON. This counter 11 counts up the pulse when a forward pulse is input to the up terminal UP, and counts down the pulse when a reverse pulse is input to the down terminal ON.

Regarding the operation of this counter 11 and its peripheral circuits,
This will be explained with reference to the time chart shown in FIG. In each area from work to ■ in the same figure, work is forward rotation, ■ is reverse rotation,
(2) and (2) each indicate a forward rotation IE. In this embodiment, the counter 11 has an up terminal UP and a down terminal D.
Counting is performed based on the falling edge of the pulse input to N.

During forward rotation machining, as shown in FIG. 5(b), forward rotation pulses are manually input to the up terminal UP of the counter 11 and counted. Here, it is assumed that the count f〆1 becomes n as shown in FIG. 5(a). At this time, the flip-flop circuit 15 is reset by a normal rotation pulse from the output terminal 14, which will be described later. Further, the flip-flop circuit 12 is also set by the carry output of the counter 11, and its Q terminal is at a high level. Therefore, a normal rotation pulse appears at the output terminal 14 after passing through the AND gate circuit 13.

Here, if the rotor of the Ii quantity meter 2 is reversed due to pulsation in the flow path pipe 1, etc., a y-calm occurs in the form of reverse rotation (■) in FIG. At this time, from the AND gate circuit 10, as shown in FIG.
), a reversal pulse is output, and the flip-flop circuit 15 is set by the rise of this reversal pulse, and its Q terminal output becomes high level. This acts as a trigger, and a pulse is output from the one-shot multi 16, which is input to the clear terminal CLR of the northern counter.
The counted value is cleared.

After this, the count value of the L counter 11 becomes "-1" as shown in FIG. 5(a) due to the fall of the E reverse pulse inputted to the down terminal DH, and the count value becomes "-1" as shown in FIG. 5(e). As shown, while outputting the pollo signal from the pollo terminal BL,
From now on, when a reverse pulse is input, the flip-flop circuit 1 starts counting down by this pollo signal.
2 is reset, and its Q terminal output becomes low level. As a result, the AND gate circuit 13 closes its gate, as shown in FIG. 5(f).

Next, as shown in FIG. 5(a), after three reverse rotation pulses are output, a forward rotation pulse is output, and when the state of forward rotation ■ is reached, this forward rotation pulse is incremented by the counter 11. It is counted and added to the count value counted at the time of the L rotation. Then, when the count value becomes "0", that is, when the same number of forward rotation pulses as reverse rotation pulses are counted, the counter 1
1 outputs a carry signal from the carry terminal CY.

This carry signal causes the flip-flop circuit 12 to enter the fortune set state, and its Q terminal output becomes high level. As a result, AND gate circuit 13 is opened (fifth
(See figure (f)).

Thereafter, a state of forward rotation (2) similar to the case of forward rotation I with shoes on is entered, and the forward rotation pulse outputted from the OR gate circuit 9 is outputted to the output terminal 14 as a flow rate pulse.

Configuration of Second Embodiment> FIG. 7 shows the configuration of a circuit that forms a flow rate pulse by applying the second embodiment of the flow rate pulse output system of the present invention.

As shown in the figure, the flow rate pulse output method of this embodiment is as follows:
The pulse forming circuit section is constructed in substantially the same manner as in the first embodiment, except that the pulse forming circuit section is constructed to form checkered pulses or reverse pulses each having a pulse repetition frequency of 4 times. Therefore, the description of the same parts as in the first embodiment will not be repeated, and the explanation will focus on the differences.

As shown in FIG. 7, the pulse forming circuit section includes pulse forming sections U1 to U4 that form forward rotation pulses, pulse forming sections D1 to D4 that form reverse rotation pulses, and an OR gate that calculates the logical sum of these pulses. It is configured with circuits 17 and 18.

Pulse forming section U1. U2. DI and D2 are the first
It has exactly the same configuration as the circuit indicated by the same reference numeral in the embodiment,
Acts the same.

Pulse forming units U3 and D3 are one-shot multi-3
, 4, inverter 5, 8 and AND gate circuit 7,
8, and has the same configuration as the pulse forming units Ul and Dl. In addition, the pulse forming section U4 and nil±
, Wan N, a lithomal sheep 34, an inverter 6, and AND gate circuits 7, 8, and the pulse forming section U
2 and D2. These pulse forming units U3, D3. U4 and D4 form the normal rotation pulse or the reverse rotation pulse by a logical combination of the rising or falling edge of the B-phase pulse and the high/low level of the A-phase pulse.

U2. It has a different effect from DI and D2.

Operation of Second Embodiment> The operation of this embodiment configured as described above will be explained.

The measuring section of the flowmeter to which this embodiment is applied may have the same 4R configuration as that of the first embodiment, but in this embodiment, the rising and falling pulses of both the A and B phases are used to In order to form a rotation pulse or a reversal pulse, in order to make each pulse equally spaced, in addition to making sure that the intervals between the eh and ker of both the A and B phase pulses are equal, the A phase pulse and the B phase pulse must be Set the phase difference to be exactly π/2.0
In this example, these conditions are satisfied.

Pulse shape X&, part U1. U2. DI and D2 operate exactly the same as the circuits shown in the first embodiment. Further, the pulse forming unit U3. U4, D3 and D4 are
The only difference is the relationship between the A-phase pulse and the B-phase pulse, and the actions in each part are the same as those in the pulse forming parts Ul, U2 .
It is the same as the corresponding circuit form and form of D1 and D2.

Pulse formation i'il! If Ul to U4 are expressed using the symbols shown in Fig. 2, (AU*BL), (BU*AH
), (AD*BH), and (BD″*AL) are combined to output a normal rotation pulse. In this case, the pulses are output in the order of Ul, U4, U2, and U3.

Moreover, the pulse type J& portions D1 to D4 are the same (represented using the symbols shown in FIG. 2, (AD*BL)).

(BU*AL), (AU*BH) Oyobi (BI
)*AH) (7) Outputs a reverse pulse by combination. In this case, the pulses are Dl, D3 . D2 and D
They are output in the order of 4.

The pulses from the pulse forming units U1 to U4 are logically added as normal pulses by the OR gate circuit 17 and output as a logical sum. Further, the pulses from the pulse forming section DI-D4 are logically added together as reverse pulses by the OR gate circuit 1B, and output as a logical sum. Therefore, depending on whether a pulse is output from the OR gate circuit 17 or from the OR gate circuit 18, it is determined whether the rotation of the rotor is normal or reverse.

This logical sum indicates that, as shown in FIG. 4, the rising and falling edges of the A-phase and B-phase pulses appear at equal intervals;
And, for the A-phase pulse and the B-phase pulse, the phase is π
/2 Since the settings are different, 4 is shown in Figure 4.
The waveform will be as shown in double output mode. According to this, a flow rate pulse with a pulse repetition frequency four times that of the conventional single output mode can be obtained.

Among the pulses formed in this way, the forward rotation pulse is
As long as the reverse pulse is not output, the flow rate pulse is directly output from the output terminal 14 via the AND gate circuit 13. Furthermore, when the reverse pulse is output, it is processed in the reverse flow error elimination circuit section as in the case of the first embodiment.

The reverse flow error elimination circuit section operates in the same manner as in the first embodiment, except that the number of pulses it handles is increased. In this embodiment, the counter 11 directly counts forward rotation pulses and reverse rotation pulses. , even if the pulse repetition frequency increases, it can cope with the increase.

In this embodiment (J:, the same applies to the first embodiment), it is also conceivable that the flip-flop circuit 15 is reset by a pulse output from the OR gate circuit 3. However, with this method, if the flow rate pulse frequently repeats forward and reverse rotation, a clear pulse will also be generated accordingly.

There is a problem in that the addition/subtraction calculations are not performed properly, and as a result, accurate output pulses cannot be obtained. Therefore, as described above, if the normal flow rate pulse output from the output terminal 14 of the AND gate circuit 13 is used to reset the flip-flop circuit 15, even if forward and reverse rotations are frequently repeated, , addition and subtraction operations can be performed normally.

Other Examples> The above-mentioned examples each show typical examples of the first and second inventions of the present application, and the first and second inventions of the present application are not limited to these.For example, The logic circuit is same-I! You can use other circuits as long as they can realize me.

[Effects of the Invention] As explained above, the present invention extracts high-resolution flow rate pulses with a simple configuration using logic circuits based on the A and B two-phase pulses output from one set of sensors A and B respectively. Moreover, since it can be carried out without particularly improving the part that forms the two-phase A and B pulses, it can be applied to already manufactured products. Further, the present invention can output accurate flow pulses by eliminating errors caused by reverse rotation of the rotor due to fluid pulsation.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing the configuration of a circuit that forms a flow rate pulse by applying the 51st embodiment of the flow rate pulse output method of the present invention;
Figures 2 and 3 are waveform diagrams showing the relationship between the forward and reverse rotation of pulses in the A and B phases and the phase, and Figure 4 is a waveform diagram showing the relationship between the A and B phase pulses and the phase.
, a waveform diagram showing the relationship between the B2 phase pulse and the flow rate pulse,
Fig. 5 is a time chart showing the operation of the inverse 1i and 1 error removal circuit section, Fig. 6 is an explanatory diagram showing an example of the part that forms the A and B two-phase pulses, and Fig. 7 is the flow rate pulse output method of the present invention. FIG. 2 is a circuit diagram showing the configuration of a circuit that forms a flow rate pulse by applying the second embodiment of the present invention. l...Flow path pipe 2...Flow meter 3.4.16...One-shot multivibrator 5
, 6... Inverter 7, 8.13... AND gate circuit 9.10.17.18... OR gate circuit 11...
Recenterable up/down counters 12, 15...7
Lip 70 tube circuits U1 to U4, DI-D4...Pulse forming unit Applicant: Oval Equipment Industry Co., Ltd. Agent: Patent attorney Iwao Mishina Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (4)

[Claims] (1) A flow rate pulse output method that forms and outputs a flow rate pulse based on two phase pulses, A and B, which are different in phase from each other and is output from a flow rate measurement unit in accordance with the position of the rotor, and the A-phase pulse. A and B during forward and reverse rotation of the rotor at the level of the B-phase pulse signal with respect to the rising edge of the signal and the level of the B-phase pulse signal with respect to the falling edge of the A-phase pulse signal.
A forward rotation pulse or a reverse rotation pulse with twice the pulse repetition frequency is formed respectively according to the combination determined by the phase lead/lag of the two-phase pulses, and if the formed pulse is a forward rotation pulse, The output gate is opened, and on the other hand, when the pulse formed above becomes a reverse pulse, the output gate is closed, and from now on,
A flow rate pulse output characterized by adding and subtracting forward rotation pulses and reverse rotation pulses, and when the number of forward rotation pulses exceeds the number of reverse rotation pulses, an output gate is opened and the above-mentioned forward rotation pulses are output as flow rate pulses. method. (2) A patent claim characterized in that the forward rotation pulse and the reverse rotation pulse are added/subtracted by an addition/subtraction counter with a reset function, and the reset command for the addition/subtraction counter is applied by applying the pulse output as the flow rate pulse. The flow rate pulse output method described in item 1. (3) A flow rate pulse output method in which a flow rate pulse is formed and outputted based on two phase pulses, A and B, which are different in phase from each other and are outputted from a flow rate measurement unit in accordance with the position of the rotor, and the A-phase pulse The level of the B-phase pulse signal with respect to the rising edge of the signal, the level of the A-phase pulse signal with respect to the rising edge of the B-phase pulse signal, the level of the B-phase pulse signal with respect to the falling edge of the A-phase pulse signal, and the falling edge of the B-phase pulse signal. A for
A forward rotation pulse or a reverse rotation pulse with a pulse repetition frequency of 4 times is generated according to the combination determined by the phase lead/lag of the A and B two-phase pulses during forward and reverse rotation of the rotor with respect to the level of the phase pulse signal. and if the formed pulse is a forward rotation pulse, the output gate is opened, while when the formed pulse is a reverse rotation pulse, the output gate is closed, and thereafter,
A flow rate pulse output characterized by adding and subtracting forward rotation pulses and reverse rotation pulses, and when the number of forward rotation pulses exceeds the number of reverse rotation pulses, an output gate is opened and the above-mentioned forward rotation pulses are output as flow rate pulses. method. (4) A patent claim characterized in that forward rotation pulses and reverse rotation pulses are added/subtracted by an addition/subtraction counter that is equipped with a reset function, and a reset command for the addition/subtraction counter is applied by applying a pulse outputted as the flow rate pulse. Flow rate pulse output method described in item 3.