Measuring arrangement, flow meter and method for determining a non-continuous flow

Abstract

Measuring arrangement (1) for measuring a non-continuous flow of a fluid medium through a measuring tube (2), comprising a flow meter (3), an actuator (4) for generating a non-continuous flow, a communication link (5) and a control unit (6), wherein the actuator (4) and the flow meter (3) are arranged one after the other on the measuring tube (2) and wherein at least the actuator (4) and the control unit (6) are connected to each other via the communication link (5) such that the control unit (6) sends a control command to the actuator (4) to actuate the actuator (4) during operation, characterized by that the flow meter (3) has a control input (8), wherein the flow meter (3) is connected to the control unit (6) and / or the actuator (4) at least via the control input (8), wherein the flow meter (3) has a measuring phase during operation, wherein the flow meter (3) records flow measurement values ​​during the measuring phase, wherein, in the presence of a flow, the control input (8) of the flow meter (3) is supplied with a control signal which triggers the measuring phase, wherein the measuring arrangement is configured to carry out a method according to one of claims 8 to 15.

Description

[0001] The invention relates to a measuring arrangement for measuring a non-continuous flow of a fluid medium through a measuring tube, comprising a flow meter, an actuator for generating a non-continuous flow, a communication link and a control unit, wherein the actuator and the flow meter are arranged one behind the other on the measuring tube and wherein at least the actuator and the control unit are connected to each other via the communication link in such a way that the control unit sends a control command to the actuator to actuate the actuator during operation.

[0002] Furthermore, the invention relates to a flow meter with a control input for use in a measuring arrangement according to the invention, as well as a method for determining a non-continuous flow with a measuring arrangement according to the invention.

[0003] When measuring non-continuous flows, especially short flow pulses, limited sampling rates of flow meters can lead to situations where too few or no flow measurements are recorded at the moment of flow. This can occur, for example, if the sampling rate does not match the opening time of a valve. A limited sampling rate can result from factors such as the limited signal propagation time of ultrasonic signals when using ultrasonic flow meters, or from the inability to rapidly remagnetize and stabilize the magnetic field when using magnetic-inductive flow meters.

[0004] One way to resolve this problem is to increase the measurement rate. However, this is not always technically possible.

[0005] The object of the present invention is therefore to provide a measuring arrangement that ensures improved flow measurement of non-continuous flows. Furthermore, it is an object of the invention to provide a corresponding flow meter and a method for determining a non-continuous flow.

[0006] According to a first teaching of the invention, the problem is solved by a measuring arrangement mentioned above in that the flow meter has a control input, wherein the flow meter is connected to the control unit and / or the actuator at least via the control input, wherein the flow meter has a measuring phase during operation, wherein the flow meter records flow measurement values ​​during the measuring phase, where, in the presence of a flow, the control input of the flow meter is supplied with a control signal that triggers the measurement phase.

[0007] It was recognized that by triggering the measurement phase according to the invention at a time when a flow is present in the measuring tube of the measuring arrangement, it can be ensured that the flow is detected, even if it is only present in the form of a short flow pulse.

[0008] Even with limited measurement rates, this ensures that short flow pulses can be detected and that they do not overlap, or do not completely overlap, with, for example, a blind period of the flow meter that is technically necessary.

[0009] Advantageously, the measuring arrangement according to the invention can be used in applications where a medium is dispensed in metered pulses or splashes. Because the flow meter detects all flow pulses, it is possible to monitor and detect early, for example, if an actuator becomes clogged and thus no longer generates flow.

[0010] The control input of the flow meter can, for example, be configured as a trigger input. According to this configuration, during operation the control signal is sent as a trigger signal to the trigger input, which then initiates the measurement phase of the flow meter.

[0011] Alternatively, the flow meter can also be synchronized with the actuator's activation via the control input in such a way that if the actuator is activated with a control frequency, the flow meter's measurement phase is triggered at the same frequency. In this case, the control signal corresponds to the signal that informs the flow meter of the control frequency.

[0012] The measurement phase comprises the acquisition of at least one flow rate measurement. According to one embodiment, the measurement phase comprises the acquisition of exactly one flow rate measurement. According to another embodiment, the measurement phase comprises the acquisition of a plurality of flow rate measurements, which are preferably averaged for further evaluation.

[0013] According to a particularly preferred embodiment, the flow meter is designed and configured such that the measurement phase is triggered only by the control signal. According to this embodiment, the flow meter is therefore designed and configured such that no continuous measurement operation is carried out, but rather the acquisition of flow measurement values ​​is only event-driven.

[0014] In a further embodiment, the actuator is configured as a metering pump or metering valve. According to this embodiment, actuation or activation of the actuator refers to the opening of the metering valve or the activation of the metering pump. To open the metering valve or activate the metering pump, the control unit sends a control command to the metering valve or the metering pump. With the opening of the metering valve or the activation of the metering pump, flow begins through the measuring tube. During operation, the control input of the flow meter is then supplied with a control signal, triggering the measurement phase of the flow meter so that the flow rate can be measured.

[0015] According to a further advantageous embodiment, the control unit is configured to control the actuator during operation using PWM control. PWM control refers to pulse-width modulation control. Within this control system, the control command consists of a periodic sequence of a first voltage and a second voltage, whereby the actuator is activated when the first voltage is applied to it and deactivated when the second voltage is applied. According to this embodiment, a metering valve can be periodically opened or a metering pump can be periodically actuated during operation. For example, the first voltage can have a defined voltage value greater than zero, and the second voltage can be 0 V. The position of a metering valve can be adjusted via the value of the first voltage.Therefore, a metering valve can be opened with different valve opening degrees during operation.

[0016] According to a further preferred embodiment, an analog control line is provided between the actuator and the control input of the flow meter. According to this embodiment, during operation the actuator can directly send the control signal to trigger the measurement phase to the flow meter as soon as the actuator receives the control command to actuate the actuator from the control unit.

[0017] According to a further embodiment, an analog control line is provided between the control unit and the control input of the flow meter. In this embodiment, the control unit can, during operation, send both the control command to actuate the actuator and, preferably simultaneously, the control signal to trigger the measurement phase.

[0018] According to a further embodiment, a digital communication link exists between the actuator and the flow meter.

[0019] According to another preferred embodiment, a digital communication link is provided between the control unit and the flow meter.

[0020] The communication links between the actuator and / or the control unit and / or the control input of the flow meter can be either wired or wireless.

[0021] According to a further embodiment of the measuring arrangement, the flow meter is connected to the communication link between the control unit and the actuator and, during operation, detects control commands sent from the control unit to the actuator and triggers its measuring phase depending on the detected control commands. According to this embodiment, the actuator, the control unit, and the flow meter are connected in such a way that the flow meter listens to the communication between the control unit and the actuator.

[0022] According to a further embodiment, the actuator is regularly actuated by the control unit using a PWM controller with a control frequency during operation, the flow meter being configured such that the measuring phase is synchronized with the control frequency of the PWM controller. Such synchronization means that the measuring phase is triggered synchronously with the first voltage of the PWM controller, so that at least one flow measurement is recorded during each opening of the metering valve or each actuation of the metering pump.

[0023] According to a further embodiment, the flow meter can be designed such that it can be put into an energy-saving mode after the measurement phase and after the flow has ceased. In such an energy-saving mode, for example, part of the flow meter's internal electronics is switched off, so that the flow meter must first be activated before the next measurement phase can be triggered. According to one embodiment, a sensor can be provided for this purpose, which detects a state variable and, upon a change in the monitored state variable, sends a signal to activate the flow meter, thus putting the flow meter into a measurement-ready state. For example, such a sensor can be arranged internally within the flow meter or externally, on or in the measuring tube.The state variable detected by the sensor can be, for example, pressure, temperature, humidity, and / or flow rate. The sensor can therefore also be configured as a flow switch or a flow monitor.

[0024] According to a second teaching of the present invention, the problem set out at the beginning is solved by a flow meter described at the beginning with a control input for use in one of the previously described measuring arrangements.

[0025] The flow meter is preferably configured according to one of the previously described embodiments. Furthermore, the flow meter is also designed and configured to perform at least one of the methods described below.

[0026] According to a third teaching of the present invention, the problem mentioned at the outset is solved by a method described at the outset for determining a non-continuous flow rate with a measurement order according to the invention, in that the method comprises the following process steps: - Starting a flow by actuating the actuator based on a control command from the control unit, - Sending a control signal to the control input of the flow meter or receiving a control signal from the flow meter, thereby triggering the measurement phase of the flow meter, - Recording at least one flow rate measurement during the measurement phase by the flow meter, - Terminating the flow by actuating the actuator.

[0027] The method according to the invention has the advantage that the measuring phase of the flow meter is always triggered when the actuator is actuated. This design ensures that the flow generated by actuating the actuator is detected by the flow meter, even if this flow corresponds only to a short flow pulse.

[0028] In particular, it can be ensured that if the actuator is repeatedly opened briefly, so that flow pulses flow through the measuring tube at defined time intervals, all flow pulses can be recorded by the flow meter, since a separate measurement phase is triggered with each individual flow pulse.

[0029] According to a particularly preferred embodiment, in the case where the flow meter is connected to the communication link between the control unit and the actuator and detects control commands directed from the control unit to the actuator during operation, the detected control signal corresponds to the control command intercepted by the flow meter.

[0030] According to a further advantageous embodiment of the method, the flow meter is put into an energy-saving mode after the measurement phase and after the flow has ceased. It is particularly preferred that the flow meter be put into an energy-saving mode if the measurement phase has not been triggered for a defined period, for example, for 5 minutes. This embodiment has the advantage that, in cases where a flow is only generated intermittently, the flow meter is not permanently active, i.e., ready to trigger the measurement phase. This embodiment is therefore particularly energy-efficient.

[0031] Another embodiment of the method is characterized by the control unit controlling the actuator via PWM control, whereby the PWM control sends an alternating sequence of a first voltage and a second voltage to the actuator. The actuator is activated when the first voltage is applied and deactivated when the second voltage is applied. If the actuator is configured as a metering valve, activation of the actuator means that the valve is open. Deactivation consequently means that the metering valve is closed. If the actuator is configured as a metering pump, activation of the actuator means that the metering pump is generating a flow, and deactivation of the metering pump means that there is no flow.

[0032] According to this design, the actuator can be activated regularly, particularly periodically, during operation. The duration of the opening, i.e., the duration the actuator is subjected to the initial voltage, can vary. Furthermore, the ratio of activation to deactivation durations can also vary. For example, in one application, the actuator might be activated for 50% of a period and deactivated for 50%. In another application, however, the actuator might be activated for 70% of a period and deactivated for 30%. It is advantageous if the activation duration of the actuator remains constant across multiple measurement phases.

[0033] According to a further embodiment, the actuator is periodically activated via the PWM controller, whereby the measurement phase of the flow meter is synchronized with the first voltage of the PWM controller via the control input in such a way that at least one flow measurement is recorded with each activation of the actuator. This embodiment of the method also ensures that each individual flow pulse can be recorded in a sequence of several flow pulses.

[0034] According to one embodiment, a plurality of flow measurement values ​​are recorded during each activation, which are preferably averaged for further evaluation.

[0035] According to a particularly preferred embodiment, the periodic activation of the actuator generates flow pulses with a characteristic pulse profile, comprising the shape and length of the flow pulse. The flow meter determines the total volume of a flow pulse using the pulse profile and the at least one measured flow rate value of the flow pulse. According to this embodiment, the flow meter can not only register that a flow pulse is present, but also determine the total volume that flowed with the flow pulse. This embodiment allows for particularly precise determination of individual flow pulses.

[0036] According to one embodiment, the shape of a flow pulse is characterized, preferably when the metering valve is fully open, and in particular the relationship between the valve opening of the metering valve and the shape of a flow pulse, by at least one other faster measuring device.

[0037] Preferably, the shape of the flow pulse, in particular the relationship between valve opening and pulse shape, is stored in the flow meter.

[0038] According to one embodiment, the metering valve is designed such that the pulse shape is the same for different valve positions and only the height of the flow pulse varies with different valve positions.

[0039] Furthermore, to determine the total volume flowed with a flow pulse, it can also be generally assumed that the shape of the flow pulse is the same for different valve positions and only the height of the shape varies.

[0040] According to a further embodiment, the shape of a flow pulse generated by a metering pump, in particular the relationship between metering of the flow pulse and the pulse shape of the flow pulse, is characterized by a faster measuring device.

[0041] Preferably, the shape of the flow pulse, in particular the relationship between dosage and pulse shape, is stored in the flow meter.

[0042] The dosing pump is particularly preferably designed in such a way that the pulse shape is the same for different dosages and only the height of the flow pulse varies with different dosages.

[0043] Furthermore, to determine the total volume flowed with a flow pulse, it can generally be assumed that the shape of the flow pulse is the same for different dosages and only the height of the shape varies.

[0044] According to a further embodiment, in which the actuator is designed as a metering valve, the pressure of the medium in front of the metering valve is additionally taken into account to determine the pulse shape and / or the total volume flowed with a flow pulse.

[0045] For this purpose, a pressure sensor for determining the medium pressure is preferably arranged in front of the metering valve.

[0046] To take the pressure into account, for example, the pressure is also varied during the determination of the pulse shape with a fully open valve or during the characterization of the relationship between the valve opening and the pulse shape of the flow pulse, so that in the measurement phase, the pulse shape can be adjusted depending on the pressure measured by the pressure sensor.

[0047] Furthermore, the measuring setup can also be designed and operated in such a way that the pressure upstream of the metering valve is essentially constant. In this case, too, the pressure can be taken into account when determining the pulse shape. If the pressure corresponds to the medium pressure at which the pulse shape was characterized, the pulse shape does not need to be adjusted during the measurement phase. If the operating pressure deviates from the medium pressure at which the pulse shape was characterized, or if the characterization was performed at different pressures, the pulse shape determined from the flow measurement is adjusted during operation to the current pressure upstream of the metering valve.

[0048] For example, the pulse profile is designed such that the flow rate rises with a rising edge after actuator activation, resulting in a brief period of increased flow. This increased flow rate then falls, reaching a temporarily constant value in the form of a plateau, before falling again with a rising edge after actuator deactivation. The shape of the entire pulse profile can be interpolated by measuring at least one flow rate value at a defined time, corresponding to a defined point in the pulse profile. It is particularly preferred that at least one flow rate value from the plateau is recorded to reconstruct the pulse profile.

[0049] It is also preferred if the length of the flow pulses is fixed, and preferably constant, or if the flow meter is informed by the control unit or the actuator of the length of a flow pulse, which corresponds to the duration of the associated first voltage signal of the PWM control. Alternatively, the flow meter can be connected to the communication link between the control unit and the actuator and detect control commands directed from the control unit to the actuator, and derive the actuation time of the actuator and thus the length of the flow pulse from these detected control commands.

[0050] According to a particularly preferred embodiment, the measurement phase is triggered at a defined time of the flow pulse, wherein preferably the measurement phase is triggered with a defined time delay and wherein preferably the total flow of a flow pulse is calculated by acquiring a single flow measurement value with a known pulse profile.

[0051] If, during operation, the metering valve is controlled in such a way that it opens to a defined valve position, particularly fully, with each flow pulse, and the flow rate is always measured with the same time delay, the measured flow rate will, as expected, be essentially constant. A deviation in the measured flow rate over several flow pulses can, for example, indicate a blockage of the metering valve. This is especially true if there are no pressure fluctuations upstream of the metering valve.

[0052] According to a further embodiment, in a measurement phase a plurality of flow measurement values ​​can also be sampled at each defined point of the pulse profile, which can further improve the interpolation of the flow pulse and thus the determination of the total flow of a flow pulse.

[0053] There are now numerous possibilities for designing and further developing the measuring arrangement, the flow meter, and the method according to the invention. Reference is made to the following description of preferred embodiments in combination with the drawing. The drawing shows Fig. 1 a first embodiment of a measuring arrangement, Fig. 2 another embodiment of a measuring arrangement, Fig. 3 another embodiment of a measuring arrangement, Fig. 4 another embodiment of a measuring arrangement, Fig. 5 a representation of the PWM control of a metering valve in combination with the flow pulses through the metering valve, Fig. 6 an embodiment of a method for determining a non-continuous flow rate, Fig. 7 another embodiment of a method for determining a non-continuous flow rate, Fig. 8 a further embodiment of a method for determining a non-continuous flow rate and Fig. 9 another embodiment of a method for determining a non-continuous flow rate.

[0054] Fig. Figure 1 shows a first embodiment of a measuring arrangement 1 for measuring a non-continuous flow rate of a fluid medium through a measuring tube 2, comprising a measuring tube 2, a flow meter 3, an actuator 4 for generating a non-continuous flow rate, a communication link 5, and a control unit 6. The actuator 5 and the flow meter 3 are arranged one behind the other on the measuring tube 2 in the direction of flow. Furthermore, the actuator 4 and the control unit 6 are connected to each other via the communication link 5 such that, during operation, the control unit 6 sends a control command to the actuator 4 to actuate it. In detail, in the illustrated embodiment, the actuator 4 is designed as a metering valve 7.

[0055] The flow meter 3 also has a control input 8, via which the flow meter 3 is connected to the control unit 6 in the illustrated embodiment.

[0056] Furthermore, the flow meter 3 is designed and set up in such a way that it has a measurement phase during operation in which the flow meter 3 records flow measurement values.

[0057] Opening the metering valve 7 allows a flow through the measuring tube 2. When a flow is present, the control input 8 of the flow meter 3 is supplied with a control signal, which triggers the measurement phase.

[0058] In detail, the control unit 6 controls the metering valve 7 via a PWM controller, whereby a periodic signal consisting of an alternating sequence of a first voltage 9 and a second voltage 10 is transmitted to the metering valve 7. The metering valve 7 is open when the first voltage 9 is applied to the metering valve and the metering valve 7 is closed when the second voltage 10 is applied to the metering valve 7.

[0059] During operation, the control unit 6 simultaneously sends a control signal to the control input 8 of the flow meter 3 along with the control command comprising the first voltage 9, which triggers the measurement phase.

[0060] The illustrated measuring arrangement 1 therefore has the advantage that particularly time-limited flows, such as dosing sprays, can be recorded with exceptional reliability.

[0061] Optionally, the flow meter 3 is put into an energy-saving sleep mode if it has not been put into the measurement phase for a specified period of time, for example for a period of 5 minutes.

[0062] In Fig. Figure 2 shows another embodiment of a measuring arrangement 1. In contrast to the one in Fig. In the embodiment shown in Figure 1, the flow meter 3 is not connected to the control unit 6 via a separate line. Instead, the flow meter 3 and the metering valve 7 are connected to the control unit 6 via a common fieldbus. In this example as well, the control unit 6 sends a control signal to the flow meter 3 during operation to trigger the measurement phase when it sends a corresponding control command to open the metering valve 7.

[0063] Fig. Figure 3 shows a further embodiment of the measuring arrangement 1, wherein the metering valve 7 is connected to the control unit 6 via a line and wherein the metering valve 7 is further connected to the control input 8 of the flow meter 3 via another line. During operation, the metering valve 7 sends a control signal to the flow meter 3 to trigger the measuring phase when it receives a control command to open the metering valve 7 from the control unit 6.

[0064] According to the in Fig. In the exemplary embodiment of a measuring arrangement 1 shown in Figure 4, the flow meter 3 is connected to the communication link 5 between the control unit 6 and the metering valve 7 in such a way that it detects control commands directed from the control unit 6 to the metering valve 7 and triggers its measuring phase depending on the detected control commands. According to this configuration, a control signal is not actively sent to the flow meter 3 during operation; rather, the flow meter 3 receives the information, i.e., the control signal, to trigger the measuring phase by listening to the communication between the control unit 6 and the metering valve 7.

[0065] All in the Fig. The communication links shown in Figures 1 to 4 can be based on either analog or digital data transmission. Furthermore, the communication links can be either wired or wireless.

[0066] Furthermore, the metering valve 7 can also be replaced by a metering pump in all embodiments.

[0067] In Fig. Figure 5 shows the flow behavior through the measuring tube 2 in the case of PWM control of the metering valve. The PWM control comprises the transmission of a sequence of a first voltage 9 and a second voltage 10 to the metering valve 7, wherein the metering valve 7 is open when the first voltage 9 is applied to the metering valve 7 and wherein the metering valve 7 is closed when the second voltage 10 is applied to the metering valve 7.

[0068] If the metering valve 7 is opened, particularly briefly, a flow pulse is generated, which is characterized by a characteristic pulse profile 11, comprising the shape and length of a flow pulse.

[0069] In the illustrated embodiment, the flow pulse is characterized first by a brief increase in flow rate and then by a time-limited constant flow rate. When the metering valve 7 is opened, the measurement phase is triggered with a time delay, ensuring that the flow measurement takes place when the flow rate reaches a value on the constant flow rate plateau. In the illustrated embodiment, the flow rate is determined at times t1 and t2.

[0070] If the characteristic pulse profile 11 is known, then, in addition to the basic detection of a flow pulse, the total volume flowing with the flow pulse can also be determined. Such a design has the advantage that, even by measuring a single flow value, the total volume flowing with a flow pulse can be determined by interpolating the pulse profile. Optionally, the medium pressure prevailing upstream of the metering valve is also taken into account to determine the pulse profile 11 from the measured flow value. By considering this factor, the pulse profile 11 can be determined with particular accuracy.

[0071] In Fig. Figure 6 is an embodiment of a method 12 for determining a non-continuous flow rate using one of the methods described in the Fig. Measurement orders 1 to 4 are shown.

[0072] The procedure comprises the following steps: - Starting 13 of a flow by opening the metering valve 7 by a control command from the control unit 6, - Sending 14 a control signal to the control input 8 of the flow meter 3 or detecting 15 a control signal by the flow meter 3, thereby triggering the measuring phase of the flow meter 3, - Capture 16 of at least one flow measurement value during the measurement phase by the flow meter 3, - Ending the flow by closing the metering valve 7.

[0073] This method 12 has the advantage that even short-term flow pulses can be detected by the flow meter 3, since a new measurement phase is triggered with each flow pulse.

[0074] Fig. Figure 7 shows a further embodiment of a method 12, wherein, in addition to detecting flow pulses according to method steps 13 to 17, the total volume flowing per flow pulse is also determined 18. For this purpose, the length of a flow pulse is known to the flow meter 3, either because the length is constant, or because the flow meter 3 receives information about the duration of the opening of the metering valve 7. In addition, the shape of the flow pulse is also stored in the flow meter 3.

[0075] Based on the knowledge of the pulse profile 11 and a measured value of the flow rate during the flow pulse at a defined time, the flow meter 3 can interpolate the actual flow pulse and thus determine the total volume that flowed during a flow pulse.

[0076] In Fig. Figure 8 shows a further embodiment of a method 12 for determining a non-continuous flow rate.

[0077] The illustrated embodiment includes the additional process step that the flow meter 3 is placed in an energy-saving standby mode 19 after the flow has ceased, if the measurement phase is not triggered for a specified period. While the flow meter is in energy-saving mode, part of the internal electronics of the flow meter 3 is switched off, so that the flow meter 3 must first be activated before the next measurement phase can be triggered. Thus, the method 12 and the design of the flow meter 3 are particularly energy-efficient, ensuring long battery operation.

[0078] Fig.Figure 9 shows a further embodiment of a method 12 for determining a non-continuous flow rate, wherein, after the flow rate 17 has ceased, the total volume of the flow pulse 18 is first determined, and wherein the flow meter is subsequently placed in an energy-saving standby mode 19 if the measurement phase is not triggered for a defined period. Such a method has the advantage that it is possible not only to monitor whether a flow pulse is generated each time the valve opens, but also whether the expected total volume flows. Furthermore, it ensures particularly energy-efficient operation of the flow meter 3, since the flow meter 3 only needs to be fully ready to measure when a flow rate is expected. Reference sign 1 Measuring setup 2 measuring tubes, 3 Flow meter 4 Actuator 5 Communication link 6 Control unit 7 Metering valve 8 Control input 9 first tension 10 second voltage 11 Pulse profile 12 methods for determining a non-continuous flow 13 Starting a flow 14 Sending a control signal 15. Capturing a control signal 16. Recording at least one flow measurement 17. Ending the flow 18 Determination of the total volume 19. Putting into energy-saving mode

Claims

[1] Measuring arrangement (1) for measuring a non-continuous flow of a fluid medium through a measuring tube (2), comprising a flow meter (3), an actuator (4) for generating a non-continuous flow, a communication link (5) and a control unit (6), wherein the actuator (4) and the flow meter (3) are arranged one after the other on the measuring tube (2) and wherein at least the actuator (4) and the control unit (6) are connected to each other via the communication link (5) such that the control unit (6) sends a control command to the actuator (4) to actuate the actuator (4) during operation, characterized by , that the flow meter (3) has a control input (8), wherein the flow meter (3) is connected to the control unit (6) and / or the actuator (4) at least via the control input (8), wherein the flow meter (3) has a measuring phase during operation, wherein the flow meter (3) records flow measurement values ​​during the measuring phase, wherein, in the presence of a flow, the control input (8) of the flow meter (3) is supplied with a control signal which triggers the measuring phase, wherein the measuring arrangement is configured to carry out a method according to one of claims 8 to 15. [2] Measuring arrangement (1) according to claim 1, characterized by that the actuator (4) is designed as a metering pump or metering valve (7). [3] Measuring arrangement (1) according to one of claims 1 or 2, characterized by , that the control unit (6) is set up such that it controls the actuator (4) during operation by means of a PWM control. [4] Measuring arrangement (1) according to one of claims 1 to 3, characterized by, that an analog control line exists between the actuator (4) and the control input (8) of the flow meter (3) and / or between the control unit (6) and the control input (8) of the flow meter (3). [5] Measuring arrangement (1) according to one of claims 1 to 4, characterized by , that a digital communication link exists between the actuator (4) and the flow meter (3) and / or between the control unit (6) and the flow meter (3). [6] Measuring arrangement (1) according to any one of claims 1 to 5, characterized by , that the flow meter (3) is connected to the communication link (5) between the control unit (6) and the actuator (4) and receives control commands directed from the control unit (6) to the actuator (4), and triggers its measurement phase depending on the received control commands. [7] Flow meter (3) with a control input (8) for use in a measuring arrangement (1) according to any one of claims 1 to 6. [8] Method (12) for determining a non-continuous flow using a measuring arrangement (1), wherein the measuring arrangement comprises a flow meter (3), an actuator (4) for generating a non-continuous flow, a communication link (5) and a control unit (6), wherein the actuator (4) and the flow meter (3) are arranged one after the other on the measuring tube (2) and wherein at least the actuator (4) and the control unit (6) are connected to each other via the communication link (5) such that the control unit (6) sends a control command to the actuator (4) to actuate the actuator (4) during operation, wherein the flow meter (3) has a control input (8), wherein the flow meter (3) is connected at least via the control input (8) to the control unit (6) and / or the actuator (4), wherein the flow meter (3) has a measuring phase during operation, wherein the flow meter (3) records flow measurement values ​​during the measuring phase, wherein, in the presence of a flow, the control input (8) of the flow meter (3) is supplied with a control signal which triggers the measuring phase, characterized by the following procedural steps: - Starting (13) a flow by actuating the actuator (4) based on a control command from the control unit (6), - Sending (14) a control signal to the control input (8) of the flow meter (3) or receiving (15) a control signal from the flow meter (3), thereby triggering the measurement phase of the flow meter (3), - Recording (16) at least one flow measurement value during the measurement phase by the flow meter (3), - Termination (17) of the flow by actuating the actuator (4) and, that the flow meter (3) is put into an energy-saving mode after the measurement phase and after the flow has ended (19) and / or that the actuator (4) is regularly actuated by the control unit (6) by means of a PWM control with a control frequency and that the flow meter (3) is set up such that the measuring phase is synchronized with the control frequency of the PWM control. [9] Method (12) according to claim 8, characterized by that the detected control signal corresponds to the control command heard by the flow meter. [10] Method (12) according to any one of claims 8 to 9, characterized by, that the control unit (6) controls the actuator (4) by means of a PWM control, wherein the PWM control sends an alternating sequence of a first voltage and a second voltage to the actuator (4), wherein the actuator (4) is activated when the first voltage is applied to the actuator (4) and wherein the actuator (4) is deactivated when the second voltage is applied to the actuator (4). [11] Method (12) according to claim 10, characterized by , that the actuator (4) is periodically activated via the PWM control and that the measuring phase of the flow meter (3) is synchronized with the first voltage of the PWM control via the control input (8) such that at least one flow measurement is recorded each time the actuator (4) is activated. [12] Method (12) according to claim 11, characterized by, that by periodic activation of the actuator (4) flow pulses with a characteristic pulse profile (11), comprising the shape and length of the flow pulse, are generated and that the flow meter (3) determines the total volume of a flow pulse using the pulse profile (11) and the at least one measured flow value of the flow pulse (18). [13] Method (12) according to claim 12, characterized by , that the shape of the flow pulse, in particular the relationship between valve opening or metering and pulse shape, is stored in the flow meter, and that the determination of the shape of the flow pulse is based on the at least one measured flow value, in particular wherein, in the case where the actuator (4) is designed as a metering valve, the pressure of the medium upstream of the metering valve is also taken into account. [14] Method (12) according to claim 12 or 13, characterized by, that the length of the flow pulses is fixed, and preferably constant, or that the flow meter is informed of the length of a flow pulse, which corresponds to the duration of the associated first voltage signal. [15] Method (12) according to any one of claims 8 to 14, characterized by that the measurement phase is triggered at a defined time point of the pulse profile, wherein preferably the measurement phase is triggered with a defined time delay and wherein preferably the total flow rate of a flow pulse is calculated by capturing a single flow measurement value with a known pulse profile.

Images