EP4729778A1

EP4729778A1 - Pumping system, control unit and method for acquiring the number of revolutions of a rotative pump

Info

Publication number: EP4729778A1
Application number: EP25208526.1A
Authority: EP
Inventors: Stefano Bernardi; Lorenzo TEDESCHI; Costantino COCO; Giuseppe CARUSO
Original assignee: Comet SpA
Current assignee: Comet SpA
Priority date: 2024-10-21
Filing date: 2025-10-14
Publication date: 2026-04-22

Abstract

Method for acquiring the number of revolutions per minute N for a pump 100 of the rotary type, operating at a frequency f and having a number of pumping elements n, comprising the steps of:
- obtaining a raw pressure signal S1;
- normalizing the raw pressure signal S1 obtaining a clean pressure signal S2;
- obtaining an average pressure signal M from the clean pressure signal S2;
- identifying negative peaks Pn and positive peaks Pp of the clean pressure signal S2;
- obtaining a pulse train S3;
- normalizing the pulse train S3 for the frequency f and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100.

Computer program comprising instructions which, when the program is executed by a processing unit U, cause the computer to perform the steps of the acquisition method.

Control unit 10 for a pump 100 comprising:
a primary module 1, operatively connected to the pump 100, a secondary module 2 communicating with the primary module 1 by means of a communication system 3,
wherein the primary module 1 comprises a pressure sensor 11 configured to detect pressure values P of the pump 100 and to transmit a raw pressure signal S1, obtained from the pressure values P, to the secondary module 2, and
wherein the secondary module 2 comprises the processing unit U.
Pumping system 1000 comprising the pump 100 of the rotary type and the control unit 10.

Description

The present invention relates to the field of mechanical components for vehicles and motor vehicles, including, in particular, rotary pumps for distributing a fluid, in particular pure or supplemented water.
In particular, the present invention relates to instruments for monitoring the operation of rotary pumps.
Preferably, but not exclusively, the present invention relates to rotary pumps comprising only pistons or comprising piston and membrane systems.
Object of the present invention, in detail, is a method for acquiring the number of revolutions per minute of a rotary pump, usable in order to evaluate the operating conditions thereof.
A further object of the present invention is a computer program configured to perform said acquisition method.
A further object of the present invention is a control unit for a pump, comprising a processing unit configured to operate said computer program.
Finally, an object of the invention is also a pumping system comprising said control unit.
In the prior art, the operation of rotary pumps is monitored using a plurality of parameters.
In order to monitor the operation of a rotary pump, control units operatively connected to the pump and comprising revolution sensors configured to measure the number of revolutions per minute of the rotary pump are known: if the number of revolutions per minute is within a preset range, the rotary pump operates in optimal operating conditions, correctly distributing the fluid.
However, the revolution sensors of the prior art must be positioned at the shaft of the rotary pump in order to detect the number of revolutions of the pump. Therefore, their installation requires access to the rotation shaft, making the operations of installation, removal and replacement of the sensor burdensome, since the pump must be stopped and some components must be removed in order to access the aforementioned rotation shaft.
As a result, the control units of the prior art, in order to be able to monitor the operation of the pump, require operations of installation, removal and replacement of the sensors, and in particular of the revolution sensor, which are costly in terms of time and required interventions.
The technical task of the present invention is, therefore, to provide a method for acquiring the number of revolutions per minute of a rotary pump, a computer program for performing said method, a control unit for operating said method and a pumping system comprising said control unit, able to overcome the evident limitations of the prior art.
In particular, the object of the present invention is to provide an acquisition method, a computer program, a control unit and a pumping system that allow to acquire the number of revolutions per minute of a rotary pump quickly and effectively, without requiring access to the rotation shaft of the rotary pump.
The stated technical task and specified objects are achieved by an acquisition method, a computer program, a control unit and a pumping system comprising the technical features set forth in one or more of the appended claims.
Additional features and advantages of the present invention will emerge more clearly from the approximate and thus non-limiting description of a preferred but not exclusive embodiment of an acquisition method, a computer program, a control unit and a pumping system.
Such description will be set forth herein below with reference to the accompanying drawings, provided for merely indicative and therefore non-limiting purposes, wherein:

figure 1 shows a diagram representing in schematic form the acquisition method according to the present invention;
figure 2 shows a pumping system according to the present invention comprising a control unit connected to a pump of the rotary type. Reference numeral 100 indicates a pump of the rotary type, reference numeral 10 indicates a control unit operatively connected to the pump 100 and reference numeral 1000 overall indicates a pumping system comprising the pump 100 and the control unit 10 operatively connected to the pump 100.

A first object of the present invention is a pumping system 1000 comprising a pump 100, of the rotary type, and a control unit 10 for monitoring the pump 100.
Within the pumping system 1000 according to the present invention, the control unit 10 is operatively connected to the pump 100 (Fig. 2).
The control unit 10 is configured to perform a control of the pump 100. In particular, as we will see later, the control unit 10 is configured to detect operating parameters of the pump 100 and to compare said parameters with optimal operating ranges. The control unit 10 is, in fact, further configured to compare the values of the detected parameters with the respective optimal operating ranges and to signal when they are outside said ranges, or when the pump 100 is not operating under optimal conditions.
The pump 100 is of the rotary type, i.e. it comprises a rotation shaft around which a number n of pumping elements rotates at a frequency f: in other words, the pumping elements, for example pistons or piston and membrane systems, present in number equal to n, are configured to rotate around the rotation shaft, causing the pumping of a fluid through an outlet opening connected to a distribution conduit, in order to cause the distribution thereof to further components or compartments of the vehicle.
The fluid delivered by the pump 100 is preferably pure water or supplemented pure water.
Consequently, monitoring the operation of the pump 100 is essential to ensure optimal operating conditions of the pump 100 itself and, consequently, of the entire vehicle.
In order to monitor the operation of the pump 100, the pumping system 1000 then comprises the control unit 10, operatively connected to the pump 100.
The pumping system 1000 according to the present invention may further comprise a containment frame, not shown in the attached figures, made of vibration and shock-resistant material and suitable for containing and protecting the control unit 10. Thanks to the containment frame, the control unit 10 can be advantageously positioned at the motor of vehicles whose conditions of use are heavy, such as for example, but not limited to, agricultural vehicles. For example, the containment frame may be made of certified material to ensure a level of protection corresponding to IP68 grade.
A second object of the present invention is therefore the control unit 10 operatively connected to the pump 100.
The control unit 10 according to the present invention comprises a primary module 1, operatively connected to the pump 100, a secondary module 2 communicating with the primary module 1. In particular, the secondary module 2 is communicating with the primary module 1 by means of a communication system 3.
The primary module 1 comprises a pressure sensor 11 configured to detect pressure values P of the pump 100 and to transmit a raw pressure signal S1 to the secondary module 2.
For example, but not exclusively, the communication system 3 is configured to operate according to one or more of the following modes: radio frequency preferably at 433MHz, Wi-Fi, GSM 4G, LoRa, BLE, Canbus, Isobus, NFC. Other modes of communication or data transmission can be intuited by the person skilled in the art.
In other words, the raw pressure signal S1 is obtained from the pressure values P or, in still other words, the pressure sensor 11 is configured to acquire the pressure values P and to transduce them into the raw pressure signal S1.
The secondary module 2 comprises, in fact, a processing unit U, configured to receive in input the raw pressure signal S1 and to process said raw pressure signal S1.
At a higher level of detail, the processing unit U is configured to acquire the number of revolutions per minute N of the pump 100 starting from the raw pressure signal S1 and to compare said acquired number of revolutions per minute N with a preset revolution number control range. The method performed by the processing unit U to obtain the number of revolutions per minute N of the pump 100 starting from the raw pressure signal S1 will be illustrated in a later section of the present description. The processing unit U is finally configured to transmit a correct operation signal Sc, when the number of revolutions per minute N falls within the revolution number control range, or a non-correct operation signal Snc when the number of revolutions per minute N falls outside the revolution number control range.
Said correct operation signal Sc or said non-correct operation signal Snc can be transmitted to a signalling device 4 communicating with the secondary module 2.
Said transmission of the correct or non-correct operation signal Sc, Snc to the signalling device 4 can take place wirelessly.
In an embodiment of the pumping system 1000 according to the present invention, the control unit 10 comprises the signalling device 4 configured to receive the correct or non-correct operation signal Sc, Snc and to emit an acoustic, visual and/or auditory signal, dependent on the signal transmitted by the secondary module 2.
The signalling device 4 may in fact comprise a warning light, a loudspeaker for emitting an acoustic signal, a monitor, a display or other intuitive instrument.
Advantageously, the control unit 10 according to the present invention allows to detect and monitor the pressure value 10, to process the raw pressure signal S1 in order to obtain, according to the steps that will be described below, the number of revolutions per minute N of the pump, without necessarily having to comprise a revolution sensor to be coupled at the motor shaft of the pump 100.
The pressure sensor 11, in fact, must not be positioned at the pump shaft 100. Thus, unlike the revolution sensor, it does not require stopping or blocking the pump 100, removing one or more components to access the shaft, positioning the sensor, and subsequent repositioning of the removed components. The pressure sensor 11 can advantageously be positioned in a more peripheral portion of the pump 100 than the shaft, which is, due to the function performed, in a central or nuclear position.
The greater speed and greater convenience in the positioning of the pressure sensor 11, compared to the revolution sensor, make the control unit 10 according to the present invention easier to install and uninstall, compared to control units of the prior art described in the preamble of the description.
Finally, further advantageously, the pressure values P acquired by the pressure sensor 11 can be used not only to obtain the number of revolutions per minute N through the acquisition method according to the present invention, but also to obtain pressure information useful for monitoring the operation of the pump 100. For example, but not exclusively, the pressure values P, compared to a control pressure range, can be used to monitor the suction of the pumped fluid, preferably pure or supplemented water, entering the pump: pressure values outside the control range, and, in particular, depression values outside the control range, can indicate, for example, obstruction phenomena in a conduit for supplying the fluid to the pump 100.
Additionally, the primary module 1 of the control system 10 according to the present invention may comprise a temperature sensor 12, configured to detect fluid temperature values T inside the pump 100 and to transmit the temperature values T to the secondary module 2 and, in particular, to the processing unit U.
Therefore, the processing unit U is further configured to compare the temperature value T with a preset temperature control range and to transmit a correct operation signal Sc, when the temperature value T falls within the temperature control range, or a non-correct operation signal Snc when the temperature value T falls outside the temperature control range. In other words, the control unit 10 according to the present invention can be configured to monitor not only the number of revolutions per minute N, but also the temperature of the fluid contained in the pump 100, resulting in a more complete and accurate monitoring of the operation of the pump 100 itself.
Additionally or alternatively to the temperature sensor 12, the primary module 1 may comprise a level sensor 13, configured to detect internal fluid level L values of the pump 100 and to transmit the level L values to the secondary module 2 and, in particular, to the processing unit U.
In this case, then, the processing unit U is further configured to compare the level L value with a preset fluid level control range and to transmit a correct operation signal Sc, when the temperature value T falls within the fluid level control range, or a non-correct operation signal Snc when the level L value falls outside the fluid level control range.
Advantageously, the control unit 10 comprising a primary module 1 having the level sensor 13 allows to monitor the level of fluid inside the pump 100, signalling undesired fluid leakage or migration phenomena.
Fluid leakage or migration phenomena can, in fact, cause anomalies in other sectors, for example, in the lubrication circuit. In this case, the leakage of fluid into the lubrication circuit leads to an increase in the volume, comprising both lubricant and leaked fluid, therein. Conversely, oil leakage in the fluid supply circuit causes an emptying of the lubricant from the lubrication circuit.
In both cases, it is essential that the anomaly is detected and signalled as soon as possible, in order to intervene promptly to resolve existing faults.
Finally, in an alternative embodiment, not illustrated in the attached figures, the control unit 10 according to the present invention may also comprise a revolution sensor of the prior art, operating alternatively or in addition to the pressure sensor 11 and configured to detect the number of revolutions of the motor shaft of the pump 100. For example, but not exclusively, the revolution sensor may be activated in the event of a fault of the pressure sensor 11.
Summarizing and processing in other words, the processing unit U is configured to transmit the correct operation signal Sc when the number of revolutions per minute N is within the predetermined revolution number control range, when the primary module comprises only the pressure sensor 11. This configuration corresponds to a first embodiment of the control unit 10.
Alternatively, the processing unit U is configured to transmit the correct operation signal Sc when the number of revolutions per minute N is within the predetermined revolution number control range and when the temperature value T falls within the temperature control range, when the primary module comprises both the pressure sensor 11 and the temperature sensor 12. This configuration corresponds to a second embodiment of the control unit 10.
Alternatively, the processing unit U is configured to transmit the correct operation signal Sc when the number of revolutions per minute N is within the predetermined revolution number control range and when the level L values fall within the fluid level control range, when the primary module comprises both the pressure sensor 11 and the level sensor 13. This configuration corresponds to a third embodiment of the control unit 10. Finally, the processing unit U is configured to transmit the correct operation signal Sc when the number of revolutions per minute N is within the predetermined revolution number control range, when the fluid temperature value T is within the temperature control range, and when the level L values fall within the fluid level control range, when the primary module comprises both the pressure sensor 11, the temperature sensor 12, and the level sensor 13. The latter configuration corresponds to the fourth embodiment of the control unit 10 according to the present invention and is represented in Fig. 2.
Within the pumping system 1000 according to the present invention, the primary module 1 and the secondary module 2 can be connected to a power supply unit 5, arranged to provide the energy necessary for the operation of the primary and secondary modules 1, 2 and the components included therein. For example, but not exclusively, the power supply unit 5 may comprise a removable and replaceable battery.
Advantageously, the control unit 10 according to the present invention allows monitoring at least one parameter, namely the pressure value P of the pump 100, quickly and effectively detecting the presence of malfunctions and faults, in order to intervene promptly to prevent said malfunctions from lasting over time, ruining the pump 100 itself, the vehicle motor and/or other vehicle components.
Considering again the processing unit U of the control unit 10, a third object of the present invention is a method for acquiring the number of revolutions per minute N of the pump 100.
As stated above, the pump 100, of the rotary type, comprises a number n of pumping elements and operates at a frequency f: the pumping elements are configured to cause the pumping of the fluid, preferably pure or supplemented water, allowing the correct distribution thereof to further components.
With reference to the diagram of Fig. 1, the acquisition method according to the present invention comprises the steps of:

obtaining a raw pressure signal S1;
normalizing the raw pressure signal S1 obtaining a clean pressure signal S2;
obtaining an average pressure signal M from the clean pressure signal S2;
comparing the clean pressure signal S2 and the average pressure signal M, identifying negative peaks Pn and positive peaks Pp of the clean pressure signal S2;
extracting the negative peaks Pn and the positive peaks Pp, obtaining a pulse train S3;
normalizing the pulse train S3 for the frequency f and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100.

It should be noted that the detailed steps may be subject to changes that are intuitive to the person skilled in the art; moreover, the order of the steps shown is not to be considered binding.
Firstly, the method according to the present invention provides for the step of obtaining the raw pressure signal S1.
As shown above, the raw pressure signal S1 is obtained from the pressure values P detected by the pressure sensor 11. In particular, the raw pressure signal S1 has a wave, substantially periodic trend.
On the other hand, the raw pressure signal S1 is very noisy, i.e. disturbed. In order to make the signal cleaner or, in other words, less noisy, the method according to the present invention provides for the step of normalizing the raw pressure signal S1, obtaining the clean pressure signal S2. Normalization allows to intervene on the amplitude, or intensity, of the signal, by removing local disturbance elements that make said signal noisy.
Following normalization of the raw pressure signal S1, the clean pressure signal S2 is obtained, which has a periodic trend substantially similar to the raw pressure signal S1, but a variable amplitude in a different way with respect to the same.
In particular, normalization makes an average pressure signal M, i.e. a self-adapting average pressure signal M, more correctly identifiable, starting from the clean pressure signal S2.
The method according to the present invention, in fact, comprises the step of obtaining the average pressure signal M.
Furthermore, a substantially sinusoidal trend is detectable in the clean pressure signal S2, comprised between a range of positive peak values and a range of negative peak values.
By comparing the clean pressure signal S2 with the average pressure signal M it is therefore possible to identify a plurality of positive peaks Pp interspersed with a plurality of negative peaks Pn.
The positive peaks Pp and the negative peaks Pn can then be extracted, in order to obtain a pulse train S3.
Finally, the method according to the present invention provides for normalizing the pulse train S3 obtained for the frequency f and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100.
In detail, and in other words, the pulse train S3 is analysed, by extracting an average distance data item, i.e. the average distance between peaks of the pulse train S3.
The inverse of the obtained average distance between peaks allows to obtain the frequency of occurrence of the peaks and, consequently, the number of revolutions per minute N.
Advantageously, the method according to the present invention allows to obtain the number of revolutions per minute N of the pump 100 starting from a pressure data item, i.e. the pressure values P detected by the pressure sensor 11.
Advantageously, the method according to the present invention, applied to a control unit 10 of a pump 100 of the rotary type for the distribution of fluid, allows not to have to resort to positioning a revolution sensor at the shaft of the pump 100, but to obtain the number of revolutions per minute N indirectly.
This data item can be very advantageously used for monitoring the operation of the pump itself, for diagnosing malfunctions and for any further data processing.
The acquisition method according to the present invention may comprise, in one embodiment of the invention, the step of applying one or more filters F to the clean pressure signal S2, after the step of "normalizing the raw pressure signal S1 obtaining a clean pressure signal S2", in order to further clean the signal S2 to improve the signal processing performed in the subsequent steps. In particular, applying any additional filters F to the clean signal S2 allows the average pressure signal M to be obtained more accurately.
Finally, the acquisition method according to the present invention may comprise the further step of calculating the duration dt of each revolution, by measuring the distance between peaks within the train of peaks S3, after the step of "normalizing the pulse train S3 for the frequency F and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100".
In other words, by measuring the time distance between peaks in the pulse train S3 it is possible to obtain the duration dt of a revolution or part of a revolution, which may be useful as further data item to be used in monitoring and diagnostics of the operation of the pump 100.
The duration dt of each revolution can be compared with a distance between reference peaks or a control duration range, in order to detect malfunctions, which are signalled when the duration dt of each revolution does not correspond to the reference distance or does not fall within the control duration range.
The signals detected, transduced or transmitted by the pressure 11, temperature 12, level 13 sensors, the number of revolutions per minute N, the duration dt, the signals S1, S2, S3 processed in the steps of the method according to the present invention and/or other data or signals processed by the processing unit U can be allocated in an internal memory and/or sent to a remote server or a cloud network.
Consequently and in conclusion, the fourth object of the present invention is a computer program comprising instructions that cause the computer to perform the steps of the detailed acquisition method, when the program is executed by a computer comprising the processing unit U.
In other words, the processing unit U is comprised in a processor or a computer and a further object of the present invention is the computer program operated by said processing unit U: when operated by the processing unit U, the program according to the present invention is configured to perform the steps of the method for acquiring the number of revolutions per minute N of the pump 100.
Thanks to the computer program integrated into the processing unit U, the control unit 10 is advantageously able to detect the raw pressure signal S1 transduced by the pressure sensor 11 and to obtain the number of revolutions per minute N of the pump 10, following the steps comprised in the acquisition method according to the present invention.
Thanks to the computer program according to the present invention it is possible to transform a pressure information, i.e. the pressure values P or the raw pressure signal S1, into information on the number of revolutions per minute N. The number of revolutions per minute N is therefore obtainable without having to resort to a revolution sensor, which is more difficult to position and manage than a pressure sensor, as detailed in the previous paragraphs.

Claims

A method for acquiring the number of revolutions per minute N for a pump 100 of the rotary type, operating at a frequency f and having a number of pumping elements n, comprising the steps of:
- obtaining a raw pressure signal S1;

- normalizing the raw pressure signal S1 obtaining a clean pressure signal S2;

- obtaining an average pressure signal M from the clean pressure signal S2;

- comparing the clean pressure signal S2 and the average pressure signal M, identifying negative peaks Pn and positive peaks Pp of the clean pressure signal S2;

- extracting the negative peaks Pn and the positive peaks Pp, obtaining a pulse train S3;

- normalizing the pulse train S3 for the frequency f and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100.
The method according to claim 1, further comprising the step of:
- applying one or more filters F to the clean pressure signal S2, after the step of "normalizing the raw pressure signal S1 obtaining a clean pressure signal S2".
The method according to one of claims 1 or 2 further comprising the step of:
- calculating the duration dt of each revolution, by measuring the distance between peaks within the train of peaks S3, after the step of "normalizing the pulse train S3 for the frequency F and the number of pumping elements n, obtaining the number of revolutions per minute N of the pump 100".
A computer program comprising instructions which, when the program is executed by a computer comprising a processing unit U, cause the computer to perform the steps of the method according to at least one of claims 1-3.
A control unit 10 for a pump 100 comprising:
a primary module 1, operatively connected to the pump 100, a secondary module 2 communicating with the primary module 1 by means of a communication system 3,

wherein the primary module 1 comprises a pressure sensor 11 configured to detect pressure values P of the pump 100 and to transmit a raw pressure signal S1, obtained from the pressure values P, to the secondary module 2, and

wherein the secondary module 2 comprises a processing unit U, configured to perform the method of claims 1-3, by calculating the number of revolutions per minute N of the pump 100.
The control unit according to claim 5 wherein the processing unit U is further configured to:
- compare the number of revolutions per minute N of the pump 100 with a preset revolution number control range; and to

- transmit a correct operation signal Sc, when the number of revolutions per minute N falls within the revolution number control range, or a non-correct operation signal Snc when the number of revolutions per minute N falls outside the revolution number control range.
The control unit according to claim 5 wherein the primary module 1 further comprises a temperature sensor 12, configured to detect fluid temperature values T inside the pump 100 and to transmit the temperature values T to the processing unit U.
The control unit according to claim 7 wherein the processing unit U is further configured to:
- compare the temperature value T with a preset temperature control range; and to

- transmit a correct operation signal Sc, when the temperature value T falls within the temperature control range, or a non-correct operation signal Snc when the temperature value T falls outside the temperature control range.
The control unit according to one of claims 5 or 7, wherein the primary module 1 further comprises a level sensor 13, configured to detect internal fluid level L values of the pump 100 and to transmit the level L values to the processing unit U.
The control unit according to claim 9 wherein the processing unit U is further configured to:
- compare the level L value with a preset fluid level control range; and to

- transmit a correct operation signal Sc, when the temperature value T falls within the fluid level control range, or a non-correct operation signal Snc when the level value L falls outside the fluid level control range.
The control unit 10 according to at least one of the preceding claims comprising a signalling device 4 communicating with the secondary module 2 and configured to emit an acoustic, visual and/or auditory signal when the secondary module 2 transmits the non-correct operation signal Snc.
The control unit according to at least one of the preceding claims wherein the primary module 1 further comprises a revolution sensor connected to a motor shaft of the pump 100.
The control unit according to at least one of the preceding claims wherein the communication system 3 is configured to operate according to one or more of the following modes: radio frequency, Wi-Fi, 4G GSM, LoRa, BLE, Canbus, Isobus, NFC.
The control unit according to at least one of the preceding claims comprising a power supply unit 5 for the primary module 1 and the secondary module 2.
The control unit according to the preceding claim wherein the power supply unit 5 comprises a removable and replaceable battery.
A pumping system 1000 comprising a pump 100 of the rotary type and a control unit 10 for monitoring the pump 100 operatively connected to the pump 100, wherein the control unit 10 is of the type according to one or more of the preceding claims.