Module for Detecting the Angular Position of the Drive Shaft of a Valve, Valve and Actuator Provided with such Module, and Method of Detecting the Opening of a Valve

Abstract

A module for detecting the angular position of the drive shaft of a valve includes a printed circuit proximate a drive shaft of a valve body, or of an extension element thereof or a motor shaft of a valve actuator. The module also includes a magnet(s) fastened to the drive shaft, a magnetic sensor(s) supported on the printed circuit, and a communication interface. The magnetic sensor(s) generate an electrical signal indicating the position of the magnet(s). The communication interface remotely transmits a corresponding reading. The acquisition of the reading can be carried out at pre-set time intervals, which can be managed according to the requirements of the production process. The detection module is free of wired connections with the outside. A valve and an adapter element are also provided with the module, and a method for detecting the open state of the valve remotely by the module.

Claims

1-21. (canceled)

22. An actuator of a valve, comprising a box-like body, a motor shaft and a thrust mechanism which are housed in the box-like body, wherein the motor shaft protrudes outwardly from the box-like body and can be connected to the drive shaft of a valve to be actuated, and wherein the motor shaft is rotatable on its longitudinal axis in response to the stresses imparted by the thrust mechanism and comprises one or more magnets, characterised by comprising a detection module for detecting the angular position of the motor shaft, comprising at least one printed circuit which can be positioned in the proximity of the motor shaft, one or more magnetic sensors supported on the printed circuit, a communication interface, wherein the magnetic sensors generate an electrical signal indicative of the position of said magnets, and the communication interface remotely transmits a corresponding signal, or reading, wherein the detection module is free of wired connections with the outside and is self-powered by at least one battery, and wherein the detection module is positioned at the height of the magnets, in a pocket of the box-like body, and is insulated from the motor shaft and the thrust mechanism.

23. The actuator according to claim 22, wherein the thrust mechanism comprises an electric motor, or one or more pneumatic pistons that can be moved in corresponding cylinders, which can be fed with compressed air.

24. The actuator according to claim 22, wherein the magnets are fastened to the motor shaft with circumferential arrangement, at a motor shaft portion inserted in a hole passing through a wall of the box-like body and the pocket housing the module is separated from said through hole by a portion of the box-like body, so that the magnetic sensors detect the position of the magnets through said portion of the box-like body.

25. The actuator according to claim 22, wherein the detection module is inserted in the respective pocket of the box-like body in a water-tight and/or flush manner.

26. The actuator according to claim 22, wherein the battery is a coin-cell battery and the at least one printed circuit has, on a plan view, dimensions substantially corresponding to those of the battery.

27. The actuator according to claim 26, wherein the battery has a diameter of less than 3 cm.

28. The actuator according to claim 22, further comprising a processing unit for processing the signal generated by the magnetic sensors and/or a memory in which the readings taken are stored.

29. The actuator according to claim 28, wherein the processing unit and the communication interface are the same unit.

30. The actuator according to claim 22, wherein the communication interface is wireless and can be interfaced with a remote router with a radio communication protocol.

31. The actuator according to claim 22, comprising at least one latch magnetic sensor and one triaxial magnetic sensor.

32. The actuator according to claim 22, comprising two printed circuits positioned on opposite sides with respect to the battery, wherein the magnetic sensors are constrained to the printed circuit which is located on the opposite side of the battery with respect to the printed circuit carrying the communication interface and are electrically connected to the communication interface.

33. The actuator according to claim 22, comprising at least one photodiode powered by the battery and connected to the communication interface and/or connected to a memory, and wherein the detection module is housed in an enclosure or in a pocket closed by a cover, and the photodiode generates an electrical alarm signal in the circumstances the enclosure or the cover is tampered with and the photodiode detects a change in brightness.

34. The actuator according to claim 22, comprising program means, for example incorporated in the transmission interface, which are programmed to remotely send an alarm signal in the event of an attempt to tamper with the detection module or alter the readings by means of outer magnetic fields, and/or comprises a memory in which to store the tampering attempt occurred.

35. The actuator according to claim 22, comprising an enclosure in which all the components are inserted, and in which the enclosure can be completely inserted in said in a pocket of the box-like body, or can be inserted flush with said housing/pocket, so as not to protrude with respect thereto.

36. A method for detecting the open state of a fluid valve equipped with a valve body and a corresponding drive shaft, the method comprising: a) positioning a plurality of magnets on a motor shaft of a valve actuator and connecting said motor shaft of the actuator to said drive shaft of the fluid valve; b) positioning, in the proximity of the motor shaft of the actuator, at the height of the magnets, a detection module comprising at least one printed circuit, one or more magnetic sensors supported on the printed circuit, a communication interface, c) by means of the magnetic sensors, generating an electrical signal indicative of the position of said magnets; d) by means of the communication interface, transmitting a corresponding signal, or reading, to a remote router; and e) equipping the detection module with a battery for powering its components and carrying out steps c) and d) in wireless mode.

37. the method according to claim 36, wherein step d) is optionally preceded by a step, carried out directly by the communication interface, of processing the electrical signal generated by the magnetic sensors.

38. The method according to claim 36, wherein step b) is carried out by inserting the detection module into a corresponding pocket obtained in the valve or box-like body of the respective actuator, insulated from the drive shaft or the motor shaft and also insulated from other components of the valve or actuator, and preferably without protruding outwardly.

39. The method according to claim 36, comprising: f′) detecting an attempt at physical tampering of the detection module by means of at least one photodiode powered by a battery and connected to the communication interface and/or connected to a memory, and wherein the detection module is housed in an enclosure and the photodiode generates an electrical alarm signal in the circumstance the enclosure is tampered with and the photodiode (16) detects a change in brightness, and/or f″) detecting an attempt to tamper with the detection module, accomplished by means of outer magnetic fields, wherein the communication interface processes the electrical signals generated by the magnetic sensors and detects anomalies caused by outer magnetic fields, and generates a corresponding alarm signal.

Description

BRIEF LIST OF THE FIGURES

[0073] Further characteristics and advantages of the invention will be better highlighted by examining the following detailed description of its preferred, but not exclusive, embodiments depicted by way of non-limiting example, with the support of the appended drawings, wherein:

[0074] FIG. 1 is an exploded view of a module for detecting the angular position of the drive shaft of a valve, according to the present invention;

[0075] FIG. 2 is a perspective view of the module shown in FIG. 1;

[0076] FIG. 3 is a perspective view of a first manual valve provided with a module according to the present invention;

[0077] FIG. 4 is a perspective view of a second manual valve provided with a module according to the present invention;

[0078] FIG. 5 is a perspective view of a third manual valve provided with a module according to the present invention;

[0079] FIG. 6 is a perspective view of an electric actuator for actuating a valve, provided with a module according to the present invention;

[0080] FIG. 7 is a perspective view of a first pneumatic actuator for actuating a valve, provided with a module according to the present invention;

[0081] FIG. 8 is a perspective and partially vertical sectional view of the actuator shown in FIG. 7;

[0082] FIG. 9 is an enlarged view of a portion of FIG. 8;

[0083] FIG. 10 is a perspective and partially vertical sectional view of a second pneumatic actuator for actuating a valve, provided with a module according to the present invention;

[0084] FIG. 11 is an enlarged view of a portion of FIG. 10;

[0085] FIG. 12 is a horizontal sectional view of a portion of the actuator shown in FIG. 10;

[0086] FIG. 13 is a perspective and partially exploded view of a third pneumatic actuator for actuating a valve, provided with a module according to the present invention;

[0087] FIG. 14 is a schematic view of a network of valves and actuators according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[0088] FIG. 1 shows in an exploded view a detection module 1 according to the present invention, from now on simply “module” 1, and FIG. 2 shows the module 1 assembled. The module 1 comprises at least one first printed circuit 2 and preferably also a second printed circuit 3, which are positioned on opposite sides with respect to a compact battery 4, for example a CR2450-type (IEC code) coin-cell battery having a diameter of 24.5 mm and a thickness of 5 mm; it is a type of battery frequently used in portable devices that require high current (30 mA) and long life (months or years).

[0089] The battery 4 is kept in contact with the first printed circuit 2 by a metal battery-holding plate 5, which makes the electric contact with the negative pole and snap-fits on the first printed circuit 2, where there are other electric contacts for the positive pole.

[0090] The first printed circuit 2 and the second printed circuit 3 are constrained to each other, and electrically connected, by means of pins 6 and spacers 7.

[0091] If necessary, unless a specific enclosure is used, the module 1 is screwed to a valve for fluids, or to another device, such as an adapter or an actuator, by means of screws 8 and spacers 9.

[0092] The module is intended to interact with magnets of the instruments to which the module must be applied (not visible in FIGS. 1 and 2) and comprises magnetic sensors 10 and 11, a communication interface 12 and preferably also a memory 13, for example a flash memory card.

[0093] Preferably, a first magnetic sensor 10 is of triaxial type and a second magnetic sensor 11 is of latch type. The magnetic sensors 10 and 11 are positioned at an edge of the respective printed circuit 2, 3, so as to face the magnets when the module 1 is in operation.

[0094] In the embodiment shown in the figures, the magnetic sensors 10 and 11 are mounted on the second printed circuit 3 and the communication interface 12 and the memory card 13 are mounted on the first printed circuit 2, on the opposite side with respect to the battery 4. This configuration makes the module 1 particularly compact, considering that the overall dimensions are little greater than the dimensions of the battery 4 alone. In fact, the solution shown in FIGS. 1 and 2 has dimensions of about 30×30×10 mm and this makes the module 1 easily and physically integrable in the valve for fluids or in the actuators, even the existing ones, as an accessory to be installed in retrofit.

[0095] The communication interface 12 is powered by the battery 4 and is of the wireless radio type, i.e. it transmits radio signals in accordance with known protocols, for example toward a remote router of a company network.

[0096] In general, the battery 4 powers all the components of the module 1, meaning that the module 1 is self-sufficient and does not require wired connections with the outside, both as regards the electric power supply and as regards the remote transmission of the signals generated by the magnetic sensors 10, 11.

[0097] In FIGS. 1 and 2 the module 1 is shown, for the sake of simplicity, without a containment enclosure: it is one of the possible configurations, ready to be inserted in a suitable compartment or a pocket obtained in a valve or in an actuator, for example, in the proximity of the magnets of the valve or actuator.

[0098] FIG. 3 shows a possible application: it is a valve 100 for fluids, provided with an (inner) valve body 102 that is rotatable in the base 104 together with the respective drive shaft 101 that is also rotatable inside the extension element 106, which is long sufficiently to protrude out of the base enough to allow the installation of the module 1. The module 1, which is boxed in a protective enclosure 14, is fastened at the drive shaft 101, at the height of the magnets (not visible). The magnets were fastened to the drive shaft 101 and made integral with it during the manufacturing step of the valve 100, or even later, during an overhaul operation. The drive shaft 101 is rotatable on its longitudinal axis with a lever 103, that is the valve 100 is manual. For convenience, the enclosure 14 can be made integral with the drive shaft 101 together with the lever 103, i.e. by using the same bolt 105.

[0099] Basically, the valve 100 can be made new already provided with the module 1, to be used in an industrial site in which the open state of the valve 100 can be controlled remotely, by interrogating the module 1 remotely, for example by connecting the module 1 to a router of a control network.

[0100] Alternatively, the module 1 can also be installed on an existing valve 100, taking care to upgrade the drive shaft 101 with the installation of the magnets.

[0101] FIG. 4 shows another manual valve 200, similar to the valve 100 shown in FIG. 3. The valve 200 is also actuated by a lever 203. Unlike the valve 100, the drive shaft of the valve 200 is short, meaning that it does not protrude from the respective base by a length sufficient to install the module 1. In this circumstance, an extension element 300, i.e. an adapter, is mounted on the valve 200, which comprises its own shaft 301 that extends the drive shaft of the valve 200, offering the possibility of installing a module 1. The adapter 300 is particularly useful and convenient for being able to equip existing valves with the module 1: in fact, in the conditions in which it would be difficult or uneconomical to disassemble an existing valve to fasten the magnets on the respective drive shaft, it is possible to use the adapter 300, whose shaft 301 can be originally provided with the magnets. In a few minutes it is therefore possible, by means of a bracket 302, to mount the module 1 and make it operative: since the shaft of the adapter 300 is made integral with the drive shaft of the valve, any possible rotations imparted to the valve body are detected as identical by the module 1 on the shaft 301.

[0102] The extension element, or adapter 300, is basically a valid aid for the aftermarket installation of the module 1 on existing valves.

[0103] FIG. 5 shows still another application example: a manual valve 400 operated by a handwheel 403 through a reducing mechanism 404. The module 1 is installed at the drive shaft 401, which connects the reducing mechanism 404 to the valve body inside the base. Also in this circumstance, the magnets of module 1 can be fastened originally on the drive shaft 401, or at a later time, even if less practical.

[0104] FIG. 6 shows yet another application: an electric actuator 500, which can be functionally coupled to a valve 100, 200, 300 to automate its operation, i.e. to be able to control the valve to remotely open and close. The electric actuator 500 is contained in a box-like housing 502 in which the module 1 is also contained, in a pocket or compartment 503. The module 1 is positioned adjacent to the motor shaft 501 and with the magnetic sensors 10, 11 facing it precisely. The motor shaft 501 is originally provided with magnets: in the assembled configuration, the module 1 is located just at the height of the magnets positioned on the shaft 501.

[0105] FIG. 7 shows a pneumatic actuator 600 equipped with module 1. The module 1 is completely contained in a pocket or compartment 603 of the box-like enclosure 602 of the actuator 600, in the proximity of the motor shaft 601 but separated therefrom. In particular, the pocket 603 is insulated both on the inside of the actuator 600, where the pneumatic thrust mechanism fed with compressed air is present, and on the outside, when it is closed by a cover 14′ possibly equipped with a gasket.

[0106] FIG. 8 shows the same actuator 600 in a partially sectional view: it is possible to see the inside of the actuator 600 and, in particular, the motor shaft 601 and the respective thrust mechanism 604, comprising pneumatic pistons 605 which can be moved reciprocatingly in corresponding cylinders 606 fed with compressed air supplied from the outside, according to a configuration known in the art by the name Scotch-Yoke (slotted-link mechanism).

[0107] FIG. 9 is an enlargement of FIG. 8, in particular of the portion comprising the motor shaft 601 and the module 1 according to the present invention.

[0108] With reference to FIGS. 8 and 9, the reference numbers 15 denote the magnets fastened to the motor shaft 601. These are permanent magnets, for example of the neodymium type. In the example shown in the figures, it is possible to see a single magnet 15 inserted flush in a corresponding radial seat of the motor shaft 601, but in reality the number of magnets 15 is greater than one; for example, the magnets 15 can be two, three, four, five, six, eight, ten, etc., and are arranged circumferentially on the outer perimeter of the motor shaft 601, on the same plane, with regular or non-regular pitch, which generate a corresponding magnetic field that will be read by the sensors.

[0109] In the preferred embodiment of the actuator 600, the magnets 15 are fastened to the motor shaft 601 at a portion 601′ inserted in a through hole 602′ of the box-like enclosure 602, with the aid of a bushing. Therefore, when the actuator 600 is in operation to regulate the opening of a corresponding valve, the magnets 15 are rotated together with the motor shaft 601 facing a portion 602″ of the box-like enclosure 602, which separates the motor shaft 601 from the pocket 603 where the module 1 is housed, sealingly insulated.

[0110] As can be seen, the magnetic sensors 10 and 11, which are positioned on opposite sides with respect to the second printed circuit 3, are oriented precisely in the direction of the through hole 602′, i.e. toward the magnets 15, despite the presence of the portion 602″, the magnetic sensors 10 and 11 are able to detect the magnetic field generated by the magnets 15 and, in particular, they are able to detect its intensity, which in turn depends on the mutual distance between the magnets 15 and the magnetic sensors 10 and 11. The distance between the magnets 15 and the magnetic sensors 10 and 11 depends uniquely in turn on the angular position of the motor shaft 601, which is intended to be connected integrally to the drive shaft of a valve to be controlled.

[0111] In the example 600 shown in FIGS. 7-9, the module 1 is inserted in the pocket 603 and screwed to the box-like enclosure 602 with the screws 8: a cover 14′ is then fastened at the top to close the pocket 603 sealingly. Alternatively, as described above, the module 1 can be provided already sealed in an enclosure 14 which can be inserted by pushing, snapping or can be screwed into the pocket 603.

[0112] FIG. 10 shows another pneumatic actuator 700, in a partially sectional view, equipped with module 1. It is an actuator 700 with thrust system 74 of the rack and pinion type. The module 1 is completely contained in a pocket or compartment 703 of the box-like enclosure 702 of the actuator 700, in the proximity of the motor shaft 701 but separated therefrom by an air gap 702″ of the box-like enclosure 702. In particular, the pocket 703 is insulated both on the inside of the actuator 700, where the thrust mechanism 704 fed with compressed air is present, and on the outside, when it is closed by a cover 14′.

[0113] FIG. 11 is an enlargement of FIG. 10, in particular of the portion comprising the motor shaft 701 and the module 1 according to the present invention.

[0114] With reference to FIGS. 10 and 11, the reference numbers 15 denote the magnets fastened to the motor shaft 701. In the example shown in the figures, there are three magnets 15 which are inserted flush in corresponding radial seats of the motor shaft 701, during the manufacturing step of the actuator 700 or during the overhaul step, with the replacement of the motor shaft 701. A suitable angle is defined between the magnets 15 to allow to detect all the rotation angles comprised in the range of the actuator (typically from −5° to +95°); this condition can be extended, suitably defining the angles on which the magnets 15 have to be arranged.

[0115] The magnets 15 are fastened to the motor shaft 701 at a portion 701′ inserted in a through hole 702′ of the box-like enclosure 702, with the aid of a bushing. Therefore, when the actuator 700 is in operation to regulate the opening of a corresponding valve, the magnets 15 are rotated together with the motor shaft 701 facing the air gap 702″ of the box-like enclosure 702, which separates the motor shaft 701 from the pocket 703 where the module 1 is housed, sealingly insulated.

[0116] The operation of the module 1 is identical to the one described above in relation to the first actuator 600.

[0117] Also in the example 700, the module 1 is inserted in the pocket 703 and screwed to the box-like enclosure 702 with the screws 8: a cover 14′ is then fastened at the top to close the pocket 703 sealingly, with or without screws 14′″ and gaskets 14″. Alternatively, as described above, the module 1 can be provided already sealed in an enclosure 14 which can be inserted by pushing, snapping or can be screwed into the pocket 703, with or without screws 14′″ and gaskets 14″.

[0118] FIG. 12 is a plan and sectional, i.e. a horizontal sectional, view of the portion of the actuator 700, which has the motor shaft 701 with the magnets 15 and the module 1. The module 1 is shown on a plan view, from top, and not in section. From this figure, it can be seen how the gap 702′ delimits the compartment 703 from the motor shaft 701.

[0119] FIG. 13 is a perspective and partially exploded view of the actuator 700, in which the motor shaft 701 is shown as extracted from the box-like enclosure 702, and the module 1 is shown during the installation in the pocket 703. A gasket 14″ is also visible, which allows the lid 14′ to hermetically close the pocket 703 and contain the module 1 in a water-tight manner (in this version the seal is obtained with screws 14′″ and gaskets 14″).

[0120] FIG. 14 is a schematic view that depicts the possibility of configuring the manual valves 100, 200, 400, and the electric 500 and pneumatic 600 actuators, all equipped with module 1, in a communication network supported by a remote router 800.

[0121] As explained above, the advantages offered by the module 1 and the valves 100, 200, 400, by the adapters 300 and by the actuators 500, 600 and 700 that mount them, are different. Firstly, as it can be seen in FIGS. 1-14, the module 1 is free of wired connections with the outside, since it is electrically powered by at least one battery 4 and, therefore, it does not require outer power supplies, and it can be connected wirelessly to a network, thanks to the wireless communication interface 12, which preferably communicates via radio in accordance with protocols and market standards. The compactness of module 1 makes it easy to integrate into the enclosures of the valves and actuators. This considerably simplifies the installation and management/maintenance of the modules 1 in an industrial site comprising numerous valves: in fact, it will not be necessary to carry out the wiring, which are often expensive and require significant installation times.

[0122] Among other things, the module 1 is always insulated both from atmospheric agents and from the process fluid passing through the valve, and from the compressed air fed to the actuator. The module 1 also remains electrically insulated from the other components of the electric actuator 500.

[0123] Ultimately, the module 1 allows to interface valves and actuators with the company networks in a simple and effective way, in order to obtain remotely and without effort the readings corresponding to the open state of the valves, at regular, pre-set time intervals, so as to be able to intervene promptly, if necessary, to adjust the valves.

[0124] The compactness of module 1 allows to obtain the results just described without resulting in increases in the dimensions of the actuators, because the module 1 is contained in the dimensions of the actuator.

[0125] Having the memory 13 available, the module 1 also allows to store the readings taken and to be consulted also after some time, i.e. time after the valve has been adjusted.

[0126] With reference to FIGS. 1, 2, 12 and 13, the reference numeral 16 denotes a photodiode supported by the first printed circuit 2 and powered by the battery 4. The photodiode 16 has the function of generating an alarm signal in response to a change in the light intensity detected.

[0127] The module 1 shown in the examples, in fact, implements a double anti-tampering function.

[0128] A first function relates to tampering attempts, which provide for removing or breaking the cover 14′. In this circumstance, the photodiode 16 detects the light hitting the module 1 and generates a corresponding alarm signal which is preferably sent remotely through the communication interface 12 and/or is stored, as log file, in the memory 13. This way, tampering attempts can be detected and tracked.

[0129] Preferably in the module 1, the communication interface 12 also functions as a processing unit, because it carries out a first processing of the signals generated by the magnetic sensors 10 and 11 before being sent to the router 800. The second anti-tampering function is carried out when the communication interface 12 processes the signals generated by the magnetic sensors 10 and 11 and detects that these have been altered by outer magnetic fields. In other words, when the module 1 is immersed in magnetic fields generated from the outside, for example with an electromagnet, with the attempt to render the readings unusable or falsify them, the communication interface 12 intervenes to signal the circumstance and possibly carries out safety protocols, such as sending all log files of readings previously taken, sending an alarm signal indicating the attempted tampering detected, etc. The identification of the tampering attempt can be made, for example, by comparing the signals acquired from time to time by the magnetic sensors 10 and 11 with the signals previously acquired, stored and possibly validated by the manager of valves and actuators.

[0130] The first and second anti-tampering functions can be implemented alternatively, or together.