TRANSDUCERS

Technical field

The present invention refers to the field of interface electronic systems and, in detail, it concerns a system of modular management of transducers, particularly of electric transducers of physical quantities.

Known Art

Transducers are devices that convert a physical quantity into an electrical quantity (sensors) or else vice versa (actuators). In the meaning of the present description, with the term "transducer" it will be referred to both typologies of the above described devices.

At the moment, the use of transducers (either sensors or actuators) is carried out in one of the ways hereinafter described. Referring to figure 1 , the transducer 1 of known type is directly connected to the data processing unit 5 designed to acquire data coming from the sensor 1 itself through a star connection type.

The acquiring unit provides to power supply the transducer through an electric power supply source 4 and to receive the electrical signal 6 generated by the transducer 1 itself.

Inside the data processing unit 5, a sub-stage of digitalization and numerical treatment of signal 3 provides to convert the signal, coming from the electronic circuit conditioning the signal 2, through the data bus 5b in digital signals.

Every kind of transducer, such as for example a pressure, force or temperature transducer, generates a specific type of electrical signal that must be conditioned by a specific and respective electronic conditioning circuit of the signal 2, which is usually housed inside the data processing unit 5. In detail said electrical signal 6, generated by the transducer, can be for example a voltage, current, resistance or impedance or even capacitance signal. As schematically reported in figure 2, the transducers 1 of known type can alternately have its own electronic circuit conditioning the signal lb. Such a circuit is housed inside the transducer 1 itself, and it gives a homogeneous electrical signal 6 but that can be anyway of different kinds. In fact it is known that conventional transducers can generate signals of substantially standardized type that, if they are voltage signals, assume levels of 0÷5V, 0.5÷4.5V, 0÷12V, 0÷24V, ±5V, ±10V or, if they are current signals, assume values usually comprised in the range 0÷20mA or in the range 0÷40mA.

Because of the great range of typology of output signals, even though they are conditioned, the limit and the drawback the Applicant found is that, nowadays, is anyway necessary to have a data processing unit 5 for acquiring signals that would accept and further condition the signals of different transducers in order to render them homogeneous, for example in view of their digital processing.

Finally, the Applicant observed that in last years new transducers appear on market, which have an advanced signal conditioning that included the digitalization of the signal itself. Such a new constructive transducer typology allowed to obtain a new range of transducers that can be directly interfaced with the data acquisition system through speedy serial connections of digital or numeric type, these connections being conventionally known with the term BUS. RS232, RS485, RS422, SPI, I ² C, Ethernet, CAN, WiFi, Bluetooth are some of known BUS types.

Digital conditioning of transducer signal increased considerably the price of transducers themselves, thereby restricting them in a niche about their production and use.

To aid the transducer category with advanced signal conditioning, IEEE defined a standard named IEEE 1451 standard - Networked Smart Transducer Interface - defining how TEDS (Transducer Electronic Data Sheet) like these, relatively to this transducer category, can and should send digitally or numerically, through the connecting serial line, not only the value of transduced signal but also data of type, construction, calibration of transducer itself as they have, in their inside, a memory area assigned - together with a microcontroller - to manage cleverly data present in the data sheet inside the transducer. The standardization IEEE proposed, even though it produced excellent results concerning technology, it proved to be far off the application realities, imposing high difficulties in implementation of the final solution; as a matter of fact, nowadays, diffusion of such a standard is extremely limited.

Therefore, with the present invention the Applicant had the object of producing a system for the modular management of transducers that allows to manage, simply and cleverly, families of heterogeneous transducers, in which transducers of the new generation and conventional simple transducers can coexist.

Summary of the invention

According to the present invention it is realized a system for the modular management of transducers, said system comprising at least one interface module adapted to be connected to other interface modules on a communication network; said interface module comprising:

- connecting means for the transmission of data from and towards said communication network;

- data transceiving means, said data transceiving means being adapted to be connected to at least one transducer;

- a microcontroller, electrically connected to said connecting means over said communication network and to said data transceiving means and a memory adapted to store data associated with said at least one transducer electrically connected to said interface module;

said microcontroller being arranged to allow the transmission, over said communication network, of measure data received and/or transmitted from said at least one transducer through a standard of data transmission over said communication network adapting the kind of data received and/or transmitted from said at least one transducer to said interface module.

Advantageously, said memory is readable and writable by an external electronic device through said communication network. Advantageously, said interface module further comprises at least one power supply terminal adapted to transmit electric power supply to said at least one transducer; said interface module further comprising a power stage for said at least one transducer, electrically connected to said power terminal and being arranged to protect said transducer and said interface module against electrical noises, overvoltages and/or overcurrents (over- absorptions) which can originate from the transducer itself.

In detail, said interface module comprises electric power supply means arranged to allow the power supply of at least said microcontroller and said at least one transducer that is connected to said interface module and to protect also the electric power supply line from possible malfunctions originating in an interface module present in the network.

Advantageously, said connecting means over said communication network and said electric power supply means are arranged to allow the cascade connection of said interface module to other interface modules, causing said interface module to become transparent for the other interface modules.

Advantageously, said interface module comprises temperature sensor means electrically connected to said microcontroller and wherein said microcontroller is arranged to make an automatic correction of values measured by said at least one transducer in accordance with a temperature measured by said temperature sensor means and with temperature drift data of said at least one transducer that have been previously stored in said memory; said microcontroller transmitting said automatically-corrected measured values over said communication network.

Particularly, said memory comprises data of maintenance time and/or working hours for/of said at least one transducer electrically connected to the respective interface module, and wherein said microcontroller is arranged to automatically transmit an expiration notice of maintenance time, based on said maintenance time data, over said communication network.

Advantageously, said system comprises an electric power network for said interface modules. Advantageously, said electric power network and said communication network can be combined in a single cable.

Advantageously, the communication network makes a single data bus interchanging data with other interface modules.

Advantageously, said memory is arranged to store a list of login events, or logs, to said interface module and/or said transducer.

Advantageously, said interface module is arranged to transmit alarm signals relative to said transducer over said communication network.

Advantageously, said interface module comprises means of diagnostic analysis and protection of said system from malfunctioning.

According to the present invention it is further described a method for the modular management of transducers, said method comprising:

- a step of electrically connecting at least one transducer to an interface module of a system for the modular management of transducers;

- a step of storing working data of said at least one transducer in a memory of said interface module; and

- a step of processing measure values transceived to/from said at least one transducer to said interface module by means of a microcontroller of said interface module;

said microcontroller adapting said measure values transceived to/from said at least one transducer to a transmission standard predetermined before their transmission over a communication network adapted to transmit data coming from different kind of transducers.

Said method further comprises a step of storing correction data of temperature drift of said at least one transducer in said memory and further comprising a step of processing said measure values transmitted by said at least one transducer to said interface module by means of said microcontroller; said microcontroller generating measure data corrected in accordance with said temperature drift read by said memory and in accordance with a temperature value measured by a temperature sensor of said interface module. Advantageously, it is also present a previous step of programming said at least one interface module by means of a computer, wherein said previous programming step comprises a step of selecting a communication protocol over said communication network.

Advantageously, said working data comprise maintenance time data of said at least one transducer, said method comprising a step of checking automatically if said maintenance time elapsed and said alarm signal has been transmitted to an electronic device of a supervisor or user at the moment when said maintenance time elapsed.

Advantageously, said method comprises a step of storing, in said memory, malfunction events of said at least one transducer and working time data of said at least one transducer and/or said interface module.

Advantageously, said method comprises a step of requiring the transmission of said working time data of said at least one transducer and/or said interface module, wherein said transmission requiring step is carried out through an external computer and it is sent to every interface modules connected on said communication network; said interface modules replying to said request by transmitting independent working time data.

In detail, it is further present a step of combining said communication network with an electric power network in a single cable, wherein said electric power network is arranged to allow the power supply of said interface modules and transducers electrically connected thereto.

Said method comprises a step of cascade connecting a plurality of interface modules adapted to become transparent to the remaining interface modules on said communication network, allowing said measure data received/ transmitted from/to said at least one transducer to be transferred towards interface modules placed upstream or downstream the reference interface module.

Advantageously, said method further comprises the step of transmitting at least part of data sent from said at least one transducer towards said interface module; said step of transmitting at least part of said data over said network through said adaptation to said predetermined standard, carrying out according to a predetermined criterion of temporal kind and/or of check the possibility of data transit over said communication network.

Description of the enclosed figures

During the present description, the Applicant will illustrate a non-limitative preferred embodiment of the present invention referring to enclosed figures in which:

- figure 1 illustrates a diagram of a first transducer typology of known type;

- figure 2 illustrates a diagram of a second transducer typology of known type;

- figure 3 illustrates a block diagram of an interface module being part of the system for the modular management of transducers according to the present invention; and

- figure 4 and figure 5 illustrate, respectively, a first and a second arrangement of a system for the modular management of transducers according to the present invention.

Detailed description of the invention.

Referring to enclosed figures 3 and 4, with reference numeral 100 an interface module of a system for the modular management of transducers is indicated on the whole. Said system comprises, as a matter of fact, an interface module in its turn comprising:

- at least one input of data communication network 101 ;

- at least one output of data communication network 102;

- a power supply input terminal 103 ;

- a power supply output terminal 104;

- a plurality of terminals 120, 121 , respectively for transceiving data towards a transducer 200 and its electric power supply.

On the input and output of the data communication network 101, 102, data received from transducers 200 pass as electronically processed, as it will be later described in detail, as well as data intended for the management and/or control of the interface module 100. In detail, under the present description, with the term transducer 200 it is intended every sensor or actuator device able to carry out a conversion from a physical quantity to an electrical quantity (or vice versa for the actuator); in detail, the transducer is not compatible with the IEEE 1452 standard. In other terms, it has not any microcontroller or data processing circuits towards a serial bus.

In detail, the interface module 100 object of the present invention further comprises a microcontroller 1 10 assigned for the control of data received/transmitted from/to said transducer 200, electrically connected to inputs and outputs of data communication network 101, 102 and to terminals 120, 121, respectively for the data transceiving and the electric power supply towards said transducer 200, and to input and output terminals 103, 104 of electric power supply. Particularly, the microcontroller 1 10 is electrically connected to said inputs and outputs of data communication network 101 , 102 through a data bus 1 10b, which is shown in figure 3 by a thick arrow for clarity purposes, as every lines of data interchange are; on the contrary, the lines of electric power supply are represented by a thin line.

Also data transceiving terminals 120, 121 for the power supply towards the transducer 200 are electrically connected to said microcontroller; as well as a line current measurement stage 105, electrically connected between said power supply input terminal.

Inside said microcontroller 1 10 there are also present:

- a galvanic insulator stage 106, electrically connected to said at least one input of data communication network 101 and said at least one output of data communication network 102,

- an interface stage of analog/digital input/output 107, which is electrically connected to the output terminals 120 of data transceiving with the transducer 200, and which advantageously allows to directly connect both transducers analogically operating and transducers digitally operating; - a power stage 108 for said transducer 200, the stage being connected to the power supply terminals 121 and being preferably protected against overvoltages, overcurrents and short-circuits;

- in internal clock 109, for example allowing to synchronize data received from the transducer 200 in addition to synchronize the operation of internal components with the interface module 100, first of all the microcontroller 1 10;

- a memory 11 1 adapted to store functional data in its inside, at least temporarily, concerning the transducer 200 connected to the interface module;

- a thermometric sensor 1 12 adapted to detect variations thereof and then to cause a correction of data received from the transducer 200 just in accordance with said temperature measure (correction of thermal drift).

Advantageously, the galvanic insulator is protected so that power supply noises in data transmission could damage neither the electronics of the microcontroller 1 10, when they come from the communication network connected to the input and output terminals of data communication network 101, 102, nor other electric devices, by interrupting possible overvoltages when they would come from the transducer 200 connected to the interface module 100, or else if they would come from external problems. In detail, the galvanic insulator 106, together with the protected power supply module 108, realize means of diagnostic analysis and protection of the system able to transmit malfunction alarm signals and to advantageously protect the system operation.

In use, every interface module 100 is connected to a communication network 400 such as, for example and not limitative, a LAN type network , and can also receive electric power supply through the power supply input terminal 103 and transfer it towards other interface modules 100 by the power supply output terminal 104 from a power supply network 401. For representation convenience, in figures 4 and 5 the communication network 400 is represented by a plurality of arrows with double heads and solid line. Therefore, said communication network 400 makes a data communication bus that, as briefly mentioned before, could have a data interchange protocol of 10/100/1000 Mbps Ethernet 802.3 type, or it can be defined in accordance with 1 18982, 2.0 ISO standards, part A&B, which define the CAN communication of the RS485 type. Such examples of protocol and support of data interchange must not be considered as limitative and, in case, technical equivalents could be substitutive therefor.

Such a configuration is schematically represented in figure 4, wherein a cascade configuration of a plurality of interface modules 100 is represented, each of which is electrically connected to a couple of transducers 200 that are managed independently.

The last interface module 100 is electrically connected, through its power supply input terminals 103 and input or output terminals of data communication network 101, 102, with an acquiring and controlling unit 300, in its turn electrically supplied by a battery 310. Actually, the controlling unit can be, e.g., a personal computer connected to the communication network 400 via a conventional network cable, and it is assigned to receive/transmit all data transmitted/received from the various transducers 200, which will be therefore transmitted over the network independently. Therefore, the system object of the present invention makes a tool for the contemporaneous management of data coming from a plurality of transducers of heterogeneous types and able to measure physical quantities equally heterogeneous. In detail, every interface module can be therefore configured to be able to transmit data received from the at least one transducer 200 connected therewith spontaneously, that is according to a predetermined data transmission procedure timed in accordance with a time interval that can be previously defined fixedly or adaptably based on the occupation of the bus 1 10b due to data transmissions made by other interface modules connected over the communication network 400.

In detail, in figure 4 it is illustrated a solution in which a personal computer 500 is connected to the left interface module 100. In detail, such a personal computer is connected to interface modules through the communication network 400 and a computer program is running therein, such a program being memorized on a storage medium internal or external to the computer itself and allowing the configuration of different operating parameters of every interface module 100. In figure 5 it is illustrated a variation of the connection among the various interface modules 100 inside the system object of the present invention, in which every module, although connected in a cascade network as in case of figure 4, is not power supplied by a controlling unit 300 integrating the management of the communication network 400 and of the power supply network 401, but it is supervised by a personal computer 500 electrically connected to the communication network 400 and is power supplied through the power supply network 401 by a battery 310 that is then independent from the personal computer itself. For representation convenience, the power supply network 401 is reproduced by a plurality of lines, which are connected among the various interface modules 100 this time being represented as dotted lines, so that to be evidently distinct from the communication network 400.

For reasons of convenience and integration of cables, the communication network 400 and the power supply network 401 can be combined in a single cable, the latter being provided with such suitable electric insulation means to prevent as much as possible or anyway minimize the stray coupling phenomena between the two networks.

Through the personal computer or the controlling unit 300, standard communication data could be advantageously written inside the memory 1 1 1 of every interface module 100, i.e. such a data plurality helpful to be able to correctly transmit/ receive data received from transducers over the communication network 400. For example, in a not-limitative list said standard communication data can include the baud rate, ID Message, transmission frequency, type of control, as well as alarm data in case system malfunctions or threshold exceeding would happen.

Again, inside the memory 111 also working hours of every transducers 200 connected to the respective interface module can be stored, this advantageously allowing to have an overall picture of the length of service of transducers transmitting over the communication network 400 in a centralized way, as all data can be acquired through the personal computer or the controlling unit in a single step. In addition, also dates and login events could be stored for querying said transducers 200 or the interface module itself. It will be possible to take account of data of transducer length of service also in the measures the transducer transmitted, inasmuch its length of service can positively or negatively affect them depending on cases. Every interface module 100 stores the working hours of the transducer in a completely independent way. Optionally, also working hours of the interface module itself could be stored, so that to take account of the length of service of the module for preventively calculating, for example, the replacement or overhaul time before the failure provided according to MTBF data of every single interface module.

If such data are available, also a maintenance time of transducer 200 and of the module itself could be stored inside the memory 1 1 1 : inasmuch there are some transducer types needing operations of cleaning, overhaul, maintenance or new calibration at predetermined time interval, storing these maintenance data in the memory 11 1 allows the transmission of alarm maintenance signals directly to the personal computer or the controlling unit 300 when the predetermined working threshold is reached before the maintenance. Particularly, when the communication network 400 is associated with a great plurality of interface modules, and then with a great plurality of transducers, the advantage of having an automatic signaling is important because the personnel supervising the system working, in which different transducers are operating, will not have to retain various deadlines that are many and, in addition, can be different in terms of time interval because of the heterogeneous nature of used transducers 200. This becomes a greater security in management of machineries of systems using transducers of different kind, and an important saving of time, also only for the training of the operative personnel.

The use of the inner clock 109 advantageously allows every interface module to operate both on communication networks of synchronous or asynchronous type, simply by programming the microcontroller 1 10 conveniently.

This makes strongly flexible every module object of the system, even if not forced to transceive data over a communication network of predefined type; then every interface module can be drawn out from the network in which it was operating, and can be installed on a new network or system even if using a different communication protocol, by its new setting.

Advantageously every microcontroller 110, when the interface module 100 is turned on, provides to carry out an automatic procedure for controlling the transducer 200 or transducers connected thereto. In detail, such a procedure comprises an automated sending of data received from transducers 200 or to personal computer or controlling unit 300 connected on the communication network 400.

Still when said at least one interface module 100 is turned on, by means of the personal computer or controlling unit it will be possible to carry out a previous step of defining and programming the communication protocol that the different interface modules will have to use in order to transmit data measured by transducers on the communication network 400.

The memory 1 1 1 holds, in its inside, also data inhering the total number of working hours of the respective interface module 100, as well as a list of notable alert data adapted to cause or to be cause of malfunction: such a list includes, not limitatively, high temperature, high current absorption, low supply voltage, alarm conditions and it will be unloaded into the personal computer and the controlling unit over the communication network 400.

The measurement stage of line current 105 that is schematically reported, for sake of simplicity representation, in enclosed figures with a box containing an amperometric meter, is arranged for revealing possible short-circuits present on the power supply network 401 and when they happen, for transmitting a certain short-circuit alarm to the microcontroller 1 10 that will provide to active a function for the disconnection from the power supply network 401.

The interface module 100 is adapted to transmit measure data of physical quantities over the communication network 400 which are automatically corrected in accordance with at least the variations of local temperature. As a matter of fact, different data relative to transducers 200 can be stored in the memory 1 1 1 of every interface module 100, the transducers being connected to the module. Particularly, the memory 1 1 1 is arranged for containing:

- plate data of transducer 200, and then the manufacturer, type, model, serial number, calibration, interface type; these data are usually available on data sheet of every sensor and can be stored by using the personal computer or controlling unit;

- data of temperature compensation, if present and necessary, i.e. those data reporting how the transducer 200 varies its measurement because of temperature influence

- transducer application data, i.e. those data reporting the behavior of the transducer itself during the specific application (for example: mnemonic transducer, its current absorption, the accepted power supply tolerance, the reference voltage, ...)

As a matter of fact, when a physical quantity is measured through the transducer, before the data could be transmitted over the communication network 400, the microcontroller 110 will carry out an automatic correction of the measured value according to the temperature detected by the temperature sensor 1 12 and to the temperature drift value stored in memory 1 11 , by increasing or decreasing automatically the measure of the transducer 200 before it is sent over the network. Therefore, advantageously by the system object of the present invention, data received from the controlling unit 300 or the personal computer 500 will be anymore affected by the working temperature, and therefore they will not need a post-processing, sometimes manually but anyway difficult (since it is necessary to subsequently remember the temperature values at which the transducers operated at the measure moment) and time wasteful.

All previously stored data that are adapted to be stored inside the memory 11 1 , as well as the configuration of the interface module or interface modules in the system object of the present invention, can be advantageously carried out by a computer program run by the personal computer, and configured to allow specifically the dialog with the various interface modules 100. Advantageously this allows not to use a personal computer specifically configured to be used with the system of the present invention, thereby allowing the simple installation of a program available along with the system, virtually on every type of personal computer. In this way it has to be noticed that, even if in the present invention it has been referred to a personal computer, such an indication must not be considered as limitative, inasmuch it will be equally replaced by every electronic device provided with a data processing capability that even modern smartphones, tablet PCs or still proprietary electronic devices can have.

Lastly, it has to be noticed that the input and output of the data communication network 101 , 102 are such to render the interface module "transparent" to other interface modules connected over the data communication network 400, so that it is not necessary to configure again the module itself when a new module is added. Input and output 103, 104 of the electric power supply operate in the same way, substantially rendering every interface module as a bypass absorbing the amount of electric power necessary to its operation and to that of remaining interface modules 100, thereby allowing the electrical power transfer. Therefore, every interface module 100 does not impede the transferring of data measured by transducers of other interface modules both towards modules connected upstream it and towards those connected downstream, thereby assuring a bidirectional flow of data transceiving with respect to its position in the communication network 400.

From the above description, advantages of the system object of the present invention are clear. It allows to manage a plurality of transducers of different kind in an intelligent and centralized way, by receiving data and being able to control and compensate measures of heterogeneous transducers measuring, in their turn, physical quantities as much heterogeneous in a simple and practical way. Therefore, the communication network will use the same communication standard of measure data independently from the kind of various transducers, and such a standard will be managed by the microcontroller through a transmission adaptation variable for each transducer in a predetermined way. From the user point of view, the use of the system object of the present invention allows not to have to replace outdated sensors or, anyway, it allows to adapt the plurality of used sensors on a single family or kind. Furthermore, the system object of the present invention can be

"moved" simply from a machinery to another, i.e. by disconnecting the interface modules from respective transducers for their connection with others of different kind, if needed, with the only carefulness of reprogramming the system for the operation with the new sensors.

Nevertheless, the system object of the present invention could be used as well to carry out tests - for example of pre-production or pre-sale - on a wide plurality of sensors.

Lastly, it is evident that variations, additions and modifications obvious for a person skilled of the art can be applied to the system object of the present invention, without thereby departing from the protection scope provided by the enclosed claims.