Patent Application
20200056783
The present invention concerns a valvular control circuit associable with an apparatus powered by gas, such as for example natural gas, methane, propane or other gases, or mixtures of air and gas.
By way of non-restrictive example, the apparatuses in question comprise boilers, storage water-heaters, stoves, furnaces, fireplaces or other similar or comparable apparatuses.
Valvular control circuits are known, able to control and regulate gas-powered apparatuses in which there are one or more safety and/or regulation valves that, depending on the regulation set on each occasion by the user, power the main burner of the apparatus.
Some valvular control circuits have a thermoelectric power source that, cooperating with an auxiliary heat source, generally called pilot light, makes the valvular control circuits self-powered.
During start-up, the pilot light is generated by a manual drive that is maintained functioning by the user until the thermoelectric power source generates a stable electric power voltage sufficient to power both the control electronics and also the safety and/or regulation valves.
The thermoelectric power source typically generates a limited electric voltage that has to be amplified in order to power the control electronics and at the same time to supply the necessary power to drive the safety and/or regulation valves.
In this context, due to the slow time constant of the thermoelectric power source and the drops in voltage at the heads of the safety and/or regulation valves, during start-up the user has to keep the manual drive activated for rather a long time.
If the apparatus is a storage water-heater, it is fundamental to guarantee a continuous functioning and, in this context, the element most at risk is the thermoelectric power source.
Indeed, since it is heated to temperatures in the range of 600° C.-750° C., the thermoelectric power source is very sensitive to oxidation, which leads to progressive wear and eventually breakage.
The variability of the pilot light caused for example by drafts, composition and pressure of the power gases, drops of condensation etc., makes it difficult to assess the state of wear of the thermoelectric power source.
This assessment is made even more complicated since, as the thermoelectric power source approaches breakage point, it is subjected to a deterioration that is not distinguishable from the variations due to its normal functioning.
Furthermore, from a safety point of view, it is necessary that the valvular control circuits cannot be tampered with by a user, or if this happens, the tampering must be detected so that the apparatus can be promptly blocked, so as to prevent accidents that can even be very serious.
There is therefore a need to perfect and make available a valvular control circuit that overcomes at least one of the disadvantages of the state of the art.
The purpose of the present invention is to provide a valvular control circuit associated with a gas-powered apparatus that allows to power quickly both the control electronics and also the safety and/or regulation valves at every start-up, or following temporary malfunctions.
Another purpose is to provide a valvular control circuit that also allows to program the maintenance operations and/or replacements of parts of the valvular control circuit and/or the apparatus associated therewith.
Another purpose of the present invention is to provide a valvular control circuit able to monitor the power condition thereof, and that at the same time allows to promptly verify whether any dangerous tampering has occurred.
The Applicant has devised, tested and embodied the present invention to overcome the shortcomings of the state of the art and to obtain these and other purposes and advantages.
The present invention is set forth and characterized in the independent claim, while the dependent claims describe other characteristics of the invention or variants to the main inventive idea.
In accordance with the above purposes, embodiments of the present invention concern a valvular control circuit comprising a first valve element coupled with a first valve switch, a second valve element coupled with a second valve switch, a control and command unit coupled with a DC/DC electric voltage converter and able to command the first valve switch and the second valve switch by means of a command signal, said first valve element being coupled to a manual drive member to generate a pilot light.
According to possible embodiments, the present invention concerns a valvular control circuit comprising a first valve element coupled with a manual drive member to generate a pilot light, a second valve element coupled with a second valve switch, and a control and command unit coupled with a DC/DC electric voltage converter and able to command the second valve switch by means of a command signal.
In accordance with one aspect of the present invention, the valvular control circuit comprises a first thermoelectric power source coupled with the DC/DC electric voltage converter, and a second thermoelectric power source coupled with at least one of either the first valve element or the second valve element, the thermoelectric power sources both being fed by the pilot light.
According to possible embodiments, the first thermoelectric power source is coupled with the DC/DC electric voltage converter and the second valve element, and the second thermoelectric power source is coupled with the first valve element.
According to possible embodiments, the second thermoelectric power source is coupled with the first valve element and with the second valve element.
According to a variant, the second thermoelectric power source comprises a thermocouple.
According to a variant, the pilot light affects both the thermoelectric power sources to an equal extent, said thermoelectric power sources being disposed at a substantially equal distance from the pilot light.
According to a possible variant, the first and the second thermoelectric power sources are disposed in a single protective container so as to be subjected to the same heating conditions.
According to a possible variant, the valvular control circuit comprises a rechargeable energy source removably coupled with the DC/DC electric voltage converter and with the control and command unit.
According to a variant, at least one of either the first or second thermoelectric power sources comprises a thermopile.
According to a variant, the first and second thermoelectric power sources are identical to each other.
According to a variant, the first and second thermoelectric power sources have, with respect to each other, one or more different characteristics chosen from the time constant, electric resistance and electromotive force which can be generated.
According to a possible variant, the control and command unit has at least a monitoring device able to monitor the electromotive force generated by one or both of the thermoelectric power sources and to signal their functioning state and/or wear in relation to the electromotive forces measured.
The control and command unit has, or is connected to, a sensor able to detect the electric voltage of one or both of the thermoelectric power sources and, if the electric power voltage detected is greater than a threshold value of electric voltage, or the difference of electric voltage between the thermoelectric power sources is comprised in a predetermined voltage range, said sensor is configured to send an alarm signal.
These and other characteristics of the present invention will become apparent from the following description of some embodiments, given as a non-restrictive example with reference to the attached drawings wherein:
To facilitate comprehension, the same reference numbers have been used, where possible, to identify identical common elements in the drawings. It is understood that elements and characteristics of one embodiment can conveniently be incorporated into other embodiments without further clarifications.
Embodiments described here with reference to the drawings concern a valvular control circuit 10 configured to control the functioning of a gas-powered user apparatus.
The gas-powered user apparatuses in question comprise boilers, storage water-heaters, stoves, furnaces, fireplaces or other similar or comparable apparatuses in which there is a main burner 11 powered by natural gas, methane, propane or other gases, or mixtures of air/gas.
For example, if the gas-powered apparatus is a storage water-heater, the main burner 11 is configured to heat the load 31, that is, the water, to a desired temperature.
According to possible embodiments, the valvular control circuit 10 comprises a first valve 12 and a second valve 14 coupled with a second valve switch 15.
According to possible embodiments, the first valve 12 can be coupled with a first valve switch 13.
It is understood that the word “valve” here means any valve element, driven mechanically, electromechanically or electrically, comprising one or more valves associated with each other to form a functional component.
The first valve 12 and the second valve 14 can each comprise, for example, an electrovalve that switches its state from closed to open and vice versa, when an electric command signal is sent respectively to the first valve switch 13 or the second valve switch 15.
During the start-up step, the first valve 12 is opened manually and this operation can be performed by driving a manual drive member 20.
During the switching off step, the first valve 12 can be closed electronically, if it is associated with the first valve switch 13, or manually in the absence of the first valve switch 13.
The first valve 12 functions as an entrance safety valve which, when it is open, allows the gas to transit from the gas feed source to the user apparatus.
The second valve 14 functions as a valve to regulate the feed gas to the main burner 11.
The second valve 14 can function as a supplementary safety valve. When the second valve 14 is closed, the first valve 12 can feed only the pilot light 21 through the pilot path.
The first valve 12 and/or the second valve 14 can each be coupled with a pressure regulator to define on each occasion the delivery pressure of the gas exiting from the corresponding valve.
The valvular control circuit 10 comprises a command and control unit 16 coupled with a DC/DC electric voltage converter 17.
The command and control unit 16 is able to command the first valve switch 13 and/or the second valve switch 15 by means of a command signal sent to them.
According to possible embodiments, the DC/DC electric voltage converter 17 coupled with the command and control unit 16 is able to convert an entering DC electric voltage into an amplified DC electric voltage at exit, so as to power the command and control unit 16 with the necessary voltage.
According to possible embodiments, when necessary, the command and control unit 16 sends a command signal to the first valve switch 13 and/or the second valve switch 15 to switch the state of the corresponding valve 12 and/or 14.
The command and control unit 16 can comprise a programmable microprocessor, an electronic circuit, an electronic board or other similar or comparable electronic unit.
The command and control unit 16 can comprise, or be connected to, a selection unit 18 configured to select the temperature to which the load 31 is to be taken, for example water if the user apparatus is a storage water-heater.
For example, the selection unit 18 can comprise a thermostat provided with knobs and/or a user interface by means of which the user can select the temperature.
The command and control unit 16 can comprise, or be connected to, one or more temperature probes 19 located in the area where the temperature is to be regulated. For example, the temperature probe 19 can be immersed inside the liquid to be heated.
The cooperation between the selection unit 18 and the temperature probe 19 allows to continuously monitor and regulate the temperature of the load 31 according to the desired temperature.
According to possible embodiments, the first valve 12 is coupled with a manual drive member 20 to generate a pilot light 21.
In particular, at least during the first ignition or restarting step, the manual drive member 20 is configured to open the first valve 12 to allow the gas to transit along the pilot path and feed the pilot light 21.
This can be carried out with the aid of a piezoelectric device, or other similar device.
The start-up or restart step is obtained while keeping the second valve 14 closed, so as not to feed the main burner 11 during the start-up step.
The manual drive member 20 can be included in the selection unit 18, or can be connected to it, or can be independent from it.
If the manual drive member 20 is separate from the selection unit 18, the preselection of the temperature remains unchanged when the valvular control circuit 10 is switched on, off or on stand-by.
According to one aspect of the present invention, the valvular control circuit 10 comprises a first thermoelectric power source 22 coupled with the DC/DC electric voltage converter 17, and a second thermoelectric power source 23 coupled with at least one of either the first valve element 12 or the second valve element 14, said thermoelectric power sources 22, 23 both being fed by the pilot light 21.
According to possible embodiments, the first thermoelectric power source 22 is coupled with the DC/DC electric voltage converter 17 and the second valve 14, and the second thermoelectric power source 23 is coupled with the first valve 12.
According to a variant, the second thermoelectric power source 23 comprises a thermocouple 26.
The thermocouple 26 has very quick reaction times that can further reduce the time for which a user has to keep the manual drive member 20 in action.
This high reactivity of the thermocouple 26 also allows to detect promptly any possible variations in the pilot light 21, and hence to intervene immediately.
One of the advantages that can be obtained according to the present invention concerns the possibility of effectively assessing the state of wear of each of the thermoelectric power sources 22 and 23.
By constantly monitoring both the thermoelectric power sources 22 and 23, it is possible to assess the evolution over time of the parameters that characterize them.
In particular, from one or more differences in the temporal evolution, for example of the electric resistances, the electric voltages at their heads, or the electric voltage on a load located between the two thermoelectric power sources 22 and 23, it is possible to determine the functioning state and/or the state of wear of one or both the thermoelectric power sources 22 and 23.
This combined monitoring of both thermoelectric power sources 22 and 23 allows to foresee, in time, when and which source will need to be replaced.
In fact, it is possible to define on each occasion, also with self-learning algorithms, a series of reference events in the evolution of the parameters monitored, with which specific states of the thermoelectric power sources 22 and 23 are associated.
This not only allows to program the maintenance operations but also to monitor in detail the functioning of the valvular control circuit 10 and of the user apparatus associated with it.
According to a variant, the pilot light 21 affects equally both the thermoelectric power sources 22 and 23, since said thermoelectric power sources 22 and 23 are disposed at a substantially equal distance from the pilot light 21.
According to a possible variant, the thermoelectric power sources 22 and 23 are disposed in a single protective container 24, so as to be subjected to the same heating conditions.
The protective container 24 also allows to protect the two thermoelectric power sources 22 and 23 against external agents that can change their functioning.
According to a variant, the thermoelectric power sources 22 and 23 are identical.
The combination of one or more of the aspects described above obtains more advantageous solutions, since the working conditions of the two thermoelectric power sources 22 and 23 are always closer to each other.
According to a variant, the thermoelectric power sources 22 and 23 can have one or more reciprocally different characteristic parameters, chosen from a group comprising time constant, electric resistance and electromotive force that can be generated.
According to a possible variant, the command and control unit 16 has or is connected to at least a monitoring device 25 able to monitor the electromotive force generated by one or both the thermoelectric power sources 22, 23 and to signal to a user their state in relation to the electromotive forces measured by the monitoring device 25, for example by means of a user interface or signaling LEDs or other signaling mean.
The monitoring device 25 can be integrated in the command and control unit 16, or can be connected to it.
The measurement of the electromotive forces generated can be carried out by measuring devices connected to the heads of the thermoelectric power sources 22 and 23.
Using two thermoelectric power sources 22 and 23 allows to obtain reliable information in rapid time, since the differential analysis of the trend of the electromotive forces is more precise than an analysis of the absolute values referred to a single thermoelectric power source.
In fact, monitoring only the absolute values referred to a single thermoelectric power source, the latter would be confused with the characteristic fluctuations of the system.
For example, when the second valve 14 is opened, the ignition of the main burner 11 causes a corresponding temporary variation in the trend of the electromotive force generated by the two thermoelectric power sources 22 and 23.
By suitably monitoring and combining the characteristics of the two thermoelectric power sources 22 and 23, the command and control unit 16, and in particular the monitoring device 25, is able to quickly determine whether the pilot light 21 and/or the main burner 11 have been ignited successfully.
Another advantage of having two separate and distinct thermoelectric power sources 22 and 23 is that this also makes the feed to the command and control unit 16 separate from the feed of one or both the valves 12 and 14.
This considerably reduces the start-up times compared with feeding from a single thermoelectric power source, since the load fed is divided between the two thermoelectric power sources 22 and 23.
This has the advantage that it does not require the user to prolong the action on the manual drive member 20.
In fact, especially during the start-up step, if there is only one thermoelectric power source, it is subjected to a very high load because the command and control unit 16 is also present, which is also designated to control the functioning of the valvular control circuit 10.
Considering that the power voltage can diminish suddenly to very low values, for example due to drops of condensation falling onto the thermoelectric power sources 22 and 23 and/or onto the pilot light 21, the operating continuity of the valvular control circuit 10 must be guaranteed.
With reference to
In the event of a drop in voltage, with reference to
In these embodiments, when the first valve switch 13 intervenes, the first valve 12 is closed and consequently also the pilot path that feeds the pilot light 21.
This causes the valvular control circuit 10 to switch off and requires manual rearming in order to start functioning again.
With reference to
This solution solves the problem caused by the drops in voltage because the first valve 12 is not switched in response to the interruption in the power of the command and control unit 16, and stays open even for very low power voltages, at which the command and control unit 16 would not be able to function.
In other words, following a sudden drop in the power voltage, the command and control unit 16 and also possibly the main burner 11 can switch off, while the pilot light 21 stays ignited, since the first valve 12 does not change its state.
This has the advantage that, if the command and control unit 16 stops functioning, even temporarily, the valvular control circuit 10 self-restores thanks to the action of the pilot light 21, which is not affected by the interruption in the power.
In this solution too, a monitoring device 25 can be provided, able to compare the feed of the thermocouple 26 and the thermopile 27 to establish their degree of wear.
In this way, all the safety functions are mechanical, while the command and control unit 16 is designated to perform a thermostat function, and to control and possibly signal the state of the two thermoelectric power sources 22 and 23.
According to a variant, at least one of the thermoelectric power sources 22 and 23 comprises a thermopile 27.
According to a possible variant, the valvular control circuit 10 can comprise a rechargeable energy source 28 removably coupled with the DC/DC electric voltage converter 17 and the command and control unit 16.
The rechargeable energy source 28 allows to activate the command and control unit 16 in advance, before the time needed to activate the first thermoelectric power source 22.
This allows the command and control unit 16 to signal quickly to the user that the pilot light 21 has been ignited.
In fact, without this strategy, the user has to keep the manual drive member 20 active for a time longer than that generally necessary, because the user cannot know if the pilot light 21 is actually ignited and stable.
The fact that the pilot light 21 has been ignited can be signaled by means of signaling LEDs or other signaling means comprised in or connected to the command and control unit 16.
For example, the rechargeable energy source 28 can comprise a rechargeable battery, which can be connected, when necessary, to power the command and control unit 16.
The connection can be made automatically during the ignition of the pilot light 21, or it can be selective and set on each occasion by a user.
For example, the connection can be obtained by driving the manual drive member 20, which in turn acts on a switch 32 put in series with the rechargeable energy source 28.
It is quite clear that the valvular control circuit 10 can also function without the rechargeable energy source 28, since the latter can be disconnected or removed and the power supplied directly by the first thermoelectric power source 22.
If one of the thermoelectric power sources 22 and 23 is a thermopile 27, it is possible to use the excess energy possibly available at its heads to recharge the rechargeable energy source 28.
According to possible embodiments, the command and control unit 16 can have, or be connected to, a sensor 29 able to detect the electric voltage of one or both of the thermoelectric power sources 22 and 23 and, if it is greater than a threshold value of electric voltage, the sensor 29 is configured to send an alarm signal 30.
The presence of the sensor 29 increases the overall safety level of the valvular control circuit 10 and of the user apparatus connected to it, since it allows to detect promptly whether a user connects an external power source, such as for example a battery, to the valves 12 and 14 and/or to the command and control unit 16.
In fact, without the pilot light 21, the valves 12 and 14 must stay closed, to prevent the leakage of unburnt gases.
An external power source could cause the valves 12 and 14 to open even without the pilot light 21, with consequences for the user's safety.
Following the detection that the threshold conditions have been exceeded, the command and control unit 16 is configured to close the valves 12 and 14 and block the functioning of the user apparatus.
The sensor 29 is also configured to measure the difference in the electric voltage between the heads of the two thermoelectric power sources 22 and 23 and, if it is comprised within a predetermined voltage range, the sensor 29 is configured to send an alarm signal 30.
It is clear that modifications and/or additions of parts may be made to the valvular control circuit 10 as described heretofore, without departing from the field and scope of the present invention.
It is also clear that, although the present invention has been described with reference to some specific examples, a person of skill in the art shall certainly be able to achieve many other equivalent forms of valvular control circuit 10, having the characteristics as set forth in the claims and hence all coming within the field of protection defined thereby.
In the following claims, the sole purpose of the references in brackets is to facilitate reading: they must not be considered as restrictive factors with regard to the field of protection claimed in the specific claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2017-0052213 | Apr 2017 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2017/075379 | 10/5/2017 | WO | 00 |
