FR2816033A1 - Multi-valve for pressurised gas tank e.g. for LPG has optical level detector and filling limiter combined with controller and gauge - Google Patents

Abstract

The multi-valve (1) consists of a housing (2) connected on one side to a tank filler pipe and on the other to a feed pipe. It incorporates an optical detector (11) for the fluid level and a filling limiter (9a) combined with a controller (13) and fluid level gauge. The optical detector comprises an infrared sensor, emitter and receiver, with an amplifier connected to the controller, while the filler (9) has a solenoid valve (5) assisted by the limiter (9a) and pilot controlled by the controller.

Description

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 The technical sector of the present invention is that of safety and supply devices intended to equip tanks containing a pressurized liquid fluid such as liquefied petroleum gas (LPG) used as fuel for motor vehicles.

 In order to reduce the pollution linked to releases into the atmosphere resulting from the massive use of motor vehicles, it is desirable to develop the consumption of less polluting fuels than petrol or fuel oil.

 Gaseous fluids liquefied under pressure, such as petroleum gas or natural gas, constitute fuels which respond to the evolution of new environmental constraints.

 For example, compared to gasoline, LPG generates the emission of a quantity of carbon dioxide lower by 40 to 75% and a quantity of unburnt hydrocarbons and nitrogen oxide lower from 30 to 65%. This reduction is all the more significant when the vehicle makes short-distance journeys, since it is well known that the size of the discharges is a function of the engine temperature.

 It should also be noted that this LPG fuel has the advantage of not containing additives such as lead, sulfur or benzene, the emission of which is harmful to the health of populations.

 Liquid gaseous fluids under pressure are contained in reservoirs which withstand constraints related to their confinement under determined conditions of temperature and pressure and to the possible evolution of their physico-chemical properties which result therefrom. Indeed, LPG is in binary equilibrium between a liquid phase and a gas phase. This state can, under the effect of temperature, cause a significant rise in internal pressure which can cause the tank to explode.

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This is the reason why, in order to avoid possible deterioration of the reservoir, the filling must be limited and, to this end, arrangements are made for the liquid phase to occupy only 80% of the available volume. The 20% of volume remaining above constitutes a gaseous sky capable of absorbing the dilations of the liquid phase as a function of variations in ambient temperature. However, this limitation must take place under optimal conditions and without leakage rate, which is not the case in the current state of the art.

 Patent EP 0 884 512 describes a valve unit for a gaseous fuel tank. However, it has a number of drawbacks. in addition to not incorporating a filling limitation, there are no different devices on this unit necessary for the operation and safety of a vehicle powered by LPG.

 The object of the present invention is therefore to remedy these drawbacks by designing a polyvane integrating and combining the functions of level detection, filling limitation, fuel gauging and supply, all on a single and same support.

 The subject of the invention is therefore a polyvalve for a container intended to contain a gaseous pressurized fluid, of the LPG type, consisting of a body connected on one side to a filling duct and on the other to a duct of supply, characterized in that it comprises a means for optical detection of the level of fluid in the container and a device for limiting filling in combination with management means, filling of the container, gauging of the fluid and supply, attached to the body.

 According to a characteristic of the invention, the optical detection means consists of an infrared sensor connected to the body, comprising a transmitter, a receiver and an amplifier electrically connected to the management means.

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According to another characteristic of the invention, the filling means is constituted by a filling solenoid valve assisted by the filling limitation device, said solenoid valve being connected to the body and controlled by the management means, this structure cooperating to stop filling according to a set point.

 According to yet another characteristic of the invention, the filling limitation device comprises: - a channel connected to the container by means of a non-return valve, - a duct connected to the filling duct, - a piston for closing the channel and delimit a cavity with the filling solenoid valve, - and means for controlling said piston.

 The control means include: - a first pipe passing through the piston and connecting the cavity to the channel, the filling solenoid valve obstructing said pipe, - a second pipe connecting the cavity to the pipe.

 Advantageously, the pressure drop of the first pipe is lower than that of the second pipe, to push back the piston when the filling solenoid valve is open and allow the passage of the fluid directly from the conduit to the channel.

 Advantageously also, the supply means is constituted by a supply solenoid valve controlled by the management means to put in communication, through the body, the drawing device with the supply duct.

 According to a characteristic of the invention, the drawing-off device comprises a tube connecting a filter to a flow limiter integral with the body of the polyvalve.

 According to another characteristic of the invention, the gauging means is constituted by a device

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 float rheostat connected to the management means to deliver a level indication to the vehicle dashboard.

 According to an alternative embodiment of the invention, the management means has the possibility of stopping the filling either as a function of the optical detection means, or as a function of the gauging means.

 According to another alternative embodiment of the invention, the body of the polyvane comprises internal conduits, channels and conduits necessary for the transit of the fluid in the filling and supply means.

 Finally, the management means receives, manages and transmits the information necessary for the operation of the polyvane and integrates an autonomous energy source for electrically supplying the optical detection means, the filling means, the supply means, the gauging.

 A very first advantage of the multi-valve according to the invention lies in the fact that it combines all the functions usually used in an LPG system and, this, on a single support.

 Another advantage lies in the ability of the multi-valve to be completely autonomous with respect to the vehicle.

 Another advantage of the multi-valve according to the invention lies in the fact that it has no leakage rate.

 Other characteristics, details and advantages of the invention will emerge more clearly on reading the additional description given below for information only in relation to the drawings in which: - Figure 1 is a top view of the valve according to the invention, - Figure 2 is a partial view of the multi-valve representing the means of optical level detection in the absence of liquid fuel, - Figure 3 is a partial view of the multi-valve

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 representing the level detection means in the presence of liquid fuel, - Figure 4 is a sectional view of the polyvane showing the filling and management means, - Figure 5 is a sectional view of the polyvane according to l the invention representing the supply means, - Figures 6A-6C show a section of the flow limiter, - and Figure 7 is a sectional view of the polyvalve showing more particularly the gauging means and the management means.

 In Figure 1, there is shown a top view of the valve 1 according to the invention mainly consisting of a body 2 of generally cylindrical shape. This body 2 is pierced in its peripheral part with at least one opening 3 necessary for fixing the polyvane 1 to a container. In the illustration described in this figure, we note the presence of eight fixing holes 3 on the container which will, in this embodiment, a vehicle tank 4 shown partially. The body 2 supports two solenoid valves 5 and 6 and is provided with a filling orifice 7 and a supply orifice 8.

The filling solenoid valve 5 and the filling orifice 7 are part of the filling means 9 which will be described later in relation to FIG. 4. The supply solenoid valve 6 and the supply orifice 8 are part, as regards to them, the supply means 10 which will be described in more detail with reference to FIG. 5. An optical detection means 11 is also seen, which is also secured to the body 2, for example by screwing. This joining method has the advantage of making the optical detection means 11 adjustable in depth to adapt it to the different possible configurations of the tank. This figure also shows the positioning of a sealed crossing 12 of the body 2 necessary for the transit of a

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 gauging information between the gauging means (not shown in this figure) and the management means 13. By management means must be understood an electrical, electronic or computer device capable of receiving, managing, conditioning and transmitting all the information necessary for internal functioning of the valve as well as the signals coming from or intended for the vehicle (gauging information).

 There is shown in Figures 2 and 3 a partial sectional view of the optical detection means 11 illustrating the two detection phases, that is to say the presence (fig. 2) and the absence (fig. 3) liquid fuel. In Figure 2, there is shown the optical detection means 11 consisting of an infrared sensor 14 screwed through the body 2. This sensor 14 is composed of a receiver 18, an amplifier 23 and a transmitter 15 which sends a light beam 16 to a reflecting prism 17. The latter will return without changing the trajectory the beam 16 to the receiver 18 connected to the amplifier 23 when the prism 17 is immersed in a gaseous atmosphere. This sensor 14 is connected to the management means 13 via three conductors 20, 21, 22. The conductors 20 and 21 allow the supply of electrical energy to the sensor 14 while the conductor 22 conveys the LPG level information.

 Figure 3 shows the sensor 14 where the prism 17 is immersed in a liquid atmosphere such as LPG. The reflection of the beam 13 is then disturbed or obscured.

 The operation of this optical detection means 11 is as follows. As described above, the presence or absence of liquid will influence the reflection of the prism 17. In the case of the presence of LPG, the reflection of the beam 16 by the prism 17 is disturbed, the receiver 18 therefore does not receive plus this beam. The amplifier 23 then delivers level information via the conductor 22 to the means of

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 management 13. The form of this information, of the normally open or normally closed type, is of course harmonized with the electrical or electronic requirements of the management means 13.

 This sensor 14 is judiciously positioned so that the prism 17 is placed at a level corresponding to 80% of the total volume of the tank when the vehicle is in a position close to normal. This sensor becomes the initiator of the filling stop for the management means 13, the latter then acting on the filling solenoid valve 5 to control its closing.

 The description of the filling means 9 and of the filling limitation device 9a will follow in relation to FIG. 4 illustrating a sectional view A-A.

Note in this figure the presence of a filling conduit 24 connected upstream by any means to the filling orifice 7 of the container or tank. In the example illustrated here, it is a known type of threaded sleeve. The filling means 9 comprises the filling conduit 24, the filling solenoid valve 5, the filling orifice 7 and the filling limitation device 9a, the description of which will follow. The filling orifice 7 is connected to a conduit 25 formed in the body 2 which opens into a chamber 26 of substantially annular shape. The latter is delimited on one side by a piston 27 and on the other by the body 2. The chamber 26 has a protuberance in the form of a collar 28 and pierced at its center to form a channel 29 which opens onto a anti-backflow valve 30 or non-return valve. The latter is based on a known principle of the spring / ball or spring / piston / seal type which it is not necessary to describe in more detail. The purpose of this backflow valve 30 is to prohibit the ascent of the liquid, in this case LPG, from the tank 4 to the filling means 9.

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The piston 27 is pierced in its center by a first pipe 31 having two different diameters. This pipe opens out on one side into the channel 29 and on the other into a cavity 32. A second pipe 33, of a diameter smaller than the first connects the chamber 26 to the cavity 32. The first and second pipes 31 and 33 form the control means of the filling limitation device 9a. In this illustration, the piston 27 is of substantially cylindrical shape and has a first shoulder 34 and a second shoulder 35 on which the filling solenoid valve 5 rests and to obstruct the pipe 31.

 The operation of the filling limitation device 9a is as follows. FIG. 4 is an illustration of the polyvalve 1 in the filling prohibition phase, that is to say in the case where the optical detection means 11 detects the desired level, for example for a setpoint corresponding to 80% of the tank volume 4.

 The LPG arrives via the line 25 after having been brought in through the filling line 24 and passed through the filling orifice 7. The fuel then fills the chamber 26 and enters the cavity 32 via the line 33. The solenoid valve 5 being supported on the second shoulder 35, it therefore prohibits the passage of LPG in the pipe 31 with the consequence of creating a pressure balance on either side of the piston 27. In this configuration, the piston 27 is supported on the flange 28 by means of the shoulder 24.

 During the filling authorization phase, the management means 13 gives the order to the filling solenoid valve 5 to release the shoulder 35 and thus allow the LPG to pass from the cavity 32 to the pipe 31. The pressure drop being more important in line 33 than in line 31, a difference is created

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 pressure between the cavity 32 and the chamber 26 causing the displacement of the piston 27. This displacement then releases the flange 28 and allows a direct passage of the fuel from the conduit 25 to the channel 29. The supply pressure being greater than the pressure of calibration of the spring of the non-return valve 30, the LPG pours inside the tank.

 As soon as the reservoir has reached the setpoint level detected by the optical detection means 11, the management means 13 orders the filling solenoid valve 5 to obstruct the pipe 31 by coming to bear on the shoulder 35. The pressure balance is then created between the cavity 32 and the chamber 26, the liquid support surface being larger in the cavity 32 than in the chamber 26, the piston 27 then moves and therefore comes to obstruct the direct passage fuel by junction between the first shoulder 34 and the flange 28. This is so since the solenoid valve pushes the piston by the only action of the spring since the pressure being in equilibrium on both sides the force of closing the piston is very weak.

 The filling limitation and stop function is therefore ensured without leakage rate because no fuel circulation is possible between the filling pipe and the interior of the tank during the filling limitation phase.

 FIG. 5 is a sectional view BB of the polyvalve 1 showing the supply means 10. We see there the supply solenoid valve 6 mounted integrally on the body 2. Unlike the filling means 9, the supply means 10 distributes the fuel from the tank 4 to the engine of the vehicle via a supply duct 34 connected to the body 2 by the supply orifice 8. The latter is extended by a first channel 35 which opens into a main channel 36 both practiced in the body 2. A second channel 37

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 connects a recess 38 to the main channel 36. This recess 38 is delimited at the bottom and on the sides by the body 2 and on the top by the supply solenoid valve 6. The part of the second channel 37 projecting into the recess 38 is terminated by a seat 39. The end of the supply solenoid valve 6 is therefore applied to this seat 39 to prevent the passage of LPG.

 The LPG is drawn from the bottom of the tank and passes through a filter 40 secured to a tube 41 or drawing pipe. Opposite the filter 40, the hollow tube 41 is connected to the body 2 by means of a flow limiter 42 shown in section in FIGS. 6A, 6B and 6C. The role of this flow limiter is to seal the pipe 43 in a leaktight manner.

 The operation is as follows. The internal pressure prevailing in the tank naturally allows the LPG to rise in the hollow 38, this after having passed through the filter 40, the hollow tube 41, the flow limiter 42 and the pipe 43. When the supply solenoid valve 6 receives the order to open from the vehicle engine management system, it releases the seat 39 and authorizes the passage of LPG from the hollow 38 to the second channel 37, then to the engine following route 36, 35 , 8, 34. When the engine is no longer supplied with fuel, the management system orders the supply solenoid valve 6 to come to bear on the seat 39 and prohibit the passage of LPG.

 In FIG. 6A, the limiter 42 comprises a body 60 screwed into the body 2 and connected to the tube 41 by a sleeve 61 and having a longitudinal channel 62 for communication with the pipe 43 of the body 2. The body 60 is supported on a piston 63 subjected to the action of a spring 64. In the figure, it can be seen that the piston 63 is pierced with a first bore 65 at the bottom of which bears the spring 64 and a second bore 66 of smaller diameter, both bores allowing circulation of the

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 LPG between the sleeve 60 and the pipe 43. The spring 64 constantly applies the piston 63 to the top of the sleeve 60 by means of a system of notches in slots. In FIG. 6B, it can be seen that the piston 63 has a square cross-section making it possible to create four free veins 67 between the latter and the body 2. In FIG. 6C, it can be seen that the piston 63 is released from the end of the sleeve 60 and that the bore 66 is provided with a nozzle 68. We can still see the notches 69 in slots made on the sleeve 60.

 The operation of the limiter is as follows. If the pressure difference upstream at the level of the pipe 43 and downstream of the piston 63 at the level of the channel 62 is less than the setting of the spring 64, the piston 63 is kept open, pressed against the tops of the notches in slots 69 as shown in Figure 6A. The LPG is drawn from the tank through the draw-off rod 41, passes through the channel 62 then through the notches in slots 69 and finally through the four veins 67 to reach the engine supply channel 43, at full flow. This is normal operation. If, on the other hand, the pressure difference is greater than the setting of the spring 64, the piston 63 is no longer held by the spring 64 and is pressed into the bottom of its housing as shown in FIG. 6C. In this configuration the passage of the LPG through the veins 67 is no longer possible and only a reduced flow rate is authorized by the nozzle 68 in the channel 62. An abnormal so-called safety operation is obtained which allows the LPG to escape into the atmosphere following a rupture, for example of a pipe.

 FIG. 7 is a sectional view CC of the polyvalve 1 according to the invention showing more particularly the gauging means 51. This gauging means consists of a rheostatic device connected to the body 2 by a fastener 44. This rheostatic device comprises so

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 classic a float 45 articulated on an arm 46. The latter is connected to a support 47 and can be moved by rotation from a high position of full LPG to a low position of absence of LPG. This support 47 receives a rheostatic track 48 on which slides a conductive pad secured to the arm 46. This principle being known, it is not necessary to describe it in more detail.

 This gauging means 51 is electrically connected to the management means 13 by means of two conductors 49 and 50. These two conductors pass through the body by means of a sealed bulkhead crossing 12 whose purpose is to prevent any exit fuel.

 This figure highlights another characteristic of the invention. Indeed, we note that the body 2 has a shoulder 2a and a seal 2b. This constitution allows the valve 1 according to the invention to be easily installed on any container having a passage in correlation with the diameter of the shoulder 2a.

 The gauging means 51 is intended to supply level information from the tank to the dashboard.

However, it can be used to detect the 80% volume filling setpoint. The management means 13 therefore have either level information delivered by the optical detection means 11, or evolving information delivered by the gauging means 51. The management means 13 then manages the use of the either information or a combination of both.

 A variant of the invention makes it possible to advantageously replace the gauging means 51 and the optical detection means 11 by a resistive system which fulfills both the gauging function and the function of detecting the filling instruction at 80%. This variant is in the general form of a hollow tube fixed to the body 2 and disposed substantially vertically in the tank 4. This hollow tube contains

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 electrical resistors positioned according to a predetermined pattern. An electric current is sent to these resistors, which will cause them to heat up in the gaseous part of the tank. Contact with the LPG in the liquid phase tends to cool the resistors, which makes it possible to reliably determine the level of liquid in the tank 4. Obviously, this system can be combined with the gauging means 51 described above and allow the means management 13 to combine and / or compare the different level information.

 The polyvane according to the invention has the definite advantage of offering interactivity between the different means. Indeed, the body 2 is the single support, which allows a common use of these various means of certain conduits, channels and conduits practiced in the body 2.

 The solenoid valves and the means used on this polyvalve 1 can operate from an energy source either autonomous and integrated by means of management of the functions of the polyvalve, or coming from the vehicle. Their operation is based on a normally closed principle, that is to say that there is current consumption only when using the solenoid valves or the means used on this polyvalve according to the invention.

Claims (14)

 CLAIMS 1. Polyvalve (1) for a container intended to contain a gaseous pressurized fluid, of the LPG type, consisting of a body (2) connected on one side to a filling conduit (24) and on the other to a supply duct (34), characterized in that it comprises an optical detection means (11) of the fluid level and a filling limitation device (9a) in combination with management means (13), of filling (9) of the container, gauging (51) of the fluid and supply (10), integral with the body (2).  2. Polyvalve (1) according to claim 1, characterized in that the optical detection means (11) consists of an infrared sensor (14) connected to the body (2), of an emitter (15), d 'a receiver (18) and an amplifier (23) electrically connected to the management means (13).  3. Polyvalve (1) according to claim 1 or 2, characterized in that the filling means (9) consists of a filling solenoid valve (5) controlled by the filling limitation device (9a), said solenoid valve being connected to the body (2) and controlled by the management means (13), this structure cooperating to stop filling according to a set point.  . 4. Polyvalve (1) according to claim 3, characterized in that the filling limitation device (9a) comprises: - a channel (29) connected to the container by means of a non-return valve (30), - a duct (25) connected to the filling duct (24), - a piston (27) for closing the channel (29) and delimiting a cavity (32) with the filling solenoid valve (5), - and means for control of said piston.  5. Polyvalve (1) according to claim 4, characterized in that the control means comprise: <Desc / Clms Page number 15>  - a first pipe (31) through the piston (27) connecting the cavity (32) to the channel (29), the filling solenoid valve (5) obstructing said pipe, - a second pipe (33) connecting the cavity ( 32) to the pipe (25).

 6. Polyvalve (1) according to claim 5, characterized in that the pressure drop of the first pipe (31) is less than that of the second pipe (33), to push back the piston (27) when the solenoid valve of filling (5) is open and allow the passage of the fluid directly from the conduit (25) to the channel (29).  7. Polyvalve (1) according to claim 6, characterized in that the supply means (10) is constituted by a supply solenoid valve (6) controlled by the management means (13) to put in communication, through body (2), the drawing device with the supply conduit (34).  8. Polyvalve (1) according to claim 7, characterized in that the drawing device comprises a hollow tube (41) connecting a filter (40) to a flow limiter (42) integral with the body (2).  9. Polyvalve (1) according to claim 8, characterized in that the gauging means (51) consists of a rheostatic float device connected to the management means (13) to deliver a level indication to the vehicle dashboard .  10. Polyvalve (1) according to one of the preceding claims, characterized in that the management means (13) stops filling either with the optical detection means (11) or with the gauging means (51).  11. Polyvalve (1) according to one of the preceding claims, characterized in that the body (2) comprises internal conduits, channels and conduits necessary for the transit of the fluid in the filling means (9) and <Desc / Clms Page number 16>  supply (10).  12. Polyvalve (1) according to one of the preceding claims, characterized in that the management means (13) receives, manages and transmits the information necessary for the operation of the polyvalve and integrates an autonomous energy source for electrically supplying the optical detection means (11), the filling means (9), the supply means (10), the gauging means (51).  13. Polyvalve according to claim 8, characterized in that the flow restrictor (42) consists of a piston (63) integrated in the body (2) between the pipe (43) and the drawing pipe (41) subjected by the action of a spring (64) to close the pipe (43) in the event of the said drawing pipe breaking.  14. Polyvalve according to claim 13, characterized in that the piston (63) is provided with a nozzle (68) allowing a controlled evacuation of the gaseous fluid.