FR2812247A1 - Liquefied petroleum gas feed for motor vehicle engine has sub tank with filter and flow control electro valve - Google Patents

Abstract

The liquefied petroleum gas feed (2) for a motor vehicle engine has a liquefied gas sub tank (2a) interposed between the main tank (1) and the vehicle engine via connectors (3,5) and incorporating a safety circuit (20). The tank has a filter (24), a feed electro valve (23) and a tank level sensor (29). The sub tank has a pot (14) closed by a lid (15) and sealed by a gasket (16).

Description

The technical sector of the present invention is that of the reserves of

  fuel for vehicles running on liquefied petroleum gas (LPG). Self-propelled handling equipment is a significant consumer of LPG, mainly through the use of C13 type propane cylinders or a

  on-board tank supplied by a private station. Today, some vehicles are fitted with an end of bottle witness kit. This is basic equipment which,

  through an indicator located on the dashboard, indicates to the user that the bottle is almost empty. As soon as this light comes on, there is generally only around thirty seconds of operation before the truck stops completely. This period15 is obviously too short to complete the operation in progress and then replace the bottle. The user is then obliged to manually transport a full bottle. This type of indicator generally works on a pressure balancing principle. It detects a pressure drop20 which goes hand in hand with the decrease in the level of LPG in the source. However, this system is not very reliable because, whether the remaining amount of LPG is ten liters or one milliliter, the pressure will be the same. Therefore, the pressure will drop just when there is no more LPG in the bottle. This drawback leads the user to change the bottle prematurely, the entire contents of the bottle are therefore not consumed and the remainder constitutes

  then a significant source of waste.

  In addition, impurities and particles are present in the bottles and they affect the functioning of the

handling equipment.

  In addition, the increase in temperature causes an increase in pressure of the LPG which can deteriorate certain elements of the supply device. French standard NF H 96-301-1 requires the installation of a pressure relief valve to combat these degradations and avoid

any risk of explosion.

  The object of the present invention is therefore to provide means making it possible to overcome the aforementioned drawbacks by providing sufficient reserve to move around and change the empty source, to ensure filtration of the LPG and to increase the level of safety of the whole feeding device. Another object of the invention is to group all the functions reliably at the level of a single accessory.

  to which an LPG supply from a vehicle must respond.

  The subject of the invention is therefore a supply device intended for vehicles operating with the aid of liquefied petroleum gas (LPG) taken from a source, characterized in that it comprises a reserve of LPG inserted between the source and the vehicle using connection means and incorporating a safety system, a filter element, a supply solenoid valve and a

  reserve level detector.

  According to one embodiment, the reserve consists of a tank closed by a cover and sealed by a seal. According to a characteristic of the invention, the security system, the filtration element, the solenoid valve and the level detector are integral with the cover to be

controlled by LPG pressure.

  According to another embodiment, the reserve comprises a tube intended for the circulation of the LPG, arranged substantially longitudinally and secured to one end of the cover and to the other end of the filtration element. Advantageously, the filtration element is supported

on the bottom of the tank.

  According to yet another embodiment, the connection means are fixed to the cover to delimit an LPG inlet orifice connected to the source, a orifice

  LPG outlet connected to the vehicle and the internal tube.

  Advantageously, the solenoid valve is arranged so as to control the passage of LPG from the hollow tube towards the orifice of

gas outlet.

  According to yet another embodiment, the filtration element consists of a magnetic retention means

  metal particles and a filter.

  According to yet another embodiment, the security system consists of a safety valve calibrated to

about 27,105 Pascals.

  According to yet another embodiment, the level detector is actuated to indicate the drop in level of LPG contained in the reserve in the absence of pressure in the source. A very first advantage of the supply device according to the invention lies in the fact that the user is warned before the truck stops completely, the use of the reserve allowing him to complete the operation in progress,

then change the source.

  Another advantage lies in the significant lowering of the maintenance costs of these vehicles, thanks to the filtration incorporated in the supply device.

according to the invention.

  Another advantage is the increased level

  safety in the use of LPG fuel.

  Another advantage lies in the maximum use of the bottles, thus avoiding waste of LPG, - the bottle is only replaced as soon as it is completely empty.30 Other features, details and advantages the invention will emerge more clearly on reading the

  description given below as an indication in relation

  with drawings in which: - Figure 1 is a diagram illustrating an example of installation of the device according to the invention, - Figure 2 is a sectional view of the device according to the invention, - Figure 3 is a view of above the device according to one invention, - Figure 4 is a sectional view AA of the device illustrating the supply solenoid valve and the gas outlet. In Figure 1, there is shown a diagram illustrating the location of the supply device 2 according to the invention between a source 1 containing liquefied petroleum gas (LPG) and a vehicle whose engine is shown 9. The source is for example constituted by a C13 type bottle containing LPG and connected to the device 2 by a gas inlet pipe 3 constituting a connection means. A distinction is made between the supply solenoid valve 10 conventionally controlled by means of a conductive circuit 7 by the management system 4 of the engine 9. The supply device 2 controls a warning light 12 located on a dashboard 13 of the vehicle by means of a conductor 11. This device 2 is also connected at the gas outlet by a line 5 to the vapor pressure regulator 6, connected via a line 5a to a system

  8 to distribute the LPG to the engine 9 through the intake manifold 9a. The structure of the elements shown is conventional and there is no need to illustrate it in more detail.

  In Figure 2, there is shown a section of the supply device 2 on which there is a tank 14 of substantially cylindrical shape capped by a cover 15 and sealed by a seal 16 of known type. This assembly more specifically constitutes reserve 2a. This cover 15 is held in place by bolts 17 and cooperates perfectly with the tank 14 by means of a shoulder 19. The gas is entered through the cover by means of an orifice 18 tapped for example at pitch one quarter gas and into which the connection means 3 is screwed. A safety valve 20 is screwed through the cover 15 and is sealed by a seal 21. It is of course adjustable by means of an adjustment stud 21a acting directly on a valve (not shown) and on a spring 21b. In operation, this valve communicates the interior of the tank 14 with the external environment. The cover 15 receives, in the vicinity of its central part, a hollow tube 22 connecting the internal end of the solenoid valve 23 to a filtration element 24 disposed at the bottom of the tank 14. This element consists of a support mounted tight and integral relative to the hollow tube 22 and a mechanical filter 26 integrated in this support. The filter is held in place for example by screwing according to the quarter-turn principle and is sealed by a seal 27. This filter 26 receives, at its center and in the axis of the hollow tube 22, a magnetic means 28 for retaining metallic particles which could for example be a magnet. A level detector 29 is made integral with the shoulder 19. It consists of an axis 30 to which a float 31 is coupled. An electrical contact (not shown), for example of the ILS type, is provided for locating the high level of the float. The axis of course serves as a translation guide for the float 31. It is understood that the gas arriving through the connector 3 fills the tank, the level of which rises, driving the float which closes the contact. The gas is taken from the tank to supply the engine through the tube 22, being freed of its metallic impurities by the magnet and of the other impurities by the filter. Thus, the device according to the invention makes it possible to gather at the level of a single element in a compact manner all the necessary accessories.

  to the LPG supply function of a vehicle. It is therefore an appreciable advantage of high reliability.

  Figure 3 is a top view of the cover of the supply device according to the invention in which there are the fixing bolts 17 distributed on the periphery of this cover 15. There is also a safety valve 20, the level detector 29 and the gas inlet orifice 18. Symmetrically with this orifice 18, there is seen an orifice 32 for the outlet of the gas. The solenoid valve 23 is able to slide in a conduit 33 to control the outlet of the gas through the orifice 32. The safety valve 20 which communicates with the interior of the tank is capable of reacting to an increase in pressure according to the calibration adopted at the outset. FIG. 4 shows the arrangement of the solenoid valve 23 relative to the cover 15 and to the duct 33. It is for example screwed into the cover 15 and communicates with the hollow tube 22. This solenoid valve is arranged so as to allow or prohibit the passage gas from the hollow tube 22 to the orifice 32. In fact, the solenoid valve 23 closes the

  conduit 33a by applying its end to a seat 33b.

  The operation of the supply device is as follows. The LPG from the bottle 1 enters the device according to the invention through the corresponding orifice 18

  at the gas inlet. The tank 14 is filled with liquid gas.

  When it is full, the float 31 comes to set itself in the high position. The indicator light 12 on the dashboard 13 does not give a signal. In operation, the liquid gas charged with impurities and metallic particles coming from the bottle is taken up at the bottom of the tank 14. This liquid gas 25 therefore bathes the magnet 28 which retains the metallic particles, then it passes through the filter 26 to rise in the hollow tube 22. The solenoid valve 23 controlled by the management system 4 of the engine 9 makes it possible to send the LPG to

  the gas outlet orifice 32 then to the pressure reducer 6.

  When the bottle 1 is empty, the level in the tank 14 drops and the float 31 switches to the low position where it actuates the electrical contact. The information is then delivered by the thread 11 to the indicator light 12 located on the dashboard 13. The user is now warned that the bottle is empty and that he is starting his reserve, giving him, for example, an autonomy of about ten minutes. He can therefore make the necessary arrangements

  to replace the bottle 1. This avoids premature replacement of the bottle still containing fuel, waste is therefore no longer possible.

  On the other hand, with the expansion of the gas under the effect of heat, the pressure inside the tank increases and can become dangerous. The safety valve 20 is calibrated at around 27.105 Pa, the bottle 1 and the entire device according to the invention being designed to withstand a pressure of at least 30.105 Pascals. As soon as this value is reached, a fraction of LPG is evacuated to the outside until a normal safety situation is restored. This safety valve 20 can be equipped with a degassing pipe (not shown) to channel the

gas to the ground.

  The solenoid valve 23 incorporated in the device according to the invention replaces the solenoid valve usually placed at the level of the pressure reducer in conventional embodiments, and has the main advantage of reducing the installation of

this regulator.

  Finally, note that the main elements of the device being fixed to the cover 15, so-called corrective but also preventive interventions are greatly facilitated. Thus, removing the cover allows direct access to the elements since they are there.

  set. We can therefore very easily disassemble one of these

  this. Cleaning the filter element is quick

  performed since it is extracted by simple rotation.

Claims (10)

  1. Supply device (2) intended for vehicles operating using liquefied petroleum gas (LPG) taken from a source (1), characterized in that it comprises a reserve (2) of LPG interposed between the source (1) and the vehicle engine using connection means (3,) and incorporating a security system (20), a filtration element (24), a supply solenoid valve (23) and a reserve level detector (29). 10 2. Feeding device (2) according to claim 1, characterized in that the reserve (2) consists of a tank (14) closed by a cover (15) and sealed by a seal (16).   3. Supply device (2) according to claim 2, characterized in that the security system (20), the filter element (24), the solenoid valve (23) and the level detector (29) are integral with the cover (15)   to be controlled by LPG pressure.   4. Feeding device (2) according to claim 3, characterized in that the reserve (1) comprises a tube (22) intended for the circulation of LPG, disposed substantially longitudinally and integral with one end of the cover   (15) and at the other end of the filter element (24).   5. Feeding device (2) according to claim 4, characterized in that the filtration element (24) is in support on the bottom of the tank.   6. Feeding device (2) according to claim 4 or 5, characterized in that the connection means (3,) are fixed to the cover (15) to delimit an orifice (18) of LPG inlet connected to the source (1), an LPG outlet orifice (32) connected to the vehicle and to the tube internal (22).   7. Supply device (2) according to claim 6, characterized in that the solenoid valve (23) is arranged so as to control the passage of LPG from the hollow tube (22) to the gas outlet orifice (32).   8. Feeding device (2) according to any one of the preceding claims, characterized in that   the filter element (24) consists of a magnetic means (28) for retaining metal particles and a filter (26).   9. Feeding device (2) according to any one of the preceding claims, characterized in that the   safety system (20) consists of a safety valve calibrated to approximately 27.105 Pascals.   10. Feeding device (2) according to claim 4, characterized in that the level detector (29) is actuated to indicate the drop in level of LPG contained in the reserve (2a) in the absence of fuel in the source (1).