Improved valve for the remote inflation of a tire of a vehicle wheel and vehicle comprising a remote inflation system comprising at least one such valve

Abstract

The invention relates to a valve (1) for the remote inflation of a tire of a vehicle wheel, a reservoir capable of storing a pressurized gas being embedded in the wheel, the valve (1) comprising an inlet orifice (5) for a pilot pressure intended to be connected to a pressure source, an inflation-deflation orifice (7) intended to be connected to a tire, an exhaust orifice (8) intended to be connected to the outside of the valve (1) and an orifice for communication with the reservoir (6) intended to be connected to the reservoir, the valve (1) comprising pressure-sensitive pilot means (9a-9c, 10a-10c, 49) configured and arranged to be capable of being moved under the effect of the pilot pressure so as to adopt a rest position, an inflation position and a deflation position,characterized in that said pressure-sensitive control means are also configured and arranged to adopt a tank filling position. Figure to be published with the abstract: Figure 5.,

Description

Title of the invention: Improved valve for the remote inflation of a tire of a vehicle wheel and vehicle comprising a remote inflation system comprising at least one such valve

[0001] The technical field of the invention is that of remote inflation, and in particular of remote inflation of a tire of a wheel equipped with a pressurized gas reservoir.

[0002] Such a wheel equipped with a pressurized gas reservoir is notably described in French patent FR2879128.

[0003] The present invention relates to a valve for the remote inflation of a tire of a vehicle wheel, which wheel is equipped with a pressurized gas reservoir, and a motor vehicle comprising a remote inflation system comprising at least one such valve.

[0004] Generally speaking, remote inflation systems allow the internal pressure of a vehicle's tires to be modified directly from the vehicle's passenger compartment.

[0005] The addition of such a system is particularly useful for vehicles intended to travel on different types of ground, in particular those likely to alternate between phases of driving in a field, where low pressures are recommended for good grip and reduced slippage, and phases of driving on the road, where higher pressures are necessary, both for the grip of the tires, the efficiency of traction and good control of trajectories.

[0006] Such a system is also useful for vehicles likely to carry different loads and / or likely to travel at different speeds.

[0007] By allowing the tire pressure to be varied to adapt to the surfaces on which the vehicle is traveling, the loads it is carrying and the speed of travel of the vehicle, such a remote inflation system makes it possible to reduce tire wear as well as the vehicle's fuel consumption, allowing substantial savings and a reduction in the environmental impact of operation.

[0008] Remote inflation systems are therefore useful in many fields of application, particularly in agricultural, military, civil and rally-type vehicles. The most common application concerns agricultural tractors, but all-terrain vehicles in general are affected by this type of system.

[0009] There are many remote inflation systems comprising simple valves and, possibly, rotating joints, to supply air to the wheel tires with an on-board compressor. Such systems are disclosed in particular in French patents FR2872087 and FR3020597.

[0010] However, with such remote inflation systems, the time required to inflate and deflate a tire is significant, and can in particular exceed 15 minutes when it comes to an agricultural tire.

[0011] However, it is desirable that the adaptation of the pressure according to the state of the terrain traveled, the load transported and the speed of the vehicle be almost instantaneous.

[0012] For this purpose, there are remote inflation systems comprising a pressurized air reservoir mounted on the vehicle wheel and a specific valve allowing the pressurized air contained in the reservoir to be injected into the tire.

[0013] Such a remote inflation system is disclosed in particular in French patent FR3086577. In particular, the specific valve described in this patent FR3086577 is a four-way valve capable of taking several positions, in which it fluidly connects two elements among the outlet valve of the tank, the internal volume of the tire and the exterior of the tire. Thus, the 4-way valve allows, depending on its position, either to increase the pressure in the tire or to reduce the pressure in the tire. The 4-way valve is also capable of measuring the respective internal pressures of the tire or the tank by putting the tire or the tank in communication with a pressure sensor. This system further comprises an inlet valve allowing the tank to be fluidly connected to an air compressor carried by the vehicle in order to allow the tank to be filled.

[0014] This system has the advantage of allowing overpressure air to be stored in the wheel reservoir and thus allowing the pressure in the tires to be increased very quickly when an adjustment is required. In other words, such a system makes it possible to considerably reduce the time taken to inflate a tire.

[0015] However, the specific valve described in this patent FR3086577 does not allow control of both the inflation and deflation of the tire and the filling of the tank.

[0016] It is therefore the aim of the present invention to propose a specific valve, controlled by pressure, capable of ensuring the inflation and deflation functions as well as the tank filling function.

[0017] The solution according to the present invention is therefore based on an improved valve allowing, depending on a pilot pressure, either to fill the tank with pressurized air supplied by a pressure source of the vehicle, such as a compressor, or to inflate the tire by releasing the pressurized air from the tank, or to deflate the tire.

[0018] The invention thus relates to an improved valve for the remote inflation of a tire of a vehicle wheel, a reservoir capable of storing a gas under pressure being embedded in the wheel, the valve being intended to be interposed between a pressure source capable of generating a pilot pressure and the wheel, the valve comprising four orifices, namely an inlet orifice for the pilot pressure intended to be connected to the pressure source, an inflation-deflation orifice intended to be connected to the internal volume of the tire, an exhaust orifice intended to be connected to the outside of the valve and an orifice for communication with the reservoir intended to be connected to the reservoir, the valve comprising, in a body provided with said four orifices, pressure-sensitive control means configured and arranged to be able to be moved under the effect of the control pressure so as to adopt: - a rest position in which the control means ensure closure of the passages between said orifices; - an inflation position in which said control means ensure communication between the orifice for communication with the reservoir and the inflation-deflation orifice;- a deflation position in which said control means ensure communication between the inflation-deflation orifice and the exhaust orifice; characterized in that said pressure-sensitive control means are also configured and arranged to adopt a tank filling position in which said control means ensure communication between the intake orifice and the orifice for communication with the tank.;

[0019] The improved valve according to the invention therefore makes it possible to transfer the pressurized gas from the tank to the tire for inflation, while also making it possible to perform the functions of filling the tank and deflating the tire. In addition, the valve according to the invention is controlled by the same flow of gas as that which fills the pressurized tank in the filling position.

[0020] In a particular embodiment, the piloting means comprise first, second and third piston assemblies, each piston assembly being axially movable in a housing in fluid communication with the pilot pressure inlet orifice via a piloting circuit successively connecting each housing to said inlet orifice, the first, second and third piston assemblies being sensitive, respectively, to a first, second and third pilot pressure, the first pilot pressure being lower than the second pilot pressure and the second pilot pressure being lower than the third pilot pressure.

[0021] Such a valve is therefore simple and reliable.

[0022] Preferably, the first, second, and third piston assemblies are configured and arranged such that, in use, when the first pilot pressure is delivered through the inlet port, the piston assemblies are placed in the deflation position, when the second pilot pressure is delivered through the inlet port, the piston assemblies are placed in the inflation position, and when the third pilot pressure is delivered through the inlet port, the piston assemblies are placed in the filling pressure, the third pilot pressure being the tank filling pressure.

[0023] Preferably, each piston assembly comprises a closure element having a first closed axial end, on the control circuit side, and a second opposite open axial end, and an elastic return member secured to the body, on the second axial end side, and to the closure element, said elastic return member being functionally associated with the closure element so as to return it to the rest position, the stiffness of the elastic return member of the first piston assembly, called the first stiffness, being less than the stiffness of the elastic return member of the second piston assembly, called the second stiffness, and the second stiffness being less than the stiffness of the elastic return member of the third piston assembly, called the third stiffness.

[0024] Preferably, the elastic return members comprise compression springs.

[0025] Preferably, each closing element is a hollow cylindrical body slidably mounted in a cylindrical housing, the hollow cylindrical body being connected to the body of the valve by an axial rod capable of being received in the hollow cylindrical body, each hollow cylindrical body having a dumbbell shape, in other words comprising a central circumferential groove arranged between two bearing surfaces.

[0026] Preferably, the housings in which the piston assemblies are housed extend parallel to each other, and perpendicular to the axes of the four orifices.

[0027] Advantageously, the first, second and third stiffnesses are chosen such that the first pilot pressure is approximately 1.8 bar, the second pilot pressure is approximately 3.4 bar and the third pilot pressure is greater than or equal to 6 bar.

[0028] Preferably, each elastic return member comprises two concentric and coaxial springs, including an outer spring and an inner spring, the stiffnesses of the first, second and third outer springs being different and the stiffnesses of the first, second and third inner springs being different.

[0029] Advantageously, the valve body is a body in at least two parts comprising a housing and a cover detachably fixed to the housing by removable fixing members, in particular screws.

[0030] Such mounting of the valve body allows easy access to the piston assemblies.

[0031] The present invention also relates to a motor vehicle comprising at least one wheel having a tire defining an interior volume; for the or each wheel, a reservoir capable of storing a gas under pressure; and a system of remote inflation comprising a pressure source carried by the vehicle, characterized in that the remote inflation system further comprises, for the or each wheel, a single valve as defined above, in which valve the intake orifice is connected to the pressure source, the inflation-deflation orifice is connected to the interior volume of the tire, the exhaust orifice is connected to the outside of the valve and the orifice for communication with the reservoir is connected to the reservoir, the remote inflation system further comprising a control module coupled to the or each valve and to the pressure source.

[0032] Thus, the vehicle according to the invention makes it possible to store a gas under pressure in the tank of the or each wheel, and to vary the pressure in the or each tire as well as to fill the or each tank via the control of a single valve for the or each wheel.

[0033] The pressure source may be a vehicle air generation source or an on-board gas compressor.

[0034] The vehicle may be an agricultural vehicle, a military vehicle, a rally-type vehicle or a civilian vehicle.

[0035] Preferably, the control module comprises an electropneumatic distribution box connected to a control console.

[0036] The control panel, which is the interface between a user and the remote inflation system, can be arranged in the passenger compartment of the vehicle.

[0037] The electropneumatic distribution box makes it possible to process the instructions given by the user, in particular the driver of the vehicle, via the control panel and to control the valve.

[0038] The control panel can be connected to the electropneumatic distribution box by a direct electrical connection.

[0039] Preferably, the remote inflation system further comprises, for the or each wheel, a first pressure sensor capable of measuring a pressure in the interior volume of the tire and a second pressure sensor capable of measuring a pressure in the reservoir.

[0040] Each pressure sensor can transmit the pressure measurement data to the control panel via a wireless connection.

[0041] Such a system allows the user to manage the pressure in the or each tire of the vehicle from the passenger compartment and to have permanent knowledge of the pressure of the tire(s) and the pressure in the or each associated tank.

[0042] The present invention will be better understood on reading the following description of a particular embodiment, a description made in light of the appended drawings, drawings in which:

[0043] [Fig.l] is an exploded perspective view of a valve according to the invention;

[0044] [Fig.2] is a longitudinal sectional view of the valve according to the invention, the means of piloting being in the rest position;

[0045] [Fig.3] is a longitudinal sectional view of the valve according to the invention, the control means being in the deflation position;

[0046] [Fig.4] is a longitudinal sectional view of the valve according to the invention, the control means being in the inflation position;

[0047] [Fig.5] is a longitudinal sectional view of the valve according to the invention, the control means being in the reservoir filling position; and

[0048] [Fig.6] is a schematic view of a vehicle according to the invention, showing the integration of a remote inflation system comprising at least one valve according to the invention in a tractor-type vehicle.

[0049] If we first refer to Figures 1 to 5, we can see that a valve 1 is shown there according to a preferred embodiment of the present invention, which valve 1 is intended to be integrated into a remote inflation system S applied to the adjustment of the pressure of the tires 2 of a vehicle V.

[0050] The valve 1 according to the present invention is particularly suitable for application in the civil field, in particular agricultural. However, the valve 1 can find its application on a wheeled military vehicle.

[0051] Generally speaking, the valve 1 is intended to be integrated into a vehicle V comprising at least one tire 2 capable of being inflated and a reservoir 3 capable of storing a gas under pressure and associated with the tire 2.

[0052] The valve 1 according to the present invention comprises a valve body 4 with four orifices 5, 6, 7, 8 and, inside the valve body 4, pressure-sensitive control means.

[0053] As can be seen in Figures 2 to 5, the valve body 4 is a hollow body provided with four orifices 5-8, namely an inlet orifice 5, an orifice for communication with the reservoir 6, an inflation-deflation orifice 7 and an exhaust orifice 8.

[0054] This valve body 4 comprises a housing 40 and a cover 41 removably fixed to the housing 40, in particular by means of four screws 42. The housing 40 has the shape of a parallelepiped with rectangular bases, in other words, the housing 40 has six rectangular walls delimiting a first interior space. The cover 41 has a rectangular section and has a bottom wall 41a and four side walls delimiting between them a second interior space.

[0055] The intake orifice 5 is intended to be connected, by a pneumatic line, to a pressure source 11 capable of generating a pilot pressure. The inflation-deflation orifice 7 is intended to be connected, by a pneumatic line, to the interior volume of a tire 2. The exhaust port 8 is intended to open outside the valve 1. The port for communication with the tank 6 is intended to be connected, by a pneumatic line, to the tank 3.

[0056] Inside the valve body 4 three passages are defined, namely a passage 43 (the path of which is shown in dotted lines in [Fig. 3]) between the inflation-deflation orifice 7 and the exhaust orifice 8, a passage 44 (the path of which is shown in dotted lines in [Fig. 4]) between the orifice for communication with the reservoir 6 and the inflation-deflation orifice 7, a passage 45 (the path of which is shown in dotted lines in [Fig. 5]) between the intake orifice 5 and the orifice for communication with the reservoir 6.

[0057] Inside the valve body 4 are also defined first 46, second 47 and third 48 axial housings each having a first axial end opening into a passage 49 (the path of which is shown in Figures 3 to 5) communicating with the inlet orifice 5, and a second closed axial end. The passage 49 defined between the inlet orifice 5 and each of the housings 46, 47, 48 is called the pilot circuit 49.

[0058] Each housing 46, 47, 48 extends through an orifice provided in the wall of the housing 40 separating the first and second spaces, and up to the bottom wall 41a of the cover 4L. Thus, the second axial end of each housing 46, 47, 48 is closed by the bottom wall 41a.

[0059] In the embodiment shown, the housings 46, 47, 48 are cylindrical, the three housings 46, 47, 48 being of the same length and possibly of the same diameter or not. These three housings 46, 47, 48 extend in the same plane, along longitudinal axes which are parallel to each other and perpendicular to the bottom wall 41a. The housings 46, 47, 48 are regularly spaced from each other. The plane in which the housings 46, 47, 48 are located is offset from the plane passing through the center of the bottom wall 41a.

[0060] The four orifices 5-8 of the valve body 4 are circular orifices formed in two opposite walls of the housing 40 which are perpendicular to the bottom wall 41a. The axis of each orifice 5-8 is orthogonal to the longitudinal axis of each housing 46-48 and extends in a plane parallel to the plane of the housings 46-48. The inlet orifices 5 and the orifices for communication with the reservoir 6 are arranged through the same wall of the housing 40, namely the wall on the first housing side 46, and are spaced from each other along the length of this wall and offset from each other across the width of this wall. In particular, the intake orifice 5 is closer to the bottom wall 41a than the orifice for communication with the reservoir 6, and the orifice for communication with the reservoir 6 is offset from the plane of the housings 46-48. The inflation-deflation orifices 7 and exhaust orifices 8 are arranged across the same wall of the housing 40, namely the third housing side wall 48, which wall is opposite that comprising the intake orifice 5. The inflation-deflation orifice 7 is located opposite the orifice for communication with the reservoir 6. The exhaust orifice 8 is spaced from the inflation-deflation orifice 7 along the length of this wall and is offset relative to it across the width of this wall.

[0061] The passage 43 between the inflation-deflation orifice 7 and the exhaust orifice 8 is a tubular passage which passes through the third housing 48. This passage 43 has two 90-degree bends located in the same plane as well as a bent zone, at the level of the third housing 48, making it possible to pass from the plane of the inflation-deflation orifice 7 to the plane of the exhaust orifice 8. The tubular passage 44 between the orifice for communication with the reservoir 6 and the inflation-deflation orifice 7 passes through the second housing 47 and has four 90-degree bends located in the same plane, as well as two bent zones at the level of the second housing 47. The tubular passage 45 between the intake orifice 5 and the orifice for communication with the reservoir 6 passes through the first housing 46.This passage 45 has two 90-degree bends located in the same plane as well as a bent zone, at the level of the first housing 46, making it possible to pass from the plane of the intake orifice 5 to the plane of the orifice for communication with the tank 6. The control circuit 49 is arranged in the same plane as that containing the longitudinal axes of the housings 46-48.

[0062] The pressure-sensitive control means comprise three piston assemblies 9a-9c, 10a-10c received in the housings 46-48, as well as the control circuit 49.

[0063] These control means are configured and arranged to adopt, selectively, as a function of a control pressure delivered in the control circuit 49 through the intake orifice 5, one of the four positions among a rest position ([Fig.2]) in which the passages 43-45 between the orifices 5-8 are closed, a deflation position ([Fig.3]) in which the passage 43 between the inflation-deflation orifice 7 and the exhaust orifice 8 is open, the other passages 44, 45 between the orifices being closed, an inflation position ([Fig.4]) in which the passage 44 between the orifice for communication with the reservoir 6 and the inflation-deflation orifice 7 is open, the other passages 43, 45 between the orifices being closed, and a filling position of tank ([Fig.5]) in which the passage 45 between the intake orifice 5 and the orifice for communication with the reservoir 6 is open, the other passages 43, 44 between the orifices being closed.

[0064] As can be seen more particularly in [Fig. 1], each piston assembly 9a-9c, 10a-10c comprises a closing element 9a, 9b, 9c and an elastic return member 10a, 10b, 10c.

[0065] The closing elements 9a-9c of each of the piston assemblies 9a-9c, 10a-10c are of the same structure, but their diameters may be different, depending on the diameter of the housings 46-48. Each closing element 9a-9c is a single-piece hollow longitudinal body having a first closed axial end 90 and a second open axial end 91. This body is a cylindrical body comprising two cylindrical bearing surfaces 92 on either side of a cylindrical groove 93. The two bearing surfaces 92 have the same external diameter, greater than the external diameter of the groove 93, and substantially equal to the diameter of the respective housing 46-48. Thus, the closing element 9a-9c is able to slide in the housing 46-48, along the longitudinal axis of the housing 46-48.The travel of the closing element 9a-9c in its housing 46-48 is limited, on the side of its first closed end 90, by a radial seat 94 formed between the side wall of the housing 46-48 and the control circuit 49, and on the side of its second open end 91, by the bottom wall 41a of the cover 4L. The length of the closing element 9a-9c is strictly less than the length of its housing 46-48. For each closing element 9a, 9b and 9c, sealing elements 400, 401 and 402, such as for example O-rings, are also provided so as to ensure a seal between the respective closing element 9a-9c and the respective housing 46-48. For example, four sealing elements 400 can be provided for the closing element 9a, four sealing elements 401 for the closing element 9b, and four sealing elements 402 for the closing element 9c.

[0066] As can also be seen in [Fig.l], each elastic return member 10a-10c comprises two springs, namely an outer spring 100a-100c and an inner spring 101a-101c, and an axial rod 102.

[0067] The axial rod 102 is a rigid rod comprising a cylindrical head and a cylindrical rod body with a diameter smaller than that of the head. The rod 102 is fixed to the bottom wall 41a of the cover 41 by means of a screw 103 passing through a bore provided in the bottom wall 41a and screwed into a bore provided in the head. In other words, the head of the screw 103 is accessible from outside the valve body 4 and the threaded rod of the screw 103 is fixed to the rod 102. The longitudinal axis of the rod 102 is coaxial with the central longitudinal axis of the housing 46-48. The diameter of the rod 102 is less than the inner diameter of the closure element 9a-9c, so that the rod 102 extends inside the hollow body of the closure element 9a-9c from its second open axial end 91.

[0068] The inner spring 101a-101c is mounted around the body of the rod 102 and has one end resting on the head of the rod 102 and one end resting on the inner wall of the closing element 9a-9c. This inner spring 101a-101c is of the helical compression spring type which urges the closing element 9a-9c towards its rest position, in other words opposite the bottom wall 41a. The axial rod 102 and the inner spring 101 a-101c of each of the piston assemblies 9a-9c, 10a-10c are of the same structure, but the stiffnesses of the three inner springs 101a-101c may be different, depending on the stiffnesses of the three outer springs 100a-100c to obtain the different positions of the closing elements 9a-9c which will be described below.

[0069] The outer spring 100a-100c is received in the space formed between the inner spring 101a-101c and the inner wall of the closing element 9a-9c, the outer diameter of the outer spring 100a-100c being slightly smaller than the inner diameter of the cylindrical bearing surfaces 92. The outer spring 100a-100c is coaxial with the inner spring 101a-101c. The outer spring 100a-100c has one end bearing on the bottom wall 41a and one end bearing on the inner wall of the closing element 9a-9c. This outer spring 100a-100c is also of the helical compression spring type. The outer springs 100a-100c of the three piston assemblies 9a-9c, 10a-10c are different, in particular, have different stiffnesses.More specifically, the stiffness of the first outer spring 100a associated with the closing element 9a of the first piston assembly 9a, 10a is less than the stiffness of the second outer spring 100b associated with the closing element 9b of the second piston assembly 9b, 10b, and the stiffness of the second outer spring 100b is less than the stiffness of the third outer spring 100c associated with the closing element 9c of the third piston assembly 9c, 10c. Thus, the force required to move the first closing element 9a against the associated elastic return member 10a is less than the force required to move the second closing element 9b against the associated elastic return member 10b, which is itself less than the force required to move the third closing element 9c against the associated elastic return member 10c.

[0070] By way of example, the stiffness of the first outer spring 100a may be chosen such that the first closing element 9a moves axially, inside the first housing 46, against the return force of the associated outer spring 100a and inner spring 101a when a pilot pressure PI at least equal to 1.8 bar is applied, through the pilot circuit 49, to the first closed axial end 90 of this closing element 9a. The stiffness of the second outer spring 100b may be chosen such that the second closing element 9b moves axially, inside the second housing 47, against the return force of the associated outer spring 100b and inner spring 101b when a pilot pressure P2 greater than or equal to 3.4 bars is applied, through the pilot circuit 49, to the first closed axial end 90 of this closing element 9b. The stiffness of the third outer spring 100c can be chosen such that the third closing element 9c moves axially, inside the third housing 48, against the return force of the associated outer spring 100c and inner spring 101c when a pilot pressure P3 greater than or equal to 6 bars is applied, through the pilot circuit 49, to the first closed axial end 90 of this closing element 9c.

[0071] In use, when no pilot pressure is applied in the pilot circuit 49, the three piston assemblies 9a-9c, 10a-10c are urged into the rest position by their elastic return members 10a-10c. In this rest position, as can be seen in [Fig. 2], the outer springs 100a-100c and inner springs 101a-101c are in the relaxed state and the first closed axial end 90 of each closure element 9a-9c is in abutment against the radial seat 94. The three passages 43-45 formed between the orifices 5-8 of the valve 1 are then closed by the closure elements 9a-9c.

[0072] When the tire 2 must be deflated, for example to allow a vehicle V equipped with such a valve 1 to drive on sandy terrain, it is appropriate to place the piston assemblies 9a-9c, 10a-10c in the deflation position, as shown in [Fig. 3]. For this, a pilot pressure PI, here 1.8 bar, called first pilot pressure PI, must be applied via the intake orifice 5, through the pilot circuit 49. Due to the stiffness of the first outer spring 100a, this first pilot pressure PI causes the axial displacement of the first closing element 9a in its housing 46 against the associated springs 100a, 101a, which are then in a first compressed state.This movement of the first closing element 9a, by 18 mm in the direction of the arrow F1, ensures the fluid communication between the inflation-deflation orifice 7 and the exhaust orifice 8, and therefore allows the deflation of the tire 2 towards the outside. Due to the stiffness of the springs 100b, 100c, the second 9b and third 9c closing elements are maintained in the rest position, the other passages 44, 45 between the orifices therefore remaining closed by the second and third closing elements 9b, 9c during the deflation phase of the tire 2. When the deflation of the tire 2 has reached the desired limit, the first pilot pressure PI is no longer applied, and the first piston assembly 9a, 10a is automatically returned to its rest position according to [Fig. 2] by the associated elastic return member 10a.

[0073] When it is necessary to inflate the tire 2, for example to allow a vehicle V equipped with such a valve 1 to drive on hard ground, it is necessary to place the piston assemblies 9a-9c, 10a-10c in the inflation position, as shown in [Fig. 4]. For this, a pilot pressure P2, here 3.4 bars, called second pilot pressure P2, is applied via the intake orifice 5 through the pilot circuit 49, the second pilot pressure P2 then being applied simultaneously to the closed axial ends 90 of the three closure elements 9a-9c.Due to the stiffness of each of the outer springs 100a-100c, this second pilot pressure P2 causes the axial displacement of the first closing element 9a and the second closing element 9b in their respective housing 46 and 47 against the associated springs 100a, 100b, 101a, 101b, while the third closing element 9c remains biased towards its rest position. More precisely, the first closing element 9a is here displaced by 36 mm in the direction of the arrow F1, the associated springs 100a, 101a then being in a second compressed state and the first closing element 9a closing the exhaust orifice 8, and the second closing element 9b is here displaced by 18 mm in the direction of the arrow F2, the associated springs 100b, 101b then being in a first compressed state.These movements ensure fluid communication between the orifice for communication with the reservoir 6 and the inflation-deflation orifice 7, and therefore allow the inflation of the tire 2 from the pressurized gas contained in the reservoir 3. Once a determined inflation pressure threshold has been reached in the tire 2, the second pilot pressure P2 is no longer applied, so that the first and second piston assemblies are automatically returned to their rest position according to [Fig. 2] by the associated elastic return members 100a, 100b, 101a, 101b.

[0074] When it is necessary to fill the reservoir 3 with pressurized gas in order to permanently maintain the reservoir 3 at a determined high pressure, the piston assemblies 9a-9c, 10a-10c should be placed in the filling position, as shown in [Fig. 5]. For this, a pilot pressure P3 greater than or equal to 6 bars, called third pilot pressure P3, is applied to the closed axial ends 90 of the three closure elements 9a-9c via the pilot circuit 49. This high third pilot pressure P3 causes the axial displacement of the first 9a, second 9b and third 9c closure elements in their respective housing 46, 47, 48 against the associated springs 100a-100c, 101a-101c.More specifically, due to the stiffness of each of the outer springs 100a-100c, the first 9a and second 9b closing elements are displaced by 36 mm in the direction of the arrow F1, F2, the associated springs 100a, 100b, 101 then being in a second compressed state. At the end of this displacement of 36 mm, the second axial end 91 of . each of the first 9a and second 9b closing elements is in axial abutment against the bottom wall 41a, in which position the first closing element 9a closes the exhaust orifice 8 and the second closing element 9b cuts the passage 44. In other words, this displacement over a length of 36 mm corresponds to the maximum stroke of the closing elements 9a-9b. The third closing element 9c is displaced by 18 mm in the direction of the arrow F3, the associated springs 100c, 101c then being in a first compressed state. These movements of the three closing elements 9a-9c ensure fluid communication between the inlet orifice 5 and the orifice for communication with the reservoir 6, and therefore allow the filling of the reservoir 3 with the gas at said first pilot pressure PI delivered through the inlet orifice 5. The other passages 43, 44 between the orifices remain closed during the filling phase of the reservoir 3.Once a determined filling pressure threshold has been reached in the tank 3, the third pilot pressure P3 is no longer applied, so that the three piston assemblies are automatically returned to their rest position according to [Fig.2] by the associated elastic return members 100a-100c, 101a-101c.

[0075] The valve 1 according to the present invention is intended to be used in a vehicle V, as shown schematically in [Fig. 6]. This vehicle V is in particular a vehicle intended to roll on ground having rolling conditions that differ from one another, for example a tractor. However, although the motor vehicle V shown in [Fig. 6] is an agricultural vehicle, this vehicle could be any vehicle comprising at least one wheel 12 capable of being inflated and a tank 3 capable of containing a pressurized gas associated with said wheel 12.

[0076] With reference to [Fig.6], the vehicle V comprises a chassis supporting a driver's cabin 13, four wheels 12, four pressurized gas tanks 3 and a remote inflation system S.

[0077] Each wheel 12, namely the two front wheels and the two rear wheels, comprises a tire 2 defining an interior volume intended to contain pressurized gas.

[0078] A tank 3 capable of storing a pressurized gas, for example compressed air, is embedded in each wheel 12. The arrangement of the tank 3 may be similar to that described in French patent FR3086577.

[0079] In the embodiment shown in [Fig.6], the remote inflation system S makes it possible to vary the pressure in the interior volume of the tires 2 of each of the four wheels 12 of the vehicle V. As a variant, the remote inflation system S could make it possible to vary the pressure in the tires 2 of some of the wheels 12, or even of a single wheel 12.

[0080] The remote inflation system S comprises a pressure source 11, a control module 14, 15, and for each wheel 12, a single valve 1 according to the present invention and first and second pressure sensors 16, 17.

[0081] The pressure source 11 is, preferably, a compressor carried by the vehicle V. This compressor 11 is connected to the control module 14, 15 in order to deliver, on command from the control module 14, 15, a flow of pressurized gas, in particular a flow of compressed air, through a pneumatic line fluidically connected to the inlet orifice 5 of each valve 1.

[0082] Each valve 1 according to the invention, in addition to being connected to the compressor 11, is fluidically connected to the internal volume of the associated tire 2 via a pneumatic line connecting the internal volume of the tire 2 to its inflation-deflation orifice 7, is connected to the outside via its exhaust orifice 8, and is connected to the associated reservoir 3 via a pneumatic line connecting the reservoir 3 to its orifice for communication with the reservoir 6. Each valve 1 is pneumatically controlled by the control module 14, 15.

[0083] The control module 14, 15 comprises an electropneumatic distribution box 14 and a control console 15. The control console 15 is positioned in the driver's cabin 13 of the vehicle V so that it can be controlled directly by the driver of the vehicle V, in particular while the vehicle V is in motion. This control console 15 is connected, for example by a wired connection, to the electropneumatic distribution box 14, itself connected to each of the valves 1. Thus, the valves 1 can be controlled remotely, from the driver's cabin 13. Control of the valves 1 is easy and quick, the driver simply having to enter the value of the control pressure to be applied to each valve 1.Depending on the pilot pressure applied, namely either no pilot pressure, or the first PI, second P2 or third P3 pilot pressure, each valve 1 changes configuration and adopts one of its four positions, as shown in Figures 2 to 5.

[0084] For each wheel 12, the first pressure sensor 16 is mounted at the tire 2 so as to measure a pressure in the interior volume of the tire 2, and the second pressure sensor 17 is mounted at the tank 3 so as to measure a pressure in the tank 3. The pressure measurement data measured by these sensors 16, 17 are transmitted to the control panel 15, by a wired or wireless connection. Thus, the control of each valve 1 can be carried out simply and quickly from a comparison of the pressure in the tire 2 with a desired tire pressure value and from a comparison of the pressure in the tank 3 with a desired tank pressure value.

[0085] It is understood that the particular embodiment which has just been described has been given for informational purposes and is not limiting, and that modifications may be made without departing from the present invention.

Claims

Claims

1. Improved valve (1) for the remote inflation of a tire (2) of a wheel (12) of a vehicle (V), a reservoir (3) capable of storing a pressurized gas being embedded in the wheel (12), the valve (1) being intended to be interposed between a pressure source (11) capable of generating a pilot pressure (P1, P2, P3) and the wheel (12), the valve (1) comprising four orifices (5-8), namely an inlet orifice (5) for the pilot pressure (P1-P3) intended to be connected to the pressure source (11), an inflation-deflation orifice (7) intended to be connected to the interior volume of the tire (2), an exhaust orifice (8) intended to be connected to the outside of the valve (1) and an orifice for communication with the reservoir (6) intended to be connected to the reservoir (3), the valve (1) comprising, in a body (4) provided of said four orifices (5-8), pressure-sensitive pilot means (9a-9c, 10a-10c,49) configured and arranged to be able to be moved under the effect of the pilot pressure (P1-P3) so as to adopt: - a rest position in which the pilot means ensure closure of the passages (43-45) between said orifices (5-8); - an inflation position in which said pilot means ensure communication between the orifice for communication with the reservoir (6) and the inflation-deflation orifice (7); - a deflation position in which said pilot means ensure communication between the inflation-deflation orifice (7) and the exhaust orifice (8); characterized in that said pressure-sensitive control means are also configured and arranged to adopt a tank filling position in which said control means ensure communication between the intake orifice (5) and the orifice for communication with the tank (6).,

2. Valve (1) according to claim 1, characterized in that the control means (9a-9c, 10a-10c, 49) comprise first (9a, 10a), second (9b, 10b) and third (9c, 10c) piston assemblies, each piston assembly being axially movable in a housing (46-48) in fluid communication with the inlet orifice (5) of the pilot pressure via a pilot circuit (49) successively connecting each housing (46-48) to said inlet orifice (5), the first (9a, 10a), second (9b, 10b) and third (9c, 10c) piston assemblies being sensitive, respectively, to a first (PI), second (P2) and third (P3) pilot pressure, the first pilot pressure (PI) being lower than the second pilot pressure (P2) and the second pilot pressure (P2) being lower than the third pilot pressure (P3).

3. Valve (1) according to claim 2, characterized in that the first (9a, 10a), second (9b, 10b) and third (9c, 10c) piston assemblies are configured and arranged such that, in use, when the first pilot pressure (P1) is delivered through the inlet port (5), the piston assemblies are placed in the deflation position, when the second pilot pressure (P2) is delivered through the inlet port (5), the piston assemblies are placed in the inflation position, and when the third pilot pressure (P3) is delivered through the inlet port (5), the piston assemblies are placed in the filling position, the third pilot pressure (P3) being the filling pressure of the reservoir (3).

4. Valve (1) according to any one of claims 2 and 3, characterized in that each piston assembly (9a-9c, 10a-10c) comprises a closing element (9a-9c) having a first closed axial end (90), on the pilot circuit (49) side, and a second open axial end (91) opposite, and an elastic return member (10a-10c) secured to the body (4), on the second axial end (91) side, and to the closing element (9a-9c), said elastic return member (10a-10c) being functionally associated with the closing element (9a-9c) so as to return it to the rest position, the stiffness of the elastic return member (10a) of the first piston assembly, called the first stiffness, being less than the stiffness of the elastic return member (10b) of the second piston assembly, called the second stiffness, and the second stiffness being less than the stiffness of the elastic return member (10c) of the third piston assembly,called third stiffness.,

5. Valve (1) according to claim 4, characterized in that the first, second and third stiffnesses are chosen such that the first pilot pressure (PI) is approximately 1.8 bar, the second pilot pressure (P2) is approximately 3.4 bar and the third pilot pressure (P3) is greater than or equal to 6 bar.

6. Valve (1) according to any one of claims 4 and 5, characterized in that each elastic return member (10a-10c) comprises two concentric and coaxial springs, including an outer spring (100a-100c) and an inner spring (101a-101c), the stiffnesses of the first (100a), second (100b) and third (100c) outer springs being different and the stiffnesses of the first (101a), second (101b) and third (101c) inner springs being different.

7. Valve (1) according to any one of claims 1 to 6, characterized in that the valve body (4) is a body in at least two parts comprising a housing (40) and a cover (41) detachably fixed to the housing (40) by removable fixing members (42), in particular screws.

8. Motor vehicle (V) comprising: - at least one wheel (12) comprising a tire (2) defining an interior volume, - for the or each wheel (12), a reservoir (3) capable of storing a gas under pressure, and - a remote inflation system (S) comprising a pressure source (11) carried by the vehicle (V), characterized in that the remote inflation system (S) further comprises, for the or each wheel (12), a single valve (1) according to any one of claims 1 to 7, in which valve (1) the intake orifice (5) is connected to the pressure source (11), the inflation-deflation orifice (7) is connected to the interior volume of the tire (2), the exhaust orifice (8) is connected to the outside of the valve (1) and the orifice for communication with the reservoir (6) is connected to the reservoir (3), the remote inflation system (S) further comprising a control module (14, 15) coupled to the or each valve (1) and to the pressure source (11).

9. Vehicle (V) according to claim 8, characterized in that the control module (14, 15) comprises an electropneumatic distribution box (14) connected to a control console (15).

10. Vehicle (V) according to any one of claims 8 and 9, characterized in that the remote inflation system (S) further comprises, for the or each wheel (12), a first pressure sensor (16) capable of measuring a pressure in the interior volume of the tire (2) and a second pressure sensor (17) capable of measuring a pressure in the reservoir (3).

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