VEHICLE TIRE DEVICE WITH INFLATION VALVE AND ELECTRONIC PRESSURE MONITORING MODULE

Abstract

A device for a motor vehicle tire comprising an inflation valve including an elastomer body (2) having an inner shoulder (6) that fits into the tire on a rim edge, and including an electronic pressure monitoring system module that fits into the tire and is disposed in a housing (12) formed of two half-shells assembled along a parting line. The valve includes an elastic ring (14) connected to the inner shoulder of the body (6), which receives the housing of the electronic module (12) internally to hold it in place by surrounding the parting line between its half-shells. Figure for the abbreviation: Figure 1

Description

Title of the invention: DEVICE FOR VEHICLE TIRE WITH INFLATION VALVE AND ELECTRONIC PRESSURE MONITORING MODULE Technical field

[0001] The present invention relates to a device for a vehicle tire car comprising an electronic module for a tire pressure monitoring system and an inflation valve, a wheel equipped with such a device and a method of assembling this type of wheel. Prior art

[0002] A type of known tire pressure monitoring system, "SSPP" for short, or "Tyre Pressure Monitoring System" in English, "TMPS" for short, presented in particular by document FR-A1-3084288, comprises a valve made of an elastomer comprising inside a rigid upstream tube equipped with a non-return valve allowing inflation, and a rigid downstream tube arranged in the extension of the upstream tube with a seal between the two.

[0003] In a configuration presented [Fig.5] of this document, an electronic module of a tire pressure monitoring system comprising a pressure sensor, a power supply battery and an electronic circuit comprising a radio transmitter, is fixed to the end of the downstream tube entering the rim by a screw screwed into a thread formed in the axial bore of this tube. In this way, the downstream tube of the valve is used to form a point for attaching the electronic unit inside the tire, which avoids the need to provide an independent system for attaching the unit directly to the rim.

[0004] Furthermore, the housings of the electronic pressure monitoring modules arranged inside the tires must have a high level of sealing to protect the internal components from pollution found in the tire, such as moisture introduced into the inflation air which condenses, dust present during the fitting of the tire, or grease used to facilitate the fitting of the tire in order to slide its belt over the edge of the rim, which can be corrosive.

[0005] In addition, since tire pressure monitoring systems are imposed by European standards on all four wheels in motor vehicles, it is necessary to provide low-cost modules to limit the impact on the price of complete vehicles.

[0006] To form these electronic module boxes it is known to produce two half- shells receiving the components inside, which are then assembled by an industrial mechanical system guaranteeing the seal between these two parts. In particular, a peripheral seal can be provided between the half-shells and assembly components tightening this seal such as screws or rivets. A process for sealing the housing can also be provided, for example by gluing or welding the half-shells, which guarantees both mechanical strength and seal.

[0007] However, these systems for sealing the housing are expensive, particularly with added assembly components leading to procurement and assembly costs, or by implementing a sealing process.

[0008] In addition, these electronic modules are then difficult or impossible to repair because of the difficulties of opening the case, and then closing it with a guarantee of sealing, while they contain components that can wear out, such as the power supply battery that must be changed after a period of use, or easily repairable components. The electronic module becomes a consumable product that must be thrown away at the slightest wear or failure, with few repair possibilities, which poses cost problems, and environmental problems caused by the manufacture of a new case and the necessary reprocessing of the old one. In particular, the battery, generally lithium, requires special recycling treatment that is expensive.

[0009] The present invention aims in particular to avoid these problems of the prior art. Statement of the invention

[0010] To this end, it proposes a device for a motor vehicle tire comprising an inflation valve comprising an elastomer body having an internal shoulder entering the tire on a rim edge, and comprising an electronic module for a pressure monitoring system entering the tire which is arranged in a housing formed with two half-shells assembled along a joint plane, this device being remarkable in that the valve comprises an elastic ring linked to the internal shoulder of the body, receiving inside the housing of the electronic module to hold it by surrounding the joint plane between its half-shells.

[0011] An advantage of this device is that the elastomer of the body, with a reduced cost thanks to the molding of this material, and with its elasticity, performs a function of holding the housing of the electronic module inside the tire, and moreover forms a protective contour surrounding the joint plane between the two half-shells of this housing.

[0012] We obtain a simple and economical housing to produce, with for example an em box and a quick-to-apply clip-on of the half-shells, which can then be easily opened for maintenance, repair or recycling operations. When the module is subsequently put back into service, positioning the box in the valve ring to secure it then automatically ensures that it is held and protected as originally.

[0013] The tire device according to the invention may further comprise one or more of the following characteristics, which may be combined with each other.

[0014] Advantageously, the elastic ring forms a seal around the half-shells protecting the joint plane.

[0015] Advantageously, the housing comprises an external groove surrounding its joint plane, receiving the elastic ring.

[0016] In this case, advantageously the outer groove has a hollow section in the shape of an arc of a circle.

[0017] According to one embodiment, the elastic ring has a cross section forming a circle fitting into the groove.

[0018] According to another embodiment, the elastic ring has a cross-section comprising a domed portion fitting into the outer groove, extending on each side by a lip which covers the edge of the housing beyond its outer groove.

[0019] Advantageously, the housing comprises a bore receiving the end of a rigid tube of the valve protruding into the elastic ring.

[0020] Advantageously, the two half-shells of the housing are assembled together with a connection without sealing.

[0021] Advantageously, the elastic ring is formed by the same molding with the elastomer valve body.

[0022] The invention also relates to a motor vehicle wheel comprising a tire mounted on a rim equipped with an inflation valve, remarkable in that it comprises a tire device comprising any one of the preceding characteristics, having its electronic module housing which is fixed in the elastic ring of the valve.

[0023] The invention further relates to a method of assembling a wheel comprising the preceding characteristic, remarkable in that before mounting the tire on the rim it comprises a step of inserting the valve body into a hole in the rim, and a step of fixing the housing of the electronic module in the elastic ring of the valve body. Brief description of the drawings

[0024] The invention will be better understood and other features and advantages will appear will become more clearly apparent from reading the description given below by way of example, with reference to the attached drawings in which: [Fig.l] [Fig.l] is a view of a tire device according to the invention; [Fig.2] [Fig.2] is an exploded view of this device; [Fig.3] [Fig.3] is a schematic cross-sectional view of this device at the level of the electronic module; [Fig.4] [Fig.4] is a view of a device according to a variant; [Fig.5] [Fig.5] is a view of this device with a cutaway on the elastic ring; [Fig.6] [Fig.6] is a schematic cross-sectional view of this device at the level of the electronic module. Description of the embodiments

[0025] Figures 1, 2 and 3 show a valve having an elastomer body 2 arranged along a main axis A, comprising, starting from a side outside the wheel EXT, an elongated part having a rigid axial conduit 8 receiving an air pressure for inflating the tire, an annular groove 4 provided to fit into a hole in the sheet metal of a rim, and a shoulder 6 bearing on the inner side of this sheet metal. The rigid conduit 8 is extended by an inner end 10 extending beyond the shoulder 6, to supply air to the tire.

[0026] A closed elastic ring 14 made in the same molding as the elastomer of the body 2, has a circular contour which is arranged in an axial plane of the valve. The elastic ring 14 has a round cross-section which is constant, the inner end 10 of the rigid conduit 8 opening inside this ring.

[0027] An electronic module for a tire pressure monitoring system comprises a housing 12 comprising a lower half-shell 20 and an upper half-shell 22 made by molding plastic material, forming after assembly a substantially square housing of small thickness. The housing 12 comprises inside an electronic circuit board 24 wedged in this housing, receiving welded components comprising a pressure sensor, a radio transmitter, and below a lithium electric battery 26 welded on this plate.

[0028] The half-shells 20, 22 of the housing 12 are fitted to one another along a flat joint plane arranged in the thickness of the housing, internal tabs 28 ensuring their relative positioning. The closed housing 12 has on its contour an external groove 30 having a constant hollow cross-section forming a semicircle, which is centered on the joint plane.

[0029] In the assembly position shown [Fig.l], the housing 12 is inserted into the elastic ring 14 by stretching and deforming this ring to fit it into the outer groove 30 having a complementary shape, so as to enter therein half of its section. The hollow section of the groove 30 receiving the elastic ring 14 tightened inside, ensures the maintenance of the housing 12.

[0030] With sufficient tightening of the elastomer due to its extension to bypass the housing 12, a pressure of the ring 14 is obtained which is applied to the surface of the two parts of the groove 30 formed by the two half-shells 20, 22, ensuring a seal on these two parts which protects the joint plane.

[0031] The upper half-shell 22 has on one side a bore 32 opening out on the other side, without entering the interior of this housing, receiving in an adjusted manner the end 10 of the rigid conduit 8 of the valve so as to form a positioning of the housing on this valve, and a support complement which is added to that of the elastic ring 14.

[0032] By inserting the end 10 of the rigid conduit 8 into the bore 32 of the already assembled housing 12, then by adjusting this housing in the elastic ring 14 with an elongation of this ring, a simple and rapid assembly is obtained, not using any additional fixing component, which ensures both the holding of the housing in the tire and the sealing between its two half-shells 20, 22.

[0033] Furthermore, for maintenance or repair operations, the electronic module is removed simply, without tools, by removing the housing 12 from the elastic ring 14 by deforming it. The housing 12, which has been closed without gluing or welding, for example by removing closing clips, can then be opened cleanly and quickly to carry out operations inside, then closed by operating in reverse. The seal between the half-shells 20, 22 will be reestablished by reassembling the housing 12 in the elastic ring 14 of the valve fixed on the rim, with a quality identical to that of the original.

[0034] Figures 4, 5 and 6 show as a variant an elastomer valve body comprising inside the tire the elastic ring 14 having a constant cross section having a curved part following an arc of a circle 42 facing the inside of the ring which fits into the outer groove 30 of the housing 12, and on each side of a lip 44 which rises on the rounded edge of the bottom or top of this housing. In this configuration, it can be envisaged to do without the drilling 32 and the end 10 of the rigid conduit 8 of the valve, the positioning and the holding of the housing on this valve, then being carried out solely by means of the elastic element 14.

[0035] The outer end of the valve is shown with its protective cap 40 which closes the inflation orifice.

[0036] In a similar manner, support is obtained from the inner curved part of the section of the elastic ring 14 which presses both on the two half-shells 20, 22, and each side a lip which presses on the rounded edges of these half-shells to cover them, in order to ensure greater watertightness.

[0037] In this way, the contours of the housing 12 are also protected by the elastomer, which can protect them from possible impacts, particularly when fitting the tire.

Claims

Claims

1. Device for a motor vehicle tire comprising an inflation valve comprising an elastomer body (2) having an inner shoulder (6) entering the tire on a rim edge, and comprising an electronic module for a pressure monitoring system entering the tire which is arranged in a housing (12) formed with two half-shells (20, 22) assembled along a joint plane, characterized in that the valve comprises an elastic ring (14) linked to the inner shoulder of the body (6), receiving inside the housing of the electronic module (12) to hold it by surrounding the joint plane between its half-shells (20, 22).

2. A tire device according to claim 1, characterized in that the elastic ring (14) forms a seal around the half-shells (20, 22) protecting the joint plane.

3. A tire device according to claim 2, characterized in that the housing (12) has an external groove (30) surrounding its joint plane, receiving the elastic ring (14).

4. A tire device according to claim 3, characterized in that the outer groove (30) has a hollow section in the shape of an arc of a circle.

5. A tire device according to claim 3 or 4, characterized in that the elastic ring (14) has a cross-section forming a circle fitting into the groove (30).

6. A tire device according to claim 3 or 4, characterized in that the elastic ring (14) has a cross-section comprising a domed portion fitting into the outer groove (30), extending on each side by a lip (44) which covers the edge of the housing (12) beyond its outer groove (30).

7. A tire device according to any one of the preceding claims, characterized in that the housing (12) comprises a bore (32) receiving the end (10) of a rigid tube (8) of the valve protruding into the elastic ring (14).

8. A tire device according to any one of the preceding claims, characterized in that the two half-shells of the housing (20, 22) are assembled together with a non-sealing connection.

9. A tire device according to any one of the preceding claims, characterized in that the elastic ring (14) is formed by the same molding with the elastomer valve body (2).

10. Motor vehicle wheel comprising a tire mounted on a rim equipped with an inflation valve, characterized in that it comprises a tire device according to any one of the preceding claims, having its electronic module housing (12) which is fixed in the elastic ring of the valve (14).

11. Method of assembling a wheel according to claim 10, characterized in that before mounting the tire on the rim it comprises a step of inserting the valve body (2) into a hole in the rim, and a step of fixing the housing of the electronic module (12) in the elastic ring of the valve body (14).

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