JP2000203222A - Tire pneumatic information transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and surely output a radio wave relating to tire pneumatic information. SOLUTION: A valve system 28 is mounted on a wheel 26 via a grommet 42, and a transmitter body 30 is integrated with the valve system 28. An earth metal 68 coated with a rubber coating layer 76 is interposed in a gap 66 between a bottom part 50A of a case 50 of the body 30 and a rim 26A. A portion for covering a protrusion 74 in the rubber coating layer 76 is broken by the protrusion 74 when the valve system 28 is assembled. The wheel 26 itself is made thereby to act as a gland of the valve system 28 used as an antenna, and the earth metal 68 is prevented from rusting. A radio wave as to tire pneumatic information is output efficiently and surely as a result thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tire pressure information transmitting apparatus using a valve system for injecting air as an antenna.

[0002]

2. Description of the Related Art Hitherto, there have been proposed several tire pressure information transmitting apparatuses for promptly recognizing a driver that a tire pressure is decreasing. For example, a transmitter is installed in a tire to transmit radio waves with an antenna on a circuit board and GND, or a valve system for injecting air is used as an antenna,
An antenna and the like that transmit a radio wave by using the antenna and GND on a circuit board have been proposed.

[0003] By the way, the current steel radial tire has a structure in which only the tire contact surface is reinforced with a belt using a steel wire. In the future, a steel radial tire in which the sidewall is reinforced with steel will be used. May be used. In the case where such a tire is assumed, if a conventional tire pressure information transmitting device is used, the output radio wave may be shielded by the steel of the tire, and the radiation of the radio wave to the outside of the tire may be hindered.

The present invention has been made in view of the above background, and an object of the present invention is to provide a tire pressure information transmitting apparatus capable of efficiently and reliably outputting radio waves relating to tire pressure information.

[0005]

According to the present invention, there is provided a tire pressure information transmitting apparatus according to the present invention, which is mounted on a rim of a wheel so as to protrude toward the outside of the tire via an insulator. A valve system, a transmitter body that is provided integrally with the valve system, and transmits tire pressure information as radio waves by using the valve system as an antenna, and is interposed in a gap between the transmitter body and a rim of a wheel. And a grounding metal which is electrically connected to the transmitter body and has a projection which is in contact with the rim of the wheel when the valve system is mounted on the rim of the wheel. Cover the surface of the part to be mounted, and use the protrusion of the grounding bracket when mounting the valve system on the rim of the wheel. It is characterized in that the portion of covering the tip portion and a, a coating layer is broken.

According to the first aspect of the present invention, a valve system for injecting air is mounted on the rim of the wheel so as to protrude toward the outside of the tire via an insulator. A transmitter body is provided integrally. Then, by using the valve system as an antenna, the tire pressure information is transmitted as radio waves from the transmitter body.

Here, in the present invention, a grounding metal which is electrically connected to the transmitter main body is interposed in a gap between the transmitter main body and the rim of the wheel, and the valve system is mounted on the rim of the wheel. Since the projection of the metal fitting is made to contact the rim of the wheel, the wheel itself acts as a ground for the antenna (ie, the valve system). Therefore, the lines of electric force radiated from the antenna reach the wheel without fail. That is, it is possible to output a radio wave relating to the tire pressure information without being affected by the tire side.

Further, according to the present invention, the surface of a portion existing in the gap in the earth metal fitting is covered with a coating layer made of an insulating material, and when the valve system is mounted on the rim of the wheel, the tip of the projection is formed by the projection of the earth metal fitting. Since the covering portion is broken, the surface of the grounding metal can be prevented from rusting, and the electrical contact between the projection of the grounding metal and the rim of the wheel can be maintained well.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A tire pressure monitoring system 10 according to the present invention will be described below with reference to FIGS.

FIGS. 6 and 7 are system configuration diagrams of a tire pressure monitoring system 10 according to the present embodiment. As shown in these figures, the tire pressure monitoring system 10 is provided on each of the front wheel 12 and the rear wheel 14 and includes information on the air pressure, internal temperature, and the like of the tire 16 (hereinafter, these information are collectively referred to as “ Tire pressure information "
) As a radio wave, a tire pressure information receiver (receiver) 22 installed at a predetermined portion of the vehicle 20 and receiving a radio wave transmitted from each tire pressure information transmitter 18. And a monitor 24 installed on a meter or the like to display tire pressure information to inform a driver based on radio waves received by the tire pressure information receiving device 22.

FIG. 1 shows a longitudinal sectional structure of the tire pressure information transmitting device 18 described above. As shown in the figure, the tire pressure information transmitting device 18 includes a valve system 28 disposed on a rim 26A of the wheel 26,
A transmitter main body 30 provided integrally with the valve system 28 is configured as a main part.

First, the configuration of the valve system 28 will be described. As shown in FIGS. 1 and 2, the wheels such as the front wheel 12 and the rear wheel 14 include a wheel 26 and a tire 16 mounted on an outer peripheral portion of a rim 26 </ b> A of the wheel 26. The wheel 26 is made of a metal material such as steel or an aluminum alloy, and the tire 16 is made of a composite of a metal material such as steel such as a carcass 32, a bead 34, a belt 36, and a tread 38 or a rubber material. In the tire 16, a reinforcing belt 36 made of a metal material such as steel is also provided in the sidewall 39.

At a predetermined position on the outer peripheral portion of the rim 26A of the wheel 26, an insertion hole 40 having a predetermined diameter is formed, and a pair of "insulators" made of rubber, resin, or the like is formed in the insertion hole 40. Grommet 42 is mounted. The grommet 42 includes a flange portion 42A having a larger diameter than the insertion hole 40, and a cylindrical extension portion 42B extending in the axial direction from the axis of the flange portion 42A. The extension 42B of the grommet 42
Is set to １ ／ of the plate thickness of the rim 26A.

A valve system 28 for injecting air is attached to the rim 26A of the wheel 26 via the grommet 42. More specifically, the valve body 44 is inserted into the extension 42B of the pair of grommets 42 from the inside of the tire. The valve body 44 is formed in a substantially disc shape with a step, and the flange portion 4 of the grommet 42 is formed.
The flange 44A is made up of a flange 44A that comes into contact with the flange 2A, and a substantially cylindrical shaft 44B that stands upright from the shaft core of the flange 44A and is inserted into the extension 42B of the grommet 42. The shaft core of the shaft 44B includes a tire valve core 46.
Are provided in a screwed state. A male screw is formed on the outer peripheral surface on the distal end side of the shaft portion 44B, and the nut 48 is screwed onto the male screw, whereby the valve body 44 is fixed to the rim 26A via the grommet 42.

When the valve system 28 is attached to the rim 26A of the wheel 26 via the grommet 42 as described above, the shaft portion 44B of the valve body 44 projects toward the outside of the tire (see FIG. 2). ).

Next, the configuration of the transmitter body 30 will be described. As shown in FIG. 1, the transmitter main body 30 has a substantially box-shaped case 5 made of an insulating material such as resin.
0 and a flat lid 52 which is also made of an insulating material such as a resin and closes the open end of the case 50, constitutes an outer shell thereof. The bottom 50A of the case 50 is insert-molded in the flange 44A of the valve body 44, whereby the transmitter body 30 is provided integrally with the valve system 28.

A circuit board 54 is accommodated in the internal space defined by the case 50 and the lid 52. A sensor 56, a wireless oscillator 58, a control unit (microcomputer) 60, a battery 62, and the like are incorporated in the circuit board 54.

The sensor 56 is connected to the battery 62 and the control unit 60, detects tire pressure and internal temperature, converts the detection result into an electric signal, and outputs the signal to the control unit 60. The type of the sensor 56 is appropriately selected according to the detection item, and here, a pressure sensor, a temperature sensor, or the like is used. The control unit 60 is connected to the battery 62 and the wireless oscillator 58, and based on the detection result of the sensor 56, transmits the current tire pressure information to the wireless oscillator 58.
Output. Further, the wireless oscillator 58
Is connected to the power supply line 64 extending from the control unit 60 and the flange 44A of the valve body 44, and based on the electric signal output from the control unit 60, the current tire pressure information is transmitted to the valve body 44. Is transmitted as an antenna.

An earth metal fitting 68 is interposed in the gap 66 between the bottom 50A of the case 50 of the transmitter body 30 and the rim 26A of the wheel 26, and will be described in detail below. As shown in FIG. 1 and FIGS. 3 to 5, the grounding metal fitting 68 includes a metal fitting body 70 formed in a rectangular frame shape, and metal fitting legs integrally extending from an arbitrary corner of the metal fitting body 70. 72 and conical projections 74 protruding from the four corner surfaces of the metal fitting body 70, respectively. Further, the metal fitting body 70 and the four projections 74 of the ground metal fitting 68 are provided with a rubber coating layer 7 as a “coating layer”.
6.

The metal foot 72 of the ground metal 68 is
It is connected to the battery 62 side of the circuit board 54 through the bottom 50A of the case 50. Further, in a state where the earth metal fitting 68 is mounted between the bottom 50A of the case 50 and the rim 26A of the wheel 26, the four protrusions 74 of the earth metal fitting 68 break the rubber coating layer 76 and the outer peripheral surface of the rim 26A (tire) 5 (contact side).
reference).

Next, the procedure for assembling the tire pressure information transmitting device 18 according to the present embodiment will be described, and the operation and effects of the present embodiment will be described through the description.

The flange 44A of the valve body 44 of the valve system 28 and the case 50 of the transmitter body 30 are previously integrated by insert molding. The circuit board 54 is mounted in the case 50, and the earth metal fitting 68 is arranged on the bottom 50 </ b> A side of the case 50, and the metal fitting leg 72 is inserted into the case 50. After that, the power supply line 64 and the wireless oscillator 5
8 and the metal foot 72 are connected to the battery 62 side, and then the lid 52 is closed. Thus, the tire pressure information transmitting device 18 is sub-assembled. In this state, the metal fitting body 70 of the ground metal fitting 68 and the four projections 74
Are in a state of being covered by the rubber coating layer 76.

Next, a pair of grommets 42 are fitted into the insertion holes 40 of the rim 26A of the wheel 26, and the shaft portions 44B of the valve body 44 are inserted into the extended portions 42B of these grommets 42 from inside the tire. . Next, a nut 48 is screwed into the distal end of the shaft portion 44B penetrating the grommet 42. As the tightening of the nut 48 progresses,
Four protrusions 7 of a ground metal fitting 68 interposed in a gap 66 between the bottom 50A of the case 50 and the rim 26A of the wheel 26
4 gradually contacts and bites into the rim 26A of the wheel 26. At this time, the rubber coating layer 76 covering the projection 74 is broken, and the tip of the projection 74 comes into direct contact (piercing) with the rim 26A.

When the assembling work of the tire pressure information transmitting device 18 has been completed as described above, the grounding metal fitting 68 and the wheel 26 are connected, and an antenna system is formed outside the tire.

The tire pressure information such as the pressure and the internal temperature of the tire 16 when the vehicle is running is detected by a sensor 56. The tire pressure information detected by the sensor 56 is converted into an electric signal and is constantly output to the control unit 60. The controller 60 processes the electric signal output from the sensor 56 and outputs the current tire pressure information to the wireless oscillator 58. From the control unit 60 to the wireless oscillator 5
When the tire pressure information is output to 8, the current tire pressure information is transmitted as a radio wave by using the shaft portion 44 </ b> B of the valve body 44 as an antenna. The transmitted radio wave relating to the tire pressure information is transmitted to a tire pressure information receiving device (receiver) 22 mounted on the vehicle.
Monitor 24 to inform the driver
Will be displayed.

Here, in the present embodiment, the transmitter body 30
A grounding metal 68 electrically connected to the battery 62 side of the circuit board 54 of the transmitter body 30 is interposed in a gap 66 between the rim 26A of the wheel 26 and the rim 26A of the wheel 26. By performing the attaching operation, the protrusion 74 of the grounding metal fitting 68 is brought into contact with the rim 26A of the wheel 26, so that the wheel 26 itself acts as a ground for the antenna (that is, the valve system 28). For this reason, the electric lines of force P radiated from the shaft portion 44B of the valve body 44 of the valve system 28
(See FIG. 2) reaches the wheel 26 reliably. That is, a radio wave relating to tire pressure information can be output without being affected by the tire 16 side. As a result, according to the present embodiment, it is possible to efficiently output radio waves related to tire pressure information.

Further, in this embodiment, the grounding metal 68
Is covered with a rubber coating layer 76 made of an insulating material, and the tip of the projection 74 is covered by the projection 74 of the grounding metal fitting 68 when the valve system 28 is mounted on the rim 26A of the wheel 26. , The surface of the grounding member 68 can be prevented from rusting, and the electrical contact between the projection 74 of the grounding member 68 and the rim 26A of the wheel 26 can be maintained well. Can be. More specifically, the valve body 44 of the valve system 28
Is also a portion that is in contact with water that has entered during rainfall, car washing, and the like. Further, the earth metal fitting 68 is exposed to sulfur emitted from the tire 16. Since the earth metal fitting 68 is placed in such an environment, if no surface treatment is performed, the earth metal fitting 68 is very likely to rust and may not be able to maintain electrical contact with the wheel 26. However, if the earth metal fitting 68 is covered with the rubber coating layer 76 as in the present embodiment, the generation of rust can be reliably prevented. as a result,
According to the present embodiment, it is possible to reliably output a radio wave relating to tire pressure information.

In addition, the earth fitting 6 in the present embodiment
The metal fitting body 70 of No. 8 is formed in a rectangular frame shape, and the projections 74 are provided at the four corners of the metal fitting body 70, so that the assembly state can be stabilized.

In this embodiment, since the grommet 42 is used as an insulator for mounting the valve body 44,
By controlling the thickness of the flange portion 42A of the grommet 42, the dimension of the gap 66 can be controlled. Therefore, it is possible to easily manage the condition that the coating layer 76 is broken by the tip of the projection 74 when the valve system 18 is assembled.

In this embodiment, the power supply line 64 corresponding to the radio wave output terminal is formed integrally with the flange 44A of the valve body 44 and connected to the radio oscillator 58.
However, the present invention is not limited to this, and the power supply line 64 may be connected to the wireless oscillator 58 in advance and attached to the flange 44A of the valve body 44 later.

In this embodiment, the metal fitting leg 72 corresponding to the GND terminal is integrally formed at an arbitrary corner of the ground metal fitting 68. However, the present invention is not limited to this. For example, a screw structure or the like is adopted. By doing so, the metal fitting body 70 of the ground metal fitting 68 and the battery 62 side of the circuit board 54 may be connected later.

Further, in this embodiment, the grounding metal 68
Is constituted by a rectangular frame-shaped metal fitting body 70, projections 74 provided at the four corners of the metal fitting body 70, and metal fitting legs 72 extending from arbitrary corners, but the shape of the earth metal fitting is arbitrarily changed in design. Therefore, the shape and the like are not limited to this, and various shapes can be adopted. For example, if the stability of the assembled state is ensured by a separate member (spacer or the like), a bar-shaped metal body can be used instead of the rectangular frame-shaped metal body 70.

In the present embodiment, the metal fitting body 70 and the four projections 74 are covered with the rubber coating layer 76. However, the present invention is not limited to this. Any material that can be broken by the projection 74 at any time can be used. In that sense, the category of the “coating layer” includes the rubber coating layer 7.
Not only 6, but also a resin coating layer and a coating layer are included.

Further, in the present embodiment, the grommet 42 is used as the "insulator". However, the present invention is not limited to this, and an O-ring or the like may be used.

In the present embodiment, the tire pressure and the like are always detected by the sensor 56. However, the present invention is not limited to this. When the tire pressure or the like falls below a certain reference value (or rises above). Alternatively, a sensor that outputs a detection signal to the control unit 60 may be used.

[0036]

As described above, in the tire pressure information transmitting apparatus according to the first aspect of the present invention, a transmitter body is integrally provided in a valve system mounted on a rim of a wheel via an insulator. In the configuration in which the tire pressure information is transmitted as radio waves by using the valve system as an antenna, a ground metal is interposed in a gap between the transmitter body and the rim of the wheel, and the valve system is mounted on the rim of the wheel. The protrusion of the grounding fitting is brought into contact with the rim of the rim, so that the wheel itself acts as a ground for the valve system as an antenna, and as a result, an excellent effect that radio waves relating to tire pressure information can be efficiently output. Having.

Further, in the tire pressure information transmitting apparatus according to the present invention, a transmitter body is integrally provided in a valve system mounted on a rim of a wheel via an insulator, and the valve system is connected to an antenna. In the configuration in which the tire pressure information is transmitted as radio waves by using as, the surface of the grounding metal is covered with a coating layer, and when the valve system is mounted on the rim of the wheel, the coating layer is broken by the projection of the grounding metal. Therefore, it is possible to prevent the surface of the grounding metal from rusting, and as a result, there is an excellent effect that radio waves relating to tire pressure information can be reliably output.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a tire pressure information transmitting device which is a main part of a tire pressure monitoring system according to an embodiment.

FIG. 2 is an explanatory diagram for explaining an operation when the tire pressure information transmitting device shown in FIG. 1 is used.

FIG. 3 is a perspective view of the rubber-coated ground metal shown in FIG. 1;

FIG. 4 is a longitudinal sectional view of the grounding metal shown in FIG. 3;

FIG. 5 is an enlarged sectional view showing a state where the rubber coating layer is broken by a protrusion of a grounding member during assembly and the protrusion comes into contact with a rim of a wheel.

FIG. 6 is a system configuration diagram of a tire pressure monitoring system according to the present embodiment.

FIG. 7 is a system configuration diagram of a tire pressure monitoring system according to the embodiment, similarly to FIG. 6;

[Explanation of symbols]

 Reference Signs List 16 tire 18 tire pressure information transmitting device 26 wheel 26A rim 28 valve system 30 transmitter main body 42 grommet (insulator) 66 gap 68 grounding metal fitting 74 projection 76 coating layer (coating layer)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junzo Oe 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Michiya Kato 100 Kutoku Town, Ogaki City, Gifu Prefecture Pacific Industrial Co., Ltd. F Terms (reference) 2F055 AA12 BB19 CC60 DD20 EE40 FF38 GG03 GG25 HH03 HH06 HH19

Claims (1)

[Claims] 1. A valve system for air injection which is mounted on a rim of a wheel so as to protrude toward the outside of a tire via an insulator, and is provided integrally with the valve system, and the valve system is used as an antenna. A transmitter body for transmitting tire pressure information as radio waves by using the transmitter body; a transmitter system that is interposed in a gap between the transmitter body and a wheel rim and is electrically connected to the transmitter body; A metal fitting having a projection that comes into contact with the rim of the wheel by being attached to the rim of the wheel. A coating layer in which a portion covering the tip of the projection is broken by the projection. Tire air pressure information transmission apparatus that.