JP2007112163A - Wheel sensor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire sensor unit to detect quantity of state of a tire while restraining unbalance of weight in the circumferential direction of the wheel and restraining increase of cost of the wheel and increase of the weight of the wheel. <P>SOLUTION: A battery 20 and constitutional elements except for the battery 20 constituting this wheel sensor device 50 constituting the wheel sensor device 50 are arranged on the wheel 10 as they are respectively distributed on radial lines opened at an angle of roughly 180° in the circumferential direction of the wheel 10 on the wheel sensor device 50 to detect the quantity of state of the wheel 10. The battery 20 is arranged on a surface of a wheel rim 14 facing the outside of the vehicle. A pneumatic pressure sensor 24 to detect pneumatic pressure of the tire, a strain gage 18 to detect deformation of the tire and force given to the tire and a radio transmitter 22 to transmit the detected quantity of state of the wheel 10 to the car body by radio are included in the constitutional elements except for the battery 20. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wheel sensor device, and more particularly to a wheel sensor device that detects a state quantity of a wheel.

In recent years, in order to realize safer driving of a vehicle, as described in Patent Document 1, for example, a tire pressure monitoring system (TPMS) that transmits information such as tire air pressure to a vehicle body wirelessly and notifies a driver. Development of technology to install tire pressure monitoring systems on vehicles is underway. When such a tire pressure monitoring system is provided in a vehicle, it is necessary to provide a wheel sensor device for detecting the tire air pressure on the wheel. However, if the wheel sensor device is mounted at a predetermined position on the wheel, there is a risk of unbalanced weight in the circumferential direction of the wheel. Such unbalanced weight may be caused by vibration of the wheel during wheel rotation. May lead to For this reason, for example, Patent Document 2 proposes a tire air pressure alarm device in which a balance weight substantially corresponding to the weight of a sensor unit such as a pressure sensor is provided on a disc wheel. Moreover, since the battery which supplies electric power to a sensor or a transmitter is generally provided in the tire chamber, it is difficult to replace the battery. For this reason, for example, Patent Document 3 proposes a tire pressure alarm device in which a pressure detecting element is fixed to the inside of a wheel rim portion and a radio wave transmitter or the like is attached to a wheel cap.
JP 11-254926 A Japanese Patent Laid-Open No. 5-104919 JP 11-32254 A

  However, in the tire air pressure alarm device described in Patent Document 2 described above, a balance weight substantially corresponding to the weight of the sensor unit must be prepared, and it is difficult to reduce costs and vehicle weight. Moreover, in the tire air pressure alarm device described in Patent Literature 1 and Patent Literature 3 described above, it is difficult to suppress the weight imbalance in the circumferential direction of the wheel.

  The present invention has been made in view of these problems, and its object is to suppress weight imbalance in the circumferential direction of the wheel, and to suppress an increase in the cost of the wheel and an increase in the weight of the wheel. However, the tire sensor unit for detecting the state quantity of the tire is provided on the wheel.

  In order to solve the above-described problems, a wheel sensor device according to an aspect of the present invention includes a detection unit that detects a state of a wheel, a transmission unit that transmits detected wheel state information to a vehicle body, and a detection unit or a transmission unit. In the wheel sensor device including at least a battery for supplying electric power as a component, the components constituting the wheel sensor device are divided into a plurality of groups, and the plurality of groups are distributed in the circumferential direction of the wheel and arranged on the wheels. . According to this aspect, since the imbalance of the weight in the circumferential direction of the wheel can be suppressed using the components constituting the wheel sensor device, the balance weight increases the cost of the wheel and increases the weight of the wheel. It can be suppressed.

  The wheel sensor device according to the present embodiment disperses a plurality of groups in the wheel circumferential direction and arranges them on the wheel so that the center of gravity of the wheel sensor device is located at the approximate center of the wheel. According to this aspect, the wheel sensor device can suppress the weight in the circumferential direction of the wheel from becoming unbalanced.

  The wheel sensor device according to this embodiment disperses a plurality of groups on the radiation that is opened at an angle of about 180 ° in the circumferential direction of the wheel and arranges the groups on the wheel. According to this aspect, it is possible to easily suppress the weight imbalance in the circumferential direction of the wheel by dispersing the plurality of divided groups in two places and arranging them on the wheel.

  One group of the plurality of groups may be constituted by a battery. According to this aspect, the battery having a large weight and the components other than the battery are each divided into groups and distributed to two places and arranged on the wheel, so that it is easy to unbalance the weight in the circumferential direction of the wheel. Can be suppressed.

  The battery may be arranged in the vehicle outer direction from the wheel rim surface facing the vehicle outer side. According to this aspect, the battery can be easily accessed from the outside of the vehicle.

  The detection means may be an air pressure sensor that is provided in the tire chamber and detects the air pressure of the tire. According to this aspect, in the case where the wheel sensor device that detects the tire air pressure is attached to the wheel, it is possible to suppress weight imbalance in the circumferential direction of the wheel.

  The detection means may be a strain gauge that is provided on the rubber layer or the tire inner surface of the tire and detects deformation of the tire or force applied to the tire. According to this aspect, when the wheel sensor device that detects the deformation of the tire or the force applied to the tire is attached to the wheel, it is possible to suppress the weight imbalance in the circumferential direction of the wheel.

  According to the wheel sensor device of the present invention, a tire sensor unit that detects a state quantity of a tire while suppressing an imbalance of the weight in the circumferential direction of the wheel and suppressing an increase in cost and an increase in weight. Can be provided on the wheel.

  Hereinafter, embodiments of the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings.

  FIG. 1 is a front view of a wheel 10 on which a wheel sensor device 50 according to the present embodiment is mounted. The wheel 10 includes a tire 12, a wheel rim 14, a wheel sensor device 50, and the like.

  The wheel rim 14 is formed in a cylindrical shape from a metal material such as aluminum or iron. A flange portion projecting radially outward is provided at an end portion of the wheel rim 14. The tire 12 is mounted on the outer periphery of the wheel rim 14, and movement of the wheel 10 in the axial direction is restricted by the flange portion.

  The wheel sensor device 50 includes a plurality of components such as a wheel sensor unit 16, a strain gauge 18, and a battery 20. Furthermore, the wheel sensor unit 16 includes components such as a wireless transmitter 22, a pneumatic sensor 24, and a valve 26.

  The wireless transmitter 22 and the air pressure sensor 24 are integrally formed with the valve 26. The valve 26 is formed in a shaft shape, and a male screw is formed on the outer periphery. An insertion hole through which the valve 26 is inserted is provided in the vicinity of the flange portion on the vehicle outer side of the wheel rim 14. The valve 26 is inserted into the insertion hole from the periphery of the wheel rim 14 where the valve 26 becomes the air chamber of the tire 12 toward the outside of the vehicle, and a nut is fastened to the valve 26, whereby the wireless transmitter 22 and the air pressure sensor 24. , And components such as a valve 26 are secured to the wheel rim 14. Thus, the radio transmitter 22 and the air pressure sensor 24 are arranged in the air chamber of the tire 12 with the wheel rim 14 interposed therebetween, and the valve 26 is arranged outside.

  The air pressure sensor 24 detects the air pressure in the air chamber of the tire 12. Therefore, the air pressure sensor 24 functions as a detection unit that detects the state quantity of the wheel 10. The air pressure sensor 24 is connected to the wireless transmitter 22, and the detection result of the air pressure sensor 24 is input to the wireless transmitter 22. The wireless transmitter 22 wirelessly transmits the detection result of the air pressure sensor 24 to a receiver (not shown) provided on the vehicle body. For this reason, the wireless transmitter 22 functions as a transmission unit that transmits the detected state information of the wheel 10 to the vehicle body. The receiver is connected to an electronic control unit (not shown) (hereinafter referred to as “ECU”) provided on the vehicle body, and the received detection result of the air pressure sensor 24 is input to the ECU. The ECU uses the detection result of the air pressure sensor 24 to determine whether the air pressure in the air chamber of the tire 12 is equal to or lower than a predetermined air pressure at predetermined time intervals. When it is determined that the air pressure in the air chamber of the tire 12 is equal to or lower than the predetermined air pressure, the ECU notifies the driver that the air pressure in the tire 12 has decreased on a display provided in the vehicle interior. Warning. Thus, the tire pressure alarm device is configured by the wheel sensor device 50, the receiver, the ECU, the display, and the like.

  The strain gauge 18 is provided in the rubber layer of the tire 12 and detects deformation of the tire 12 and a force applied to the tire 12. Therefore, the strain gauge 18 functions as detection means for detecting the state quantity of the wheel 10. The strain gauge 18 may be provided on the inner surface of the tire 12. The strain gauge 18 is connected to the wireless transmitter 22, and the received detection result of the strain gauge 18 is input to the wireless transmitter 22. The wireless transmitter 22 wirelessly transmits the detection result of the strain gauge 18 to a receiver provided on the vehicle body, and the receiver inputs the received detection result of the strain gauge 18 to the ECU. The ECU uses the detection result of the strain gauge 18 for various controls such as vehicle attitude control.

  In this embodiment, the component which comprises the wheel sensor apparatus 50 which detects the state quantity of the wheel 10 is divided | segmented into two groups, the wheel sensor unit 16, the strain gauge 18, and the battery 20. FIG. The wheel sensor unit 16, the strain gauge 18, and the battery 20 that are divided as a group are distributed in the circumferential direction of the wheel 10 around the central axis of the wheel 10 and arranged on the wheel 10. More specifically, the battery 20, the wheel sensor unit 16 and the strain gauge 18 as a group other than the battery 20 are arranged on the radiation opened at an angle of about 180 ° in the circumferential direction of the wheel 10 around the central axis of the wheel 10. Are distributed on the wheel 10.

  In this way, the constituent elements of the wheel sensor device 50 are divided into a plurality of groups, and the divided groups are distributed and arranged in the circumferential direction of the wheel 10, thereby using the constituent elements of the wheel sensor device 50. The imbalance of the weight in the circumferential direction of the wheel 10 can be suppressed, and the increase in the cost of the wheel 10 and the increase in the weight of the wheel 10 due to the balance weight can be suppressed. Further, by disposing the components of the wheel 10 on the radiation opened at an angle of about 180 ° in the circumferential direction of the wheel 10, the complexity of wiring associated with distributing the components at a plurality of locations, etc. And the imbalance of the weight in the circumferential direction of the wheel 10 can be easily suppressed.

  Therefore, the battery 20 constituting the wheel sensor device 50 and the wireless transmitter 22, the air pressure sensor 24, and the strain gauge 18 as constituent elements included in a group other than the battery 20 are dispersed in the circumferential direction of the wheel 10. 10 is arranged. For this reason, the battery 20 is connected to the wireless transmitter 22, the air pressure sensor 24, and the strain gauge 18 via conductive wires 34 incorporated in the wheel rim 14, and these components are connected via the conductive wires 34. To supply power. The battery 20 is disposed on the surface of the wheel rim 14 and is fixed to the wheel rim 14.

  Among the components constituting the wheel sensor device 50, the battery 20 is relatively heavy. As described above, by disposing the battery 20 and the components other than the battery 20 in two locations, respectively, and disposing the components on the wheel 10, weight imbalance in the circumferential direction of the wheel 10 can be easily suppressed.

  FIG. 2 is a cross-sectional view of the wheel 10 on which the wheel sensor device 50 according to this embodiment is mounted.

  A concave portion recessed inwardly of the diameter is formed at a substantially axial center of the wheel rim 14. The wireless transmitter 22 and the air pressure sensor 24 are arranged so as to be accommodated in the recess formed in the wheel rim 14 as described above, and are fixed to the wheel rim 14 by sandwiching the wheel rim 14 together with the valve 26.

  The strain gauge 18 is embedded in the tread portion 12 a in the rubber layer of the tire 12. By disposing the strain gauge 18 in the tread portion 12a as a portion where the tire 12 is installed on the road surface, it is possible to detect a force applied to the tire 12 when the vehicle travels or turns.

  The battery 20 has a main body portion 20a and a clip portion 20b in which electric power is stored. The clip portion 20b is formed in a U shape by an elastic material such as metal or resin. The main body portion 20a and the clip portion 20b are integrally coupled. When the clip portion 20b is fitted into the flange portion of the wheel rim 14, the battery 20 is fixed on the wheel rim outer surface 14a facing the vehicle outer side. Thus, the battery 20 is arranged in the vehicle outer direction from the wheel rim outer surface 14a, so that the user can easily access the battery 20 from the outer side of the vehicle and can easily replace the battery 20. It becomes.

  A conductive wire 34 is embedded over the half circumference of the wheel rim 14 at the base portion of the flange portion outside the vehicle of the wheel rim 14. The conductive wire 34 is provided with a wheel rim first contact 30 exposed on a radially outer surface of the wheel rim 14 at the upper portion of the valve 26. Further, the wheel rim 14 is exposed on the outer surface in the radial direction at a position rotated about 180 ° in the circumferential direction around the central axis of the wheel rim 14 with respect to the wheel rim first contact 30 at the upper part of the valve 26. A wheel rim second contact 31 is provided.

  The chafer 12b of the tire 12 is provided with a tire contact 32 exposed on the side in contact with the outer peripheral surface of the wheel rim 14. The tire contact 32 and the strain gauge 18 are connected by a conductive wire 28 embedded in the rubber layer of the tire 12. When the tire 12 is fitted into the wheel rim 14, the tire contact 32 and the wheel rim first contact 30 can be brought into contact with each other. At this time, the relative positional relationship between the tire 12 and the wheel rim 14 in the circumferential direction is restricted to the tire 12 or the wheel rim 14 so that the tire contact 32 and the wheel rim first contact 30 can be easily contacted. A guide may be provided. Moreover, the mark etc. which show the relative attachment position of the circumferential direction of the tire 12 and the wheel rim 14 may be provided in the tire 12 or the wheel rim 14. The wheel rim first contact 30 is also connected to the wireless transmitter 22 and the air pressure sensor 24 via a conductive wire embedded in the wheel rim 14.

  A battery contact 20c is provided at an end of the clip portion 20b that is not coupled to the main body portion 20a. The battery contact 20c is connected to the main body 20a via a conductive wire embedded in the clip 20b. When the user fits the clip portion 20b into the flange portion of the wheel rim 14 and fixes the battery 20 to the wheel rim 14, the battery contact 20c provided at the tip of the clip portion 20b contacts the wheel rim second contact 31. . Even in this case, the relative positional relationship between the battery 20 and the wheel rim 14 is regulated to the battery 20 or the wheel rim 14 so that the battery contact 20c and the wheel rim second contact 31 can be easily brought into contact with each other. A guide may be provided. Moreover, the mark etc. which show the relative attachment position of the circumferential direction of the battery 20 and the wheel rim 14 may be provided in the battery 20 or the wheel rim 14.

  As described above, by attaching the clip portion 20 b to the flange portion of the wheel rim 14, the battery 20 is electrically connected to the strain gauge 18, the wireless transmitter 22, and the air pressure sensor 24 through the conductive wire 34. . As a result, the power stored in the battery 20 can be supplied to the strain gauge 18, the wireless transmitter 22, or the air pressure sensor 24. Therefore, the battery 20 functions as a battery that supplies power to the strain gauge 18, the wireless transmitter 22, the air pressure sensor 24, and the like.

  The present invention is not limited to the above-described embodiment, and an appropriate combination of the elements of this embodiment is also effective as an embodiment of the present invention. Also, various modifications such as design changes can be added to this embodiment based on the knowledge of those skilled in the art, and embodiments to which such modifications are added can also be included in the scope of the present invention. Here are some examples.

  Instead of the strain gauge 18 or together with the strain gauge 18, an acceleration sensor may be provided. Similar to the strain gauge 18, the acceleration sensor may be embedded in the rubber layer of the tread portion 12 a of the tire 12 or may be attached to the inner surface of the tire 12. Further, the acceleration sensor may be supplied with electric power from the battery 20 via the conductive wire 28 embedded in the tire 12 or the conductive wire 34 embedded in the wheel rim 14. As a result, the acceleration of the tread portion 12a as a place where the tire 12 is installed on the road surface can be detected, and various vehicle controls such as an electronically controlled brake system and a traction control system are executed by using the detection result. It becomes possible to do.

  Wheels other than the battery 20 or the battery 20 so that the wireless transmitter 22, the air pressure sensor 24, the strain gauge 18 and the like as components of the wheel sensor device 50 other than the battery 20 and the battery 20 have substantially the same weight. A balance weight may be arranged on the component side of the sensor device 50. Accordingly, it is possible to further suppress the weight imbalance in the circumferential direction of the wheel 10 by providing the wheel sensor device 50.

  The components of the wheel sensor device 50 may be distributed on the circumferential direction of the wheel 10 at three or more locations and arranged on the wheel 10. For example, the wireless transmitter 22, the air pressure sensor 24, and the battery 20 may be distributed in the circumferential direction of the wheel 10 and disposed on the wheel 10. Also by this, it becomes possible to suppress the imbalance of the weight in the circumferential direction of the wheel 10 by providing the wheel sensor device 50. In such a case, the components of the wheel sensor device 50 may be arranged at substantially equal intervals in the circumferential direction of the wheel 10. That is, the components of the wheel sensor device 50 may be arranged on radiation that is opened at predetermined angles in the circumferential direction of the wheel 10. In addition, balance weights may be arranged in the vicinity of one or a plurality of components so that the components arranged in the circumferential direction of the wheel 10 at three or more locations have substantially the same weight. Further, when the weight of each of the plurality of groups or the plurality of components is different, the distance from the central axis of the wheel 10 is set so that the center of gravity of the component constituting the wheel sensor device 50 is substantially the center of the wheel 10. They may be arranged differently on the wheel 10. In this way, by arranging the center of gravity of the components constituting the wheel sensor device 50 to be substantially the center of the wheel 10, the weight imbalance in the circumferential direction of the wheel 10 due to the provision of the wheel sensor device 50 is further increased. It becomes possible to suppress.

  The tire 12 in which the strain gauge 18 is not embedded may be used. Even in this case, the wireless transmitter 22, the air pressure sensor 24, and the battery 20 are dispersed in the circumferential direction of the wheel 10 and disposed on the wheel 10, thereby suppressing weight imbalance in the circumferential direction of the wheel 10. it can.

  A plurality of strain gauges 18 may be dispersed in the circumferential direction of the tire 12 and embedded in the tire 12. Even in this case, the plurality of strain gauges 18 dispersed and embedded in the tire 12 are supplied with electric power from the battery 20 by being connected to the conductive wires 34 embedded in the wheel rim 14 in the circumferential direction via contacts. Can receive. Also in this case, each of the plurality of strain gauges 18 is connected to the wireless transmitter 22, and each detection result is transmitted wirelessly to a receiver provided on the vehicle body.

It is a front view of the wheel by which the wheel sensor device concerning this embodiment was carried. It is A sectional drawing of the wheel by which the wheel sensor apparatus which concerns on this embodiment was mounted.

Explanation of symbols

  10 wheels, 12 tires, 14 wheel rims, 16 wheel sensor units, 18 strain gauges, 20 batteries, 22 wireless transmitters, 24 air pressure sensors, 50 wheel sensor devices.

Claims (7)

A wheel sensor device including at least components as detection means for detecting the state of the wheel, transmission means for transmitting the detected wheel state information to the vehicle body, and a battery for supplying power to the detection means or the transmission means In
The wheel sensor device according to claim 1, wherein the components constituting the wheel sensor device are divided into a plurality of groups, and the plurality of groups are distributed in a wheel circumferential direction and arranged on the wheel.   2. The wheel sensor device according to claim 1, wherein the plurality of groups are distributed in a wheel circumferential direction and arranged on a wheel such that a center of gravity of the wheel sensor device is positioned at a substantially center of the wheel.   The wheel sensor device according to claim 2, wherein the plurality of groups are arranged on the wheel in a distributed manner on radiation opened at an angle of approximately 180 ° in the wheel circumferential direction.   4. The wheel sensor device according to claim 1, wherein one of the plurality of groups is configured by the battery. 5.   The wheel sensor device according to any one of claims 1 to 4, wherein the battery is disposed in a vehicle outer direction from a wheel rim surface facing the vehicle outer side.   The wheel sensor device according to any one of claims 1 to 5, wherein the detection means is an air pressure sensor that is provided in a tire chamber and detects an air pressure of the tire.   The wheel sensor according to any one of claims 1 to 5, wherein the detection means is a strain gauge provided on a rubber layer or an inner surface of the tire to detect deformation of the tire or force applied to the tire. apparatus.

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