JP2008143344A - Tire information transmitting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire information transmitting device having a structure capable of suppressing looseness of mounting to a wheel. <P>SOLUTION: By using centrifugal force applied to the radial direction outer side of the tire due to traveling rotation of the tire, the tire information transmitting device 10 rotates a screw part 32b for fixing the tire information transmitting device 10 to a wheel rim to a fastening direction with respect to a nut 38. Since a substrate 44 and a battery 46 stored inside a housing 34a of a sensor unit 34 are arranged in a position separated from the rotation center axis M of the screw part 32b, the gravity center G of the sensor unit 34 is separated from the rotation center axis M so as to enable rotation of the sensor unit 34 by the centrifugal force. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a tire information transmission device, and more particularly to an improvement in a structure for fixing the tire information transmission device to a wheel.

When the vehicle tire is at a lower pressure or higher temperature than the recommended state, not only the tire's original performance cannot be exhibited, but there is a possibility that the reliability of the tire may be lowered when used for such a long period. For this reason, various techniques for monitoring tire information indicating the tire pressure and temperature and other tire conditions have been proposed. For example, there is a tire information transmission device in which a pressure sensor that measures tire air pressure is disposed inside a tire and the measured value is transmitted to the vehicle side wirelessly. Such a pressure sensor and transmitter of the tire information transmitting apparatus are assembled inside a tire mounted on a wheel. In consideration of the ease of assembly work, the tire valve may be integrated with the tire valve used when air is taken in and out of the tire. The tire valve is inserted into a mounting hole formed in the rim portion of the wheel, one end is exposed to a tire chamber (pressure space) formed by the wheel and the tire, and the other end is exposed to the surface of the wheel. By connecting the pressure sensor and transmitter to one end of the tire valve exposed in the tire chamber, the pressure sensor and transmitter can be assembled and fixed to the wheel without changing the wheel mounting structure from the conventional one ( For example, see Patent Document 1).
Japanese Patent Laid-Open No. 10-44726

  In the case of an apparatus in which a tire valve, a sensor, and a transmitter are integrated as disclosed in Patent Document 1, a rubber grommet is attached to an attachment hole formed in a wheel rim. The tire valve is fixed to the wheel rim with a washer and a nut through this grommet. However, the grommet made of a rubber material has a lower elastic force due to aging. When the elastic force of the grommet is reduced, the substantial thickness of the grommet is reduced, and a gap is formed between the grommet and the wheel rim. As a result, the nut may be in the same state as when it is loosened, and the tightening torque by the nut may not be maintained constant. Further, the nut may be loosened due to vibration during traveling. In these cases, there is a possibility that the tire information transmission device is loosely attached to the wheel and the tire air pressure leaks.

  This invention is made | formed in view of such a condition, The place made into the objective is providing the tire information transmitter which has the structure which can suppress loosening of the attachment with respect to a wheel.

  In order to solve the above problems, a tire information transmitting device according to an aspect of the present invention is connected to a valve body for taking in and out gas inside a tire, the valve body, and the state information of the tire. A sensor unit that acquires and transmits at least a part of the acquired state information to the outside, and a screw part formed on one of the valve body or the sensor unit, and the valve body and the sensor A screwing member that fixes the unit to the wheel together, and the sensor unit receives a centrifugal force generated by the rotation of the tire and rotates the screw part in a tightening direction with respect to the screwing member. In order to generate a force, the screw portion has a center of gravity at a position away from the rotation center axis.

  When the tire rotates, anything having a mass on and inside the tire is affected by centrifugal force. On the other hand, the sensor unit includes a sensor for acquiring tire state information, a substrate including a transmitter for transmitting the state information acquired by the sensor to the outside, a battery for driving the sensor and the transmitter, and the like. ing. Therefore, a sensor, a transmitter, a substrate, a battery, and the like are arranged in a housing forming the sensor unit so that the center of gravity is formed at a position separated from the rotation center axis of the screw portion. That is, the sensor unit is used as a weight such as a sensor, a transmitter, a substrate, or a battery, and a centrifugal force is applied to the weight to generate a rotational force of the screw portion. Therefore, for example, when the screw part is a right-hand thread, if the center of gravity of the sensor unit is on the left side of the center axis of the screw part, the screw part can be rotated in the tightening direction by receiving the centrifugal force. The rotational torque generated by the center of gravity of the sensor unit is always generated when the tire rotates. Therefore, when the screw portion is loosened, the screw portion is rotated, and the screw portion can be always tightened with the optimum tightening torque.

  In order to solve the above problems, a tire information transmitting device according to an aspect of the present invention is connected to a valve body for taking in and out gas inside a tire, the valve body, and the state of the tire. A sensor unit that acquires information and transmits at least a part of the acquired state information to the outside, and is screwed with a screw portion formed on one of the valve body or the sensor unit, and the valve body and A screwing member that fixes both the sensor units to the wheel and a centrifugal force generated by the traveling rotation of the tire so as to generate a rotational force that rotates the screw part in a tightening direction with respect to the screwing member. And a rotation generating part for providing a center of gravity at a position away from the rotation center axis of the screw part.

  For example, when the screw part is a right-hand thread, if the center of gravity of the rotation generating part is on the left side of the center axis of the screw part, the rotation generating part receives centrifugal force, so that the screw part can be rotated in the tightening direction. it can. The rotation generating unit can be connected to, for example, at least one of the valve body and the sensor unit. For example, one end of the rod-shaped member is connected to the valve body or the sensor unit, and a large weight, for example, a weight is provided on the other end side. It can be configured by connecting. The rotational torque generated by the rotation generator is always generated when the tire rotates. Therefore, when the screw portion is loosened, the screw portion is rotated, and the screw portion can be always tightened with the optimum tightening torque.

  Further, in the above aspect, the apparatus includes a one-way torque transmission mechanism that transmits only a rotational torque that rotates the screw part in a tightening direction with respect to the screwing member when a rotational force is applied by the centrifugal force. But you can. When the rotation of the tire stops and the centrifugal force disappears, the rotation generator or sensor unit that applied the rotational force to the screw part rotates the screw part in the direction opposite to the tightening direction of the screwing member. May end up. Therefore, the rotational torque generated by the rotation generator and the sensor unit is transmitted only when the screw portion is rotated in the tightening direction with respect to the screwing member. In other words, the reverse rotational torque generated in the rotation generating part or the sensor unit is not transmitted to the screw part, and there is no possibility that the screw part is loosened. As a result, loosening of the screw part and the screwing member due to the disappearance of the centrifugal force is prevented.

  Moreover, the said aspect WHEREIN: The said one-way torque transmission mechanism may have a reverse rotation prohibition mechanism which prohibits that the said thread part rotates in the reverse direction to the fastening direction of the said screwing member. The reverse rotation prohibiting mechanism can be constituted by, for example, a ratchet mechanism. According to this aspect, the tightening operation is performed every time the tightening operation by the centrifugal force is performed according to the looseness of the screw portion and the screwing member, and the rotation state is locked in the optimum tightening torque state. Is called. As a result, the optimum tightening torque state can be maintained.

  ADVANTAGE OF THE INVENTION According to this invention, the tire information transmission apparatus which has a structure which can suppress loosening of attachment can be provided.

  The best mode for carrying out the present invention will be described below in detail with reference to the drawings.

  The tire information transmission device according to the present embodiment uses a centrifugal force that acts on the outer side in the radial direction of the tire due to the traveling rotation of the tire, and a screw portion that fixes the tire information transmission device to the wheel rim with respect to the screwing member. Rotate in the tightening direction. Centrifugal force acts on a rotation generation unit having a center of gravity at a position separated from the rotation center axis of the screw member or a sensor unit included in the basic configuration of the tire information transmitting device, and generates a rotation force on the screw unit.

  FIG. 1 is a conceptual configuration diagram of a vehicle 14 equipped with wheels 12 having a tire information transmitting apparatus 10 according to the present embodiment. Each wheel 12 has a tire and a wheel. The tire information transmitting apparatus 10 can include a sensor that acquires various state information of the wheel 12 (tire). For example, it is possible to acquire air pressure information and temperature information in the tire, impact force information on the tire, road surface resistance information, and the like. In addition, the transmitter includes a transmitter that selects all of the acquired tire state information or only necessary information and wirelessly transmits a part thereof to the receiver 18 disposed on the vehicle body 16 side. In this case, the tire information transmitting apparatus 10 may process the acquired state information as appropriate and transmit the result. In addition, the kind of sensor contained in the tire information transmission apparatus 10 can be selected suitably, and can be changed according to a purpose of use.

  The vehicle body 16 is equipped with a tire monitoring system main body 20 that monitors tires based on tire state information transmitted from the tire information transmitting device 10. The tire monitoring system main body 20 includes a receiver 18 that receives state information transmitted from the tire information transmitting device 10 and an electronic control unit (hereinafter referred to as “ECU”) that performs tire state determination based on the received state information. ) 22 and a display device 24 for notifying a user such as a driver of the determination result by the ECU 22. In the case of this embodiment, ID is attached | subjected for every wheel 12 in the status information which the tire information transmitter 10 transmits. Further, the ECU 22 holds a reference ID for identifying the ID. Therefore, the ECU 22 can determine from which wheel 12 the acquired tire state information has been transmitted, and can individually monitor the wheel 12, for example, manage the tire pressure.

  FIG. 2 is a part of a cross-sectional view of the wheel 12 (tire 26) equipped with the tire information transmitting device 10 of the present embodiment. The tire 26 in FIG. 2 shows a so-called run flat tire as an example. A run-flat tire is a tire that can run at 80 km at a speed of 90 km / h, for example, when the air pressure drops, for example, even when the air pressure is zero, the deformation of the tire is constrained by the internal structure of the tire. Typical structures of run flat tires include a side wall reinforcing type and a core type. FIG. 2 shows a side wall reinforcing type run flat tire in which a reinforcing rubber 28 is disposed in a side wall portion. In addition, the tire information transmission apparatus 10 of this embodiment is applicable also to the wheel 12 equipped with general tires other than run-flat tires, and can obtain the same effect as this embodiment shown below.

  The tire information transmitting apparatus 10 according to the present embodiment acquires the state information of the valve body 32 and the tire 26 for taking in and out the gas from the tire chamber 30 of the tire 26, and at least part of the state information is externally transmitted. The sensor unit 34 for transmitting to is integrated. The wheel 12 has a wheel 36 and a tire 26. A wheel rim 36 a formed in a cylindrical shape is provided on the outer periphery of the wheel 36. The tire 26 is assembled on the outer periphery of the wheel rim 36a. A tire air chamber 30 is formed in an internal space surrounded by the inside of the tire 26 and the outer periphery of the wheel rim 36a. The valve body 32 is fixed to a mounting hole 36b formed in the wheel rim 36a by a screwing member such as a nut 38. When the valve body 32 is attached to the attachment hole 36b, a cylindrical grommet 40 having a flange 40a is inserted into the attachment hole 36b for the purpose of ensuring the airtightness of the tire air chamber 30. The grommet 40 is an elastic body formed of a rubber material or the like, and is capable of securing the airtightness of the mounting portion by being compressed and deformed at the time of mounting. The valve body 32 is a cylindrical part having an air supply hole 32a penetrating in the axial direction, and a screw part 32b is formed on the outer periphery thereof. A nut 38 is screwed into the screw portion 32b. In the valve body 32, when the nut 38 is tightened, the washer 42 and the flange 40a of the grommet 40 sandwich the wheel rim 36a to fix the valve body 32 to the wheel rim 36a. In the present embodiment, the sensor unit 34 is connected and fixed to one end of the valve body 32. In the case of FIG. 2, the air supply hole 32 a passes through the inside of the sensor unit 34 and is opened to the tire air chamber 30.

  FIG. 3 is a schematic diagram illustrating the internal structure of the sensor unit 34. The sensor unit 34 includes a substrate 44 and a battery 46 inside a housing 34a. The substrate 44 includes a sensor circuit that acquires state information from a pressure sensor (not shown) that measures the air pressure in the tire chamber 30 that is state information of the tire 26. Moreover, the sensor circuit which acquires the status information from the temperature sensor (not shown) which measures the temperature of the inside of the tire air chamber 30, a tread part, or a sidewall part is provided. Furthermore, a transmitter that wirelessly transmits the state information acquired by the sensor to the receiver 18 on the vehicle body 16 side is provided. In addition, as described above, the air supply hole 32a of the valve body 32 passes through the housing 34a so that air can be taken into and out of the tire chamber 30.

  By the way, as described above, the valve body 32 of the tire information transmitting device 10 is equipped with the rubber grommet 40 in order to maintain the airtightness of the tire air chamber 30. However, since this grommet 40 is made of rubber, it is unavoidable that it will deteriorate over time. As rubber deteriorates, its elasticity decreases. When the elastic force of the grommet 40 is reduced, the substantial thickness of the grommet 40 is reduced, and a gap is generated between the grommet 40 and the wheel rim 36a. That is, the substantial tightening force by the nut 38 is reduced, and the air tightness of the tire chamber 30 cannot be maintained. Further, the valve body 32 connecting the sensor unit 34 cannot be fixed, and the valve body 32 and the sensor unit 34 may be damaged. That is, when the grommet 40 deteriorates over time, the same problem as when the nut 38 itself is loosened by vibration or the like occurs, and torque management related to fixing the tire information transmitting device 10 may not be sufficiently performed.

  Therefore, the tire information transmitting apparatus 10 according to the present embodiment has the tire information transmitting apparatus 10 tightened by itself when the valve body 32 is loosely fixed due to aging of the grommet 40 or loosening of the nut 38 itself. It has a structure that operates and maintains an optimum tightening torque state.

  When the tire 26 is rotated by traveling or the like, a centrifugal force directed outward in the radial direction of the tire 26 acts. In other words, centrifugal force also acts on the sensor unit 34 connected to the valve body 32. Thus, in the present embodiment, the centrifugal force is used to perform the screwing tightening operation of the tire information transmitting device 10. That is, by rotating the sensor unit 34 by centrifugal force, the screw portion 32 b of the valve body 32 connected to the sensor unit 34 is rotated in the tightening direction with respect to the nut 38. Therefore, the center of gravity of the sensor unit 34 is set at a position separated from the rotation center axis M of the screw portion 32b. In the present embodiment, the substrate 44 and the battery 46 are heavy components heavier than the mass of the housing 34a in the housing 34a. Therefore, the position of the center of gravity G of the housing 34a can be easily moved by disposing the substrate 44 and the battery 46 at positions separated from the rotation center axis M in the housing 34a. By separating the center of gravity G from the rotation center axis M, a rotational moment acts on the rotation center axis M due to centrifugal force acting on the center of gravity G, and the sensor unit 34 rotates about the rotation center axis M. In the case of this embodiment, as shown in FIG. 2, the sensor unit 34 is connected to the valve body 32 with an angle α due to the relationship between the shape of the wheel 36 and the mounting position of the valve body 32. . As a result, the centrifugal force component F 1 perpendicular to the rotation center axis M rotates the sensor unit 34 with respect to the centrifugal force F 0 acting on the sensor unit 34. Then, the screw portion 32b of the valve body 32 to which the sensor unit 34 is connected is rotated in the tightening direction with respect to the nut 38. In the case of the present embodiment, a washer 42 is disposed between the nut 38 and the wheel rim 36a and there is a frictional resistance, so that the nut 38 is stationary due to the frictional resistance when the screw portion 32b is loosened at an early stage. Therefore, when the screw portion 32b rotates, the screwing of the screw portion 32b and the nut 38 in the tightening direction proceeds.

  FIG. 4 is an explanatory diagram for explaining the rotation operation when the sensor unit 34 receives centrifugal force. In the case of FIG. 4, in order to simplify the explanation, the rotation center axis M of the valve body 32 is arranged at the center of the XY coordinate system, and the centrifugal force acts in the positive direction of the Y axis. Further, the case where the sensor unit 34 is fixed at a right angle (without the angle α in FIG. 2) with respect to the rotation center axis M of the valve body 32 is shown. In this case, the sensor unit 34 is rotated by the centrifugal force F0 in FIG. In the case of the present embodiment, the screw portion 32b is fastened to the nut 38 when rotated in the clockwise direction (right screw direction). That is, the sensor unit 34 may be rotated in the clockwise direction A by the centrifugal force F0. By the way, in the configuration as described above, when the centrifugal force F0 acts in the positive Y-axis direction of FIG. 4, the sensor unit 34 needs to be positioned in the second quadrant or the third quadrant of the XY coordinate system. If the sensor unit 34 exists in the first quadrant or the second quadrant, and the centrifugal force F0 in the Y-axis positive direction is applied, the sensor unit 34 rotates counterclockwise, that is, in the direction in which the screw portion 32b is loosened. End up. In addition, when the screw part 32b is a left-hand thread, the position where the sensor unit 34 exists is reverse to the above-described case and needs to be in the first quadrant and the second quadrant.

  In order to efficiently rotate the sensor unit 34 by applying the centrifugal force F0, the sensor unit 34 is preferably located in the second quadrant. When the sensor unit 34 is allowed to be positioned in the third quadrant in the initial stage (the stage where the grommet 40 is not deteriorated), the adjustment rotation amount of the tightening torque due to the rotation of the sensor unit 34 is 180 ° at the maximum. Further, when the sensor unit 34 is allowed to be positioned in the second quadrant in the initial stage, the adjustment rotation amount of the tightening torque by the rotation of the sensor unit 34 is 90 ° at the maximum. However, since the looseness of the screw portion 32b due to the aging of the grommet 40 is slight, an adjustment amount of about 90 ° is sufficient.

  In this way, the sensor unit 34 can be rotated by the centrifugal force generated when the tire 26 is running and rotated, and the screw portion 32 b can be rotated in the direction of tightening the nut 38. As a result, even when the threaded portion 32b is substantially loosened due to aging degradation of the grommet 40, it is possible to apply a tightening torque each time the tire 26 travels, and the wheel rim of the tire information transmitting device 10 can be applied. The fixing to 36a can be maintained in an optimum state with no gap. That is, the airtightness of the tire air chamber 30 of the tire 26 can be maintained regardless of the state of the grommet 40. In rare cases, the nut 38 is loosened due to vibration or the like while the vehicle 14 is traveling. Even in such a case, the sensor unit 34 can be rotated by the centrifugal force at the time of traveling, and the screw portion 32b can be rotated to be fastened to the nut 38. As a result, the fixing of the tire information transmitting apparatus 10 to the wheel rim 36a can be maintained in an optimal state with no gap as described above. That is, the air tightness of the tire air chamber 30 of the tire 26 can be maintained.

  FIGS. 5A and 5B show an example of a washer 42 used when the tire information transmitting apparatus 10 of the present embodiment is fixed to the wheel rim 36a with a nut 38. FIG. FIG. 5B is a CC cross section of FIG. Normally, the washer 42 is mounted to prevent the nut 38 from loosening. However, when the grommet 40 deteriorates with age and its elasticity decreases, the washer 42 rotates due to external force, for example, vibration during running, The nut 38 may be loosened. Therefore, the washer 42 according to the present embodiment has a locking projection 42a as shown in FIGS. 5A and 5B so that the grommet 40 does not rotate even if the grommet 40 is aged. . Further, as shown in FIG. 5C, the wheel rim 36a is formed with a recess 36c that engages with the locking projection 42a. Prior to the use of the nut 38, as shown in FIG. 5D, the locking projection 42a and the recess 36c are engaged to prevent the washer 42 from rotating, that is, loose rotation due to external force such as vibration of the nut 38. In the case of FIG. 5C, the storage recess 36d in which the washer 42 fits is formed on the wheel rim 36a. However, the formation of the storage recess 36d is arbitrary, and only the recess 36c is formed on the surface of the wheel rim 36a. May be formed. 5 (a) to 5 (d) show an example in which a convex locking protrusion 42a is provided on the washer 42 side. However, a concave portion is provided on the washer 42 side, and a convex portion is provided on the wheel rim 36a side. May be provided. In this case, the same effect as in the above example can be obtained.

  By the way, in the case of the configuration of the tire information transmitting apparatus 10 shown in FIG. 2, the rotational torque that rotates the screw portion 32 b in the tightening direction with respect to the nut 38 disappears when the centrifugal force disappears. As described with reference to FIG. 4, the tire information transmitting device 10 is centrifugally moved because the sensor unit 34 is rotated by the centrifugal force and the nut 38 presses the wheel rim 36 a via the washer 42, so that the tire information transmitting device 10 is strongly fastened. After the disappearance, the sensor unit 34 is unlikely to rotate in the reverse direction and loosen the screwing. However, as shown in FIG. 4, since the sensor unit 34 is in an unstable posture rising from the initial arrangement posture, there is a possibility that the sensor unit 34 rotates in the direction of loosening the screwing due to gravity. . Therefore, in the example of FIG. 6, when a rotational force is applied by a centrifugal force, a one-way torque transmission mechanism that transmits only the rotational torque that rotates the screw portion 32 b in the tightening direction with respect to the nut 38 to the screw portion 32 b is provided. Yes. As the one-way torque transmission mechanism, for example, a ratchet mechanism 48 having a reverse rotation prohibiting mechanism can be used. For example, when the sensor unit 34 rotates in the tightening direction due to centrifugal force, the rack gear and the claw portion of the ratchet mechanism 48 are engaged, and the rotation of the sensor unit 34 is transmitted to the screw portion 32b side. On the other hand, when the centrifugal force disappears and the sensor unit 34 tries to rotate in the direction opposite to the tightening direction due to gravity or the like, the rack gear and the claw portion are disengaged and idle. As a result, the sensor unit 34 returns to the original posture, that is, the posture when the grommet 40 is not deteriorated over time without causing the screw portion 32b and the nut 38 to loosen. When the centrifugal force is applied again to the sensor unit 34, the rotation of the sensor unit 34 is transmitted to the screw portion 32b side by the engagement between the rack gear and the claw portion, and the screw portion 32b and the nut 38 are tightened.

  When the tire information transmitting apparatus 10 does not have a one-way torque transmission mechanism, as described in FIG. 4, the rotation range of the sensor unit 34 is limited to the second quadrant and the third quadrant in FIG. there were. As described above, the retightening for coping with the aging deterioration of the grommet 40 is sufficient if it is rotated by 180 °. However, the rotation amount may be insufficient, for example, when the screw pitch of the screw portion 32b is fine or when the grommet 40 is damaged. In addition, depending on the shape of the wheel rim 36a on which the tire information transmitting device 10 is disposed, the sensor unit 34 and the wheel rim 36a or other components may interfere with each other to ensure a sufficient rotation angle.

  On the other hand, as shown in FIG. 6, if a one-way torque transmission mechanism is provided in the tire information transmitting apparatus 10 and the sensor unit 34 is returned to the original posture every time the centrifugal force disappears, the centrifugal force is applied. Further, the sensor unit 34 is rotated by a small angle, and a small amount of retightening is repeated. That is, even if the amount of one rotation is small, a sufficient tightening angle can be obtained by accumulating the amount of rotation. As a result, it is possible to tighten more than 180 °. In this case, the tightening operation is executed by repeatedly running and stopping the vehicle, so that the tightening is performed smoothly. In addition, since the magnitude of the centrifugal force changes due to increase / decrease in traveling speed, rotation in the tightening direction and return rotation of the sensor unit 34 occur, so that the tightening operation can be performed.

  In the case of the configuration of FIG. 3, the center of gravity G of the sensor unit 34 is moved from the rotation center axis M by separating the arrangement positions of the substrate 44 and the battery 46 in the housing 34 a from the rotation center axis M. In FIG. 7, the position of the center of gravity of the sensor unit 34 is changed by another configuration. In the case of the example in FIG. 7, the substrate 44 and the battery 46 are disposed in the vicinity of the rotation center axis M (for example, immediately below the valve body 32). Then, in response to the centrifugal force generated by the traveling rotation of the tire 26, the screw portion 32b is separated from the rotation center axis M so as to generate a rotational force that rotates the screw portion 32b in the tightening direction with respect to the nut 38. A weight 50 is disposed as a rotation generating portion that forms the center of gravity G. The weight 50 can be connected to the housing 34a of the sensor unit 34 by a connection bar 52, for example. In this case, the tightening torque when the centrifugal force is received can be adjusted by adjusting the mass of the weight 50, or by changing the position of the center of gravity G by changing the length of the connection bar 52. is there. As a result, the tightening torque can be set according to the characteristics of the wheel 12 and the vehicle 14 without redesigning the shape of the housing 34a, the arrangement form of the substrate 44, and the battery 46 for each tire type and vehicle type. . In the example of FIG. 3, a weight arrangement space may be provided inside the housing 34a. In this case, even in the configuration of FIG. 3, the position of the center of gravity G can be changed, and the characteristics for each tire type and vehicle type can be dealt with.

  In the present embodiment, an example in which the sensor unit 34 is connected to the screw portion 32b formed in the valve body 32 is shown. That is, although the screw unit 32b of the valve body 32 is rotated by the sensor unit 34 rotated by the centrifugal force and screwed with the nut 38, the screw unit rotated by the centrifugal force is provided on the sensor unit 34 side. It may be. In this case, the screw part formed in the sensor unit 34 protrudes outward from the tire chamber 30 via the mounting hole 36b, and the nut 38 and the valve body are disposed on the tip. Even in this configuration, the same effect as the above-described embodiment can be obtained.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added based on the knowledge of those skilled in the art. The configuration shown in each figure is for explaining an example, and any configuration that can achieve the same function can be changed as appropriate, and the same effect can be obtained.

It is a conceptual lineblock diagram of vehicles equipped with a wheel which has a tire information transmitting device concerning this embodiment. It is a part of sectional drawing of the wheel (tire) which equipped with the tire information transmitting device concerning this embodiment. It is the schematic explaining the internal structure of the sensor unit of the tire information transmitter which concerns on this embodiment. It is explanatory drawing explaining rotation operation when the sensor unit of the tire information transmitter concerning this embodiment receives centrifugal force. It is explanatory drawing which shows an example of the washer used when the tire information transmitter which concerns on this embodiment is fixed to a wheel rim with a nut. It is a composition conceptual diagram at the time of applying a one-way torque transmission mechanism to the tire information transmitting device concerning this embodiment. It is explanatory drawing explaining another structure of the tire information transmission apparatus which concerns on this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Tire information transmitter, 12 Wheel, 14 Vehicle, 16 Car body, 18 Receiver, 20 Tire monitoring system main body, 22 ECU, 24 Display apparatus, 26 Tire, 30 Tire air chamber, 32 Valve body, 32b Screw part, 34 Sensor Unit, 34a housing, 36 wheel, 36a wheel rim, 38 nut, 40 grommet, 42 washer, 44 substrate, 46 battery, 48 ratchet mechanism, 50 weight, 52 connection bar, M rotation center shaft.

Claims (4)

A valve body for taking in and out the gas inside the tire;
A sensor unit that is connected to the valve body, acquires state information of the tire, and transmits at least part of the acquired state information to the outside.
A threaded member that is threadedly engaged with a threaded portion formed on either the valve body or the sensor unit, and that fixes both the valve body and the sensor unit to the wheel;
Including
The sensor unit receives a centrifugal force generated by rotation of the tire and generates a rotational force that rotates the screw portion in a tightening direction with respect to the screwing member. A tire information transmission device having a center of gravity at a spaced position. A valve body for taking in and out the gas inside the tire;
A sensor unit that is connected to the valve body, acquires state information of the tire, and transmits at least part of the acquired state information to the outside.
A threaded member that is threadedly engaged with a threaded portion formed on either the valve body or the sensor unit, and that fixes both the valve body and the sensor unit to the wheel;
The center of gravity is located at a position away from the rotation center axis of the screw portion so as to generate a rotational force that rotates the screw portion in a tightening direction with respect to the screwing member in response to the centrifugal force generated by the running rotation of the tire. A rotation generating part for holding
A tire information transmitting device comprising:   A one-way torque transmission mechanism that transmits only a rotational torque for rotating the screw portion in a tightening direction with respect to the screwing member to the screw portion when a rotational force is applied by the centrifugal force. The tire information transmitting device according to claim 1 or 2.   The tire information transmitting apparatus according to claim 3, wherein the one-way torque transmission mechanism includes a reverse rotation prohibiting mechanism that prohibits the screw portion from rotating in a direction opposite to a tightening direction of the screwing member.

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