JP2004359035A - Tire air pressure control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tire air pressure control device where an accommodation form of a component mounted to a tire side does not interfere with a wheel nut. <P>SOLUTION: The tire air pressure control device is equipped with a control wire 4 which is connected to a valve of a tire and has a valve pin of the valve, a stepping motor 3 discharging air in the tire by pressing the valve pin, a control board 2 receiving a control signal for driving a stepping motor 3 from the outside, a battery 5 supplying power to the stepping motor 3 by receiving the control signal from the control board 2, and an outside transmitter transmitting the control signal to the control board 2. The stepping motor 3, the control board 2, and the battery 5 are constituted so as to be accommodated in a cylindrical case 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a tire air pressure control device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, as a system for detecting tire puncture early, for example, in order to make a driver aware of a decrease in tire air pressure while a car is running, air pressure decrease monitoring that detects a decrease in tire air pressure based on the rotation speed of four wheels There is a system (for example, see Patent Document 1).
[0003]
[Patent Document 1]
JP-B-48-6829 [0004]
In recent years, such air pressure drop monitoring systems have been regarded as important with the spread of US regulations and run-flat tires, and thus need to be evaluated by an optimum performance evaluation test in order to improve their performance. Further, such a performance evaluation test required a device for intentionally bleeding air from the tire in order to know whether or not the system can normally detect a decrease in air pressure.
[0005]
The applicant has already filed a Japanese Patent Application No. 2002-315237 (not disclosed) as a device (pneumatic pressure control device) for deflating the tire.
FIG. 6 is an exploded perspective view of the above-described air pressure control device.
In the air pressure control device 100 described in Japanese Patent Application No. 2002-315237, when a control signal is input from an external transmitter 101 outside the vehicle, the control signal is pressed via a tire-side receiver 102 provided on the tire T side. It is transmitted to the device 103. Then, based on the control signal, the control wire 104 connected to the pressing device 103 presses the valve pin of the valve B provided on the tire T, and releases the air in the tire T. With such a configuration, the air in the tire T can be evacuated by a predetermined amount at a predetermined time, and the pressure reduction in the tire T during the running of the vehicle, which cannot be conventionally performed, can be performed.
[0006]
In such a pneumatic pressure control device 100, a fixing board 105 to which components such as a tire-side receiver 102 and a pressing device 103 provided on the tire T are joined and fixed to a wheel flange 106 with a screw 107 is attached. The lid 108 covers the fixing board 105 from above. The wheel flange 106 is fixed to the wheel W by a wheel nut 109, and each component is fixed to the tire T side. The screw 107 and the wheel nut 109 are provided at positions where they do not interfere with each other.
[0007]
[Problems to be solved by the invention]
However, at the time of filing the application for Japanese Patent Application No. 2002-315237, the present applicant did not particularly describe an optimal form when each component of the air pressure control device 100 is mounted on the tire T side. For this reason, there is a point to be improved in the storage form of each component provided on the tire T side.
[0008]
That is, in the air pressure control device 100 described above, the fixed board 105 is attached to the wheel flange 106 with the screw 107, but it is not preferable that the fixed board 105 interferes with the wheel nut 109 in design. On the other hand, the number, position, and the like of the wheel nuts 109 for fixing the wheel flange 106 to the wheel W differ depending on each manufacturer. Therefore, depending on the type of the wheel W, the position of the wheel nut 109 and a part of the fixed board 105 may interfere with each other. Therefore, the fixing board 105 must be selected such that the wheel nut 109 does not interfere with each time of mounting, and there is a problem that it takes time and effort.
[0009]
In addition, since the centrifugal force due to the rotation of the tire T is applied to each component while the vehicle is running, there is a problem that the components tend to fall off depending on the balance of the center of gravity of each component and the layout at the time of mounting.
[0010]
Then, this invention is made in order to solve the said problem, and makes it a subject to provide the tire pressure control apparatus in which the storage form of the component attached to a tire side does not interfere with a wheel nut. .
[0011]
[Means for Solving the Problems]
The present invention is configured to solve the above-described problem, and the invention according to claim 1 is connected to a valve of a tire, by pressing a control wire having a valve pin of the valve, and pressing the valve pin. A pressing device that releases air in the tire, a tire-side receiver that receives a control signal for driving the pressing device from outside, and a control signal from the tire-side receiver, and the pressing device A tire pressure control device including a power supply unit that supplies power and an external transmitter that transmits the control signal to the tire-side receiver, wherein the pressing device, the tire-side receiver, and the power supply unit include: It is housed in a cylindrical housing.
[0012]
According to the first aspect of the invention, the pressing device, the tire-side receiver, and the power supply unit, which are the components attached to the tire side, are housed in the cylindrical housing. Therefore, when this housing is mounted on the tire side, the housing can be arranged at the center of the axis of the wheel, and the distance from any wheel nut position to the housing can be made constant. Therefore, the housing can be attached to the wheel without interfering with the wheel nut.
[0013]
According to a second aspect of the present invention, in the tire pressure control device according to the first aspect, the pressing device is disposed at a center of the housing.
[0014]
According to the second aspect of the present invention, the heavy pressing device is disposed at the center of the housing. For this reason, it is easy to balance the center of gravity in the housing, and since the heavy pressing device is disposed at the center where the centrifugal force is not easily applied, it is possible to prevent the housing from falling off during running of the vehicle.
[0015]
According to a third aspect of the present invention, in the tire pressure control device according to the second aspect, the power supply unit includes a plurality of batteries, and the batteries are arranged around the pressing device. I do.
[0016]
According to the third aspect of the invention, in the housing, a plurality of batteries are arranged around a heavy pressing device. For this reason, the housing has a good balance of each part, and is attached to the tire side, so that the rotation balance when rotating together with the tire is improved.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of a tire pressure control device according to the present invention will be described in detail with reference to the drawings. In the drawings to be referred to, FIG. 1 is a view for explaining the assembly of a housing of a tire pressure control device according to the present embodiment to a tire, and FIG. 2 is each component of the tire pressure control device according to the present embodiment. FIG. 3 is a perspective view showing a layout inside the housing, and FIG. 4 is a plan view showing a layout inside the housing.
[0018]
The tire pressure control device 1 shown in FIG. 1 includes a control board 2, a stepping motor (pressing device) 3, a control wire 4 connected to the stepping motor 3, a battery (power supply means) 5, and an external transmitter 6. (See FIG. 2). As shown in FIGS. 2 to 4, the control board 2, the stepping motor 3, and the battery 5 are housed in a housing 7 having a smaller diameter than a PCD (Pitch Circle Diameter), and are mounted on the tire T side. Attached to. The external transmitter 6 is provided in a vehicle interior (not shown).
[0019]
As shown in FIG. 2, the housing 7 includes a cylindrical storage main body 7a having an open upper part, and a lid 7b fitted into the storage main body 7a. An air hole 7c is formed on the bottom surface of the housing body 7a so that the air inside can be discharged to the outside and the moisture resistance is improved. At the center of the lid 7b, a mounting screw 7d is provided so as to penetrate therethrough, so that the head of the mounting screw 7d can be gripped and easily fitted to the storage body 7a.
A bracket 8 is fixed in the housing body 7a with a screw V1 (see FIG. 3), and a screw hole 8a formed in the bracket 8 and a screw portion of a mounting screw 7d of the lid 7b are screwed into the housing body 7a. 7a and lid 7b are crimped. In addition, in order to improve water resistance, a watertight packing may be interposed between the housing body 7a and the lid 7b.
[0020]
The control board 2 has a function as a receiver for receiving a control signal for driving the stepping motor 3 from the external transmitter 6 and a function of a control device for controlling the stepping motor 3.
[0021]
The stepping motor 3 converts the force in the rotational direction into the force in the axial direction of the rotating shaft 3a inside, and the tip 3b is configured to be able to advance and retreat at predetermined strokes in the axial direction of the rotating shaft 3a. By projecting the distal end 3b by a predetermined stroke, a valve pin C1 (see FIG. 5) of a valve C provided on the control wire 4 described later is pressed, and the air in the tire T is discharged by a predetermined amount. Further, after the predetermined time elapses, the tip 3b is retracted by an amount corresponding to the advance, whereby the release of air is stopped.
[0022]
FIG. 5 is an exploded perspective view showing the valve pin pressed by the tip of the stepping motor.
The control wire 4 shown in FIG. 1 is a hollow tube that guides the air in the tire T to the housing 7 at the center of the wheel W. The control wire 4 is formed of a member having high rigidity in order to suppress bending due to centrifugal force and vertical vibration during running of the vehicle. One end of the control wire 4 is connected to a valve B provided on the tire T while its valve pin is constantly pressed, and the other end is fixed to the outer peripheral surface of the storage body 7a, and is connected to the valve B provided on the tire T. 3 is connected to the stepping motor 3 via a valve C having the same structure as that of FIG. That is, the air in the tire T flows from the air hole 7 c through the housing 7 by pressing the valve pin C 1 of the valve C provided on the other end side of the control wire 4 by the tip 3 b of the stepping motor 3. It is released to the outside. In the present embodiment, the control wire 4 has a structure having the valve C and the valve pin C1 on the stepping motor 3 side. However, the present invention is not particularly limited, and the control wire 4 is directly fitted to the valve B provided on the tire T. Alternatively, a structure having a valve pin may be employed.
[0023]
The battery 5 supplies power to the control board 2 and the stepping motor 3. In the present embodiment, the battery 5 is configured by connecting a plurality of AAA batteries 5a, 5b,... 5h in series. The batteries 5a,..., 5h are evenly arranged along the inner peripheral surface of the storage body 7a. By doing so, the rotation balance when attached to the wheel W and rotating with the wheel W is improved, and the storage efficiency can be improved. However, the battery 5 is not particularly limited. For example, a single battery may be used, or a plurality of plate-shaped lithium batteries connected in series may be used.
[0024]
The external transmitter 6 has a function of transmitting a control signal for driving the stepping motor 3 to the control board 2. The wireless communication between the control board 2 and the external transmitter 6 can use an analog method using FM modulation or a digital method using PCM modulation. The communication direction may be one-way communication from the external transmitter 6 to the control board 2 or two-way communication.
[0025]
Here, the arrangement of the components included in the housing 7 will be described.
As shown in FIGS. 4 and 5, the stepping motor 3 is disposed at the center of the bottom of the storage main body 7a, and dry batteries 5a, 5b,... 5h are disposed along the inner peripheral surface of the storage main body 7a. The control board 2 is arranged above the stepping motor 3 and is fixed to the bracket 8 with screws V2 so as not to move inside the housing body 7a.
With this arrangement, the balance of the center of gravity of the housing 7 is improved, and the strength and durability of the device itself, and the rotational balance when attached to the wheel W and rotated with the wheel W are improved.
[0026]
As shown in FIG. 1, the housing 7 is mounted on the center of the axis of the wheel W via a star-shaped fixing stay 9. At this time, five wheel bolts (not shown) projecting from the wheel W are screwed with a wheel nut 10 having a screw hole 10a in the head. On the other hand, a screw (not shown) is fitted into a screw hole 7e provided on the lower surface of the storage main body 7a through a fixing hole 9a drilled in the fixing stay 9, and the housing 7 is attached to the fixing stay 9. Stick. The fixing stay 9 to which the housing 7 is fixed is screwed into a screw hole 10 a provided in the head of the wheel nut 10 by a bolt 11 inserted through the hole 9 b of the fixing stay 9. Attached to the center of the shaft. Thus, the housing 7 can be easily attached to the wheel W simply by fastening together with the fixing stay 9 to the wheel nut 10, and can be easily removed from the wheel W simply by removing the bolt 11. Also, there is no need to make a dedicated fixing board, and the cost can be reduced accordingly. In the present embodiment, the fixing stay 9 is formed in a star shape, but the shape of the fixing stay 9 is not particularly limited, and may have a hole that matches the position of the wheel nut 10. For example, it may be square or circular.
[0027]
Next, the operation of the tire pressure control device 1 will be described.
When a control signal is transmitted from the external transmitter 6 during traveling of the vehicle, the control signal is transmitted to the stepping motor 3 via the control board 2. The tip 3b of the stepping motor 3 moves forward based on the control signal and retreats after a lapse of a predetermined time, so that the valve pin C1 of the valve C provided at the center of the wheel W is moved for a predetermined time by a predetermined time. By pressing with a stroke (see FIG. 5), a predetermined amount of air is discharged from the tire T into the housing 7 and discharged to the outside through the air holes 7 c and the air holes 9 c formed in the fixing stay 9. Thereby, air can be evacuated by a predetermined amount at a predetermined time while the vehicle is running. Therefore, the accuracy of the performance evaluation test of the air pressure drop monitoring system can be improved.
[0028]
According to the above, the following effects can be obtained in the present embodiment.
Since the control board 2, the stepping motor 3, and the battery 5, which are components mounted on the tire T side, are housed in the cylindrical housing 7, when mounting the housing 7 on the tire T side, Is arranged at the center of the axis of the wheel W, so that the distance from any of the wheel nuts 10 to the housing 7 can be made constant. Therefore, the housing 7 can be attached to the wheel W without interfering with the wheel nut 10.
[0029]
The housing 7 can be attached to the wheel W only by fastening together with the fixing stays 9 that match the number and positions of the wheel nuts 10 and the like, so that the attaching work can be facilitated. Further, even various wheels W having different positions of the wheel nuts 10 can be dealt with simply by replacing the fixing stay 9, so that versatility can be increased. Further, since it is not necessary to remove the wheel W or the tire T for mounting on the wheel W, the mounting operation can be easily performed. In addition, there is no need to make a mounting jig dedicated to mounting, and the cost is economically low.
[0030]
In the housing 7, the heavy stepping motor 3 is arranged at the center, and the battery 5 is arranged around the periphery thereof along the inner peripheral surface of the storage main body 7a. The durability is improved, and the rotation balance when attached to the wheel W and rotated together with the wheel W is improved. Further, by arranging the heavy stepping motor 3 at the center where the centrifugal force is hardly applied, the operation accuracy of the stepping motor 3 can be improved, and the stepping motor 3 can be prevented from falling off in the housing 7 while the vehicle is running.
[0031]
And since the housing | casing 7 is cylindrical and does not have a corner | angular part, the impact resistance of the housing | casing 7 and aging deterioration are equalized, and the intensity | strength and durability of the housing | casing 7 itself improve generally.
[0032]
As described above, an example of a preferred embodiment of the present invention has been described. However, the present invention is not limited to the above-described embodiment, and a design can be appropriately changed without departing from the gist of the present invention.
In the present embodiment, the stepping motor 3 is disposed at the center in the housing 7 and the plurality of dry batteries 5a are disposed along the inner peripheral surface thereof. The stepping motor 3 and the battery formed in a substantially rectangular parallelepiped by bundling a plurality of lithium batteries to be formed can also be arranged in parallel. By doing so, the center of gravity in the housing 7 is balanced, and the batteries are also arranged in a substantially rectangular parallelepiped, so that they can be more easily attached and detached than when they are arranged along the inner peripheral surface.
[0033]
Further, in the present embodiment, the control board 2, the stepping motor 3, and the battery 5 are housed in the housing 7. For example, the air pressure in the tire T is detected in the housing 7. An operation confirmation lamp for detecting whether the pressure sensor or the tire pressure control device is operating normally, a power switch thereof, and the like can be housed so as to be visible.
[0034]
【The invention's effect】
According to the first aspect of the present invention, the housing can be attached to the wheel without interfering with the wheel nut.
[0035]
According to the second aspect of the present invention, the heavy pressing device is disposed at the center of the housing. For this reason, it is easy to balance the center of gravity in the housing, and since the heavy pressing device is disposed at the center where the centrifugal force is not easily applied, it is possible to prevent the housing from falling off during running of the vehicle.
[0036]
According to the third aspect of the invention, in the housing, a plurality of batteries are arranged around a heavy pressing device. For this reason, the housing has a good balance of each part, and is attached to the tire side, so that the rotation balance when rotating together with the tire is improved.
[Brief description of the drawings]
FIG. 1 is a view for explaining assembly of a housing of a tire air pressure control device according to the present embodiment to a tire.
FIG. 2 is an exploded perspective view showing components of the tire air pressure control device according to the embodiment.
FIG. 3 is a perspective view showing a layout inside a housing.
FIG. 4 is a plan view showing a layout in a housing.
FIG. 5 is an exploded perspective view showing a valve pin pressed by a tip of a stepping motor.
FIG. 6 is an exploded perspective view of a tire pressure control device disclosed in Japanese Patent Application No. 2002-315237.
[Explanation of symbols]
1 tire pressure control device 2 control board (tire side receiver)
3 Stepping motor (pressing device)
4 Control wire 5 Battery (power supply means)
6 External transmitter 7 Housing 9 Fixing stay T Tire W Wheel

Claims (3)

A control wire connected to the valve of the tire and having a valve pin of the valve;
A pressing device that releases the air in the tire by pressing the valve pin,
A tire-side receiver that receives a control signal for driving the pressing device from the outside,
Power supply means for receiving a control signal from the tire-side receiver and supplying power to the pressing device,
An external transmitter that transmits the control signal to the tire-side receiver, and a tire pressure control device,
The tire pressure control device, wherein the pressing device, the tire-side receiver, and the power supply unit are housed in a cylindrical housing. The tire pressure control device according to claim 1, wherein the pressing device is disposed at a center of the housing. The tire pressure control device according to claim 2, wherein the power supply unit includes a plurality of batteries, and the batteries are disposed around the pressing device.

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