JP2014122011A - Wheel position distinction system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel position distinction system that associates identification information, which is contained in wheel information sent from a wheel, with the position of the wheel, and more successfully distinguishes the wheel position.SOLUTION: While a wheel position is being distinguished, if a vehicle is halted, and a person alights from or rides on the vehicle or a baggage is loaded or unloaded, a relationship between a detection value of an acceleration sensor and a count value of a wheel speed sensor may be changed (Fig. 11(b)). Distinction of the wheel position is achieved on condition that the relationship between them remains constant. Therefore, if the relationship is changed, the distinction of the wheel position may not be successfully achieved. In contrast, as shown in Fig. 11(c), if a change in the count value occurring when the vehicle is halted is ignored, the relationship between the detection value of the acceleration sensor and the count value of the wheel speed sensor can be held nearly constant between before the vehicle is halted and after the vehicle starts. Eventually, after the vehicle starts, the distinction of the wheel position can be continuously and successfully achieved.

Description

  The present invention relates to a wheel position specifying device that specifies the position of a wheel that transmits wheel information.

  Patent Documents 1 and 2 describe wheel position specifying devices that associate wheel positions with identification information. In the wheel position specifying device described in Patent Documents 1 and 2, a receiver that receives wheel information on a vehicle body is provided with a wheel side unit including an acceleration sensor, an air pressure sensor, a transmitter, and the like in each of a plurality of wheels. A vehicle body side device is provided that includes a wheel speed sensor for detecting the rotational positions of the front, rear, left and right wheels, and a processing unit mainly composed of a computer. In each of the wheel side units, identification information (for example, IDx information) when the wheel side unit reaches a predetermined rotation position of the wheel based on a detection value (acceleration in the rotation direction or centrifugal direction) of the acceleration sensor. A series of wheel information including air pressure information is transmitted. In the vehicle body side device, the detection values of each of the plurality of wheel speed sensors are acquired at the timing when the wheel information including the IDx information is received by the receiver. In the wheel position specifying device described in Patent Document 1, one wheel speed sensor that outputs a detection value with the smallest variation is specified, and the wheel position corresponding to the one wheel speed sensor corresponds to the IDx information. Attached. In the wheel position specifying device described in Patent Document 2, the wheel information is transmitted twice with a predetermined phase while the wheel rotates once from the wheel side unit. One wheel speed sensor that outputs a detection value closest to the interval between the two detection values of the wheel speed sensor is identified.

JP 2010-1222023 A JP 2012-111141 A

  An object of the present invention is to improve a wheel position specifying device, for example, to be able to specify a wheel position better.

Means and effects for solving the problem

In the wheel position specifying device according to the present invention, the position of the wheel side rotation sensor relative to the wheel reaches a predetermined set position based on the detection value of the wheel side rotation sensor from each of the plurality of wheels of the vehicle. At the timing when the wheel information is transmitted and the wheel information including the same identification information is received at the vehicle body of the vehicle, the detection values of the plurality of vehicle-side rotation sensors provided corresponding to each of the plurality of wheels are The wheel position is specified based on each of the plurality of detection values, and when the vehicle is in a set state during the wheel position specification, the wheel position is determined in consideration of the state. The detection value of the vehicle body side rotation sensor is processed based on the specified state.
For example, in one target wheel among a plurality of wheels, target wheel information including IDx identification information is transmitted when the wheel side rotation sensor reaches top dead center, and the target wheel information including IDx is detected in the vehicle body. Each time it is received, the rotation positions {(θa1, θb1, θc1, θd1), (θa2, θb2, θc2, θd2),... Detected. When the detection values of one vehicle body side rotation sensor are substantially the same (θc1≈θc2) and the detection values of the other three vehicle body side rotation sensors are different from each other {(θa1 ≠ θa2), (θb1 ≠ θb2), ( θd1 ≠ θd2)}, the vehicle body side rotation sensor that outputs the detection values (θc1, θc2) is identified as the vehicle body side rotation sensor that detects the rotation position of the target wheel, and the identification information IDx and the vehicle body side rotation sensor are identified. Is associated with the position of the wheel (the position of the target wheel).
This wheel position is identified by (a) the rotational angular velocities of the wheels provided on the vehicle differing from each other, and (b) between the detection value of the wheel side rotation sensor and the detection value of the vehicle body side rotation sensor. It is assumed that a certain relationship is established. Based on the detection value of the wheel side rotation sensor, the relative phase with respect to the wheel of the wheel side rotation sensor is determined, and the detection value of the vehicle body side rotation sensor represents the rotation angle from the reference position of the wheel. is there.
From the above circumstances, for example, based on the detection values of each of the vehicle body side rotation sensors, it may be specified that the vehicle body side rotation sensor that outputs the detection value with the smallest variation corresponds to the target wheel. it can. Specifically, a plurality of detection values of each of the plurality of vehicle body side rotation sensors are obtained, and it is determined whether or not each of the plurality of detection values is within the setting range. Vehicle-side rotation sensors that output detection values that are not in the range are excluded from the identification candidates, and the last remaining vehicle-side rotation sensor is identified as corresponding to the target wheel, or (2) the detection value within the set range For example, the vehicle body side rotation sensor that outputs the detection value having the largest number can be identified as corresponding to the target wheel.
On the other hand, the vehicle may stop while the wheel position is specified. Since the wheel information is not transmitted from the wheel side device while the vehicle is stopped, the detection value of the vehicle body side rotation sensor is not acquired for specifying the wheel position. Therefore, if the vehicle stops while the wheel position is specified, the wheel position specification is interrupted and the wheel position is specified again after starting, that is, the above-described acquired vehicle body acquired before the vehicle stops. Clear the information such as the detection value of the side rotation sensor, the determination result of whether the detection value is within the setting range, the vehicle side rotation sensor excluded from the specific candidate, the number of detection values within the setting range, etc. The position can be specified from the beginning. However, if the specification of the wheel position is interrupted each time the vehicle stops, it is not desirable because it takes a long time to specify the wheel position particularly in the case of traffic jams. Therefore, even if the vehicle stops while the wheel position is specified, the above-mentioned information acquired before the vehicle stops is maintained after starting, and the wheel position is continuously specified (the detection value of the vehicle side rotation sensor). Acquisition, determination of whether it is within the setting range, counting of the number of detection values within the setting range, exclusion from specific candidates, etc.).
However, if a person gets on or off or loads or unloads a vehicle while the vehicle is stopped, the vehicle body and the wheel are moved relative to each other, and the detection value of the vehicle body side rotation sensor is detected even though the wheel is not rotating. May be changed, and the relationship between the detection value of the acceleration sensor and the detection value of the vehicle body side rotation sensor may change. For this reason, when the vehicle is started after stopping and the wheel position is continuously specified, the vehicle body side rotation sensor may not be properly specified.
In addition, when the vehicle body side rotation sensor is of a type in which the count value as the detection value is increased even if the wheel is rotated in the forward direction or the reverse direction, when the vehicle moves backward, The relationship between the detection value of the wheel side rotation sensor and the detection value of the vehicle body side rotation sensor changes. For this reason, if the wheel position is specified while the vehicle is moving backward or moving forward after moving backward, the vehicle body side rotation sensor may not be properly specified.
On the other hand, in the wheel position specifying device according to the present invention, for example, when the vehicle is in a stopped state, even if the detection value of the vehicle body side rotation sensor is changed, the change is ignored, For example, the count value can be decreased when the vehicle is in the reverse state. It is also possible to acquire the change amount of the detected value while the vehicle is stopped, and to specify the wheel position after the start in consideration of the change amount. As a result, it is possible to suppress the inconvenience that the wheel position is not well identified due to a change in the relationship between the detection value of the acceleration sensor and the detection value of the vehicle body side rotation sensor. Further, even if the vehicle stops while the wheel position is being specified, the wheel position is continuously specified after the start of the vehicle. Therefore, it is possible to favorably avoid an increase in the time required for specifying the wheel position.
“While identifying the wheel position” refers to the period from when the identification of the wheel position is started until the identification information is associated with the wheel position. Specifically, in order to associate one piece of identification information with a wheel position, acquisition of the detection value of the vehicle body side rotation sensor, determination of whether or not it is within the setting range, and counting of the number of detection values within the setting range A series of operations such as determination of the vehicle body side rotation sensor excluded from the specific candidates has started, but the wheel position is not associated with the identification information. “Continue specifying wheel position” means that one or more of the acquired detection value, determination result, count value of the vehicle number, determination of the vehicle body side rotation sensor excluded from the specific candidates, etc. are cleared. The wheel position is specified based on these count values, determination of the excluded vehicle body side rotation sensor, and the like.

Patentable invention

In the following, the invention recognized as being able to be claimed in the present application will be described.
(1) Provided on each of a plurality of wheels of the vehicle, (a) a wheel side rotation sensor that detects the rotation position of the wheel, and (b) the wheel side rotation determined based on a detection value of the wheel side rotation sensor. A wheel-side device comprising: a transmitter that transmits at least wheel information including identification information set for the wheel at a timing when the position of the sensor with respect to the wheel reaches a predetermined position;
(I) a receiver that receives wheel information transmitted from each of the plurality of wheel-side devices; and (ii) a rotational position of the wheel corresponding to each of the plurality of wheels. And (iii) target wheel information which is wheel information transmitted from the target wheel side device which is one of the plurality of wheel side devices by the receiver. Is received by each of the vehicle body side rotation sensors, and based on each of the detected values, the target wheel that is the wheel that transmitted the target wheel information is detected. A wheel position specifying device including a vehicle body side device including a wheel position specifying unit that specifies one corresponding vehicle body side rotation sensor and associates the identification information included in the target wheel information with the position of the target wheel. There,
When the vehicle is in a set state during execution of the wheel position specifying unit, the wheel position specifying unit processes at least one detection value of the plurality of vehicle body side rotation sensors according to the state. A wheel position specifying device including a detection value processing unit.
When one receiver is provided on the vehicle body, two or three receivers may be provided, but in any case, the receiver is provided in common for a plurality of wheel side devices.
The vehicle body side rotation sensor is provided at a position corresponding to each of the plurality of wheels of the vehicle body. The vehicle body side rotation sensor detects the rotation angle from the reference position of the wheel, and detects the relative rotation angle at which the reference position is variable even if it detects the absolute rotation angle at which the reference position is fixed. You may do. In the case of detecting the relative rotation angle, the reference position may be the same as long as the wheel position is specified at least once.
(2) The setting state includes a state in which at least one detection value of the plurality of vehicle body side rotation sensors changes when a corresponding wheel is not rotating, and a state in which the detection value may change. The wheel position specifying device according to (1), which is either one.
(3) There is a possibility that at least one of the plurality of wheels and the vehicle body are relatively moved and the relative movement is not caused by the rotation of the plurality of wheels. The wheel position specifying device according to (1) or (2), which is one of states.
If the wheel and the vehicle body are moved relative to each other without causing the rotation of the wheel, the detection value of the vehicle body side rotation sensor is changed, and the relationship may change. For example, there is a possibility that the vehicle body and the wheel may be moved relative to each other when there is a person getting on / off, lifting / unloading a baggage, when a crosswind is received, or when the shift position is switched while the vehicle is stopped. .
(4) The set state includes: (a) a state where the vehicle is stopped; (b) a state where at least one of a plurality of opening / closing bodies provided in the vehicle is open; The wheel position specifying device according to any one of (1) to (3), wherein the wheel position specifying device includes one or more of a state in which the vehicle is moving backward.
The body side rotation sensor is of the type (c-1) where the count value as a detection value is increased when the wheel is rotating in the forward direction and the count value is decreased when the wheel is rotating in the reverse direction (C-2) There is a type in which the count value is increased regardless of whether the wheel rotates in the forward direction or in the reverse direction. In this case, it is desirable to reduce the count value of the vehicle body side rotation sensor.
(5) The detection value processing unit changes the detection values of some of the plurality of vehicle body side rotation sensors, and the remaining vehicle body side rotation sensors excluding the some of the vehicle body side rotation sensors. The wheel position identification according to any one of (1) to (4), further including a stop state determination unit that determines that the vehicle is in the stop state as the set state when the detected value of the vehicle does not change apparatus.
When a plurality of vehicle body side rotation sensors include those whose detection values change and those whose detection values do not change, the vehicle is in a stopped state and the vehicle side rotation sensor is caused by relative movement between the wheels and the vehicle body. It is determined that the detected value has changed and the relationship has changed.

(6) The detection value processing unit processes at least one detection value of the plurality of vehicle body side rotation sensors, thereby detecting each of the detection values of the at least one vehicle body side rotation sensor and the corresponding ones. The wheel position specifying device according to any one of (1) to (5), including a relationship change suppression unit that suppresses a change in relationship with each of the detection values of the wheel side rotation sensor.
It is preferable that the relationship between the detection value of the vehicle body side rotation sensor and the detection value of the wheel side rotation sensor is kept substantially constant by processing the detection value.
(7) The detection value processing unit is (i) a change ignoring unit that ignores a change in at least one of the plurality of wheel side rotation sensors, and (ii) the at least one detection value is constant. The detection value holding unit, and (iii) one or more of a countdown unit that decreases a count value that is a detection value of the plurality of wheel side rotation sensors. The wheel position specifying device according to any one of the above.
(i) In the change ignoring section, the presence or absence of a change in the detected value is detected, and even if there is a change, it is considered that there has been no change. (ii) The detection value holding unit may or may not detect the presence or absence of a change in the detection value. It is assumed that it is constant regardless of whether or not the detected value changes. (iii) When the count value is increased in the forward rotation of the wheel, it is desirable that the count value be decreased in the reverse rotation of the wheel.
(8) The detection value processing unit acquires each change in at least one detection value when at least one detection value of the plurality of vehicle body side rotation sensors changes in the stop state of the vehicle. A change-based wheel position specifying unit that specifies the wheel position in consideration of a change in each of the at least one detection value acquired by the change acquisition unit. The wheel position specifying device according to any one of (1) to (7).
The change in detection value includes the direction of change, the amount of change, and the like.
For example, based on the change in the detection value of the vehicle body side rotation sensor while the vehicle is stopped, the relationship after the change can be acquired. It can be considered that the relationship has shifted according to the change in the detection value.For example, the setting range after the change is acquired based on the relationship after the change so that the wheel position can be specified. it can.
Further, when the detection value of the vehicle body side rotation sensor changes while the vehicle is stopped, it can be considered that the error in the detection value of the vehicle body side rotation sensor has increased accordingly. In this case, the setting range can be expanded based on the change in the detected value, and the wheel position can be specified based on the expanded setting range.
Note that even if the setting range is changed (including moving or expanding the setting range) individually for each of the plurality of vehicle body side rotation sensors, it is common to the plurality of vehicle body side rotation sensors (similarly). You may go. For example, it can be similarly performed based on the maximum value of the change amount of each detected value of the plurality of vehicle body side rotation sensors, the average value of the change amount, and the like.
Further, the amount of change of the setting range (including the shift amount, the enlargement amount, etc.) can be made larger when the detected value change amount is large than when it is small.
Furthermore, when the change amount of the detected value is large, the wheel position is specified in consideration of the change amount, and when the change amount is small, the wheel position is specified without considering the change amount. it can.

(9) When the detected value processing unit is at least one of a case where the vehicle is in a stopped state and a case where at least one of a plurality of opening / closing bodies provided in the vehicle is in an open state The wheel position specifying device according to any one of items (1) to (8), further including a detection value holding unit such as during stop, in which detection values of the plurality of vehicle-side rotation sensors are constant.
(10) When the detection value processing unit changes a part of detection values of the plurality of vehicle body side rotation sensors during a predetermined set time and the remaining detection values do not change, the vehicle The wheel according to any one of items (1) to (9), further including a during-stop change ignoring unit that ignores a change in the detected value of each of the part of the vehicle-side rotation sensors. Positioning device.
(11) When the detected value processing unit changes at least one of the detected values of the plurality of vehicle body side rotation sensors when the vehicle is in a stopped state, each of the detected values A change amount acquisition unit for acquiring a change amount, wherein the wheel position specifying unit determines whether or not (i) the detection values of the plurality of vehicle body side rotation sensors are within a set range, respectively. A variation acquisition unit; and (ii) (ii-1) a setting range individual changing unit that individually changes the setting range based on a change amount of a detection value of the vehicle body side rotation sensor corresponding thereto (ii-2) A setting range changing unit including at least one of a setting range common changing unit that similarly changes the setting range based on at least one of the change amounts of the at least one detection value (1) The wheel position specifying device according to any one of items 10 to 10.
The setting range can be a range determined based on the degree of variation, a range determined based on a detection value error, or the like.
(12) When the detection value processing unit detects that the vehicle is in a stopped state, (a) the detection values of some of the plurality of vehicle body side rotation sensors change. A change ignoring unit for ignoring a change in detection values of some of the vehicle body side rotation sensors when detection values of the remaining vehicle body side rotation sensors do not change, and (b) detection values of the plurality of vehicle body side rotation sensors. The wheel position specifying device according to any one of the items (1) to (11), further including a change amount acquisition unit that acquires the change amounts of the plurality of detection values when all of these change.
When the detected values of some vehicle body side rotation sensors change and the detected values of the remaining vehicle body side rotation sensors do not change when it is detected that the vehicle is stopped, some vehicle body side rotation sensors The detected value is changed due to the relative movement between the vehicle body and the wheel, and it can be determined that the change is not due to the rotation of the wheel. However, even when it is detected that the vehicle is in a stopped state, if all the detected values of the plurality of vehicle body side rotation sensors have changed, the change may be caused by the rotation of the wheel. Therefore, in the latter case, it is difficult to cause inconvenience caused by changing the relationship by changing the setting range. In addition, since the change in the detected value is not ignored, even if the change is caused by the rotation of the wheel, the wheel position can be identified satisfactorily.

(13) The wheel side rotation sensor is an acceleration sensor that detects acceleration acting on the wheel side rotation sensor, and the position of the acceleration sensor determined by the transmitter based on a detection value of the acceleration sensor is predetermined. The wheel position specifying device according to any one of (1) to (12), wherein the wheel information is transmitted when the position is reached.
The detection value of the acceleration sensor changes periodically with the rotation of the wheel. For example, the wheel information may be transmitted at a timing determined by the detection value of the acceleration sensor, or may be transmitted at a timing determined by the differential value (change in the detection value). Specifically, the acceleration sensor detection value is transmitted at a timing when it reaches a set value (for example, it can be set to 0 or 1G), or the detection value of the acceleration sensor reaches a peak value. It is possible to transmit at a timing (for example, a timing at which a maximum value or a minimum value is reached). The wheel information is transmitted a predetermined number of times (for example, once or twice) while the wheel rotates once.
(14) The vehicle body side rotation sensor includes a detection unit facing an outer peripheral portion of a rotating body provided to be rotatable integrally with the wheel, and the rotation based on a change in electrical properties in the detection unit. The rotation angle of the body is detected, and the outer peripheral portion of the rotating body periodically changes the electrical properties of the detecting section as the rotating body rotates. The wheel position specifying device according to any one of the items).
The rotating body may have a gear shape in which concave portions and convex portions are alternately positioned on the outer peripheral portion, or may be a magnetic rotor in which N poles and S poles appear alternately.
(15) The wheel position specifying unit includes a sensor specifying unit that specifies a vehicle body side rotation sensor that outputs the detection value with the smallest variation in the detection value, according to any one of (1) to (14). Wheel positioning device.
(16) Except for a vehicle-side rotation sensor that obtains whether or not (a) each of the detection values is within the first setting range, and outputs the detection value that is out of the first setting range. A first specifying unit that specifies that the last remaining vehicle-side rotation sensor is the vehicle-side rotation sensor corresponding to the target wheel; and (b) the largest number of detection values within the second setting range. Any one of the items (1) to (15) includes at least one of the second specifying unit that specifies the vehicle-side rotation sensor that outputs the detection value as the vehicle-side rotation sensor corresponding to the target wheel. The wheel position specifying device described.
The first setting range and the second setting range may be the same or different.

(17) While the vehicle body side device is in a stop state of the vehicle, a maximum value of a change amount of at least one of the plurality of vehicle body side rotation sensors is equal to or greater than a predetermined set value. In this case, the wheel position specifying device according to any one of (1) to (16), including a wheel position specifying interrupting unit that interrupts specification of the wheel position.
For example, if the vehicle stops while the wheel position is being specified and the ignition switch is turned OFF, the wheel position specification is interrupted, and if the ignition switch remains ON, the vehicle starts. Then, the wheel position can be specified continuously. However, if the detection value of the vehicle body side rotation sensor changes without being caused by the rotation of the wheel while the vehicle is stopped, it is difficult to continuously specify the wheel position satisfactorily. In this case, if the specification of the wheel position is always interrupted, the specification of the wheel position is not desired to be delayed, but if the influence of the change in the detected value on the specification of the wheel position is small, the specification of the wheel position is not possible. It can be done continuously. Therefore, the continuous determination of the wheel position is interrupted only when the maximum value of the change amount is large and the influence on the specification of the wheel position is large.
(18) provided on each of a plurality of wheels of the vehicle, (a) a wheel-side rotation sensor for detecting a rotation position of the wheel, and (b) the wheel-side rotation determined based on a detection value of the wheel-side rotation sensor. A wheel-side device comprising: a transmitter that transmits at least wheel information including identification information set for the wheel at a timing when the position of the sensor with respect to the wheel reaches a predetermined position;
(I) a receiver that receives wheel information transmitted from each of the plurality of wheel-side devices; and (ii) a rotational position of the wheel corresponding to each of the plurality of wheels. And (iii) target wheel information which is wheel information transmitted from the target wheel side device which is one of the plurality of wheel side devices by the receiver. Is received by each of the vehicle body side rotation sensors, and based on each of the detected values, the target wheel that is the wheel that transmitted the target wheel information is detected. A wheel position specifying device including a vehicle body side device including a wheel position specifying unit that specifies one corresponding vehicle body side rotation sensor and associates the identification information included in the target wheel information with the position of the target wheel. There,
When the vehicle is in a set state during execution of the wheel position specifying unit, the wheel position specifying unit continuously specifies the wheel position in consideration of the state of the vehicle. The wheel position specifying device characterized by including a part.
“Continue to identify the wheel position in consideration of the vehicle status” includes (a) changing the setting range when the vehicle status is set, or interrupting the wheel position specification. (B) When the state of the vehicle is in the set state and the change in the detected value is large, the setting range is changed, the detected value is corrected, and the like. The wheel position is specified in a manner different from the case where the vehicle state is not set.
The technical features described in any one of the items (1) to (17) can be adopted for the wheel position specifying device described in this item.

It is a conceptual diagram which shows the whole wheel state acquisition apparatus containing the wheel position specific apparatus which concerns on Example 1 of this invention. It is a figure which shows notionally the structure of the wheel side apparatus contained in the said wheel state acquisition apparatus, and a vehicle body side apparatus. It is a front view of the wheel from which a state is detected by the said wheel state acquisition apparatus. It is a figure which shows the timing which wheel information is transmitted from the said wheel. It is a figure which shows the said wheel information notionally. It is a map showing the wheel position acquisition table memorize | stored in the memory | storage part of TPMS ECU of the said wheel state acquisition apparatus. It is a flowchart showing the wheel state acquisition program memorize | stored in the memory | storage part of the said TPMS ECU. It is a flowchart showing the wheel position specific program memorize | stored in the memory | storage part of the said TPMS ECU. It is a flowchart showing the detected value processing program memorize | stored in the memory | storage part of the said TPMS ECU. It is a figure which shows the state by which a wheel position is specified by execution of the said wheel position specific program. (a), (b) It is a figure which shows the relationship between the detected value of the wheel side rotation sensor in the conventional wheel position specific device, and the count value which is a detected value of the vehicle body side rotation sensor. (c) It is a figure which shows the relationship between the detection value of a wheel side rotation sensor and the processing value of the detection value of a vehicle body side rotation sensor when the detection value processing program in the wheel position specific | specification apparatus in Example 1 is performed. It is a flowchart showing the (a) count prohibition flag set program memorize | stored in the memory | storage part of TPMS ECU of the wheel position specific apparatus which concerns on Example 2 of this invention. (b) It is a flowchart showing a detection value processing program. (a), (b) It is a figure which shows the relationship between the detected value of the wheel side rotation sensor in the conventional wheel position specific device, and the count value which is a detected value of the vehicle body side rotation sensor. (c) It is a figure which shows the relationship between the detection value of a wheel side rotation sensor and the processing value of the detection value of a vehicle body side rotation sensor when the detection value processing program in the wheel position specific | specification apparatus in Example 2 is performed. It is a flowchart showing the detection value processing program memorize | stored in the memory | storage part of TPMS ECU of the wheel position specific apparatus which concerns on Example 3 of this invention. It is a flowchart showing the detection value processing program memorize | stored in the memory | storage part of TPMS ECU of the wheel position specific apparatus which concerns on Example 4 of this invention. It is a flowchart showing the wheel position specific program memorize | stored in the memory | storage part of the said TPMS ECU. It is a figure which shows the state by which a wheel position is specified by execution of the said wheel position specific program. It is a flowchart showing the detection value processing program memorize | stored in the memory | storage part of TPMS ECU of the wheel position specific apparatus which concerns on Example 5 of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION

  Hereinafter, a wheel state acquisition device according to an embodiment of the present invention will be described in detail with reference to the drawings. In this wheel state acquisition apparatus, the wheel position specifying device which is one embodiment of the present invention is included.

As shown in FIG. 1, in this vehicle, the front and rear, left and right wheels 10FL, FR, RL, RR are provided with wheel side units 12FL, FR, RL, RR as wheel side devices, respectively. A vehicle body side device 16 is provided.
As shown in FIG. 2, the vehicle body side device 16 is a vehicle side rotation sensor provided corresponding to each of the receiver 22, the display 24, the reset switch 25, the front and rear wheels 10 FL, FR, RL, and RR. Wheel speed sensors 26FL, FR, RL, RR, a shift position sensor 27, a door opening / closing detection device 28, a TPMS (Tire Pressure Monitoring System) ECU 30, mainly a computer, a brake ECU 32, a navigation ECU (hereinafter abbreviated as a navigation ECU). 34) and the like.
Hereinafter, when it is necessary to distinguish the wheel 10, the wheel side device 12, the wheel speed sensor 26, and the like by the wheel positions FL, FR, RL, and RR, they are described with reference numerals representing the wheel positions. When there is no symbol, when referring generically, etc., there is a case where it is described without a symbol indicating the wheel position.

As shown in FIG. 2, each of the wheel side units 12 includes an air pressure sensor 40 as a wheel state sensor, an acceleration sensor 42 as a wheel side rotation sensor, a transmitter 44, and the like.
As shown in FIG. 3, the acceleration sensor 42 detects acceleration acting on itself (sensor). The acceleration toward the rotation center of the wheel 10 is +, and the acceleration in the opposite direction (the centrifugal direction of the wheel 10) is It is provided in a state of −. Since the acceleration G and the centrifugal force F caused by gravity act on the rotating wheel 10, the detection value Y of the acceleration sensor 42 is an expression when the angle θ is determined with reference to a line parallel to the road surface. Y = -F-Gsinθ
It is represented by Since the centrifugal force F is constant when the wheel 10 is rotating at a constant speed, the detection value Y changes as shown in FIG.

In the present embodiment, the wheel information 50 changes when the acceleration sensor 42 (wheel side unit 12) reaches top dead center, that is, the detection value of the acceleration sensor 42 changes from an increasing tendency to a decreasing tendency (differential value). Is transmitted at a timing at which the value becomes 0 from a positive value. Even if braking force or driving force is applied to the wheel 10, the acceleration value becomes maximum when the wheel side unit 12 reaches the top dead center. At the timing when the unit 12 reaches the top dead center, the wheel information 50 is transmitted wirelessly once during one rotation of the wheel 10.
Note that the timing for transmitting the wheel information 50 may be determined in any way. For example, the wheel information 50 may be transmitted at the timing when the bottom dead center or a position rotated by 90 ° from the top dead center is reached. Further, it may be transmitted twice or more during one rotation of the wheel 10. Furthermore, the acceleration sensor 42 can also detect acceleration in the rotational direction.
As shown in FIG. 5, the wheel information 50 is a series of information including start information 52, identification information 53, air pressure information 54, end information 55, and the like. The identification information 53 is a value individually determined for the wheel side units 12FL, FR, RL, RR.

One receiver 22 is provided in common for the four wheel side units 12FL, FR, RL, RR on the front, rear, left, and right, and wheel information transmitted wirelessly from each of the wheel side units 12FL, FR, RL, RR. 50 is received.
The display 24 displays the air pressure value represented by the air pressure information 54 included in the wheel information 50 in association with the wheel position. When the air pressure value P is lower than the normal determination threshold value Pth, the air pressure value P is displayed in a mode different from that when the air pressure value P is higher than the normal determination threshold value Pth.
The reset switch 25 is a switch that is determined to be manually operated when tire replacement (including tire rotation, the same applies hereinafter) or the like is performed. It becomes a specific trigger.
The shift position sensor 27 can detect the shift position of the transmission or can detect the operation position of the shift operation member.
The door open / close detection device 28 detects door open / close states as a plurality of opening / closing bodies provided in the vehicle, and includes a door courtesy lamp switch and the like provided in each of the plurality of opening / closing bodies. The plurality of opening / closing bodies includes a trunk room opening / closing body (luggage door).

Wheel speed sensors (rotational angular velocity sensors) 26FL, FR, RL, RR are positions corresponding to the wheels 10FL, FR, RL, RR of the vehicle body 14, that is, as shown in FIG. Each of the rotors 56 is provided in a fixed manner in a state of facing the teeth 58 provided in the circumferential direction on the outer periphery of the rotor 56 that is integrally rotatable. In each of the wheel speed sensors 26FL, FR, RL, and RR, an electrical signal is transmitted along with the passage of a tooth 58 (strictly speaking, an edge that is a boundary between the convex and concave portions of the tooth 58) facing the sensor unit. Is changed and the number of changes in the electrical signal is counted. The count value of the number of edges that have passed the position facing the sensor unit from the reference position of the rotor 56 is the detection value, and the rotation angle from the reference position can be found based on the count value as the detection value. In this embodiment, 48 teeth 58 are formed on the outer periphery of the rotor 56, and the count value when the wheel 10 makes one revolution is Ns (48 × 2 = 96). As shown in FIG. 11A, the count value is returned to 0 when it reaches Ns (96). The reference position may be fixed or variable. For example, the position when the ignition switch is turned from OFF to ON (the tooth 58 at the position facing the sensor unit is counted). Corresponding to the reference tooth).
Further, as shown in FIGS. 4 and 11 (a), since the rotor 56 is provided so as to be rotatable integrally with the wheel 10, the detected value of the acceleration sensor 42 changes as the rotor 56 rotates, while the wheel speed. The count value of the sensor 26 is changed. From this, it can be seen that a predetermined relationship is established between the count value of the wheel speed sensor 26 and the detection value of the acceleration sensor 42.
The wheel speed sensor 26 is connected to the brake ECU 32, and the count value acquired in the brake ECU 32 is supplied to the TPMS ECU 30.
In the present embodiment, the number of teeth 58 provided on the rotor 56 is 48, but the number of teeth 58 is not limited.
The rotor 56 can also be a magnetic rotor. In that case, rubber powder is provided on the outer periphery of the rotor 56 in a state where N poles and S poles are alternately arranged in the circumferential direction.

  The TPMS ECU 30 has a computer as a main body, and processes the wheel information 50 received by the receiver 22 to acquire an air pressure value and specify a wheel position. The storage unit 64 includes a wheel position acquisition table represented by the map of FIG. 6, a wheel state acquisition program represented by the flowchart of FIG. 7, a wheel position identification program represented by the flowchart of FIG. 8, and a flowchart of FIG. A plurality of programs such as the detected value processing program represented are stored.

The operation of the wheel state acquisition device configured as described above will be described.
<Acquisition of wheel state>
The wheel state acquisition program represented by the flowchart of FIG. 7 is executed at predetermined time intervals.
In step 1 (hereinafter abbreviated as S1. The same applies to other steps), it is determined whether or not the wheel information 50 is received by the receiver 22. If received, the identification information 53 and the air pressure information 54 included in the wheel information 50 are read in S2, and in S3, the identification information 53 and the wheel position acquisition table represented by the map of FIG. The position of the wheel 10 to which the wheel information 50 is transmitted is acquired. In S4, it is determined whether or not the air pressure value P represented by the air pressure information 54 is lower than the normal determination threshold value Pth. If it is equal to or greater than the normal determination threshold value Pth, it is determined that the air pressure is normal, and the air pressure value P is displayed on the display 24 in association with the wheel position in S5. On the other hand, if the air pressure value P is lower than the normal determination threshold value Pth, it is displayed in S6 that the air pressure value P and the air pressure value are abnormal in association with the wheel position.

<Identification of wheel position>
For example, a case will be described in which the target wheel which is one of the front, rear, left and right four wheels 10FL, FR, RL, RR is the right front wheel 10FR. As described above, at the timing when the detected value of the acceleration sensor 42FR in the right front wheel 10FR changes from the increasing tendency to the decreasing tendency (timing when the differential value becomes 0 from the positive value), that is, the wheel side unit 12FR is dead. Wheel information 50FR is transmitted at the timing when the point is reached.
The rotation position of the wheel 10 determined based on the detection value of the acceleration sensor 42 {represented by the rotation phase (rotation angle) from the reference position of the wheel 10. Based on both the detected value and the differential value of the acceleration sensor 42, the rotation angle of the wheel 10 from the reference position (the position of the acceleration sensor 42 in the rotation direction with respect to the wheel 10) is determined} and the count value of the wheel speed sensor 26 Since the wheel information 50FR is transmitted, that is, the count value of the wheel speed sensor 26FR acquired at the timing when the wheel information 50FR is received by the receiver 22 should always be the same. It is.
In contrast, the count values of the other wheels 10FL, RL, RR are usually not always the same. The rotational angular velocities of the front, rear, left and right wheels 10FL, FR, RL, RR are usually different. Further, a difference in rotational speed between the left and right sides occurs during turning, and some wheels slip during braking and driving. Furthermore, even during constant speed and straight traveling, the rotational angular velocity varies depending on the dynamic load radius.

In this embodiment, therefore, the count values of the wheel speed sensors 26FL, FR, RL, RR are acquired while the vehicle is running, that is, while the wheels 10FL, FR, RL, RR are rotating. The wheel speed sensor 26 that outputs the count value with the smallest variation is identified. Further, when the acceleration sensor 42 outputs a detection value when the rotation speed of the wheel 10 exceeds the set rotation speed (when the centrifugal force exceeds the set value), the traveling speed of the vehicle is smaller than the set speed. In this case, the count value of the wheel speed sensor 26 is not acquired. Then, as shown in FIG. 10, it is determined whether the count value (a count processing value is used as will be described later) is within the set range SRc, and the wheel speed sensor that outputs the count value outside the set range SRc. 26 is excluded from the specific candidates, and when the count value determined to be within the set range SRc becomes one, the wheel speed sensor 26 that outputs the count value is specified.
The count value setting range SRc is determined based on the rotation angle setting range SRθ and the count value during one rotation is 96.
SRc = SRθ · 96 / 2π
The rotation angle setting range SRθ is determined based on the error of the detection value of the acceleration sensor 42, the degree of variation, and the like.
Note that the upper limit value and lower limit value of the setting range may or may not be specified. For example, it is determined based on the detection value of the wheel speed sensor 26 detected for the first time in specifying the wheel position, and it is determined whether or not the second and subsequent detection values exist between the upper limit value and the lower limit value. In this case, it is possible to determine whether or not a plurality of detection values are within the setting range without determining the upper limit value and the lower limit value of the setting range based on the first detection value or the like. Good. In the latter case, it can be considered that the upper limit value and the lower limit value are determined by a plurality of detection values.

For example, at the timing when the wheel information 50 including the identification information (IDa) 53 is received by the receiver 22, the count values of the wheel speed sensors 26FL, FR, RL, RR are acquired (Ca1, Cb1, Cc1, Cd1). Next, the count values of the wheel speed sensors 26FL, FR, RL, RR are acquired at the timing when the wheel information 50a including IDa is received (Ca2, Cb2, Cc2, Cd2). In this case, when Ca1 and Ca2, Cb1 and Cb2, Cc1 and Cc2 are within the set range SRc, and Cd1 and Cd2 are not within the set range SRc, the wheel speed sensor 26 that outputs Cd1 and Cd2 (for example, , RR) are excluded from the specific candidates.
Next, regarding the obtained count values (Ca3, Cb3, Cc3, Cd3) of the wheel speed sensors 26FL, FR, RL, RR, Ca3 is within the set range SRc determined by Ca1, Ca2, and Cb3 is Cb1, Cb2. However, if Cc3 is not within the setting range SRc determined by Cc1 and Cc2, the wheel speed sensor 26 (for example, FL) that outputs Cc1, Cc2, and Cc3 is excluded.
Then, regarding the count values (Ca4, Cb4, Cc4, Cd4) of the wheel speed sensors 26FL, FR, RL, RR acquired next, Ca4 is within the set range SRc determined by Ca1 to Ca3, and Cb4 is Cb1 to Cb3. If it is not within the set range SRc determined by, the wheel speed sensor 26 (for example, RL) that outputs Cb1 to Cb4 is excluded. What remains is one wheel speed sensor 26FR that outputs the count values Ca1 to Ca4. As a result, it can be specified that the wheel information 50a is transmitted from the wheel side unit 12FR of the wheel speed sensor 26FR, the identification information IDa and the right front wheel 10FR are associated, and the wheel position of the identification information IDa is Identified.

However, during the specification of the wheel position, the relationship between the count value of the wheel speed sensor 26 and the detection value of the acceleration sensor 42 may change. The specification of the wheel position refers to a period from the start of the specification of the wheel position until the correspondence between the identification information and the wheel position, such as when the reset switch 25 is turned on. Specifically, in order to associate one piece of identification information with a wheel position, acquisition of a detection value of the wheel speed sensor 26, determination of whether it is within the set range, determination of the wheel speed sensor 26 excluded from the specific candidate A state in which the wheel position is not associated with the identification information is started.
As shown in FIG. 11A, when the vehicle is stopped while the wheel position is being specified, the wheel 10 and the vehicle body 14 are not relatively moved while the vehicle is in the stopped state (relative movement is not performed). When the vehicle is small, the relationship between the detection value of the acceleration sensor 42 and the count value of the wheel speed sensor 26 is kept substantially constant, and these relationships are substantially the same even after the vehicle starts.
On the other hand, as shown in FIG. 11 (b), the vehicle body moves due to the getting on and off of a person while the vehicle is stopped, the lifting and lowering of the load, etc., so that the wheel speed sensor 26 and the wheel fixed to the vehicle body 14 are 10 may be moved relative to each other (the relative positional relationship changes), and the count value may be changed. As a result, the relationship between the detection value of the acceleration sensor 42 and the count value of the wheel speed sensor 26 changes, and there is a possibility that the wheel position cannot be specified satisfactorily.
FIG. 11 shows the state of change in the detected value of the acceleration sensor 42 accompanying the rotation of the wheel 10 and the state of change in the count value of the wheel speed sensor 26. Strictly speaking, the rotational speed of the wheel decreases immediately before the vehicle stops and increases after the vehicle starts, but such a change in rotational speed is not taken into consideration. The same applies to FIG.

Therefore, in the present embodiment, whether or not the change in the count value of the wheel speed sensor 26 is caused by relative movement between the wheel 10 and the vehicle body 14 (whether it is not caused by the rotation of the wheel 10 or caused by the rotation of the wheel 10). ) Is determined, and if it is determined that it is caused by the relative movement between the wheel 10 and the vehicle body 14, the change in the count value of the wheel speed sensor 26 is ignored (there is no change).
Specifically, the count value of each of the four wheel speed sensors 26 is acquired during the set time, and when both the wheel speed sensor 26 whose count value has changed and the wheel speed sensor 26 that has not changed exist. For example, the vehicle body 14 is moved due to a person getting on and off, lifting or unloading a load, and the wheel 10 and the vehicle body 14 are relatively moved, and thereby the count values of some wheel speed sensors 26 are changed. it is conceivable that. In other words, when both the wheel speed sensor 26 in which the count value has changed and the wheel speed sensor 26 in which the count value has not changed exist, it is determined that the change is not caused by the rotation of the wheel 10. Further, since the change in the count value of the wheel speed sensor 26 is ignored, the count processing value (processing value of the detection value) Ci * described later is used in specifying the wheel position after the vehicle has started (i). = A, b, c, d). The count processing value after the start is a value shifted by an amount of change in which the count value Ci supplied from the brake ECU 32 is ignored.

The wheel position specifying program shown in the flowchart of FIG. 8 is executed, for example, when a position specifying start condition is satisfied, and is started, for example, when the reset switch 34 is manually operated.
In a present Example, the case where the wheel position of identification information IDa is specified is demonstrated. The same applies to the case where the wheel position of other identification information is specified.
In S10, it is determined whether or not the vehicle is in a traveling state. If the vehicle is in the traveling state, it is determined in S11 whether or not the wheel information 50a including the identification information IDa to be specified has been received. If received, in S12, count processing values Ci * described later are respectively acquired. In S13, it is determined whether or not the count process value Ci * is within the set range SRc, and the wheel speed sensor 26 that has output the count process value not within the set range SRc is excluded from the specific candidates. In S14, it is determined whether or not the count processing value determined to be within the set range SRc is one (one wheel speed sensor 26 remaining as a specific candidate). S10 to 14 are repeatedly executed, and when the number of wheel speed sensors 26 (count processing value) becomes one, the determination of S14 becomes YES, and the wheel position corresponding to one wheel speed sensor 26 is identified in S15. Information IDa is associated. It is determined that the wheel information 50a including the identification information IDa is transmitted from the wheel side unit 12 of the wheel corresponding to the last remaining wheel speed sensor 26.

For example, when the count value Ci is supplied from the brake ECU 32, the detection value processing program represented by the flowchart of FIG. 9 can be executed by interruption.
In S21, count values (values supplied from the brake ECU 32) Can, Cbn, Ccn, Cdn which are detection values of the wheel speed sensors 26FL, FR, RL, RR are acquired (n = 0, 1, 2, 3 ...). In S22, it is determined whether the wheel position is being specified. If the wheel position is being specified, it is determined in S23 whether the set time has elapsed, that is, whether the count value is being acquired. If the count value is not being acquired, it is determined in S24 whether the count value acquisition start condition is satisfied. The start condition can be satisfied, for example, every set time. When the start condition is satisfied, in S25, the count values Can, Cbn, Ccn, Cdn of the wheel speed sensors 26FL, FR, RL, RR obtained in S21 are set to initial values Ca0, Cb0, Cc0, Cd0. Memorized. Further, the count value acquisition flag is set to ON.
Next, when this program is executed, since the count value acquisition flag is ON, the determinations in S22 and S23 are YES, and it is determined in S26 whether the set time has elapsed. It is determined whether or not the elapsed time since the start condition is satisfied has reached the set time. Before the set time elapses, S21, 22, 23, and 26 are repeatedly executed, and the count values Can, Cbn, Ccn, and Cdn of the wheel speed sensors 26FL, FR, RL, and RR are acquired during the set time. .

When the set time has elapsed, the count value acquisition flag is set to OFF, and the count value of each of the plurality of count values Cin output by each of the wheel speed sensors 26FL, FR, RL, RR has changed. Is determined. That is, it is determined that the count value does not change when the plurality of count values are the same, and it is determined that the count value has changed when some of the count values are different from each other.
In S27, whether or not the wheel speed sensor 26 that has output the count value that does not change is a part, that is, the wheel speed that has output the changed count value in the four wheel speed sensors 26FL, FR, RL, and RR. It is determined whether or not both the sensor 26 and the wheel speed sensor 26 that has output a count value that does not change exist. If both exist, the count processing values Ca (n) *, Cb (n) *, Cc (n) *, Cd (n) * of all wheel speed sensors 26 are the initial values Ca0, Cb0 in S28. , Cc0, Cd0, {Ci0 → Ci (n) *}.
Note that only the count processing value of the wheel speed sensor 26 whose count value has changed can be considered as the initial value of the count value. For example, the count values {(Ca0, Ca1, Ca2...), (Cb0, Cb1, Cb2...)} Do not change {(Ca0 = Ca1 = Ca2...), (Cb0 = Cb1 = Cb2. ..)}, When count values {(Cc0, Cc1, Cc2...)} (Cd0, Cd1, Cd2...)} Change {(Cc0 ≠ Cc1 ≠ Cc2...), (Cd0 ≠ Cd1) ≠ Cd2...}}, The count processing values (Cc (n) *, Cd (n) *) can be considered as the initial values (Cc0, Cd0).
On the other hand, if the count values for each of the plurality of wheels output by all the wheel speed sensors 26 have not changed, or if the count values output by all the wheel speed sensors 26 have changed, in S29. Normal processing is performed. The count processing value is set to the count values Can, Cbn, Ccn, and Cdn acquired in the immediately preceding S21 (Cin → Ci (n) *). For example, it corresponds to a case where the vehicle is in a running state.

Further, when this program is repeatedly executed, S28 may be executed after S29 is executed. In this case, the current count processing value is assumed to be the same as the previous count processing value. Therefore, the count processing value is assumed to be constant.
Ci (n) * ← Ci (n-1) *
Further, S29 may be executed after the count processing value is returned to the initial value in S28. In this case, in S29, the current count process value is obtained by counting with the previous count process value Ci (n-1) * as a reference. For example, the amount of change in the count value during the set time is acquired,
dCi = Cin-Ci0
By adding the change amount dCi of the count value to the previous count processing value, the current count processing value is acquired.
Ci (n) * ← Ci (n-1) * + dCi
The set time can be a time shorter than the time for which the wheel 10 makes one rotation, for example, a time during which the count value of the wheel speed sensor 26 is supplied from the brake ECU 32 a plurality of times. In the specification of the wheel position, the time is equal to or shorter than the interval at which the count processing value is read.

Thus, in the present embodiment, the count value of the wheel speed sensor 26 changes due to the relative movement between the vehicle body 14 and the wheel 10 even when the wheel 10 is not rotating while the vehicle is stopped. However, it is considered that there was no change. As a result, after starting the vehicle, the wheel position is continuously specified based on the count processing value of the wheel speed sensor 26 in order to specify the wheel position. Since the relationship between the detection value of the sensor 42 is substantially the same before and after the vehicle is stopped, the wheel position can be identified satisfactorily.
For example, in FIG. 11 (c), there are both the wheel speed sensor 26 in which the count value has changed and the wheel speed sensor 26 in which the count value has not changed, such as between time t1 and time t2 (during the set time). In some cases, the count value is considered unchanged. The count processing value Ci (2) * at time t2 is set as the count value at time t1, that is, the initial value Ci0 of the count value (S28).
Ci (2) * ← Ci0
Further, when the count values of all the wheel speed sensors 26 have not changed as during the time t2 to the time t3, the count processing value Ci (3) * at the time t3 is the count processing value at the time t2. Same as Ci (2) * (S29).
Ci (3) * ← Ci (2) *
Next, when there is both the wheel speed sensor 26 in which the count value has changed and the wheel speed sensor 26 in which the count value has not changed, such as between the time t3 and the time t4, the count processing value Ci * (4) at the time t4. Is set to the same value as the count processing value Ci (3) * at time t3 (S28).
Ci (4) * ← Ci (3) *
Then, when the count values of all the wheel speed sensors 26 have changed, such as between the time t6 and the time t7, the count-up value Ci (6) at the time t6 is counted up. The count value variation dCi between time t6 and time t7 is added to the count processing value Ci (6) * at time t6, thereby obtaining the count processing value Ci (7) * at time t7 (S29). .
Ci (7) * ← Ci (6) * + dCi
dCi ← Cin-Ci0

Thereafter, the count processing value is obtained by adding the amount of change dCi of the count value within the set time to the previous count processing value Ci (n-1) *, which is on the one-dot chain line in FIG. As indicated by the point, the value is shifted from the count value supplied from the brake ECU 32 by the count value where the change is ignored.
The wheel speed sensor 26 includes a type that counts up without distinguishing between forward rotation and reverse rotation of the rotor 56 and a type that counts up or down depending on the rotation direction of the rotor 56. In any case, since any change in the count value not caused by the rotation of the wheel 10 is ignored by the execution of this program, the detection value of the acceleration sensor 42 and the count processing value of the wheel speed sensor 26 The relationship can be kept almost constant.

In the present embodiment, a detection value processing unit is configured by a portion for storing and executing a detection value processing program represented by the flowchart of FIG. 9 of the TPMS ECU 30, and the flowchart of FIG. 8 of the detection value processing unit and the TPMS ECU 30. A wheel position specifying unit is configured by a part for storing the wheel position specifying program and a part for executing the program. The detected value processing unit is also a relationship change suppression unit. Of the detected value processing unit, a part for storing S24, 25, 27, and 28, a part for executing, etc. constitute a detected value holding part, a change ignoring part, and a change ignoring part during stop. Furthermore, the wheel position specifying unit is also a continuous wheel position specifying unit.

When the relationship between the detection value of the acceleration sensor 42 and the count value of the wheel speed sensor 26 may change, such as when the vehicle is stopped, the change in the count value of the wheel speed sensor 26 is prohibited. You can make it.
The count prohibition flag setting program represented by the flowchart of FIG. 12A is executed at predetermined time intervals.
In S31, the door opening / closing detection device 28 determines whether or not at least one of the plurality of opening / closing bodies provided in the vehicle is in an open state. When any one of the luggage door, the passenger side door, and the like is in an open state, it is considered that there is a high possibility that the passenger will get on and off, or the luggage will be lifted and lowered. In S32, it is determined whether or not the vehicle is stopped based on information from the navigation ECU 34 (hereinafter may be abbreviated as navigation information). If the opening / closing body is in the open state, or if the vehicle is considered to be in a stopped state based on the navigation information, the count prohibition flag is turned ON in S33. On the other hand, when all the opening / closing bodies are in the closed state and the vehicle is in the traveling state, the count prohibition flag is turned OFF in S34.

The detection value processing program represented by the flowchart of FIG. 12B is executed by interruption.
In S41, the count values as the detection values of the four-wheel wheel speed sensors 26FL, FR, RL, RR are acquired. In S42, it is determined whether the wheel position is being specified. In S43, it is determined whether the count prohibition flag is ON.
If the count prohibition flag is ON, the determination in S43 is YES, and in S44, it is determined whether the count prohibition flag was previously turned off, that is, whether the count prohibition flag was first turned on. The When the count prohibition flag is first turned ON, the count values of the wheel speed sensors 26FL, FR, RL, RR acquired in S41 are stored as initial values in S45 (Ca0, Cb0, Cc0, Cd0). Thereafter, in S46, while the count prohibition flag is ON, the count processing value Ci (n) * is set to the initial value Ci0. On the other hand, if the count prohibition flag is not ON, normal processing is performed in S47. In principle, the count value acquired in S41 is assumed to be the output value of the sensor (Ci (n) * ← Cin).
Further, when S46 is executed after S47 is executed, the current count processing value is assumed to be the same as the previous count processing value.
Ci (n) * ← Ci (n-1) *
Further, when S47 is executed after the execution of S44 to S46, the count processing value of the previous time, that is, the count processing value Ci (n-1) * at that time is used as a reference.

Thus, in this embodiment, as shown in FIG. 13 (c), when the vehicle is in a stopped state, or when the opening / closing body is in an open state, the prohibition flag is turned ON and all wheel speeds are set. The count processing value of the sensor 26 is held at a constant value. Therefore, even if the count value is changed due to the relative movement between the wheel 10 and the vehicle body 14 while the vehicle is stopped, the count processing value remains the initial value of the count value. The count processing value Ci (n-1) * is counted as a reference. As a result, a change in the relationship between the detection value of the acceleration sensor 42 and the count processing value of the wheel speed sensor 26 can be suppressed, and the wheel position can be identified favorably.
In the present embodiment, the detected value holding unit and the detected value holding unit during stop, etc. are configured by the part for storing S43 to S46 of the detected value processing program represented by the flowchart of FIG. Is done.

This embodiment is applied to a type in which the wheel speed sensor 26 is counted up regardless of whether the rotor 56 is rotating in the backward direction or in the forward direction. .
When the shift position is at R and the wheel 10 is rotating in the reverse direction, the countdown is performed. When the shift position is not R, processing according to the state of the vehicle is performed as in the first and second embodiments.
In S51 of the flowchart of FIG. 14 representing the detection value processing program, the count values Cin of the wheel speed sensors 26FL, FR, RL, RR of each wheel are acquired. If the wheel position is being specified, the determination in S52 is YES, and it is determined in S53 whether or not the shift position is R (reverse) based on the detection value of the shift position sensor 27. If the shift position is D, N, etc., processing corresponding thereto, for example, processing similar to that in the first and second embodiments is performed in S54.
On the other hand, when the vehicle is moving backward, a reverse process is performed. In S55, the increment dCi of the count value Cin is acquired, and in S56, the current count processing value is obtained by subtracting from the previous count processing value.
Ci (n) * = Ci (n-1) *-dCi
The increment of the count value Cin is acquired as a value (for example, Ci2-Ci1) obtained by subtracting the previous count value from the current count value.
In addition, when the forward travel after the reverse is performed, the count is counted up based on the previous count processing value Ci (n-1) *.

As described above, when the wheel 10 is rotated in the reverse direction, the countdown value is counted down from the previous count processing value, so that the relationship between the count processing value of the wheel speed sensor 26 and the detection value of the acceleration sensor 42 is well maintained. Thus, even when the vehicle travels forward after the vehicle has moved backward, the wheel position can be identified satisfactorily.
In the present embodiment, a countdown unit is constituted by a part for storing S53 to S57 of the detection value processing program represented by the flowchart of FIG.

In the present embodiment, when the count value of the wheel speed sensor 26 changes while the vehicle is stopped, the setting range used for specifying the wheel position is changed.
In S61 of the flowchart of FIG. 15 representing the detection value processing program, the count values Cin of the wheel speed sensors 26FL, FR, RL, RR of each wheel are acquired, and it is determined in S62 whether the wheel position is being specified. In S63, it is determined whether or not the vehicle is stopped based on the navigation information. If both of the determinations in S62 and 63 are YES, it is determined in S64 whether or not it is first determined that the vehicle is in a stopped state. If it is the first, the acquisition is performed in S61 in S65. The count values Cin of the wheel speed sensors 26FL, FR, RL, RR of each wheel are set as the initial value Ci0 and stored. Next, when this program is executed, since this is not the first time, in S66, the initial value Ci0 is subtracted from the count value Cin of the wheel speed sensors 26FL, FR, RL, RR of each wheel acquired in S61. The value ΔCi is acquired and stored.
ΔCi ← Cin−Ci0
The value stored in S66 is updated as appropriate. The amount of change in the count value while the vehicle is stopped is acquired and updated.
When the vehicle has started, the determination at S63 is NO, and at S67, it is determined whether or not the determination at S63 is NO, that is, whether the vehicle has started after stopping. When the vehicle starts after the stop, that is, when S67 is executed for the first time, in S68, the set range expansion ΔSRci is obtained based on the change amount ΔCi acquired in S66, and the changed setting range (SRci + ΔSRci) is obtained. Desired.
ΔSRci ← ΔCi
SRci * ← SRci + ΔSRci
The set range expansion ΔSRci may be the same value as the count value change amount ΔCi when the vehicle is stopped or may be different. In any case, when the change amount ΔCi of the count value when the vehicle is stopped is large, the enlargement ΔSRci of the setting range is made larger than when it is small.

The setting range may be changed individually or in common for each of the wheel speed sensors 26FL, FR, RL, RR. For example, for the four wheel speed sensors 26, the set range expansion ΔSRc is determined based on the maximum value, average value, etc. of the count value change amount, and the set ranges for the four wheel speed sensors 26 are similarly expanded. Thus, the change setting range SRc * can be determined.
Even if the setting range is changed when at least one count value of the four wheel speed sensors 26FL, FR, RL, RR is changed in a stop state of the vehicle, the four wheel speeds are changed. It may be performed when the count values of all the sensors 26 have changed. Even when the vehicle is detected to be in a stopped state based on the navigation information, the wheel 10 may actually rotate and the vehicle may move slightly. Therefore, when the count values of all the four wheel speed sensors 26 are changed, it is caused by the relative movement between the vehicle body 14 and the wheel 10 (not caused by the rotation of the wheel 10) or caused by the rotation of the wheel 10. It is not clear what to do. Therefore, when it cannot be determined that it is caused by the relative movement between the wheel 10 and the vehicle body 14, that is, when all the count values of the four wheel speed sensors 26 change, the change in the count value is not ignored, The setting range was expanded.

Then, the wheel position is specified based on the changed setting range, and the wheel position specifying program represented by the flowchart of FIG. 16 is executed at predetermined time intervals.
When the vehicle is traveling and wheel information is received by the receiver 22, the count value Cin of the wheel speed sensor 26 is acquired in S12x. Then, in S13b, the changed setting range SRi * is read, and in S13x, it is determined whether or not the count value Cin exists within the changed setting range SR *. Hereinafter, in the same manner as in the above embodiment. The wheel position is specified. In this embodiment, it is not determined whether or not the count processing value is within the change setting range, but it is determined whether or not the count value is within the change setting range.
For example, as shown in FIG. 17, when the count value of the four wheel speed sensors 26 is changed in the stop state of the vehicle, the enlargement ΔSRc of the setting range is obtained based on the change amount and changed. A setting range is required. As a result, it is possible to satisfactorily identify the wheel position even if the relationship changes.

  In the present embodiment, the change amount acquisition unit is configured by a part that stores S64 to 66, 68 of the detection value processing program represented by the flowchart of FIG. The setting range changing unit is configured by the part to be executed, and the continuous wheel position specifying unit is configured by the part for storing the wheel position specifying program represented by the flowchart of S15, the part to be executed, and the like.

In the present embodiment, it is determined whether or not both the wheel speed sensor 26 whose count value changes and the wheel speed sensor 26 whose count value does not change exist while the vehicle is stopped. When the change in value is ignored and the count values of all wheel speed sensors 26 change, the setting range is changed.
The detection value processing program represented by the flowchart of FIG. 18 is executed by an interrupt or the like.
In S81 and 82, the count value Cin is acquired and it is determined whether or not the position is being specified. If the position is being specified, whether or not the vehicle is in a stopped state based on the navigation information or the like in S83. If it is determined whether or not it is in a stopped state, it is determined in S84 whether it is the first time that it has been determined that it is in a stopped state. The value is stored as the initial value Ci0.
Thereafter, S81 to 84, 86 are repeatedly executed during the set time, the count value Cin is acquired, and after the set time has elapsed, the wheel speed sensor 26 that outputs the changed count value and the count value that does not change are output. It is determined whether or not both of the wheel speed sensors 26 are present (S87). If both exist, the change ignore flag is set to ON in S88, and the count processing value is set to the initial value in S89. Note that the current value of the count processing value may be the previous value.
Ci (n) * ← Ci0
Ci (n) * ← Ci (n-1) *
While the vehicle is in a stopped state, S81 to S84 and 86 to 89 are executed, whereby the count processing value is held at a constant value, and the change in the count value is ignored.
When the vehicle starts, the determination in S83 is NO, and in S90, it is determined whether or not the change ignore flag is ON. If the change ignorance flag is ON, in S91, the current count processing value Ci (n) * is obtained by counting from the previous count processing value Ci (n-1) *.

On the other hand, when all the count values of the wheel speed sensors 26FL, FR, RL, and RR have changed, the determination in S87 is NO and the change ignore flag remains OFF. While the vehicle is in a stopped state, S81 to 84, 86, and 87 are repeatedly executed. Thereafter, when the vehicle starts, whether or not S92 is first executed in S92, that is, the vehicle starts after stopping. Whether or not S92 has been executed is determined, and if it is the first time, in S93 and 94, the amount of change ΔCi of the count value when the vehicle is in a stopped state is acquired, and the change in the setting range (enlargement) ) Is acquired, and the change setting range is acquired.

When the change in the count value is ignored, it is determined whether or not the count processing value is within the set range by executing the wheel position specifying program shown in the flowchart of FIG. When the specification is performed and the setting range is changed, it is determined whether or not the count value is within the change setting range by executing the wheel position specifying program shown in the flowchart of FIG. Identification is done.
If some of the count values of the four wheel speed sensors 26FL, FR, RL, and RR do not change and the rest changes, the vehicle is stopped and the relative movement between the vehicle body 14 and the wheels 10 occurs. Therefore, it can be determined that the count values of some of the wheel speed sensors 26 have changed (without causing the rotation of the wheel 10).
However, when the count values of all the wheel speed sensors 26 change, it is unknown whether the change is caused by the rotation of the wheel 10 or the change not caused by the rotation of the wheel 10. This is because even if it is determined that the vehicle is stopped based on the navigation information, the vehicle may be moving slightly. Therefore, when the count values of all the wheel speed sensors 26 are changed, the change of the count value is not ignored, but the setting range is changed so that the wheel position is specified. As described above, since it is not clear whether the change in the count value is caused by the rotation of the wheel 10 or not due to the rotation of the wheel 10, the change in the count value is not ignored. Even if it is a change which changes, a wheel position can be specified satisfactorily.

  In addition, the present invention can be executed by appropriately combining the examples of the first to fourth embodiments. In addition to the above-described aspects, the present invention can be implemented in various aspects based on the knowledge of those skilled in the art. Can be implemented.

  DESCRIPTION OF SYMBOLS 10: Wheel 12: Wheel side unit 14: Car body 16: Car body side apparatus 22: Receiver 24: Display 26: Wheel speed sensor 27: Shift position sensor 28: Door opening / closing detection apparatus 30: TPMS ECU 32: Brake ECU 34: Navigation ECU 40: Air pressure sensor 42: Acceleration sensor 44: Transmitter 50: Wheel information 53: Identification information 54: Air pressure information 56: Rotor 58: Teeth

Claims (9)

Provided on each of a plurality of wheels of the vehicle, (a) a wheel-side rotation sensor that detects a rotation position of the wheel; and (b) the wheel-side rotation sensor that is determined based on a detection value of the wheel-side rotation sensor. A wheel-side device including a transmission unit that transmits at least wheel information including identification information set for the wheel at a timing when the position with respect to the wheel reaches a predetermined position;
(I) a receiver that receives wheel information transmitted from each of the plurality of wheel-side devices; and (ii) a rotational position of the wheel corresponding to each of the plurality of wheels. And (iii) target wheel information which is wheel information transmitted from the target wheel side device which is one of the plurality of wheel side devices by the receiver. Is received by each of the vehicle body side rotation sensors, and based on each of the detected values, the target wheel that is the wheel that transmitted the target wheel information is detected. A wheel position specifying device including a vehicle body side device including a wheel position specifying unit that specifies one corresponding vehicle body side rotation sensor and associates the identification information included in the target wheel information with the position of the target wheel. There,
When the vehicle is in a set state during execution of the wheel position specifying unit, the wheel position specifying unit detects at least one detection value of the plurality of vehicle body side rotation sensors according to the state of the vehicle. A wheel position specifying device including a detected value processing unit for processing The detection value processing unit processes at least one detection value of the plurality of vehicle body side rotation sensors, whereby each of the detection values of the at least one vehicle body side rotation sensor and the wheel side rotation corresponding to them. The wheel position specifying device according to claim 1, further comprising a relationship change suppression unit that suppresses a change in relationship with each of the detection values of the sensor. The detection value processing unit is (i) a change ignoring unit that ignores a change in at least one of the plurality of wheel side rotation sensors, and (ii) the at least one detection value is constant. 3. The wheel position specifying device according to claim 1, comprising at least one of a detection value holding unit and (iii) a countdown unit that decreases a count value that is a detection value of the plurality of wheel side rotation sensors. In the case where the detection value processing unit is at least one of a case where the vehicle is in a stopped state and a state where at least one of a plurality of opening / closing bodies provided in the vehicle is open, the plurality The wheel position specifying device according to any one of claims 1 to 3, further comprising a detected value holding unit such as during stoppage, wherein each detected value of the vehicle body side rotation sensor is constant. The detection value processing unit is in a stopped state when a detection value of a part of the plurality of vehicle body side rotation sensors changes during a predetermined set time and the remaining detection values do not change. 5. The wheel position specifying device according to claim 1, further comprising: a change ignoring unit during stop that ignores a change in the detection value of each of the some vehicle body side rotation sensors. Change in which the detection value processing unit acquires a change amount of each of the at least one detection value when at least one detection value of the plurality of vehicle body side rotation sensors changes in the stop state of the vehicle. A change amount-dependent wheel position specifying unit that specifies the wheel position in consideration of a change amount of the at least one detection value acquired by the change amount acquisition unit. The wheel position specifying device according to any one of claims 1 to 5. The wheel position specifying unit includes a variation acquisition unit that determines whether or not each detection value of the plurality of vehicle body side rotation sensors is within a set range, and the variation-dependent wheel position specifying unit includes (A) a setting range individual changing unit that individually changes the setting range based on a change amount of a detection value of the vehicle body side rotation sensor corresponding to the setting range; and (b) the at least one detection of the setting range. The wheel position specifying device according to claim 6, comprising at least one of a setting range common changing unit that changes in the same manner based on at least one of the change amounts of the values. When the detection value processing unit detects that the vehicle is in a stopped state, (a) the detection values of some of the vehicle body side rotation sensors of the plurality of vehicle body side rotation sensors change, and the remaining A change ignoring unit for ignoring a change in detection values of some of the vehicle body side rotation sensors when the detection value of the vehicle body side rotation sensor does not change, and (b) all of the detection values of the plurality of vehicle body side rotation sensors are The wheel position specifying device according to any one of claims 1 to 7, further comprising: a change amount acquisition unit that acquires the change amounts of the plurality of detection values when changed. Provided on each of a plurality of wheels of the vehicle, (a) a wheel-side rotation sensor that detects a rotation position of the wheel; and (b) the wheel-side rotation sensor that is determined based on a detection value of the wheel-side rotation sensor. A wheel-side device including a transmission unit that transmits at least wheel information including identification information set for the wheel at a timing when the position with respect to the wheel reaches a predetermined position;
(I) a receiver that receives wheel information transmitted from each of the plurality of wheel-side devices; and (ii) a rotational position of the wheel corresponding to each of the plurality of wheels. And (iii) target wheel information which is wheel information transmitted from the target wheel side device which is one of the plurality of wheel side devices by the receiver. Is received by each of the vehicle body side rotation sensors, and based on each of the detected values, the target wheel that is the wheel that transmitted the target wheel information is detected. A wheel position specifying device including a vehicle body side device including a wheel position specifying unit that specifies one corresponding vehicle body side rotation sensor and associates the identification information included in the target wheel information with the position of the target wheel. There,
When the vehicle is in a set state during execution of the wheel position specifying unit, the wheel position specifying unit continues to specify the wheel position in consideration of the state. A wheel position specifying device comprising:

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