Wheel position detecting device that verifies accuracy of detection using trigger signal reception strength and tire air pressure detecting device including the same

• US 20080068148A1
• Filed: 09/18/2007
• Published: 03/20/2008
• Est. Priority Date: 09/19/2006
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Mori, Masashi
• Granted Patent: US 7,750,798 B2
• Time in Patent Office: Days
• US Class Current: 340/447
• CPC Class Codes: B60C 23/0416 allocating a corresponding wheel position on vehicle, e.g. front/left or rear/right

Abstract

A wheel position detecting device and a tire air pressure detecting device including the wheel position detecting device are provided. The wheel position detecting device judges whether reception strength data is correct or incorrect based on whether reception strength indicated by the reception strength data (the reception strength data expresses the reception strength of a signal transmitted from a receiver, provided in a vehicle body, to a transmitter at the transmitter) transmitted from each transmitter is within a range set in advance. Each transmitter is provided on each wheel. The wheel position detecting device judges whether to decide the wheel position using the reception data.

Claims

1. A detecting apparatus detecting a position of a plurality of wheels provided on a body of a vehicle, the apparatus comprising a plurality of transmitters, each of the plurality of transmitters provided on each of the plurality of wheels, and a receiver provided on the body,

each of the plurality of transmitters comprising:

a first receiving unit receiving a trigger signal sent from the receiver;

a first controlling unit detecting a reception strength of the trigger signal and producing a reception strength-data representing the reception strength; and

a transmitting unit transmitting the reception strength data to the receiver;

and

the receiver comprising;

a triggering unit sending the trigger signal to at least two of the plurality of transmitters;

a second receiving unit receiving each of the reception strength data from each the sending unit; and

a second controlling unit deciding whether or not adopting each of the reception strength data for detecting the position based on whether or not each of the reception strength is within a predetermined range.

2. The detecting apparatus of claim 1, wherein the second controlling unit instructs the triggering unit to resend the trigger signal to the plurality of transmitters either when the second receiving unit fails to receive at least one of the reception strength data or when at least one of the reception strength is out of the predetermined range.

3. The detecting apparatus of claim 2, wherein the second controlling unit detects whether or not the vehicle is running and instructs the triggering unit to send the trigger signal to the plurality of transmitters when the vehicle is running.

4. The detecting apparatus of claim 2, wherein

the triggering unit comprises a first and second triggering units, the first triggering unit sending the trigger signal to a first group of the plurality of transmitters, the second triggering unit sending the trigger signal to a second group of the plurality of transmitters, and

the second control unit instructs the first triggering unit to resend the trigger signal to at least one of the first group of the plurality of transmitters when the second receiving unit fails to receive the reception strength data of the at lease one, and

the second control unit instructs the second triggering unit to resend the trigger signal to at least second one of the second group of the plurality of transmitters when the second receiving unit fails to receive the reception strength data of the at lease second one.

5. The detecting apparatus of claim 4, wherein

the first group is consisted of the transmitters provide on the wheels located in a front side of the body, and

the second group is consisted of the transmitters provide on the wheels located in a rear side of the body.

6. The detecting apparatus of claim 1, wherein

the second controlling unit further comprises a judging unit judging whether or not the number of reception strength data, of which the reception strength is within the predetermined range, is a predetermined number, and

the second controlling unit instructs the triggering unit to resend the trigger signal when the number of reception strength data, of which reception strength is within the predetermined range, is different from the predetermined number.

7. A detecting apparatus for detecting an air-pressure of a tire fitted around each of the plurality of wheels comprising the detecting apparatus of claim 1, wherein

each of the plurality of transmitters further comprises a sensor sensing the air-pressure and outputting a signal representing the sensed air-pressure to the first control unit,

the first control unit produces a sensed air-pressure data representing the sensed air-pressure and outputs the sensed air-pressure data to the first sending unit,

the first transmitting unit transmits the sensed air-pressure data;

and

the receiver detects each of the air-pressure using the second control unit based on the sensed air-pressure data.