Device for displaying fuel efficiency degradation amount based on tire air pressure

• US 20060202811A1
• Filed: 01/11/2006
• Published: 09/14/2006
• Est. Priority Date: 02/25/2005
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Taguchi, Akihiro
• Granted Patent: US 7,501,940 B2
• Time in Patent Office: Days
• US Class Current: 340/450.200
• CPC Class Codes: B60C 23/04 mounted on the wheel or tyre
• CPC Class Codes: B60C 23/0401 characterised by the type of alarm
• CPC Class Codes: G07C 5/0816 Indicating performance data, e.g. occurrence of a malfunction

Abstract

A fuel efficiency degradation amount displaying device detects a tire air pressure and calculates an amount of degradation of fuel efficiency of the vehicle compared to fuel efficiency in a case that the tire air pressure is appropriate. Then the fuel efficiency degradation amount displaying device indicates not only a warning of the decrease of the tire air pressure but also the amount of the fuel efficiency degradation. Therefore the driver can recognize the amount of the degradation clearly and intuitively. As a result, it is possible to prevent drivability of the vehicle from getting worse, because the driver can adjust, knowing a relation between the tire air pressure and the fuel efficiency, the tire air pressure to the appropriate tire air pressure.

Claims

1. A fuel efficiency degradation amount displaying device, comprising:

a tire air pressure detecting unit for outputting a detection signal depending on a tire air pressure of a wheel attached to a vehicle;

a fuel efficiency degradation amount specifying unit for specifying based on the outputted detection signal an amount of degradation of fuel efficiency of the vehicle compared to fuel efficiency of the vehicle in a case that the tire air pressure is appropriate; and

a displaying unit for displaying the specified amount of the degradation.

2. The fuel efficiency degradation amount displaying device according to claim 1, wherein the fuel efficiency degradation amount specifying unit specifies the amount of degradation of the fuel efficiency based on a stored relation describing a correspondence between the tire air pressure and the amount of degradation of the fuel efficiency.

3. The fuel efficiency degradation amount displaying device according to claim 1, further comprising:

a low tire air pressure determination unit for making, based on the outputted detection signal, a determination whether the tire air pressure is below a predetermined threshold,

wherein the displaying unit displays, based on that the determination is affirmative, information indicating decrease of the tire air pressure.

4. The fuel efficiency degradation amount displaying device according to claim 3, wherein the fuel efficiency degradation amount determining unit specifies, based on that the determination is negative, the amount of degradation of fuel efficiency.

5. The fuel efficiency degradation amount displaying device according to claim 1, further comprising:

a pressure shortage detecting unit for detecting, based on the outputted detection signal, a degree of shortage of the tire air pressure compared to an appropriate tire air pressure,

wherein the displaying unit displays the detected degree of the shortage of the tire air pressure.