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

• US 7,501,940 B2
• Filed: 01/11/2006
• Issued: 03/10/2009
• Est. Priority Date: 02/25/2005
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Taguchi, Akihiro
• Primary Examiner(s): Ortiz; Angela
• Assistant Examiner(s): Mortell; John F
• Application Number:
  US11/329,108
• Publication Number:
  US 20060202811A1
• Time in Patent Office: 1,154 Days
• Field of Search: 340/442, 340/443, 340/444, 340/445, 340/447, 340/449, 340/436, 340/870.03, 340/870.05, 340/870.06, 340/517, 340/518, 340/520, 340/521, 340/522, 340/525, 340/526, 340/539.1, 340/539.16, 340/539.22, 340/539.24, 340/539.26, 340/539.27, 340/539.28, 340/665, 340/666, 340/438, 340/439, 340/450, 340/450.2, 701/123, 701/124, 701/129, 701/29, 701/104, 701/24, 701/30, 701/33
• US Class Current: 340/442
• 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;

a displaying unit for displaying the specified amount of the degradation; and

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 the determination being affirmative, information indicating decrease of the tire air pressure;

the fuel efficiency degradation amount determining unit specifies, based on the determination being negative, the amount of degradation of fuel efficiency; and

the displaying unit changes the display thereof from the amount of degradation of fuel efficiency to the information indicating decrease of the tire pressure when the determination is changed from negative to affirmative.

2. 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.