Method and apparatus for thermal testing of brake performance

• US 6,442,457 B1
• Filed: 01/08/2000
• Issued: 08/27/2002
• Est. Priority Date: 07/19/1997
• Status: Expired due to Fees

• Current Assignee: Snap-on Equipment Ltd. (Snap-On Incorporated)
• Original Assignee: Snap-on Equipment Ltd. (Snap-On Incorporated)
• Inventors: Davis, Stephen J., Jones, Barbara L.
• Primary Examiner(s): Camby, Richard M.
• Application Number:
  US09/463,031
• Time in Patent Office: 962 Days
• Field of Search: 701/29, 701/31, 701/33, 701/35, 731/21, 731/29
• US Class Current: 701/29
• CPC Class Codes: B60T 17/221 Procedure or apparatus for checking or keeping in a correct functioning condition of brake systems hydraulic pressure systems in general F15B19/00, F15B21/04; testing structures or apparatus G01M
• CPC Class Codes: F16D 2066/001 Temperature
• CPC Class Codes: G01L 5/28 for testing brakes
• CPC Class Codes: G01M 17/02 Tyres

Abstract

Vehicle thermal testing method and apparatus is based upon the use of a mobile handset. The handset uses spot infra red thermal sensing to identify thermal imbalance between wheels on opposite sides or the same side of a vehicle. Testing identifies thermal levels resulting from braking by mere application of the handset to wheel nuts after a short brake application and without use of roller test beds or other such equipment. Tires can be similarly tested. The handset can generate test instructions. Repetition of an initial test enables the offset for cooling during the test to be verified. A similar technique applies to tires. The handset may communicate with a base station providing for keyboard input of vehicle data and results printout.

Claims

1. A method for analysis of brake performance in automotive vehicles comprising:

a) providing sensing means including infra-red spot sensor means and causing same to sense the temperature of a location on a brake structure; and

b) comparing data from at least two such brake structure sensing steps to determine the degree of brake imbalance present;

 

charactised by

c) inputting data to said sensing means or to a test control system associated therewith relating to vehicle type or wheel or brake structure characteristics;

d) providing said sensing means with a mobile testing handset and causing said handset to generate testing instructions in accordance with the method to be carried out for a given structure under test;

e) carrying out testing steps on at least two brake structures of at least one axle of said vehicle by means of said handset in accordance with said instructions displayed by said handset and thereby generating test data relating to said brake performance; and

f) said testing steps being carried out in a sequence defined and in accordance with said instructions and including a repetition of at least one step of said sequence whereby allowance made for the effect of the time taken to carry out said sequence of steps can be checked and adjusted if necessary.

4. A method according to any one of claim 1 or 3 characterised by said handset having a communications link to a data handling system and said method comprising sensing test data at said handset and transmitting same to said data handling system through said communications link.

5. A method according to claim 4 characterised by said communications link being established by locating said handset at a defined position with respect to said data handling system after sensing said test data.

6. A method according to any one of claim 1 or 5 characterised by carrying out said test steps with said handset at a distance from said vehicle wheels or other vehicle component defined by a location-and-distance-defining locator device.

7. A method according to claim 6 characterised by locating said locater device on a vehicle wheel nut or other vehicle projection or structure.

8. A method according to any one of claim 1 or 7 characterised by causing said handset to display said instructions at least in part by means of energy pulses.

9. A method according to claim 8 characterised by said energy pulses being of varying duration and/or colour/frequency.

10. A method according to claim 9 characterised by said light pulses being displayed in a device representing one or more aspects of the construction of the vehicle wheels or braking system so as to indicate the location at which a test is to be made.

2. Apparatus for analysis of brake performance in automotive vehicles, comprising:

a) sensing means including infra-red spot sensor means adapted to sense the temperature of a location on a brake structure connected thereto;

b) comparator means adapted to compare data from at least two such brake structure sensing steps to determine the degree of braking imbalance;

 

characterised by

c) data input means adapted to permit the inputting of data to said sensing means or to a test control system associated therewith relating to vehicle type or wheel or brake structure characteristics;

d) said sensing means comprising a mobile testing handset adapted to generate testing instructions in accordance with the method to be carried out for a given vehicle type or wheel or brake structure characteristics under test;

e) said handset being adapted to generate said testing instructions for said sensing steps and defining a sequence of steps and including a repetition of at least one step of said sequence whereby allowance made for the effect of time taken to carry out said sequence of steps can be checked and adjusted if necessary.

3. A method of analysis of thermal distribution in a vehicle system comprising heat generating means, the method comprising:

a) causing a vehicle to execute an amount of thermal distribution in relation to at least a pair of assemblies or components or systems to be tested to provide an opportunity to generate at least a minimum quantum of heat for test purposes;

b) providing thermal sensor means and causing same to sense the temperature of a first such assembly or component or system;

c) taking said sensor means to a second such assembly or component or system which normally constitutes with said first such assembly or component or system a thermally related pair, and causing said thermal sensor means to sense the temperature of said second assembly or component or system;

d) providing thermal comparator means adapted to compare the temperatures of said assemblies or components or systems and adapted to indicate the state of thermal balance or imbalance or thermal relationship thereof and causing same to effect such comparison and indication in relation to said first and second assemblies or components or systems;

 

characterised by

e) providing said sensor means as part of a mobile handset adapted to be hand-held by a user at a location close to or adjacent each such assembly or component or system to be tested;

f) providing said handset with its own locator means operative in relation to said thermal sensor means to enable the user rapidly to position same in relation to said assemblies or components to be tested so as to provide a valid comparison basis between said temperature sensing steps.

11. Apparatus for effecting analysis of thermal distribution in a vehicle system comprising heat generating means, the apparatus comprising:

a) thermal sensor means adapted to sense the temperature of a first assembly or component or system to be tested after a vehicle incorporating same has executed an amount of thermal distribution so as to provide an opportunity for generation of at least a minimum quantum of heat for test purposes;

b) said sensor means being likewise adapted to sense in relation to a second such assembly or component or system which normally constitutes with said first such assembly or component or system a thermally balanced or related pair, whereby said thermal sensor means can sense the temperature of said second such assembly or component;

c) thermal comparator means adapted to compare the temperatures of said assemblies or components and adapted also to indicate the state of thermal balance or imbalance or relationship;

 

characterised by

d) said sensor means being provided as part of a mobile handset adapted to be handheld by a user at a location close to or adjacent each such assembly or component or system to be tested;

e) said handset comprising its own locator means operative in relation to said thermal sensor means to enable the user rapidly to position same in relation to said assemblies or components or systems to be tested so as to provide a valid comparison basis between said temperature sensing steps.

12. Apparatus according to any one of claim 2 or 11 characterised by said handset having a communications link to a data handling system or base station, and said handset being adapted to sense test data and to transmit same to said base station through said communication link.

13. Apparatus according to claim 12 characterised by said communications link being adapted to be established by locating said handset at a defined position with respect to said data handling system or base station after sensing said data.

14. Apparatus according to any one of claim 2 or 13 characterised by a locater device adapted to define a test location and distance for said handset from said vehicle wheels.

15. Apparatus according to claim 14 characterised by said locater device being adapted to be located on a wheel nut or other vehicle component or projection on said vehicle wheel.

16. Apparatus according to any one of claim 2 or 15 characterised by said handset being adapted to display said instructions at least in part by means of energy pulses.

17. Apparatus according to claim 16 characterised by said light pulses being of varying duration and/or colour.

18. Apparatus according to claim 17 characterised by said light pulses being displayed in a device representing one or more aspects of the construction of a vehicle'"'"'s wheels or braking system so as to indicate the location at which a test is to be made.