Method for determining the power of a test specimen and power test bench for the test specimen

• US 6,986,292 B2
• Filed: 06/21/2004
• Issued: 01/17/2006
• Est. Priority Date: 12/20/2001
• Status: Expired due to Term

• Current Assignee: ABB Patent GmbH (ABB Limited)
• Original Assignee: ABB Patent GmbH (ABB Limited)
• Inventors: Kemnade, H.-Jürgen
• Primary Examiner(s): NOORI, MAX H
• Application Number:
  US10/873,402
• Publication Number:
  US 20050016295A1
• Time in Patent Office: 575 Days
• Field of Search: 731/16, 731/172, 731/173, 738/62, 738/620.8, 738/621.91
• US Class Current: 73/862.191
• CPC Class Codes: F02D 2200/1015 Engines misfires
• CPC Class Codes: G01M 15/044 by monitoring power, e.g. by operating the engine with one of the ignitions interrupted; by using acceleration tests
• CPC Class Codes: G01M 15/046 by monitoring revolutions for detecting misfire G01M15/11

Abstract

A method for determining the power of a test specimen, in particular of an internal combustion engine, includes registering a time profile of the rotational speed and of the torque characteristic of an output shaft of the test specimen with a measuring device. To determine the power at a specific time, the time profile of the rotational speed and of the torque characteristic is exclusively measured. The test specimen is tested within a time period during which there is no necessity for forced cooling. A test bench for carrying out the method is also provided.

Claims

1. A method for determining a power of a test specimen having an output shaft, which comprises:

registering a time profile of a rotational speed and of a torque characteristic of the output shaft of the test specimen with a measuring device;

exclusively measuring the time profile of the rotational speed and of the torque with the measuring device to determine the power of the test specimen at a specific time; and

testing the test specimen within a time period during which there is no necessity for forced cooling of the test specimen.

2. The method according to claim 1, which further comprises calculating the power of the test specimen at the specific time according to the formula:

P(t)=M(t)[Nm]*n(t)/9550,

where;

P(t)=power P at the specific time (t);

M(t)=torque of the output shaft at the specific time (t); and

n(t)=rotational speed at the specific time (t).

3. The method according to claim 1, which further comprises driving the test specimen with a starter until a predefined rotational speed specific to the test specimen is reached.

4. The method according to claim 1, which further comprises starting independent operation of the test specimen when the test specimen reaches a predefined rotational speed.

5. The method according to claim 3, which further comprises switching off the starter after one of:

the predefined rotational speed is reached; and

if the test specimen is running under its own power.

6. The method according to claim 5, which further comprises starting independent operation of the test specimen when the test specimen reaches the predefined rotational speed.

7. The method according to claim 6, which further comprises decoupling the starter from the test specimen.

8. The method according to claim 7, which further comprises accelerating the test specimen to a maximum rated rotational speed when the test specimen is running under its own power.

9. The method according to claim 8, which further comprises carrying out the acceleration with a predefinition of a full load value for the rotational speed.

10. The method according to claim 1, which further comprises:

determining a number of power values of the test specimen at defined rotational speed values;

connecting the power points between the measured rotational speeds with an interpolation method; and

storing the power curve so determined as a function of at least one of the rotational speed and the measured values.

11. The method according to claim 10, which further comprises carrying out the power point connecting step by connecting the power points between the measured rotational speeds with a linear interpolation method.

12. The method according to claim 1, which further comprises:

providing a test bench set up for power testing; and

testing the test specimen in the test bench.

13. The method according to claim 12, which further comprises placing the test specimen in a test position in the test bench where the power testing is to be carried out.

14. The method according to claim 13, which further comprises permanently connecting the test specimen to the test bench in the test position.

15. The method according to claim 13, which further comprises removably fixedly connecting the test specimen to the test bench in the test position.

16. The method according to claim 13, which further comprises:

providing a starter for starting the test specimen; and

coupling the starter to the output shaft of the test specimen with a coupling device.

17. The method according to claim 13, which further comprises:

providing a starter for starting the test specimen; and

coupling the starter to the output shaft of the test specimen by interposing a measuring and coupling device.

18. The method according to claim 12, which further comprises connecting a fuel supply device to the test specimen.

19. The method according to claim 12, which further comprises:

providing the test specimen with a control system; and

connecting control and data lines for actuating the test specimen to the control system.

20. The method according to claim 12, which further comprises:

providing the test specimen with an exhaust gas system;

connecting an exhaust gas discharge line device to the exhaust gas system of the test specimen; and

carrying away any exhaust gases produced during a test from a region of the test bench with the exhaust gas discharge line device.

21. The method according to claim 10, which further comprises picking up measured values with an evaluation device.

22. The method according to claim 21, which further comprises graphically representing the measured values and making the measured values available for further data processing.

23. The method according to claim 1, which further comprises at least one of controlling and regulating a test sequence of the test specimen with a control device.

24. The method according to claim 1, wherein the test specimen is an internal combustion engine.