Reciprocating engine cylinder contribution tester and method

• US 7,010,460 B2
• Filed: 10/30/2003
• Issued: 03/07/2006
• Est. Priority Date: 10/30/2003
• Status: Expired due to Fees

• Current Assignee: Snap-On Technologies Incorporated (Snap-On Incorporated)
• Original Assignee: Snap-On Incorporated
• Inventors: Trsar, Dale A., Snorteland, Lee M., McQueeney, Kenneth A., Loewe, Thomas D.
• Primary Examiner(s): Assouad, Patrick J.
• Application Number:
  US10/695,806
• Publication Number:
  US 20050096868A1
• Time in Patent Office: 859 Days
• Field of Search: 73/350.1, 731/16, 731/171, 731/19.R, 702/182, 702/33, 702/41, 702/42, 702/117, 123/406.11, 123/406.13, 123/406.17
• US Class Current: 702/182
• CPC Class Codes: G01L 3/1478 involving hinged levers
• 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

Abstract

Engine cylinder contribution analysis is provided. An engine cylinder contribution tester includes a displacement measurement device and a signal analyzer. The displacement measurement device detects engine block movements or displacement relative to a fixed position caused by a poorly contributing cylinder. The displacement measurement device provides a displacement signal to the signal analyzer. The signal analyzer includes a cylinder contribution module for evaluating the displacement signal. If a particular cylinder is contributing less than the average of the other cylinders, the displacement signal indicates engine block movement associated with a lack of contribution from that cylinder.

Claims

1. A system for evaluating engine cylinder contribution comprising:

a displacement measurement device configured to detect engine block movement relative to a stationary structure; and

a signal analyzer coupled to the displacement measurement device and configured to evaluate the engine block movement for determining engine cylinder contribution,

wherein the displacement measurement device comprises a potentiometer having a shaft with a first end and a second end, wherein the first end is attached to the engine block and the second end is attached to the stationary structure.

2. A system for evaluating engine cylinder contribution comprising:

a displacement measurement device configured to detect engine block movement relative to a stationary structure; and

a signal analyzer coupled to the displacement measurement device and configured to evaluate the engine block movement for determining engine cylinder contribution, wherein the displacement measurement device comprises a machine vision device.

3. A method for measuring cylinder contribution for an engine having a firing order, the method comprising the steps of:

implementing a displacement measuring device for detecting engine block movement relative to a stationary structure;

correlating the engine block movement to the firing order; and

evaluating, for at least one engine cylinder, the engine block movement; and

further comprising;

attaching a first end of the displacement measuring device to the engine block; and

attaching a second end of the displacement measuring device to the stationary structure.

4. A method for measuring cylinder contribution for an engine having a firing order, the method comprising the steps of:

implementing a displacement measuring device for detecting engine block movement relative to a stationary structure;

correlating the engine block movement to the firing order; and

evaluating, for at least one engine cylinder, the engine block movement;

wherein the evaluating step further comprises;

determining a cylinder contribution from the engine block movement; and

the determining step includes computing a derivative of the engine block movement.