Process for the determination of unbalance

• US 5,058,428 A
• Filed: 11/06/1989
• Issued: 10/22/1991
• Est. Priority Date: 03/29/1986
• Status: Expired due to Fees

• Current Assignee: Schenck Rotec GmbH (Durr AG)
• Original Assignee: Schenck Auto-Service-Gerate GmbH
• Inventors: Guyot, Volker
• Primary Examiner(s): CHAPMAN JR, JOHN E
• Application Number:
  US07/432,058
• Time in Patent Office: 715 Days
• Field of Search: 73/457, 73/460, 73/462, 324/175
• US Class Current: 73/457
• CPC Class Codes: G01M 1/28 with special adaptations for determining imbalance of the body in situ, e.g. of vehicle wheels

Abstract

A method and apparatus is provided for determining the unbalance of the wheels of a motor vehicle under test by means of unbalance measuring equipment. Such equipment is operated with a d.c. voltage supply in the form of the battery of the vehicle under test which functions as the sole source of that supply. The driven wheels of the vehicle under test are accelarated by the vehicle engine until a constant wheel speed is obtained within a given range. The unbalance values of the driven wheels at constant wheel speed are determined and appropriate correction is made. Wheel driving structure may also be provided for rotating the non-driven wheels of the vehicle under test to determine the unbalance of these wheels. The wheel driving structure for rotating the non-driven wheels is also powered by a d.c. voltage source in the form of the vehicle battery.

Claims

1. A method of determining the out-of-balance effects of the wheels of a motor vehicle under test by means of out-of-balance measuring devices, oscillation converters and reference-mark scanning devices, the method comprising the steps of providing an out-of-balance measuring device, an oscillation converter and a reference-mark scanning device for each driven wheel of the vehicle under test, operating the out-of-balance measuring devices, oscillation converters and reference-mark sensors with a d.c. voltage supply and utilizing the battery of the vehicle under test as the sole source of that supply, rotating the driven wheels of the vehicle under test by accelerating the vehicle engine until a constant wheel speed is obtained within a given range, and determining that out-of-balance values of the driven wheels at the constant wheel speed.

2. A method as in claim 1 including the step of rotating each non-driven wheel of the vehicle until a constant wheel speed is obtained within a give range, and determining the out-of-balance values of the non-driven wheels of the vehicle with an out-of-balance measuring device, an oscillation converter and a reference mark scanning device all powered by a d.c. voltage supply, and wherein the vehicle battery is utilized as the sole source of that supply.

3. Apparatus for determining the out-of-balance effects on the wheels of a motor vehicle under test comprising an out-of-balance measuring device, an oscillation converter and a reference-mark scanning device for each vehicle wheel, driving means for rotating the non-driven wheels of the vehicle, both the vehicle under test and the driving means for the non-driven wheels of the vehicle each having a d.c. voltage source, each in the form of a separate battery, and electrical connection between the out-of-balance device, the oscillation converter, the reference-mark scanning device and the battery of the vehicle under test or the battery of the driving means for providing d.c. power thereto, and wherein each reference mark scanning device includes a housing (1) and at least one magnetic holding means (6) for mounting the housing (1), the housing (1) having an aperture (3) in a side (2) adjacent a motor-vehicle wheel under test, an optical transmitter and receiver within the housing beamed through the aperture (3), and the housing (1) having inspection apertures (4,5) in housing faces (17, 18) which faces are substantially parallel to one another and generally horizontally disposed.