Remote tire and shock absorber monitor

• US 5,525,960 A
• Filed: 09/08/1993
• Issued: 06/11/1996
• Est. Priority Date: 09/08/1993
• Status: Expired due to Fees

• Current Assignee: Richard Mccall
• Original Assignee: Richard Mccall
• Inventors: Coad, Craig A., McCall, Richard E., Uland, Larry L.
• Primary Examiner(s): Peng, John K.
• Assistant Examiner(s): POPE, DARYL C
• Application Number:
  US08/117,799
• Time in Patent Office: 1,007 Days
• Field of Search: 340/438, 340/443, 73/146.5, 200/61.23, 200/61.24, 200/61.25, 200/61.26, 116/34 R
• US Class Current: 340/438
• CPC Class Codes: B60R 16/0232 for measuring vehicle parameters and indicating critical, abnormal or dangerous conditions

Abstract

A system for monitoring the steady state condition of a motor vehicle shock absorber is used to identify conditions in which a tire may be under- or over-inflated, or in which a shock absorber needs adjustment or replacing. A device for measuring distance, such as a measuring tape, is affixed along the length of a movable portion of a shock absorber, and is monitored by a shock absorber sensor, which is mounted in a fixed position relative to the measuring device. The vertical distance through which the movable portion of the shock absorber moves and the velocity of the oscillations of said movable portion is thereby monitored, and data is transmitted from the sensor to a circuit for transforming said data into a visual display for visual monitoring by the vehicle driver. Said data is further sent through a comparator circuit for comparing to other data received simultaneously from at least one other sensor similarly mounted in relation to another shock absorber of the vehicle. When the vertical distance or frequency oscillation data of a shock absorber sensor deviates beyond a predetermined threshold variance from the data of said other sensor, an alarm indicator is activated for encouraging the driver to check the air pressure and/or shock absorber of the particular tire(s) associated with the deviation.

Claims

1. A remote shock absorber monitor for monitoring a vertical oscillation frequency and for warning a vehicle driver that a vehicle shock absorber needs service, comprising,

a monitor for monitoring the vertical oscillation frequency of a movable portion of a shock absorber of the vehicle, wherein the monitor includes a plurality of indicia affixed to the movable portion of the shock absorber in a linear array coaxial with the movable portion, and

a sensor mounted to a fixed portion of the shock absorber for monitoring the vertical movement of the indicia relative to the fixed portion of the shock absorber.

2. The apparatus as recited in claim 1, wherein the linear array of indicia includes a pattern of alternating dark and light colored shapes for reflecting from the fixed portion of the linear array, relative to the fixed portion of the shock absorber, a pattern of light pulses having a pulse frequency corresponding to the vertical oscillation frequency of the movable portion.

3. The apparatus as recited in claim 2, wherein the sensor includes a photo-cell circuit and a frequency to voltage convertor circuit.

4. A remote shock absorber monitor for warning a vehicle driver that a vehicle shock absorber needs service, comprising:

a monitor base mounted to a fixed portion of the shock absorber and having an aperture therethrough, the aperture having an axis which is parallel to that of the shock absorber;

a photo-emitter for transmitting light in a direction perpendicular to the axis of the shock absorber;

a photo-sensor for sensing the light, the photo-emitter and photo-sensor being coplanar and mounted adjacent opposite edges of the monitor base aperture, such that the light is transmitted from the photo-emitter across the aperture to the photo-sensor;

a rod mounted to the shock absorber such that the axis of the rod is parallel to that of the shock absorber, the rod having at least one end affixed to the movable portion of the shock absorber for moving a main length of the rod through the monitor base aperture synchronistically with the movable portion of the shock absorber such that the main length traverses the light transmitted from the photo-emitter, the rod further including a linear array of uniform apertures therethrough, the linear array being coaxially aligned with the rod, and the axis of each of the apertures being coaxially aligned with the light transmitted from the photo-emitter for allowing the light to be transmitted to the photo-sensor through the apertures such that the photo-sensor receives from the photo-emitter a pattern of light pulses having a pulse frequency corresponding to the oscillation frequency of the shock absorber; and

a frequency to voltage convertor circuit electrically connected to the photo-sensor.

5. A remote shock absorber monitor for warning a vehicle driver that a vehicle shock absorber needs service, comprising,

a monitor for monitoring vertical displacement of a movable portion of a vehicle shock absorber, wherein the monitor is a linear variable differential transformer affixed to the shock absorber such that a rod in the transformer is affixed in a parallel relationship to a movable portion of the shock absorber and moves synchronistically with the movable portion, having a vertical displacement equivalent to that of the movable portion, thereby generating an electric signal indicative of the vertical displacement of the shock absorber;

and

a warning device, attached to the monitor, for warning the driver of the vehicle when the vertical displacement of one of the shock absorbers varies significantly from the vertical displacement of another shock absorber.