Data processing: measuring – calibrating – or testing – Measurement system – Orientation or position
Reexamination Certificate
2000-01-10
2001-12-04
Assouad, Patrick (Department: 2857)
Data processing: measuring, calibrating, or testing
Measurement system
Orientation or position
C033S288000, C356S139090
Reexamination Certificate
active
06327548
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to wheel alignment methods and devices and, more specifically, to a computer-assisted method for adjusting wheel alignment angles that allows easy access to wheel alignment adjustment points.
BACKGROUND OF THE INVENTION
Vehicle wheel aligners are well known in the art. Such aligners typically comprise a computer or processor operated in conjunction with a number of alignment heads, mountable relative to the wheels of a vehicle, and angle measuring instruments to measure the alignment characteristics of the vehicle. Examples of such vehicle wheel aligners can be found in U.S. Pat. Nos. 5,724,743 and 5,875,418, both of which are owned by the assignee hereof. The alignment heads of these vehicle wheel aligners are typically mounted to the rims of the wheels using wheel clamps. Examples of such wheel clamps can be found in U.S. Pat. Nos. 5,242,202 issued to Ettinger; 4,815,216 issued to Swayne; and 4,285,136 issued to Ragan, all of which are owned by the assignee hereof.
These conventional vehicle wheel aligners are capable of indicating the adjustments that must be performed to correct wheel misalignment. For example, the vehicle wheel aligner might indicate that the camber, an angular measure representing the inward or outward tilt of the wheel from a true vertical, is 1° and should be adjusted ½° to a final value of ½°. Likewise, the vehicle wheel aligner might indicate that the caster, an angular measure determined by the relationship of the upper ball joint to the lower ball joint or the upper pivot to the lower pivot in a forward and aft axis, which represents the forward or rearward tilt of the steering axis from a true vertical, is 2° and should be adjusted 1° to a final value of 1°.
However, access to the wheel alignment adjustment points to correct for the indicated deviations is often limited or restricted and it has therefore sometimes been necessary to remove the wheels and the alignment equipment, such as the alignment heads, to provide access to the wheel alignment adjustment points. This is evident, for example, in
FIG. 1
, which shows a cut-away view of a wheel (not numbered) mounted on a first configuration of vehicle suspension system components including a steering knuckle
10
of a spindle
20
movably attached to upper ball joint
12
and lower ball joint
14
, joining the spindle to the upper control arm
16
and the lower control arm
18
, respectively, as well as an upper control arm attachment
24
.
FIG. 2
shows a top view of a another configuration of vehicle suspension system components exposing the general relationship between a wheel
28
attached to a wheel mounting structure of a vehicle, an upper control arm
26
, vehicle suspension adjustment points
30
, and the vehicle frame
40
. Vehicle suspension adjustment points
30
can be adjusted, such as by shimpacks (not numbered) installed at the adjustment points
30
to displace the upper control arm laterally from the vehicle frame
40
.
FIG. 3
a
is a top view of a third configuration of vehicle suspension system components including an asymmetric control arm
50
attached to a spindle
52
and a wheel
54
.
FIG. 3
a
illustrates, for this asymmetric control arm
50
, an adjustment point
60
, for adjusting caster, and an adjustment point
70
, for adjusting camber.
FIG. 3
b
shows an isometric view of the asymmetric upper control arm of
FIG. 3
a,
showing the same vehicle suspension adjustment points
60
,
70
of
FIG. 3
a.
Thus, as shown by these examples, in many vehicle configurations the presence of the wheel impedes or prevents access to these, and other, adjustment points.
One conventional approach to access the vehicle suspension adjustment points involves removing the wheel alignment equipment and wheel following an initial reading, approximating the degree of the adjustment needed, executing the corresponding adjustments, reassembling of the wheel and measurement device, and remeasuring the alignment to determine if the adjustments are acceptable. However, this method is inexact and sometimes requires multiple iterations, involving considerable time.
In another conventional approach, alignment technicians remove the electronic measuring device and the wheel and substitute mechanical measuring devices, such as a level vial, to the hub to provide a visual indication of the degree of change. However, mechanical measuring devices are not as accurate as the electronic measuring device and, in the case of the level vial, the mechanical device is not suited for adjustments to caster.
In yet another conventional approach, alignment technicians simply leave the vehicle wheel alignment equipment in place and rely upon specialized tools, such as wrenches with particularized shapes and special pry bars, to compensate for the inaccessibility of the adjustment points. However, this approach requires a large inventory of specialized tools.
A need exists for an improved method of adjusting wheel alignment angles that provides enhanced access to wheel alignment adjustment points.
SUMMARY OF THE INVENTION
In accordance with the foregoing object, the present invention advantageously provides, in one preferred embodiment, a computer-assisted method for adjusting wheel alignment angles of a wheel attached to a wheel mounting structure of a vehicle. This method includes the steps of measuring a baseline wheel alignment angle with respect to a rim or hub of a wheel and using a computer for storing baseline wheel alignment angle data in a memory; determining from the baseline wheel alignment angle a required change in the wheel alignment angle; and removing the wheel and rim from the mounting structure. Further steps include using the computer to retrieve the baseline wheel alignment angle data from the memory; measuring a change in wheel alignment angle from the baseline wheel alignment angle while adjusting the mounting structure; and comparing the change in wheel alignment angle data and the required change in the wheel alignment angle. In this manner, removal of the wheel and rim from the mounting structure enables easy access to the alignment points, while simultaneously enabling the use of an electronic wheel alignment measuring device.
Another embodiment of the computer-assisted method for adjusting alignment angles of a wheel mounted to a wheel mounting structure of a vehicle includes the steps of receiving, by a computer, baseline measurements of a wheel alignment angle from a measurement device attached to a rim or hub of the vehicle and storing the baseline wheel alignment angle data in a memory; determining a required change a wheel alignment angle; prompting for removal, by a technician, of the rim and wheel from the mounting structure of the vehicle and for attaching a measurement device to the mounting structure; and prompting for adjustment, by the technician, of the wheel alignment angle in a direction of the required change. Further steps include receiving measurements of the change in wheel alignment angle measured by the measurement device attached to the mounting structure; and prompting the technician to stop adjusting the wheel alignment angle when the measured change in wheel alignment angle substantially corresponds to the required change.
In yet another embodiment, a computer-assisted wheel alignment system for adjusting alignment angles of a wheel attached to a wheel mounting structure of a vehicle, includes a processor; a memory storing reference wheel alignment data; a measuring device configured to be attached alternatively to (1) a rim or hub of a wheel to produce baseline wheel alignment angle data and (2) the wheel mounting structure to produce a change in wheel alignment angle data; and a data transmission path for carrying data between the measuring device and the processor, wherein the processor is programmed to produce output signal indicating a degree of difference between the baseline wheel alignment angle data and a change in wheel alignment angle data measured by the measurement device.
Addition
Assouad Patrick
McDermott & Will & Emery
Snap-on Technologies, Inc.
LandOfFree
Method of adjusting wheel alignment angles does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method of adjusting wheel alignment angles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of adjusting wheel alignment angles will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2588241