The present invention relates to gauges for detecting and analyzing damage to vehicles.
With the increased use of highways by vehicles, the number of collisions between vehicles or between vehicles and objects has increased greatly. Frequently in such collisions, it is not only the vehicle body that is mangled and twisted, but also the frame member or chassis on which the vehicle body is supported. At times, the only damage done to an automobile is noticeable and obvious, such as damage done to the fender, bumper, grill and headlight. However, if the frame of the vehicle has been damaged by the collision, the effect of such damage is not easily noticed or corrected. Different types of collisions produce different types of damage to the chassis of a vehicle. For example, a collision that results in one vehicle being hit broadside by another will, in most instances, result in the mid-portion of the frame or chassis between front and rear wheels being pushed inwardly toward the opposite frame member. On the other hand, collisions in which the front or rear corners of the frame receives the impact of the collision will frequently result in the frame being wrenched out of alignment so that the front and rear wheels do not track. Obviously, some collisions result in both types of damage to the chassis, the chassis being bent and twisted simultaneously. If frame member damage is not detected and repaired, chronic problems with steering, front end wear or even rear end wear will result. In addition, damage is difficult to pinpoint in vehicles built with unit body construction which is deemed to be a predominant type of construction in the future. Further, many collisions cause altering of the mounting positions for the front suspension units.
Several known methods exist for detecting the damage done to a vehicle which has been involved in a collision. These methods usually make some form of comparing a damaged portion of the vehicle to a supposedly undamaged, symmetrical portion of the vehicle. This comparison requires not only exact dimensioning, but also diagnostic decision making. Once the damage is detected, various straightening or pulling procedures are enacted. Many auto body personnel treat the actual physical act of pulling damage as the primary effort in body repair and fail to properly and completely analyze the damaged vehicle. Correct analysis is essential and must be done before pulling starts. To repair a damaged vehicle properly, the damage must be pulled out simultaneously and exactly in reverse to the manner in which the damage was inflicted.
In one known method for detecting damage to an automobile, the vehicle is usually inspected where, without the use of any tools, a visual comparison between a damaged and a supposed undamaged portion of the vehicle is made. In another method known as reference dimensioning, actual measurements are taken from the undamaged portions of the vehicle. These measurements are then used to determine the correct position for identical, damaged portions. However, if the damage is not localized, these procedures result in improper repair due to distortion at the starting reference of the vehicle.
Various types of frame gauges are also known. These gauges permit measurement of the vertical distance of various parts of the undersurface of a vehicle from a reference horizontal plane, a datum plane, located beneath the vehicle. These measurements may be compared with reference values in body frame dimension figures made available by automobile manufacturers. An exemplary frame gauge is described in U.S. Pat. No. 3,869,804. However, these frame gauges do not permit analysis of other portions of a damaged vehicle such as the front, back, side and upper surfaces.