Patent Abstract:
A portable, light weight device for determining the toe in alignment of a wheel on a motor vehicle in which a base plate functions in cooperation with a slide which has limited transverse movement relative to said base plate, the movement being generated by the position of the slide relative to the toe in of a tire as it moves across the alignment device.

Full Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The “toe alignment” of the front or rear wheels of a vehicle is defined as the angular relationship of the principal plane of the front or rear wheels to the vertical plane passing through the longitudinal axis of the vehicle.  
         [0003]     It is imperative, from a safety standpoint that the “toe in alignment” be within tolerance to assure driving stability, increased tire life and reduced fuel consumption because of reduced friction. Nonetheless, it is a common occurrence that one runs over a pot hole or hits a curb, the consequence being a potential misalignment, including toe in.  
         [0004]     It is acknowledged that it is impractical for most vehicle owners to own or operate an expensive alignment device. Indeed, such devices are found almost exclusively in professional shops. It is still essential to keep a check on “toe” since this is the most common failure of alignment. The question becomes one of how does the average, non professional, determine, at minimal cost, that his or her vehicle is out of alignment.  
         [0005]     Overview of the Applicable Art  
         [0006]     There has been found no device which is affordable and useable by an average, non professional driver to determine the existence of an alignment problem. There are, of course, devices such as that depicted in Bennett U.S. Pat. No. 1,675,481, in which a plurality of balls  15  separate upper and lower runner boards. A vehicle is driven on to the upper board where the alignment of each wheel is measured in turn. The Bennett device is clearly a professional device and far to sophisticated and expensive to be found in one&#39;s garage at home.  
         [0007]     There are several such, obviously professional, devices which inhabit professional shops, but there is no known device available to the average motorist, at least until the advent of the present invention.  
       SUMMARY OF THE INVENTION  
       [0008]     The present invention relates, in a general sense, to a home testing device for determining the toe in of each wheel of a motor vehicle.  
         [0009]     It is an objective of the present invention to provide a motorist, consumer with such a device which technically understandable, and readily useable by a motorist with minimal to no experience in such testing devices.  
         [0010]     It is another objective, related to the foregoing, to provide a light weight, easily maintained, home testing device of the type described which is sufficiently inexpensive as to make it readily available to the average motorist, even one of modest resources.  
         [0011]     In summary, the overall object of this invention is to give a portable, durable, inexpensive, convenient and simple means by which the operator of a vehicle can check the “toe in” of a vehicle at their convenience, and at home.  
         [0012]     In the scheme of things, probably the single most important object of this invention is its simplicity of use, which can be understood by anyone who operates a vehicle. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]      FIG. 1 , is an exploded view, in perspective, of a portable toe in testing device constructed in accordance with the present invention;  
         [0014]      FIG. 2 , is a perspective view of the device of  FIG. 1 , shown assembled and ready for use; and  
         [0015]      FIG. 3 , is a partial sectional view of the device of  FIG. 2 , taken along lines A-A;  
         [0016]      FIG. 4  is an exploded view, in perspective, of a slightly modified embodiment of the present invention;  
         [0017]      FIG. 5  is an assembled perspective view of the modified form of the invention as shown in  FIG. 4 ; and,  
         [0018]      FIG. 6  is a partial sectional view taken along lines B-B of  FIG. 5 , illustrating the interrelationship between the slide and the end plates thereof.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0019]     With reference now to the drawings, and initially to  FIG. 1 , a portable toe in testing device is illustrated at  10 .  
         [0020]     The testing device  10 , in its most simple form, comprises a base plate  12 . A slide, in the nature of the plate  14  is provided and is adapted to overlay the base plate  12 . The surfaces of both plates are coated, or otherwise made of a low friction material, e.g., Teflon® or nylon®, although any material that meets the essential low friction criteria is within the contemplation of the invention.  
         [0021]     The base plate  12  is formed or affixed with end plates  16  and  18  respectively. The end plates are notched at  19  so as to partially overlay the free surface  21  of the base plate, and when the slide is inserted the notches restrict its movement to a transverse direction, inhibiting movement along its longitudinal axis.  
         [0022]     In order that a surface of the slide  14  can rest on the surface  21  with its motion relative thereto limited to transverse movement only, the ends  23  and  25  respectively of the slide are beveled, thus permitting the slide to be slipped under the end plates  16  and  18 , within the notches  19  with sufficient clearance to permit the slide  14  to move in a direction transverse to the longitudinal axis of the testing device, while inhibiting movement along that axis. The end plates serve as ramps as at  27  in order that a wheel can be readily driven over the device.  
         [0023]     A gauge  28  is mounted in the end piece  16 , where it senses movement of the slide as the vehicle is moved longitudinally, first across end piece  16  and continuing its movement across end piece  18  and away from the device. The needle  31  of the gauge  28  will set at its position of maximum deflection, thereby indicating the toe in of the wheel which has just moved across the testing device  10 .  
         [0024]     A transverse slot  34  is centrally disposed in the base plate and a fastener  36  is inserted through the slide and is secured in the slot  34  with sufficient, but limited, play as to permit the ready transverse movement of the slide relative to the base while holding the two together. It has been found that limited movement of about one-half inch is sufficient.  
         [0025]      FIGS. 4 through 6  illustrate a slightly modified relationship between the base plate  12  and slider  14 . In this modified form, the end plates  16  and  18  are not notched as they were in the  FIG. 1  embodiment at  19 , but simply squared off.  
         [0026]     In the  FIG. 4  embodiment, the slider is fashioned with at least four slots  40 . It will be seen that the orientation of the slots is transverse to the longitudinal axis of the portable toe in alignment device, each of the slots  40  being aligned in the same direction, i.e., transverse to the longitudinal axis of the device. The slots are uniformly spaced near the far corners of the plate, although the specific orientation may vary.  
         [0027]     Fasteners  42  are fitted with shims  44  and are fitted through the slots and into the base plate wherein fastener receptacles  46  are fitted.  
         [0028]     In the operation of each embodiment, the slide will move to the left or right and hold its adjusted position as the vehicle drives over the alignment device. The  FIG. 4  embodiment provides for slightly less friction with the end plates  16  and  18  than would be existing in the  FIG. 1  embodiment, although both devices will provide the user with a reading of the alignment of each wheel that is driven over the device.  
         [0029]      FIGS. 1 and 4  graphically illustrate the simplicity of using the alignment device. Initially, the operator of a vehicle simply drives straight and slowing across the device, then stops the car and picks up the light weight device  10  to read the results. If the gage  28  remains on center, it can be construed that the “toe in” of the car is according to specification. If the needle  31  of the gauge  28  has moved, the “toe in” is is either in or out, as the needle so indicates.  
         [0030]     It will be appreciated that the precise number of fasteners in either the  FIG. 1  or  FIG. 4  devices may vary without departure from the invention.  
         [0031]     While I have described successful structures for constructing my invention, it is possible in the art to make various modifications and still achieve the results desired, without departure from the invention as outlined in the claims below.

Technology Classification (CPC): 6