Abstract:
Method and apparatus for elevating an object by a member secured to the object for the elevation thereof; and a mechanism for operating the elevation member, which can be positioned beneath the object, such as a vehicle, where the elevation member is a source of fluid pressure, which can be gaseous or hydraulic and is connected to the member for elevating the vehicle or a portion thereof such as a wheel.

Description:
FIELD OF THE INVENTION  
         [0001]    The invention relates to a wheel lift, and more specifically to a wheel lift for a vehicle.  
         BACKGROUND OF THE INVENTION  
         [0002]    It often is necessary to elevate an object such as a vehicle. This is typically the case where it becomes necessary to change a tire or otherwise have access to the underside of the vehicle, for example, to replace a defective part or to install an accessory.  
           [0003]    In the case of tire changing, it is common practice to employ a manual jack that is removed from the trunk compartment and placed under the frame of the vehicle in the vicinity of the item such as a tire to which access is desired.  
           [0004]    This approach to tire changing has many drawbacks. In the first place, when a tire defect occurs while a vehicle is in motion, it is necessary to pull off the roadway and seek a level area where the use of the ordinary jack will not cause difficulty. In addition, it is necessary for the operator of the vehicle to open the door and often face on-coming traffic with the possible consequence that the driver with a defective tire will be struck by a passing vehicle while in the course of removing the jack from its storage compartment and then attempting to jack up the vehicle.  
           [0005]    Not only are there traffic hazards, but the jack must be properly positioned with respect to the frame, otherwise the vehicle can become damaged during the jacking operation and in some cases, give rise to an instability that may cause the vehicle to fall after its been jacked.  
           [0006]    As an alternative to having the driver or occupant of a vehicle attempt to elevate a tire that needs changing, a call can be made to a service organization that can avoid the foregoing difficulties by employing a hydraulic jack to properly elevate the wheel.  
           [0007]    Unfortunately, before use can be made of the hydraulic jack on a service vehicle, it usually is necessary to have precise alignment between the service vehicle and the vehicle being served. In crowded lots and along curbsides, where heavy traffic restricts movement, the ordinary service vehicle lift proves to be cumbersome and fails to give the operator sufficient flexibility.  
           [0008]    Further, the ordinary designs are not adapted to provide fully automatic connections, thus forcing the driver of the service vehicle to leave the cab to elevate the wheel.  
           [0009]    Peterson, U.S. Pat. No. 3,484,817 discloses a lift which employs manually deployable fork elements. In operation, a lift-boom is lowered and a wheel fork is manually unfolded. Support rods, located at the distal ends of the fork, are then manually removed from the fork, to surround the wheel. In this position, the support rods are replaced, forming rectangular frames whose longitudinal sides are shorter than the diameter of the tire. The forks and vehicle are then raised. The forks, however, must be precisely aligned with the tire, requiring the operator to back up the forks within about a half-foot from the center line of the tires. Further, the tow operation requires at least three manual steps: two before the wheels are engaged and one after the wheel has been engaged.  
           [0010]    Haring, U.S. Pat. No. 4,034,873 discloses a sling which can be placed under a tire by abutting a pair of slant bars next to the tire and by then securing the bars to the tires by a pair of adjustable bars. As a result, a cradle is formed about the tire when being raised. Therefore, the operation is both time-consuming and may require more than one operator.  
           [0011]    Young Blood, U.S. Pat. No. 4,186,938, discloses a lift arrangement which requires attachment of a bar directly to the frame of the vehicle. The bar must be manually attached to the vehicle and requires precise alignment with the vehicle frame in order to place the ends of the bar in direct communication with holes in the frame. Young Blood, as a result, also requires precise alignment and may need two operators to achieve alignment. Young Blood does not benefit from attaching a connection to a point where the suspension system of the vehicle can be used as a shock absorber.  
           [0012]    Prior art vehicle wheel lift devices require complex or difficult maneuvers to correctly align the vehicle lift system, or entail manual manipulation to securely connect the apparatus to the vehicle.  
           [0013]    Accordingly, it is an object of the invention to overcome the deficiencies of the prior art by providing a wheel lift which can be easily operated.  
           [0014]    Another object of the invention is to facilitate the elevation of an object such as a vehicle, particularly where it becomes necessary to change a tire or otherwise have access to the underside of the vehicle, for example, to replace a defective part or to install an accessory.  
           [0015]    A further object of the invention is to avoid the need for to employ a manual jack that has to be removed from a trunk or other compartment and placed under the frame of the vehicle, in the vicinity of the item such as a tire to which access is desired.  
           [0016]    A still further object of the invention is to avoid the need when a tire defect occurs while a vehicle is in motion, to pull off the roadway and seek a level area where the use of the ordinary jack will not cause difficulty. A related object is to avoid the need for the operator of the vehicle to open the door and often face on-coming traffic with the possible consequence that the driver with a defective tire will be struck by a passing vehicle while in the course of removing the jack from its storage compartment and then attempting to jack up the vehicle.  
           [0017]    Another object of the invention is to avoid the need for having the jack properly positioned with respect to the frame, so that the vehicle cannot become damaged during the jacking operation, and in some cases, give rise to an instability that may cause the vehicle to fall after its been jacked.  
           [0018]    Still another object of the invention is to avoid having the driver or occupant of a vehicle attempt to elevate a tire that needs changing by making a call to a service organization to employ a jack to properly elevate the wheel. A related object is to avoid the need, before use can be made of the jack on a service vehicle, of the necessity to have precise alignment between the service vehicle and the vehicle being served. In crowded lots and along curbsides, where heavy traffic restricts movement, the ordinary service vehicle lift proves to be cumbersome and fails to give the operator sufficient flexibility.  
           [0019]    A further object of the invention is to avoid the need for having the driver of the service vehicle to leave the cab to elevate the wheel. A related object is to avoid the difficulties associated with Peterson, U.S. Pat. No. 3,484,817 which discloses a lift employing manually deployable fork elements. The forks must be precisely aligned with the tire, requiring the operator to back up the forks within about a half-foot from the center line of the tires. Further, the tow operation requires at least three manual steps: two before the wheels are engaged and one after the wheel has been engaged.  
           [0020]    A still further object of the invention is to avoid the difficulties associated with Haring, U.S. Pat. No. 4,034,873 which discloses a sling that can be placed under a tire by abutting a pair of slant bars next to the tire and by then securing the bars to the tires by a pair of adjustable bars. As a result, a cradle is formed about the tire when being raised. Therefore, the operation is both time-consuming and may require more than one operator.  
           [0021]    Yet another object of the invention is avoid the difficulties associated with Young Blood, U.S. Pat. No. 4,186,938, which discloses a lift arrangement that requires attachment of a bar directly to the frame of the vehicle. The bar must be manually attached to the vehicle and requires precise alignment with the vehicle frame in order to place the ends of the bar in direct communication with holes in the frame. Young Blood, as a result, also requires precise alignment and may need two operators to achieve alignment. Young Blood does not benefit from attaching a connection to a point where the suspension system of the vehicle can be used as a shock absorber.  
           [0022]    Prior art vehicle wheel lift devices require complex or difficult maneuvers to correctly align the vehicle lift system, or entail manual manipulation to securely connect the apparatus to the vehicle.  
         SUMMARY OF THE INVENTION  
         [0023]    In accomplishing the foregoing and related objects, the invention provides for elevating an object by a mechanism secured to the object for the elevation thereof, and for operating the elevating mechanism.  
           [0024]    In accordance with one aspect of the invention, the elevating mechanism is positioned beneath the object, which can be a vehicle.  
           [0025]    In accordance with another aspect of the invention, the elevating mechanism is operated from a source of fluid pressure, which can be gaseous or liquidic, such as hydraulic.  
           [0026]    In accordance with a further aspect of the invention the source of fluid pressure is connected to a device for elevating the vehicle, and more particularly fluid pressure is applied to said elevating mechanism in order to elevate a wheel of the vehicle. The source of fluid pressure can be rechargeable.  
           [0027]    In a method of the invention for elevating an object the steps include (a) securing to the object a mechanism for the elevation thereof; and (b) operating the elevation mechanism. The invention further includes the step of positioning the elevation mechanism beneath the object and attaching the elevation mechanism beneath the vehicle.  
           [0028]    The invention also includes the step of providing the elevation mechanism with a source of fluid pressure that can be gaseous, fluidic or hydraulic. The source of fluid pressure is connected to a device for elevating the vehicle, such as a wheel thereof. Fluid pressure is applied to the elevating mechanism in order to elevate a wheel of the vehicle, and the fluid source is rechargeable.  
           [0029]    In a method of the invention providing for the repair of a flat tire on a vehicle, the steps include: (a) loosening the flat tire from the vehicle; (b) elevating the tire by a mechanism at a fixed position beneath the vehicle for the elevation of the flat tire; (c) Removing the flat tire from the vehicle at the elevated position of the tire; (d) replacing the flat tire by a suitably inflated tire on the vehicle; and (e) lowering the inflated tire by the mechanism at the fixed position beneath the vehicle. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]    Various other features, advantages and characteristics of the invention will become apparent after considering several illustrative embodiments, taken in conjunction with the drawings, in which:  
         [0031]    [0031]FIG. 1 is a perspective view of a vehicle for which the left front tire has been elevated by a fluid actuated jack fixed beneath the vehicle and operated from within the vehicle.  
         [0032]    [0032]FIG. 2A is an underside view of the chassis of the vehicle of FIG. 1, showing illustrative components by which the vehicle can be elevated from controls located within the vehicle.  
         [0033]    [0033]FIG. 2B is an underside view of the chassis of the vehicle of FIG. 1, showing alternative components by which individual wheels of the vehicle can be elevated from controls located within the vehicle.  
         [0034]    [0034]FIG. 2C is a view illustrating the use of a lug gun operated from the components beneath the chassis for removing a flat tire from the vehicle.  
         [0035]    [0035]FIG. 3A is a cross-sectional view of an illustrative lift mechanism in accordance with the invention.  
         [0036]    [0036]FIG. 3B is a cross-sectional view of the lift mechanism of FIG. 3A in operative position.  
         [0037]    [0037]FIG. 3C is an alternative lift mechanism in accordance with the invention.  
         [0038]    [0038]FIG. 4A is an expanded view of the lift valve control of FIG. 2A.  
         [0039]    [0039]FIG. 4B is an expanded view of an illustrative valve control mechanism for FIG. 2B.  
         [0040]    [0040]FIG. 5 is a schematic of the driver actuatable controls of FIG. 1.  
     
    
     DETAILED DESCRIPTION  
       [0041]    With reference to the drawings, in FIG. 1 the left front tire  11  of a vehicle  10  has been elevated by a fluid actuated jack system  20  that is at a fixed position beneath the vehicle  10  and operated from within the vehicle by driver actuatable controls  30 .  
         [0042]    As shown in FIG. 2A, the underside chassis of the vehicle of FIG. 1, includes the illustrative components of the fluid actuated jack system  20  by which the vehicle  10  can be elevated from the controls  30  located within the vehicle  10 . The system  20  is formed by a fluid pressure tank  21  which extends to a front lift mechanism  22  and to a rear lift mechanism  23 . In addition, an outlet valve  24  permits access to the pressure tank  21  for auxiliary uses of pressure, for example, by permitting the operation of a lug gun  50 , as illustrated in FIG. 2C, by which the lug bolts of a conventionally mounted tire can be loosened preparatory to operation of the lift mechanism and by completely removing the loosened lug nuts after a wheel has been elevated.  
         [0043]    The pressure tank  21  is connected to the front lift  22  through a lift valve control  25  and a similar lift valve control  26  connects the pressure tank  21  to the rear lift  23 . The lift valve controls  25  and  26  are operated from within the vehicle  10  by the driver actuatable controls  30 , illustrated in FIG. 5.  
         [0044]    In an illustrative embodiment of the invention for elevating a vehicle weighing approximately 3500 lbs., the pressure tank  21  can exert pressure on the order of about 150 lbs./ square inch to realize 850 lbs. of lift at each tire position.  
         [0045]    In FIG. 2A, the front lift mechanism  22  can be used to elevate the entire front portion of the vehicle  10 , while the rear lift mechanism  23  is used to lift the entire rear portion of the vehicle  10 . Where it is desired to provide for individual lifts of the vehicular wheels, the arrangement of FIG. 2B can be employed showing an underside view of the chassis of the vehicle  10  of FIG. 1, with alternative components by which individual wheels of the vehicle  10  can be elevated from controls  30  located within the vehicle  10 .  
         [0046]    The frontal lift mechanism  22  has been replaced by individual lift devices  27 A and  27 B for the right front wheel  12 A and the left front wheel  12 B. Similarly, the rear lift mechanism  23  has been replaced by individual lift devices  28 A and  28 B for the right rear wheel  13 A and the left rear wheel  13 B.  
         [0047]    In FIG. 3A the cross-sectional view of an illustrative lift device  26 A, B or  27 A, B takes the form of a cylindrical system  40  with a shell  41  enclosing a piston  42  and a lift rod  43  that is acted upon by fluid pressure P that enters a cylindrical chamber  44 , as shown in FIG. 3B, above the head  42 H of the piston  42 , which is sealed from the shell  41  by rings  42 R. The piston  42  and the lift rod  43  are held in their elevated position by a spring  45  that is compressed when fluid P enters the chamber  44 , after a signal is received from the controls  30 . As a result, the lift rod  43  is extended so that a wheel  12 A, B or  13 A, B is elevated to permit use of the lug gun  50  at the connector  24  to complete removal of the lug nuts by which the wheel is mounted on the vehicle  10 .  
         [0048]    After an inflated replacement tire is positioned where the wheel  12 A has been removed, the lift rod  43  returns to its original position within the cylinder  40  by the expansion of the spring  45 .  
         [0049]    In FIG. 3C, the cross-sectional view of an alternative lift device  60  in accordance with the invention provides for return of the lift rod  43  by omitting the spring  45  of FIGS. 3A and 3B, and instead using a bypass channel  61  to apply return fluid pressure to the piston  42  between a flange  62  that surrounds the lift rod  43  near the exit position of the device  60  and is slidably sealed to the lift rod  43  by a grommet  63  fixed to the flange  62 .  
         [0050]    The control panel  30  mounted within the vehicle  10  to permit driver operation of the lift structures takes the form of fluid control connections F 1 -F 4  and R 1 -R 4  that are operated by buttons BF 1 -BF 4  and BR 1 -BR 4 . When the button BF 1  is pressed, it closes switch SF 1  and the remaining buttons close counterpart switches SF 2 -SF 4  and SR 1 -SR 4 . Closure of any switch applies a signal from the connected battery B of FIG. 5 to a lift valve control, thus the lift valve control  25  of FIG. 4A can be operated by switches SF 1  and SR 1 . The signal from closure of SF 1  closes a switch SC 1  that permits the application of fluid pressure while a signal from closure of SR 1  opens a switch SC 2  and permits the return of fluid to the pressure tank  21  from the lift  22 .  
         [0051]    Where individual lifts such as  27 A and  27 B are employed, the control can take the form shown in FIG. 4B, where the lift controls  27 A and  27 B have been combined into a single unit.  
         [0052]    Thus, an arrangement is made for permitting the control flow of pressure from the tank  21  to the lift mechanisms and release of pressure when the lift rod  43  is to be returned by spring action or by providing an alternative line to apply return fluid pressure when the spring  45  is not used.  
         [0053]    In the case of comparatively large vehicles, such as trucks, the vehicles have installed compressors, which are used or are incorporated into the pressure tank  21  of FIG. 2A. For some vehicles the installed compressors can provide over 100 pounds per square inch of pressure and the compressor can be integrated into the pressure tank and be operated by a motorized arrangement (not shown).  
         [0054]    In addition, the lift rods shown in FIGS.  3 A- 3 C are in rod form but also can be arranged to be formed in telescopic segments that can be extended for lifting and retracted after the lift operation has been completed.  
         [0055]    It is to be understood that the foregoing description is illustrative only and that modifications and adaptations of the invention, including, but not limited to, the use of equivalents, may be made by those of ordinary skill in the art without departing from the spirit and scope of the invention as defined in the appended claims.