Abstract:
A fixture is provided for supporting a vehicle hub assembly during manufacturing operations that include rotating the assembly. The fixture includes a base with an upper surface, a linearly movable housing slidably supported on the base, an adjustable support block defining two selectable bores, each for slidably receiving a stud from one of two corresponding hub assembly types, and a handle for sliding the housing along the base. An operator checks the type of hub assembly to be worked on and rotates the support block if necessary to select the proper bore. The operator then slides the housing, causing the bore in the support block to slidably engage the stud. Each bore is configured within the support block so as to be accurately aligned with a stud on a corresponding hub assembly when supported in a jig, thus, allowing repeated fixture and hub assembly engagement without any additional adjustments.

Description:
BACKGROUND OF THE INVENTION 
   Fixtures have been used for years on assembly lines and workbenches to increase manufacturing speeds, and as a result overall productivity. Typical fixtures aid, for example, in welding, brazing, screw attachment and sub assembly installation processes. In operations where the part being manipulated is heavy, fixtures play an additional role of providing support. This support is important to prevent injury to workers performing assembly operations. An assembly worker who can avoid prolonged movement of heavy objects or having to significantly change position (through crouching, reaching, etc.) is less apt to become injured on the job. 
   One drawback inherent to fixtures is added clutter in the manufacturing area due to the presence of the fixture. Additionally, the part being manipulated must be loaded into and out of the fixture, preferably with little time and effort. The most efficient fixtures are small and can be loaded and unloaded very quickly. In order to maximize the efficiency of assembly lines, often more than one product model is assembled on a single assembly line. Thus, fixtures that can support multiple sized or shaped parts with little or no additional set up time are preferred. 
   Automobile manufacture utilizes assembly lines extensively. The assembly lines often support more than one type of vehicle. Additionally, vehicle components are often heavy and difficult to move or shift in order to complete operations thereon. What is desired in the present case is an efficient fixture for use in supporting the hub assembly of a vehicle so the hub assembly may be moved between multiple positions. The fixture, itself, should be easily moved from a use position to a position of non-use and moved out of the assembly area if desired. 
   BRIEF SUMMARY OF THE INVENTION 
   The present invention satisfies the requirements indicated above. The fixture of the present invention provides an easily adjustable device wherein the appropriate position of a support block on the fixture may be placed in line with a stud on a vehicle hub assembly. As a result, a single fixture of the present invention can be used on different vehicle types. 
   In accordance with the present invention, a fixture for supporting a vehicle hub assembly moved between multiple positions is provided and includes a base having an upper surface, a linearly movable housing, slidably supported on the base, an adjustable support block supported by the movable housing, the support block defining one or more bores for slidably receiving different sized studs from different hub assembly types, and a handle for assisting in slidably moving the housing along the base. 
   In accordance with a method of using the inventive fixture, the vehicle hub assembly is put in place on a common jig with the fixture when the fixture is in a retracted position. The operator then moves the fixture into an engaging position by grasping the handle on the fixture and slidably moving the housing until the fixture support block fits over the stud on the hub assembly, preferably the rear hub assembly of the vehicle. The hub assembly can then be rotated about the stud, as needed, to perform operations such as tightening fasteners located in different positions on the hub assembly. 
   These and other features, aspects and advantages of the present invention will be fully described by the following description, appended claims, and accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE FIGURES 
       FIG. 1  is a first perspective view of a hub assembly and fixture attached to an assembly line jig; 
       FIG. 2  is a perspective view of the fixture of the present invention; 
       FIG. 3  is a cross sectional view of the fixture in a disengaged position; 
       FIG. 4  is a cross sectional view across the width of the fixture; 
       FIG. 5  is a cross sectional view of the fixture in an engaged position; 
       FIG. 6  is a perspective view of the fixture showing adjustment of the support block; and 
       FIG. 7  is a second perspective view of a hub assembly and fixture attached to an assembly line jig; 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Referring to the drawings, a preferred slide assembly fixture  20  according to the present invention is illustrated. The fixture  20  includes a reconfigurable support block  22  supported on a linearly movable housing  24  that allows the support block  22  to be placed around and easily removed from a stud  102  upon the hub assembly  100  of a vehicle during vehicle manufacture. As described in more detail below, the fixture  20  additionally includes a base  26 , a handle  28  for moving the housing  24 , and a locking pin  30  for holding the support block  22  in a desired configuration. 
   Referring to  FIGS. 1 and 2 , the base  26  is formed from a generally rectangular plate including mounting holes  32  and a channel  36 . The plate is provided with four counter sunk mounting holes  32  that extend therethrough. The holes  32  preferably are transverse slots, as illustrated, to provide for an ability to adjust the position of the fixture  20 . Bolts are placed through the holes  32  to mount the fixture  20  to a jig  104  or other support when in use. The base  26  also includes a linear channel  36  proceeding along the length of the base  26  and centered across the width of the base  26 . The channel  36  has a narrow width at an upper surface  38  of the base, but widens laterally via a step approximately halfway through the thickness of the base  26 , forming the shape of an inverted “T”. The channel  36  extends from a first end  35 , along the length of the base  26 , to a point  42  a short distance from a second end  37  of the base  26 . The channel  36  is a guide for a flange  40  (see  FIG. 4 ) on the linearly movable housing  24  that is slidably received within the channel  36 . An end cap  44  is fixed to the first end  35  of the base  26  close the open end of the channel and thereby retaining the base  26 . 
   Referring to  FIGS. 4 ,  5  and  6 , the housing  24  is preferably formed in two sections, a slider  46  and a frame  48 . The slider  46  is a generally rectangular plate having a flat bottom  50  from which the flange  40  projects. The flat bottom  50  of the slider is smooth permitting the slider  46  to easily move over the upper surface  38  of the base  26 . The slider  46  defines four apertures  52  through its thickness. The apertures  52  are threaded, allowing screws  54  to hold the slider  46  and frame  48  together. The flange  40  has a narrow vertical post  56  and a wider crosspiece  58  on a side of the vertical post  56  opposite from the slider plate  46 . The flange  40  extends the full length of the slider  46  and, has an inverted “T” shape, matching the shape of the accommodating channel  36 . The crosspiece  58  of the flange  40  is preferably rounded at one end to allow easy assembly of the housing  24  into the base  26 . 
   Referring to  FIGS. 5 and 6  the frame  48  of the housing  24  is also rectangular shaped, in general, and fits directly over the slider  46 . The frame  48  defines three sections  60 ,  62 ,  64  of varying heights or thickness along its length. At a first end is a first section  60  of narrow thickness. The first section  60  defines two transverse slots  66  and  67  that are aligned across the width of the first section  60  and that terminate at opposite sides of the frame  48 . The slots  66 ,  67  provide a seat for the screws  54  that hold that slider  46  and frame  48  together and allow passage of the screws  54  therethrough. The slots  66 ,  67  may instead be holes. The second section  62 , adjacent to the first section  60 , defines a large central bore  68  through the thickness of the second section  62 . The second section  62  also defines a second bore  70  extending from one side of the second section  62  to the central bore  68 . A narrow raised ridge  72  protrudes from the edge of second section  62  immediately adjacent to the first section  60  and runs the width of the second section  62 . 
   The third section  64  is adjacent to the second section  62  and has a thickness slightly greater than the second section  62 . The third section  64 , like the first section  60 , defines first and second transverse slots  74 ,  75  that are aligned across the width of the third section  64  and terminate at opposite sides of the frame  48 . The third section  64  also defines a third slot  76 , perpendicular to the two transverse slots  74 ,  75  and that terminates at an end of the frame  48 . An aperture  78  is formed in the third section  64  of the frame  48  extending from an inner surface of the first transverse slot  74  to an inner surface of the second transverse slot  75  and intersecting the third slot  76 . The aperture  78  receives a pin  80  that pivotally secures the handle  28  to the housing  24 . The width of the frame  48  is slightly reduced on a first side  82  of the third section  64 . The first side  82  of the third section  64  is machined to produce a section of reduced width. The top edge  86  of the third section  64 , in this area of reduced width, is beveled. The area of reduced width  82  of the frame  48  extends from the third section  64  into the adjacent second section  62 . 
   Preferably the three sections  60 ,  62  and  64  of the frame  48  are form from a single piece of material. 
   The handle  28  is a long generally rectangular member including transverse apertures at each end thereof and a cross pin. A transverse aperture  88  is defined at a first end  92  of the handle  28  and receives a cross pin  90  that is grasped by a user. The first end  92  of the handle is rounded and a notch  94  is removed from the bottom of the first end. The notch  94  allows the housing to be locked in a position engaged with the hub assembly. Referring to  FIG. 3 , a transverse aperture  96  is defined at the second end  98  of the handle  28  as well and a notch  108  is also removed from the bottom of the second end  98 . The top edge of the second end  98  of the handle  28  is rounded. The aperture  96  in the second end  98  of the handle  28  holds the pin  80 , described above, that is received in the aperture  78  in the third section  64  of the frame  48 . 
   Referring to  FIGS. 3 and 6 , the support block  22  has, in general, a cube shape with an additional circular post  110  protruding from the bottom on the cube. The edges  112  constituting the upper perimeter of the cube are beveled. A first bore  114  is defined transversely through two opposite sides of the cube. The first bore  114  is sized to closely receive a first stud  102  from the hub assembly  100  of a specific vehicle model. A second bore  116  is defined transversely through the remaining two opposite sides of the cube. The second bore  116  is sized to closely receive a second stud from the hub assembly of a second, different type of vehicle. The first and second bores  114  and  116  have different diameters and are located at different heights on the support block so as to be properly aligned with the associated studs. Two locking bores  118  are also defined within the post  110  of the support block  22 . The locking bores  118  extend radially through the post  110  and are aligned with axes passing through the first and second bores,  114  and  116  respectively, in the cube portion of the support block  22 . 
   The locking pin  30  is a cylindrical shaped piece having first and second sections  120 ,  122  with different diameters. The first section  120  is at a distal end of the pin  30 , and is grasped by the user and may include a knurled surface. The second section  122  has a smaller diameter and is smooth so the locking pin may be smoothly inserted into the locking bore  118  on the post  110  of the support block  22 . 
   Referring to  FIG. 1 , the hub assembly  100 , preferably the rear hub assembly, is a structure, typically on an automobile, that is well known in the art and supports one of the two rear wheels on the automobile. 
   Referring to  FIGS. 2 and 5 , to assemble the fixture  20  of the present invention, the handle  28  is attached to the frame  48  by fitting the pin  80  through the aperture  78  in the third section  64 . The cross pin  90  is also placed through the aperture  88  of the handle  28 . The frame  48  is then fixed to the slider  46  using four screws  54 . The end cap  44  is removed from the base  26  and the housing  24  slid into place. Specifically, the flange  40  on the housing  24  is fit into the channel  36  of the base  26 . The end cap  44  is then replaced on the base  26 . The support block  22  is then fitted into the housing  24 . The support block  22  fits between the raised ridge  72  of the second section of the frame  48  and the third section  64  of the frame  48 . 
   Referring to  FIGS. 1 and 7 , during the assembly of a vehicle, typically an automobile, it is necessary to tighten a number of fasteners on a hub assembly  100 . This task is done at a dedicated jig  104  on an assembly line. In order to perform all of the necessary tightening operations, the position of the hub assembly  100  is rotated using a lifting device, such as a hoist (not shown). In order to secure the hub assembly  100  during the lifting operation and the tightening operations, the fixture  20  of the present invention is used. The fixture  20  allows for rotational movement of the hub assembly  100 , without extraneous movement such as swinging, or the need for the operator to support or steady the hub assembly  100 . 
   The first step in the operation is loading the hub assembly  100  as well as the fixture  20  onto the jig  104  on the assembly line. The hub assembly  100  is loaded in a manner well known to those skilled in the art. The base of the fixture  20  is also mounted to the jig  104  using four bolts that extend through openings  32 . The linearly movable housing  24  of the fixture  20  must be in a fully retracted position (see  FIG. 1 ) so there is no interference between the fixture  20  and the hub assembly  100  when the hub assembly  100  is attached to the jig  104  while the fixture  20  is already in place. 
   After the hub assembly  100  and fixture  20  are in place, the operator confirms that the support block  22  on the fixture  20  is in the proper position for the type of hub assembly being assembled. If the support block  22  is not in the proper portion, it must be rotated. Referring to  FIG. 6 , to rotate the support block  22 , the operator first removes the locking pin  30  that passes through the frame  48  of the housing  24  and into the locking bore  118  of the post  110  of the support block  22 . After the locking pin  30  is removed, the support block  22  is lifted slightly and is free to be rotated. The support block  22  is rotated so that the first bore  114  in the support block  22  is aligned with the stud  102  on the hub assembly  100  and the second bore  116  is moved out of alignment (or vise-versa depending on the original starting position). The locking pin  30  is then replaced to retain the support block  22  in the desired orientation. 
   Referring to  FIGS. 5 and 7 , the support block  22  must next be moved into position to secure the hub assembly  100 . The support block  22  is fixed to the housing  24  and the housing  24  can be slid along the base  26  of the fixture  20 . The operator grasps the handle  28  and pushes the housing  24  along the base  26  until the stud  102  on the hub assembly  100  passes through the associated bore  114  or  116  of the support block  22 . Because the housing  24  includes a flange  40  protruding out of the bottom that rides within the channel  42  defined by the base  26 , there is no way that the housing  24  will jump out of alignment with the hub assembly  100 . The handle  28  is pushed downward into the channel  36 . The notch  94  abuts the end of the channel  36  and prevents movement of the housing when the handle is pushed down and the housing in an engaged position. Once the support block  22  is in place, the operator can begin the operation of tightening fasteners on the hub assembly  100 . When the hub assembly  100  must be rotated to access some of the fasteners, a lifting device is simply attached to the hub assembly  100  opposite the stud  102  that is engaged with the fixture. As the hub assembly  100  is lifted, it rotates, preferably ninety degrees. The hub assembly rotates  100  around the stud  102  and fixture  20  which remain stationary. 
   After all necessary fastener tightening steps have been taken, the hub assembly  100  is lowered back into the initial position. Referring to  FIG. 3 , the hub assembly  100  is released from the fixture  20  when the operator again grasps the handle  28 , lifts the handle out of its locked position, and pulls the housing  24  from one end of the base  26  to the opposite end. Movement of the housing  24  stops when the flange  40  reaches the end of the channel  42  in the base  26 . Once the hub assembly stud  102  has been removed from the support block  22 , the hub assembly  100  may be removed from the jig  104  and advanced to the next stage of the assembly line. 
   The process is then repeated with a new hub assembly  100 . If the hub assembly  100  is of the same type just removed, no adjustments to the fixture  20  need to be made. Once the hub assembly is placed in the jig  104 , there is proper alignment between the support block  22  of the fixture and the stud  102  on the hub assembly  100 , and the support block  22  and stud  102  may be slidingly engaged. If a hub assembly  100  of a different type is placed in the jig  104 , only rotation of the support block  22 , as described above, is required to provide proper alignment. No additional realignment of the fixture  20  or the hub assembly  100  is required. As a result, many hub assemblies  100  may be efficiently worked on in an assembly line process due to the quick, precise and repeatable manner in which individual hub assemblies  100  are secured in place by the fixture  20  of the present invention. 
   Instead of providing a housing that comprises a slider and a frame, the housing may be fabricated in a single piece. The locking pin may be threaded and the bores on the post of the support block provided with matching threads or alternatively other locking functions for the locking pin may be used such as including a spring loaded ball bearing at the end of the locking pin and a receptor within the bore on the support block. 
   Although the invention has been shown and described with reference to certain preferred and alternate embodiments, the invention is not limited to these specific embodiments. Minor variations and insubstantial differences in the various combinations of materials and methods of application may occur to those of ordinary skill in the art while remaining within the scope of the invention as claimed and equivalents.