You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
BACKGROUND OF THE INVENTION 
   The present invention relates generally to tractors and front loaders, and more particularly to a bracket for attaching a front loader to a tractor. 
   It is common practice for tractors to include loaders to which a large variety of attachments can be connected to provide a wide range of applications in the agricultural, industrial and construction fields. Such loaders are usually mounted on the front end of a tractor and generally include a bracket, acting as the interface between the tractor and the loader, a loader frame assembly, boom arms pivotally mounted to the frame, an attachment mounted across the forward ends of the boom arms, tilt cylinders coupled between the attachment and the boom arms, and a lift cylinder or cylinders coupled between the frame assembly and the boom arms. An exemplary structure of this general type loader/tractor/bracket is shown in U.S. Pat. No. 5,895,199 to Baumert, III et al. 
   The normal commercial practice for providing a tractor with a loader to an end customer is to build the tractor and ship it to a local dealer where the bracket and loader are then affixed to the tractor prior to delivery. Alternatively, in the case of a later decision, this process may occur in the field after purchase and use of the tractor by the customer. The problems associated with dealer installation of the loader are significant in the practical world. For instance, dealer installation in most cases requires extensive removal of tractor components to complete, and thus takes considerable time. Time is money. Additionally, dealer installation requires clamping/friction loads on the joint between the front and rear pieces. It is preferable that the loading on the bolts be in tension and compression. Dealer installation also requires periodic hardware torque checks to maintain integrity. 
   It would be of significant advantage to develop a simple, yet reliable mounting bracket that reduces or eliminates the above-described problems and difficulties. 
   SUMMARY OF THE INVENTION 
   Accordingly, it is an important object of the present invention is to provide a method to reduce the complexity, time required and cost of adding a loader to a tractor after its manufacture. 
   It is another object of the present invention to provide a method to simplify the process of adding a loader to a tractor after or at the time of sale of the tractor to an end customer. 
   It is another object of the present invention to provide a two-piece loader bracket for greatly reducing the complexity, labor and cost of adding a loader to a tractor after the tractor has been manufactured. 
   It is another object of the present invention to provide a two-piece bracket for mounting a loader to a tractor, each piece having a generally vertical planar surface with bolt holes therethrough in matching patterns to permit a rigid connection between the pieces. 
   It is a still further object of the present invention to provide a loader bracket comprised of a front piece and a rear piece. The rear piece is rigidly affixed to the tractor during the manufacturing process and the front piece is selectively added later when it is determined to incorporate a loader. 
   It is another object of the present invention to provide a two-piece bracket for mounting a loader to a tractor, each piece having a generally vertical planar surface with bolt holes therethrough in matching patterns to permit a rigid connection between the pieces. 
   It is another object of the present invention to provide a mounting bracket for a loader that is durable in construction, inexpensive to manufacture, carefree of maintenance, facile in assemblage, and simple, versatile and effective in use. 
   These and other objects are achieved by providing method and apparatus to simplify the process of adding a loader to a tractor after the manufacturing process. A pair of mounting brackets, one on each side of the tractor, each comprise a front piece and a rear piece. The rear piece is affixed to the tractor during the manufacturing process and the front piece, including a bearing surface for a transverse support axis of a loader, is selectively affixed to the respective rear piece and tractor when a decision to incorporate a loader is taken. 

   
     DESCRIPTION OF THE DRAWINGS 
     The advantages of this invention will be apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
       FIG. 1  is a partial left side elevational view of a tractor with a break-away showing the mounting bracket of the instant invention with a cut-out portion showing the construction of the front piece; 
       FIG. 2  is a perspective exploded view of a right side bracket of the instant invention; 
       FIG. 3  is a front plan view of the front piece of  FIG. 2 ; and 
       FIG. 4  is a top plan view of the front piece of  FIG. 2 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Many of the fastening, connection, processes and other means and components utilized in this invention are widely known and used in the field of the invention described, and their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art, and they will not therefore be discussed in significant detail. Also, any reference herein to the terms “left” or “right” are used as a matter of mere convenience, and are determined by standing at the rear of the machine facing in its normal direction of travel. Furthermore, the various components shown or described herein for any specific application of this invention can be varied or altered as anticipated by this invention and the practice of a specific application of any element may already by widely known or used in the art by persons skilled in the art and each will likewise not therefore be discussed in significant detail. 
     FIG. 1  shows an exemplary tractor to which the instant invention may be incorporated. Generally, tractor  10  has a longitudinal axis (not shown) extending through the tractor in a direction corresponding to a line defined generally by the direction of movement of the tractor. A generally longitudinal main frame  11  supported by wheel pairs  12 ,  14  may be incorporated as a primary structural element of tractor  10  and to which many of the tractor components are attached. Alternatively, the rear axle and transmission assembly could fill the need for structural strength, and as the support for other tractor components, such as an engine  16  and cab  18 . Of course, one of skill in the art will understand that other structural arrangements are possible and in use. 
   For purposes of clarity, it should be appreciated that the bracket of the instant invention will be described and shown as a left-hand bracket. In most cases, two brackets will be required, one on each side of the tractor, to support an axis for the loader. The left and right-hand brackets, particularly the front pieces thereof, while similar are in reality mirror images of each other. 
   Referring still to  FIG. 1 , mounting bracket  20  comprises a rear piece  22  and a front piece  24 . Front piece  24  has a generally vertical member  26  with a semi-circular upward-opening bearing surface  28  holding a bushing  29  (best seen in  FIG. 2 ). Exemplary loader  30  has a plurality of linkages (most not numbered) terminating forwardly with bucket  32  and rearwardly with attachment assembly  31 . Attachment assembly  31  may be a single structure or two interconnected structures, one adjacent each side of the tractor  10 . From each side of attachment assembly  31  a transverse axis or pin  34  extends outwardly to engage respective bearing surfaces  28 . Thus, the axle or pins  34  support the rear of loader  30 . Attachment assembly  31  is also bolted to front piece  22 , as at stop block  58 . 
     FIG. 2  provides a perspective representation of the rear and front pieces  22 ,  24 . Rear piece  22  includes a generally vertical planar surface  40 , generally perpendicular to the longitudinal axis of tractor  10 , with a plurality of bolt holes  42  therethrough; holes  42  arranged in a symmetrical pattern of two rows of two holes each. Other patterns could be used without straying from the concepts of the instant invention. Rear piece  22  further includes a rearwardly extending flange  44 , also with bolt holes therethrough; flange  44  being generally perpendicular to surface  40 . The bolt holes through flange  44  are arranged in a second pattern that matches a pattern of holes on a structural member of tractor  10 , such as, for example, the transmission or rear axle housing (neither shown) to rigidly affix rear piece  22  by bolts  46  to the tractor. In practice, rear piece  22  may be the same for the left and right sides or they may be slightly different depending upon other tractor components that may interfere with the attachment of the rear piece to a structural member of the tractor. 
   Referring to  FIGS. 2–4 , front piece  24  is comprised primarily of generally vertical member  26  and generally forwardly extending member  50  rigidly connect by gusset plates  52 ,  54  and  56  welded into an assembly. Depending upon the design of the loader, other elements may be associated with front piece  24 . Forwardly extending member  50  may be formed to fit the specific tractor to which it is to be attached. For example, as best seen in  FIGS. 2 and 4  a sloping step-like bend  60  is formed in member  50  to properly interface with a particular tractor structure while maintaining the vertical member  26  in proper alignment with the pivot pins on axis  34 . Bolts  62  affix the front piece to a structural member of tractor  10 . 
   A generally vertical planar surface  64  on gusset plate  56 , best seen in  FIG. 4 , has a plurality of bolt holes  66  therethrough arranged in the same pattern as the bolt holes through surface  40 . A similar pattern of bolts holes extend through gusset plate  54  such that bolts  68  extend through both gusset plates and the holes through surface  40  of rear piece  22  to draw surfaces  40 ,  64  together, forming a rigid connection between rear and front pieces  22 ,  24 . 
   Mounting bracket  20  provides considerable flexibility and efficiency in the commercial arena. A tractor may be assembled at the factory with the relatively inexpensive rear piece  22  in position, and then shipped to a dealer for sale. If a customer decides to purchase the tractor with a loader, or later decides to add a loader, the dealer&#39;s installation efforts and costs are significantly reduced because the installation of the front piece and loader requires much less effort than the installation of the full bracket and loader. Tractors are complex assemblies of thousands of parts and components, with many on, over or adjacent the area where the rear pieced is located. With the rear piece attached during assembly of the tractor, there is no need to remove or loosen most of those parts and components during installation of the front piece and loader. 
   It will be understood that changes in the details, materials, steps and arrangements of parts which have been described and illustrated to explain the nature of the invention will occur to and may be made by those skilled in the art upon a reading of this disclosure within the principles and scope of the invention. The foregoing description illustrates the preferred embodiment of the invention; however, concepts, as based upon the description, may be employed in other embodiments without departing from the scope of the inventions. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown.

Summary:
Method and apparatus to simplify the process of adding a loader to a tractor after the manufacturing process. A pair of mounting brackets, one on each side of the tractor, each comprises a front piece and a rear piece. The rear piece is affixed to the tractor during the manufacturing process and the front piece, including a bearing surface for a transverse support axis of a loader, is selectively affixed to the respective rear piece and tractor when a decision to incorporate a loader is taken.