CROSS-REFERENCE TO RELATED APPLICATION 
   This application is related to provisional patent application Ser. No. 60/446,220, filed Feb. 10, 2003. 


   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a system for mounting an accessory, such as a grass trimmer, to a riding lawnmower. 
   2. Discussion of the Related Art 
   In the field of lawn maintenance, a number of accessories may be needed in addition to a lawn mower to properly manicure a property. To prevent the mower operator from having to make multiple trips around the lawn after having mowed it, a variety of ways of combining lawn mowers with other accessories have been suggested. However, the prior art shows that attempts to mount accessories such as grass trimmers, edgers, and so forth to the mower have been insufficient in some respects. For the most part, where simple accessory mounting systems are suggested, the accessory is relatively rigidly mounted to the mower so that the mower operator is required to position the mower in order to position the accessory. Where the accessory is mounted in such a way as to grant a wider range of movement, the accessory mounting system often is mechanically complex and therefore susceptible to damage and expensive repairs. What is needed is an accessory mounting system that is simple, durable, and relatively inexpensive to manufacture and maintain, but that also provides the mower operator with a wide range of accessory positioning options that are relatively independent of the mower position. 
   SUMMARY OF THE INVENTION 
   A system for mounting a lawn care accessory to a lawnmower, tractor, or the like is disclosed. The accessory mounting system comprises at least one link between a vertical pivot member, forming an axis for horizontal movement of the accessory, and a horizontal pivot point allowing vertical movement of the accessory. 


   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Preferred exemplary embodiments of the invention are illustrated in the accompanying drawings, in which like reference numerals represent like parts throughout, and in which: 
       FIG. 1  is a perspective view of an embodiment of the present invention showing a vehicle such as a lawn tractor or mower with the accessory mounting system in a raised, retracted position; 
       FIG. 2  is identical to  FIG. 1  except that the accessory mounting system is shown in a lowered, extended position; 
       FIG. 3  is a top view of an embodiment of the present invention showing the accessory mounting system in an extended position adjacent the rear of an object, such as a tree, as the lawn tractor or mower approaches the object during forward movement; 
       FIG. 4  is a top view of an embodiment of the present invention showing the accessory mounting system in an extended position adjacent the side of the object; 
       FIG. 5  is a top view similar to  FIGS. 3 and 4  except showing the accessory mounting system in an extended position adjacent the front of the object; 
       FIG. 6  is a top view similar to  FIGS. 4 and 5 , but showing the accessory mounting system in the raised, retracted position after trimming around the object as in  FIGS. 3-5 ; 
       FIG. 7  is a perspective view of another embodiment of the present invention in which the accessory mounting system is located on the side of the lawnmower; 
       FIG. 8  is a side view of the embodiment shown in  FIG. 7 ; 
       FIG. 9  is a front view of the embodiment shown in  FIG. 7 ; and 
       FIG. 10  is a top view of the embodiment shown in  FIG. 7 . 
   


   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   As can be seen in  FIGS. 1 and 2 , in a first embodiment of the invention, an accessory  14  is attached to a lawnmower  10  through a mounting system that includes a linkage  12 . Linkage  12  enables movement of accessory  14  in both vertical and horizontal directions. In the illustrated embodiment, lawnmower  10  is a conventional riding lawnmower, and accessory  14  is a line trimmer. However, accessory  14  could be any conventional lawn care tool that may be mounted to lawnmower  10 . Further, lawnmower  10  need not be a riding mower, but could be replaced with a push-type lawnmower or a tractor. 
   Still looking at  FIGS. 1 and 2 , trimmer accessory  14  has a shaft  16  that supports the trimmer head  18 , which includes a trimmer line  20  in a known manner. A handle  22  is mounted at its lower end to a horizontal upper portion of shaft  16  so that handle  22  extends vertically upward from shaft  16 . Handle  22  includes a handgrip  24  at its upper end, and further includes an on/off switch for controlling operation of trimmer accessory  14 . The shaft  16  is supported by a brace  26 , and both shaft  16  and brace  26  are connected to a vertical pivot bar  28 . 
   The mounting system of the invention is in the form of a linkage  12  including an upper link member  30  and a lower link member  32 . The upper link member  30  has an upper outer bracket  34  mounted to its outer end. The upper outer bracket  34  is generally U-shaped, and a pivot plate  36  is located between the spaced apart legs of upper outer bracket  34 . Pivot plate  36  is pivotably mounted to upper outer bracket  34  by a pivot pin  38  that extends between the legs of upper outer bracket  34  and through an aligned opening formed in pivot plate  36 . In a similar manner, the lower link member  32  has a lower outer bracket  40  mounted to its outer end. The lower outer bracket  40  is constructed similarly to upper outer bracket  34 , and a pivot plate  42  is pivotably mounted to lower outer bracket  40  by a pivot pin  44 . The vertical pivot bar  28  extends between the upper pivot plate  36  and the lower pivot plate  42 , and is pivotable about a generally vertical pivot axis. Representatively, pivot bar  28  may be in the form of a vertical bar that extends between upper pivot plate  36  and lower pivot plate  42 , together with a cylindrical sleeve defining a passage through which the vertical bar extends, such that the cylindrical sleeve is pivotable about a vertical pivot axis defined by the vertical bar. Brace  26  and the inner end of shaft  16  are mounted to the cylindrical sleeve, to enable horizontal movement of the handle  22 , shaft  16  and trimmer head  18 . 
   To provide the trimmer head  18  with movement in the vertical direction, upper link member  30  is connected to an upper inner bracket  46 , which contains an upper clevis  48  secured by a pivot pin  50 . In a similar manner, the lower link member  32  is connected to a lower inner bracket  52 , which contains a lower clevis  54  secured by a pivot pin  56 . 
   The linkage  12  may be mounted to a lawnmower  10  by attaching upper clevis  48  and lower clevis  54  respectively to upper  58  and lower  60  rear hitch members of lawnmower  10  in a known manner. Upper clevis  48  and lower clevis  54  are mounted to upper and lower hitch receivers, respectively, of lawnmower  10  via vertically aligned pivot pins. This allows for additional horizontal movement of the trimmer head  18 , in that a first vertical axis of rotation for trimmer head  14  relative to linkage  12  is defined by pivot bar  28 , and a second vertical axis of rotation for linkage  12  is defined by the aligned hitch receiver mounting pins. This provides articulated movement in a horizontal direction, which significantly increases the range and flexibility of movement of trimmer  14 . 
   Referring now to  FIGS. 7-10 , a second embodiment is shown in which the linkage  12  is mounted to lawnmower  10  at another location. Although a variety of ways of mounting the linkage  12  to another location are possible, the illustrated embodiment shows a pair of bars having clevis ends  48 ,  54  extending from the right side of the body of mower  10 . These could be integrally formed or attached in any suitable fashion and could be connected with any side of mower  10 . 
   A biasing member  62  is attached between the upper link member  30  and the lower clevis  54 . Biasing member  62  is present in each of the embodiments, but is best seen in  FIGS. 7 and 8 . Biasing member  62  functions to counterbalance the weight of the outer linkage and trimmer components, to bias the trimmer  14  to a raised, inoperative position, and to enable a user to easily lower the trimmer  14  against the biasing force provided by biasing member  62 . In the illustrated embodiments, biasing member  62  is a gas spring cylinder although it is understood that any other suitable biasing arrangement may be employed. 
   Referring now to  FIG. 3 , in use and operation, trimmer  14  is retracted while the mower operator cuts grass with mower  10 . When the operator approaches a tree T or other object, he or she grasps handgrip  24  of handle  22  to move trimmer head  18  of trimmer  14  near to tree T. The operator exerts a downward force, which allows handle  22 , shaft  16 , brace  26 , and trimmer head  18  to pivot downwards from the upper  48  and lower  54  clevis and into an operative position. 
   Trimmer head  18  can be laterally maneuvered close to tree T through a force applied to handle  22  by the operator in a horizontal direction. Upon application of an outward force in this manner, handle  22 , shaft  16 , brace  26 , and trimmer head  18  pivot horizontally on vertical pivot bar  28 . Linkage  12  pivots on the aligned hitch mounting pivot pins to provide a second vertical pivot axis for trimmer head  18 , which increases the range of movement of trimmer head  18 . The construction of linkage  12  functions to maintain trimmer head  18  parallel to the ground during use. In addition, the central mounting of linkage  12  relative to lawnmower  10  enables trimmer head  18  to be moved to the opposite side of lawnmower  10 , which enables a user to trim about objects on either side of lawnmower  10  during use. When the task has been completed, the user releases the downward force on the handgrip  24 , and biasing member  62  returns the trimmer  14  and linkage  12  to a raised, inoperative position. The user then returns trimmer  14  and linkage  12  to the retracted position as shown in  FIG. 6 . 
   Shaft  16  is configured to provide an open area between brace  26  and the vertical portion of shaft  16  to which trimmer head  18  is connected, to enable trimmer head  18  to be maneuvered about objects during operation. 
   Pivot bar  28  may include a torsion spring or the like for biasing trimmer  14  inwardly to a retracted position toward lawnmower  10 . Likewise, the vertically aligned hitch mounting pins may also include a torsion spring arrangement or the like, for biasing linkage  12  forwardly to a retracted position toward lawnmower  10 . In each case, a detent may be provided for releasably maintaining the trimmer  14  and linkage  12  toward the retracted position. 
   During operation, the articulated construction of the mounting system of the present invention prevents trimmer  14  and the mounting system from being damaged in the event trimmer  14  or trimmer head  18  strikes an object during movement of lawnmower  10 . The pivotable mounting of linkage  12  to lawnmower  10  and the pivotable mounting of trimmer  14  to linkage  12  allows the unit to fold up or swing out of the path of the object when an object is encountered during movement and operation. 
   It is contemplated that trimmer  14  may be powered from the battery or any other satisfactory connection to the electrical system of lawnmower  10 . It is also contemplated that trimmer  14  may be powered by a gasoline engine or in any other satisfactory manner. Trimmer head  18  may have an automatic line feed or a manual line feed in which line is advanced using a bump-type motion, in a manner as is known. In addition, while trimmer  14  is shown as a line-type trimmer, it is also understood that trimmer  14  may also be of the type that utilizes blades or other means for trimming. 
   While trimmer  14  is shown and described as being manually operated, it is also contemplated that pneumatic or hydraulic cylinders may be interconnected with linkage  12  and trimmer  14 , which would be operable to control the position of trimmer head  18  via a controller such as a joystick or the like. 
   It is further contemplated that various other types of lawn care accessories or equipment may be mounted to lawnmower  10  using the linkage arrangement of the present invention. In addition, it is understood that the mounting system of the present invention may be used to mount any type of accessory to any type of moving vehicle, and is not limited to use in combination with a riding lawnmower. Further, it is understood that various other arrangements may be employed for linking a lawn care accessory to a riding lawnmower to allow for vertical and horizontal movement of the accessory by varying the position of the handgrip. 
   Various alternatives and modifications are contemplated as being within the scope of the following claims particularly pointing out and distinctly claiming the subject matter regarded as the invention.
The present invention is related to lawn maintenance and describes a system for mounting an accessory, such as a grass trimmer, to a riding lawnmower. The mounting system is simple, durable, and relatively inexpensive to manufacture and maintain, but provides a lawnmower operator the ability to operate an accessory while seated in the lawnmower. The mounting system is also advantageous in that the lawnmower operator need not specifically align the mower with any objects that present an obstacle for mowing, but may instead move the accessory to the object. The accessory mounting system comprises at least one link between a vertical pivot bar forming an axis for horizontal movement of the accessory and horizontal pivot point allowing vertical movement of the accessory.