Patent Publication Number: US-2022232765-A1

Title: Grass mower

Description:
INCORPORATION BY REFERENCE 
     The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2021-009808 filed on Jan. 25, 2021. The content of the application is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to a grass mower. 
     Description of the Related Art 
     Heretofore, there has been disclosed a technology of adjusting a mowing height by raising and lowering a mowing blade relative to a mower body in a grass mower, particularly an autonomous grass mower (e.g., see Japanese Patent Laid-Open No. 2017-112927). 
     In this technology, the grass mower body does not have any change in relative position of height with respect to the ground, and a mowing blade unit only changes in position in an up-down direction. 
     According to a technology of raising and lowering a mowing blade itself in Japanese Patent Laid-Open No. 2017-112927 mentioned above, however, there is a restriction on a size of a traveling machine body, and thus a change width of a mowing height varies according to the restriction. 
     In general, multiple types of grass mowers having sizes corresponding to sizes of respective yards are manufactured and sold, but the change width of the mowing height varies with the size of the traveling machine body. 
     Also, it is general that the mowing height is 60 mm at maximum in Europe, and 100 mm at maximum in America, and there is regionality in lawn mowing height. Therefore, it is necessary to remake a frame case in accordance with the regionality in mowing height, and thus it is necessary to invest in respective molding molds. 
     Consequently, an object of the present invention, which has been made in view of the above respects, is to provide a grass mower that can achieve various mowing heights by changing mounting positions of a traveling machine body and a working machine body. 
     SUMMARY OF THE INVENTION 
     To achieve the above object, an aspect of the present invention provides a grass mower including a traveling machine body including a driving source and a driving part driven by the driving source; and a working machine body including a mowing blade, the working machine body being coupled to the traveling machine body, wherein one of the traveling machine body and the working machine body includes a support member including an upper member and a lower member, and the other machine body includes an insertion support member being insertable between the upper member and the lower member, the grass mower including a coupling member that is couplable selectively in a first state where the insertion support member is inserted between the upper member and the lower member, and a second state where the insertion support member is mounted on an upper surface of the upper member or a lower surface of the lower member. 
     In the above configuration, each of the upper member, the lower member and the insertion support member is provided with a coupling hole, and the coupling member is passed through the coupling hole to couple the upper member and the lower member to the insertion support member. 
     In the above configuration, the traveling machine body and the working machine body are coupled with a first coupling member that couples the traveling machine body with the working machine body in the front and a second coupling member that couples the traveling machine body with the working machine body in the rear. 
     In the above configuration, one of the insertion support member being coupled with the first coupling member and the insertion support member being coupled with the second coupling member is disposed in a front end of the traveling machine body or the working machine body, and the other insertion support member is disposed laterally with respect to a front-rear direction. 
     The above configuration includes a gap member that surrounds a gap between the upper member and the lower member in the coupling member, during coupling in the second state. 
     In the above configuration, the gap member is an elastic body. 
     The above configuration includes a metal collar disposed between the coupling member and the gap member. 
     The above configuration includes two side frames each including the driving part, a rear frame including the driving source, and a front frame including the mowing blade and a mowing blade driving source that drives the mowing blade. 
     In the above configuration, the side frame and the front frame are coupled with the coupling member. 
     Advantageous Effect of Invention 
     According to an aspect of the present invention, a grass mowing work can be performed at two mowing heights by selecting a first state or a second state, and coupling and fixing a support member and an insertion support member. Therefore, mowing height adjustment can be performed in a comparatively large range with one type of frame configuration, and multiple frame configurations do not have to be prepared for the mowing height adjustment, and additionally, manufacturing cost can be reduced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a plan view showing a structure of a grass mower according to the present invention; 
         FIG. 2  is a perspective view showing a first state of the grass mower seen from front; 
         FIG. 3  is a perspective view showing the first state of the grass mower seen from rear; 
         FIG. 4  is a perspective view of a front support member part in the first state; 
         FIG. 5  is a cross-sectional view of the front support member part in the first state; 
         FIG. 6  is a perspective view of a rear support member part in the first state; 
         FIG. 7  is a cross-sectional view of the rear support member part in the first state; 
         FIG. 8  is a perspective view showing a second state of the grass mower seen from front; 
         FIG. 9  is a perspective view showing the second state of the grass mower seen from rear; 
         FIG. 10  is a perspective view of the front support member part in the second state; 
         FIG. 11  is a cross-sectional view of the front support member part in the second state; 
         FIG. 12  is a perspective view of the rear support member part in the second state; and 
         FIG. 13  is a cross-sectional view of the rear support member part in the second state. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Hereinafter, description will be made as to an embodiment of the present invention with reference to the drawings. 
       FIG. 1  is a plan view showing a structure of a grass mower.  FIG. 2  is a perspective view showing a first state of the grass mower seen from front.  FIG. 3  is a perspective view showing the first state of the grass mower seen from rear.  FIG. 4  is a perspective view of a front support member part in the first state.  FIG. 5  is a cross-sectional view of the front support member part in the first state.  FIG. 6  is a perspective view of a rear support member part in the first state.  FIG. 7  is a cross-sectional view of the rear support member part in the first state.  FIG. 8  is a perspective view showing a second state of the grass mower seen from front.  FIG. 9  is a perspective view showing the second state of the grass mower seen from rear.  FIG. 10  is a perspective view of the front support member part in the second state.  FIG. 11  is a cross-sectional view of the front support member part in the second state.  FIG. 12  is a perspective view of the rear support member part in the second state.  FIG. 13  is a cross-sectional view of the rear support member part in the second state. 
     As shown in  FIG. 1 , a grass mower  1  is an autonomous traveling grass mower  1  that can autonomously travel without being operated by an operator. 
     The grass mower  1  includes a traveling machine body  12  including a traveling motor  10  as a driving source and driving wheels  11  as driving parts each driven by the traveling motor  10 , and a working machine body  13  including a mowing blade (not shown in the drawing), the working machine body being coupled to the traveling machine body  12 . 
     The traveling machine body  12  includes a rear frame  20 , and a pair of side frames  21  provided on right and left of the rear frame  20 . 
     The traveling motor  10  is disposed in the rear frame  20 , and each driving wheel  11  is rotatably driven, and supported in each side frame  21 . The respective driving wheels  11  can be individually driven by the traveling motor  10 , and the grass mower  1  is driven to travel and driven to roll, by individually driving the driving wheels  11 . 
     In a front end of each side frame  21 , a steering wheel  14  steerable to right and left is provided. 
     In front of the pair of side frames  21 , a front frame  22  is provided. In the front frame  22 , the working machine body  13  is disposed. 
     The working machine body  13  includes a mowing blade motor as a mowing blade driving source, and a mowing blade disk that is a circular disk provided with the mowing blade (each part is not shown in the drawing), and lawn can be mowed by driving and rotating the mowing blade disk with the mowing blade motor. 
     In addition, a cover that covers all of the front frame  22 , the rear frame  20  and the side frames  21  is mounted above the frames, and the cover is not shown in the drawing. 
     In the present embodiment, as shown in  FIGS. 2, 3, 11 and 12 , front support members  30  are provided in front corners of the front frame  22 . Each front support member  30  includes a front upper member  31  and a front lower member  32  that are disposed with a predetermined gap in an up-down direction. 
     In each of the front upper member  31  and the front lower member  32 , a coupling hole  33  is formed. 
     In the front end of each side frame  21 , a front insertion support member  34  is provided that can be inserted between the front upper member  31  and the front lower member  32  in the front support member  30 . 
     The front insertion support member  34  is formed in a cylindrical shape extending in the up-down direction, and a cylindrical portion of the front insertion support member  34  forms a coupling hole. 
     Inside the front insertion support member  34 , a cylindrical collar  35  made of a metal material can be inserted. 
     Furthermore, the front insertion support member  34  is formed with a height dimension slightly smaller than a gap dimension between the upper member and the lower member in the front support member  30 , and the front insertion support member  34  can be inserted between the upper member and the lower member. 
     Then, a bolt  36  as a first coupling member is inserted into the coupling hole  33  and the cylindrical portion (coupling hole) of the front insertion support member  34 , and the bolt  36  is tightened with a nut  37 , in a state where the front insertion support member  34  is inserted between the front upper member  31  and the front lower member  32 , to couple and fix the front upper member  31  and the front lower member  32  to the front insertion support member  34 . 
     This state is referred to as the first state where lawn can be mowed to be low. 
     Also, as shown in  FIGS. 8 to 11 , each front insertion support member  34  is disposed on a lower surface side of the front lower member  32 , and the bolt  36  is inserted into the coupling hole  33  and the cylindrical portion of the front insertion support member  34 , and is tightened with the nut  37 , so that the grass mower can be supported in the second state where lawn can be mowed to be high. 
     In the second state, a gap member  38  is provided to cover an outer peripheral side of each bolt  36  between the front upper member  31  and the front lower member  32 . The gap member  38  is formed of, for example, an elastic body of resin, rubber or the like. 
     The first state and the second state indicate that the front frame  22  is supported in states different from each other in height approximately by only the height dimension of the front insertion support member  34 . 
     Also, as shown in  FIGS. 6, 7, 12 and 13 , a rear support member  40  is provided in each rear corner of the front frame  22 . The rear support member  40  is formed in a concave shape recessed inwardly from a side surface of the front frame  22 , and the rear support member  40  includes a rear upper member  41  and a rear lower member  42 . 
     At a position corresponding to the rear support member  40  that is a middle portion of each side frame  21 , a rear insertion support member  43  being formed in a convex shape entering a recess portion of the rear support member  40  is provided. The rear insertion support member  43  is disposed laterally (inwardly) with respect to a front-rear direction of the side frame  21 . 
     Then, a bolt  44  as a second coupling member is inserted into each coupling hole  33  and a cylindrical portion (coupling hole) of the rear insertion support member  43 , and the bolt  44  is tightened with a nut  45 , in a state where the rear insertion support member  43  is inserted between the rear upper member  41  and the rear lower member  42 , to couple and fix the rear upper member  41  and the rear lower member  42  to the rear insertion support member  43 . This state is referred to as the first state. 
     Also, as shown in  FIGS. 8 to 13 , each rear insertion support member  43  is disposed on a lower surface side of the rear lower member  42 , and the bolt  44  is inserted into the coupling hole  33  and the cylindrical portion of the rear insertion support member  43 , and the bolt  44  is tightened with the nut  45 , so that the grass mower can be supported in the second state where lawn can be mowed to be high. 
     In the second state, the gap member  38  made of an elastic material that covers an outer peripheral side of each bolt  44  between the rear upper member  41  and the rear lower member  42  is provided. 
     Next, description will be made as to an operation of the present embodiment. 
     In the present embodiment, each bolt  36  as the coupling member is inserted into the coupling hole  33  and the cylindrical portion of the front insertion support member  34 , and the bolt  36  is tightened with the nut  37 , in the state where the front insertion support member  34  is inserted between the front upper member  31  and the front lower member  32 , to couple and fix the front upper member  31  and the front lower member  32  to the front insertion support member  34 . 
     At the same time, each bolt  44  as the coupling member is inserted into the coupling hole  33  and the cylindrical portion of the rear insertion support member  43 , and the bolt  44  is tightened with the nut  45 , in the state where the rear insertion support member  43  is inserted between the rear upper member  41  and the rear lower member  42 , to couple and fix the rear upper member  41  and the rear lower member  42  to the rear insertion support member  43 . 
     Consequently, the working machine body  13  supported in the front frame  22  can be held in the first state. 
     In this first state, for example, lawn can be mowed at a mowing height of 20 to 60 mm. 
     In this case, each side frame  21  is temporarily fixed with the front support member  30  and the front insertion support member  34 , the bolt  36  and the nut  37  at a front end portion of the side frame, and afterward, the side frame  21  is rotated along a side part of the rear frame  20 , to temporarily fix the rear support member  40  and the side frame  21 . Finally, the front support member  30 , the rear support member  40  and the side frame  21  are finally tightened, which facilitates assembling. 
     Also, each front insertion support member  34  is disposed on the lower surface side of the front lower member  32 , and the bolt  36  is inserted into the coupling hole  33  and the cylindrical portion of the front insertion support member  34 , and he bolt  36  is tightened with the nut  37 , to couple and fix the front insertion support member  34  to the lower surface side of the front lower member  32 . 
     At the same time, each rear insertion support member  43  is disposed on the lower surface side of the rear lower member  42 , and the bolt  44  is inserted into the coupling hole  33  and the cylindrical portion of the rear insertion support member  43 , and the bolt  44  is tightened with the nut  45 , to couple and fix the rear insertion support member  43  to the lower surface side of the rear lower member  42 . 
     Consequently, the working machine body  13  supported in the front frame  22  can be held in the second state. 
     In this second state, for example, lawn can be mowed at a mowing height of 60 to 100 mm. 
     As described above, in the present embodiment, the grass mower includes the traveling machine body  12  including the traveling motor  10  (driving source) and the driving wheels  11  (driving part) driven by the traveling motor  10 , and the working machine body  13  including the mowing blade, the working machine body  13  being coupled to the traveling machine body  12 . The front frame  22  that supports the working machine body  13  includes the front support member  30  and the rear support member  40 , and each side frame  21  that supports the traveling machine body  12  includes the front insertion support member  34  and the rear insertion support member  43  that can be inserted into the front support member  30  and the rear support member  40 , respectively. The grass mower includes the bolts  36  and  44  (first and second coupling members) that are couplable selectively in the first state where the front insertion support member  34  and the rear insertion support member  43  are inserted between the front upper member  31  and the rear upper member  41 , and the front lower member  32  and the rear lower member  42 , and the second state where the front insertion support member  34  and the rear insertion support member  43  are mounted on lower surfaces of the front lower member  32  and the rear lower member  42 , respectively. 
     Consequently, a mowing work can be performed at two mowing heights by selecting the first state or the second state, and coupling and fixing the front support member  30  and the rear support member  40  to the front insertion support member  34  and the rear insertion support member  43 , respectively. Therefore, mowing height adjustment can be performed in a comparatively large range with one type of frame configuration, and multiple frame configurations do not have to be prepared for the mowing height adjustment, and additionally, manufacturing cost can be reduced. 
     Also, in the present embodiment, the front upper member  31  and the rear upper member  41 , the front lower member  32  and the rear lower member  42 , and the front insertion support member  34  and the rear insertion support member  43  are provided with the coupling holes  33 , respectively, and the bolts  36  and  44  (first and second coupling members) are passed through the coupling holes  33  to couple the front upper member  31  and the rear upper member  41 , and the front lower member  32  and the rear lower member  42 , to the front insertion support member  34  and the rear insertion support member  43 . 
     Consequently, the front support member  30  and the rear support member  40 , and the front insertion support member  34  and the rear insertion support member  43  can be coupled and fixed only by inserting the bolts  36  and  44 . 
     In this case, each side frame  21  is temporarily fixed to the front support member  30  at a front end portion of the side frame  21 , and afterward the side frame  21  is rotated along the side part of the rear frame  20 , to temporarily fix the rear support member  40  and the side frame  21 . Then the front support member  30 , the rear support member  40  and the side frame  21  are finally tightened, so that the assembling can be performed easily. 
     Further, in the present embodiment, the front insertion support member  34  is disposed in the front end of the side frame  21 , and the rear insertion support member  43  is disposed laterally with respect to the front-rear direction of the side frame  21 . 
     Consequently, the front insertion support member  34  and the rear insertion support member  43  can firmly support the front frame  22  (working machine body) being coupled to the side frame  21  in the front and rear. 
     Also, the present embodiment includes the gap member  38  that surrounds a gap between the front upper member  31  or rear upper member  41  and the front lower member  32  or rear lower member  42  in the bolt  36  or  44  (coupling member), during coupling in the second state. 
     Consequently, a periphery of the bolt  36  or  44  can be covered. 
     Further, in the present embodiment, the gap member  38  is the elastic body. 
     Consequently, the periphery of the bolt  44  can be covered with the gap member  38  being composed of the elastic body. Further, since the gap member  38  is the elastic body, the gap member  38  contracts in the up-down direction during tightening of the bolt  44 , and the gap member can be attached further closely to the rear upper member  41  or the rear lower member  42 , and can be firmly fixed. 
     Also, the present embodiment includes the metal collar  35  disposed between the bolt  36  or  44  (coupling member) and the gap member  38 . 
     Consequently, the collar  35  eliminates gaps between the front insertion support member  34  and rear insertion support member  43 , and the bolts  36  and  44 , so that occurrence of rattling can be suppressed. 
     Note that the above embodiment is merely one aspect of the present invention, and can be arbitrarily modified and applied without departing from the scope of the gist of the present invention. 
     For example, in the above embodiment, the front insertion support member  34  and the rear insertion support member  43  are disposed on the lower surface sides of the front support member  30  and the rear support member  40 , respectively, to constitute the second state. Alternatively, the front insertion support member  34  and the rear insertion support member  43  may be disposed on upper surface sides of the front support member  30  and the rear support member  40 , respectively. In this case, this state may be considered the second state, or a third state. 
     Furthermore, the front support member  30  and the rear support member  40  may be provided in each side frame  21 , and the front insertion support member  34  and the rear insertion support member  43  may also be provided in the front frame  22 . 
     REFERENCE SIGNS LIST 
     
         
           1  grass mower 
           10  traveling motor 
           11  driving wheel 
           12  traveling machine body 
           13  working machine body 
           14  steering wheel 
           20  rear frame 
           21  side frame 
           22  front frame 
           30  front support member 
           31  front upper member 
           32  front lower member 
           33  coupling hole 
           34  front insertion support member 
           35  collar 
           36  bolt 
           37  nut 
           38  gap member 
           40  rear support member 
           41  rear upper member 
           42  rear lower member 
           43  rear insertion support member 
           44  bolt 
           45  nut