Abstract:
A coupling assembly for a machine includes a work implement having a float mode, in which the work implement moves relative to the machine, and a lock mode, in which the work implement has a fixed position relative to the machine. A pin assembly connects the work implement to the machine and itself is movable between a float position, in which the pin assembly supports the work implement in the float mode, and a lock position, in which the pin assembly supports the work implement in a lock mode. A retainer has a float assembly configuration, in which the retainer holds the pin assembly in the float position, and a lock assembly configuration, in which the retainer holds the pin assembly in the lock position, thereby facilitating adjustment of the work implement between float and lock modes.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure generally relates to coupling assemblies, and more particularly to pin assemblies used in coupling assemblies to connect work implements to machines. 
       BACKGROUND 
       [0002]    Auxiliary components, such as work implements, are often attached to machines using coupling assemblies. For example, a reversible blade (which may be used for clearing snow) may be attached to the front of a motor grader using a coupling assembly. More specifically, the reversible blade may include a connecting bracket and the motor grader may have a frame that supports a mounting bracket. The connecting bracket and mounting bracket may be attached by a pin that extends through apertures formed in the brackets. 
         [0003]    In some applications, it may be desirable for the coupling assembly to selectively support the work implement in either “float” or “locked” (also known as “no-float”) configurations. When in the float configuration, the work implement is permitted a limited amount of movement, such as rotation or translation, relative to the machine. Conversely, in the locked or no-float configuration, the work implement is secured in a substantially fixed position relative to the machine. Under certain working conditions, such as when the machine traverses uneven terrain, it may be advantageous to permit the work implement to float, thereby to interact more closely with the terrain. Other working conditions, however, may dictate that the work implement be locked or otherwise restrained from floating. 
         [0004]    Current coupling assemblies are overly difficult and cumbersome to switch between the float and locked configurations. For example, some coupling assemblies have separate float and lock brackets on the work implement. The float bracket may have a slot sized to slidably receive the pin, while the lock bracket may have an aperture sized to closely fit the pin. Substantial disassembly and reassembly is needed to switch between float and lock configurations. If the conventional coupling assembly is in the lock configuration but the float configuration is desired, the coupling assembly must be at least partially disassembled to remove the pin from the lock bracket. Next, the lock bracket must be detached from the work implement and the float bracket must be attached to the work implement. The coupling assembly must then be reassembled so that the pin is now inserted through the float bracket. In some applications, such as implements used on earth moving machines, the work implement and coupling assembly may be extremely large and heavy. This not only increases the time, effort, and cost associated with disassembling the coupling assembly, swapping brackets, and reassembling the coupling assembly, but also discourages the operator from switching between float and lock configurations even when it would be advantageous to do so. 
       SUMMARY OF THE DISCLOSURE 
       [0005]    In accordance with one aspect of the disclosure, a coupling assembly is provided for a machine. The coupling assembly includes a work implement having a float mode, in which the work implement moves relative to the machine, and a lock mode, in which the work implement has a fixed position relative to the machine. The coupling assembly also includes a pin assembly connecting the work implement to the machine, the pin assembly being movable between a float position, in which the pin assembly supports the work implement in the float mode, and a lock position, in which the pin assembly supports the work implement in a lock mode. A retainer is provided having a float assembly configuration, in which the retainer holds the pin assembly in the float position, and a lock assembly configuration, in which the retainer holds the pin assembly in the lock position. 
         [0006]    In another aspect of the disclosure that may be combined with any of these aspects, a coupling assembly is provided for a machine having a mounting bracket. The coupling assembly includes a work implement having a work implement bracket with an interior wall defining a slot positioned at a coupling point. A pin assembly includes a pin extending along a pin axis and sized for insertion through the mounting bracket and the slot, a float cam coupled to the pin and having a float cam exterior surface defining a float profile, the float profile of the float cam exterior surface being configured relative to the work implement bracket interior wall to permit movement of the float cam relative to the slot, and a lock plate coupled to the pin and having a lock plate exterior surface defining a lock profile, the lock profile of the lock plate exterior surface being configured relative to the work implement bracket interior wall to secure the lock plate in a substantially fixed position relative to the work implement bracket. A retainer has a float assembly configuration, in which the retainer holds the pin in a float position so that the float cam is positioned at the coupling point, and a lock assembly configuration, in which the retainer holds the pin in a lock position so that the lock plate is positioned at the coupling point. 
         [0007]    In another aspect of the disclosure that may be combined with any of these aspects, a pin assembly is provided for coupling a first bracket to a second bracket, the second bracket having a second bracket interior wall defining a slot positioned at a coupling point. The pin assembly includes a pin extending along a pin axis and sized for insertion through the first bracket and the slot, a float cam coupled to the pin and having a float cam exterior surface defining a float profile, the float profile of the float cam exterior surface being configured relative to the second bracket interior wall to permit movement of the float cam relative to the slot, and a lock plate coupled to the pin and having a lock plate exterior surface defining a lock profile, the lock profile of the lock plate exterior surface being configured relative to the second bracket interior wall to secure the lock plate in a substantially fixed position relative to the second bracket. A retainer has a float assembly configuration, in which the retainer holds the pin in a float position so that the float cam is positioned at the coupling point, and a lock assembly configuration, in which the retainer holds the pin in a lock position so that the lock plate is positioned at the coupling point. 
         [0008]    In another aspect of the disclosure that may be combined with any of these aspects, the retainer in the float assembly configuration has a first orientation relative to the pin assembly, the retainer in the lock assembly configuration has a second orientation relative to the pin assembly, and the first orientation is inverted relative to the second orientation. 
         [0009]    In another aspect of the disclosure that may be combined with any of these aspects, the float cam is coupled to the pin at a float cam connection point, the lock plate is coupled to the pin at a lock plate connection point, the lock plate connection point being spaced from float cam connection point by an axial length along the pin axis, and the retainer includes a retainer plate having a first end configured to mechanically engage the pin, and a spacer defining an effective spacer length substantially equal to the axial length between the float cam connection point and lock plate connection point, wherein the spacer is disposed between the retainer plate and the machine in one of the float and lock assembly configurations, and the spacer is not disposed between the retainer plate and the machine in a remaining one of the float and lock assembly configurations. 
         [0010]    In another aspect of the disclosure that may be combined with any of these aspects, the spacer is coupled to the retainer plate. 
         [0011]    In another aspect of the disclosure that may be combined with any of these aspects, the pin defines a channel sized to receive the retainer plate first end in both the first and second orientations of the retainer. 
         [0012]    In another aspect of the disclosure that may be combined with any of these aspects, the lock profile of the lock plate exterior surface has a lock profile shape complementary to a shape of the work implement bracket interior wall. 
         [0013]    In another aspect of the disclosure that may be combined with any of these aspects, the float cam comprises a bearing having an inner race and an outer race rotatable relative to the inner race and defining the float cam exterior surface. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a side elevation view of a work implement, in the form of a reversible blade, coupled to a machine, in the form of a motor grader, by a coupling assembly constructed according to the present disclosure. 
           [0015]      FIG. 2  is an enlarged plan view of  FIG. 1  showing the coupling assembly joining the work implement to the machine. 
           [0016]      FIG. 3  is a perspective view of the coupling assembly in a float configuration. 
           [0017]      FIG. 4  is a perspective view of the coupling assembly in a lock configuration. 
           [0018]      FIG. 5  is a perspective view of a pin assembly used in the coupling assembly. 
           [0019]      FIG. 6  is an exploded perspective view of the pin assembly of  FIG. 5 . 
           [0020]      FIG. 7  is a plan view of a float cam of the coupling assembly disposed in a slot of a work implement bracket. 
           [0021]      FIG. 8  is a plan view of a lock plate of the coupling assembly disposed in a slot of a work implement bracket. 
           [0022]      FIGS. 9A to 9D  are plan views of alternative embodiments of lock plates having different lock profiles. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    Referring now to the drawings, and with specific reference to  FIGS. 1 and 2 , a work implement  10  is shown mounted on a frame  12  of a machine  2  by a coupling assembly  14  having a float configuration and a lock configuration. As understood more fully below, the coupling assembly  14  may be switched quickly and easily to support the work implement  10  in either float mode or lock mode. In “float mode,” the coupling assembly  14  permits the work implement  10  to translate and/or rotate relative to the machine  2  along at least one axis, typically a lateral axis. By contrast, in “lock mode” the coupling assembly  14  secures the work implement  10  in a substantially fixed position relative to the machine  2 . 
         [0024]    The exemplary machine  2  is illustrated as a motor grader having a chassis  3  from which forwardly extends the frame  12 . A forward end of the frame  12  may include an A-frame  11  and may be supported by ground engaging units, such as a pair of wheels  5 . Similarly, the chassis  3  may be supported by ground engaging units, such as two pairs of wheels  5 . The chassis  3  supports an engine  6  and an operator cab  7 . A work blade  8  depends downwardly from the frame  12  and may be selectively operated to engage the ground  9 . 
         [0025]    While the exemplary embodiment of the machine  2  is described herein as a motor grader, the teachings of this disclosure can be employed on other earth moving or construction machines including, but not limited to, wheel loaders, back-hoes, lift-trucks, cherry-pickers, forklifts, excavators, tractors, track-type tractors, trucks, or any other movable vehicle. Similarly, while the work implement  10  is described herein as a reversible blade, the teachings of this disclose can be employed on other types of work implements such as straight blades, universal blades, blade rakes, v-plows, scarifiers, buckets, or other implements that may benefit from being able to selectively float relative to the machine to which it is coupled. 
         [0026]    As best shown in  FIGS. 2-4 , a machine bracket  20  is coupled to the A-frame  11  and includes spaced first and second plates  22 ,  24 . The first plate  22  defines a first aperture  26  and the second plate  24  defines a second aperture  28  aligned with the first aperture  26 . Referring to  FIG. 2 , the machine  2  may include hydraulic actuators  30 ,  32  extending between the A-frame  11  and the work implement  10 . 
         [0027]    In the illustrated embodiment, the work implement  10  is shown as a reversible blade having a moldboard  34  coupled to an implement frame  36 . A work implement bracket  38  is coupled to the implement frame  36  and includes a base  40  and a lug  42 . The lug  42  is sized for insertion between the first and second plates  22 ,  24  of the machine bracket  20 . Additionally, the lug  42  includes an interior wall  44  defining a slot  46 . While the slot  46  is illustrated as having an obround shape, the slot  46  may be provided in other shapes without departing from the present disclosure. The work implement bracket  38  may be positioned so that the slot  46  is aligned with the first and second apertures  26 ,  28  to define a coupling point for the coupling assembly  14 , as will be better understood below. Because the slot  46  is formed in the lug  42 , the coupling point is also located between the first and second plates  22 ,  24  of the machine bracket  20 . 
         [0028]    The coupling assembly  14  further includes a pin assembly  50  for mechanically coupling the machine bracket  20  to the work implement bracket  38 . With reference to  FIGS. 3-5 , the pin assembly  50  includes a pin  52  extending along a pin axis  54  and sized for insertion through the first and second apertures  26 ,  28  as well as the slot  46 . As best shown in  FIG. 6 , the pin  52  includes a first end  56  formed with a channel  58  and a second end  60  that is tapered to facilitate insertion of the pin  52  through a float cam  62  and snap ring  80  (discussed in greater detail below) located between the first and second apertures  26 ,  28  and the slot  46 . The pin  52  further may include a through hole  59  and a seat  61 . 
         [0029]    The pin assembly  50  further includes a float cam  62  coupled to the pin  52  that is used when the coupling assembly  14  is in the float configuration. The float cam  62  has a float cam exterior surface  64  configured to permit movement of the work implement bracket  38  relative to the pin  52 . More specifically, the float cam exterior surface  64  defines a float profile  66  that is configured relative to the interior wall  44  of the work implement bracket  38  to permit movement of the float cam  62  within the slot  46 . For example, as best shown in  FIG. 7 , the float profile  66  of the float cam exterior surface  64  may have a circular shape while the interior wall  44  of the work implement bracket  38  has an obround shape. As a result, the float cam  62  is permitted limited movement within the slot relative to the work implement bracket  38 , such as translation in the direction of arrows  68 ,  70  and/or rotation about a reference axis  72  as indicated by arrow  74 . While a circular float profile  66  and an obround-shaped interior wall  44  are shown, it will be appreciated that other shapes may be used for the float profile  66  and interior wall  44  as long as they permit movement of the float cam  62  relative to the work implement bracket  38  in at least one degree of freedom. 
         [0030]    In the illustrated embodiment, the float cam  62  is provided as a bearing having an inner race  76  and an outer race  78  rotatable relative to the inner race  76 , as best shown in  FIG. 6 . A snap ring  80  sized to engage the seat  61  may be used to secure the float cam  62  in the desired position on the pin  52 . In some embodiments, the inner race  76  is formed of plastic while the outer race  78  is formed of steel, however other materials may be used without departing from the scope of the present disclosure. Still further, while providing the float cam  62  in the form of a bearing may facilitate movement of the work implement bracket  38  relative to the pin  52 , in some applications the float cam  62  does not rotate. 
         [0031]    When in the “float configuration,” the coupling assembly  14  permits the work implement  10  to move with respect to the frame  12  of the machine  2  relative to at least one axis. In the exemplary embodiments, the pin assembly  50  enables the work implement  10  to rotate, or “oscillate” about a lower connection point, which in the case of the reversible blade depicted in  FIGS. 1 and 2  is a ball and socket connection. The pin assembly  50  thus allows the work implement  10  to rotate from side-to-side relative to a horizontal axis running along the fore-aft direction of the machine  2 , similar to the direction of “roll” in an aircraft. In this exemplary embodiment, therefore, the pin assembly  50  provides freedom of rotation of the work implement  10 , although translation may be construed by the linear travel of the float cam  62  within the slot  46 . Further, it is possible to provide two pin assemblies  50  at different positions and in different orientations, one of the pin assemblies may be configured to permit rotational float while the other of the pin assemblies may be configured to permit translational float. 
         [0032]    The coupling assembly  14  also includes a lock plate  82  coupled to the pin  52  that is used when the coupling assembly  14  is in the lock configuration. The lock plate  82  has a lock plate exterior surface  84  configured to prevent movement of the work implement bracket  38  relative to the pin  52 . More specifically, the lock plate exterior surface  84  defines a lock profile  86  that is configured relative to the interior wall  44  of the work implement bracket  38  to prevent movement of the lock plate  82  within the slot  46 , thereby to secure the pin  52  in a substantially fixed position relative to the work implement bracket  38 . In some applications, the lock profile  86  of the lock plate exterior surface  84  has a lock profile shape that is complementary to a shape of the interior wall  44  of the work implement bracket, as shown in  FIG. 8  where both the lock profile shape and interior wall shape are obround. It is not necessary for the lock profile shape and the interior wall shape to be complementary, however, as long as the shape of the lock profile  86  prevents movement of the lock plate  82  within the slot  46 . Some examples of the lock profile  86  and interior wall  44  having non-complementary shapes are illustrated at  FIGS. 9A-9D . 
         [0033]    The lock plate  82  may be secured to the pin  52  by a retaining pin  88 . More specifically, a through hole  90  extends through the lock plate  82  and the lock plate  82  may be positioned along the pin  52  so that the lock plate through hole  90  is aligned with the pin through hole  59 . The retaining pin  88  then may be inserted through both through holes  59 ,  90  to secure the lock plate  82  in the desired position. 
         [0034]    The coupling assembly  14  also includes a retainer  100  for holding the pin  52  in a desired position relative to the machine bracket  20  and the work implement bracket  38 . In the illustrated embodiment, the retainer  100  includes a retainer plate  102 , a spacer  104 , and a fastener  106 . The retainer plate  102  includes a connection end  108  formed with an arcuate recess  110  having a shape that may be complementary to the channel  58 . The channel  58  is sized to receive a thickness of the retainer connection end  108 . The retainer plate  102  also includes an aperture for receiving the fastener  106 , which may extend into and threadably engage the first plate  22  of the machine bracket  20 . The spacer  104  may be provided as an annular collar having an interior hole through which the fastener  106  may pass. In the illustrated embodiment, the spacer  104  is attached to the retainer plate  102 , however the spacer  104  may alternatively be provided as a separate component. 
         [0035]    The spacer  104  may be sized to facilitate switching the coupling assembly  14  between float and lock configurations. As best shown in  FIGS. 5 and 6 , the float cam  62  is coupled to the pin  52  at a float connection point  111 , while the lock plate  82  is coupled to the pin  52  at a lock connection point  112 . The lock connection point  112  is spaced from float connection point  111  by an axial length “L” ( FIG. 6 ) along the pin axis  54 . The spacer  104  may have an effective spacer length “S” that is substantially equal to the axial length “L”. 
       INDUSTRIAL APPLICABILITY 
       [0036]    From the foregoing, it can be seen that the technology disclosed herein has industrial applicability in a variety of settings such as, but not limited to, providing a coupling assembly between a machine and a work implement having both float and lock configurations. As will be understood from the above, switching the coupling assembly between float and lock configurations requires only that the pin  52  be adjusted to the desired position, thereby greatly simplifying this operation. Furthermore, when the spacer  104  is sized as described above and attached to the retainer plate  102 , the operator need only flip over the retainer plate  102  to switch the elevation of the retainer plate  102 . 
         [0037]    More specifically, the retainer  100  may be placed in a first assembly configuration, in which the spacer  104  is disposed between the first plate  22  of the machine bracket  20  and the retainer plate  102 , thereby to position the retainer plate  102  at a first elevation relative to the first plate  22 . In the illustrated embodiment, when the retainer plate is at the first elevation, the retainer plate  102  will secure the pin  52  in a float position, in which the float cam  62  is positioned at the coupling point, as best shown in  FIG. 3 . With the pin  52  in the float position, the float cam  62  allows the work implement bracket  38  to move relative to the pin  52 , thereby allowing the work implement  10  to float relative to the frame  12  of the machine  2 . 
         [0038]    Alternatively, the retainer  100  may be placed in a second assembly configuration, in which the spacer is not disposed between the first plate  22  of the machine bracket  20  and the retainer plate  102 , thereby to position the retainer plate at a second elevation relative to the first plate  22 . In the illustrated embodiment, when the retainer plate  102  is positioned at the second elevation, the retainer plate will secure the pin  52  in a lock position, in which the lock plate  82  is positioned at the coupling point, as best shown in  FIG. 4 . With the pin  52  in the lock position, the lock plate  82  prevents relative movement between the pin  52  and work implement bracket  38 , thereby to fix a position of the work implement  10  relative to the frame  12  of the machine  2  and prevent float. 
         [0039]    When the spacer  104  is attached to the retainer plate  102 , the retainer  100  may be quickly and easily switched between the first and second assembly configurations. More specifically, the retainer  100  may be placed in the first assembly configuration by placing the retainer plate in a first orientation, in which the spacer  104  faces toward the first plate  22  of the machine bracket  20 . Additionally, the retainer  100  may be placed in the second assembly configuration by placing the retainer plate in a second orientation, in which the spacer  104  faces away from the first plate  22  of the machine bracket  20 . In this embodiment, switching the retainer  100  between first and second orientations (and, therefore, switching the coupling assembly between float and lock configurations) requires the operator to simply remove the fastener  106 , flip over the retainer plate  102  from the first to the second orientation (or vice versa), and reattach the fastener  106 . 
         [0040]    All references to the disclosure or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation as to the scope of the disclosure more generally. All language of distinction and disparagement with respect to certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the disclosure entirely unless otherwise indicated. Moreover, all methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context.