Abstract:
A coupling device for coupling a tool to a motor grader machine includes a main body assembly, a wedge assembly attached to the main body assembly, wherein the wedge assembly is configured to rigidly secure the tool to the main body assembly. A retainer assembly may be attached to the main body assembly, wherein the retainer assembly is configured to mount directly to a tool mount assembly of the motor grader machine.

Description:
TECHNICAL FIELD 
       [0001]    This disclosure relates generally to a quick coupling device, and more particularly to a coupling system for mounting specialized tools to a machine. 
       BACKGROUND 
       [0002]    Motor graders are typically used to perform displacement, distribution and leveling of material, such as soil. Generally, a motor grader includes a tractor unit coupled to a grader group via a tow bar assembly. The grader group may include a specialized tool, such as a blade assembly, having a grader blade, as well as a mounting assembly with retainers. The tool, for example, a blade assembly, may be positioned in the retainers such that the tool is supported by the mounting assembly. The tractor unit may move the tool, for example, the blade assembly, over the ground, so that the grader blade engages with the material, such as soil, so as to displace, distribute, or level the soil. 
         [0003]    Motor graders, while capable machines, may be regarded as somewhat specialized machines. Their service may only be required for limited, often seasonal, tasks such as gravel road maintenance or heavy snow removal. Some efforts have been made to increase the versatility of the aforementioned machines, such as by utilizing various specialized tools in operations performed by the motor grader. 
         [0004]    U.S. Pat. No. 5,419,104 issued to Higdon discloses a supporting frame for attaching a mower to a road grader or similar prime mover. A main mounting frame is provided for attachment to a pair of horizontal members and vertical supports located on the road grader. However, the attachment of Higdon is coupled directly to the road grader and does not provide convenient or easily exchangeable means for coupling other kinds of equipment, such as other specialized tools, to the road grader. In addition, the attachment of Higdon does not include readily available structure to provide varying degrees of motion such as vertical, horizontal, or rotational movement. Furthermore, the attachment of Higdon may not provide an appropriate degree of rigid connection between the attachment and the road grader for performing some operations requiring, for example, high precision or elevated levels of applied force. 
         [0005]    The present disclosure is directed towards overcoming one or more of the shortcomings set forth above. 
       SUMMARY OF THE INVENTION 
       [0006]    In accordance with one disclosed exemplary embodiment, a coupling device for coupling a tool to a motor grader machine may include a main body assembly, a wedge assembly attached to the main body assembly, wherein the wedge assembly is configured to rigidly secure the tool to the main body assembly. A retainer assembly may be attached to the main body assembly, wherein the retainer assembly is configured to mount directly to a tool mount assembly of the motor grader machine. 
         [0007]    According to another exemplary disclosed embodiment, a method is provided for coupling a tool to a motor grader machine. The method includes mounting a coupling device to a drawbar and circle assembly of the machine and mounting a tool to the coupling device. 
         [0008]    According to yet another disclosed embodiment, a machine for performing displacement, distribution or leveling of material may include a drawbar and circle assembly having a tool mount assembly, a coupling device connected to the tool mount assembly, and a tool rigidly connected to the coupling device. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]      FIG. 1  provides a diagrammatic side view of a motor grader according to an exemplary disclosed embodiment; 
           [0010]      FIG. 2  provides a diagrammatic perspective view of a drawbar and circle assembly of the motor grader of  FIG. 1  in connection with a coupling mechanism; 
           [0011]      FIG. 3  provides a diagrammatic rear view of the coupling mechanism of  FIG. 2 ; 
           [0012]      FIG. 4  provides a diagrammatic front view of the coupling mechanism of  FIG. 2 ; 
           [0013]      FIG. 5  provides a diagrammatic detail view of components of a wedge lock coupling assembly of the coupling mechanism of  FIGS. 3 and 4 ; 
           [0014]      FIG. 6  provides a diagrammatic view of a pin assembly of the wedge lock of  FIG. 5 ; 
           [0015]      FIG. 7  provides a diagrammatic detail view of internal components of the coupling mechanism of  FIGS. 3 and 4 ; 
           [0016]      FIG. 8  provides a diagrammatic view of a tool according to an exemplary disclosed embodiment; 
           [0017]      FIG. 9  provides a diagrammatic view of the tool of  FIG. 8  and coupling mechanism of  FIGS. 3 and 4 ; 
           [0018]      FIG. 10  provides a diagrammatic side view of the coupling mechanism and tool of the motor grader of  FIG. 2 . 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    Referring to the figures, a motor grader is shown generally at  10  in  FIG. 1 . The motor grader  10  may include a frame assembly  11  for supporting a drawbar-circle-moldboard (DCM)  16 . A moldboard or specialized tool  18  may be coupled to the DCM  16 . The motor grader  10  may be driven by an engine contained, for example, in an engine enclosure  14 . An operator cab  12  containing the controls necessary to operate the motor grader  10  may be mounted on the frame assembly  11 . 
         [0020]    Turning to  FIG. 2 , a drawbar  13  is shown in connection with a circle  15  to form a drawbar and circle assembly. The drawbar  13  may include an arrangement or steel tubes, for example, and other elements which attach to the circle  15 . The circle  15  may include a circular gear set which allows rotation of an item, such as a specialized tool  18 , connected thereto. A sideshift mount  22  may be attached to the circle  15 . The disclosed embodiment illustrates the coupler mechanism  20  mounted to the sideshift mount  22 . Hence, the coupler mechanism  20  may be connected to the circle  15  via the sideshift mount  22 . A sideshift cylinder  19  of sideshift mount  22  may also be attached to coupler mechanism  20 , such as by a mounting bracket  17 . A specialized tool  18 , for example, a moldboard, may be attached to coupler mechanism  20  as detailed below. 
         [0021]    A rear view of the coupler mechanism  20  is illustrated in  FIG. 3 . The coupler mechanism  20  may include a main body assembly  21 . The main body assembly  21  may include a back plate  23 , side plates  25 , top plate  27 , and bottom plate  29 .  FIG. 4 , illustrates a front view of the coupler mechanism  20 . The main body assembly  21  may also include front plate  31 . Components of the main body assembly  21  may be joined together, such as by welded assembly, to form an assembly which may encapsulate interior components as detailed below. The main body assembly  21  may further include a plurality of sideshift surfaces or rails  24 . One rail  24  may be mounted to the back plate  23  generally along a top edge thereof such as along a length of top plate  27 . Another rail  24  may be mounted to the back plate  23  generally along a bottom edge thereof such as along a length of bottom plate  29 . A configuration of back plate  23  may be formed to generally accommodate an exterior shape of sideshift mount  22  when assembled thereto. 
         [0022]    In one disclosed embodiment, a plurality of mounting plates may be secured to front plate  31 .  FIG. 4  depicts a first mounting plate  32  and second mounting plate  34  secured to front plate  31 . First mounting plate  32  and second mounting plate  34  may be coupled to front plate  31  using retaining members such as bolted assemblies inserted through apertures  60 . Fixed wedge surfaces  30  may be configured along a bottom portion of first mounting plate  32  and second mounting plate  34 . 
         [0023]      FIG. 5  illustrates an interior surface  58  of second mounting plate  34 . (A similar symmetrical setup may be provided for first mounting plate  32 .) Components of a wedge lock coupler assembly  35  are shown secured to interior surface  58 . A cam holder  52  having a lower wedge  50  configuration is shown secured to interior surface  58 . An over-center rest  48  may be attached to cam holder  52  by a retaining member  59 . A cam  54  may be disposed within a slot  55  of cam holder  52 . One end of cam  54  may be coupled to an end of a connecting rod  42  such as via a retaining member  61 . The other end of the connecting rod  42  may be attached to a plunger  66  of a pin  26 . Pin  26  may include an upper wedge  36  configuration in a surface thereof. Pin  26  may be retained by a pin holder  40 . Pin holder  40  may include a pickup surface  38 . 
         [0024]    Turning to  FIG. 6 , pin  26  may include a pin casing  62  having an interior  98  for receiving a spring  64 , for example, a Belleville spring stack. One end  100  of plunger  66  may also be received within the interior  98 . The end  100  of plunger  66  may be retained within the interior  98  via a snap ring  96  disposed within the interior  98 . The spring  64  may be retained between the end  100  of plunger  66  and an interior region  102  of pin casing  62 . 
         [0025]    The interior  98  may further include a recessed portion  90  for receiving an end of a restraint bar  92 . The end  100  of plunger  66  may also include a recessed portion  94  for receiving the other end of the restraint bar  92 . In some embodiments, an end of the restraint bar  92  may be attached within the recessed portion  94 . Restraint bar  92  may include a geometric shape, such as, for example, a square, cross, or hexagonal cross-configuration. Each one of the recessed portions  90  and  94  may also be configured to receive the cross-sectional configuration of the restraint bar  92  in mating relationship. Hence, an assembly of the aforementioned cross-sectional configurations of the restraint bar  92  disposed within recessed portions  90  and  94  may prevent the pin casing  62  from rotating or turning with respect to the plunger  66 . This may help ensure proper alignment of the pin  26 , such as the upper wedge  36  configuration, with respect to another contact surface. 
         [0026]    Hence, when the pin  26  is retained in place, for example, via a locking member urged against the upper wedge  36  of the pin  26 , the plunger  66  may be enabled to become biased against the spring stack  64 . The spring stack  64  will, in turn, become biased against the interior region  102  of pin casing  62  to create a force between the upper wedge  36  and the locking member. Another advantage provided by the restraint bar  92  may include preventing the spring  64  from being over-compressed as the end  100  of plunger  66  is urged towards the interior region  102  of pin casing  62 . This may prevent damage to the spring  64 . 
         [0027]    Turning again to  FIG. 5 , another portion of cam  54  may be coupled to hydraulic cylinder rod  43  of hydraulic cylinder  44 , such as by a retaining member  63 . Hydraulic cylinder  44  may be attached to a cylinder holder  46  via a retaining member  65 . Hydraulic cylinder  44  may include various hydraulic line receptacles  56  for receiving or sending hydraulic fluid in a hydraulic circuit to activate or deactivate pin  26 . 
         [0028]    In the disclosed embodiment, cylinder holder  46 , pin holder  40 , and cam holder  52  may all be secured to second mounting plate  34 , such as by a welded assembly. However, other appropriate securing configurations may be used to rigidly attached the aforementioned components to the interior surface  58  of mounting plate  34 . Retaining members  59 ,  61 ,  63  and  65 , of the disclosed embodiment, may include, for example, a dowel pin and snap ring assembly or any other appropriate securing element(s) for joining the components of wedge lock coupler assembly  35 . 
         [0029]      FIG. 7  illustrates additional components and structure interior to main body assembly  21 . A reinforcing plate  72  may be located on an interior surface  73  of bottom plate  29 . Reinforcing plate  72  may include steel material and be secured by welding to main body assembly  21 . In the disclosed embodiment, the length of reinforcing plate  72  may run just outside of each wedge lock coupler assembly  35 . Reinforcing plate  72  may provide additional structural integrity and support to the main body assembly  21 . The length of reinforcing plate  72  may also be adjusted in accordance with meeting various strength and/or weight requirements of main body assembly  21 . Reinforcing plate  72  may include cut-outs to clear components, such as cam holder  52 . A similar reinforcing plate (not shown) may be provided to run along an interior of top plate  27 . In one disclosed embodiment, this reinforcing plate may be configured to traverse the entire length of the top plate to provide additional structural integrity and to support main body assembly  21 . Again, the length may be adjusted in accordance to meeting various strength and/or weight requirements of main body assembly  21 . 
         [0030]    Additional components of main body assembly  21  may include internal ribs  67 . As shown in  FIG. 7 , internal ribs  67  may be spaced apart along an interior  75  of main body assembly  21 . In one embodiment, internal ribs  67  are assembled generally perpendicular to longitudinal lengths of top plate  27  and bottom plate  29 . The internal ribs  67  may include cut-out portions to accommodate clearances of additional components within the interior  75  of main body assembly  21 . The internal ribs  67  may include steel material and be secured to the main body assembly  21  by welded assembly. 
         [0031]    A hydraulic routing assembly  69  is shown in connection with hydraulic cylinders  44  of each wedge lock coupler assembly  35 . An external hydraulic connection  74  may be secured to a surface of the main body assembly  21 . A hydraulic circuit, for example, provided by the motor grader  10  may be attached to the external hydraulic connection  74  to supply and/or return hydraulic fluid via hydraulic lines  76 ,  78  to hydraulic manifold  70 . Hydraulic hoses  68  may be coupled between hydraulic line receptacles  56  and hydraulic manifold  70 . 
         [0032]    Engagement indicators  71  may be provided to indicate to an operator that pins  26  are engaged with specialized tool  18 . In one embodiment, one end of the engagement indicator  71  may be attached to one end of a lever  77 , such as by a threaded weld nut or other appropriate retaining member. The other end or indicating end  81  may be guided through an aperture, for example, located in the top plate  27 . The other end of lever  77  may be connected to plunger  66  ( FIGS. 5 and 6 ) of pin  26  via retaining member  61 . 
         [0033]      FIG. 8  illustrates an example of a specialized tool  18  that can be connected to coupler mechanism  20 . The illustrated specialized tool  18  is a blade having upper wedge surfaces  80  and lower wedge surfaces  84 . Contact surface  82  abuts front plate  31 , first mounting plate  32 , and second mounting plate  34  ( FIG. 4 ) when the specialized tool  18  is attached to coupler mechanism  20  as discussed below. The blade shown in  FIG. 8  is for illustrative purposes only. Other specialized tools having appropriately located upper wedge surfaces  80  and lower wedge surfaces  84  may be utilized, including, for example, cold planers, street sweepers, grass mowers, etc. 
         [0034]    Thus, as shown in  FIG. 9 , the specialized tool  18  may be readily attached to coupler mechanism  20 . Coupler mechanism  20  may be retained by sideshift mount  22 .  FIG. 10 , depicts rails  24  of coupler mechanism  20  retained within upper retaining assembly  86  and lower retaining assembly  88  of sideshift mount  22 . 
       INDUSTRIAL APPLICABILITY 
       [0035]    The disclosed coupler mechanism  20  may have applicability in any system, for example, requiring rigid mounting of specialized tools to a machine. In one embodiment, the machine may include a motor grader  10 . 
         [0036]    In operation, coupler mechanism  20  may be utilized in connection with a drawbar and circle assembly of motor grader  10 . The disclosed embodiment provides a coupler mechanism  20  having respective rails  24  which are insertable within upper retaining assembly  86  and lower retaining assembly  88  of sideshift mount  22  for a drawbar and circle assembly ( FIG. 10 ). Sideshift cylinder  19  of sideshift mount  22  may also be attached to coupler mechanism  20 , such as by mounting bracket  17  ( FIG. 2 ). Once connected to the sideshift mount  22 , coupler mechanism  20  may be further connected to one of a variety of specialized tools  18 . 
         [0037]    The sideshift cylinder  19  may provide horizontal movement to attached coupler mechanism  20  with respect to the drawbar and circle assembly. Any other movement (e.g., rotational, vertical, tilting) produced, for example, by the drawbar and circle assembly may be translated to coupler mechanism  20 . The same kind of movement may further be translated to any rigidly connected specialized tool  18  connected to coupler mechanism  20 . 
         [0038]    Coupler mechanism  20  utilizes a wedge-lock coupler assembly  35  by taking two surfaces (e.g., upper wedge  36  and lower wedge  50 ) and pushing them apart to contact corresponding respective surfaces (e.g., wedge surfaces  80 ,  84 ) of a specialized tool  18 , and locking the tool  18  against coupler mechanism  20  to form a rigidly locked assembly. The lower wedges  50  of coupler mechanism  20  may serve as stationary wedge members. Upper wedge  36  surfaces of pins  26  may be translated away from lower wedges  50 . 
         [0039]    In one disclosed embodiment, pickup surfaces  38  of coupler mechanism  20  may be located within upper wedge surfaces  80  of specialized tool  18 . The wedge-lock coupler assembly  35  may be enabled by a hydraulic routing assembly  69  connected, for example, to a hydraulic circuit of a machine (such as motor grader  10 ). When connected to the hydraulic routing assembly  69 , hydraulic cylinders  44  may be activated to push hydraulic cylinder rods  43  (connected to cams  54 ) towards cam holders  52  in order to push pins  26  to engage upper wedges  36  (of pins  26 ) with upper wedge surfaces  80  (of tool  18 ). The cams may be urged past a longitudinal center of pins  26  until they come into contact with over-center rests  48 . As upper wedges  36  are disposed within upper wedge surfaces  80 , a combination of gravity and the weight of tool  18  may facilitate lower wedges  50  of coupler mechanism  20  to become disposed within lower wedge surfaces  84  of tool  18 . When pins  26  are fully extended within upper wedge surfaces  80 , front plate  31 , first mounting plate  32 , and second mounting plate  34  of main body assembly  21  are urged tightly against contact surface  82  of tool  18 . Additionally, when pins  26  are fully extended within upper wedge surfaces  80 , upper wedges  36  and lower wedges  50  become fully engaged with upper wedge surfaces  80  and lower wedge surfaces  84 , respectively, to form a rigidly locked connection between tool  18  and coupler mechanism  20 . 
         [0040]    When pins  26  are fully extended in a locked position, cams  54  have moved past over-center of a longitudinal line extending through pins  26  to rest against over-center rests  48 . Consequently, a bottom portion of connecting rods  42  may be slightly urged towards over-center rests  48 . This disclosed embodiment may provide an additional safety feature since any forces translated down through pins  26  would bear against the over-center rests  48  (as opposed to hydraulic cylinders  44 ) to prevent disengagement of pins  26 . This safety feature may facilitate retention of specialized tool  18  to coupler mechanism  20  until the tool  18  is hydraulically released from contact such that the cams  54  are urged in a direction towards hydraulic cylinders  44  thereby disengaging pins  26 . 
         [0041]    Another advantage afforded by coupler mechanism  20  may include the capability to readily mount directly to stock equipment such as to the drawbar and circle assembly of a motor grader  10 . Another feature of coupler mechanism  20  may include the capability of directly receiving various specialized tools  18 . These tools may include one of a variety of specialized tools  18  including, for example, a blade, a street sweeper, a cold planer, or a grass mower. A further benefit of coupler mechanism  20  may include an increased capability to rigidly hold and secure the various specialized tools  18  in position once they are assembled to the main body assembly  21 . 
         [0042]    In one example, the spring load (generated by coupler mechanism  20 ), exerted to produce a clamping load to secure the specialized tool  18 , may generate 18-20 kilonewtons of force. (This level of clamping force may be produced, for example, by utilizing an appropriate spring load, such as one produced by a Belleville spring stack  64  within pin  26 .) The disclosed system may produce clamping loads having a high order of magnitude. Hence, coupler mechanism  20  may retain specialized tools  18  in a more rigidly locked connection. The specialized tools  18  retained by coupler mechanism  20  may also be less susceptible to counter-acting forces applied to the tool during operation. Such a rigid connection may allow a machine to perform earth moving tasks in a more precise or accurate manner. 
         [0043]    In addition, the coupler mechanism  20  may increase the functionality of a readily available machine by allowing it to become more versatile. For example, a variety of specialized tools  18  may be connected to a single type of machine. This may allow the same machine to perform a multitude of tasks. Increasing the versatility of a machine may increase its operational usage, since the machine would not be relegated to performing only a specific task. This may also allow the equipment to become more cost effective by gaining greater usage from the machine. 
         [0044]    It will be apparent to those skilled in the art that various modifications and variations can be made in the disclosed quick connect mechanism and methods without departing from the scope of the disclosure. Additionally, other embodiments of the quick connect mechanism and methods will be apparent to those skill in the art from consideration of the specification. It is intended that the specification and examples be considered as exemplary only, with a true scope of the disclosure being indicated by the following claims and their equivalents.