Patent Abstract:
A reversible wing plow including a hitch, a moldboard and a moldboard shifting mechanism. The hitch is coupleable to the rear of a prime mover. The moldboard is operably coupled to the hitch proximate an inboard end and rotatable about a first horizontal axis that extends outwardly from the hitch generally parallel to a direction of forward movement of the prime mover. The moldboard shifting mechanism includes first and second linear actuators, both of which are coupled to the hitch at one end and coupled to opposing sides of a rotation crank plate on the other end. The crank plate is further operably coupled to the moldboard, whereby the moldboard is rotatably shiftable to the driver or passenger side of the prime mover, or to a vertically oriented transport position.

Full Description:
CLAIM TO PRIORITY 
     This application claims the benefit of U.S. Provisional Application 61/606,294, entitled “Reversible Wing Plow and Methods of Rotation” filed Mar. 2, 2012, which is hereby incorporated by reference. 
     TECHNICAL FIELD 
     The present invention relates generally to snow moving equipment. More particularly, the present invention relates to a wing plow for connection to the rear of a vehicle, wherein the wing plow includes a reversible moldboard that is configurable into a variety of positions. 
     BACKGROUND OF THE INVENTION 
     In the snow removal industry it is common practice to use a plow mounted to the front of a snow removal vehicle. The plow mounted to the front of the vehicle may be raised or lowered in relation to the traveled surface. When the plow is in the lowered position it is driven along by the vehicle; thereby pushing snow to one side or the other, depending on the operators&#39; manipulation of the angle of the plow relative to the travel direction. 
     Side mounted wing plows to supplement the front plow are also well known to the snow removal industry. A side wing plow is generally used when extra width of the plowing swath is desired and the perceived risks involved in the employment of a side wing plow do not exceed the benefits. Typically the side wing is mounted to the side of a moving vehicle (tractor, truck, loader or grader). Side wing plows typically include a portion referred to as a side wing plow moldboard, which is a curved metal blade used for pushing snow. 
     With a typical side wing plow, an operator can manipulate the side wing plow moldboard up or down relative to the surface to be plowed, as well as angle the side wing plow moldboard relative to the direction of travel. When an operator configures the side wing plow to its plowing position, and the vehicle to which the side wing plow is attached is generally moving forward, snow is discharged down the length of, and past the end of the side wing plow moldboard, thereby creating a cleared path parallel to the direction of travel of the vehicle. Accordingly, by utilizing the side wing plow, the operator can increase the width of cleared snow (i.e., the swath width) beyond that which a front plow is capable of clearing alone. This extra swath width is beneficial because it increases the amount of cleared snow and pavement in a given pass, thereby increasing productivity and reducing the overall cost of the snow removal process. 
     U.S. Pat. No. 4,096,652, and entitled “Retractable Snowplow Wing and Mounting Therefor” discloses a side wing plow mounted to one side of a vehicle. However, side wing plows such as this are limited to use on only one side of the vehicle, thereby limiting the operator efficiency. To accommodate for special circumstances where a side wing plow mounted to the opposite side of the vehicle is needed, oftentimes there is a one vehicle with an opposite mounted wing plow within the fleet of plows. Furthermore, when this type of side wing is in a transport, or upright position, the side wing plow greatly increases the overall width of the vehicle, thereby increasing the risk of accident. 
     Another demonstration of prior art can be seen in U.S. Pat. No. 3,241,254, entitled “Snow Wing for Motor Graders”. This again shows a side wing plow mounted to the side of a vehicle. Neither of these inventions allow for the immediate change of discharge of snow from one side of the vehicle to the other. 
     In accordance with the prior art, to accomplish snow discharge on either side of the vehicle, one would currently need to mount a large and cumbersome plowing apparatus on the rear of a vehicle; such a device is taught in U.S. Pat. No. 3,908,289, entitled “Swing-Over Snow Wing”. This device, however, is extremely large and complex, and requires a great deal of thought and manipulation by the operator to function properly. This device further causes a significant decrease in operator visibility when the wing plow is in the transport position, thereby adding an unnecessary safety risk. 
     Another possible solution is taught in U.S. Pat. No. 7,367,407, entitled “Towed Snowplow and Method of Plowing.” This device however, requires the plow to be trailered, thereby greatly reducing maneuverability. Accordingly, this device is not meant for use within cities where frequent backing up, or travel in reverse, may be necessary. 
     Collectively the prior art devices add immense weight, expense and complication to the efforts of snow removal. Moreover, because of their complexity and bulk, they decrease the operators&#39; focus, comfort and, most importantly, public safety. 
     Accordingly, there is a need in the snow removal industry for a wing plow that has a moldboard that can easily be moved from one side of the vehicle to the other, thereby allowing an increased swath width on either side of the vehicle without significantly adding to the weight, expense and complication of snow removal. 
     Additionally, there is a need in the snow removal industry for a wing plow with a moldboard that can be transported while maximizing the visibility of the operator to improve safety. 
     SUMMARY OF THE INVENTION 
     The present invention provides embodiments of a reversible wing plow with a prime mover. The reversible wing plow is comprised of a hitch, a moldboard and a moldboard shifting mechanism. The hitch is coupleable to the prime mover at a rear of the prime mover. The moldboard has an inboard end and an outboard end. The moldboard is operably coupled to the hitch proximate the inboard end and rotatable about a first horizontal axis that extends outwardly from the hitch generally parallel to a direction of forward movement of the prime mover. 
     The mold board shifting mechanism includes a first linear actuator and a second linear actuator. The first linear actuator has a first fixed end coupled to the hitch and a second moving end. The second linear actuator has a second fixed end coupled to the hitch and a second movable end. The first movable end of the first linear actuator and the second movable end of the second linear actuator are coupled to a rotation crank plate on opposing sides of the rotation crank plate. The crank plate is further operably coupled to the moldboard proximate the inboard end of the moldboard via a rotation member whereby the moldboard is rotatably shiftable between a first position extending outwardly on a first side of the prime mover to a second position extending outwardly on a second side of the prior mover and to a vertically oriented transport position between the first position and the second position by coordinated extension and retraction of the first linear actuator and the second linear actuator. 
     The above summary of the invention is not intended to describe each illustrated embodiment or every implementation of the present invention. The figures and the detailed description that follow more particularly exemplify these embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be more completely understood in consideration of the following detailed description of various embodiments of the invention, in connection with the accompanying drawings, in which: 
         FIG. 1  depicts a side view of a prime mover with reversible wing plow deployed to the driver side plowing position mounted to the rear of the prime mover by means of a three point hitch in accordance with an example embodiment of the invention; 
         FIG. 2  depicts a rear view a prime mover with reversible wing plow deployed to the driver side plowing position in accordance with an example embodiment of the invention; 
         FIG. 3  depicts a rear view a prime mover with reversible wing plow deployed to the passenger side plowing position in accordance with an example embodiment of the invention; 
         FIG. 4  depicts a side view of a prime mover with reversible wing plow positioned substantially vertically in accordance with an example embodiment of the invention; 
         FIGS. 5A through 5C  depict close-up rear view of the horizontal rotation of the wing plow moldboard as it hydraulically rotates relative to the prime mover in accordance with an example embodiment of the invention; 
         FIG. 6  depicts an isometric view of the operable coupling of the inboard end of the moldboard to the crank plate via a rotation member in accordance with an example embodiment of the invention; 
         FIG. 7A  depicts an isometric view of reversible wing plow with the moldboard folded in transport mode in accordance with an example embodiment of the invention; 
         FIG. 7B  depicts a close up isometric view of the automatic safety locking mechanism in transport mode in accordance with an example embodiment of the invention; 
         FIG. 8  depicts an isometric view of a prime mover with reversible wing plow including the operator-manipulated joystick and smart controller in accordance with an example embodiment of the invention; and 
         FIG. 9  depicts a schematic of the hydraulic control system in accordance with an example embodiment of the invention. 
     
    
    
     While the invention is amenable to various modifications and alternative forms, specifics thereof have by shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. 
     DETAILED DESCRIPTION 
     Referring now to the drawings and illustrative embodiments depicted therein, a reversible wing plow  10  for use with a prime mover  12  generally includes a hitch assembly  14 , a moldboard assembly  16 , a moldboard rotation assembly  18 , and an electro hydraulic control system  20 . 
     As best seen in  FIGS. 7A and 8 , hitch assembly  14  includes an L-shaped hitch plate  22 , a vertical member  24 , a horizontal member  26 , and a rotational shaft  28 . In an example embodiment of the invention, L-shaped hitch plate  22  can be positioned between the rear of prime mover  12  and moldboard assembly  16 . L-shaped hitch plate  22  can be integrated with, or coupled to, vertical member  24  and horizontal member  26 . 
     Vertical member  24  has a front surface  30 , a back surface  32  and an inboard shaft support  34 . Front surface  30  includes at least one vehicle mount coupler  36  for removable connection to prime mover  12 . Prime mover  12  can be a tractor, grader, loader, truck, or other suitable piece of motorized equipment having ground engaging wheels or tracks. In an example embodiment of the invention, vehicle mount coupler  36  can be a three-point hitch. The vehicle mount coupler  36  can allow for vertical ground clearance adjustment of reversible wing plow  10  separate from prime mover  12 . Back surface  32  includes hydraulic ram supports  38  and  39 , turning cylinders  40  and  41  and locking pin receiver  42 . Hydraulic ram supports  38  and  39  provide connection points for coupling one end of turning cylinders  40  and  41  to vertical member  24 . Turning cylinders  40  and  41  include a first double acting hydraulic lift cylinder  40  and a second double acting hydraulic lift cylinder  41 . Vertical member  24  further includes locking pin receiver  42 . Inboard shaft support  34  provides a rotational coupling point to, and support for, the inboard end of rotational shaft  28 . 
     Horizontal member  26  includes outboard shaft support  44  and reinforcements  46 . Outboard shaft support  44  provides a rotational coupling point to, and support for, the outboard end of rotational shaft  28 . Reinforcements  46  provide ample structural support for maintaining rotational shaft  28  substantially fixed in position relative to L-shaped hitch plate  22 , particularly when subjected to external forces in operation. 
     Rotational shaft  28  is oriented substantially horizontal and substantially parallel to the direction of travel of prime mover  12 . Rotational shaft  28  is supported at by inboard shaft support  34  and outboard shaft support  44 . Rotational shaft  28  can be laterally secured in place relative to the L-shaped hitch plate  22 , for example by a large nut or other common retainer. 
     As best seen in  FIGS. 2 ,  4  and  7 A, moldboard assembly  16 , generally includes moldboard  48  and moldboard hinge knuckle  50 . In the depicted embodiment, moldboard  48  includes cutting edges  52  and  53 , bracing  54 , inboard portion  56 , outboard portion  58 , and folding linkage assembly  60 . 
     Cutting edges  52  and  53  include a first cutting edge  52  and a second cutting edge  53 . Cutting edges  52  and  53  are positioned opposite one another on the lateral edges of moldboard  48 . Cutting edges  52  and  53  can be coupled to moldboard  48  in a manner that allows ease in periodic replacement, for example with a series of bolts or other suitable fasteners. 
     In an example embodiment of the invention, bracing  54  provides ample structural support for substantially maintaining the shape of moldboard  48 , particularly when subjected to external forces in operation. Bracing can be coupled both horizontally and vertically along a surface of moldboard  48 . 
     Inboard portion  56  of moldboard  48  includes folding cylinder mount  64 , link arm mount  66 , angle cylinder mount  67 , and a portion of folding hinge  68 . Folding cylinder mount  64  provides a connection point for pivotably coupling one end of double acting folding cylinder  76  to inboard portion  56 . Link arm mount  66  provides a connection point for pivotably coupling one end of link arm  72  to inboard portion  56 . In an example embodiment of the invention, angle cylinder mount  67 , can be coupled to the side of moldboard opposite folding cylinder mount  64  and link arm mount  66 , as show in  FIG. 6 . Angle cylinder mount  67  provides a connection point for pivotably coupling one end of angle cylinder  88  to moldboard assembly  16 . 
     In the depicted embodiment, outboard portion  58  of moldboard  48  includes pushrod mount  70  and a portion of folding hinge  68 . Pushrod mount  70  provides a connection point for pivotably coupling one end of push rod  74  to outboard portion  58 . Corresponding portions of folding hinge  68  are respectively coupled to inboard portion  56  and outboard portion  58  of moldboard  48 . These portions can be joined, for example by a pin, thereby hingedly coupling inboard portion  56  to outboard portion  58 . 
     Inboard portion  56  and outboard portion  58  of moldboard  48  can have a curved shape, thereby forming a channel to accommodate the flow of snow along the length of moldboard  48  when plowing. 
     In an example embodiment, folding linkage assembly  60  includes link arm  72 , pushrod  74  and double acting folding cylinder  76 . In an example embodiment of the invention, pushrod  74 , is pivotably coupled to outboard portion  58  at one end, and pivotably coupled to an end of link arm  72  on its other end. Link arm  72  is pivotably coupled to an end of pushrod  74  at one end and pivotably coupled to inboard portion  56  on the other end. Folding cylinder  76  is a double acting cylinder and is pivotably coupled to inboard portion  56  at one end, and pivotably coupled to an intermediate location on link arm  72  at its  76  the other end. 
     Moldboard hinge knuckle  50  is coupled to the inboard portion  56  of moldboard  48 , proximate the end opposite folding hinge  68 . Moldboard hinge knuckle  50  can be joined, for example, by hinge pin  94  to rotation member knuckle  92 , thereby hingedly coupling moldboard assembly  16  to moldboard rotation assembly  18 . Hinge pin  94  can be secured in place by a nut or other common retainer. 
     As best seen in  FIGS. 5 ,  6 ,  7 B, and  8 , moldboard rotation assembly  18  includes box channel  80 , hinge plate  82 , rotation crank plate  84 , angle cylinder support plate  86 , angle cylinder  88 , and locking cylinder  90 . 
     Box channel  80  is supported by, and rotationally coupled to, rotation shaft  28 . Hinge plate  82  is coupled to the end of box channel  80  distal to hitch assembly  14 . Hinge plate  82  includes rotational member knuckle  92  and hinge pin  94 . 
     Rotation crank plate  84  is coupled to the end of box channel  80  opposite hinge plate  82 , proximate to hitch assembly  14 . As best seen in  FIGS. 5 , in an example embodiment of the invention, rotation crank plate  84  includes two similar plates  96 , a first cylinder pin  98  and a second cylinder pin  100 . The two similar plates  96  can have apertures appropriately sized to accommodate first and second cylinder pins  98  and  100 . First cylinder pin  98  pivotably couples the end of first turning cylinder  40  to two similar plates  96 . Second cylinder pin  100  pivotably couples the end of second lift cylinder  41  to two rotation crank plates  96 . 
     As best seen in  FIGS. 6 , angle cylinder support plate  86  is coupled to box channel  80 . Angle cylinder support plate  86  pivotably couples to one end of angle cylinder  88 . The opposite end of angle cylinder  88  pivotably couples to angle cylinder support  67  of the moldboard assembly  16 . 
     As best seen in  FIG. 7B , locking cylinder  90  includes locking pin  91 , and is coupled to, and can be positioned substantially parallel to, the length of box channel  80  such that locking pin  91  can selectively extend through an aperture in two similar plates  96  and into locking pin receiver  42  of hitch assembly  14 . 
     As best seen in  FIGS. 8 and 9 , according to an example embodiment, electro hydraulic control system  20  includes hydraulic controls  102  and electronic control  104 . 
     Hydraulic controls  102  generally include angle cylinder valve  108 , accumulator  109 , lock cylinder valve  110 , folding cylinder valve  112 , turning cylinder valves  114 , float valves  116 , pressure sensor  117 , directional control valve  118 , and vehicle auxiliary  119 . Hydraulic controls  102  receive hydraulic pressure from a vehicle auxiliary  119 . 
     Electronic control  104  includes controller  120 , joystick  122  and button  124 . Controller  120  is a computer device that senses various electrical inputs and executes preset programs based on the sensed various electrical inputs. Controller  120  is in communication with hydraulic controls  102 . Joystick  122  and button  124  can be manipulated by an operator to provide various electrical inputs to controller  120 . 
     In operation, moldboard assembly  16  can rotate about the rotational shaft  28  of hitch assembly  14  more than 180 degrees, allowing the change of plowing positions from one side of prime mover  12  to the other side of prime mover  12 . In an example embodiment of the invention, rotation of moldboard assembly  16  is caused by turning cylinders  40  and  41 . Other methods of rotation, such as chains, cable, gears and motor are also contemplated. 
     To rotate moldboard assembly  16  from the driver side plowing position (as shown in  FIG. 5A ) to the passenger side plowing position (as shown in  FIG. 5C ) the operator can manipulate joystick  122  towards the passenger side of prime mover  12  until rotation is complete. Manipulation of joystick  122  will activate controller  120 , which in this case, executes a preset program to activate the lift mode of hydraulic controls  102 . Upon activating the lift mode of hydraulic controls  102 , individual valves  114 ,  116  and  118  are activated and fluid pressure is directed to turning cylinders  40  and  41 , thereby retracting turning cylinders  40  and  41  until they reach their equalized point (as shown in  FIG. 5B ). Once this equalized point is reached, and no further hydraulic fluid can be displaced, a pressure spike occurs in hydraulic controls  102 . This pressure spike causes pressure sensor  117  to send a signal to controller  120 . This input from pressure sensor  117  causes controller  120  to execute a preset program to activate the drop mode of hydraulic controls  102 . Once the drop mode is activated controller  120  will take into consideration the direction in which the operator has manipulated joystick  122 . Based on a preset program, then controller  120  activates valves  114  to reverse the flow of hydraulic fluid to one of the turning cylinders  40  and  41 . The reversed turning cylinder  40  or  41  then extends, thereby overpowering the other turning cylinder  40  or  41  to continue rotation of moldboard assembly  16  in the direction that the operator has manipulated joystick  122 . 
     If the operator continues to hold joystick  122  in the same position after rotation of moldboard assembly  16  has subsided, controller  120  executes a preset program to activate the float mode of hydraulic controls  102 . The float mode removes retraction or extension pressure to turning cylinders  40  and  41  and allows free movement of hydraulic fluid through the turning cylinders  40  and  41 , thereby allowing gravity to keep cutting edge  52  or  53  of moldboard  48  against the plowing surface, particularly in uneven terrain. Float mode is activated by deactivating individual valves  114  and  118 , but allowing valves  116  to remain active. After float mode is activated, the operator can release joystick  122 . 
     Moldboard assembly  16  is pivotable about moldboard hinge knuckle  50 , so as to angle moldboard  48  in relation to the direction of travel of prime mover  12  by manipulation of joystick  122  forward or backward in relation to prime mover  12 . Manipulation of joystick  122  forward or backward sends an input signal to controller  120 . Controller  120  then directs hydraulic pressure to angle cylinder  88  via hydraulic controls  102 . Accordingly, when an operator manipulates joystick  122  forward, Moldboard assembly  16  pivots forward about moldboard hinge knuckle  50  until moldboard  48  is substantially perpendicular to the direction of travel of prime mover  12 . When an operator manipulates joystick  122  backward, moldboard assembly  16  pivots aft about moldboard hinge knuckle  50  until the discharge angle of moldboard  48  is at a maximum relative to the direction of travel of prime mover  12 . Accordingly, by adjusting the angle of moldboard  48 , the operator can change the discharge angle of the reversible wing plow  10 , thereby varying the effective swath width. 
     In addition to varying the swath width, there can be a safety function to allow moldboard  48  to automatically rotate about moldboard hinge knuckle  50  or angle back when encountering an obstacle. This is accomplished via accumulator  109  to create a hydraulic spring; however other methods, such as coil springs are also contemplated. 
     Inboard portion  56  and outboard portion  58  of moldboard  48  can pivot about folding hinge  68 , thereby allowing moldboard  48  to be folded approximately in half, or at least reducing the overall length of moldboard  48 . This folded position is intended for used primarily when in the transport mode as depicted in  FIG. 7A . 
     Reversible wing plow  10  can be put into transport mode by depressing button  124 . Transport position is used when the reversible wing plow  10  is not in use; non-use can occur when driving from one area to another or when an increased swath width is not necessary. When controller  120  receives input that button  124  has been depressed, controller  120  executes a preset program to activate the lift mode of hydraulic controls  102 . As discussed previously, upon activating the lift mode of hydraulic controls  102 , individual valves  114 ,  116  and  118  are activated and fluid pressure is directed to turning cylinders  40  and  41 , thereby retracting turning cylinders  40  and  41  until they reach their equalized point (as shown in  FIG. 5B ). Once this equalized point is reached, and no further hydraulic fluid can be displaced, a pressure spike occurs in hydraulic controls  102 . This pressure spike causes pressure sensor  117  to send a signal to controller  120 . 
     If no further operator manipulation is sensed, the controller  120  then executes a preset program to activate hydraulic controls  102  to send fluid pressure to folding cylinder  76 , thereby retracting folding cylinder  76  and pivotally folding moldboard  48  about folding hinge  68 . After a pre-programmed time has elapsed, controller  120  deactivates hydraulic controls  102 , thereby removing the pressure directed to folding cylinder  76 . 
     Controller  120  then executes a preset program to activate hydraulic controls  102  to send fluid pressure to locking cylinder  90 , causing locking pin  91  to drive forward and become seated in locking pin receiver  42  of hitch assembly  14 , thereby physically stopping any rotation of moldboard assembly  16  relative to hitch assembly  14 . Locking cylinder  90  is a safety mechanism so that even if there is a hydraulic failure, the moldboard assembly  16  will not inadvertently fall. 
     For transition from transport mode to operation mode (i.e., the driver side plowing position or the passenger side plowing position), the operator manipulates joystick  122  towards either the driver side or passenger side of prime mover  12 . Manipulation of joystick  122  activates controller  120 , which in this case, executes a preset program to activate the lift mode of hydraulic controls  102 . Upon activating the lift mode, hydraulic control  102  disengages locking cylinder  90 , thereby removing locking pin  91  from locking pin receiver  42 . Because both turning cylinders are already in the equalized point a pressure spike occurs in hydraulic controls  102 . This pressure spike causes pressure sensor  117  to send a signal to controller  120 . This input from pressure sensor  117  causes controller  120  to execute a preset program to activate the drop mode of hydraulic controls  102 . Once the drop mode is activated controller  120  takes into consideration the direction in which the operator has manipulated joystick  122 . Based on a present program, then controller  120  activates valves  114  to reverse the flow of hydraulic fluid to one of the turning cylinders  40  and  41 . The reversed turning cylinder  40  or  41  then extends, thereby overpowering the other turning cylinder  40  or  41  to continue rotation of moldboard assembly  16  in the direction that the operator has manipulated joystick  122 . 
     If the operator continues to hold joystick  122  in the same position after rotation of moldboard assembly  16  has subsided, controller  120  executes a preset program to activate the float mode of hydraulic controls  102 . The float mode removes retraction or extension pressure to turning cylinders  40  and  41 , and allows free movement of hydraulic fluid through the turning cylinders  40  and  41 , thereby allowing gravity to keep cutting edge  52  or  53  of moldboard  48  against the plowing surface, particularly in uneven terrain. Float mode is activated by deactivating individual valves  114  and  118 , but allowing valves  116  to remain active. After float mode is activated, the operator can release joystick  122 . 
     Controller  120  then executes a preset program to activate hydraulic controls  102  to send fluid pressure to folding cylinder  76 , thereby extending folding cylinder  76  and pivotally unfolding moldboard  48  about folding hinge  68 . After a preprogram time has elapsed, and moldboard  48  is fully extended, controller  120  deactivates hydraulic controls  102 , thereby removing the pressure directed to folding cylinder  76 . 
     The present invention may be embodied in other specific forms without departing from the spirit of the essential attributes thereof; therefore, the illustrated embodiments should be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention.

Technology Classification (CPC): 4