Abstract:
A merger apparatus including a pick-up header; a conveyor with a conveyor belt; a skid shoe disposed below the pick-up header and the conveyor; and an operative connection between the pick-up header and the skid shoe that enables the merger apparatus to articulate independently of an external frame underneath the conveyor, such that loose material transported by the conveyor belt that lags beneath the return side may fall to the ground keeping the return side of the conveyor belt free from obstructions.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. application Ser. No. 14/798,184 filed Jul. 13, 2015, which claims the benefit of priority from U.S. Provisional Application No. 62/037,992 filed Aug. 15, 2014, the entire contents of each of which are herein incorporated by reference. 
    
    
     BACKGROUND OF THE DISCLOSURE 
     Field of the Disclosure 
     The present disclosure relates to windrow merger assembly including a pick-up header for lifting material from the ground. In agricultural applications, the pick-up header may be utilized on the merger to lift material, such as crops, from a field and then transfer the material to a belt-type conveyor. The conveyor may then shift the material laterally to form a windrow that can later be picked up. 
     Description of the Related Art 
     In related art, a machine including a pick-up header may have skid shoes disposed beneath the pick-up header to maintain a minimum clearance between the ground and the pick-up header. A machine  300  related to the present disclosure is illustrated in  FIGS. 7A-E , and includes a pick-up header  301  with an external frame  303 . Skid shoes  305  are mounted to the external frame  303  at attachment points  307 . The skid shoes  305  may be adjustable to allow for changing field and/or crop conditions. In particular, the skid shoes  305  may be adjusted to allow the pick-up header  301  to be very close to the ground to maximize crop capture. The skid shoes  305  may also be adjusted to increase the distance between the pick-up header  301  and the ground in order to clear obstacles, such as rocks, or leave an undesirable portion of the crop. 
     The skid shoes  305  must be mounted to the external frame  303  of the pick-up header  301  in some manner. In the typical configuration of the related art, the external frame  303  is positioned beneath a belt  309  along with the attachment points  307  that the skid shoes  305  mount to. As a result, the external frame  303  creates catch points in areas  310  above the external frame  303  that can trap material falling from the belt  309 . Trapped material can slow or stop the rotation of the belt  309  and create uneven crop distribution reducing efficiency and feed quality. If enough material builds up, it can eventually lead to damage of the machine  300  and/or field. The external frame  303  also takes up room beneath the machine  300 , reducing ground clearance and increasing the risk of contact with the terrain. 
     SUMMARY OF THE DISCLOSURE 
     In one aspect of the disclosure, a merger apparatus is provided which includes a pick-up header, a conveyor with a conveyor belt, and a skid shoe disposed below the pick-up header and the conveyor. The merger apparatus may include an operative connection between the pick-up header and the skid shoe that enables the merger apparatus to be free of an external frame underneath the conveyor. 
     In another aspect of the disclosure, a merger apparatus for lifting and conveying material is provided. The merger apparatus may include a pick-up header, a horizontal frame member, and a conveyor positioned between the pick-up header and the horizontal frame member in a front to rear direction of the merger apparatus. A plurality of skid shoes positioned below at least one of the pick-up headers and the conveyor may be provided along with a main pivot shaft operatively connected to at least one of the pick-up headers and the horizontal frame member. In one aspect of the disclosure, a first space may be provided between the conveyor and the skid shoes in a vertical direction, and a second space may be provided between the conveyor and a surface that the skid shoes rest on to support the merger apparatus. The skid shoes may be mounted on the main pivot shaft and at least one of an angle of the skid shoes and a vertical position of the pick-up header may be adjusted with a rotational movement of the main pivot shaft. In one aspect of the disclosure, material remaining on a conveyor surface that faces the surface may fall directly through the first space and the second space without being obstructed. 
     In another aspect of the disclosure, a pick-up header is provided to include a plurality of pick-up teeth, a header frame, a lower rear frame member extending from the header frame in a front to rear direction of the pick-up header on an opposite side of the header frame as the pick-up teeth. A plurality of support plates may be mounted to the lower rear frame member, and the main pivot shaft may be positioned on the side of the pick-up frame with the lower rear frame member. In one aspect of the disclosure, a plurality of bearings may be attached to the support plates and rotatably support the main pivot shaft. At least one skid shoe may be mounted to each shaft end of the main pivot shaft. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more complete appreciation of the invention and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, wherein: 
         FIGS. 1A-1C  illustrate an exemplary embodiment of a windrow merger assembly including several mergers according to the present disclosure. 
         FIGS. 2A-2C  illustrate an exemplary embodiment of a merger according to the present disclosure. 
         FIG. 3  illustrates a perspective view from behind an exemplary embodiment of a merger according to the present disclosure without a conveyor belt. 
         FIG. 4  illustrates a bottom view of an exemplary embodiment of a merger according to the present disclosure without a conveyor belt. 
         FIG. 5A-5B  illustrate exemplary parts of an internal structure of an exemplary embodiment of a merger according to the present disclosure. 
         FIG. 6A-6C  illustrate an exemplary system of linkages for an exemplary embodiment of a merger according to the present disclosure. 
         FIGS. 7A-7E  illustrate multiple views of a merger related to the present disclosure. 
         FIGS. 8A-8B  illustrate a side view of a merger having a skid shoe positioned at different angles of articulation. 
         FIGS. 9A-9B  illustrate side views of another embodiment of a merger related to the present disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring now to the drawings, wherein like reference numerals designate identical or corresponding parts throughout the several views. It is noted that as used in the specification and the appending claims the singular forms “a,” “an,” and “the” can include plural references unless the context clearly dictates otherwise. 
     The following description relates to a pick-up header and a merger including the pick-up header, and a conveyor, which are supported by skid shoes that rest on the ground. The skid shoes may be attached to a frame member of the pick-up header and/or a main pivot shaft which may be connected to a system of linkages. In exemplary embodiments including the main pivot shaft and the system of linkages, an elevation of the pick-up header and an orientation of the skid shoes may be adjusted with an operation of the system of linkages. The system of linkages may be positioned within components of a pick-up header frame, a conveyor frame, and a merger frame. 
     During operation, material that is picked up by the pick-up header and conveyed in a longitudinal direction of the merger may remain on a conveyor belt on a return side of the conveyor. With the skid shoes attached to the frame of the pick-up header and/or the main pivot shaft, an arrangement of the skid shoes, with or without the main pivot shaft and the system of linkages, may not require an external frame to be provided beneath the conveyor in exemplary embodiments of a merger according to the present disclosure. As a result, material that lags on the return side of the conveyor may fall to the ground keeping the return side of the conveyor belt free from obstructions. 
     Windrow Merger Assembly 
       FIGS. 1A-C  illustrate an exemplary embodiment of a windrow merger assembly  1  according to the present disclosure that is supported by wheels  3  on the ground and may be towed by a vehicle (not shown) via a tongue  5  extending from a trailer  7 . As illustrated in  FIG. 1B , the windrow merger assembly  1  includes mergers  100  operably connected to the trailer  7  that is supported by the wheels  3 . Arms  9  extend from behind a deflector  101  mounted to vertical frame members  103  of each merger  100 . The arms  9  extend over a conveyor  130  of each merger  100  and attach to a bar  11 , from which guides  13  extend. The guides  13  extend from the bar  11  over a plurality of pick-up teeth  151  between end plates  153  of a pick-up header  150  according to the present disclosure. The pick-up teeth  151  are positioned to alternate with pick-up guards  155  on a front of the pick-up header  150  along a longitudinal direction (X axis) of the merger  100  ( FIG. 1C ). At least one of the end plates  153  may support a drive shaft (not shown) which transfers rotational force to drive the plurality of pick-up teeth  151 . Skid shoes  170  are provided under each merger  100 . During operation, the skid shoe  170  may contact the ground to maintain a minimum clearance (S) between the ground and the pick-up header  150  as illustrated in  FIG. 2A . 
     Merger 
       FIGS. 2A-2C  illustrate the merger  100  including the pick-up header  150  according to the present disclosure in more detail. As illustrated in  FIG. 2A , a deflector  101  is mounted on the vertical frame members  103  of the merger  100 . The vertical frame members  103  are attached to a horizontal frame member  105  as illustrated in  FIGS. 2A and 2B , which extends in the longitudinal direction (X axis) of the merger  100 . The conveyor  130  is positioned between the horizontal frame member  105  of the merger  100  and the pick-up header  150 . 
     As illustrated in  FIGS. 2A and 2C , the conveyor  130  includes a conveyor belt  131  that is driven to rotate around the merger  100  to convey material on a top side  130   a  in the longitudinal direction (X axis) of the merger  100 . The conveyor belt  131  may be an endless conveyor belt driven by rollers and supported by a frame as described in more detail below. 
     Because a frame is not provided under a return side  130   b  of the conveyor  130 , lagging material does not fall and accumulate on a structural element immediately below the conveyor belt  131 . Thus, an issue of material accumulating and forming catch points that may slow or stop the conveyor  130  may be avoided with the merger  100  of the present disclosure. 
     Pick-up Header 
       FIGS. 3 and 4  illustrate various aspects of the pick-up header  150  according to the present disclosure. The pick-up header  150  includes a header frame  157 . One side of the header frame is attached to the pick-up teeth  151  and the pick-up guards  155 , and an opposite side is attached to the conveyor  130 , which extends in the longitudinal direction (X axis) of the merger  100  between the endplates  153  ( FIG. 4 ). The conveyor  130  is attached to the header frame  157  just above a lower rear frame member  159  and below an upper rear frame member  161 . The lower rear frame member  159  and the upper rear frame member  161  extend in the longitudinal direction (X axis), while projecting from the pick-up header  150  in a front to rear direction (Z axis) of the merger  100  ( FIG. 1C ). 
       FIG. 3  further illustrates support plates  163  positioned under a longitudinal guide  165  mounted onto the lower rear frame member  159  of the header frame  157 . The support plates  163  help support the main pivot shaft  180 . 
     Individual guide members  167  are attached to the header frame  157  below attachment points for cross members ( 135   a   1 ,  135   a   3 ) of the conveyor  130  described in more detail below. The conveyor belt  131  (see  FIGS. 2A and 2C ) may fit in a space defined between the longitudinal guide plate  165  and the individual guide members  167 , such that a movement of the conveyor belt  131  is guided by the guide members  167  in the longitudinal direction (X axis). The guide members  167  also prevent an inner side of the conveyor belt  131  from contacting lower sides of the cross members ( 135   a   1 ,  135   a   3 , and  134 ), which could impede the movement of the conveyor belt  131 . 
     Conveyor 
       FIGS. 3-5A  describe the present disclosure having an internal structure of the merger  100  including an internal structure of the conveyor  130 . 
       FIG. 3  illustrates a perspective view from a back of the merger  100  similar to  FIG. 2C , and  FIG. 4  illustrates a bottom view of the merger  100  according to the present disclosure. In  FIGS. 3 and 4 , the conveyor belt  131  is removed in order to show primary rollers  133  and a conveyor frame ( 134 ,  135   a   1 ,  135   a   2 ,  135   b ) of the conveyor  130 . 
     Primary rollers  133  are positioned on opposite ends of the merger  100  in the longitudinal direction (X axis). A drive mount  137  is connected on to a rear of the horizontal frame member  105  in a location corresponding to one of the primary rollers  133 . The drive mount  137  connects to the primary roller  133  in order to rotate the primary roller  133  and drive the conveyor belt  131  (see  FIGS. 2A and 2C ). 
     As illustrated in  FIG. 5A , the conveyor frame ( 134 ,  135   a   1 ,  135   a   3 ,  135   b ) includes first cross members  135   a   1  and second cross members  134  extending in the front to rear direction (Z axis) and attached to the pick-up header frame  157  and the horizontal frame member  105 . The first and second cross members ( 135   a   1 ,  134 ) support horizontal cross members  135   b  extending in the longitudinal direction (X axis). A surface belt rides on the horizontal cross member  135   b , which also connects to the conveyor cross members  135   a   1 ,  135   a   3 , and  134 . The first and second cross members ( 135   a   1 ,  134 ) attach the deflector  101  ( FIG. 2A-2C ), vertical frame members  103 , and horizontal frame member  105  to the pick-up header  150  ( FIGS. 1 and 3 ) and support the overall structure of the merger  100  ( FIG. 2A ). 
     System of Linkages 
     A description of the arrangement of a system of linkages ( 180 - 200 ) and is provided with reference to  FIGS. 2B, 5A, 5B, 6A, and 6B . 
       FIGS. 5A and 5B  illustrate an embodiment of the system of linkages ( 180 - 200 ), including a main linkage  181  extending in the front to rear direction (Z axis), the main pivot shaft  180 , and a linear actuator  200 .  FIG. 5A  illustrates the merger  100  according to the present disclosure without the deflector  101  and the pick-up teeth  151 , and shows the main pivot shaft  180  and the main linkage  181  of the system of linkages ( 180 - 200 ). The main pivot shaft  180  is attached to each skid shoe  170 , and the main linkage  181  extends through the horizontal frame member  105  at one end, and the header frame  157  at an opposite end. 
       FIG. 5B  illustrates the merger  100  according to the present disclosure without the deflector  101 , the pick-up teeth  151 , or portions of header frame  157  including the lower frame member  159 . A first linkage arm  185  is also shown attached to the first pivot plate  183  by a linkage arm pin  183   b  ( FIG. 5B ). The first linkage arm  185  extends through a second opening  157   b  in the header frame  157  ( FIG. 5A ), to connect with a first connection member  187  by a first connection pin  187   a  ( FIG. 5B ). The first pivot plate  183  is connected to the first linkage arm  185  in order to translate the motion of the main linkage  181  to the main pivot shaft  180  via the first connection member  187 . 
     A connection between the main linkage  181  and the main pivot shaft  180  is described with reference to  FIGS. 5A, 5B, 6A, and 6B . The main linkage  181  extends within the conveyor unit  130  in the front to rear direction (Z axis). Specifically, the main linkage  181  is positioned between the first cross members  135   a   1  along the longitudinal direction (X axis), and attaches at one end to a first pivot plate  183 . The main linkage  181  extends through a header frame opening  157   a  ( FIG. 5A ), to attach to the first pivot plate  183  positioned in front of the header frame  157  in the front to rear direction (Z axis) as shown in  FIG. 5B . The main linkage  181  is attached to the first pivot plate  183  with a first main linkage pin  183   a.    
       FIGS. 6A and 6B  illustrate respective connections between the main linkage  181 , first pivot plate  183 , first linkage arm  185 , and first connection member  187  by the first main linkage pin  183   a , linkage arm pin  183   b , and first connection pin  187   a . As illustrated in  FIGS. 5B, 6A, and 6B , the first linkage arm  185  may be connected to the main pivot shaft  180  by the first connection member  187 . In other embodiments, the first linkage arm  185  may be directly connected to the main pivot shaft  180 . 
       FIG. 6B  is an exemplary embodiment according to the present disclosure, the main pivot shaft  180  may extend in the longitudinal direction (X axis) and be attached to second connection members  189  positioned at or near shaft ends  180   a  of the main pivot shaft  180 . 
     In one embodiment, two connection members  189  may be connected symmetrically at one end to the main pivot shaft  180 , and the other ends of the connection members  189  may be connected to pivot members  173  that are connected to the skid shoe  170 . A second linkage arm  191  may be connected to another pivot member  173  at one end, and support plates  163  ( FIGS. 5A, 5B ) at the other end. The support plates  163  may also be connected to the  159  lower rear frame member and aid in the support of the longitudinal guide plate  165 . 
     In addition, to the shaft ends  180   a , the second connection members  189  may be positioned at intermediate positions on the main shaft  180  between the first connection member  187  and the shaft ends  180   a . The second connection members  189  may attach the main pivot shaft to the skid shoes  170  by connecting to respective pivot members  173  described in detail below. In addition, a second linkage arm  191  may connect one of the support plates  163  ( FIGS. 5A, 5B ) to one of the pivot members  173  ( FIGS. 6A-6C ) of the skid shoe  170 . The support plates  163  also aid in the support of the longitudinal guide plate  165  ( FIGS. 3 and 5A ). Bearings  182  may be provided to support the main pivot shaft  180  in rotation. The bearings  180  may be ball bearings, roller bearings, oil-film bearings, or any other type of appropriate bearing. 
     Further, the bearings  182  may be provided near the shaft ends  180   a  of the main pivot shaft  180  and in a vicinity of the first connection member  187  that is attached to the first linkage arm  185 . In addition, the bearings  182  may be attached to support plates  163  ( FIGS. 5A-5B ) that may be positioned in locations corresponding to the shaft ends  180   a  of the main pivot shaft  180 . 
     A connection between the main linkage  181  and the linear actuator  200  is described with reference to  FIGS. 2B, 5A, 5B, 6A and 6B . An end of the main linkage  181  ( FIG. 5B ) passes through both a merger frame opening  105   b  ( FIG. 2B ), and a frame slot  105   a  ( FIG. 5A-5B ) mounted on the horizontal frame member  105 . 
     With reference to  FIGS. 5A and 5B , the linear actuator  200  may be provided at a rear of the conveyor  130 . This location of the linear actuator  200  may provide easier access for manual adjustment of the skid shoe  170 . The linear actuator  200  may be actuated manually or may be powered. The linear actuator  200  may be mechanical, hydraulic, electrical, or pneumatic. For example, the linear actuator  200  may include a ball screw, a solenoid, hydraulic cylinder, pneumatic cylinder, or a combination thereof. Further, the linear actuator  200  may be manually controlled or electronically controlled by a controller (not shown). The linear actuator  200  may move in a vertical direction (Y axis) which is identified in  FIG. 6A , and may be connected to the main linkage  181 . The actuator is a linear applicator or a pivot, or a rotary actuator. 
     As illustrated in  FIGS. 6A and 6B , the system of linkages ( 180 - 200 ) includes a first pivot pin  195  extending through the first pivot plate  183 , and a second pivot pin  197  extending through the second pivot plate  193 . The first pivot pin  195  is provided to mount the first pivot plate  183  on to the pick-up header frame  157  ( FIG. 5A ) such that the first pivot plate  183  can rotate about an axis perpendicular to the front and rear direction (Z axis) and parallel to the longitudinal direction (X axis). The second pivot pin  197  is provided to mount the second pivot plate  193  on to the pick-up header frame  105   a  ( FIG. 5A ) such that the second pivot plate  193  can rotate about another axis perpendicular to the front and rear direction (Z axis) and parallel to the longitudinal direction (X axis). The actuator for this application could be any type of linear actuator or a pivot could be replaced with a rotary actuator. 
     The embodiment shown ( FIG. 2C ) is a manual screw type linear actuator. The housing is rotated causing the internal screw to either extend or retract. 
       FIGS. 6A and 6B  illustrate the system of linkages ( 180 - 200 ) without the pick-up header frame  157  or the horizontal frame member  105  of the merger  100 . The main linkage  181  is attached to a second pivot plate  193  by a second main linkage pin  193   a . A linkage actuator pin  193   b  attaches the second pivot plate  193  to the linear actuator  200 , while a second pivot pin  197  attaches the second pivot plate  193  to the horizontal frame member  105 . 
     In other embodiments, the linear actuator may be provided in the system of linkages in place of any of the linkage members that operate in a linear manner, including the main linkage  181 . Replacing one of the linkages with the linear actuator may reduce the number of linkages in the system. In one embodiment shown in  FIG. 9A , a linear actuator  200  may be connected to the first connection member  187 , which is connected to and controls the rotation of the main pivot shaft  180 . The linear actuator  200  to operate or replace linkages may comprise, but is not limited to, a hydraulic, pneumatic, or mechanical system, or some combination thereof. 
     Skid Shoes 
       FIGS. 6A-6C  describe skid shoes  170 . The skid shoes  170  may be provided beneath the conveyor  130  ( FIG. 1A ) and the pick-up header  150  ( FIG. 3 ), and may include a flat portion  170   a , like a flat plate, and angled lip portions  170   b  on opposite sides of the flat portion  170   a  in the front to rear direction (Z axis). The flat portion  170   a  may include a flat lower surface which may contact the ground. Each skid shoe  170  may include at least one pivot member  173  for connecting the skid shoe  170  to the main pivot shaft  180 . Further, a plurality of pivot members  173  may be provided on each skid shoe  170  in exemplary embodiments according to the present disclosure. 
     As illustrated in  FIGS. 6B and 6C , each pivot member  173  may be provided on a reinforcement member  171  which provides increased stiffness and rigidity to the skid shoe  170 . The reinforcement member  171  may attach to the angled lip portions  170   b  of the skid shoe  170 . In other exemplary embodiments, the pivot members  173  may be mounted directly to the flat portion  170   a  of the skid shoe  170 . During operation, each skid shoe  170  may contact the ground to maintain the minimum clearance (S) between the ground and the pick-up header  150  illustrated in  FIG. 2A . 
     Exemplary Operation 
     An exemplary operation of the skid shoes  170  and system of linkages ( 180 - 200 ) according the present disclosure will now be described. 
     The linear actuator  200  may be provided to actuate at least one linkage in the system of linkages ( 180 - 200 ). The main linkage  181  may be driven by the linear actuator  200  so as to move in a linear direction, such as the front to rear direction (Z axis). Specifically, the movement of linear actuator  200  will cause the second pivot plate  193  to rotate so that the main linkage  181  may move in the front to rear direction (Z axis), as shown in  FIG. 6A . As previously provided, the second pivot plate  193  is rotatably connected to the horizontal frame member  105  of the merger  100  ( FIG. 2C ). 
     The movement of the main linkage  181  in the front to rear direction (Z axis) as shown in  FIGS. 5A and 5B , will be translated to the main pivot shaft  180  by the first pivot plate  183 , the first linkage arm  185  and the first connection member  187 . Specifically, the first pivot plate  183  will rotate relative to the pick-up header frame  157 , causing the first linkage arm  185  to move in the front to rear direction (Z axis). An end of the first linkage arm  185  connected to the first connection member  187  is rotatable about the first connection pin  187   a . As a result of this connection, the movement of the first linkage arm  185  in the front to rear direction (Z axis) causes the first connection member  187 , and thereby the main pivot shaft  180 , to rotate in a rotational direction (R) identified in  FIG. 2A . 
     The first linkage arm  185  can move back and forth along the front to rear direction (Z axis). As such, the direction of rotation of the main pivot shaft  180  corresponds to the direction movement of the main linkage  181  and the first linkage arm  185  along the front to rear direction (Z axis), shown in  FIG. 6A . When the main linkage  181  moves towards the pick-up teeth  151 , the first linkage arm  185  moves towards the deflector  101 , and the main pivot shaft  180  rotates in a first rotational direction (R 1 ) as illustrated in  FIG. 6A . When the main linkage  181  moves towards the deflector  101 , the first linkage arm  185  moves towards the pick-up teeth  151 , and the main pivot shaft  180  rotates in a second rotational direction (R 2 ) as illustrated in  FIG. 6A . 
     When the main pivot shaft  180  rotates due to the movement of the main linkage  181 , the position of the skid shoe  170  is adjusted due to the connections between second connection members  189  and respective pivot members  173 , and with second linkage arms  191  which are connected to respective pivot members  173  ( FIG. 6B ). The adjustment of the skid shoe  170  may include a change in its angle and/or a change in vertical displacement. According to one exemplary embodiment, rotation of the main pivot shaft  180  in the first rotational direction (R 1 ) may vertically lower the skid shoe towards the ground, and rotation of the main pivot shaft  180  in a second rotational direction (R 2 ) may vertically raise the skid shoe away from the ground ( FIG. 6A ). Further, rotation of the main pivot shaft  180  in one rotational direction may increase an angle between the skid shoe  170  and the ground, and rotation of the main pivot shaft  180  in another rotational direction may decrease the angle between the skid shoe  170  and the ground. In other embodiments, the angle and the vertical displacement of the skid shoe  170  may both be changed depending on the rotational direction of the main pivot shaft  180 . The linkage member  191  may attach to a support plate  163  in a parallel linkage arrangement, maintaining a constant angle between the shoe and the bottom of the merger throughout the range of adjustment. The support plate  163  may be slotted which allows for the change in the angle of the shoe for improved ground following. In one embodiment, the end of at least one joint of the second linkage arm  191  has a slot  201  ( FIGS. 8A-8B ), allowing adjustment of the angle the skid shoe  170  makes with the horizontal. 
     As illustrated in  FIGS. 1A-6C , and described herein, multiple skid shoes  170  may be connected to the main pivot shaft  180 . The rotation of the main pivot shaft  180  due to the movement of the main linkage  181  may adjust the position of each of the multiple skid shoes  170 . The skid shoes  170  may be provided near each shaft end  180   a  of the main pivot shaft  180  ( FIG. 6B ). 
     Multiple second connection members  189  may connect the main pivot shaft  180  to multiple pivot members  173  ( FIG. 6C ). As illustrated in  FIGS. 6B and 6C , for each skid shoe  170 , multiple second linkage arms  191  may be arranged in parallel with one second connection member  189  to form a four bar linkage, the second linkage arm  191  connected directly to the support plate  163  and one of the pivot members  173 . The rotation of the main pivot  180  shaft may change the displacement of the skid shoe  170  relative to the bottom of the pick-up header  150  with the movement of the second linkage arm  191 . 
       FIGS. 8A-8B  illustrate the pick-up header  150  and conveyor  130 , connected to the skid shoe  170 . The position and movement of the skid shoe  170  may be controlled by the system of linkages, detailed in  FIGS. 6A-6C , or by a linear actuator  200 , as shown in  FIG. 9A , to pivot the second pivot plate  193  about the second pivot pin  197 , which translates rocking motion into linear movement of the main linkage  181  along the Z axis, which in turn actuates the linear movement of the first linkage arm  185  by rocking the first pivot plate  183 . As a result of the linear motion of the first linkage arm  185  acting on the first connection member  187 , the main pivot shaft  180  rotates and moves the second connection member  189  and second linkage arm  191 , which cause the skid shoe  170  to move vertically. 
     The embodiments of  FIGS. 9A-B  depict the result of rotating the main pivot shaft  180  to move the skid shoe  170  to different positions. 
     In one position, the skid shoe  170  is in a flat, lowered position of vertical displacement (A) due to rotation of the main pivot shaft  180  in the direction R 2 , as shown in  FIG. 9A . In another position the skid shoe  170  is in a flat, extended position of vertical displacement (A+B) due to rotation of the main pivot shaft  180  in the direction R 1 , as shown in  FIG. 9B . 
     The rotation of the skid shoe  170  about the angles Θ and α is due to contact between the skid shoe  170  and the ground surface as the skid shoe  170  passes over uneven terrain. The skid shoe  170  is free floating. The angular position of skid shoe  170  is independent of the adjustment of the pivot shaft  180  and movement of the main linkage  181 . The center of gravity of the skid shoe  170  is located rearward of the leading pivot member  173 , which causes the skid shoe  170  to maintain a standard rotation angle Θ of greater than zero, with the leading edge of the skid shoe  170  at an elevation above that of the trailing edge to help prevent the leading edge from digging into the ground when the pick-up header  150  is returned to the ground. 
       FIG. 8A  shows the skid shoe rotating to an angle (Θ), generally zero to 12 degrees from the horizontal as allowed by the slotted member  191  to permit the shoe to follow the contour of the ground.  FIG. 9B  shows the result of rotating the linkage in the R 1  direction. The shoe lowers to raise the pick-up header  150  from the ground.  FIG. 8B  shows the ground following capabilities in the opposite direction to that shown in  FIG. 8A  with the skid shoe rotating to an angle (α), generally zero to 5 degrees from the horizontal. 
     As illustrated in  FIGS. 6A and 6B , the system of linkages ( 180 - 200 ) includes a first pivot pin  195  extending through the first pivot plate  183 , and a second pivot pin  197  extending through the second pivot plate  193 . The first pivot pin  195  is provided to mount the first pivot plate  183  on to the pick-up header frame  157  ( FIG. 5A ) such that the first pivot plate  183  can rotate about an axis perpendicular to the front and rear direction (Z axis) and parallel to the longitudinal direction (X axis). The second pivot pin  197  is provided to mount the second pivot plate  193  on to the pick-up header frame  105   a  ( FIG. 5A ) such that the second pivot plate  193  can rotate about another axis perpendicular to the front and rear direction (Z axis) and parallel to the longitudinal direction (X axis). The actuator for this application could be any type of linear applicator or a pivot could be replaced with a rotary actuator. 
     The embodiment shown ( FIG. 2C ) is a manual screw type linear actuator. The housing is rotated causing the internal screw to either extend or retract. 
       FIGS. 6A and 6B  illustrate the system of linkages ( 180 - 200 ) without the pick-up header frame  157  or the horizontal frame member  105  of the merger  100 . The main linkage  181  is attached to a second pivot plate  193  by a second main linkage pin  193   a . A linkage actuator pin  193   b  attaches the second pivot plate  193  to the linear actuator  200 , while a second pivot pin  197  attaches the second pivot plate  193  to the horizontal frame member  105 . 
     Portions of the system of linkages ( 180 - 200 ) may be located within the conveyor  130  and surrounded by the conveyor belt  131 . In one embodiment, the merger frame opening  105   b  may be provided in the horizontal frame member  105  of the merger  100 , and the main linkage  181  may pass through the merger frame opening  105   b  to be substantially provided inside the conveyor  131 . Further, in the exemplary embodiments of merger  100  and pick-up header  150  according to this disclosure, one end of the main linkage  181  passes through the merger frame opening  105   b  and the other end of the main linkage  181  passes through the pick-up header frame opening  157   a  ( FIG. 5A ). 
     With the main linkage  181  substantially provided inside the conveyor  130 , the main pivot shaft  180  and the skid shoe  170  may be disposed below the conveyor  130  and behind the pick-up header  150 . The main pivot shaft  180  may be disposed outside of the conveyor  130 , and the support plates  163  may contact against the lower rear frame member  159  of the pick-up header  150  ( FIG. 5A ). With this configuration, the main linkage  181  may be free from obstructions below the conveyor belt  131  and may still allow for adjustment of the skid shoe  170 . In some embodiments, equipped with linkages described, any or all of the components could be positioned outside the conveyor except for the  181 . 
     In another embodiment, the skid shoe  170  may be fixed to a support on the pick-up header frame  157  or the lower rear frame member  159  of the pick-up header frame  157 . The skid shoes  170  may be fixed such that the skid shoes  170  are not adjustable. In other exemplary embodiments, the skid shoes may be attached to the pick-up header  157  and adjustable at an attachment point. The skid shoe  170  in this configuration may be adjusted directly by a mechanical device or remotely by remote control. The attachment point may include a ball-and-socket joint, a servo, a ratchet joint, or a pin joint. 
     In other embodiments, the skid shoes  170  may be replaced with at least one roller. The roller may be fixed or ground following. 
     Although only certain embodiments of this invention have been described in detail above, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiment without materially departing from the novel teachings and advantages of this disclosure. Accordingly, all such modifications are intended to be included within the scope of this disclosure. Further, it is to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.