Abstract:
The latch assembly for the wings of a folding tool bar includes catches on each wing wing and a pair of pivotal latch arms on the tool bar tongue. An actuator pivots the latch arms between an unlatched position disengaged from the wing catches to a latched position engaging the wing catches so as to retain the wings in a transport position. In the latching and unlatching method, the latch arms are pivoted simultaneously in opposite directions by an actuator to capture and release the opposing wings of the tool bar.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority under 35 U.S.C. §119 to provisional application U.S. Ser. No. 62/218,630, filed on Sep. 15, 2015, herein incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    Folding toolbars are well known. Conventional folding toolbars include a longitudinally extending tongue having a transverse frame member at the rear of the tongue. A pair of wings are pivotally attached to the frame so as to fold between a use position extending laterally in opposite directions, and a transport position extending parallel and adjacent the tongue. The wings and the center frame each have wheels for rolling support in both the use and transport positions. Folding and unfolding of the wings is accomplished with hydraulic cylinders. 
         [0003]    Typically, the wings are maintained in the transport position solely by the hydraulic system, without a mechanical lock or latch. Sometimes the hydraulic cylinders do not fully pull the wings into the transport position. Since the hydraulic cylinder is located at the inner/rearward ends of the wings, the outer/forward ends of the wings tend to have lateral movement in the transport position. Such movement creates additional forces or stress on the toolbar components and the hydraulic system, which can lead to premature wear and the need for repair or replacement. 
         [0004]    Therefore, a primary objective of the present invention is the provision of a latch assembly for securing the wings of the toolbar in the transport position. 
         [0005]    Another objective of the present invention is the provision of a latch assembly for a folding toolbar which can be quickly and easily actuated for engaging and disengaging the toolbar wings in the transport position. 
         [0006]    A further objective of the present invention is the provision of a latch assembly for the wings of a folding toolbar, with the latch assembly being hydraulically actuated. 
         [0007]    Still another objective of the present invention is the provision of a linearly actuated latch assembly for folding tool bar wings and retention of the wings in the transport position. 
         [0008]    Yet another objective of the present invention is the provision of a pivotal latch assembly for retention of opposing wings on a folding tool bar. 
         [0009]    Still another objective of the present invention is the provision of a latch assembly for the opposite wings of a folding tool bar which utilizes a pair of latches for retentively engaging a pair of catches on the wings of the tool bar. 
         [0010]    Another objective of the present invention is a method of latching the wings of a folding tool bar in a transport position. 
         [0011]    A further objective of the present invention is the provision of latching and unlatching folding tool bar wings by simultaneously pivoting a pair of latch arms to and from engagement with hooks on the wings. 
         [0012]    Still another objective of the present invention is the provision of a method of latching and unlatching folding tool bar wings by pivoting a pair of latches in unison between latched and unlatched positions. 
         [0013]    Yet another objective of the present invention is the provision of a method of latching and unlatching folding tool bar wings in a transport position by pivoting latch arms in opposite directions relative to one another. 
         [0014]    A further objective of the present invention is the provision of a method of latching and unlatching opposing wings of a folding tool bar using a linear actuator. 
         [0015]    Another objective of the present invention is the provision of a latching assembly and method for folding toolbar wings, which is quick, easy and safe to use, and economical to manufacture. 
         [0016]    These and other objectives will become apparent from the following description of the invention. 
       SUMMARY OF THE INVENTION 
       [0017]    A latch assembly is provided for a folding tool bar having a central tongue and opposite wings foldable between a lateral use position and a longitudinal transport position. The latch assembly includes a catch on each of the wings and a pair of latches mounted on the tool bar tongue. The latches extend in opposite lateral directions and are moveable between a latched position to retentively engage the catches on the wings to retain the wing in the transport position and an unlatched position disengage from the catches to allow the wings to fold open to the use position. The latches are pivoted simultaneously, or in unison, between the latched and unlatched positions by an actuator. 
         [0018]    A method of latching and unlatching folding tool bar wings is accomplished by folding the wings from a lateral use position to a longitudinal transport position, and then pivoting a pair of latch arms mounted on the tool bar tongue from an unlatched position disengaged from the wings to a latched position engaging catches or hooks on the wings so as to secure the wings during transport of the tool bar. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  is a perspective view of a toolbar having the wings folded to a transport position and having the latch assembly according to the present invention. 
           [0020]      FIG. 2  is an enlarged front perspective view of the latch assembly in an unlatched position. 
           [0021]      FIG. 3  is an enlarged upper perspective view of the latch assembly in an unlatched position. 
           [0022]      FIG. 4  is a rear perspective view of the latch assembly in an unlatched position. 
           [0023]      FIG. 5  is another upper perspective view of the latch assembly in an unlatched position. 
           [0024]      FIG. 6  is a left front perspective view of the latch assembly in a latched position. 
           [0025]      FIG. 7  is a right front perspective view of the latch assembly in a latched position. 
           [0026]      FIG. 8  is a front elevation view of the latch assembly in a latched position. 
           [0027]      FIGS. 9 and 10  are perspective views of the base or mounting bracket of the latch assembly. 
           [0028]      FIG. 11  is an exploded view of the base. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0029]    A folding toolbar is designated in the drawings by the reference numeral  10 . The toolbar  10  includes a longitudinally extending tongue  12 , with a central frame  14  extending transversely at the rear end of the tongue  12 . A pair of wings  16  are pivotally mounted adjacent the center frame  14  so as to be moveable between a folded transport position parallel and adjacent to the tongue  12 , as shown in  FIG. 1 , and an unfolded use position extending substantially perpendicular to the tongue  12 . The center frame  14  and wings  16  are supported by wheels  18 . 
         [0030]    The above-described general components of the toolbar  10  are conventional, and do not constitute a part of the present invention. 
         [0031]    The present invention is directed towards a latch assembly  20  to secure and retain the wings  16  in the folded, transport position. More particularly, the latch assembly  20  includes a pair of latch members  22  pivotally mounted on the tongue  12  for movement between a latched position engaging catches  24  mounted on the wings  16 , and an unlatched position disengaged from the catches  24 . 
         [0032]    Each latch member  22  includes a first inner arm  26  having an inner end pivotally mounted between a pair of spaced apart, upright parallel plates  28  by a pin  30  which defines a first pivot axis. Each arm  26  comprises a pair of spaced apart, parallel plates  27 . The arms  26  extend laterally outwards in opposite directions from the mounting plates  28 . The outer end of each arm  26  is pivotally mounted to a second outer arm  32  by a pin  34  which defines a second pivot axis. Each arm  32  comprises a pair of spaced apart, parallel plates  33 . The pin  34  resides between the upper inner end and lower outer end of the outer arm  32 . 
         [0033]    Pivotal movement of the latch members  22  is controlled by a linear actuator, such as a hydraulic cylinder  36  having an extendable rod  38 . The hydraulic cylinder  36  is mounted to the upper or inner end of one of the arms  32  by a pin  40 , while the rod  38  is pivotally mounted to the upper or inner end of the other arm  32  by a pin  42 . 
         [0034]    Each wing catch  24  includes a hook  44  which is releasably engaged by a pin  46  on the outer ends of the respective arms  32 . 
         [0035]    As seen in the drawings, the plates  27  of the arms  26 , the plates  33  of the arms  32  and the mounting plate  28  are formed as a parallelogram with opposite sides and ends. However, it is understood that a different configuration for these components can also be utilized without departing from the scope of the present invention. 
         [0036]    In operation, the wings  16  are folded from the extended use position to the transport position in a conventional manner. Then, the hydraulic cylinder  36  is actuated to pivot the latch members  22  from the disengaged, unlatched position shown in  FIGS. 2-5  to the engaged latched position shown in  FIGS. 6-8 . Extension of the rod  38  pivots the outer arms  32  about the axis defined by the pins  34 , such that the upper ends of the arms  32  are pushed outwardly and the outer ends of the arms  32  are moved inwardly to engage the pins  46  into the hooks  44  of the catches  24 . During this latching function, the arms  32  pull the respective wings  16  inwardly adjacent the tongue  12 , as the arms  32  pivot about the pins  34 . The latching function of the latch assembly  20  secures the wings  16  in the transport position via the pins  46  of the latch arms  32  engaging the latch hooks  42 . 
         [0037]    To unlatch the wings  16 , the hydraulic cylinder  36  is actuated to retract the rod  38  to pivot the outer arms  32  about the axis defined by the pins  34 , such that the upper ends of the outer arms  32  are pulled inwardly and the pins  46  on the outer ends of the arms  32  are disengaged from the hooks  44  on the catches  24 . 
         [0038]    The latch arms  32  pivot in unison between the latched and unlatched positions. This simultaneous pivotal movement of the latch arms in opposite directions by the actuator minimizes latching and unlatching time. 
         [0039]    As an alternative to the hydraulic cylinder  36  and rod  38 , the actuator can be a telescoping rod extended and retracted by an electric motor, a threaded coupler extended and retracted by an electric motor, or other structure connected between the arms  32  to move the arms between the latched and unlatched positions. 
         [0040]    The mounting plates  28  for the latch arms  26  are connected by a base plate  50 , as shown in  FIGS. 9-11 . Each plate  28  has an inner plate  52  welded thereto, with a pair of recesses  54  formed in each plate  52 . The terminal ends  56  of the recesses form stop elements which retain the latch arms  26  in a raised position when the cylinder  36  is retracted to unlatch the wings  16 . Since the cylinder  36  is not symmetrical or equally balanced at the center of the mounting plates  28 , the inner plates  52  maintain the arms  26  substantially horizontal, as seen in  FIG. 2 , and prevent the arms  26  from dropping. Such lateral dropping of either arm  26  could preclude the associated latch arm  32  from disconnecting from the associated wing  16 . Such drooping of either arm  26  could also interfere with latching of the folded wing. Thus, the arms  26  are stationary and support the pivotal latch arms  32 . 
         [0041]    The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.