CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to, and the benefit of, pending U.S. patent application Ser. No. 14/991,098 (now U.S. Pat. No. 9,751,369) filed on Jan. 8, 2016, which in turn claimed priority to, and the benefit of, U.S. Provisional Patent Application No. 62/102,291 filed on Jan. 12, 2015. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The invention relates generally to an improved coupler for a trailer hitch and more specifically relates to an improved trailer hitch coupler with moveable arms which provide ease of coupling without requiring precise alignment between the towing vehicle and the trailer. 
       BACKGROUND ART 
       [0003]    As used herein, the term “trailer” is used in a broad sense to describe unpowered vehicles that are towed by a separately powered vehicle. Commonly used trailers include utility trailers (often ranging from 4×6 to 10×20), boat trailers, campers, etc. Conventionally, the towing vehicle will include a hitch, secured to the frame of the towing vehicle, that includes a ball head, although other configurations are known. The trailer will include a coupler to placed over the ball head (or other configuration) and secured in place. 
         [0004]    However, many trailers can be very heavy and difficult to maneuver by hand. Thus, the towing vehicle must be accurately, and precisely, position against the trailer to hook the trailer up to the towing vehicle. The hitch itself is often out of the drivers view while in the towing vehicle. Thus, assistance from someone outside of the towing vehicle is needed, or the driver must get out of the towing vehicle, check the position, and get back into the towing vehicle multiple times, a time consuming and potentially dangerous process. What is needed is trailer hitch coupler that provides an easier coupling between the trailer and hitch, and provides a secure attachment to the towing vehicle. 
       SUMMARY OF THE INVENTION 
       [0005]    In view of the foregoing disadvantages inherent in the conventional type of methods and systems now present in the prior art, the present invention provides an improved trailer hitch coupler. Because the predominant trailer hitch is the ball head hitch, the specification describes the preferred embodiment configured to receive and secure to a ball hitch. However, those of skill in the art will recognize that invention can also be used with other hitch configurations. 
         [0006]    In one embodiment, the invention comprises a trailer tongue having a recessed portion forming a cavity, a cavity spring forward biasing a base plate, with movable coupler arms attached to the base plate, which can extend to an open position to receive a ball hitch, and when in a closed position around the ball hitch, can move into the recessed portion. 
         [0007]    In some embodiments, a locking arm can be used, with or without locking arm springs, that can engage a saddle in the coupler arms to lock the coupler arms in a closed position, and recessed into the recessed portion of the trailer tongue. 
         [0008]    When the coupler arms are in their open position, it provides a much larger target area for the hitch, and when closed provides a secure connection to the towing vehicle. 
         [0009]    Other objects and advantages of the present invention will become obvious to the reader and it is intended that these objects and advantages are within the scope of the present invention. 
         [0010]    To the accomplishment of the above and related objects, this invention may be embodied in the form illustrated in the accompanying drawings/pictures, recognizing however, that the drawings are illustrative only, and that changes may be made in the specific construction illustrated and described within the scope of the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0011]    It should be noted that identical features in different drawings are shown with the same reference numeral. Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings. 
           [0012]      FIG. 1  is a cut away side view of one embodiment of the trailer hitch coupler. 
           [0013]      FIG. 2  is a top view of one embodiment of the trailer hitch coupler with the coupler arms in an open position. 
           [0014]      FIG. 3  is a front view of one embodiment of the trailer tongue without the coupler arms depicted. 
           [0015]      FIG. 4  is a side view of an embodiment of the trailer hitch coupler in a closed and locked position. 
       
    
    
     DETAILED DESCRIPTION 
       [0016]    The following component parts (with designations), that may be found, or used, in various embodiments of the present invention, include: 
         [0017]    Trailer hitch coupler  5   
         [0018]    Trailer tongue  10   
         [0019]    Tongue recessed portion  20   
         [0020]    Recessed portion back wall  25   
         [0021]    Recessed portion front  27   
         [0022]    Locking arm  30   
         [0023]    Locking arm pivot point  40   
         [0024]    Cavity spring  50   
         [0025]    Cavity spring rear  53   
         [0026]    Cavity spring front  57   
         [0027]    Base plate  60   
         [0028]    Locking arm spring  70   
         [0029]    Moveable coupler arms  80   
         [0030]    Ball recessed portion  90   
         [0031]    Coupler arms pivot point  100   
         [0032]    Coupler arm outer face  110   
         [0033]    Coupler arm inner face  120   
         [0034]    Coupler arm top face  122   
         [0035]    Coupler arm bottom face  123   
         [0036]    Coupler arm front edge  125   
         [0037]    Saddle  130   
         [0038]    Coupler arm opening spring  135   
         [0039]    Coupler arm/base plate connector pin  140   
         [0040]    Locking lip  145   
         [0041]    Base plate extension  150   
         [0042]      FIGS. 1 through 4  illustrate various views and embodiments of the present invention. In one embodiment of the trailer hitch coupler  5 , shown in  FIG. 1 , a trailer tongue  10  is provided. The trailer tongue  10  can be manufactured as part of the trailer itself, or as a separate attachment to be added to existing trailers. As discussed above, common trailers include utility trailers, boat trailers, campers, etc. The trailer tongue  10  of  FIG. 1  has a recessed portion  20  forming a cavity on the inside of the trailer tongue  10 . The trailer tongue  10  and the recessed portion  20  can be of various configurations, but preferably is rectangular or square in cross-section, as most traditional trailer tongues. 
         [0043]    In the embodiment shown in  FIG. 1 , inside the recessed portion  20  is a cavity spring  50 . The cavity spring rear  53  is secured inside the recessed portion  20 , for example, pressed against the recessed portion back wall  25  inside the recessed portion  20 , or against flanges inside the recessed portion  20  (not shown). The cavity spring front  57  interfaces with a base plate  60 , the cavity spring  50  biased, and pushing the base plate  60  toward, the recessed portion front  27 . The recessed portion front  27  can have a lip or flanges to keep the base plate  60  inside the recessed portion  20 . Thus, when not in use, the cavity spring  50  is biased such that the base plate  60  rests toward the recessed portion front  27 , but the base plate  60  is compressible, against the cavity spring  50 , into the recessed portion  20  (see  FIG. 4 ). The base plate  60  is preferably of the same approximate, but slightly smaller, cross section as the recessed portion  20  so it can move freely inside the recessed portion  20 . 
         [0044]    Referring to  FIGS. 1 and 2 , the trailer hitch coupler  5  may also provide a locking arm  30  that can be secured to the trailer tongue  10  at locking arm pivot point  40 . The locking arm  30  is moveable from open and closed positions, and pivots around the pivot point  40 . The locking arm  30  can be secured at the pivot point  40  using any convention means, but should remain movable as described herein. The locking arm  30  moves generally in an arc in a vertical direction due to the secured pivot point  40 . 
         [0045]    Referring to  FIGS. 1 and 3 , in this embodiment, a locking arm spring  70  can be positioned on, and one end connected or secured to, the outer side face of the trailer tongue  10 , preferably forward of the locking arm pivot point  40 . The other end of the locking arm spring  70  is connected or secured to the locking arm  30 . In some embodiments, no locking arm spring  70  is used. In another embodiment, a locking arm spring  70  is used on both sides of the trailer tongue  10  (as shown in  FIG. 3 ). Preferably, the locking arm spring  70  is biased to pull the locking arm  30  in a downward position. However, the locking arm spring  70  should allow for a user to be able to pull the locking arm  30  upward without too much force. Additionally, the cavity spring  50  should be sized to exert more force on the base plate  60  (to push the base plate  60  and the coupler arms  80 ) forward than the force of the locking arm spring  70  pulling the locking arm  30  down. Thus, once the coupler arms  80  are unlocked or unlatched (as described further below), the preferred natural position is for the base plate  60  to rest against the recessed portion front  27 , the coupler arms  80  extended in their open position, and the locking arm  30  resting against the coupler arm top face  122 . This is due, in this embodiment, to the preferred downward bias of the locking arm spring  70 . 
         [0046]    Referring to  FIGS. 1 and 2 , the trailer hitch coupler  5  may also have moveable coupler arms  80  that are attached, via one or more pivot points  100  (e.g., pivot pins), to the base plate  60 . In one embodiment shown in  FIG. 2 , the base plate  60  may have base plate extensions  150  extending outwardly from the base plate  60 , and containing a hole or cavity. Preferably, the top and the bottom of the base plate  60  each have two (2) base plate extensions  150 . The holes in the base plate extensions  150  can correspond to holes or channels in the coupler arms  80  such that a coupler arm/base plate connector pin  140  (or bolt, tube, or other securing mechanism) can be placed through the hole in the base plate extension  150  and holes/channels in the coupler arms  80 , thus creating the pivot point  100 . This allows the coupler arms  80  to move to and from an open position and closed position. The coupler arms  80  can also be spring biased such that the coupler arms  80  are in an open position when not in use by using an optional coupler arm opening spring  135  (see  FIGS. 1 and 2 ). The coupler arms  80  have an outer face  110  and an inner face  120 . The coupler arm inner face  120  may have a ball recessed portion  90 , that are generally half a sphere configured and sized to receive a standard ball hitch. Standard ball hitches come in various sizes, so the ball recessed portion may be sized to accommodate anywhere from 1½″, 1¾″, 1⅞″, 2″, 2 5/16″, or any other standard size. For other hitch configurations, the coupler arm inner face  120  may be configured and sized to receive other shapes. The coupler arms  80  may also have top face  122  that includes a cut-out over the ball recessed portion  90 , or it may cover the ball recessed portion  90 . The coupler arms  80  also have a bottom face  123  that may include a cut-out configured and sized to accommodate the shank of the trailer hitch ball assembly. Thus, many standard ball hitches use a 1″ shank, and thus the coupler arm bottom face  123  could include a ½ inch, or slightly larger, half circle cut out of the coupler arm bottom face  123  to wrap around and secure to the hitch assembly, while still allowing the hitch assembly to rotate within the cut-out. The coupler aim front edge  125  may have a saddle  130  to receive the locking arm  30 . The saddle  130  may be configured to have a locking lip  145  (see  FIGS. 1 and 4 ) to engage or catch the locking all  130  to retain the locking arm  30  in place. The coupler arm front edge  125 , or saddle  130  (if used), on one or both of the extension arms can also include a separate latch, clip, or lock to secure the locking arm  30  in place. 
         [0047]      FIG. 4  depicts an embodiment of the trailer hitch coupler  5  in its closed and locked position. The cavity spring  50  has been compressed in the tongue recessed portion  20 , the coupler arms  80  are in a closed position, and the majority of the coupler arms  80  positioned inside the tongue recessed portion  20 . The coupler arm front edge  125  and saddle  130  extends outside of the recessed portion front  27 , allowing the locking arm  30  to be moved or pulled into the saddle  130 . 
         [0048]    In practice, when not in use, the coupler arms  80  are preferably biased in an open position, and spread apart. In a preferred embodiment, the coupler aims  80  are spread apart forming an angle of between 40-90 degrees. The spread of the coupler arms  80  provides a wider target for the tow hitch. When a vehicle with a tow hitch is backed toward the open coupler arms  80 , the coupler aims  80  force the ball hitch toward the base plate  60  resting against the recessed portion front  27 . As the ball hitch engages the base plate  60 , it compresses the cavity spring  50  into the recessed portion  20 . As the base plate  60 , and the attached coupler aims  80  move into the recessed portion  20 , the side walls of the trailer tongue  10  force the coupler arms  80  to close around the hitch. The coupler arms  80  are sized such that in their closed position, they can slide into the recessed portion  20  of the trailer tongue  10  (e.g., the height of the coupler arms, measured from the bottom face to the top face, is less than the height of the tongue recessed portion front  27 ). The recessed portion  20  and cavity spring  50  are sized such that the base plate  60 , and the majority of the coupler arms  80  slide back into the recessed portion  20 , with the saddle  130  on the coupler arm front edge  125  extending out of the recessed portion  20 . The locking arm  30  can be moved into the saddle  130  to keep the coupler arms  80  from sliding out of the recessed portion. The locking aim  30  and/or the coupler arms  80  can also use holes or recesses to receive conventional pins or locking mechanisms to secure in a particular position. For example, holes can be provided in the side walls of the trailer hitch coupler  5 , and a pin or locking mechanism slid through the side wall, through the holes in the locking arm  30  or coupler arms  80 , and out the other side of the side wall of the trailer hitch coupler  5 . Additionally, a pin or locking mechanism can be used on holes in just the coupler arm front edge  125  that extend out of the recessed portion  20 .
This application provides an improved trailer hitch coupler comprising a trailer tongue having a recessed portion, said recessed portion having a recessed portion front and recessed portion back wall; a moveable base plate inside the tongue recessed portion; a cavity spring positioned in the tongue recessed portion and biasing the base plate toward the recessed portion front; and coupler arms connected to the base plate at a pivot point, whereby the coupler arms rotate around the pivot point to open and closed positions.