Technical Field

The present invention relates generally to the towing field and, more particularly, to a trailer hitch receiver including a hitch ball that is locked in position on a ball mount head to prevent relative rotation between the mounting stem of the hitch ball and the ball mount head.

Background of the Invention

Trailer hitches including a hitch ball for connecting a towing vehicle to a trailer have long been known in the art. Examples of such are disclosed in a number of patents including, for example, U.S. Patents 3,482,856 to Reese; 3,694,006 to Goode et al. ;

3,768,837 to Reese; 4,033,601 to Lindahl et al . and 5,375,867 to Kass et al .

Most hitch balls are mounted to the ball mount head of a trailer hitch receiver by means of a threaded mounting stem and cooperating locking nut or nut and lock washer. More specifically, the threaded mounting stem extends through an aperture in the ball mount head and the locking nut or nut and locking washer are

snugly tightened against the ball mount head to secure the trailer hitch ball in position. While this provides a very adequate connection, many individuals are frustrated when the threaded mounting stem of the hitch ball rotates in the ball mount head when attempting to tighten the securing nut. When this occurs, it is not possible to complete the tightening operation unless tools are employed to prevent it from happening. One way of addressing this problem is disclosed in U.S. Patent 5,040,817 to Dunn. In Dunn, the pedestal or upper portion of the hitch ball mounting stem includes wrench flats that allow the ball to be held in position with a wrench during the nut tightening operation. While this is a functional solution to the problem, it must be appreciated that this involves the manipulation of two tools, one wrench to secure the hitch ball from rotation and one wrench to tighten the securing nut . Many individuals find the manipulation of two tools inconvenient or difficult. Further, two appropriate tools are not always readily available to allow the connection to be made.

Recognizing these and other shortcomings, a need is hereby identified for an improved structural arrangement whereby a mounting stem of a hitch ball may be secured from rotation relative to the ball mount head during connection of the hitch ball thereto.

Summary of the Invention

Accordingly, it is a primary object of the present invention to provide a system for securing a hitch ball to a ball mount head that prevents rotation of the

mounting stem of the hitch ball relative to the ball mount head during the installation operation in a simple and convenient manner overcoming the limitations and disadvantages of the prior art . Yet another object of the present invention is to provide a method for preventing relative rotation between the mounting stem of a hitch ball and a ball mount head to which the hitch ball is to be attached during the fastening of the hitch ball to the ball mount head.

Another object of the present invention is to provide a trailer hitch wherein the mounting stem of the hitch ball includes a locking element for engaging in an acircular outline define by a mounting aperture in the ball mount head so as to prevent rotation of the mounting stem relative to the ball mount head. In this way it is advantageously possible to secure the hitch ball to the ball mount head by means of a securing nut and by utilizing only a single tool. Additional objects, advantages and other novel features of the invention will be set forth in part in the description that follows and in part will become apparent to those skilled in the art upon examination of the following or may be learned with the practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

To achieve the foregoing and other objects, and in accordance with the purposes of the present invention as described herein, an improved trailer hitch is provided. The trailer hitch includes a hitch bar adapted for receipt in a receiver box of a trailer hitch receiver of a type well known in the art that is

mounted to a towing vehicle . The trailer hitch also includes a ball mount head that is mounted to or integrally formed with the hitch bar. The ball mount head includes a mounting aperture having a sidewall that defines an acircular outline. Additionally, the trailer hitch includes a hitch ball including a threaded mounting stem carrying a locking element for engaging within an acircular outline defined by the mounting aperture sidewall. Advantageously, this snug male/female interconnection prevents rotation of the hitch ball mounting stem relative to the ball mount head.

The trailer hitch also includes a fastener for securing the hitch ball to the ball mount head. Preferably, the fastener is a lock nut or nut and cooperating lock washer that is received on the threaded mounting stem which depends from the hitch ball. As should be appreciated, the engagement between the locking element on the mounting stem of the hitch ball and the sidewall of the mounting aperture on the ball mount head prevents rotation of the hitch ball mounting stem as the nut is tightened to secure the hitch ball in position. This prevention of rotation is achieved without the use of any additional tools so that mounting may be completed. This is far more convenient for an individual and, accordingly, the structural arrangement significantly enhances user satisfaction.

In accordance with still another aspect of the present invention a method is provided for preventing relative rotation of a hitch ball mounting stem with respect to a ball mount head during the fastening of the hitch ball to the ball mount head. The method comprises the steps of providing an acircular aperture

in the ball mount head and a mounting or cooperating acircular locking element on the hitch ball mounting stem. Essentially the locking element nests within and mates or engages with the sidewall that defines the mounting aperture. As described above, this arrangement prevents relative rotation between the hitch ball mounting stem and the ball mount head so that the hitch ball may be easily secured utilizing a single tool for tightening the fastening member. Still other objects of the present invention will become apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.

Brief Description of the Drawings

The accompanying drawing incorporated in and forming a part of the specification, illustrates several aspects of the present invention and together with the description serves to explain the principles of the invention. In the drawing:

Figure 1 is an exploded perspective view showing the trailer hitch of the present invention; Figure 2 is a detailed, partially cross-sectional view showing the hitch ball secured in the ball mount

head; and

Figure 3 is a bottom plan view of the hitch ball showing one configuration of a locking element that may be utilized.

Reference will now be made in detail to the present preferred embodiment of the invention, an example of which is illustrated in the accompanying drawing.

Detailed Description of the Invention

Reference is now made to Figure 1 showing the trailer hitch 10 of the present invention. As shown, the trailer hitch 10 includes a draw bar, generally designated by reference numeral 12. Draw bar 12 comprises an integral ball mount head 14 and hitch bar 16. As is known in the art, the ball mount head 14 receives a hitch ball 18 and the hitch bar 16 is adapted for receipt in a trailer hitch receiver of a type well known in the art that is mounted to a towing vehicle. Such a trailer hitch receiver is, for example, available from Reese Products, Inc. under various trademarks including the Shadow Mount Class I and II Series hitch receivers, the Insta-Hitch Class II series receiver, the Omni II Multifit Class II Series receiver, the Class III and IV 35 and 36 Series receivers and the Titan Class V receiver.

It should be appreciated that the draw bar 12 being shown and described is merely being presented for purposes of illustration and the present invention is not to be limited thereto. More specifically, the ball mount head 14 and hitch bar 16 may not be integral but may in fact be separate, attachable components. For

example, the ball mount head and hitch bar may comprise part of a weight distributing hitch such as disclosed in, for example, U.S. Patent 5,375,867 to Kass et al . Further, the hitch bar 16 may not be adapted for receipt in the receiver box of a trailer hitch receiver. It may simply comprise an integral portion or component of a vehicle mounted hitch having a ball mount head especially adapted to directly receive a hitch ball 18. Such a construction is also well known in the art as embodied by the Custom Welded Class I, 75 and 76 Series hitches sold by Reese Products, Inc. With reference back to Figure 1, it should be appreciated that the ball mount head 14 is provided with a mounting aperture 20 having a sidewall 21 defining an acircular outline. A hexagonal shape is illustrated. It should be appreciated, however, that substantially any acircular shape could be provided including but not limited to square, triangle, pentagon, six point star, eight point star, twelve point spline, rectangle, oval, ellipse, keyed, flat keyed and radius cross.

As further shown in Figure 1, the hitch ball 18 includes a locking element 22. The locking element 22 includes an acircular outline substantially corresponding to but slightly smaller than the acircular outline defined by the mounting aperture 20. Thus, it should be appreciated that when the hitch ball 18 is secured in the ball mount head 14, the locking element 22 engages within the acircular outline defined by the sidewall 21 of the mounting aperture 20. This serves to prevent rotation of the hitch ball 18 relative to the ball mount head 14 (see also Figure 2) . As will be described in greater detail below, this simple structure that is relatively inexpensive to

manufacture provides added convenience for an individual seeking to secure a hitch ball 18 to a ball mount head 14.

More specifically, as shown, the hitch ball 18 includes a mounting stem 24 defined by the locking element 22 and a depending threaded shank 26. As best shown in Figure 3 , it should be appreciated that the locking element 22 and threaded shank 26 are axially aligned and the sidewall of the locking element 22 radially projects outward beyond the sidewall defined by the threaded shank. Accordingly, sufficient clearance is provided to allow the threaded shank 26 to be inserted through the mounting aperture 20 while the locking element 22 is sized sufficiently large to properly engage and nest against the sidewall 21 of the mounting aperture. Once so positioned, the hitch ball 18 may be secured in position by means of a cooperating lock washer 27 and nut 28 being tightened on the threaded shank 26. More specifically, the individual utilizes one hand to provide a slight downward force on the top of the hitch ball 18. This securely holds the hitch ball 18 down on the ball mount head 14 with the locking element 22 snugly received in the mounting aperture 20. At the same time, the lock washer 27 is placed on the nut 28 is hand tightened on the threaded shank 26. While maintaining the downward pressure on the hitch ball 18, a wrench or other appropriate tool may then be utilized to properly torque the lock nut 28 thereby securing the hitch ball in position (again see Figure 2) .

Of course, in order to insure proper connection it must be appreciated that the depth of the locking element 22 must be equal to or less than the thickness of the sidewall 21 of the mounting aperture 20 in the

ball mount head 14. Further, the lock washer and nut 28 must be of sufficient expanse to fully overlap the locking element 22 and engage the ball mount head 14. While a cooperating lock washer 27 and nut 28 are shown for purposes of illustration, it should be appreciated that a lock nut may be utilized with or without a standard washer if desired.

In summary, numerous benefits result from employing the concepts of the present invention. By providing an acircular mounting aperture 20 in the ball mount head 14 and providing a cooperating acircular locking element 22 on the hitch ball 18, it is possible to prevent relative rotation between the hitch ball mounting stem 24 and the ball mount head during fastening of the hitch ball to the ball mount head. More specifically, the locking element 22 engages within the acircular aperture 20 in the ball mount head 14 so as to prevent relative rotation of the mounting stem 24 as the nut 28 is tightened to secure the hitch ball 18 in position. The disclosed structure is simple and inexpensive to manufacture. It advantageously allows an individual to properly secure a hitch ball 18 to a ball mount head 14 with the use of only a single wrench. The mounting stem 24 of the hitch ball 18 is automatically secured against rotation to allow convenient and efficient fastening of the hitch ball in position.

Still other objects of the present invention will become apparent to those skilled in this art from the following description wherein there is shown and described a preferred embodiment of this invention, simply by way of illustration of one of the modes best suited to carry out the invention. As it will be realized, the invention is capable of other different

embodiments and its several details are capable of modification in various, obvious aspects all without departing from the invention. Accordingly, the drawings and descriptions will be regarded as illustrative in nature and not as restrictive.