As vehicles become smaller due to public demand for increased fuel economy, the space available in said vehicles for storage of goods, such as when traveling a long distance, is substantially reduced. For this reason, it is now quite common to mount various racks and other enclosed carriers on the vehicle roof in order to provide additional storage space when transporting substantial quantities of goods, such as when vacationing. However, such roof-mounted racks and enclosures have numerous recognized disadvantages, such as the difficulty of access and the substantial reduction in fuel economy.
Hence, there is an increasing need for some type of structure which can be provided in conjunction with small vehicles and which can provide additional storage capacity in those situations when needed. Such device is believed already available in the form of a one-wheel trailer, such trailers having been known for a long period of time. A one-wheel trailer has recognized advantages in that the driver of the vehicle does not have to worry about maneuvering of the trailer, such as when backing up, and hence such trailer in many instances is an ideal structure for providing additional storage capacity. Further, such trailers can be extremely light in weight so as to not impose any significant drag on the vehicle, and provide convenient access to the storage space therein.
While such single-wheel trailers have been known for a long time, nevertheless such trailers have never been extensively accepted or utilized, and it is believed that this is due primarily to the highly specialized and complex hitch arrangement required for connecting such trailer to a vehicle. For example, most single-wheel trailers employ a single or double tongue arrangement having a pair of clamping devices which are fixedly clamped directly to the bumper at spaced locations therealong, whereby the two clamping devices and their connections to the vehicle bumper hence provide the necessary stabilization for the trailer. Such an arrangement is illustrated by U.S. Pat. Nos. 3,784,230 and 2,157,186. The use of such bumper attachments is undesirable for numerous reasons. For example, the bumpers on most vehicles lack the strength necessary for permitting the clamping devices to be directly attached thereto, and hence do not have the necessary strength to properly withstand the towing forces being imposed directly thereon. Further, many bumpers are an intricate part of the styling of the vehicle, and hence are painted or formed of or coated with plastic, and hence are easily damaged if clamping devices are mounted thereon. Further, the bumpers of the many different vehicles have many different configurations and sizes, and thus providing the trailer tongue with brackets thereon capable of fitting such a wide range of bumper configurations is substantially impossible. Further, some bumpers are designed such that it is virtually impossible to mount a clamp directly thereon. Hence, the use of single-wheel trailers, particularly the known type trailers employing a pair of bumper clamps, is hence wholly impractical based on an evaluation of the bumper construction of most modern vehicles.
Accordingly, the present invention relates to an improved trailer hitch arrangement designed specifically for a single-wheel trailer, which hitch arrangement overcomes the disadvantages associated with prior known structures as described above, and hence makes use of such single-wheel trailers a highly desirable and in fact practical alternative with modern vehicles, including small vehicles.
In the present invention, there is provided an improved hitch arrangement which makes use of the standard trailer hitch (such as a Class I hitch) commonly present on many vehicles, which standard hitch is most instances has the hitch bar attached directly to the frame but in many instances makes use of a special bumper mount. The present invention provides a special hitch adapter which can be easily attached directly to the existing hitch bar on the vehicle. The hitch ball is initially removed, and the hitch adapter is then fixedly attached to the hitch bar by being bolted thereto, which bolt utilizes the hole already existing in the hitch bar. The hitch adapter has a crossbar at the rearward end thereof, which crossbar mounts thereon a pair of couplers, specifically a pair of conventional hitch balls, whereby the one-wheel trailer can then have a double tongue arrangement provided with conventional ball-receiving couplings so as to be connected to a pair of spaced hitch balls. In this manner, the single-wheel trailer can be connected directly to the already-existing hitch bar which is fixedly attached to the vehicle. Hence, the single-wheel trailer can thus be coupled to virtually any vehicle, particularly since many vehicles already have a trailer hitch mounted thereon, and the resulting hitch arrangement provides for vertical motion between the car and the trailer, as necessary for negotiating inclines and the like, but also provides a rigid connection between the car and the trailer so as to prevent horizontal articulation therebetween, whereby the trailer is thus provided with the required stability.
In the improved hitch adapter of this invention, the forward end of the adapter preferably has a channel-shaped configuration so as to snugly accommodate therein the hitch bar as mounted on the vehicle, which channel-shaped configuration hence prevents relative twisting or pivoting between the adapter and the hitch bar in both horizontal and vertical planes, whereby direct bolting of the adapter to the hitch bar thus results in a strong and rigid connection. This adapter is, in the preferred embodiment, T-shaped so as to be provided with a horizontal crossbar at the rearward end of the base leg, which crossbar adjacent the free ends thereof mounts thereon the two hitch balls for cooperation with the hitch couplers on the trailer. The crossbar is normally disposed at an elevation substantially above the front end of the base leg so that the latter is disposed at the elevation required for connection to the hitch bar, whereas the crossbar is at a higher elevation to accommodate the greater height of the trailer tongues associated with one-wheel trailers.
In the improved adapter of this invention, a one-wheel trailer can be easily and efficiently attached to or disconnected from a vehicle without requiring any direct connection to the bumper, and at the same time the hitch adapter provides for an extremely strong and rigid connection to permit solely the necessary vertical articulation between the trailer and vehicle. The hitch adapter is extremely small and compact to facilitate both the handling and storage thereof. The provision of a pair of standard hitch balls on the adapter, and cooperating standard couplers on the trailer, hence greatly facilitates the attachment of the trailer to the vehicle, or the detachment of the trailer from the vehicle when desired.
Other objects and purposes of the invention will be apparent to persons familiar with devices of this general type upon reading the following specification and inspecting the accompanying drawings.