Patent Application
20060042841
The present invention generally concerns devices, systems and methods for transportation; and more particularly, in various representative and exemplary embodiments, to the towing and maneuvering of trailers, for example.
Trailers are vehicles that may be towed by another vehicle, such as for example, a small open cart or a platform used for transporting a boat. The tow engagement portion of a trailer may often be generally supported by a trailer tongue jack when the trailer is parked or otherwise disengaged with the towing vehicle.
Conventional trailer tongue jacks may be secured to a trailer tongue extension and may be configured with a baseplate at the lower end of the jack to distribute load weight over the ground. Trailer jacks are typically configured in the form of elongated shafts that have an upper portion secured to the trailer tongue extension and a lower portion that may be collapsible. A crank arm that may be rotated about the axis of the jack shaft, or in some cases about a different axis, may be employed to extend or collapse the shaft. Consequently, the elevation of the trailer tongue extension can be varied over a particular range for specific applications.
When a vehicle is re-positioned for engagement with a trailer hitch disposed on the forward end of a tongue extension, careful maneuvering for proper alignment is generally required. For example, a towing vehicle may need to back up numerous times in order to achieve suitable alignment with the trailer hitch and trailer tongue extension.
Typical trailer jacks have a 6″ hard wheel and a manual jack screw. The wheel is generally intended to allow the operator to roll the trailer manually. Due to the design of the wheels, varying transportation surfaces, and high loads on the wheel, it may often be difficult to maneuver a trailer with a conventional trailer jack. For example, backing a vehicle to a trailer and aligning the ball post of the vehicle to the trailer hitch can be quite time consuming. The wheel of conventional trailer jacks is often a poor mechanism for positioning the trailer. Moreover, wheels of existing trailer jacks generally have few features incorporated into their design for steering the jack wheel, inasmuch as most trailer jacks employ a “free castering” element.
Accordingly, a need exists inter alia to provide an improved system by which a trailer tongue extension may be maneuvered so that a trailer hitch may be suitably positioned and aligned for proper engagement with, for example, a ball post of a towing vehicle.
In various representative aspects, the present invention provides an apparatus and method for maneuvering and transporting trailers. Exemplary features are generally disclosed as including a mounting bracket adapted for attachment to a trailer; a jack shaft adapted for attachment to the mounting bracket; a wheel supported by a wheel assembly at one end of the jack shaft, wherein the wheel assembly provides rotation about the vertical axis of the shaft; a right-angle gear motor configured to provide rotary propulsion of the wheel; and a steering extension adapted to permit rotation of the wheel assembly in order to maneuver the trailer.
Additional advantages of the present invention will be set forth in the Detailed Description which follows and may be obvious from the Detailed Description or may be learned by practice of exemplary embodiments of the invention. Still other advantages of the invention may be realized by means of any of the instrumentalities, methods or combinations particularly pointed out in the claims.
Representative elements, operational features, applications and/or advantages of the present invention reside in the details of construction and operation as more fully hereafter depicted, described and claimed—reference being made to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout. Other elements, operational features, applications and/or advantages may become apparent in light of certain exemplary embodiments recited in the Detailed Description, wherein:
Elements in the Figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the Figures may be exaggerated relative to other elements to help improve understanding of various embodiments of the present invention. Furthermore, the terms “first”, “second”, and the like herein, if any, are generally used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. Moreover, the terms “front”, “back”, “top”, “bottom”, “over”, “under”, and the like, if any, are generally employed for descriptive purposes and not necessarily for comprehensively describing exclusive relative position or order. Any of the preceding terms so used may be interchanged under appropriate circumstances such that various embodiments of the invention described herein, for example, are capable of operation in orientations and environments other than those explicitly illustrated or otherwise described.
The following descriptions are of exemplary embodiments of the invention and the inventor's conception of the best mode and are not intended to limit the scope, applicability or configuration of the invention in any way. Rather, the following Description is intended to provide convenient illustrations for implementing various embodiments of the invention. As will become apparent, changes may be made in the function and/or arrangement of any of the elements described in the disclosed exemplary embodiments without departing from the spirit and scope of the invention.
A detailed description of an exemplary application, namely an apparatus and method for towing and maneuvering trailers, is provided as a specific enabling disclosure that may be readily generalized to any application of the disclosed device, system and method for transporting load articles.
In accordance with various representative and exemplary embodiments, the present invention provides a trailer tug jack (
The jack shaft may be configured with an upper portion 150 and an at least partially telescoping lower portion 130. The jack shaft may also be configured to comprise a hand crank (160, 165) at the upper end of the jack shaft 150 that may be used to articulate telescopic extension or retraction of the lower portion of the jack shaft 130 with respect to the upper portion 150. Accordingly, the elevation of the trailer tongue extension 320 may be altered in order to assist with engagement of the trailer hitch 325 with the receiving ball post 315 of the towing vehicle 300. The lower portion of the jack shaft 130 may be suitably adapted to provide for rotation of a wheel 140 and/or wheel assembly about the principle (i.e., vertical) axis of the jack shaft (150, 130). Alternatively, conjunctively and/or sequentially, the upper portion of the jack shaft 150 may be rotatably connected with the mounting bracket 120 about the principal axis (e.g., vertical axis) of the jack shaft. Configured as such an embodiment, jack shaft 130 may be made to disallow rotation about the primary axis relative to the upper portion 150 and the lower portion 130 may telescope relative to the upper portion 150 by means previously described. In general, the wheel assembly is distally disposed at the lower end of the jack shaft 130. A right-angle gear motor 100, for example, may be attached directly to the wheel 140 or to a drive gear. In the case of a drive gear, the gear may be mechanically connected with the wheel 140. In an alternative exemplary embodiment, a chain or drive belt may be configured for attachment with the drive gear and/or the wheel 140. In another representative embodiment, the drive gear may be connected with, for example, an axle gear. This may be accomplished, for example, by the drive gear directly meshing with another gear driven thereon, or alternatively, with an intermediate gear that may be employed so as to provide a mechanical advantage between the drive gear and the gear driven thereon.
High loading of wheel 140 and various surface topologies, combined with extremely high torque input and shearing action of steering, were observed to separate the wheel from the hub in several preliminary embodiments. Numerous tests were performed to determine an appropriate combination of materials to provide acceptable performance over a broad range of practical conditions. Accordingly, wheel 140 may be comprised of a machined or cast metal (e.g., aluminum, steel, etc.) hub with a relatively high tensile strength liquid cast polyurethane wheel tread on the outer portion, wherein the thickness of the polyurethane maybe up to approximately 15% to about more than 22% of the total diameter of the wheel and providing a shore hardness in the range of up to approximately 80 to about more than 95 Durometer. Alternatively, conjunctively or sequentially, the hub may be cast from any polymeric material that is suitably adapted to provide sufficient support that may be desirable for loading, torsion and adhesion. Additionally, the polymeric material may be suitably configured to comprise UV inhibitors, thereby providing another exemplary embodiment suitably adapted for outdoor use, for example. In a representative and exemplary application in accordance with one embodiment of the present invention, wheel 140 may comprise a high grade liquid cast polyurethane having a hardness in the approximate range of about 90 to about 95 Durometer (Shore A) with an elongation at break of approximately 430%, a tensile strength in the approximate range of about 7000 to about 7400 psi, a tear strength of about 700 pli. (DIE C), and an abrasion resistance on the order of about 5 to about 10 times that of standard urethane.
In accordance with an exemplary and representative embodiment of the present invention,
The wheel 140 is driven by a very high-torque, right-angle drive electric gear motor 100. The jack may be either manual or electric. In an exemplary embodiment, gear motor 100 may comprise a reversible electric gear motor. The wheel axle centerline 145 is centered to the vertical axis of the jack shaft 150, 130. The axle is keyed to both the wheel 140 and the gear motor 100 and driven directly from the gear motor 100. Alternatively, the gear motor 100 could be offset from the drive wheel and engaged to the wheel 140 via a chain, belt, sprocket and/or gear assembly. The axle rotation and loading may be transferred to the jack through axle bearings maintained in, for example, an integrated axle and gear motor support assembly 143.
Electric gear motor 100 may also be configured with a power cord 110 for delivery of electric current to gear motor 100 from a garage AC wall outlet, a battery, a power outlet of the towing vehicle, a power outlet integrated into the trailer, a power outlet integrated into a vehicle supported by the trailer and being towed by the towing vehicle, and/or the like.
The lower portion of jack shaft 130 may be configured to be at least partially collapsible with respect to the upper portion of jack shaft 150. Collar 155 general provides axial rotation of jack shaft 150 relative to mounting plate 120, alignment and containment of jack shaft (150, 130), as well as a point of attachment for mounting plate 120. Mounting plate 120 may comprise a quick-release element 125 for attachment/disengagement as well as to permit/lock pivoting of jack shaft (150, 130) about an axis substantially normal to mounting plate 120, for example.
An integrated tiller-extension/crank-arm 160 may be provided to allow for steering as well as for retracting and/or extending jack shaft 130. Configured as such an embodiment, lower jack shaft portion 130 may be made to disallow rotation about the primary axis relative to jack shaft upper portion 150 and lower portion 130 may telescope relative to upper portion 150 by means previously described. A tiller/crank handle 165 may be attached to a portion of the steering extension 160 so as to provide a steering arm (e.g., tiller) to maneuver the drive wheel 140. This may be accomplished, for example, with a center bored hole through the internal jack screw with the tiller shaft through the bore hole and affixed to the integral axle and gear motor support assembly. Alternatively the entire assembly may be rotated by affixing the tiller handle to the outer casing or assembly thereto attached and the outer casing attached to the trailer frame mount via a sleeve and bearing bracket arrangement 155, for example. The tiller may comprise drive wheel motor controls as well.
In accordance with another exemplary embodiment, as generally depicted in
As generally depicted in
The towing vehicle 300 trailer hitch (305, 315) is representatively illustrated to show a particular operating environment in which the invention may be utilized. A conventional trailer has a horizontally extending trailer tongue 320 with a trailer hitch 325 at the forward end that includes a ball post receiving well 330 for engagement with towing vehicle 300 ball post 315. Alignment problems may occur with conventional trailer jacks when attempting to connect a trailer to a vehicle; especially when the trailer hitch 325 is to be aligned above ball post 315 before the trailer may be coupled to the towing vehicle 300. Various representative and exemplary embodiments of the present invention provide improved means for interconnecting a towing vehicle 300 with a trailer hitch 325.
In the foregoing specification, the invention has been described with reference to specific exemplary embodiments; however, it will be appreciated that various modifications and changes may be made without departing from the scope of the present invention as set forth in the claims below. The specification and Figures are to be regarded in an illustrative manner, rather than a restrictive one and all such modifications are intended to be included within the scope of the present invention. Accordingly, the scope of the invention should be determined by the claims appended hereto and their legal equivalents rather than by merely the examples described above. For example, the steps recited in any method or process claims may be executed in any order and are not limited to the specific order presented in the claims. Additionally, the components and/or elements recited in any device claims may be assembled or otherwise operationally configured in a variety of permutations to produce substantially the same result as the present invention and are accordingly not limited to the specific configuration recited in the claims.
Benefits, other advantages and solutions to problems have been described above with regard to particular embodiments; however, any benefit, advantage, solution to problems or any element that may cause any particular benefit, advantage or solution to occur or to become more pronounced are not to be construed as critical, required or essential features or components of any or all the claims.
As used herein, the terms “comprises”, “comprising”, or any variation thereof, are intended to reference a non-exclusive inclusion, such that a process, method, article, composition or apparatus that comprises a list of elements does not include only those elements recited, but may also include other elements not expressly listed or inherent to such process, method, article, composition or apparatus. Other combinations and/or modifications of the above-described structures, arrangements, applications, proportions, elements, materials or components used in the practice of the present invention, in addition to those not specifically recited, may be varied or otherwise particularly adapted by those skilled in the art to specific environments, manufacturing specifications, design parameters or other operating requirements without departing from the general principles of the same.
