Patent Application
20140202778
1. Field of the Invention
The instant invention relates generally to a powered hitching and parking assist for a trailer.
2. Related Art
Maneuvering a vehicle in order to align a ball hitch to a trailer tongue can be a frustrating and time consuming experience. Various electrically powered and manually powered steerable trailer jacks have been described in the past. U.S. Pat. No. 3,439,264 to Kimball discloses a power caster including a three-wheeled apparatus with electric motor that is coupled to the bottom of a trailer jack tube and includes a cord that is plugged into a wall receptacle for powering the motor. U.S. Pat. No. 6,945,343 to Moreau et al. discloses an electrically driven trailer wheel mounted to the bottom of a trailer jack tube wherein a motor driven pinion is engaged with a circular rack as part of the wheel. U.S. Pat. No. 6,779,616 to Brown, discloses a motorized trailer jack with powered height adjustment means.
It is not uncommon for a 18 foot boat and trailer combination to weigh in excess of 4500 lbs. Many residential driveways have uneven surfaces, or possess an incline or downward sloping leading to an alleyway or street which complicates the hitching operation. While the aforementioned devices no doubt offer advantages over manually powered jacks when aligning a trailer tongue to a ball hitch or parking the trailer, difficulties remain. One issue is that drive chains used in many such devices are prone to breakage under load and subject to fouling with road debris. Frequent maintenance requires accessibility to the drive components in the form of partial shrouding which perpetuates the problem. Another issue is that while such devices are suitable for relatively light trailer loads on level surfaces, they are unsuited to moving heavily laden trailers or even moderately laden trailers on slippery and uneven surfaces. A dependable sure-footed means for steering boat trailers is needed.
In an aspect of the instant invention, a steerable powered trailer jack assembly includes a powering means which is preferably an electric motor powered by a dc power source, a steering means which includes a handle that swivels a lower portion of the jack assembly having a pair of wheels, and, a means of transmitting force to an axle to which wheels are fixed. The provided transmission is sealed within a housing and supported between two wheels affixed to the ends of a transverse axle extending from both sides of the housing and employs a high-torque worm drive to rotate the axle. Both wheels move in the same direction rotating with the axle. Preferably, the wheels are attached via a hub affixed to each end of the axle by bushings or other suitable means that will suggest itself to those having skill in the art.
The electric motor of the jack can be powered by a battery; whether direct connection to the battery of the towing vehicle, an extended power cord plugged into an electric jack of the towing vehicle, or by a separate battery mounted to the jack or the trailer frame. Typically, the battery will be of the 12 volt type found in vehicles and boats.
The particular characteristics of the instant invention provide an ideal solution to for boat owners when aligning and hitching heavily laden trailers.
Location of the transmission between the wheel pair, and inline with the vertical drive shaft means that the shaft is stably supported over uneven surfaces with a axle track of at least 6 inches.
The axle track of the instant invention provides sufficient traction when moving heavy trailers up or down an incline.
The components of the instant invention are compact, durable and comprise an assembly that can be detached from the frame and stowed in the vehicle, or pivoted out of the way if connected to the trailer frame with a pivoting bracket.
The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.
In the following description, the term “powered” refers to an electric powering means such as a combination of an electric motor and a power source for electric current whether ac or dc. The term “enclosed” is used interchangeably with the term “sealed” and generally refers to sealing or encasing in order to protect vulnerable parts from dust, debris and the elements. The term “axle track” refers to the distance between the center line of two wheels on the same axle. The term “high traction” refers generally to the resistance to slippage provided by the particular parts of the instant invention working together for that effect; in particular a relatively greater footprint for the wheels, the particular transmission employed, and the arrangement of the transmission and the wheels. Unless otherwise explained, any technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The singular terms “a,” “an,” and “the” include plural referents unless the context clearly indicates otherwise. Similarly, the word “or” is intended to include “and” unless the context clearly indicates otherwise. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of this disclosure, suitable methods and materials are described below. The term “comprises” means “includes.” Publications, patent applications, patents, and other references mentioned herein, if any, are incorporated by reference in their entirety for all purposes. In case of conflict, the instant specification, including explanations of terms, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.
Referring generally to
Preferably, the motive means for the disclosed embodiments is a dc driven motor, with current supplied by a battery 134 mounted on the trailer frame, or by a power cord 132 plugged into a 12v power jack of the towing vehicle, such as a trailer light jack. Conceivably however, the invention can use ac power with the use of an appropriate ac to dc adapter. It is also conceivable that a rechargeable battery pack can be used with the jack as in the case of cordless power tools. Various other configurations for powering the instant invention will suggest themselves to those having skill in the art and benefit of this disclosure.
Turning to
Depending on the connection between the support tube and the mounting plate, the entire support tube including the motor housing can swivel. In this case, rack 104 is connected at the bottom to bearing 122, but otherwise not joined to the support tube 102. Because the crank assembly is attached to the trailer frame in a fixed position by brackets 108b, the rack 104 meshed with the crank assembly 106 does not rotate when the powered jack assembly 100 is steered by handle 110, while the support tube 102, motor housing 114 and lower sub-assembly 119 turn.
It should be noted that the instant invention is generally applicable to the alignment of trailer tongue and parking of trailers, and should not be construed as being limited to boat trailers. In view of the many possible embodiments to which the principles of the disclosed invention may be applied, it should be recognized that the illustrated embodiments are only preferred examples of the invention and should not be taken as limiting the scope of the invention. Therefore, this disclosure is intended to cover such alternatives, modifications, and equivalents as may be included in the spirit and scope of the description in view of the appended drawings and claims.
