Patent Application
20090067968
The present invention relates to a lifting device for use with a truck or other vehicle having a platform or bed for carrying objects. More particularly, the invention relates to a lifting device that is adapted to be removably attached to a vehicle trailer hitch or the like and which is capable of lifting loads under hydraulic or other power.
One of the most useful and popular vehicles today is the pickup truck, both for commercial and hobby activities. As part of the acceptance of pickups, not only for general transportation, hauling, top-cover carrying of tools and camping supplies, and pulling trailers and the like, is the desire for versatility. Of primary importance is the ability to use the bed of the pickup as a platform for hauling heavy objects.
Since pickup trucks have a load-rated hauling level much greater than one or two humans can quickly load into the bed, it has become desirable to be able to quickly and efficiently lift heavy objects into the pickup. Examples of loads are farm supplies such as animal feed, seeds and fertilizers, and the like. Hay bales are a common product carried by pickup trucks.
The prior art does not disclose a simple device supported on the centerline hitch of a vehicle to lift loads without resort to complicated, expensive or elaborate mechanisms. None of the prior art provides a simple device for insertion into an existing trailer hitch by one person working alone, whereby the device is capable of easily lifting and loading up to at least 800 pounds or more without assistance. Particularly, no prior device exists for lifting large loads within a space not much larger than the area taken by the vehicle itself other than a hydraulic device shown in my Lifting Device, U.S. Pat. No. 6,042,328, issued Mar. 28, 2000.
There is one device, shown in my U.S. Pat. No. 6,024,328, which can be attached to an existing trailer hitch and can lift objects on to a pickup truck bed. This device uses a hydraulic motor to generate the power needed to lift the arm in a vertical path to move objects from the ground to the truck bed or back. The problem with the hydraulic motor design is that it is expensive to manufacture, requires maintenance and additional safety features to prevent failure of the hydraulic cylinder during operation. The truck battery driven pump, lock valves, fluid flow controls and the rod fed hydraulic cylinder are all costly. Users who are not familiar with hydraulics experience maintenance difficulties. The other problem with this prior art design is that it is limited to lifting in a vertical path and thus can only load or unload off the back of the vehicle.
Accordingly, it is an object of the present invention to provide a lifting device for use with a pickup truck or other similar platform that allows objects to be loaded and unloaded to the back and over the sides of the vehicle.
Another object of this invention is to provide a lifting device that is easily attached to a vehicle, such as a pickup truck, by one individual of average strength, yet which device does not use hydraulic forces.
Other objects will appear hereinafter.
It has now been discovered that the above and other objects of the present invention may be accomplished in the following manner. Specifically, the present invention provides a lifting device for attachment to a trailer hitch or the like on a pickup truck or other vehicle. The device can also be mounted on stationary platforms, since the movement of the truck or other vehicle doesn't form part of the invention.
The lifting device includes a lifting boom having one end over the hitch and a second end having a lifting arm centered over the cargo bed for lifting a load. The one end is attached to a vertical member that extends down to the general level of the hitch, where it mates with a side arm extending to the hitch.
The second end of the lifting boom is mounted to the vertical member and defining a pivot point, and the lifting boom pivots by a linear actuator through an arc to and from being centered over the cargo bed to a proximate the ground on which the vehicle sits. A stabilizing column forming a link between the linear actuator and the vertical member and supports the linear actuator during at least a portion of its movement of the lifting boom. A rotating power means such as a cordless electric drill drives the linear actuator to cause the movement through the arc.
In a preferred embodiment, the stabilizing column is a telescoping column adapted to extend as the lifting boom moves from the first position to the second position. Also preferred is a rotating support adapted to move the vertical member about the axis defined by the vertical member to permit the lifting boom to, swivel in a horizontal plane from over the cargo bed of the vehicle.
For a more complete understanding of the invention, reference is hereby made to the drawings, in which:
As shown in the drawings, the present invention is used with a vehicle 10, such as a pickup truck, with a cab 11 and sides 15. The device includes a lifting boom 17 that is preferably L-shaped at one end extending down on to vertical member 43 as seen in
The vertical member 43 extends down to about level with the hitch 39 on truck 10 and is attached to a side arm 41 which engages hitch 39 with hitch engaging member 37, as best seen in
The lifting boom 17 moves through an arc illustrated in part by arrow 31 in
Stabilizing column 27 helps support linear actuator 19 in the first part of its movement, and the actuator 19 moves through arc 57 while the lifting boom 17 moves through arc 31 which extends 160 degrees and thus more than shown in
The lifting device of this invention is admirably suited for use with a pickup truck and has shown great versatility in, for example, various construction and farming applications as well as with hobbies and general hauling tasks. Typical loads include motorized vehicles such as motorcycles, four-wheelers, golf carts and the like, as well as building supplies, garden supplies, furniture, luggage and other objects normally carried by pickup trucks. The present invention permits loading and unloading of heavy objects weighing over 1,000 pounds or more. The lifting device may also be mounted on a fixed platform, such as a loading dock and can be used for maritime loading and unloading of boats and ships such as fishing boats or pleasure craft. Although shown mounted on the right side of vehicle when viewed from the rear, the lifting device may be modified to allow mounting on the opposite side of the vehicle when, for example, the vehicle is driven in countries that require vehicles to drive to the left side of roads. By mounting the lifting device on the proper side of the vehicle, loading and unloading of loads next to roads may be accomplished while avoiding any traffic in adjacent lanes of travel.
While particular embodiments of the present invention have been illustrated and described, it is not intended to limit the invention, except as defined by the following claims.
