Not Applicable
Not Applicable
1. Field of the Invention
This invention relates generally to suspensions of trailers, and more particularly to a suspension system for a trailer that has a bed that can be lowered to the ground.
2. Description of Related Art
Utility trailers are commonly coupled behind self-propelled vehicles and used to haul bulky and/or heavy objects. A typical trailer includes a frame supported on wheels and a platform called a “bed” on which a load is placed. Some trailers include ramps for loading and unloading cargo. Other trailers are designed to be tipped to facilitate loading and unloading.
Trailers are also known that have beds that can be lowered to the ground. An example of such a trailer is disclosed in Stringer, U.S. Pat. No. 6,273,435, which teaches a trailer that includes a bed that is attached to the frame with a hydraulic slider that functions to raise and lower the bed.
Behr, U.S. Pat. No. 5,536,131, teaches a utility trailer that includes a bed that is pivotally attached to a frame of the trailer. A hand winch is used to manually raise and lower the bed in a generally vertical direction.
Shiels, U.S. Pat. No. 4,673,328, teaches a trailer with a lift/tilt-bed. The trailer includes four pivotal tracks that function to guide the bed from the lowered to the raised position.
Various other prior art references teach similar trailers, including Bartel, U.S. Pat. No. 6,142,496, Wellman, U.S. Pat. No. 5,810,544, Nowell et al., U.S. Pat. No. 5,765,859, Rogge et al., U.S. Pat. No. 5,474,416, Celli, U.S. Pat. No. 4,685,855, and Fowler, U.S. Pat. No. 4,154,352.
The above-described patents are hereby incorporated by reference in full.
In many wheeled vehicles, each wheel is suspended via a suspension system that dampens roughness of a surface under the wheel as the wheel moves over the surface. In general, a trailer is a vehicle adapted to be pulled (i.e., towed) behind a self-propelled vehicle. Known suspension systems for trailers include spring-mounted axles. In a typical trailer with a spring-mounted axle, the axle extends between opposite sides of the trailer and passes under a bed of the trailer. Located under the bed, the axle prevents the bed from being lowered to the ground.
It would be beneficial to have a suspension system for a wheel of a vehicle that does not extend under the vehicle. Such a suspension system would allow, for example, the construction of a trailer having a bed that can be lowered to the ground to facilitate loading objects on the bed and unloading objects from the bed.
A suspension system for a wheel is disclosed including an elongate post member, a wheel mount adapted for mounting the wheel, an axle for rotatably mounting the wheel mount on the elongate post member, a frame adapted to slidably receive the post member such that the post member slides between a first position and a second position, and a resilient member adapted to bias the post member toward the first position. A vehicle is described including the suspension system.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.
The accompanying drawings illustrate the present invention. In such drawings:
The wheel 16A is coupled to the frame arm 20A via the suspension system 110A, and the wheel 16B is coupled to the frame arm 20B via the suspension system 110B. As described in more detail below, the suspensions systems 110A and 110B advantageously include stub axles such that an area under the bed 24 is free from any component of the trailer 10. This advantageously allows the bed 24 to be lowered to the surface 14.
It is noted that the suspension systems 110A and 110B may be used to couple wheels to frames of other types of vehicles. That is, the trailer 10 of
In the embodiment of
The post member 114 has an axle 116 extending outwardly from one side, and a spring mount 128 also extending outwardly, in this embodiment from an opposite side. The axle 116 rotatably mounts the wheel hub 118 on the post member 114. The wheel hub 118 has lug bolts or similar features extending outwardly for mounting the wheel 16B.
The post member 114 is shown in a first (i.e., lowered) position within the frame 112 of the suspension system 10B. In general, the spring 120 or resilient member is adapted to bias the post member 114 toward the first position. The spring 120 is coupled to an upper end of the post member 114 and opposes upward movement of the post member 114 within the frame 112. In
While one embodiment of the spring is shown, those skilled in the art will recognize that many different forms of spring or resilient member could be adapted to the present suspension system 110B, and such alternatives should be considered within the scope of the term “resilient member” or “spring” as used in the presently claimed invention.
The frame 112 may include at least one bearing member positioned within the frame 112 to is slidably receive the post member 114. In the embodiment of
In the embodiment of
When the left wheel 16B of the trailer 10 is mounted to the wheel hub 118, a left side of the frame 12 of the trailer 10 is supported above the surface 14 (
Many other superficial changes can be made to the suspension system 110B by those skilled in the art without altering the fundamental design of the present invention. For example, the springs 120 could be inverted, the frame 112 could be attached in a different manner, and many other changes. Such alterations should be considered within the scope of the present invention.
While the invention has been described with reference to at least one preferred embodiment, it is to be clearly understood by those skilled in the art that the invention is not limited thereto. Rather, the scope of the invention is to be interpreted only in conjunction with the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
879160 | Fulton | Feb 1908 | A |
2310821 | Wimbish | Feb 1943 | A |
2831699 | Holmes | Apr 1958 | A |
2888268 | Fellabaum | May 1959 | A |
3621739 | Seablom | Nov 1971 | A |
3927900 | Wischmeier | Dec 1975 | A |
4077643 | Bates | Mar 1978 | A |
4154352 | Fowler | May 1979 | A |
4673328 | Shiels | Jun 1987 | A |
4685855 | Celli | Aug 1987 | A |
4789181 | Baxter | Dec 1988 | A |
5474416 | Rogge et al. | Dec 1995 | A |
5536131 | Behr | Jul 1996 | A |
5765859 | Nowell et al. | Jun 1998 | A |
5810544 | Wellman | Sep 1998 | A |
6142496 | Bartel | Nov 2000 | A |
6273435 | Stringer | Aug 2001 | B1 |