CROSS REFERENCE TO RELATED APPLICATIONS
 This application is a continuation-in-part application related to U.S. nonprovisional patent application Ser. No. 10/856,731 filed on May 27, 2004, from which all applicable priority is claimed, and which is hereby incorporated herein by reference.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH
 Not Applicable.
BACKGROUND OF THE INVENTION
 The trucking industry requires drivers of over-the-road truck and semi-trailer combinations to drive their vehicles for extended periods of time on the roads. This generates a significant problem for the truck driver when the driver needs to get some sleep to ensure that the driver is driveling safely and that the driver is conforming to the rules and laws of the trucking industry that require minimum rest periods interspersed between maximum amounts of actual driving time. As a result, truck drivers are sometimes hard-pressed to find a comfortable and convenient location where the driver can lay down to sleep. Similar problems occur when recreational vehicles are not positioned on level surfaces thereby causing the mattresses in the recreational vehicle to not be level.
 The truck manufacturing industry has attempted to remedy this problem by adding sleeping cabins to the back of the cabs of the trucks. The drivers use those sleeping cabins as temporary beds when the time to sleep and rest is dictated by the driver's fatigue or by federal laws.
 While this a significant improvement and does provide some form of rest area for the driver, it is a rare occurrence when the truck driver can find a perfectly level area in which to park the truck during the truck driver's sleeping period. Normally, the truck is parked on a surface that is not level, and is sometimes extremely out of level. Because the sleeping cabins are geometrically related to the wheels of the truck, when the truck is not level, the mattress in the sleeping cabins is also not level. In fact, the degree of levelness of the tractor is usually the same degree of levelness of the mattress in the sleeping cabins. The end result is that the truck driver is forced to try to sleep on a mattress that is out of level--sometimes severely out of level--thus inhibiting the truck driver from obtaining a good rest period. It is also noted that this undesirable condition can also occur in travel trailers and recreational vehicles.
 It is noted that there are wide variety of mattress frames that exist in the prior art to fulfill a number of different applications for mattresses. For example, mattress frames that are foldable to allow adjustment and configuration of the mattress to match the particular needs of the user are widely known in the art. Those devices allow the mattress to be formed into L-shapes, Z shapes, or U shapes depending upon the needs of the particular user. However, these prior art mattress frame devices are intended for use in non-mobile applications such as hospitals, rehabilitation centers, and personal residences and are not generally applicable to any type of highly mobile use. In particular, the prior art devices are not specifically made to be used in general automotive applications. Thus, while these bedding systems may be suitable for the purposes for which they were designed, they would not be suitable to fulfill the needs of a truck driver or a recreational vehicle owner attempting to obtain some rest on a mattress that is not level.
SUMMARY OF THE INVENTION
 In accordance with the present invention, a unique type of mattress leveling device is disclosed, and more specifically, a mattress leveling device that can be used to level the mattresses in a vehicle in which the vehicle is not residing on level ground. More specifically, the present invention is a mattress leveling device comprising a rigid frame substantially the same size as a mattress wherein the rigid frame includes lifting devices capable of individual operation that can be raised or lowered as needed to level the top of the rigid frame such that the mattress residing on the top of the rigid frame is also level thereby allowing a user to rest comfortably on the mattress without any tendency to roll off the mattress because the mattress might otherwise be out of level.
DESCRIPTION OF THE DRAWINGS
 In the accompanying drawings which form part of the specification:
 FIG. 1 is a top perspective view of one embodiment of the present invention;
 FIG. 2 is a top perspective view of the rigid frame of one embodiment of the present invention;
 FIG. 3 is a partial section view showing a splicing arrangement for the rigid frame as used in one embodiment of the present invention;
 FIG. 4 is a perspective view showing a carrying bag that can be used to transport and store one embodiment of the present invention;
 FIG. 5 is a perspective bottom view of the rigid frame of one embodiment of the present invention; and
 FIG. 6 is an exploded perspective view of the attachment of one type of lifting device used in one embodiment of the present invention.
 Corresponding reference numerals indicate corresponding steps or parts throughout the several figures of the drawings.
 While one or more embodiments of the present invention are illustrated in the above referenced drawings and in the following description, it is understood that the embodiments shown are merely examples of at least one preferred embodiment and are offered for illustration only. It is further understood that various changes in construction may be resorted to in the course of manufacture in order that the present invention may be utilized to the best advantage according to circumstances which may arise, without in any way departing from the spirit and intention of the present invention, which is to be limited only in accordance with the claims contained herein.
DETAILED DESCRIPTION OF AT LEAST ONE EMBODIMENT OF THE INVENTION
 Referring now to FIGS. 1, 2 & 3, one embodiment of the present invention is shown. More specifically, the mattress leveling device A is comprised of a rigid frame 2, a plurality of lifting devices 3, and a lifting device communication and control system 6. When in general use, a mattress 1 rests upon the mattress leveling device A.
 In this embodiment, the rigid frame 2 comprises two transverse members 7, three longitudinal members 8, a plurality of intermediate cross members 6, a plurality of end cross members 11, and a plurality of lifting device mounting plates 13. The two transverse members 7 and the three longitudinal members 8 of the present embodiment are made from substantially square tubes made using material that is about 14 gauge and that is about 1 inch square. The plurality of intermediate cross members 6 are made from bar stock material that is about 3 inches wide and about 1/8 inch thick. The plurality of end cross members 11 are made from bar stock material that is about 2 inches wide and about 1/8 inch thick. While this material is used in the present embodiment of the mattress leveling device A, it is understood that in alternative embodiments of the present invention, other materials may also be used while still remaining within the intended scope of the present invention. For example, in other embodiments, the two transverse members 7 and the three longitudinal members 8 can be made of other structural shapes such as angles, channels, and z-shaped material. In fact, any type of material and any shape of material may used as long as the type and shape of material selected is sufficiently strong and durable enough to support a person resting upon the mattress 1 that is placed upon the rigid frame 2 as the rigid frame is further supported by the mattress supporting structure of a sleeping cabin found in a common over-the-road truck or similar vehicle.
 Although the rigid frame 2 of one embodiment of the mattress leveling device A can be made in a single one-piece unit, in an alternative embodiment of the present invention, the rigid frame 2 can be of two or more pieces to more readily allow the rigid frame to be installed within the sleeping cabin of the user's truck. In such an embodiment, the rigid frame 2 (FIG. 3) comprises a first end 2A and a second end 2B that can be assembled together by installing a plurality of splice plates 9 to each side of the three longitudinal members 8 using a plurality of mounting hardware 10. In yet other embodiments, the rigid frame 2 is manufactured such that it is made of individual pieces that can be assembled within the sleeping area of the truck or recreational vehicle. In such an embodiment, the three longitudinal members 8 can be made in the form of a one piece single or multiple piece element and all other components of the mattress leveling device A are assembled on site.
 In the present embodiment, the rigid frame 2 is about 69 inches in length and 32 inches in width. When the plurality of lifting devices 3 are fully lowered, the height of the mattress leveling device is about 11/4 inch. When the plurality of lifting devices 3 are fully raised, the height of the mattress leveling device is about 7 inches. It will be appreciated that the length and the width of the rigid frame 2, and the height of the mattress leveling device A can be adjusted to fit a specific application and still remain within the scope of the present invention. It will also be appreciated that in other embodiments, the components of the mattress leveling device A can be made slideably adjustable, incrementally adjustable, or generally adjustable using other methods such that the mattress leveling device can be assembled or installed in various locations of different dimensions or to fit the size of the mattress 1 that will rest upon the mattress leveling device. The designs, configurations, and methods of making the components of the present invention adjustable are well-known in the industry and can be readily adapted to the present invention.
 Each of the plurality of lifting devices 3 can be of any general design, however, in a preferred embodiment, each of the plurality of lifting devices is a fluid chamber that can be pressurized and depressurized to accomplish the raising or the lowering of the corners of the rigid frame 2. Those of skill in the art will appreciate that while the embodiments herein disclose the use of fluid chambers that can be pressurized and depressurized to raise and lower portions of the rigid frame 2, yet other embodiments may utilize mechanical lifting devices 3 such as lever actuated or gear driven devices driven by electric motors. Thus, it is understood that the lifting device 3 can be any lifting element as long as the lifting element selected is capable of sufficiently lifting the mattress leveler A.
 In one variation of the preferred embodiment in which fluid chambers are used, the fluid chamber 3 comprises two inner tubes that are substantially assembled together with their longitudinal axes aligned. In that embodiment, each of the inner tubes is 4.10/3.50-4 in size. It is appreciated that while the two inner tubes of each of the plurality of fluid chambers 3 is assembled together, that when assembled there are a plurality of openings remaining that can be used to feed mounting devices such as elastic cords between the two assembled inner tubes. These mounting devices are then attached to some mounting portion of the rigid frame 2 to substantially dispose the plurality of fluid chambers 3 on the rigid frame.
 In alternative embodiments, the plurality of fluid chambers 3 are designed to be mounted to the rigid frame 2 by other means including, for example, threaded fasteners and/or mounting brackets that may used to mount and retain the plurality of fluid chambers in position in relation to the rigid frame 2. In fact, the plurality of lifting devices 3, whether in the embodiment utilizing fluid chambers or other lifting devices, may be mounted to the rigid frame 2 in any manner as long that mounting configuration used results in the mounting of the plurality of lifting devices to the rigid frame 2 in a manner that allows the lifting device to operate as described herein.
 The lifting device communication and control system 4 comprises all elements necessary to individually control the plurality of lifting devices 3. For example, if the lifting devices 3 include electric motor activated devices, the lifting device communication and control system 4 would include electrical conductors and switches to individually and effectively communicate with each lifting device 3. In the case of lifting devices 3 that comprise fluid chambers, the lifting device communication and control system 4 would include all necessary fluid conductors and fluid control valves needed to individually and effectively communicate each lifting device 3.
 In one embodiment as disclosed herein, the lifting device communication and control system 4 (FIG. 1) includes a number of fluid control components that allow the plurality of fluid chambers 3 to be individually inflated or deflated as needed to level the rigid frame 2 as necessary to achieve a level mattress 1 when a mattress is residing on the rigid frame. In the present embodiment, the lifting device communication and control system 4 utilizes compressed air as the fluid. The compress air is directed and controlled within the lifting device communication and control system 4 by a plurality of fluid conductors 4B and a plurality of fluid control switches 5.
 More specifically, the fluid conductors 4B comprise a series of air lines that have an inside diameter of about 1/4 inch. The plurality of fluid conductors 4B are routed as necessary to obtain allow the mattress leveling device A to operate as disclosed below. The four fluid control switches 5 in this embodiment are air switches similar to Part #032201 as manufactured by GT Development Corporation located in the State of Washington. Each fluid control switch 5 is a paddle switch that has three positions with a spring return to a center position in which no fluid flows through the fluid control witch. When the paddle of an individual fluid control switch 5 is moved to a first position, fluid flows through the fluid control switch and the fluid conductors 4B to allow compress air to enter into a single fluid chamber 3 (FIG. 5). When the paddle of the same individual fluid control switch 5 (FIG. 1) is moved to a second position, fluid flows through the fluid control switch and the fluid conductors 4B to allow compress air to be relieved from the same single fluid chamber 3 (FIG. 5). The three fluid control switches 5 operate in a similar manner to individually inflate or deflate each of the other plurality of fluid chambers 3.
 In operation, the first end 2A (FIG. 2) of the rigid frame 2 and the second end 2B of the rigid frame 2 are placed onto the mattress area of a sleeping cabin of an over-the-road truck or a recreational vehicle such that the plurality of lifting devices 3 are disposed between the rigid frame 2 and the area of the sleeping cabin where the mattress 1 would normally resides. The first end 2A and the second end 2B of the rigid frame 2 are assembled together by installing the plurality of splice plates 9 (FIG. 3) and the plurality of mounting hardware 10 to each side of the three longitudinal members 8. The result of the assembly process is a single substantially rigid, non-foldable frame 2 (FIG. 1) upon which the mattress 1 can be placed.
 In the present embodiment, when the rigid frame 1 is assembled and in position, the user connects the fluid conductors 4B and the fluid control and communication system 4 to a pressurized air source. It is understood that in the present embodiment, the pressurized air source is the compressed air system of the truck or recreational vehicle into which the mattress leveling device A is being installed. Thus, a fluid conductor 6 can be sufficiently spliced into the truck's or recreational vehicle's pressurized air system such that a sufficient volume of air at a sufficient air pressure can be introduced and used within the fluid control and communication system 4. It will be appreciated that in other alternative embodiments of the present invention, other sources of pressurized fluid can be used and still remain within the intended scope of the present invention. For example, a stand alone air compressor (not shown) can also be used to introduce pressurized fluid into the fluid control and communication system 4. The stand alone air compressor could be operated using electricity obtained from the truck's onboard electrical systems.
 It is also understood that in other embodiments where the lifting devices 3 (FIG. 5) are not fluid chambers, but are instead electromechanical devices, once the rigid frame 2 is installed as indicated above, the mattress leveling device A can be connected to a power source capable of providing the electrical power necessary to operate the electromechanical lifting devices 3. In such electromechanical embodiments, the electrical power source can be the truck's or the recreational vehicle's onboard electrical system. In other embodiments, the power source can be an electrical system other than the truck's or recreational vehicle's onboard electrical system. For example, the electrical power may be supplied by an alternative power source such as a battery (not shown), or where standard AC power is available, the mattress leveling device A may also be connected to a standard 120V AC power source (not shown). Regardless of the type of lifting device 3 utilized or the type of power used, it is understood that each of those embodiments are within the general scope of some embodiments of the present invention.
 In the present fluid chamber embodiment, after the rigid frame 2 (FIGS. 1 & 3) has been assembled and the mattress 1 placed upon the rigid frame, the user determines how level the mattress is as it resides upon the top surface of the rigid frame. If the mattress 1 is not level, the user then utilizes the fluid control switches 5 to inflate or deflate one or more of the plurality of fluid chambers 3 until the mattress is leveled to the satisfaction of the user. For example, if the user facing the installed mattress leveling device A believes the mattress 1 residing on the mattress leveling device is tilted downward toward the user and downward to the user's left, the user can use the single switch 5 to inflate the fluid chamber 3 that is nearest the user and to the user's left until the mattress 1 has been sufficiently leveled. Then the user can manipulate the other fluid control switches 5 as necessary to inflate the fluid chamber 3 that is to the user's left and furthest away from the user, and the fluid chamber that is to the user's right and closest to the user until the inflation of those two fluid chambers results in the stabilization of the rigid frame 2 and mattress 1 sufficient to make the mattress 1 level while not allowing the mattress to rock. Thus, when completed, this process results in a mattress 1 that is substantially level and substantially stable enough to. allow the user to rest upon the mattress without substantial discomfort that can result from attempting to sleep on a mattress that is not level and that is not stable.
 In other embodiments of the present invention, the raising or lowering of the lifting devices can be accomplished in specific groupings. For example, one grouping may be the two front lifting devices nearest the user. That specific grouping may be controlled by a single switch that can be used to raise or lower those two lifting devices 3 as a group. It is understood that other such groupings are also possible.
 When the mattress leveling device must be transported or stored, the components of the mattress lifting device may be stored in a storage bag 15 (FIG. 4).
 While the above description describes various embodiments of the present invention, it will be clear that the present invention may be otherwise easily adapted to fit any configuration where a mattress leveling device is required. Additionally, as various changes could be made in the above constructions without departing from the scope of the invention, it is also intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. The scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given.