Trailer stacking device

1 . A trailer stacking device for lifting and stacking trailers comprised of:

two masts;

two support frames;

two trailer supports;

wherein one of the masts is rigidly affixed to the ground;

wherein the other mast is not rigidly affixed to the ground;

wherein each of the support frames is moveably attached to a respective mast;

wherein each of the trailer supports is attached to a respective support frame;

wherein each of the support frames may be selectively vertically raised or vertically lowered in relation to the mast to which the support frame is moveably attached.

2 . The trailer stacking device of claim 1 further comprising:

guide rails rigidly affixed to the ground;

wherein the guide rails are used for positioning trailers to be stacked.

3 . The trailer stacking device of claim 1 wherein the mast that is not rigidly affixed to the ground is a moveable mast that includes means for movement to a desired location such that the moveable mast may be positioned at a desired distance apart from the mast that is rigidly affixed to the ground in order to accommodate various lengths of trailers to be stacked.

4 . The trailer stacking device of claim 3 further comprising:

mast tracks that are rigidly affixed to the ground, wherein the at least one moveable mast is moveably connected to the mast tracks and may be moved to a desired location along the length of the mast tracks.

5 . The trailer stacking device of claim 4 further comprising:

guide rails rigidly affixed to the ground, wherein the guide rails are used for positioning trailers to be stacked in relation to the location of one or more masts.

6 . The trailer stacking device of claim 1 further comprising:

first actuation means for moving the support frame of each mast in a vertical direction in relation to the mast to which the support frame is moveably attached such that the first actuation means allows for the support frame to be vertically raised or vertically lowered to a desired location;

second actuation means for moving the support frame of each mast in a first horizontal direction that is orthogonal to the vertical direction such that the support frames may be selectively horizontally shifted in relation to its respective mast by such second actuation means;

third actuation means for moving the trailer support attached to each support frame in a second horizontal direction that is orthogonal to the first horizontal direction such that the trailer supports may be selectively extended away from their respective support frames or retracted towards their respective support frames by such third actuation means.

7 . The trailer stacking device of claim 6 further comprising:

means for floating movement of the trailer supports in response to sudden forward movement of a trailer that is in contact with the trailer supports.

8 . A trailer stacking device for lifting and stacking trailers comprised of:

four masts;

wherein two of the masts are rigidly affixed to the ground;

wherein the other two masts are not rigidly affixed to the ground;

four support frames;

four trailer supports;

wherein each of the support frames is moveably attached to a respective mast;

wherein each of the trailer supports is moveably attached to a respective support frame;

wherein each of the support frames may be selectively vertically raised or vertically lowered in relation to the mast to which the support frame is moveably attached.

9 . The trailer stacking device of claim 8 further comprising:

guide rails rigidly affixed to the ground;

wherein the guide rails are used for positioning trailers to be stacked.

10 . The trailer stacking device of claim 8 wherein the two masts that are rigidly affixed to the ground are stationary masts that cannot be moved during operation of the trailer stacking device, and the two masts not rigidly affixed to the ground are moveable masts that include means for movement to a desired location such that the moveable masts may be positioned at a desired distance apart from the stationary masts that are rigidly affixed to the ground in order to accommodate various lengths of trailers to be stacked.

11 . The trailer stacking device of claim 10 further comprising:

two sets of mast tracks that are rigidly affixed to the ground, wherein the moveable masts are each moveably connected to one of the sets of mast tracks and may be moved to desired locations along the length of their respective mast tracks.

12 . The trailer stacking device of claim 11 further comprising:

guide rails rigidly affixed to the ground, wherein the guide rails are used for positioning trailers to be stacked in relation to the location of the masts.

13 . The trailer stacking device of claim 8 further comprising:

first actuation means for moving the support frame of each mast in a vertical direction in relation to the mast to which the support frame is moveably attached such that the first actuation means allows for the support frame to be vertically raised or vertically lowered to a desired location;

second actuation means for moving the support frame of each mast in a first horizontal direction that is orthogonal to the vertical direction such that each support frames may be selectively horizontally shifted in relation to the respective mast to which the support frame is moveably attached by such second actuation means;

third actuation means for moving the trailer support attached to each support frame in a second horizontal direction that is orthogonal to the first horizontal direction such that the trailer supports may be selectively extended away from their respective support frames or retracted towards their respective support frames by such third actuation means.

14 . The trailer stacking device of claim 13 further comprising:

means for floating movement of the trailer supports in response to sudden forward movement of a trailer that is in contact with the trailer supports.