BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an isometric view of a sliding and folding staircase, according to a first embodiment of the present invention, shown in separated form;
FIG. 1A is an isometric view of the sliding and folding staircase, according to a second embodiment of the present invention, shown in separated form;
FIG. 2 is a side view of the staircase, according to a first embodiment, shown in its stored position, together with a breakaway view of a vehicle to which the staircase is attached;
FIG. 2A is a side view of the staircase, according to a second embodiment, shown in its stored position, together with a breakaway view of a vehicle to which the staircase is attached;
FIG. 3 is a side view of the staircase, according to the first embodiment, shown extended but folded, together with a breakaway view of a vehicle to which the staircase is attached;
FIG. 3A is a side view of the staircase, according to the second embodiment, shown extended but folded, together with a breakaway view of a vehicle to which the staircase is attached;
FIG. 4 is a side view of the staircase, according to the first embodiment, shown in its use position;
FIG. 4A is a side view of the staircase, according to the second embodiment, shown in its use position;
FIG. 5 is an exploded view of a stairhead and its support track, according to the first embodiment;
FIG. 5A is an exploded view of the stairhead and its support track, according to the second embodiment;
FIG. 6 is a breakaway view of a vertical stairhead support beam and foot, shown in partial section and as seen along line 6-6 of FIG. 2 and FIG. 2A;
FIG. 7 is a cross-sectional view taken along line 7-7 of FIG. 2 and FIG. 2A;
FIG. 8 is a fragmentary view of a stairhead locking mechanism as seen along line 8-8 of FIG. 2 and FIG. 2A;
FIG. 9A is an isometric view of the sliding and folding staircase, according to the second embodiment of the present invention, shown in the first of three use positions;
FIG. 9B is an isometric view of the sliding and folding staircase, according to the second embodiment of the present invention, shown in the second of three use positions;
FIG. 9C is an isometric view of the sliding and folding staircase, according to the second embodiment of the present invention, shown in the third of three use positions;
FIG. 10 is an exploded view of the staircase, stairhead and its support track, according to the second embodiment of the present invention;
FIG. 11 is an exploded view of a stairhead and its support track, according to the second embodiment of the present invention, shown in the second of three use positions; and
FIG. 12 is an exploded view of a stairhead and its support track, according to the second embodiment of the present invention, shown in the third of three use positions.
DETAILED DESCRIPTION OF INVENTION
The preferred embodiment of the invention herein described relates to an improvement to the folding steps of U.S. Pat. No. 5,397,143, the content of which is herein incorporated by reference. As the folding steps of this invention are of like construction to the referenced patent, the numbering systems of the two inventions will correspond, and a detailed description as to the folding step portion of the present invention will not be repeated.
The staircase 2 includes a plurality of steps 4 as illustrated in FIGS. 1 and 4 with each step being pivotally secured at opposite sides to a pair of side rails 6. The uppermost step 4a is hingedly connected to a step bracket 10 that is bolted to a stairhead 80 and stairhead vertical supports 60. Side rails 6 at each side of the staircase are generally parallel with each other and extend beyond the lowermost step 4b. A pod 14 in the form of an L-shaped bracket is mounted to the lower end of each side rail 6 and fastened by bolts 16.
A pair of guide rods 20 are attached between the vehicle 18 and staircase 2. Each guide rod extends freely through a sleeve 24 and has a threaded lower end upon which a nut 26 is turned. A yoke 28 is fastened to the upper end of each guide rod 20. Each yoke 28 is fastened by a connector through a hole 50 in a bracket 32 that is connected to a stairhead vertical support 60. In one embodiment, a handrail 34 extends along each side of the steps 4. Each handrail 34 is pivotally secured at one end to a bracket 38 connected to the stairhead vertical support 60. An outset retainer bracket 37 is preferably welded at one end to each of the side rails 6 at their outer sides. A leg 30 is pivotally secured to a bracket 36 preferably welded to each handrail 34 at its opposite end. Each leg 30 is inserted between a retainer bracket 37 and its connected side rail 6 to prevent lateral movement relative to the transverse axis of the handrail 34. A lock pin 48 with an attached clasp 43 is inserted through hole 41 in bracket 32.
A pair of stairhead handrails 74 are attached between the vehicle exterior wall 18 and the stairhead vertical support 60. Each stairhead handrail 74 is pivotally secured at one end to a bracket 72 attached to the vehicle 18. A chain 68 is preferably extended between bracket 32 connected to the stairhead vertical support 60 and bracket 70 attached to the vehicle 18. Bracket 76 is attached to the vehicle 18 and secures each stairhead handrail 74 when staircase 2 is not in use. When in use, the yoke 78 of stairhead handrail 74 is fastened to the stairhead vertical support 60 through bracket 62.
Before operation, the staircase 2 is shown in its folded position in FIGS. 1, 2 and 3 for storage. Each handrail 34, leg 30, side rail 6, and guide rod 20 are pivotally moved upward relative to the vehicle 18 and are preferably secured by lock pin 48 against the side of the vehicle 18. The lock pin 48 is inserted through aligned holes 41 formed in the side rails 6 and bracket 32. Safety catch 43 is preferably swung over the lock pin 48 to prevent removal of the lock pin 48.
In FIG. 2, the stairhead 80 and its horizontal supports 84 are shown with the staircase 2 in its locked folded storage position next to the vehicle 18. In FIG. 3, the stairhead 80 is extended away from the vehicle 18 along a support track 90 attached to the underside or chassis of the vehicle 18. A series of wheels 86 within the stairhead horizontal supports 84 allow for ease of extension of the stairhead 80. As shown in FIG. 5, support track wheels 88 preferably attached to support track 90 help to stabilize stairhead 80 during extension and aid in ease of extension, as well. In FIG. 7, the support track wheel 86 is shown in operation within support track 90. Locking mechanisms 92 secure stairhead 80 to the vehicle 18 preferably by way of bracket 96 attached to vehicle 18, as shown in detail in FIG. 8. To extend stairhead 80, pins 94 are released from holes 81 in outer horizontal stairhead supports 84. Stairhead 80 and stairhead supports 84 are pulled along support track 90 (see FIG. 3) until pins 94 of locking mechanisms 92 align with holes 83 in the outer horizontal stairhead supports 84. Pins 94 are inserted into holes 83 and the stairhead 80 is locked in its extended position. The staircase 2 is then lowered (see FIG. 4).
In operation, the staircase 2 and stairhead 80 are extended away from the vehicle 18, with the staircase 2 in its upper storage position, as shown in FIGS. 1 and 3. The staircase 2 is then lowered to its downward use position, as shown in FIG. 4. Each sleeve 24 abuts a nut 26 on guide rod 20 and is preferably welded at its lower end to a bracket 27 which is pivotally connected to the uppermost step 4a. The yoke 28 is then connected to bracket 32 through hole 50 to secure guide rod 20. The guide rods 20, in conjunction with the sleeves 24, stabilize the staircase 2 if the pod 14 rest upon uneven ground 52. Stairhead handrails 74 are pivoted in bracket 72 to connect yoke 78 to bracket 62, which is preferably welded to stairhead vertical support 60. The chain 68 is extended between bracket 70 and bracket 32 for safety.
For support, stairhead vertical feet 64 are extended downward to meet the ground 52 by release of each locking mechanism 66. As shown in FIG. 6, each locking mechanism 66 is threaded through hole 67 in the stairhead vertical support 60 and secured against stairhead vertical foot 64. For release, each locking mechanism 66 is unscrewed enough to allow stairhead vertical foot 64 to extend to a desired position where ground contact is made. Each locking mechanism 66 is then re-threaded to abut each stairhead vertical foot 64.
A second embodiment of the sliding and folding steps is shown in FIGS. 1A, 2A, 3A, 4A, 5A, 9A, 9B, 9C, 10, 11 and 12. As desired, in the second embodiment, the staircase 2 may be moved to any one of three positions: front-facing, as shown in FIGS. 9A and 10; right-side-facing, as shown in FIGS. 9B and 11; and left-side-facing, as shown in FIGS. 9C and 12.
As shown in FIG. 5A, a moveable vertical support frame member 100 has first and second tubular stanchions, 100a and 100b that are attached to step bracket 110 and slid telescopically over vertical inner supports 120a and 120b. The step bracket is pivotally connected to the staircase 2. Moveable vertical support frame members 160 are removably secured in holes 102a and 102b. A moveable vertical inner support 160a, shown in FIGS. 11 and 12, having outside dimensions less than that of vertical support frame members 160, is used when the staircase 2 is moved to one of two side-facing positions in the second embodiment.
When used, staircase 2 and stairhead 80 are extended away from the vehicle 18, with the staircase 2 in its upper storage position, as shown in FIGS. 1A and 3A. Utilizing a forward-facing position for the staircase 2, as shown in FIGS. 4A and 9A, the staircase 2 is lowered to its downward use position. Each sleeve 24 abuts a nut 26 on guide rod 20 and is preferably welded at its lower end to a bracket 27 which is pivotally connected to the uppermost step 4a. The yoke 28 is then connected to bracket 32 through hole 50 to secure guide rod 20. The guide rods 20, in conjunction with the sleeves 24, stabilize the staircase 2 if the pod 14 rest upon uneven ground 52. Stairhead handrails 174 are then connected to bracket 172 on one end and bracket 162, which is preferably welded to tubular stanchions 100a and 100b, on the other end. A second handrail 168 is extended between bracket 170, which is preferably welded to tubular stanchions 100a and 100b, and bracket 132 for safety.
To move the staircase 2 to a one of two side-facing positions, as shown in FIGS. 9B and 9C, moveable vertical support frame member 160 and moveable vertical inner support 160a are each removably secured in one of the holes 102a or 102b, while moveable vertical support frame member 100, with tubular stanchions 100a and 100b, and another moveable tubular stanchion 140, are slid over vertical inner supports 120a, 120b, and 160a.
In a right-side-facing staircase 2 position, as shown in FIGS. 9B and 11, movable vertical inner support 160a is secured in hole 102b. Moveable vertical support frame member 100 with connected staircase 2 is shifted so that tubular stanchion 100a slides over vertical inner support 120b and tubular stanchion 100b slides over moveable vertical inner support 160a. Moveable vertical support frame member 160 is secured in hole 102a and moveable tubular stanchion 140 is secured over vertical inner support 120a.
In a left-side-facing staircase 2 position, as shown in FIGS. 9C and 12, movable vertical inner support 160a is secured in hole 102a. Moveable vertical support frame member 100 with connected staircase 2 is shifted so that tubular stanchion 100a slides over moveable vertical inner support 160a and tubular stanchion 100b slides over vertical inner support 120a. Moveable vertical support frame member 160 is secured in hole 102b and moveable tubular stanchion 140 is secured over vertical inner support 120b.
In both the right-side- and left-side-facing positions, lower handrails 174 are connected between brackets 170 and brackets 132, and upper handrails 168 are connected between brackets 172 and 162.
The embodiments herein described is not intended to be exhaustive nor limiting in the precise form of the invention disclosed. They are chosen and described to explain the principles of the invention and its application and practical use so that others skilled in the art may follow their teachings.
Patent Application
20080022611
