CA2859432C - Foldable extension deck and ramp assembly for pickup truck - Google Patents

Abstract

The foldable truck bed extension deck and ramp assembly are mountable in a short-box pickup truck. The bed extension deck and ramp assembly have a comparable length to a full-size pickup truck box when deployed for use, and are jointly foldable to fit into a short-bed pickup truck with its tailgate closed when not used. The bed extension deck has a strong upper surface to resist deformation in rough use. The ramp member can be deployed with its front end matching the surface of the extension deck so that a vehicle can be driven along the ramp member and onto the deck surface without encountering any transition step.

Description

TITLE: FOLDABLE EXTENSION DECK AND RAMP ASSEMBLY
FOR PICKUP TRUCK
FIELD OF THE PRESENT INVENTION
The present invention pertains to the field of truck ramps stowed inside truck-bed liners, and more particularly, it pertains to foldable bed extension deck and ramp assemblies for use in short-box pickup trucks.
BACKGROUND OF THE PRESENT INVENTION
Modern pickup trucks have extended cabs capable of sitting five passengers comfortably. The boxes of these modern pickup trucks have a length of 6 ft.-6 in., basically. These short boxes cannot transport trail-type or mountain-type snowmobiles with lengths of 11 and 13 feet respectively, even with the tailgate in the open position. Similarly, lumber and other residential construction materials are sold in 8, 10 and 12 foot lengths.
Transporting these materials in a short-box pickup truck can sometimes be a challenge. For these reasons, it is believed that modern short-box pickup trucks have created a market need for truck bed extension decks that can be used to transport material and equipment that is best transported in a conventional 8-foot truck box.
Conventional ramps for use with pickup trucks have a length of 8 feet. It is generally accepted that an 8-foot ramp provides an easy slope for loading a vehicle in the truck box. Short truck boxes are inherently associated with shorter ramps and a steeper climbing angle for loading sport or gardening equipment in the truck box. This inconvenience also points to a market need for truck bed extension decks that can be used to transport material and equipment that is best transported in a conventional 8-foot truck box.
In another aspect oftruck bed liners, the most important factor in the design of a truck ramp and truck-bed liner or extension deck, is a weight-to-strength ratio of the deck itself. A truck owner does not want to carry extra weight in his truck and to spend unnecessary fuel. On the other hand, the buyer of a truck bed liner and ramp assembly wants this equipment to be strong, durable, usable and safe. In that point of view, a frame that is made of flat bars mounted on their edges offers the best weight-to-strength ratio, when compared to hollow structural tubing or structural angles of a same weight per foot for example. Despite this advantage, it is believed that a framing system made of flat bars in a truck bed liner has not been used in the past.
A number of truck-bed liners with and without ramps have been found in the prior art. It is believed that the following documents provide a good inventory of these previous inventions:
US Patent 4,573,731 issued to H. L. Knaack et al., on Mar. 4, 1986;
US Patent 4,601,632 issued to J.H. Agee on July 22, 1986;
US Patent 4,624,619 issued to M.L. Uher on Nov. 25, 1986;
US Patent 4,685,857 issued to M.N. Goeser et al., on Aug. 11, 1987;
US Patent 4,722,109 issued to E.E. Mountz on Feb. 2, 1988;
US Patent 4,733,898 issued to S.D. Williams on Mar. 29, 1988;
US Patent 4,900,217 issued to J.N. Nelson on Feb. 13, 1990;
US Patent 4,990,049 issued to J.F. Hargrove on Feb. 5, 1991;
US Patent 5,257,894 issued to H.K. Grant on Nov. 2, 1993;
US Patent 5,393,192 issued to J.C. Hall et al., on Feb. 28, 1995;
US Patent 5,468,114 issued to S.J. Hickerson on Nov. 21, 1995;
US Patent 5,533,771 issued to S. Taylor et al., on July 9, 1996;

2 US Patent 5,570,989 issued to M. Belanger on November 5, 1996;
US Patent 5,795,125 issued to C.D. Walkden on Aug. 18, 1998;
US Patent 5,863,173 issued to R.A. Bremner on Jan. 26, 1999;
US Patent 6,464,274 issued to F.L. Mink et al., on Oct. 15, 2002;
US Patent 6,484,344 issued to S.M. Cooper on Nov. 26, 2002;
US Patent 7,128,357 issued to N.C. Carroll on Oct. 31, 2006;
CA Patent 1,033,313 issued to J. L. Glassmeyer on June 20, 1978;
CA Patent 1,284,564 issued to D. Manning et al., on June 04, 1991;
CA Patent Appl. 2,076,255 published by G.O. Alexander on Feb. 18, 1994;
It is believed that a market need exists in the field of truck accessories for a foldable bed extension deck and ramp assembly having a good weight-to-strength ratio, and that can be mounted in a short-box pickup truck to provide the same advantages as those of a full size truck box, while preserving the integrity of the tailgate of the pickup truck.
SUMMARY OF THE PRESENT INVENTION
In the present invention, there is provided a foldable truck bed extension deck and ramp assembly that are mountable in a short-box pickup truck.
The bed extension deck and ramp assembly according to the present invention have a comparable length to a full-size pickup truck box when deployed for use, and are jointly foldable for storage into a short-bed pickup truck with its tailgate closed.
In a first embodiment of the present invention, the bed extension deck and ramp assembly are foldable over a right angle to fit inside a short bed pickup truck with its tailgate closed. In a second embodiment of the present invention, the bed extension deck and ramp assembly are foldable

3 over a straight angle to fit inside a short bed pickup truck with its tailgate closed, and so as to be completely concealed from view inside the truck box, such as under a tonneau cover for example, when not in use.
The bed extension deck and ramp member assembly also have other features that are advantageous to pickup truck owners. The bed extension deck has a strong upper surface to resist deformation in rough use. The ramp member can be deployed with its front end matching the height of the surface of extension deck so that a vehicle can be driven along the ramp member and onto the deck surface without encountering any transition step.
More specifically, in a first aspect of the present invention, there is provided a truck bed extension deck and a ramp member that is telescopically mounted inside the bed extension deck. The bed extension deck has a channel on each side thereof The ramp member has two sides, a front end and a dolly mounted on each side, near the front end. Each of the dollies has a pair of closely spaced casters mounted thereon. Each of these dollies are guided for movement along a lower flange of one of the channels inside the bed extension deck. Each dolly also has an arm extending backward from the pair of casters. Each arm is pivoted to a respective side of the ramp member at a distance from the front end of the ramp member.
Each channel has a guide block mounted to a web thereof at a distance from the lower flange at the rear end thereof. At the rear end of its travel, each dolly is movable to precisely fit between the guide block and the lower flange of the channel. In this position, each dolly is held firmly between the guide block and the lower flange of the channel when upward or downward forces are applied to the arms of the dolly.

4 Because the ramp member is pivoted to the arms of the dollies, at a distance from the front end thereof, the front end of the ramp member, in use, extends higher than the dollies to match the level of the floor surface on the bed extension deck. Equipment may be rolled onto the ramp member and deck surface without encountering a transition step at the rear edge of the bed extension deck.
In a second aspect of the present invention, there is provided a truck bed extension deck and a ramp member telescopically mounted inside the bed extension deck. The bed extension deck has a top plate; a channel on each side thereof and a structural frame system extending between the channels and the top plate.
The structural frame system comprises transverse flat bars extending across the channels and longitudinal flat bars extending across the transverse flat bars. The structural frame system also comprises angle joiners and fasteners retaining each end of one of the longitudinal flat bars to one of the transverse flat bars; and angle clips affixed exclusively to the longitudinal flat bars and the top plate for retaining the top plate to the structural frame.
The transverse flat bars are held against canting by the longitudinal flat bars. A deformation or sagging in the top plate is not transmitted to the transverse flat bars, and does not reduce the tensile strength of these transverse flat bars.
In a third aspect of the present invention, there is provided a truck bed extension deck having a ramp member telescopically mounted inside the bed extension deck. The bed extension deck has a front segment and a rear segment. The rear segment is joined to the front segment by a first hinge

5 such that the rear segment is foldable upwardly relative to the front segment.
Similarly, the ramp member has a front portion and a rear portion. The rear portion is joined to the front portion by a second hinge such that the rear portion is foldable upwardly relative to the front portion.
The ramp member also has a pair of lock bars movably mounted thereto, extending in the ramp end section and in the end of the ramp member, such as dead bolts, for preventing a folding movement of the ramp end section relative to the ramp member.
In yet another characteristic, a bar locking mechanism including a handle are included on the ramp end section for locking a position of the lock bars when the ramp assembly is in use.
This brief summary has been provided so that the nature of the invention may be understood quickly. A more complete understanding of the invention can be obtained by reference to the following detailed description of the preferred embodiments thereof in connection with the attached drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation side view of a modern short-box pickup truck, with the first preferred bed extension deck installed and stowed therein;
FIG. 2 is a cross-section side view of the short box of the pickup truck shown in FIG. 1, with the first preferred bed extension deck and ramp

6 assembly mounted in the truck box in a deployed mode;
FIG. 3 is an enlarged side view of a segment along the ramp member in the first preferred bed extension deck and ramp assembly, showing a latch along the ramp member;
FIG. 4 is an end view of the ramp member;
FIG. 5 is a perspective top and rear view of the first preferred bed extension deck and a cut-away view through the cover plate of the first preferred extension deck, showing the framing arrangement inside the extension deck;
FIG. 6 is an enlarged side view of the framing arrangement inside the first preferred extension deck, as seen in detail circle 6 in FIG. 5;
FIG. 7 is a cross-section side view through the first preferred extension deck illustrating the position of the ramp member relative to its dolly and pivot assembly when the ramp member is deployed for use;
FIG. 8 is a side view through the bed extension deck illustrating the ramp member in a horizontal alignment ready to be stowed inside the first preferred bed extension deck;
FIG. 9 is an enlarged cross-section side view of a short box of a pickup truck with the first preferred bed extension deck mounted therein and illustrated in a deployed mode;

7 FIG. 10 is another enlarged cross-section side view of a short box of a pickup truck with the first preferred bed extension deck and ramp assembly mounted therein and shown in a folded stowed position;
FIG. 11 is an enlarged view of the detail circle 12 in FIG. 10, showing the first preferred extension deck and ramp assembly in an intermediate position during folding;
FIG. 12 is another enlarged view of the detail circle 12 in FIG. 10, showing the first preferred extension deck and ramp assembly in the folded or stowed position;
FIG. 13 is a perspective view of the bed extension deck and ramp assembly according to the second preferred embodiment of the present invention;
FIG. 14 is a perspective view of the ramp end section of the ramp assembly with its lock bars extended;
FIG. 15 is a side view of the second preferred bed extension deck and ramp assembly in a horizontal alignment, ready to start the stowing process;
FIG. 16 is a side view of the second preferred bed extension deck and ramp assembly in a horizontal alignment, with the ramp member thereof stowed inside the foldable deck segment and the bed extension deck;
FIG. 17 is an enlarged side view of the ramp end section of the ramp assembly with the lock bars extended and the bar locking mechanism in a release mode;

8 FIG. 18 is a side view of the second preferred bed extension deck and ramp assembly in a horizontal alignment, with the end section inserted inside the deck extension and the foldable deck extension being partly folded;
FIG. 19 is a side view of the second preferred bed extension deck and ramp assembly in a horizontal alignment, with the foldable deck extension and ramp assembly being completely folded flat over the bed extension deck;
DETAILED DESCRIPTION OF THE FIRST AND SECOND
PREFERRED EMBODIMENTS
There are two preferred embodiments of the present invention presented herein. The first and second preferred embodiments of the bed extension deck and ramp assembly according to the present invention are described herein below with reference to the attached drawings.
Referring firstly to FIG. 1, a modern short-box pickup truck 20 is illustrated therein as a reference, to better understand the foldable bed extension deck and ramp assembly according to the first preferred embodiment of the present invention.
This short-box pickup truck 20 has the preferred bed extension deck mounted therein in a folded mode, such that the tailgate of the short-box truck can be closed. The foldable segment 22' of the bed extension deck is visible in FIG. 1. As it will be understood, the first preferred bed extension deck has a length of slightly under 6 feet in a folded mode, and a total length of about 8 feet when extended over the tailgate of the truck in a deployed mode. For clarity, only the box portion 24 of that pickup truck 20 is illustrated in subsequent drawings included herein.

9 Referring to FIG. 2, the bed extension deck 22 is preferably fastened to the floor of the box 24 of the pickup truck by brackets 26 bolted to the front end of the deck 22. The floor 28 of the truck box 22 is shown in cross-section shading in FIG. 2. Also in FIG. 2, it can be appreciated that the ramp member 32 is telescopically mountable into the bed extension deck 22. In this illustration, the ramp member 32 is shown in an extended, deployed mode. Although the box 24 is a short box, the ramp member 32 has a length of about 8 feet or more in a deployed mode.
As it will be better explained later, the bed extension deck 22 has a piano-type hinge 34 thereon retaining a foldable rear segment 22' to a fix front segment 22. Similarly, the ramp member 32 has a piano-type hinge 36 thereon retaining a foldable rear portion 32' to a front portion 32. The foldable rear segment 22' and portion 32' have a respective length of 2 feet or more.
In FIGS. 3 and 4, it can be seen that a pair of latches 38 are used to stiffen the ramp member 32 in use. The latches 38 are mounted to both portions 32' and 32 to prevent folding of these portions about the hinge 36 in use.
The capacity of each latch 38 is preferably one ton or more.
-The ramp member 32 has a shoulder 40 along both side edges thereof.
These shoulders 40 are used for enclosing the latches 38 within the width of the ramp member and serve as guides for guiding the ramp member 32 inside the bed extension deck 22. The ramp member 32 also has a pair of handles 42, or handle-openings as illustrated, on its rear end to push and pull the ramp member 32 in and out from the bed extension deck 22 by hand.

Referring now to FIGS. 5 and 6, the structural frame system of the bed extension deck 22 will be explained. The bed extension deck 22 has two structural channels 50 forming its sides; a first metal plate 52 on top, and optionally a second metal plate 54 closing the bottom of the bed extension deck. The preferred channels 50 are nominal 6 inch channels with 2 inch flanges.
A front vertical guard plate 56 is preferably provided along the front end of the deck 22 to protect the front end of the truck box against damage from equipment loaded on the deck 22. The foldable segment 22'of the extension deck 22 is separated from the front segment 22 along cut line 58.
As it will be understood, the top and bottom plates 52, 54 and the structural frame system 60 are also separable at line 58.
Below the top plate 52, there is provided an array of flat bars mounted on edge and jointly forming the structural frame system 60 of the bed extension deck 22. The structural frame system 60 is made of transverse flat bars 62, which extend the full width of the bed extension deck 22, between the channels 50. These transverse flat bars 62 are spaced apart about 16 to 24 inches.
The transverse flat bars 62 provide substantially the entire structural strength of the bed extension deck 22 to prevent a transverse deflection of the deck 22. A series of longitudinal flat bars 64 are mounted between the transverse flat bars 62, also at spacings of about 16 to 24 inches. The longitudinal flat bars 64 are precisely cut at a right angle, and are precisely fitted between the transverse flat bars 62. The longitudinal flat bars 64 are held to the transverse flat bars 62 by means of angle joiners 66 and rivets 68. The preferred flat bar dimensions for both the longitudinal flat bars 64 and the traverse flat bars 62 are 2.5 inch high by 1/4 inch thick. The preferred angle size for the angle joiners 66 is 2.5 inch by 2.5 inch by 1/4 inch thick. The preferred material of construction of all structural members, sheets and top plate of the bed extension deck and ramp assembly is aluminum.
It will be appreciated that the longitudinal flat bars 64 and angle joiners 66 prevent the transverse flat bars 62 from canting under load, thereby maintaining their full strength despite sagging of the top plate 52.
Another important feature in the preferred bed extension deck 22 is that the top plate 52 is fastened to the array of flat bars 60 by means of rivets (not shown) and angle clips 70 that are affixed exclusively to the longitudinal flat bars 64. The reason for the mounting of the angle clips 70 to the longitudinal flat bars 64 is to further prevent the canting of the transverse flat bars 62 when the top plate 52 is sagging under load.
Although the structural frame system 60 of the bed extension deck 22 has been described herein, the structure of the ramp member 32 is built in a similar manner as the bed extension deck 22 and therefore, the advantages described herein-above also apply to the ramp member 32.
The forward end of the ramp member 32 has a dolly 80 mounted to each side thereof; only one side is visible in FIGS. 7 and 8. Although only one dolly is visible, it is believed that the person skilled in the art will understand the structure, mounting and operation of these dollies from the following description.

The views in FIGS. 7 and 8 is a longitudinal cross-section view through the flanges of the near side channel 50. The dollies 80 are rolling along the bottom flanges of these channels 50 and are guided sideways against the web of these channels.
For reference purposes, the frame portion 60 of the bed extension deck 22 is represented by the dimension 'A' and the ramp storage compartment under the frame portion, is represented by dimension '13' as seen in FIG.
8.
The front end of the ramp member 32 has two arms 82 pivoted to a respective side thereof. These arms 82 are part of the dollies 80 mentioned before. These arms 82 are made of structural angles for example. Each arm 82 extends forward inside the rear end of the bed extension deck 22, into the ramp storage compartment 'W. Each arm 82 has a pair of closely-spaced in-line casters 84 mounted to its forward end, and a cap plate 86 extending above the casters 84. The casters 84 have a larger diameter than a height of the structural angle of the arms 82. The casters 84 on one arm 82 are aligned with the lower flange 88 of a respective structural channel 50 enclosing a respective side of the bed extension deck 22. The dollies 80 guide the ramp member inside the bed extension deck 22, and for support the front end of the ramp member 32 inside the bed extension deck 22.
There are provided inside the side channels 50, a pair of horizontal guide blocks 90 affixed to the web of the channels 50 at the rear end of the channels. These horizontal guide blocks 90 are mounted in a parallel relationship with the lower flange 88 of a respective channel 50. The clearance between these horizontal guide blocks 90 and the lower flanges 88 of the channel 50 is basically the same as a distance between the lower segment of the casters 84 and the cap plate 86 of each arm 82 plus a free sliding fit. Each dolly 80 is thereby movable in a precisely fitted manner inside a gap between a respective guide block 90 and a flange 88, at the end of its rearward travel.
A stopper block 92 is mounted vertically to the web of each of the side channels 50 at the rear end of the ramp storage compartment T'. These stopper blocks 92 are used to prevent the dollies 82 from sliding out of the ramp storage compartment 'B'. In use, the cap plate 86 and/or the rear caster 84 of a dolly abuts against a stopper blocks 92 on the rear end of the channels 50 so as to retain both dollies 80 captive inside the bed extension deck 22.
The guide block 90 and the stopper block 92 shown in FIGS. 7 and 8 are those mounted to the far side channel 50, while the casters 84 are those facing the near side channel 50, on the near side dolly 80. The drawing has been prepared in this manner for convenience to better explain the operation of the dollies 80.
It will be understood that when the ramp 24 is fully deployed, each dolly 80 is held fix between the lower flange 88, the stopper block 92 and the guide block 90, with the arms 82 extending rigidly, parallel with the floor of the bed extension deck 22. A cross-member (not shown) may be provided across the bed extension deck 22 between the dollies 80 to add stability to these dollies 30.
Because of the arm 82 extending rigidly rearward on each dolly 80, the ramp member 32 is pivoted at a distance from its front end. When the ramp member is lowered to the ground, as illustrated in FIGS. 2 and 7, the front end of the ramp member 32 extends higher than the arms 82 to reach a same height 'H' as the floor surface 52 of the bed extension deck 22.
The pivot points 94 on the arms 82 and ramp member 32 can be relocated to other pivot holes 96 along the sides of the ramp member 32 to accommodate different heights of pickup truck bed, so that the ramp' s front end, in use, is of a same height 'H' as the floor surface of the bed extension deck 22. This feature is advantageous for driving a vehicle over the ramp member 32 and the bed extension deck 22 without encountering a transition step at the intersection of both elements.
Because each dolly 80 has closely spaced casters 84, the arms 82 of these dollies 80 are stable and rigidly held to resist downward forces when the ramp is used normally. The arms 82 of these dollies 80 are also stable and rigidly held to resist upward forces when a vehicle climbs the ramp with substantial momentum. For reference purposes, the spacing between the casters 84 is about 1.5 to twice the diameter of one caster.
For reference purposes, the bed extension deck 22 may have overall dimensions of 48 inch wide by 96 inch long when unfolded. The ramp member 32 with its dollies may have dimensions of 47-3/4 inch wide by 95-1/2 inch long. The deployed ramp member 32 has a slope of about 23 degrees, when used on horizontal grounds.
Referring now to FIGS. 9 and 10, the folding of the bed extension deck will be described. As mentioned before, the preferred bed extension deck 22 has a separation 58 therein and a foldable rear portion 22'. The rear portion 22' is foldable on the piano-type hinge 34 from a flat position over the tailgate 98, to a vertical position inside the tailgate 98 of a short box pickup truck.
When the foldable segment 22' of the bed extension deck 22 is in a flat position as shown in FIG. 9, the space available over the deck 22 is substantially the same as inside a full-length box of a conventional pickup truck. The truck can be used with the tailgate 98 open to carry common building materials and other equipment that is best transported in a conventional pickup truck.
When the foldable segment 22' of the bed extension deck is in a folded position as shown in FIG. 10, the bed extension deck 22 and ramp member 32 do not prevent the tailgate 98 of a short box pickup truck from being closed as if nothing was mounted in the truck box 24.
Referring to FIGS. 11 and 12, cross-section views of the bed extension deck 22 during folding are illustrated. Firstly, the latches 38 on both sides of the ramp member 32 are unlocked and tucked under the shoulders 40 along the edges of the ramp member 32 before the ramp member 32 is inserted fully inside the storage compartment 'B' of the extension deck 22.
The ramp member 32 is stowed inside the storage compartment '13' so that the second hinge 36 is vertically inline or slightly rearward relative to the first hinge 34 as illustrated in FIG. 11.
The tilting upward of the foldable segment 22' of the bed extension deck causes the ramp member 32 to move backward, and causes the foldable ramp portion 32' to move forward and downward such that the second hinge 36 is automatically pulled forward or backward to lie in a position near to or on a median 100 of the angle of displacement 'C' of the foldable segment 22' of the bed extension deck.
The ramp storage compartment 'B' together with its channels 50 and the ramp's dollies 80 jointly constitute a guiding arrangement for maintaining the ramp member 32 in a parallel alignment with the bed extension deck.
Because of this guiding arrangement, the ramp member is easily adjustable inside the storage compartment 'B' for maintaining the second hinge 36 in alignment with the median line 100. The bed extension deck 22 with the ramp member 32 stowed therein are easily foldable by hand.
When the bed extension deck 22 is in its folded position, as shown in FIG.
12 the tailgate 98 of the pickup truck can be closed to retain the bed extension deck 22 in that folded position. Springs and shock absorbers can also be used to assist in the working of the bed extension deck between a deployed and a folded positions.
When the bed extension deck is folded back to a flat alignment, the ramp member 32 returns to its initial position inside the storage compartment '13', and can be withdrawn for normal use.
Although the bed extension deck 22 and ramp member 32 are described herein as accessories for a pickup truck, it will be appreciated that this invention can also be used in other environments including loading docks, trailers, cargo vans, etc.
Referring now to FIGS. 13-19, the bed extension deck and ramp assembly according to the second preferred embodiment 120 of the present invention will be described. The distinguishing characteristics of the bed extension deck and ramp assembly according to the second preferred embodiment of the present invention is that the foldable deck extension 22' and the ramp end section 124 of the ramp assembly can be folded flat over the bed extension deck 22 in a stowed mode. The bed extension deck and ramp assembly according to the second preferred embodiment 120 can be completely concealed from view in a short box of a pickup truck with the tailgate closed, under a tonneau cover for example, when not in use.
The extension deck and ramp assembly according to the second preferred embodiment 120 has many similarities with the extension deck and ramp assembly according to the first preferred embodiment 22, 32. Therefore, the following description is limited to the distinguishing characteristics in the second preferred embodiment. For convenience, the labelling of the elements in both embodiments is the same as long as the function of the corresponding elements do not differ substantially from each other.
A first characteristic in the extension deck and ramp assembly according to the second preferred embodiment 120 is a pair of lock pin and button assemblies 122 mounted to the side of the foldable deck extension 22'.
When pushed in, the lock pins prevent the ramp dollies 80 from sliding inside the foldable deck extension 22'. When pulled out, the lock pin and button assemblies 122 allows a free sliding of the dollies 80 and the ramp member 32 inside the bed extension deck 22.
The extension deck and ramp assembly according to the second preferred embodiment 120 has a ramp end section 124 that is retained to the ramp member 32 by a link segment 126. The stiffening of the link segment 126 relative to the end section 124 and the ramp member 32 is effected by a pair of lock bars 130 movably mounted inside a pair of channel link members 132. The ramp end section 124 also has on each of its sides, a respective bar locking mechanism 134 for locking the lock bars 130. A transverse handle 136 is mounted to the nose of the ramp end section 124 and is used for operating the mechanisms 134. It will be appreciated that the bar locking mechanism 134 on one side of the ramp end section is a mirror image of the other mechanism on the other side, and therefore, only one side is illustrated. The handle 136 operates both mechanisms 134 simultaneously.
Referring particularly to FIGS. 13 and 14, the ramp end section 124 is connected to the ramp member 32 by the link segment 126. This link segment 126 has a pair of piano hinges 36 mounted thereto, and a pair of channel-link members 132. A pair of lock bars 130 slide fitly, such as deadbolts, from inside the ramp end section 124, into a respective one of the channel-link members 132, and in a respective "precise fit" pocket (not shown) inside the ramp member 32. The lock bars 130 are preferably made of high-strength steel. When the lock bars 130 are extended such as illustrated in FIG. 14, the ramp end section 124 forms a rigid platform with the ramp member 32.
It will be understood that the distance between both piano hinges 36 on the link segment 126 is substantially a same measurement as the thickness of the bed extension deck 22, or slightly more such that the foldable deck extension 22' can be folded a straight angle flat over the bed extension deck 22 with the ramp member 22 inside.
Each lock bar 130 is slid in and out of the ramp end section 124 by way of a respective knob 140 guided along a slot 142 in a respective side wall of the ramp end section 124. Each bar locking mechanism 134 has cams 144, 144' and a link bar 146 to secure the knob 140 in one extremity of the slot 142 or the other, as can be seen in FIG. 14 and FIG. 17. As can be appreciated from these illustrations, both bar locking mechanisms 134 are operated by moving the handle 136 upward or downward. Both knobs 140 and lock bars 130 are free to move along the slots 142 when the handle 136 is in the raised position as illustrated in FIG. 17. When the handle is in the down position, as seen in FIG. 14, the knobs 140 and the lock bars 130 are locked in place by either cams 144, 144', at either ends of the slots 142.
The stowing of the ramp member and the foldable deck extension in the bed extension deck and ramp assembly according to the second preferred embodiment 120 is effected as follows: Starting with a deployed ramp member 32 and ramp end section 124, as illustrated in FIG. 13, the lock pins 122 are pulled out to unlock the ramp dollies 80 from the foldable deck extension 22'. The ramp member 32 and ramp end section 124 are lifted up in a horizontal alignment as shown in FIG. 15. Then, the ramp dollies 80 and the ramp member 32 are slid inside the bed extension deck 22, as illustrated in FIGS. 16 and 17. As this point, or during the lifting of the ramp assembly to a horizontal position, the handle 136 is moved into an upper position, unlocking the movement of the lock bars 130 as previously explained.
The movement of the ramp member 32 along the bed extension deck 22 brings each of the knobs 140 to register into a respective seat 150 on the end of the foldable deck extension 22', as can be seen in FIG. 17. A
further movement of the end section 124 inside the foldable deck extension 22' causes the knobs 140 and the lock bars 130 to move inside the end section 124, and to free up to movement of the hinges 36 on the link segment 126, as can be appreciated by looking at FIG. 18 and FIG. 19.

The deployment of the ramp member 32 and ramp end section 124 in the bed extension deck and ramp assembly according to the second preferred embodiment 120 is done by reversing the steps mentioned above. The moving of the knobs 140 and lock bars 130 is done manually, preferably before the ramp member 32 is moved out of the foldable deck extension 22'. The handle 136 is then position downward in its "in-use" position, thereby locking the lock bars 130 in place.
It should be noted that the handle 136 constitutes a fence on the ramp end section 124 when it is in a raised position. Because of this fence, the ramp assembly 22, 124 cannot be used when the handle 136 is not in a downward "bar locking position".

Claims (8)

What is claimed is:

1. A truck bed extension deck and ramp assembly wherein said ramp assembly being movably mounted inside said bed extension deck;
said bed extension deck having a foldable deck extension hinged to a rear end of said bed extension deck; said foldable deck extension being foldable a straight angle between a first position extending horizontally inline with said bed extension deck and a second position folded flat over said bed extension deck;
said ramp assembly being movably mounted inside said foldable deck extension; said ramp assembly comprising a ramp member, a ramp end section extending from an end of said ramp member and a link segment pivotally mounted between said end of said ramp member and said ramp end section;
said link segment having a pair of hinges, said pair of hinges being spaced apart a distance equivalent to a thickness of said bed extension deck such that said ramp end section being foldable a straight angle relative to said ramp member when said ramp member is stowed inside said bed extension deck and said ramp end section is stowed inside said foldable deck extension.

2. The truck bed extension deck and ramp assembly as claimed in claim 1, wherein said ramp member also having a pair of lock bars movably mounted thereto for selectively extending in said ramp end section and in said end of said ramp member, for preventing a folding movement of said ramp end section and said link segment relative to said ramp member.

3. The truck bed extension deck and ramp assembly as claimed in claim 2, further comprising a bar locking mechanism including a handle, for locking a position of said lock bars when said ramp assembly is in use.

4. The truck bed extension deck and ramp assembly as claimed in claim 3, wherein said handle has a first bar locking position and a second bar release position and said second bar release position constitutes a fence across said ramp end section.

5. A truck bed extension deck and ramp assembly wherein said ramp assembly being movably mounted inside said bed extension deck;
said bed extension deck having a foldable deck extension hinged to a rear end thereof; said foldable deck extension being foldable a straight angle between a first position extending horizontally inline with said bed extension deck and a second position folded flat over said bed extension deck;
said ramp assembly being movably mounted inside said foldable deck extension; said ramp assembly comprising a ramp member, a ramp end section extending from an end of said ramp member and a link segment pivotally mounted between said end of said ramp member and said ramp end section;
said ramp member, said link segment and said ramp end section having common ramp sides and a common ramp width between said ramp sides; said link segment having a pair of hinges extending along said ramp width, said pair of hinges being spaced apart a distance equivalent to a thickness of said bed extension deck such that said ramp end section being foldable a straight angle relative to said ramp member when said ramp member is stowed inside said bed extension deck and said ramp end section is stowed inside said foldable deck extension;
said link segment having a channel-link member and a lock bar movably mounted therein along each of said ramp sides thereof; said lock bars extending through said channel-link members and into both said ramp end section and said end of said ramp member in a ramp-locking position, for preventing a folding movement of said ramp end section and said link segment relative to said ramp member; said lock bars selectively extending out of said channel-link members and said end of said ramp member and withdrawing in said ramp end section in a ramp-release position, for allowing a folding of said ramp end section relative to said ramp member; each of said lock bars having a knob thereon and each of said knobs sliding in a respective slot in one of said ramp sides along said ramp end section;
said ramp end section also having a bar locking mechanism mounted thereto on each of said ramp sides;
said ramp end section also having a nose portion extending across said ramp width along a lowermost portion thereof;
said ramp end section also having a handle mounted to said nose portion, said handle extending across said ramp width and connecting said bar locking mechanisms together;
said handle being connected to and movable up and down about, an axis aligned parallel with said nose portion; said handle being positioned down in a plane of said ramp end section when said lock bars are positioned in said ramp-locking position, and said handle being positioned up above a plane of said ramp end section when said lock bars are movable between said ramp-locking position and said ramp-release position.

6. The truck bed extension deck and ramp assembly as claimed in claim 5, wherein each of said bar locking mechanisms has spaced apart locking cams for retaining said lock bars in said ramp-locking and ramp-release positions respectively.

7. The truck bed extension deck and ramp assembly as claimed in claim 2, wherein said lock bars are made of high-strength steel.

8. The truck bed extension deck and ramp assembly as claimed in claim 3, wherein said handle constitutes a fence across said ramp end section when said handle is positioned up above said plane of said ramp end section.