Telescopic ramp

A compact ramp construction includes a series of nestable, telescopically extendable modules which are connected via an intermediate module to a base that detachably anchors one end of the ramp to a loading surface and which storably supports the ramp when the modules are nested. In one embodiment, the intermediate module is slidably connected to a pair of inclined slots on the base which raises the intermediate module to clear an edge of the loading surface as the nested modules are telescopically extended and lowered to another surface. Each one of the nestable modules has a pair of parallel side members that are spaced apart by an attached overlapping cross member. A single lug attached to the free end of each side member slidably engages an uppermost surface of a corresponding side member in an adjacent module and cooperates with the cross member of that module to support a load. In another embodiment, the intermediate module is hingedly connected to the base such that when the modules are nested, the ramp is stored by being pivoted about its hinges to lie folded against the base. Instead of a lug at the free end of each side member, the free ends of a second cross member in each module partly overlie corresponding side members of an adjacent module and cooperate with the first cross member thereof to support the load. All of the cross members provide a series of steps in a plane between loading and unloading surfaces.

FIELD OF THE INVENTION 
The present invention relates generally to a loading ramp and more 
particularly to a ramp having nestable modules that may be telescopically 
extended. 
BACKGROUND OF THE INVENTION 
The currently extensive usage of small vehicles such as snowmobiles, all 
terrain vehicles, motorcycles, and rideable work vehicles such as lawn 
mowers, frequently necessitates the transportation of such vehicles to and 
from recreational and work locations. A problem commonly experienced 
relates to the safe loading and unloading of a vehicle as well as to 
transporting and storing of a suitable loading ramp since small trucks or 
trailers are frequently used and little storage space is available. As a 
result, makeshift loading and unloading arrangements using wood planks and 
the like for loading and unloading purposes may be used. Safety may then 
be deferred in favor of convenience which places the operator at risk 
together with his equipment. 
A portable ramp suitable for loading and unloading small vehicles is 
disclosed in U.S. Pat. No. 3,984,891, issued Oct. 12, 1976 to Carl E. 
Weinmann. Although eminently suited to the task, the Weinmann ramp is not 
well adapted for convenient, compact storage. In this regard, the ramp is 
fabricated from a plurality of extruded members that require assembly and 
disassembly each time the ramp is used and then subsequently stored. 
Consequently, the Weinmann ramp is not well suited to domestic 
applications in which apparatus costs and convenience of use are principal 
considerations of ramp selection. 
Recourse to the collapsible ladder art shows a type of construction that 
may be adapted to meet a portable ramp criterion of compactness. In this 
respect, U.S. Pat. No. 3,061,042, issued Oct. 30, 1962 to C. W. Giles 
together with U.S. Pat. No. 4,429,766, issued Feb. 7, 1984 to D. Salvador 
Alimbau Marques each show a ladder construction having a plurality of 
U-shaped modules that slidably nest together. Both Giles and Alimbau 
Marques disclose modules comprising a base and a pair of upright sections, 
with each module being smaller in width than the preceding module which 
facilitates the nesting arrangement when all of the modules are 
contracted. Although this nesting arrangement facilitates the ramp 
criteria of compactness and convenient storage, this arrangement results 
in an unstable ramp structure at the end where the U-shaped modules are 
narrow. Furthermore, a rigid sliding arrangement which is desirable in 
ladders and which is disclosed by Alimbau Marques is undesirable in a ramp 
construction which requires a pivotal quality to accommodate various 
differences in height between loading and unloading surfaces. 
SUMMARY OF THE INVENTION 
A principal objective of the present invention is to provide a portable 
ramp having slidable modules that nest together for compact storage. 
Another provision of the invention is a telescopic ramp structure that may 
be readily extended and contracted as required. 
Still another provision of the invention is a portable ramp having pivotal 
connections which permit the ramp to accommodate various differences in 
heights between loading and unloading surfaces. 
Another provision of the invention is a simplified ramp structure that is 
economical to fabricate. 
The problems associated with the prior art may be substantially overcome 
and the foregoing objectives reached by recourse to my invention which is 
a telescopic ramp that comprises a plurality of pi-shaped modules each 
having a pair of parallel side members including side walls spaced apart 
in slidably nestable relation with corresponding side walls of an adjacent 
module. A first cross member of each module is of uniform length and 
transversly overlaps each pair of the side members and is attached thereto 
in overlying relation adjacent one end of the module. A single lug 
attached to the free end of each side member slidably engages in overlying 
relation an uppermost surface of a corresponding side member in an 
adjacent module, whereby the lug end of each module is held slidably 
captive between the cross member and lugs of the adjacent module.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS 
FIG. 1 illustrates a perspective view of one embodiment of a telescopic 
ramp 10 and the placement of one end of the ramp for mounting on a loading 
floor 11 of a pickup truck 12. Both the floor 11 and the truck 12 are seen 
in a fragmentary, broken line form to show the location of a base module 
13, a perspective view of which is shown in FIG. 6, relative to an endgate 
14 of the truck. In this regard FIG. 7 illustrates a portion of a side 
member 15, a pair of which form the module 13 as shown in FIG. 6. Each 
member 15 is understood to comprise 1 1/2 inch square steel tubing having 
an outwardly facing side wall 16 with an inclined longitudinal slot 17. 
A plan view of the ramp 10 is illustrated in FIG. 2 and will be seen to 
comprise the module 13 followed by a single pi-shaped intermediate module 
18, a plurality of pi-shaped ramp modules 19 and a single U-shaped end 
module 20. A characterizing feature of the ramp 10, best seen in its 
extended form as shown, is that the modules become increasing wider in a 
stepped manner when progressing from the module 13 to the module 20. 
The side members 15 of the module 13 are spaced apart in fixed parallel 
relation by means of a pair of cross members 21. The members 21 each 
consist of 1/2 inch spring steel rod which overlies the pair of members 15 
at each end and which is fastened to the uppermost surfaces thereof as by 
welding. 
Referring next to FIG. 8, there will be observed a base anchor which 
comprises a strap 22 having a hooked end 23 and a flanged end 24. Three 
mounting holes 25 are provided to accept fasteners such as bolts, not 
shown, to securely mount a pair of straps 22 on the floor 11 in registry 
with the members 15 of the module 13. Having regard to FIGS. 6 and 7, it 
will be understood that each member 15 rests upon a corresponding strap 22 
with the end 23 hooked into the open end of the member 15 furthest from 
the endgate 14. The other end of the member 15 abuts the end 24 as 
illustrated in FIG. 7 and is held in position on the strap 22 by means of 
a locking pin 26. The pin leads through an aperture 27 in the end 24 and 
into the foremost end of the member 15 to releasably lock the member 15 to 
the strap 22. 
A perspective view of the module 18 is shown in FIG. 5. The module 
comprises a pair of side members 30 having side walls that are spaced in 
slidably nestable relation with corresponding side walls of the members 15 
in the module 13. The members 30 are held in fixed, parallel relation by a 
like cross member 31 with end portions 32 that transversly overlap the 
members 30 and which are attached thereto, as by welding, in overlying 
relation adjacent one end of the module 18. Retainer means at the opposite 
end of the module comprise a pair of 3/8 inch diameter steel pins 33 that 
fit into corresponding apertures of the facing side walls of the members 
30 as shown. Each pin contacts the outer side wall of its member 30 and is 
welded to both side walls for additional strength. The position of each 
pin 33 will be observed in both of FIGS. 5 and 7 as being adjacent the 
lowermost corner of the free end of its member 30. Each pin 33 extends 
inwardly to slidably engage its corresponding slot 17. With regard to FIG. 
7, it will be understood that the described position of the pins 33 
provides a maximum clearance lift for the module 18 as the pins 33 slide 
upwardly along the diagonally positioned slots 17. The clearance provided 
by this feature raises the anchored end of the ramp 10 when it is extended 
to avoid interfering with the engate 14. When the ramp 10 is contracted, 
the pins 33 slide downwardly along the inclined slots 17 to permit nesting 
of the modules 13 and 18, as well as the plurality of modules 19 and the 
single end module 20, all of which are supported by the module 13 clear of 
the floor 11. 
Each one of the modules 19 includes a pair of side members 35 which are 
also fabricated from 1 1/2 inch square steel tubing. Similar to the module 
18, the members 35 are held in spaced parallel relation by a like cross 
member 36 having end portions 37 that transversly overlap the members 35 
and which are attached thereto, as by welding, in overlying relation to an 
uppermost surface thereof adjacent one end of the module. 
Turning briefly to FIG. 2, it will be noted that the members 31 and 36 are 
of the same length to provide a uniform ramp width. However, the 
overlapping portions of these members vary in length inversely to the 
width of the modules. Observe that in the module 20, which is the widest 
module, there is no overlap for a cross member 38. With this exception, 
the module 20 is otherwise the same as the modules 19. Accordingly, the 
member 38 overlies a pair of parallel side members 39 and is attached to 
the uppermost surface thereof, as by welding, adjacent one end of the 
module. 
In each one of the modules 18, 19 and 20 the free end of each side member 
has attached thereto, as by welding, a single lug 40 for slidably engaging 
in overlying relation an uppermost surface of a corresponding side member 
in an adjacent module. As a result, the lug end of each one of the modules 
19 and 20 is held slidably captive between the cross member and lugs of 
the adjacent module and also functions as a fulcrum. 
Another embodiment of a ramp module is illustrated in FIG. 4 and differs 
from the previously described module 19 only in the form of the single lug 
40. Thus, whereas the lug 40 comprises a generally square steel plate 
welded in overlying relation to the uppermost surface at the free end of 
each side member with an overlapping portion extending inwardly to 
slidably engage the corresponding coplanar uppermost surface of the 
adjacent module, a lug 41 in the embodiment of FIG. 4 is a steel angle. 
Functionally, the lugs 40 and 41 are the same. However, the lug 41 has one 
side of the angle affixed to an inner facing side wall 43 of the member 35 
as shown. Moreover, in order that the uppermost surfaces of all modules 
shall lie in a single plane, the second side of the lug 41 is raised so 
that its undersurface 42 is coplanar with the uppermost surface of the 
side member 35 as illustrated in FIG. 4. 
Whichever lug embodiment is employed, the sliding configuration of a single 
lug at one end of each side member allows a downwardly pivotal movement of 
each module which facilitates contracting all of the modules to a smaller 
overall size. Thus, by permitting each module to pivot downwardly out of 
the plane of its preceding adjacent module, the modules may be contracted 
to form a compact package as illustrated in the plan view of FIG. 3 with 
all of the cross members being arranged in contacting relation as shown. 
Furthermore, ample support for a load is readily provided in this 
arrangement by providing a lug 40 or 41 having sufficient modulus in 
shear. Relational stability between adjacent modules is obtained through 
the frictional resistance that develops between the contacting surfaces of 
each lug and its corresponding side member together with the frictional 
resistance between the contacting surfaces of the overlapping cross 
members and their corresponding side members. Mainly, however, a locking 
tab 44 fastened to the side wall 43, as by welding, is in spaced relation 
with the lug 40 or 41, depending on the embodiment used, and provides a 
gap 45 into which a cross member 31 or 36 may lockingly fit. 
Another embodiment of the present invention is illustrated in FIGS. 9-12. A 
top plan view of this embodiment appears in FIG. 9 as a telescopic ramp 47 
which includes a pair of mounting straps 48 that are attachable to one 
side of the end gate 14. Each strap 48 includes a pair of apertures 49, 
aligned with corresponding apertures in a side wall of the end gate 14, 
through which fasteners, such as bolts 50, are fitted to threadably engage 
nuts 51 interiorly of the end gate. 
The ramp 47 comprises a plurality of nestable modules including a single 
pi-shaped upper end module 52, a plurality of pi-shaped ramp modules 53 
and a single lower end module 54. As shown in FIG. 9, the modules may be 
telescopically extended to form a ramp between the end gate 14 and another 
surface. Conversely, the modules may be slidably contracted in nesting 
relation as indicated in FIG. 12. In the latter position, the ramp 47 is 
stored by being pivoted upwardly via a pair of hinges 55, following an arc 
56, to overlie the straps 48 adjacent the end gate 14. 
The module 52 comprises a pair of parallel side members 57 having side 
walls that are spaced in slidably nestable relation with mutually 
contacting side walls of a pair of parallel side members 58 in the module 
53. This same arrangement applies between all succeeding adjacent pairs of 
modules as may be seen in FIG. 9. 
It will be observed that the hinged ends of the members 57 are bevelled to 
clear the end gate 14 when the ramp 47 is extended and its free end is 
lowered to another surface. 
The side members of the respective modules are all spaced apart in fixed 
parallel relation by means of cross members 59, all of which have the same 
length. The members 59 each consist of a 1/2 inch spring steel rod which 
overlies its corresponding pair of side members in overlapping relation at 
one end thereof where it is secured as by welding. The other end of each 
module is bridged by a shorter cross member as typified by a cross member 
60 in the module 52. The member 60 likewise overlies and overlaps its 
corresponding pair of side members where it is also secured as by welding. 
It will be noted that whereas the members 59 are all of the same length to 
form a ramp of uniform width, the cross members as typified by the member 
60 are progressively longer since the modules become increasingly wider in 
a stepwise manner from the module 52 to the module 54. 
Having regard to FIG. 9, it will be observed that the overlapping portion 
of each member 59 progressively decreases from the module 52 to the module 
54. The cross members that are typified by the member 60, however, have a 
constant overlap so as to engage the uppermost surfaces of adjacent 
modules. Thus, end portions of the members 60 overlap and engage the 
uppermost surfaces of the members 58. 
The purpose of the overlap in the members 59 and in the cross members 
typified by the member 60 is to provide the ramp with an adequate load 
carrying capability. Relational stability between adjacent modules is 
provided by pairs of chocks, shown as short rods 61 and 62, which are 
welded in spaced relation on the uppermost surface of each member 58. The 
overlapping end portions of each member 60 fit between the rods 62 and 61 
and lock its respective module in place when the ramp 47 is extended. 
As regards the chocks, it will be observed that the rod 62 is longer than 
the rod 61 and overlaps the side members of its adjacent module to 
increase the load carrying capability of the ramp. 
When the ramp 47 is extended, a wide space between the members 59 and 59' 
is narrowed to facilitate rolling thereover by a vehicle having small 
wheels. This is effected by adding a cross member 63 which is welded to 
the members 57. 
A similar problem in the module 54 is resolved by the addition of a cross 
member in the form of a bail type handle 64 having ends 65 which are 
pivotably mounted in corresponding apertures located in the side walls of 
side members 66. As best seen in FIG. 11, the handle 64 follows an arc 67 
to a position midway between the members 60' and 59" to reduce the wide 
space therebetween. In addition, the handle 64 may be used to lift the 
ramp and to keep a user's hands clear of the sliding modules as they are 
contracted. When the ramp 47 is stored, the handle 64 is pivoted to rest 
alongside the member 59'" as shown in FIG. 12. 
Similar to the embodiment of FIGS. 1-8, adjacent modules 53 and 54 may be 
extended or contracted by permitting each module to pivot about its rods 
62. Thus, each module pivots downwardly out of the plane of its preceding 
adjacent module to engage or disengage the overlapping end portions of the 
members 60 relative their respective locking chocks. 
It will be apparent to those skilled in the art to whom this specification 
is addressed, that the embodiments heretofore described may be varied to 
meet particular specialized requirements without departing from the true 
spirit and scope of the invention disclosed. For example, whereas it is 
disclosed that the modules become progressively wider, the modules may as 
readily be made progressively narrower. And, having regard to the various 
embodiments diclosed, it will be understood that the load bearing 
relationships between modules need not depend on a lug 40 in the form of a 
steel plate or a lug 41 in the form of an angle. Such lugs may be 
substituted by a second cross member 60 in the form of a rod. Furthermore, 
the lugs or second cross members need not be positioned exactly as 
described since each may be mounted, for example, along either the top or 
bottom surfaces of each side member 35, 52 or 58 with corresponding 
changes in location of cross members 31, 36 and 59. In either arrangement, 
the principle of operation remains the same. Moreover, a flexible mat may 
be used in overlying relation with the ramp for bridging the spaces 
between the cross members to provide a more uniform support for a vehicle. 
Even the spacing and location of the rods 61 and 62 may be altered so that 
they function as respective stops for the members 59 and 60. The foregoing 
embodiments are therefore not to be taken as indicative of the limits of 
the invention but rather as exemplary structures of the invention which is 
described by the claims appended hereto.