Composite automotive vehicle, components thereof, and a method of constructing and using the same

An automotive draft vehicle and an independent load platform are provided which are especially adapted for use as the components of a unique composite automotive vehicle. The resulting composite vehicle utilizes the basic carry-pull technique of a conventional composite rig formed from a prior art truck tractor and a semitrailer, but the load platform is captured against lateral movement and does not have the tracking characteristics of a semitrailer. Also, the composite vehicle retains the handling-steering characteristics of the draft vehicle. A method of constructing and/or using the aforementioned composite vehicle and/or the components thereof is also provided. The invention is especially useful in restructuring basic two-axle four-wheel and six-wheel trucks of the lighter duty series for use as the draft vehicle component, and in adapting prior art semitrailers for use therewith as the independent load platform component.

THE BACKGROUND OF THE INVENTION 
1. The Field of the Invention 
The present invention broadly relates to an improved composite automotive 
vehicle for use in transporting payloads. In some of its more specific 
aspects, the invention is also concerned with an improved automotive draft 
vehicle and/or independent load platform, each of which is especially 
adapted for use as a component in the composite automotive vehicle. In 
still other aspects, the invention is concerned with a method of 
constructing and using the aforementioned composite automotive vehicle, 
automotive draft vehicle and/or independent load platform. 
2. The Prior Art 
The payload capacity of automotive vehicles of the type normally carrying 
the entire payload have inherent restrictions. The payload is supported 
entirely upon the integral suspension system and in such instances the 
weight must not exceed the design limitations. Additionally, the steering 
and handling characteristics tend to change as the payload is increased 
and often are adversely affected very markedly as the maximum payload 
design limitations are approached. 
The composite method of transporting payloads is intrinsically much more 
efficient than where the payload is totally carried by the vehicle. This 
concept is based upon a composite arrangement which includes an automotive 
draft vehicle such as a truck tractor as one component and a conventional 
semitrailer as the second component. The resultant composite rig is one in 
which the total payload capacity is only partially carried by the truck 
tractor and the balance is supported on the semitrailer and is pulled. The 
ratio of the total payload capacity to the availabile horsepower rating 
for the truck tractor is greater when using a composite rig and the 
efficiency is much higher. However, composite rigs have a number of 
disadvantages when compared with a singular form truck. The steering and 
drawing characteristics of a composite rig are much different and are 
generally considered to be less desirable. The semitrailer does not tag 
true behind the drive wheels of the truck tractor and special driving 
techniques are required. There is also a tendency for the composite rig to 
"Jack-knife" under certain conditions and thus safety considerations 
usually favor the singular form truck. 
It has been proposed heretofore to increase the payload capacity of a 
singular form truck by extending the length and adding a second drive axle 
and a suspension system and wheels therefor immediately behind the first 
drive axle. This proposal has not proved to be entirely satisfactory. The 
increased payload still must be totally carried by the integral suspension 
system and the disadvantages noted above for vehicles of this type apply. 
There is a further disadvantage when the resultant three-axle truck is 
used to transport a heavy payload over unlevel surfaces. In such 
instances, the weight of the payload is not distributed evenly between the 
axles and there is a tendency to overload at least one axle and its 
integral suspension system beyond the design limitations. 
It is apparent from the foregoing that it would be very advantageous to 
provide an improved composite automotive vehicle for transporting payloads 
which has all of the desirable features and capabilities of singular form 
trucks and composite rigs, while avoiding the undesirable features and 
disadvantages. However, a vehicle having these characteristics was not 
available prior to the present invention. 
THE SUMMARY OF THE INVENTION 
The present invention is concerned with a novel concept for upgrading the 
payload capacity of automotive vehicles of the type that normally carry 
the entire payload upon an integral suspension system. The concept is 
based upon utilizing a composite arrangement of an automotive draft 
vehicle and an independent load platform to obtain the carry-pull 
technique and increased payload capacity characteristic of a composite rig 
while avoiding the disadvantages thereof. The load platform is captured 
against lateral movement and the final composite vehicle has the handling 
and steering characteristics of the singular form vehicle which is 
improved upon. The invention is especially useful in restructuring basic 
two axle four wheel and six wheel trucks of the lighter duty series for 
use as the draft vehicle component and adapting prior art semitrailers for 
use therewith as the independent load platform component. The invention is 
also concerned with a method of constructing and/or using the 
aforementioned composite vehicle and/or the components thereof. 
It is an object of the present invention to provide an improved composite 
automotive vehicle for use in transporting payloads. 
It is a further object to provide an improved draft automotive vehicle 
and/or independent load platform which are especially adapted for use as 
components in constructing the composite automotive vehicle of the 
invention. 
It is still a further object to provide a method of constructing and using 
the aforementioned composite automotive vehicle, automotive draft vehicle 
and/or independent load platform of the invention. 
Still other objects and advantages of the invention will be apparent to 
those skilled in the art upon reference to the following detailed 
description and the accompanying drawings.

THE DETAILED DESCRIPTION OF THE INVENTION INCLUDING THE PRESENTLY PREFERRED 
VARIANTS AND EMBODIMENTS THEREOF 
Referring now to the drawings, and more particularly to FIGS. 1, 2, 10 and 
11, the composite automotive vehicle generally designated as 20 includes 
an automotive draft vehicle 21 and an independent load platform 22. The 
draft vehicle 21 is preferably a prior art two-axle four-wheel or 
six-wheel truck which has been restructured as described more fully 
hereinafter. The load platform 22 is preferably a prior art semitrailer 
which has been especially adapted for use with the restructured draft 
vehicle 21, as likewise will be more fully described hereinafter. In the 
interest of simplifying the discussion, the draft vehicle 21 will be 
referred to hereinafter as truck 21. 
Referring now to FIGS. 1-13 of the drawings, the truck 21 and the load 
platform 22 are provided with a primary ball joint coupler 23 and a 
secondary slide roll coupler 24. The ball joint coupler 23 includes a base 
member 25 securely attached to the frame member 26 of truck chassis 27. 
The base 25 extends upward from frame 26 a suitable distance to be 
described more fully hereinafter and has a socket 28 formed in the upper 
surface thereof of a size and depth for receiving the socket ball 29 in a 
secure seating relationship effective for pulling load platform 22. As is 
best seen in FIG. 5, the socket ball 29 is formed on the lower end of an 
elongated upright member 30 which is securely attached on its upper end to 
frame member 31 of load platform 22. As is best seen in FIGS. 2, 10 and 
11, the combined height of base 25 and the length of member 30 are 
sufficient to support the lower surface of floor 32 of load platform 22 a 
substantial distance above the upper surface 33 of truck chassis 27 for 
the purposes described more fully hereinafter. 
The secondary slide roll coupler 24 includes a slide 34 and a probe 35. The 
slide 34 is formed by spaced upright slide members 36 and 37 which are 
securely joined at their upper ends to frame member 38 of load platform 22 
such as by welding, and on their lower ends to plate 39. The probe 35 is 
securely anchored on its forward end to cross member 40 of truck chassis 
27 such as by welding, and extends rearward past the end of truck chassis 
27 and is positioned with the space 41 formed between the slide members 36 
and 37. The probe 35 is preferably round and is provided with a resilient 
round sleeve or roller 42 which has a longitudinally extending annular 
opening 43 therein of a diameter to easily receive the probe 35 and rotate 
thereon without undue friction. The rear end of probe 35 is inserted 
through the opening 43 and extends beyond sleeve 42 a distance sufficient 
to expose the transversely extending opening 44 therein. A stay pin 45 is 
inserted through opening 44 and is locked therein by means of cotter pin 
46 for the purpose of retaining roller 42 on probe 35, and also for the 
purpose of temporarily keeping load platform 22 on truck 21 in the event 
of malfunction of coupler 23. 
As is best seen in FIGS. 5, 6 and 7, the ball joint coupler 23 and the 
slide roller coupler 24 are positioned along the longitudinal center lines 
of the truck chassis 27 and the load platform 22. Thus, the load platform 
22 is captured on its forward end by means of ball joint coupler 23, and 
on its rear end by means of slide roll coupler 24, with respect to 
substantial lateral or transverse movement relative to the centerline of 
truck chassis 27. This double coupling method is unique as it allows full 
articulated movement between the truck chassis 27 and the load platform 22 
under any dynamic conditions associated with transversing unlevel surfaces 
while preventing substantial lateral movement. 
In view of the foregoing discussion and with reference to FIGS. 1-13 of the 
drawings, it will be recognized by those skilled in this art that the 
restructured prior art truck 21 comprises a chassis 27 including a front 
or steering axle 47 and a rear or drive axle 48 which are supported at 
either end by wheels 49 and 50, respectively. The frame 26 extends between 
the axles 47 and 48 and is supported thereabove in a conventional manner 
by a prior art suspension system carried by the steering axle 47 in the 
vicinity of point 55, which is not shown in the interest of simplifying 
the drawings, and the suspension system 51 carried by the drive axle 48. 
The restructured prior art load platform 22 has a chassis including a tag 
axle 52 supported at either end by wheels 53. The tag axle 52 carries a 
suspension system 54 for supporting the frame member 31 thereabove. The 
base member 25 is preferably located along the longitudinal centerline of 
truck chassis 27 and at about the designed payload center of gravity with 
respect to the front and rear suspensions 55 and 51, respectively. This 
provides for the proper relative loading of the front suspension 55 and 
the rear suspension 51 initially and prevents overloading of each 
individual axle in excess of the design limitations. It also prevents 
undue lightening of the front end of chassis 27 with the accompanying poor 
steering and handling characteristics when heavy loads are hauled. 
The independent load platform 22 has what may be considered to be two 
payload zones, one being a forward payload zone in the general vicinity of 
the primary coupler 23 and the second being a rear payload zone in the 
general vicinity of the secondary coupler 24, which provide a total 
payload capacity for the composite vehicle 20. The maximum capacity of the 
front payload zone is equal to the original payload capacity of the basic 
truck 21, which in turn is largely dependent upon the design capacity of 
the front and rear axles 47 and 48 and suspensions 55 and 51, 
respectively. The maximum capacity of the rear payload zone is equal to 
the design payload capacity of the tag axle 52 and the suspension system 
54. The weight of the payload in the front zone is transferred to and is 
carried or borne by the front and rear axles 47 and 48 and the front and 
rear suspensions 55 and 51, respectively, by means of primary coupler 23. 
The payload weight in the rear zone is carried or borne by the tag axle 52 
and the suspension system 54, and is the extended payload capacity which 
is pulled by the truck 21. Thus, the truck 21 and independent load 
platform 22 are structured so as to be capable of forming a composite 
vehicle 20 in which the total payload capacity is only partially carried 
by the truck 21, and the balance of the payload capacity is carried by the 
load platform 22 and is pulled by the truck 21. This resulting composite 
method of load hauling increases the effective length of the load bearing 
platform of a singular form truck, and also results in an increase of the 
total maximum payload capacity thereof. These advantages are gained while 
retaining the normal steering and handling characteristics of the standard 
singular form truck prior to restructuring. 
The above described composite method of load hauling overcomes the payload 
design limitations, both in load platform length and total payload 
capacity, that are imposed by the suspension systems of standard four 
wheel or six wheel truck units. These limitations are most restrictive in 
the lighter duty truck series and the present invention shows the greatest 
improvement therein, but there is also substantial improvement in 
restructuring standard truck units of the more costly larger and heavier 
sprung series. In each instance, the available horsepower for a given 
truck unit is capable of hauling a much larger total payload capacity 
without sacrificing the original handling and steering characteristics. 
The primary coupler 23 and the secondary coupler 24 are employed to achieve 
a precise controlled joining or coupling of the truck 21 to the load 
platform 22. The resulting double-coupling method is unique and is 
necessary to facilitate the desired conditions of payload distribution and 
load platform control and obtain a justaposed position which is closely 
adjacent to the rear of the truck cab 58 and rear axle 48. The double 
coupling method is also necessary to insure a positive articulated 
positioning of the load platform 22 in all dynamic movement planes except 
for the designed capture thereof in the lateral plane at the points of 
coupling with the primary and secondary couplers 23 and 24. The lateral 
capture creates a true tagging effect and the load platform 22 does not 
trailer as a semitrailer. This is responsible for the composite vehicle 20 
retaining the handling and steering characteristics of the basic truck 21. 
The lateral capture also makes it possible to position the load platform 
22 closer to the truck cab 58 and maintain the necessary minimum clearance 
between the front end 56 of load platform 22 and the rear end 57 of cab 
58. 
Articulated movement of the load platform 22 under any dynamic conditions 
associated with transversing unlevel surfaces, with the exception of in 
the lateral plane, is important to the system of the invention. The 
articulated movements made possible by primary coupler 23 and secondary 
coupler 24 allow the truck drive axle 48 and the wheels 50 supporting the 
same, and the tag axle 52 and the wheels 53 supporting the same, to assume 
wide range differential positions both above and below the normal or 
horizontal surface of the road plane. Perhaps even more important, the 
arrangement prevents any one axle from dynamically assuming the total 
payload carried by platform 22, and it also prevents individual axle 
overloads in general which are above the maximum design limitations. Thus, 
the invention overcomes one important disadvantage which is generally 
typical of tag axle adaptations due to the limited differential movement 
between the various axles when traversing unlevel terrain. 
As is best seen in FIGS. 4-7 and 10-13 of the drawings, the primary coupler 
23 provides the towing capture between the truck 21 and load platform 22, 
and also allows the load platform 22 to move dynamically around the 
longitudinal roll axis and pitch axis with the coupler 23 serving as the 
primary axes. As is illustrated in FIG. 10 and shown in phantom line at 60 
in FIG. 7, the frame member 31 is supported above the upper surface 33 of 
frame 26 by coupler 23 on the forward end, and by the suspension system 54 
and frame members 59 on the rear end, a distance sufficient to allow the 
probe 35 to assume the illustrated positions within space 41 while 
maintaining a clearance between the rear end of the truck frame 26 and the 
platform frame member 31. Similarly, as illustrated in FIGS. 7 and 11, the 
front end 56 of load platform 22 is positioned behind cab 58 a distance 
sufficient to allow clearance of the rear end 57 when the probe 35 assumes 
the illustrated position in space 41. As is best seen in FIGS. 4, 6 and 7, 
the position of the probe 35 in space 41 when the composite vehicle 20 is 
on level terrain is intermediate the extreme upper and lower movements of 
probe 35 illustrated in phantom line at 60 and 61. The relative positions 
of the probe 35 in the space 41 of coupler 24 in instances where the rear 
wheels 50 are on level ground and the wheels 53 are on unlevel ground are 
illustrated in FIGS. 12 and 13. The positions assumed by the socket ball 
29 and socket 28 are likewise illustrated therein and are further 
illustrated diagramatically in FIG. 5. It is apparent from the foregoing 
that both the coupler 23 and the coupler 24 provide for relative dynamic 
movement between the truck 21 and load platform 22, at their respective 
points of capture and along the centerlines, around the longitudinal roll 
axis and in the vertical or pitch planes regardless of the position of the 
socket ball 29 in socket 28 or the position of the probe 35 in the space 
41. Additionally, as is best seen in FIG. 6, the pin 46 extends fully 
across the rear surfaces of slide members 36 and 37 and in the event of 
the malfunction of coupler 23 due to socket ball 29 becoming dislodged 
from socket 28, the load platform 22 will be retained on truck 21 until 
the malfunction is corrected. 
The restructuring method or system of the present invention includes a 
number of important improvements and unique advantages. Some of these are 
summarized below, as follows: 
1. An extension is added to a standard truck bed. The resulting extending 
length is equal to at least the area supported by, or under the influence 
of, the tag-axle assembly that is mounted under the load platform at a 
position of tandem with reference to the truck drive axle. 
2. An extended load-weight range is provided. The load increase over the 
original "carry only" capacity of the truck is equal to the net capacity 
of the tag axle. 
3. The invention provides a unique composite loading system which includes 
a truck and an independent load platform. The inventive system retains the 
basic two axle four-wheel or six-wheel type of handling-steering 
characteristics and thus does not require special driving techniques. 
4. In the inventive system, full bed loads, i.e., loads with more than 
normal rear platform overhang of the drive axle, have a natural tendency 
to stabilize the front steering wheels of the truck to the road, rather 
than causing a lightening of the front end and a consequent road drift 
condition. This latter condition is often characteristic of overhang loads 
on standard prior art trucks. 
5. Under winter driving conditions in snow and ice, the tandem-like 
arrangement of the tag-axle and lateral capture of the load platform 
provide for positive forward movement stability with a minimum of 
conventional drive-wheel sideward "kickout". 
6. The load platform may be easily adapted for use as a mobile base for 
field tooling, process equipment and the like that is generally mounted 
permanently upon a truck chassis. This adaption allows important economies 
as inexpensive lighter duty trucks replace higher priced heavier sprung 
trucks of the type that totally "carry" an equivalent load-range. This 
adaption also allows the load platform to be detached from the truck for 
long or short term field positioning, use of the truck unit for multiple 
purposes, or ease of servicing of the truck at overhaul facilities. The 
load platform also may be used as the fabrication base for equipment or 
tooling apparatus as material is processed through the manufacturing 
phase, and a truck unit is not required until delivery is made. 
7. The inventive system is adaptable to any standard truck series and will 
take a selected truck into an increased load-range. The system is also 
adaptable to all truck body styles, such as van, dump, tanker, flatbed, 
grain box, or other. 
8. The inventive system provides for increased wide-range axle differential 
vertical and roll movements and better unlevel surface transversing 
ability than conventional tag-axle attachments of the type used for 
extending the length of a truck bed. 
The foregoing detailed description of the invention and the accompanying 
drawings are for purposes of illustration only, and are not intended as 
being limited to the spirit or scope of the appended claims.