Apparatus and method for transporting and unloading containers

An apparatus and method for transporting and unloading a container (10, 10A) carrying particulate lading which is removably mounted on a tiltable support frame (76, 76A) pivotally mounted on a highway trailer (54, 54A). At the unloading site, a portable throttle valve assembly (108, 108A) and flexible connecting hose (166, 166A) are connected to the container (10, 10A) and the container (10, 10A) is tilted by the support frame (76, 76A) to an angle above the angle of repose of the lading for gravity unloading of the lading from the container (10, 10A) in to a trailer mounted rotary valve (148, 148A) which forms an air lock over a subjacent pneumatic hopper structure (144, 144A) for pneumatic conveyance of the lading to a storage facility. The height of the discharge opening (46, 46A) in the container (10, 10A) above the rotary valve (148, 148A) during unloading is sufficient to provide a continuous gravity flow of lading from the container (10, 10A) to the rotary valve (148, 148A) at an angle at least generally similar to the angle of repose of the lading being unloaded.

BACKGROUND OF THE INVENTION 
This invention relates generally to transporting and unloading containers, 
and more particularly to an apparatus and method for transporting 
particulate lading in a container from one site and then unloading the 
particulate lading from the container at a second site. 
Particulate ladings, such as polycarbonate or thermoplastic materials, 
synthetic resins, for example, are normally loaded within boxes, bags, 
containers or the like at a site where the polycarbonate plastic material 
is manufactured, and then transported by wheeled vehicle to a site where 
the plastic material is unloaded from the container into a storage 
facility for subsequent use in the manufacture of various plastic end 
products. It is highly desirable that such plastic materials or ladings, 
such as polyethylene pellets, not be contaminated by foreign matter or the 
like as even small amounts of foreign matter or contamination affect the 
quality of the subsequent manufactured products. Heretofore, plastic 
liners or bags such as vinyl or polyethylene liners have been used within 
containers to protect the lading from contamination. The plastic liners 
are normally sealed at the initial loading site and the lading is 
maintained in sealed relation within the plastic liner until unloaded at 
the unloading site, thereby insuring that the plastic lading will not be 
contaminated. Normally, the plastic lading is unloaded at the unloading 
site from the container by a suction or vacuum line extending within the 
container and then is conveyed pneumatically to a storage facility, such 
as bins, silos, or the like, until needed for the production of plastic 
end products. Pressurized air is sometimes used to push or aid in pushing 
the particulate plastic material from a container into a pneumatic 
discharge line for pneumatically conveying the plastic material into the 
storage facility. 
U.S. Pat. No. 4,247,228 dated Jan. 27, 1981 shows a dump tractor or trailer 
having a container secured thereon for transporting sand and a pneumatic 
conveyor is secured to an end of the container for unloading the sand. 
Upon unloading, the container is tilted for discharge into a pneumatic 
conveyor and air is drawn in the container through hatches as the sand is 
dumped from an opening at the rear of the container. The container or 
truck bed is not removable and cannot be loaded at a site separate from 
the dump truck or trailer. 
U.S. Pat. No. 4,449,861 dated May 22, 1984 shows a system for transporting 
plastic articles utilizing a tiltable van which is supplied with 
compressed air for forcing the plastic articles from an outlet at the end 
of the van for discharge into a pneumatic conveyor. The tiltable van is 
fixed to the vehicle and cannot be unloaded at a site separate from the 
dump truck or trailer. 
Prior art unloading systems heretofore have utilized trailers with 
container support frames pivotally mounted for tilting at an end of the 
trailer for unloading particulate lading from an end of the container by 
gravity. However, such prior art trailers have not utilized pneumatic 
discharge apparatus mounted on the trailer forwardly of the rear wheels 
thereof and rearwardly of the rear end of the container for effective 
unloading of the container by gravity upon tilting of the container. 
SUMMARY OF THE INVENTION 
This invention is directed particularly to a transportation system for 
transporting plastic particulate material in a sealed condition from one 
location or site where the plastic lading is loaded into a container 
having a plastic liner or bag therein, to another location or site where 
the sealed liner or bag within the container is broken for unloading of 
the plastic lading from the container. 
The container after being loaded and sealed at the first site is 
transferred to a tiltable container support frame on a highway vehicle for 
transport to the second site where the sealed container is broken and then 
tilted by the tiltable support frame to an angle above the angle of repose 
of the plastic lading within the container for discharge of the lading by 
gravity from the container into a pneumatic discharge line for pneumatic 
conveying to a suitable storage facility, such as a storage bin or silo. 
The container utilized with the apparatus and method of the present 
invention is preferably a standard removable container such as used in 
intermodal transportation in so-called COFC (container on railway flat 
car) service, on container ships, or on highway trailers, for example. 
One end of the container has a pair of doors which are normally latched in 
closed position during transit. Suitable wooden framing members are 
provided within the container adjacent the closed doors to provide an end 
support for a cardboard backing member having a lower discharge opening 
therein and against which the plastic liner or bag is supported. The 
plastic bag is filed with lading from a flexible hose extending within an 
upper tubular inlet extension or neck of the liner adjacent the outer 
upper portion of the container. Upon filling of the plastic bag with 
lading, the extending tubular extension is sealed by suitable banding or 
ties, and thus the lading is sealed within the plastic bag for transport 
to an unloading site. 
The loaded container is then transferred to a tiltable container support 
frame pivotally mounted on a highway trailer body and is releasably 
secured thereon for transport by a highway vehicle to an unloading site. 
At the unloading site, at least one of the end doors of the container is 
opened to expose the bottom discharge opening for the lading in the 
adjacent cardboard backing member and another lower tubular extension or 
neck of the loaded plastic bag is positioned adjacent the discharge 
opening. The inner end of the tubular extension of the plastic bag is 
sealed at its juncture with the bag by a sealing membrane defined by the 
portion of the bag covering the inner end of the tubular extension. This 
sealing membrane must be cut or removed in order for the lading to be 
unloaded from the plastic bag. Thus, the lading is tightly sealed upon 
loading within the plastic bag, and the plastic bag remains in a sealed 
condition until it is opened by slitting the membrane for gravity 
discharge directly into a pneumatic conveyor at the unloading site. The 
container or the plastic bag is not pressurized in any manner during 
unloading and the plastic bag collapses as the lading is removed or 
discharged. Thus, loss of lading after loaded within the plastic bag in 
the container until the lading is discharged into the pneumatic unloading 
system at the unloading site is minimized. 
The gravity unloading of the lading from the container at the unloading 
site is obtained by first tilting the container support frame having the 
loaded container thereon to an angle above the angle of repose of the 
lading and thus the lading flows by gravity from the plastic bag in the 
container through the tubular extension and discharge opening in the 
cardboard backing member into the pneumatic conveying system. 
It is noted that highway vehicles traveling over interstate highways are 
governed by U. S. Federal Regulations for bridges and this controls the 
design of such highway vehicles. Included in such bridge regulations are 
the requirements of a total weight of eighty thousand (80,000) pound for 
the tractor, trailer, and loaded container on the trailer. Thus, the 
so-called tare weight of the trailer is desired to be at a minimum in 
order for a loaded container thereon to carry a maximum amount of 
particulate lading within the container. The trailer comprising the 
present invention has been particularly designed to be within such federal 
regulations but yet to carry a maximum amount of particulate lading. 
Containers of twenty (20) feet in length and having a lading weight of 
between around forty-two thousand (42,000) pounds and forty-five thousand 
(45,000) pounds are normally utilized for the transport of particulate 
lading, such as plastic pellets or the like, which are unloaded 
pneumatically at an unloading site. 
Further, regulations control the length of a trailer with rear tandem axles 
and a maximum length of forty-two (42) feet is permitted. Thus, the 
pneumatic conveying apparatus and the connecting lading conduits between 
the end of the container and the pneumatic conveying apparatus must be 
carefully positioned between the rear end of the container and the rear 
tandem wheels in order to permit an effective and satisfactory gravity 
unloading of particulate lading from the rear end of the tilted container 
to a rotary valve which feeds the particulate lading into an air stream in 
a lower hopper for pneumatic conveyance to a storage site such as a silo, 
for example. A flexible lading conduit connects a throttling control valve 
adjacent the lading discharge opening at the rear of the tilted container 
and a rotary valve mounted on the trailer rearwardly of and below the 
container for receiving the lading at a relatively fast flow rate from the 
container. The pivoted container support frame is mounted for pivotal 
movement at a location spaced a substantial distance horizontally from the 
rear end of the container in order to provide a sufficient vertical height 
for the rear discharge opening in the container to discharge effectively 
the particulate lading from the container by gravity into the rotary 
valve. 
As an example, a container twenty (20) feet in length and loaded with 
polyethylene lading of around forty-four thousand (44,000) pounds may be 
unloaded in around two and one-half (21/2) hours by the present apparatus 
and method with a negligible amount, less than ten (10) pounds, of lading 
remaining in the container after unloading. Prior art apparatus and 
methods utilizing a suction line connected to the container have required 
over four (4) hours for unloading such a loaded container and a 
substantial amount of lading, such as around one hundred (100) pounds or 
more, has remained in the container after such unloading. 
An object of this invention is to provide a transportation system in which 
a standard container is utilized as presently used in so-called COFC 
(container on railway flat car) service, on container ships, or on highway 
trailers, for the transportation of particulate ladings from on site at 
which the lading is loaded within the container, to a second site at which 
the lading is unloaded from the container. 
Another object of this invention is to provide an apparatus and method for 
unloading such a container with a negligible loss of lading during 
unloading of the particulate lading from the container resulting from a 
maximum clean out of the container. 
Still another object of the present invention is to provide a 
transportation system for transporting plastic particulate materials in a 
sealed condition from one location or site at which the plastic lading is 
loaded within the container, and then transporting the loaded container on 
a tiltable support frame of a highway vehicle to another location or site 
where the lading is unloaded by gravity into a pneumatic conveyor after 
tilting of the container support frame thereby to unload the lading by 
gravity from the container into a pneumatic conveyor in a minimum of time. 
A further object of the invention is to provide in such a transportation 
system a wheeled highway vehicle to carry the loaded container from the 
loading site to an unloading site and having a tiltable frame thereon for 
supporting the container so that upon unloading one end of the container 
may be raised above the angle of repose of the lading thereby to provide 
effective gravity unloading from a raised discharge opening in the 
container without the container or plastic bag within the container being 
pressurized in any manner. 
Another object is to provide a highway trailer which is within existing 
federal regulations for transport over bridges of interstate highways and 
includes the mounting of suitable pneumatic conveying means on the trailer 
between the rear end of the container and the rear wheels of the trailer. 
Such conveying means includes a throttling control valve removably 
positioned adjacent the discharge opening of the container and a flexible 
lading conduit from the container to a rotary valve mounted on the trailer 
rearwardly of and below the container to receive the lading by gravity for 
feeding into an air stream in a hopper beneath the rotary valve. 
An additional object is to provide a gravity unloading system for a tilted 
container on a highway trailer in which a pneumatic conveying means on the 
trailer and a rear discharge opening in the container are easily connected 
by a detachable lading conduit prior to tilting of the container on the 
highway trailer for gravity unloading.

Referring now to the drawings for a better understanding of this invention, 
and more particularly to FIGS. 1-4, a container generally indicated at 10 
is provided. Container 10 is preferably a standard container such as 
twenty (20) feet in length used in intermodal transportation such as in 
so-called COFC (container on flat car) service, container ships, or 
highway trailers, and has a pair of sides 12 connected by an end 14 at one 
end. The other end of container 10 has a pair of doors 16 hinged at 18 for 
movement between open and closed positions. Latch-type members shown at 19 
are provided to secure doors 16 in a closed latched position. Container 10 
has a top 20 and a bottom 22. Mounted on the corners of bottom 22 are 
corner fittings 24 which have suitable openings therein adapted to receive 
locking pins for releasably mounting container 10 onto supporting 
transport means, such as highway trailers. 
Container 10 of the present invention is preferably utilized with highway 
vehicles and with the transport of plastic particulate lading, such as 
plastic pellets or the like, used in the manufacture of various plastic 
end products. The plastic particulate materials are normally transported 
from a plant where the plastic pellets or the like are manufactured, to a 
plant at another site where the plastic end products are manufactured from 
the plastic particulate materials. It is highly desirable that such 
plastic materials not be contaminated with foreign matter as the quality 
of the final manufactured product may be affected. Thus, it is desirable 
that the plastic lading be sealed from the environment after being loaded 
into container 10 until unloaded at an unloading site for conveyance to a 
storage facility where the plastic particulate material enters a 
manufacturing process for manufacture of a plastic end product. For this 
purpose, a plastic bag generally indicated at 26 and formed of 
polyethylene having a thickness of around .012 inch, for example, is 
placed within container 10 to receive the lading therein. Bag 26, as shown 
particularly in FIG. 2 has an upper tubular extension or boot 30 which 
receives a flexible discharge hose shown in broken lines at 32 for the 
discharge of the plastic lading therethrough. Upon loading of plastic bag 
26, tubular extension 30 is sealed by a band 34. It is noted that a lower 
tubular boot or extension 36 is provided and a portion of bag 26 closes 
the inner end of extension 36 to form a membrane or closure 38. 
To support loaded plastic bag 26 adjacent end door 16, vertical wooden 
framing members 40 are mounted within container 10 adjacent end door 16, 
and horizontal extending wooden frame members 42 are secured to vertical 
framing members 40. A cardboard or corrugated backing sheet or member 
indicated at 44 and being around three inches in thickness is supported 
against members 42 and a lower discharge opening 46 is provided in backing 
sheet 44. Backing sheet 44 restrains the loaded plastic bag 26 from 
outward movement upon opening of door 16. It is noted that tubular boot 36 
is positioned adjacent opening 46 for discharge of the lading from bag 26, 
as will be explained. In order to prevent lading from collecting in the 
corners of container 10 adjacent discharge outlet 46, suitable diverging 
cardboard wing members shown at 37 on FIG. 9 may be provided to direct the 
lading in bag 26 toward discharge outlet 46 thereby providing a maximum 
Clean out of lading from container 10 and plastic bag 26. 
After loading of plastic bag 26 in container 10 with the plastic 
particulate lading, the loaded container is transferred by suitable 
transfer apparatus, such as a crane or lift truck, for example, onto a 
highway vehicle generally indicated at 48 for transport to another site, 
such as a manufacturing site for plastic end products. Highway vehicle 48 
includes a tractor 50 having a fifth wheel 52 thereon. A trailer indicated 
generally at 54 has a kingpin 56 thereon releasably connected to fifth 
wheel 52, as is well known. 
Trailer 54 has a body including a pair of spaced I-beams 58 and 60. I-beams 
58 and 60 have adjustable support legs generally indicated at 62 mounted 
thereon for supporting trailer 54 when disconnected from tractor 48. A 
rear chassis generally indicated at 64 includes a pair of horizontally 
spaced tandem axles 66 and associated wheels 68. Transverse reinforcement 
members 70 extend between the webs of I-beams 58 and 60. As shown 
particularly in FIG. 6A, a tubular member 72 extends between and is welded 
to the webs of I-beams 58 and 60. Side plates 74 extend between and are 
welded to the outer flanges of I-beams 58, 60 and tubular member 72 is 
likewise welded to side plates 74 for reinforcement of tubular member 72. 
A tilting container support frame is generally indicated at 76 and 
comprises a pair of spaced longitudinal frame members 78 connected at 
their ends by end frame members 80 and 82. Cross members 84 are secured 
between side members 78 for reinforcement. End member 82 has spaced gusset 
web members 86 secured thereto arranged in a box-type construction. The 
inner facing surfaces of box-type gusset members 86 are closed by vertical 
plates 88 which receive the opposed ends of an axle 89 which is mounted 
within tubular member 72 for relative rotational movement. Axle 89 forms a 
pivot for frame 76 which is spaced horizontally from the adjacent rear end 
of container 10 at least one (1) foot and preferably around two (2) feet 
in order to permit discharge opening 46 to be raised vertically a 
sufficient distance upon pivoting of frame 76 for the efficient and 
effective discharge of particulate lading by gravity. Container 10 of 
twenty (20) feet in length may contain lading having a weight of around 
forty-five thousand (45,000) pounds, for example, and upon tilting of 
frame 76 with loading container 10 thereon, high forces are transmitted by 
axle 89 to I-beams 58, 60 and side plates 74 through tubular member 72. 
It is noted that federal regulations restrict the total weight of a tractor 
and trailer with a loaded container thereon to eighty thousand (80,000) 
pounds, and the length of a trailer to forty-two (42) feet. Thus, the 
weight of the trailer is desired to be at a minimum in order for the 
container to carry particulate lading of a maximum amount. 
The other end 80 of tiltable support frame 76 extends upwardly a 
substantial amount from adjacent side members 78 in order to provide 
adequate support for a mounting bracket indicated generally at 90 on the 
outer surface of end 80. Mounting bracket 90 includes a pair of spaced, 
angle-shaped support members 91 which are secured at their lower ends to 
end 80 and extend upwardly therefrom as shown particularly in FIGS. 3 and 
6. Braces 92 extend between the upper ends of support members 91 and the 
upper edge of end 80 to provide reinforcement. The upper ends of support 
members 91 have a horizontal tubular member 93 secured therebetween. 
Pintle hooks 94 are secured to the outer surface of end 80 and may be 
utilized by suitable lift apparatus, if needed. 
A mounting bracket generally indicated 95 includes a support plate 96 
extending between and secured to I-beams 58 and 60. A pair of lugs 97 
extend upwardly from the upper surface of support plate 96 and a hydraulic 
cylinder or ram indicated generally at 98 has a lower end lug 99 mounted 
for pivotal movement on pivot pin 100 extending between and secured within 
lugs 97. A piston rod 101 extending from the upper end of hydraulic 
cylinder 98 has an end lug 102 mounted for pivotal movement about a pivot 
pin 103 received in tubular member 93 between the upper ends of support 
members 91. Thus, upon actuation of hydraulic cylinder 98, end 80 of 
container support frame 76 is moved upwardly and may be raised and lowered 
thereby. Hydraulic cylinder 98 is adapted to raise container support frame 
76 at a maximum angle of around forty-eight (48) degrees with respect to a 
horizontal plane and for unloading, the loaded container 10 is normally 
tilted around three (3) or four (4) degrees above the angle of repose of 
the particular lading. Many of the plastic ladings have an angle of repose 
of around thirty-five (35) degrees and thus, the support frame 76 would be 
raised to an angle of around thirty-seven (37) or thirty-eight (38) 
degrees, for unloading. 
Holddown brackets 104 are provided adjacent end member 82 and holddown 
brackets 106 are provided adjacent end member 80. Holddown brackets 104, 
106 are arranged in vertical alignment with corner fittings 24 on 
container 10 and releasable connecting pins (not shown) releasably connect 
corner fittings 24 with aligned holddown brackets 104 and 106 for 
releasably securing container 10 thereon. It is noted that container 10 
while shown as one length, such as twenty (20) feet, for example, may be 
of different lengths depending upon the weight of the lading being 
transported. The container 10 is normally loaded to the maximum weight of 
lading for the transport vehicle and if the lading being transported has a 
higher unit weight, container 10 could be of a shorter length, such as 
sixteen (16) or eighteen (18) feet in length, for example, and yet be at 
the maximum weight limit for the transport vehicle. For transporting 
containers of different lengths, holddown brackets 106A and 106B shown in 
FIG. 6 in broken lines may be provided. If desired, holddown brackets 106 
could be adjustable along the length of side frame members 78 and move 
between desired locations at which the holddown brackets could be 
releasably secured to the associated members 78. 
After the loading of plastic bag 26 with particulate lading, the loaded 
container 10 is transferred by suitable transfer equipment, such as a 
crane, onto highway vehicle 48 for transport to another site at which the 
lading is unloaded from container 10. 
At the unloading site, a portable throttle valve assembly generally 
indicated at 108, as shown in FIGS. 8, 9, and 12-15, is provided to 
control the flow of lading from container 10 upon unloading of the lading 
from discharge opening 46. Throttle valve assembly 108 includes a main 
valve body 110 which is positioned in longitudinal alignment with opening 
46. The handles 112 are manually rotated to move retainer bars 114 into 
backing sheet 44 behind the inner surface thereof for retaining throttle 
valve assembly 108 in position. A fixed mounting bracket generally 
indicated at 116 is provided on one side of valve body 110 and includes an 
angle-shaped plate member 117 positioned behind associated frame member 
40. Front frame plate member 118 extends from angle-shaped member 117 and 
fits against the front surface of associated vertical framing member 40. 
On the other side of main body 110 is an adjustable or telescoping 
mounting bracket generally indicated at 119 including a pair of fixed 
bracket members 120 receiving slidable bracket members 121 therein. The 
outer ends of removable bracket members 121 include an angle-shaped rear 
plate member 122 engaging the side and rear surfaces of vertical frame 
member 40. A pair of spaced front plate members 123 extend from member 122 
and engage the front surface of frame member 40. Adjusting means 124 
secure members 121 in extended position about associated frame member 40. 
Valve body 110 includes a lading conduit having a butterfly valve member 
125 therein fixed to a shaft 126 having a plate 127 mounted on its upper 
end. An internal threaded nut 128 is secured to plate 127 in offset 
relation to shaft 126 and a bracket 130 has an internally threaded nut 132 
secured thereon. An externally threaded screw 134 is mounted in threaded 
engagement with nuts 128 and 132 and has a handle 136 mounted for manual 
rotation of screw 134. Stop nuts 138 are fixed to shaft 134 and engage nut 
132 at fully opened and closed positions of butterfly valve member 125. 
Thus, the flow of lading from container 10 may be controlled by butterfly 
valve member 125 upon rotation of handle 136. A plexiglas window 140 is 
mounted for vertical sliding movement within guides 142. In order to 
commence the unloading operation, a workman raises plexiglas window 140 
and inserts his hand through the opening formed thereby for slitting 
membrane 38 in bag 26 thereby to start the flow of lading through the 
conduit in which butterfly valve 125 is mounted. The rate of flow of the 
lading may be observed through the plexiglas window 140. 
Referring to FIGS. 16-17, a hopper structure is generally indicated at 144 
into which lading flows by gravity upon being unloaded from container 10. 
Hopper 144 has a generally inverted T-shaped body 146 with a rotary valve 
generally indicated at 148 mounted about axis or shaft 150 for rotation 
within hopper body 146. A horizontal mounting plate 152 extends between 
and is secured to the lower of flanges of I-beams 58 and 60 by suitable 
bolt and nut connections indicated at 154. Hopper body 146 has an upper 
annular flange 156 and a rotary valve intake nozzle indicated at 158 has a 
mating lower flange 160. Suitable nut and bolt combinations 162 secure 
flange 156 and 160 to mounting plate 152 for supporting hopper 144 
therefrom. Mounting plate 152 has a suitable opening therein to permit the 
flow of lading from an intake nozzle 158 extending upwardly from flange 
160. The upper end of nozzle 158 has a swivel joint 164 and a suitable 
flexible hose 166 may be removably connected to the end of discharge 
nozzle 158 by a suitable quick release mechanism illustrated generally at 
168. Flexible hose 166 extends to and is releasably connected to throttle 
valve assembly 108 at container 10. A plexiglas window shown at 170 in 
nozzle 158 may be utilized to observe the flow of lading through flexible 
hose 166 into rotary valve 148 and a battery operated light shown at 172 
may be provided to observe the flow of lading at night or under obscure 
lighting conditions. 
Rotary valve 148 shown in FIGS. 16 and 17 includes a plurality of vanes or 
paddles 174 secured to shaft 150 for rotation therewith. Vanes 174 wipe 
against partitions 176 extending between the sides of hopper body 146 in 
sealing relation and form pockets therebetween to receive lading falling 
downwardly by gravity into hopper 144. Vanes 174 seal the lower portion of 
body 146 from the upper portion thereof and prevent any upward flow of air 
from hopper 144 into the downward flow of lading from nozzle 158 into the 
pockets formed between vanes 174. An air inlet conduit 178 is connected to 
hopper 144 on one side thereof adjacent I-beam 60 and an outlet or 
discharge conduit 180 is secured to hopper body 146 on an opposed side 
thereof adjacent I-beam 58. A suitable releasable flexible hose shown at 
182 may be connected to air inlet conduit 178 at the discharge or 
unloading site to supply air to hopper 144 for the movement of the lading 
to a storage facility, such as a bin, large hopper, or silo where the 
lading may be stored until required in the manufacturing process for final 
plastic end products. A suitable, flexible hose shown generally at 184 is 
releasably connected to the air discharge outlet 180 and leads to a 
suitable bin or silo for storage. 
Referring to the rear end portion of trailer 54 shown generally in FIGS. 10 
and 11, and to the schematic view on FIG. 18, power equipment and suitable 
controls are provided thereon for the entire unloading operation at the 
unloading site. A power drive means is illustrated at 186 comprising a 
gasoline engine having a drive shaft 188 extending therefrom. A pulley 190 
is connected by a drive belt 192 to a hydraulic pump 194 which supplies 
hydraulic fluid through line 196 to hydraulic cylinder 98. Fluid is 
returned from hydraulic cylinder 98 to a reservoir 197 through return line 
100. A suitable three-way valve indicated at 102 is provided to reverse 
the flow of fluid to hydraulic cylinder 98 and is illustrated in FIG. 18 
in the position for lowering of cylinder 98. A drive sprocket 198 is 
connected to an air compressor 200 by drive belt 202 and a suitable blower 
for compressor 200 supplies compressed air to flexible line 182 for 
providing a high velocity air stream passage through hopper 144 and 
entraining particulate lading therein for delivery to the storage 
facility. 
It may be desirable to have an alternate source of compressed air such as 
shown in FIGS. 3 and 6 in which tractor 50 has an air compressor 206 
thereon supplying air through a flexible conduit 208 and quick disconnect 
coupling 210 to air conduit 212 mounted on the outer side of I-beam 60. 
The end of conduit 212 may be connected to inlet conduit line 178 of 
hopper 144 to supply air thereto. 
As shown particularly in FIGS. 10 and 11, the rear end portion of trailer 
54 is particularly adapted to permit workmen to operate in a safe and 
efficient manner during unloading lading from container 10. A platform 214 
s provided between I-beams 58 and 60 with suitable handrails 216 on each 
side thereof to permit manual gripping by a workman. Steps 218 allow a 
workman to easily gain access to platform 214 so that upon trailer 54 
reaching its unloading site, throttle valve assembly 108 may be easily 
positioned adjacent discharge opening 46, and suitable hose connections 
made between throttle valve assembly 108 and hopper 144. 
The sequence of steps involved in loading the container 10 at the first 
site within plastic bag 26 within container 10, then transporting loaded 
container 10 to a second site for unloading of the plastic lading, and 
then unloading the plastic lading from container 10 into a storage 
facility at the second site at which the plastic lading will be utilized 
for the manufacture of plastic products will now be described. 
First, plastic particulate lading is loaded from a suitable flexible 
unloading hose into the upper tubular extension 32 which is releasably 
secured about the unloading hose. Upon loading of bag 26, tubular 
extension 32 is banded by band 34 for maintaining an air-tight relation 
during transit. After the loading of container 10, doors 16 are latched 
and then the loaded container 10 is transferred by a suitable crane or the 
like onto tilting container support frame 36 with corner fittings 24 
vertically aligned with holddown brackets 104 and 106. In this position, 
suitable locking pins releasably secure loaded container 10 to tiltable 
support frame 76 for transit. Highway vehicle 48 is then driven to the 
unloading site. 
At the unloading site, a workman unlatches one of the end doors 16 to 
expose discharge opening 46 in cardboard backing member 44. Then, throttle 
valve assembly 108 is positioned adjacent discharge opening 46 as 
indicated with tubular extension 36 being received within the valve body 
110 adjacent valve 125. After throttle valve assembly 108 has been 
positioned, flexible hose 166 is connected between hopper 144 and throttle 
valve assembly 108. Next, air supply hose 182 is releasably connected to 
air inlet conduit 178 and discharge hose 184 is releasably connected to 
outlet 180. Then, to commence the flow of plastic lading, a workman raises 
plexiglas window 140 and manually slits membrane or closure 38 in plastic 
bag 26 which is positioned adjacent outlet opening 46 and cardboard 
backing member 44 and lading then enters throttle valve body 108. 
Engine 186 is started to supply hydraulic fluid to cylinder 98 for raising 
container support fame 76 and loaded container 10 thereon to an angle with 
respect to a horizontal plane at two (2) or three (3) degrees above the 
angle of repose of the lading. In this position, air compressor 200 is 
started and air supplied to inlet 178 of hopper 144 for pneumatic 
unloading of the lading. A workman observes the flow of lading through 
plexiglas window 140 into the conduit controlled by butterfly valve member 
125 and through plexiglas window 170 at rotary valve 148 to determine the 
amount of buildup of lading at rotary valve 148. Throttle valve 125 is 
suitably controlled to provide the desired amount of lading to rotary 
valve 148 for discharge downwardly into the high velocity air stream for 
conveying to a storage area, such as bins. 
As a specific but non-limiting example of unloading utilizing the apparatus 
and method of this invention, container 10 having a length of twenty (20) 
feet has forty-five thousand (45,000) pounds of polyethylene pellets 
loaded therein which have an angle of repose of around thirty-five (35) 
degrees. Container support frame 76 is tilted to an angle of thirty-eight 
(38) degrees. Compressed air at a pressure of around four (4) psi is 
delivered from the blower at seven hundred (700) cubic feet per minute to 
provide an air velocity of sixty-five hundred (6500) feet per minute 
through conduit 182, inlet conduit 178, hopper 144, outlet conduit 180, 
and conduit 184. Conduits 182, 178, 180 and 184 are four (4) inches in 
diameter and a constant diameter is maintained for the air stream to the 
final storage facility. Under such conditions, a fully loaded container 10 
was unloaded in two and one-half (21/2) hours with a negligible amount of 
lading, less than ten (10) pounds, remaining in the container after 
unloading. This compares with unloading methods utilized heretofore in the 
unloading of container 10 with a suction line connected to the container 
of over four (4) hours while having a substantial amount of lading, over 
one hundred (100) pounds, remaining in the container after unloading. 
Thus, a substantial savings in time and in loss of lading by the present 
transportation system and the present unloading method is provided by the 
present invention. 
FIGS. 19-27 illustrate an improved system for positioning the pneumatic 
conveying means on the trailer and the lading discharge opening at the 
rear of the container relative to each other so that a fast gravity flow 
of lading will result upon tilting of the container on the trailer past 
the angle of repose of the lading for gravity unloading. The improved 
system as will be explained further below includes the means and method 
for connecting the throttle valve assembly to the container and for 
connecting the detachable lading conduit between the pneumatic conveying 
means and the throttle valve assembly in a minimum of time and in such a 
manner as to provide a relatively fast gravity flow of lading from the 
container upon tilting of the container past the angle of lading repose. 
Trailer 54A has a pair of longitudinally extending I-beams 58A and 60A and 
a rear chassis 64A on which tandem rear axles 66A are mounted. Rear wheels 
68A are mounted on axles 66A. A container 10A has a lading discharge 
opening 46A at its rear. A container support frame 76A includes side 
members 78A. Gusset members 86A adjacent the rear ends of side members 78A 
receive an axle or shaft 89A for pivotal movement of container support 
frame 76A thereabout. Shaft 89A is supported on I-beams 58A and 60A for 
pivotal movement of container 10A relative to trailer 54A. Axle 89A 
extends a distance D from the rear end of container 10A preferably around 
twenty-one (21) inches as shown in FIG. 24. Distance D should be at least 
around twelve (12) inches from the rear end of container 10A and axle 89A 
should be mounted a distance D1 below the bottom of container 10A of 
around four (4) to eight (8) inches in order to provide an adequate 
predetermined height of discharge opening 46A above the unloading means 
upon tilting of container 10A for gravity unloading. 
It is noted that discharge opening 46A as in the embodiment shown in FIGS. 
1-18 is provided in a lower marginal portion of a vertically extending 
cardboard backing sheet which restrains a plastic bag in which the lading 
is positioned. Discharge opening 46A is around four (4) inches from the 
bottom surface of container 10A as the floor of container 10A is around 
four (4) inches in thickness. 
As shown particularly in FIGS. 24, 25 and 27, a T-shaped pneumatic hopper 
144A has an integral air inlet conduit 178A and air outlet conduit 180A. 
Hopper 144A is mounted a substantial distance of at least around one (1) 
foot rearwardly of the rear end of container 10A and forwardly of rear 
wheels 68A. It is to be understood that hopper 144A may be mounted 
forwardly of rear wheels 68A on a single axle, if desired, instead of a 
pair of rear axles as shown in the drawings. Suitable flexible hoses are 
connected to conduits 178A and 180A to provide a high velocity air flow to 
hopper 144A for pneumatic conveyance of the lading from container 10A to a 
suitable storage facility. Hopper 144A has an upper annular flange 156A 
and a rotary valve generally indicated at 148A is mounted on flange 156A. 
Rotary valve 148A has a body 200 with upper and lower flanges 202, and 
side flanges 204. Lower flange 202 matches and is secured to upper flange 
156A of hopper 144A. Rotary valve 156A has a rotor including vanes 206 
secured to a shaft 208 and forming pockets 210 between the vanes. A 
resilient wiper 212 is provided adjacent the top dead center position of 
rotary valve 148A which wipes excess lading from the op of pockets 210. 
Shaft 208 fits within bearing sleeves 214 which are secured to plates 216 
fixed to brackets 218 mounted on I-beams 58A and 60A. A sprocket 220 is 
secured to an end of shaft 208 and a sprocket chain 222 connects sprocket 
220 with a suitable hydraulic motor shown at 224 for rotation of rotary 
valve 148A. 
To guide the lading to one side of rotary valve 148A for filling a pocket 
210, a lading deflector generally indicated at 226 is secured to upper 
flange 202 of rotary valve 148A and has a lading deflector plate 228 
therein for guiding the gravity flow of lading into the throat provided 
adjacent resilient wiper or lip 212. Mounted for rotary or swivel movement 
upon upper annular flange 230 of lading deflector 226 is a receiver 
generally indicated at 232. Receiver 232 includes a lower vertical section 
233 and an upper inclined section 234. Lower section 233 has an annular 
flange 235 at its lower end mounted for swivel movement within an annular 
slot formed by Z-shaped retaining bracket 236 secured to upper flange 230 
of deflector 226. Platform 214A over I-beams 58A and 60A has an opening 
237 through which receiver 232 extends. A plexiglas window 170A is mounted 
on conduit section 234 for viewing lading flow into rotary valve 148A. 
Receiver 232, lading deflector 226, and pneumatic hopper 144A are all 
supported by rotary valve 148A on shaft 208. For easily connecting 
detachable lading conduit 166A between receiver 232 and container 10A at 
the unloading site while mounting container 10A so that it obtains an 
adequate height above receiver 232 when the container is tilted for 
gravity unloading, it is desirable to be able to move the upper end of 
receiver 232 toward and away from container 10A. For this purpose rotary 
valve 148A is mounted for pivotal movement about shaft 208 relative to the 
trailer. To effect movement of rotary valve 148A and the upper end of 
receiver 232, an internally threaded sleeve 240 is pivotally mounted at 
242 to pneumatic hopper 144A. An externally threaded shaft 244 is 
threadedly received within sleeve 240 and a manual actuator generally 
indicated at 246 is secured by angle 247 to the lower flange of I-beam 
60A. Manual actuator 246 includes a crank 248 connected to a worm engaging 
a worm wheel secured to shaft 244 for rotation of shaft 244 as well known 
to move rotary valve 148A and receiver 232 about shaft 208. Thus, the 
upper end of receiver 232 may be moved back and forth for positioning at a 
predetermined relation with respect to the discharge opening 46A of 
container 10A and the subsequent connection of flexible lading conduit 
166A between receiver 232 and bottom discharge opening 46A. 
Upon arrival at the unloading site and prior to the connection of flexible 
lading conduit 166A, a vertically extending support frame generally 
indicated at 250 is mounted on container support frame 76A after the 
opening of the rear door on container 10A. Support frame 250 includes a 
pair of vertical frame members 252 having lower ends that are received 
within sleeves 254 secured to the rear corners of container frame 76A. 
Suitable set screws 256 releasably secure frame 250 to container support 
frame 76A adjacent the rear end of container 10A. Horizontally extending 
frame members 258 extend between vertical frame members 252 and 
intermediate support members 260 extend between horizontal frame members 
258. Intermediate frame members 260 have receiving slots formed thereon by 
suitable brackets 262 and set screws 264 thereon. 
A throttle valve assembly shown at 108A is then mounted on vertical support 
frame 250 adjacent discharge opening 46A of container 10A. Throttle valve 
assembly 108A includes a tubular valve body 110A in which is mounted a 
butterfly valve member 125A. A shaft 126A secured to valve member 125A has 
an outer handle 136A thereon for manually controlling butterfly valve 
member 125A. An outwardly flared open ended lading receiving hood 
generally indicated at 266 fits about discharge opening 46A of container 
10A for funneling lading from container 10A through the tubular body 110A 
of throttle valve 128A. A pair of arms 268 are pivoted at 270 to hood 266 
and have their ends received within slots formed by brackets 262 on 
intermediate frame members 260. Hood 266 is accurately positioned by a 
workman adjacent and in horizontal alignment with discharge opening 46A, 
and while held tightly against container 10A, set screws 264 are manually 
tightened against arms 268 for holding throttle valve assembly 108A in 
position. A plexiglas window 140A is slidably mounted in a holder 273 on 
the upper wall of hood 266 for viewing the flow of lading from container 
10A and to permit manual access to the plastic bag containing the lading. 
After positioning of throttle valve assembly 108A, a detachable lading 
conduit generally indicated at 166A is connected between receiver 232 and 
throttle valve assembly 108A. Detachable flexible lading conduit generally 
indicated at 166A has rigid sleeves 274 and 276 on opposite ends thereof 
and sleeve 274 fits within the open end of conduit section 234 of receiver 
232 and is suitable secured therein by set screws. Then, for accurately 
positioning of sleeve 276 on the other end of flexible conduit 166A for 
fitting about the end of valve body 110A, the upper end of conduit section 
238 is pivoted about shaft 208 by rotation of hand crank 248. Next, sleeve 
276 is fitted over tubular body 110A and secured thereto by suitable 
releasable locking means. After this connection, plexiglas window 140A may 
be opened for commencing the gravity flow of lading by manual slitting of 
the plastic bag in which the lading is sealed. Then, the container support 
frame 76A and container 10A thereon are tilted about shaft 208 by 
actuation of the associated hydraulic cylinder to an angle greater than 
the angle of repose of the particulate lading to be unloaded. This angle 
indicated at A in FIG. 26 may be around forty (40) to forty-five (45) 
degrees and upon pivoting about shaft 89A, discharge opening 46A moves 
closer to receiver 232. For this reason, during the tilting of container 
frame 76A, hand crank 248 is simultaneously actuated to move receiver 232 
in a rearward direction so that adequate spacing between receiver 232 and 
throttle valve assembly 108A is maintained without excessive deformation 
of flexible conduit 166A. 
It is noted particularly as shown in FIG. 26 that discharge opening 46A is 
positioned at an angle B preferably of around forty-five (45) degrees with 
respect to receiver 232. Angle B is shown for container 10A in a tilted 
position for unloading and should be at least equal to the angle of repose 
of the lading being unloaded for best unloading results. It is noted that 
receiver 232 as shown in FIG. 27 includes upper inclined section 234 which 
is at an angle of forty-five (45) degrees with respect to vertical section 
233 leading to rotary valve 148A. Thus, the entire gravity flow path of 
the lading from discharge opening 46A to the upper end of rotary valve 
148A is preferably at an angle at least equal to the angle of repose of 
the lading for the best unloading rate. In order to obtain a continuous 
gravity flow path above the angle of repose of the lading, it is necessary 
to have discharge opening 46A at a sufficient height D2 as shown in FIG. 
26 above the upper end of rotary valve 148A to achieve the desired slope. 
A minimum height D2 of around eighteen (18) inches is believed necessary 
and an optimum height D2 of around thirty (30) inches is desirable. A fast 
gravity flow of lading is thereby maintained between container 10A and 
receiver 232 for feeding the particulate lading to rotary valve 148A and 
thence to pneumatic hopper 144A for pneumatic conveyance to a suitable 
storage site or the like. 
An angle B of at least around thirty (30) degrees is believed to be 
required for most particulate ladings in order to obtain a desired rate of 
gravity flow from container 10A. 
Receiver 232 and hopper 144A may be pivoted about shaft 208 an angle C as 
shown in FIG. 26 of preferably around fifteen (15) degrees in opposite 
directions from a centered position in order to obtain the desired 
movement for making the connection between receiver 232 and throttle valve 
assembly 108A. An angle C of at least around ten (10) degrees is believed 
to be required for best results. 
A review of the operation of an unloading cycle is described below with the 
trailer being positioned at an unloading site for unloading the lading 
from the container by gravity and pneumatic conveyance to a suitable 
storage facility adjacent the trailer, such as an adjacent storage bin or 
silo. Support frame 250, flexible lading conduit 166A, and throttle valve 
assembly 108A all of which are detachable are normally transported by the 
trailer but could be available at the unloading site. First, the rear 
doors of container 10A are opened and vertically extending support frame 
250 is mounted on container support frame 76A. Next, control valve 
assembly 108A is pushed tightly against the cardboard backing in container 
10A forming discharge opening 46A and is secured thereagainst by set 
screws 264. Then, flexible lading conduit 166A is mounted between receiver 
232 and throttle valve assembly 108A while hand crank 248 is actuated for 
positioning the upper end of receiver 232 at a desired position with 
respect to discharge opening 46A. Next, a suitable air inlet hose is 
connected to air inlet conduit 178A for supplying high velocity air 
thereto for conveyance of the particulate material fed into pneumatic 
hopper 144A, and a suitable discharge hose is connected from outlet 180A 
to the storage facility. Plexiglas window 140A is opened and the plastic 
bag for the lading is opened for commencing the flow of lading. Then, 
container support frame 76A and container 10A are pivoted to the desired 
angle A while hand crank 248 is actuated for movement of the upper end of 
receiver 232 away from the rear end of container 10A as the container is 
being tilted. Hydraulic motor 224 is then started for rotation of rotary 
valve 140A, and butterfly valve 125A is opened for feeding of the lading, 
such as plastic pellets, into hopper 144A for pneumatic conveyance. A fast 
gravity flow of lading from container 10A is obtained resulting 
particularly from the position of discharge opening 46A relative to 
receiver 232 and rotary valve 148A. 
While preferred embodiments of the present invention have been illustrated 
in detail, it is apparent that modifications and adaptations of the 
preferred embodiments will occur to those skilled in the art. However, it 
is to be expressly understood that such modifications and adaptations are 
within the spirit and scope of the present invention as set forth in the 
following claims.