Car Loading Apparatus

Abstract

There is disclosed a method and apparatus for assembling and loading cartons into transport vehicles such as trucks and railway cars. The apparatus includes a turning mechanism in combination with a conveyor for orienting a plurality of cartons into unit stacks which are assembled into tiers of stacks having pre-selected dimensions to fit a given cargo space. Mechanical means are then used for inserting the assembled stacks into available cargo space to make a tight fit.

Description

BACKGROUND OF THE INVENTION

The present invention is related to article or carton handling, and pertains more particularly to a method and apparatus for assembling cartons into stacks of predetermined dimensions to fit a particular cargo space.

Fruits, vegetables and other produce are usually shipped from packaging plants to consumer outlets in cartons having generally rectangular sides. Such cartons usually have to be handled several times before being loaded on a transport vehicle to be shipped to consumer outlets. For example, the cartons may be loaded onto pallets and placed in storage areas until loaded into trucks or freight cars for transport. The cartons usually have to be loaded or stacked by hand onto the pallets and then transferred again by hand from the pallets to a truck or freight car. The loaded pallets normally cannot be loaded into the transport vehicle because of incompatible dimensions. That is, the cartons normally will not closely fit the space available either as to lateral dimensions or vertical dimensions. For example, the vehicle may be wide enough to take 2 1/2 pallet loads and high enough to take 1 1/2 pallet loads. Moreover, the roof of most vans and railway cars are not high enough to permit a lift truck to raise a pallet high enough to place it atop another stack. Thus, a great deal of manual handling which is both slow and expensive becomes necessary.

This problem is compounded because cartons differ in size from packer to packer and trucks and freight cars also differ in dimensions. Skilled loaders are normally employed to stack cartons in a truck or railway car in a manner so that they will not shift or vibrate when the vehicle is under way. Such cartons are normally overlapped and interlocked to make a snug pack. Loading in this manner is slow, and also expensive because of the time involved and because loaders normally receive a premium for stacking cartons over a certain height.

The above-described manner of handling cartons is particularly troublesome in industries where cartons must be handled a number of times before being placed on a transport vehicle for shipment to a distant market. An example of such an industry is the lettuce industry.

In accordance with present practice, heads of lettuce are placed in boxes or cartons when harvested in the field, placed on a field truck, as shown in "Industrial Refrigeration" May, 1954, page 16, and then taken to a cooling plant where they are cooled before loading into railway cars and vans for shipment to consumers. Existing cooling chambers are not tall enough or of correct width to receive stacks of cartons of sufficient height and width to fit the cargo space of present railway cars and vans. Therefore, in order to fill railway cars and large vans to capacity, layers must be added to such stacks, and the shape of the stacks must be altered by hand.

SUMMARY OF THE INVENTION

It is the primary object of the present invention to provide a method and apparatus to overcome the above problems of the prior art by providing means to assemble cartons into stacks of a pre-determined dimension.

Another object of the present invention is to provide apparatus for orienting layers of cartons into unit stacks and assembling said unit stacks into multi-unit stacks.

A further object of the present invention is to provide an apparatus for arranging layers for cartons into stacks to fit a given cargo space.

A further object is to provide method and apparatus to transport and deposit arranged stacks into given cargo space.

A further object is to arrange tiers on paper pallets that facilitate mechanical loading and unloading of the vehicle by lift trucks.

A further object is to teach a method for loading lettuce cartons on field trucks to facilitate later mechanical handling.

In accordance with the present invention, a conveyor mechanism is provided with an apparatus for orienting layers of cartons into tiers of selected height and assembling a plurality of the tiers and layers into a stack of selected dimension. The assembled stack is then oriented and deposited into the cargo space.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and advantages of the present invention will become apparent from the following description when read in conjunction with the accompanying drawings wherein:

FIG. 1 is a plan view of a harvesting and shipping operation employing the present invention;

FIG. 2 is a perspective view of a preferred arrangement of cartons at point of harvest for presentation to the apparatus of the present invention;

FIG. 3 is a perspective view similar to FIG. 2;

FIG. 4 is a plan view of a preferred embodiment of the apparatus of the present invention;

FIG. 5 is an elevational view of the apparatus of FIG. 4;

FIG. 6 is a detailed view of the turning mechanism of the apparatus of FIG. 5 and FIG. 6;

FIG. 7 is an elevational view of an alternate embodiment of the present invention;

FIG. 8 is a plan view of the apparatus of FIG. 7;

FIG. 9 is a detailed plan view of an assembler and lift section such as shown generally at the right hand portion of the system shown in FIG. 4;

FIG. 10 is an elevational view partially in section of a portion of the assembler and support means of FIG. 9;

FIG. 11 is a fragmentary view of a portion of FIG. 10;

FIG. 12 is an elevational view of a portion of the support mechanism of FIG. 10;

FIG. 13 is a schematic layout of a hydraulic circuit for the apparatus of FIG. 4;

FIG. 14 is a front elevational view of an alternate embodiment of the present invention;

FIG. 15 is a plan view of the embodiment of FIG. 14;

FIG. 16 is a side elevational view of the embodiment of FIG. 14;

FIG. 17 is a schematic layout of a hydraulic control system for the embodiment of FIG. 14;

FIG. 18 is a schematic layout of an electrical system for the embodiment of FIG. 14;

FIGS. 19-22 are schematic illustrations of the operation of the embodiment of FIG. 14.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now to the drawings and in particular to FIG. 1, there is illustrated a schematic layout of a harvesting and shipping operation as carried out, for example, in the lettuce industry and incorporating the present invention. In accordance with the flow diagram of FIG. 1, a field truck 10 is provided with a plurality of suitable pallets 12 covering the bed or load-carrying platform. As the field truck or vehicle 10 is moved through the fields, cartons 14 are hand-loaded onto the pallets on the trucks without cross locking (Stabliization of the stacks may be accomplished by inserting sheets 13 between upper layers of the stack as shown in FIG. 2.) in a manner as shown in FIG. 2 and FIG. 3. Sheets 13 are pulled stepwise by handles 15 to stabilize added cartons. After the truck is loaded, it is taken to the processing or cooling plant where the load is removed by means of a giant lift truck 16 where the cartons are either placed in a storage area during the busy season or placed directly onto conveyor means 18 for movement into a cooling chamber 20.

After the cartons of lettuce have been cooled in a cooling chamber 20, they are then moved by suitable conveyor means to a storage area 22 to await shipment, or directly to a carton stacking and arranging machine according to the present invention. The apparatus of the present invention generally designated by the numeral 24, is constructed and arranged for turning and assembling the cartons into stacks and loading the cartons into a suitable transport vehicle, such as a van or railway car.

The present invention has its greatest efficiency and, hence, utility when loading an end-loading van or railway car. That is, a vehicle having a door at one end and opening to the full width of the cargo space. With such vehicles, stacks of cartons fitting the width and height of the vehicle can be moved by lift truck through the door and fitted into place between the side walls of the vehicle. The entire cargo space of the vehicle can then be easily filled with stacks in this manner.

Vehicles having side doors (e.g. railway cars) present a special problem because a lift truck must turn 90.degree. after entering the door to deposit its load. If the cargo door is wide enough, then at least the ends of the cargo space can be filled with little difficulty, leaving the turning space at the door unfilled. At least a part of the cargo space near the door can also be filled. However, if the proper dimensions exist with respect to the door width, cargo space width, and lift truck width, this space can be entirely filled. In other words, the present invention is useful in connection with filling all types of cargo spaces, although it is particularly adaptable to end-loading vehicles.

As applied to the lettuce industry, cartons of lettuce are preferably stacked in a manner as shown in FIGS. 2-3, on conventional wooden pallets 28 or on special fiberboard slip pallets 30 such as disclosed in Application Ser. No. 133,795, entitled "Loading-Handling Pallet and Method" and filed Apr. 14, 1971. The cartons are loaded in this manner on pallets carried by the field truck. These loaded pallets are then normally transferred at the cooling plant to the bed or platform of a dolly 32. The pallets are loaded preferably with one carton directly over another in individual or unit stacks forming two tiers, as indicated, of multi-unit stacks of a height which can be accommodated by a cooling chamber 20. This height is normally five layers for existing cooling chambers whereas existing transport vehicles, such as vans and railway cars, may take from six to twelve layers of cartons per tier. Thus, we solve the problem of mechanical handling of stacks of cartons which must be accomodated by a cooling chamber having a maximum of five layers permissible and a transport vehicle that can accomodate a larger number of layers.

In order to avoid confusion, the term unit stack will be used to designate a single vertically oriented row of cartons. A plurality of these unit stacks constitute a multi-unit stack or simply, a stack. A row of unit stacks will constitute a tier. Thus, a stack may constitute one or more tiers of two or more unit stacks.

The width of the transport vehicle is also another dimension that must be accomodated by the system. Because of the absence of the interlocking of the tiers, as shown in FIGS. 2-3, some means such as tape 34 or staples 36 may be necessary to enhance the stability of the stack of cartons. Sheets 13 are used for temporary stability in the field loading phase, and are normally removed completely when the field truck load 10 is completed.

Referring now to FIGS. 4-6, there is illustrated a preferred embodiment of a loading platform and stacking machine in accordance with the present invention. The apparatus comprises suitable support means including a platform 38 for supporting suitable loading means, such as a conventional fork lift truck 40 and for supporting the load at a suitable height to accomodate the support floor of a transport vehicle 42. The stacking apparatus comprises in combination, suitable conveyor means comprising a plurality of endless belts 44 supported by an idler pully 46, driving pulleys 48 and a plurality of support rollers 50. The conveyor is driven by a suitable motor 52 which is preferably reversible for purposes to be described and which may be either electric or hydraulically driven. This stacking machine includes an upending or rotating mechamism comprising a plurality of substantially L-shaped arms having a normally horizontally-directed arm 54 and a normally vertically-directed arm 56 pivotally mounted for rotation about a shaft 58. This mechanism is operated by means of suitable power means such as a hydraulic motor 60 connected to an arm 62 attached in a suitable manner to the shaft 58. Suitable guide and stop means such as a stop member 64 may be provided for stopping the stack of cartons at a suitable position in front of the door and aligned with the interior walls of the transport vehicle. This stop means is preferably movable and mounted, such as by means of a pair of wheels or rollers 66, to ride on overhead rails 68 above the cartons and is adjusted to a suitable stop position by means of hydraulic motor or ram 70. Suitable guide means, such as a plurality of vertically spaced belts 72 and 74, may also be mounted or disposed adjacent each side of the conveyor to prevent cartons from tumbling from the stack as it passes along the conveyor to a loading position. This guide means may be driven by a suitable motor 76.

In operation, the above-described apparatus receives two stacks of thirty cartons per stack, as shown in FIG. 2. The belts 44 move the two stacks to vertical arm 56. The machine now carries a pair of pallet loads 78 and 80, each of which comprises a stack like that represented in FIG. 2. Each pallet load comprises two tiers; each tier comprising five layers of three cartons in a tier. The two pallet loads together contain sixty cartons stacked five cartons high. These cartons, or stacks of cartons, are moved with the forward end or edge against the upright arms 56, with the lower cartons and pallets resting on the conveyor itself and the lower arms 54 extending out to the edge of the sixth tier in the stack. This entire stack is then rotated 90.degree. completely re-orienting the stack such that the once horizontal layers become vertical stacks and the once vertical stacks become now horizontal layers with the cartons each standing on its edge, as shown in broken line just to the right of shaft 58. In this position, the once upright arms 56 have tilted to the right between the plurality of belts, lowering the stack of cartons such that they now rest again on the plurality of belts 44.

Repeated action as just described results in the accumulation of stacks of cartons held between belts 72.

The accumulated tiers of cartons are then moved by the belts 44 to the right between guide belts 72, 74, driven by a motor 75, to stop member 64, thus forming an appropriate stack of such a width that the correct numbers may be selected to fit snugly into the open end of a van 42.

The number of stacks upended by the turning mechanism is usually different than the number required to fill the cargo space. The conveyor area behind the turnover mechanism is preferably long enough to permit accumulation of several stacks in excess of that required for each lift truck load deposited in the cargo space.

The lift truck 40, now having lift platform or forks adjusted to a width suitable to fit the van or vehicle 42, moves forward from the position shown in FIG. 4 and selects a stack of a width to fit the van 42. The lift truck then moves directly forward across the conveyor belts 44, between guide and compression means comprising belts 76-77, and deposits the load into the van. It is, of course, necessary that the motion of the conveyor be stopped, or at least the movement of the cartons to the right stopped, during the time that the lift truck 40 moves across the conveyor belt. The compression and/or guide means 76-77, may be necessary in most instances where a close fit normally exists between the stack and van walls. The lower cartons in the stack will tend to bulge or expand due to the weight of cartons from above. This expansion and space between the stacks may cause the selected stack or stacks to exceed the width of the van. Thus, the compression means permits the formation of a closely packed and stable load. When the cartons settle onto the floor of the van, the lower cartons bulge or expand into engagement with the side walls.

A control station or console 82 within reach of the lift truck operator when the truck is in the position as shown in FIG. 4, permits the operator merely to reach to one side to the control panel 82 and manipulate the necessary buttons and switches necessary for arranging the cartons in a properly oriented stack and presenting them to a position to be selected and loaded into the awaiting transport vehicle.

The above-described operation, of course, assumes that the orientation described properly fits the receiving van or transport vehicle and that transporting the cartons on the side as illustrated is satisfactory. Alternate orientations of the stack can be accomodated in that the above-described conveyor is reversible, and also an alternate embodiment for such contingency is provided in FIGS. 7-8, as will soon be described.

It is also apparent that some provision must be made for removing the cartons from the conveyor by means of lift truck 40 without interference of the lift truck with the conveyor belts when no pallets are used in a loading operation. In this connection, suitable supporting means, such as a plurality of support members 84, extend between the belts 44 and are provided wit sufficient space therebetween 86 to receive the forks of the loading truck 40. These support members 84 are preferably movable vertically between and with respect to the belts 44 to lift and support the cartons above the belt, allowing sufficient clearance to permit the forks to extend beneath the cartons. An embodiment of this type support means will be described in detail below with respect to FIGS. 9-11.

It is, of course, apparent that pallets either of the wooden type or of the paperboard type may be used to support the stacks in the van. If pallets are to be used, they are simply placed against the upright arms 56 so that when the stack is rotated 90.degree., it then rests upon a pallet which in turn is resting on the conveyor belt 44. With the use of such pallets, the above-mentioned lift and support mechanism becomes unnecessary.

It is, of course, possible to operate the above machine in a manner that the above-described cartons may be loaded in their upright position as originally presented to the machine. Such an operation would be necessary where cartons are designated as having a top or a side which must be kept up or where the cartons must rest in such a particular position. With this operation, of course, it would be necessary for the conveyor and rotating mechanism to be reversible and the lift truck runway and support platform be positioned at the left side of the rotating mechanism, as viewed in FIG. 4. With such an arrangement, the cartons are separately received and assembled to the right, as shown in FIG. 5 and described above, until a suitable number of tiers are received. The conveyor is then reversed and the rotating mechanism then loaded with a sufficient number of tiers to form the lift truck load and rotated back to the left or counterclockwise direction to rest in the original upright position.

If the cartons have no preferred or designated top position, then a suitable mechanism or apparatus, as illustrated in FIGS. 7-8, may be utilized to accomplish the desired result where the cartons must be flatwise rather than edgewise.

Referring specifically to FIGS. 7-8, there is illustrated an apparatus comprising a conveyor belt 88 for moving stacks of cartons to a position on a loading platform to be manipulated by a lift truck 90 and placed and loaded on a van or railway car 92. This arrangement comprises a first rotating or turnover mechanism generally designated by the numeral 94 and comprising a plurality of arms of generally L configuration having a horizontal arm 96 and a vertical arm 97 mounted for rotation about an axis or shaft 98 and powered by hydraulic motor means 100 connected such as by an arm 102 to the arms 96-97. A second rotating or turnover means 104 is mounted or disposed downstream of the first turnover mechanism and comprises generally a plurality of L-shaped arms having horizontal arms 106 and vertical arms 107 mounted for rotation about an axis or shaft 108 and powered by a hydraulic motor 110 connected by an arm 112 to rotate the arms 106-107.

Suitable guide and retaining means, such as a stop arm or plate 113 and a latch dog 114, may be supported on an overhead carriage 116 which is supported by suitable wheels 118 and 120 on suitable overhead rails 122. This guide-and-retaining means serves to hold the stack together with the tiers in their upright position, as the entire stack is moved to the right along the conveyor to a position in front of the lift truck to be placed into the transport vehicle. The entire apparatus may be provided with suitable guide means such as a plurality of belts 124 and 126, as described above, for retaining the stack in its upright position as it travels the length of the conveyor belt. Suitable guide means for guiding and compressing the load or stack may comprise suitable short belt arrangements such as indicated by numerals 128 and 130. The support platform may be provided with suitable guide ways 132 and 134 for engagement by the wheels of the lift trucks 90 to assist the lift truck operator in properly guiding the stack into the transport vehicle.

The above-described arrangement permits an almost continuous straight line mode of operation in assembling and stacking a plurality of cartons and loading them directly into a transport vehicle. In carrying out the present invention, stacks of cartons normally comprising two tiers, each comprising three stacks, five cartons high for each stack, are fed onto the conveyor belt, at the left, normally resting on suitable pallets 136 and are moved forward against the upright arms 97 and above the horizontal arm 96. At this point, it is necessary to determine the dimensions of the transport vehicle into which the cartons will be loaded. Once the dimensions are established, a suitable number of tiers are selected to fill the cargo space. The arms 96-97 are preferably telescopic with the end thereof extended outward to the edge of the selected number of stacks. This selected number of stacks, designatd by the letter A, is then rotated 90.degree. to stand on the edges of the cartons to form a stack B, which is then moved to the right along the conveyor 88 where it assembles together with othe similar stacks against the L-shaped upright arm 107 and resting over the horizontal arm 106. The horizontal arm 106 is extended sufficiently to select the desired number of stacks which will form the horizontal layers to fit the height dimension of the transport vehicle. A suitable number of stacks are selected to form a large stack designated by the letter C and rotated clockwise 90.degree. to form a stack D of a size properly oriented to fit the dimensions of the transport vehicle. This stack is then appropriately seized between the retaining means 113 and 114 and moved by conveyor means 88 to an assembly area 89 in front of the lift truck where it is then manipulated by the lift truck into the vehicle 92, as shown in FIG. 8 when pallets are used, the assembly area 89 may simply be a smooth flat platform such as stainless steel having a slick surface. The pallet 136 under the first stack is removed when the second stack is formed, but may be positioned to receive the final stack by placing it against the upright arm 107 such that the stack rests thereon when rotated again to rest on the conveyor means 88.

The use of pallets can greatly improve the handling of the load with the transport or lift truck, and eliminates the need for special support means to lift and support the stacks of cartons above the conveyor belt.

In the event that it is necessary or desirable to load the cartons into a vehicle without the use of pallets, some means as mentioned before must be provided for permitting the lift truck to remove the cartons from the conveyor belt without interference.

Referring now to FIGS. 9-12, such means are provided and illustrated primarily in connection with the embodiment of FIGS. 4-6, although it may be readily provided for the embodiments illustrated with respect to FIGS. 7-8 and FIGS. 15-20. This apparatus for supporting the load above the conveyor belt will be described with respect to the embodiments of FIGS. 4-6, and thus will have like numerals designating like elements.

Referring now to FIG. 9, there is illustrated a top fragmentary view of a portion of the apparatus of FIG. 4 as viewed from directly above the area of the conveyor means where the lift truck removes the stack of cartons from the conveyor. In this view, a plurality of belts 44 are shown traversed by a plurality of tines 138 of a lift truck 40 with the overlying position of the plurality of cartons 140 shown in solid lines. A plurality of round elongated pegs 142 are shown extending upward between the belts and between the tines or fingers 138 of the lift truck 40. These pegs are preferably supported by means of a movable plate or platform 144 which is moved in various positions by means of a plurality of hydraulic motors 146, 148, 150 and 152 (FIGS. 10-11). As can best be seen in FIG. 10, the pegs 142 extend between the belts and engage the bottom of the cartons 140 and push them a few inches above the belts 44. The pegs 142 are also spaced apart to permit the tines 138 of the lift truck to extend therebetween above the belt and below the cartons 140. The lift truck then lifts the stack of cartons above the belts 44 and moves across the belt, as illustrated in FIG. 12, with the wheels riding on pegs 142 above the belt and deposits the load or stack of cartons into the vehicle 42. After the cartons have been placed in the vehicle 42, the lift truck 40 then backs across the belt or conveyor riding on the pegs 142 and moves back onto the platform 138 where the operator then, from control panel 82, controls the assembly and the depositing of another stack into position in front of the lift truck to be taken into the transport vehicle.

The pegs 142 are preferably operable by means of the control motors 146-152 to be positioned in three different positions, as shown in detail in FIG. 11. The pegs are preferably provided with the means to maintain an uppermost position designated by E, an intermediate position F, and a lower position G. The G position is below the belts 44 and permits the cartons to rest directly on the conveyor belts 44. The two upper positions E and F lift the cartons a slight bit above the belt to permit the insertion of the forks 138 and to support the lift truck in a position above the belts.

Referring to the schematic layout of FIG. 13, a pump 154 draws hydraulic fluid from a sump 156 and delivers it by means of a supply line or conduit 158 having branches 160 and 162. The branches 160 supply fluid to a distributor valve 164 which supplies fluid to either side of a double-acting motor 70 by way of conduits 166 and 168. The double-acting motor 70 is operatively connected for operating the movable stop 64 illustrated in FIG. 5.

A second distributor valve 170 directs fluid alternately to either side of double-acting motor 60 by means of supply lines 172 and 174. The motor 60 is operatively connected to arm 62 for operating the turning mechanism comprising members 54, 56, illustrated in FIG. 5 for rotating the cartons 90.degree.. A duplicate of this circuit may be added to accomodate a second turning mechanism if such is desired in the system.

The supply line 162 is operatively connected to a distributor valve 176 which directs fluid by conduit 178 in parallel to motors 146-153 which are in turn connected for moving the platform 144. These motors are each in turn connected in parallel to return lines 180, 182, and 184, each of which leads to a distributor valve 186 which is operative to direct fluid selectively from each of said lines to return line 188. This arrangement is such that the motors, as shown in FIG. 11, are each provided with three open return passages controlled by valve 186 such that when pressurized fluid is supplied to the inlet by supply conduit 178 such that the piston moves upward to the first return conduit 180 which, if open, permits the pressure to stabilize to maintain all pistons in that position. However, if the first conduit 180 is closed, all pistons continue to move upward to the next return conduit 182 and again if the valve 186 blocks this return, the pistons continue to move up past the communications with return line 184. If valve 186 is positioned such that return line 184 is open, the pistons will stabilize in the top position and maintain the platform and pegs level in the uppermost position. Thus, the position of the support platform depends upon which of the return lines 180 through 184 is open.

Referring now to FIGS. 14-18, there is illustrated an alternate embodiment of the present invention wherein the conveyor means itself is tiltable to stack the cartons. Referring particularly to FIG. 14, there is illustrated an embodiment comprising a support frame 176 for supporting the conveyor or stacking apparatus and a support platform 178 for supporting a lift truck 180 at the height of the conveyor means and a transport vehicle 182. The rollover mechanism comprises a support frame comprising side members 184 and 186 rotatably supported by shafts 188 and 190 and side members 192 and 194 of the support frame 176. The frame 184-186 supports a first endless belt 196 movably supported on rotatable rollers 198 and 200 which are supported by frame members 202 and 204. The frame members are provided with slides 202' and 204' and thereby are slideably mounted on support members 184 and 186 and powered by hydraulic motors 220 and 222 to move the belt 196 for pushing the stack from belt 206. A second endless belt 206 is movably supported by rollers 208 and 210 in frames 184 and 186. These two endless belts are disposed or mounted at right angles to each other and are adapted to pivot about the axis of shafts 188 and 190 for purposes to be described. The belt 196 is provided with suitable drive means such as an electric motor 212 connected by belt 214 for driving the roller 200. The belt 206 is provided with suitable drive means such as a motor 216 connected such as by a drive belt 218 to drive roller 208. Hydraulic rams 220 and 222 are provided for moving the support frame 202-204 with respect to the frames 184-186, a conveyor 224 may be provided for delivering cartons to the rollover mechanism and a conveyor 226 for asembling and delivering the assembled stack to a position to be secured and loaded by a lift truck into the transport vehicle.

Suitable control circuits for the present apparatus are shown in FIGS. 17-18. FIG. 17 discloses a suitable hydraulic control circuit comprising a pump 228 which draws fluid from a sump 230 and supplies it to a pair of control valves 232 and 234 for supplying fluid to double-acting hydraulic motors 220, 222 and 227.

Illustrated in FIG. 18 is a suitable electrical control circuit comprising a source of electrical power operatively connected for supplying power to a pair of switches 238 and 240 which are operative to control the operation of motors 212 and 216.

Referring now to FIGS. 19-22, there is illustrated a sequence of operation of the present invention, particularly the embodiment of FIGS. 14-16, together with a method of loading that is particularly suitable for facilitating unloading. Referring specifically to FIG. 19, stacks of cartons resting on pallets 242-243 are supplied by conveyor 224 onto conveyor 196 of the turning apparatus. The stacks move up against conveyor 206 and the stacks are then turned over, as shown in FIG. 20, with one stack resting atop the other on conveyor 206. The resulting stack moves then onto conveyor 226, as shown in FIGS. 20-21, where it is assembled with other similar stacks against movable stop means 225. These stacks have been thus formed to fit the height dimension of vehicle 182. A lift truck then selects a stack of suitable width to fit the width dimension, which is then put into the waiting vehicle. The turnover mechanism then may be returned to its initial position, as shown in FIG. 22, with conveyors 196 and 224 reversed to send the pallets 242-243 back to the storage area.

This embodiment may also be operated in reverse as discussed in the FIGS. 4-6 embodiment when it is necessary for the cartons to be presented in a top up position. Also, a pair of the turnover mechanisms may be employed in series or in sequence, as illustrated and described in FIGS. 7-8.

As an example, consider loading a particular vehicle 182 (FIG. 16) having an end opening that is the same width as the cargo receiving area. The cargo space is of a dimension to receive five unit stacks of eight cartons each disposed flatwise. Consider also that it is desirable to unload the cargo by suitable mechanical means such as a lift truck. In order to unload cargo by such mechanical means, it is generally necessary that the cargo rest on suitable pallets. A preferred form of pallet is disclosed in co-pending Application Ser. No. 33,795, mentioned above.

With the above considerations in mind, the cartons from the field are loaded onto the field truck on edge, as shown in FIG. 3. The pallets on the field truck can be loaded in this manner, with two tiers, each tier containing four unit stacks of four cartons on edge. These pallet loads can still pass through the cooling chamber in the usual manner.

As shown in FIGS. 16-19, two pallets 242 and 243, loaded in the manner described, are delivered to the turning apparatus such as by conveyor belt 224. Paperboard pallets 224 and 246 are inserted upright against belt 206 and between the pallet loads. When the stacks are then turned over, as in FIG. 20, the stacks are then resting in their normal flatwise position, one atop another on thin paperboard pallets. When the entire truck load is provided with pallets in this manner, it can be easily unloaded with a lift truck. As shown in FIG. 16, pallets 224' are present under the entire load and pallets 246' are present between the fourth and fifth layers. A lift truck, at the destination, can then select a stack of two tiers having any number of unit stacks up to five and having a height of either four or eight cartons. Thus, the entire load may be easily removed by a lift truck.

In a similar manner, the methods and apparatus of the present invention may be utilized to form stacks of any desired size. For example, different size stacks may be formed to fill a given cargo space like pieces of a puzzle. Any number of stacks may be fitted adjacent or atop each other to fill a cargo space.

From the above description, it can be seen that there is disclosed method and apparatus for assembling a plurality of cartons into stacks of a selected size to fit the opening to the cargo space of a vehicle.

Claims

What is claimed is:

1. Loading means for use in combination with a lift truck and including means for assembling layers of cartons into stacks to be fitted into a three-dimensional cargo space having a support surface, said means comprising:

a support platform having a support surface for supporting cartons at substantially the same height as the support surface of said cargo space;

said support platform including conveying means for conveying cartons to a position to be loaded into said cargo space;

turning means operatively associated with said platform to receive rows of cartons, convert said rows into stacks and deposit said stacks on said platform;

movable stop means operative to move along said conveying means to accumulate and position stacks of said cartons on said support platform; and,

first guide means disposed in laterally spaced vertical planes disposed transverse to and to one side of said conveyor means for alignment with an opening into said cargo space for guiding selected stacks into said cargo space; and,

support means including second guide means disposed on the opposite side of said conveying means from said first side means to support and guide a lift truck in alignment with said first guide means for guiding said lift truck for moving said stack into said cargo space.

2. The invention of claim 1 wherein said turning means comprises a pair of support surfaces disposed at a fixed right angle to one another and each of said surfaces operative to tilt to and from the surface of said conveying means.

3. The invention of claim 2 wherein said support surfaces each comprise endless belt means, and one of said belt means is movable when in its vertical position along the other of said belt means.

4. The invention of claim 2 wherein said conveying means comprise a plurality of endless belts disposed in parallel relation; and

said turning means comprise L-shaped arms which are pivotally disposed between said belts.

5. The invention of claim 4 comprising means extending between said belts and movable to support said stacks of cartons above said conveying means to permit removal therefrom by a lift truck.

6. The invention of claim 4 wherein said arms are adjustable in length to adjustably select a predetermined number of cartons.

7. The invention of claim 1 comprising adjustable support means to lift and support said cartons above said conveying means and for supporting said lift truck for traversing said conveying means.