US3087598A - Article distribution system - Google Patents

Description

3 Sheets-Sheet 1 Filed 001;. l, 1958 SECONDARY TRAY STATIONS PRIMARY DISTRIBUTOR STATIONS DISTRIBUTOR STATIONS SPACING STATION I/VVE/V TOR J: I I 1 mm mm m I April 1963 w. R. CLORE 3,087,598

. ARTICLE DISTRIBUTION SYSTEM Filed Oqt. 1, 1958 s Sheets-Sheet :5

a 6 90b I GAT GATE DETECTOR SOLEN SOLENOID 76 CIRCUIT f 5 .64 I780 I380 B60 l78b 82b PLY RELAY RELAY '86 0 OLD I72 RII-ILAY I80 I460 I440 I46b DETECTOR CIRCUIT INVENTOR ELZZ/Q/AQW United States Patent 3,087,598 ARTICLE DISTRIBUTION SYSTEM William R. Clore, Columbus, Ohio, assignor to Industrial Nucleonics Corporation, a corporation of Ohio Filed Oct. 1, 1958, Ser. No. 764,579 3 Claims. (Ci. 1983$) This invention relates to branched conveyor systems and routing means for articles carried thereby; and more particularly it relates to an automatic gate control system for distributing a fiow of articles to a plurality of destinations in accordance with indicia borne by said articles.

Although the invention is adapted for modification into various forms and is applicable to a variety of alternate uses, the same is herein illustrated and described more specifically in connection with a postal service installation wherein the system of the invention has utility in expediting the sorting and delivery of mails.

At present, even in the largest postal installations the distribution of sorted and semi-sorted mails is carried out almost entirely by manual means. Since the actual sorting process is a human hand and eye operation, the efficiency of the whole system depends on the degree of utilization which is made to the available labor. In general, however, it is quite impossible to make correct and timely predictions as to the load distribution of incoming mails to be routed to various sorting areas. As a result, it frequently happens that some areas are swamped with a deluge of inpom'ing mails and confusion reigns, whereas in other areas personnel are relatively unoccupied.

It is the practice to conduct the hand sorting operation on the basis of regional destinations such asgeographical areas, states, cities, zones or carrier routes. Accordingly distribution cases are provided having perhaps 50-400 regional separations. Previously it has generally been the'practice to have the contents of .a particular separation box picked up only at appointed times. Often because of scheduling difiiculties as above set forth, the quantity of mail addressed to a particular destination exceeds the capacity of the compartments provided so that sorters must resort to makeshift and unsatisfactory temporary storage expedients which interfere with the routine sorting procedures, thus further slowing up the operation at a .critical time when sorting should be proceeding at top efficiency.

These and other difiiculties are largely overcome by the i system of the invention, whereby trays of mail with coded signal cards attached may be intermixed at random on a conveyor With-the assurance that each will be automati cally and efficiently routed to its proper destination. It is an object of the invention to provide a branched conveyor system having automatic gate control means for distributing a flow of articles to a plurality of destinations in accordance with indicia borne by said articles.

It is another object to provide an "improved coding sys 'tem for article identifying indicia compatible with im proved reliable sensing means therefor.

It is also an object to provide a novel combination of indicia adapted for automatic identification by non-contacting sensing means of the proximity detector type.

Further, more specific and general objects of the invention will become apparent in the following detailed description, taken in connection with the appended drawings, in which:

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veyor of FIG. 2, showing certain elements thereof in elevation.

FIG. 4 is a fragmentary side View of a portion of FIG. 3, taken on the line 44 thereof.

FIG. 5 is a fragmentary section on the line 5-5 of FIG. 4.

FIG. 6 is a section on the line 6-6 of FIG. 5.

FIG. 7 is a block diagram of the electrical circuitry of the invention in accordance with one preferred embodiment thereof.

Referring to FIG. 1, there is shown schematically a portion of a postal installation including primary and secondary mail distribution areas. In the primary distribution area to the left a group of distributors stations are indicated generally by the numerals 1048. Each distributors station as at it includes a plurality of distribution cases as at 2% and 22, each manned by a distributor who sorts mail and distributes the same into a plurality of compartments provided in his distribution case, according to regional destinations. Each group of distributors is supplied with mail on a side ledge conveyor as at 24. In the figure, ten such conveyors are shown entering from the left, it being understood that the conveyors as at 24 and 26 are loaded with incoming mail at a culling and postage cancelling area not shown.

As the individual separations in the distribution cases become full, or at appointed times, the distributors are notified by public address system to place the contents of a certain separation box onto a conveyor belt as at 30 which runs beneath the distribution cases. The belt 30 carries this prirnary sort of loose mail to a tray station as at 4%, where the same is placed in trays adapted to carry signal cards which are inserted into suitable holders on the trays. These trays, containing mail referred to as the primary sort, are placed on a conveyor 5!).

The conveyor 50, which also receives mail trays in a similar manner from the other distributors stations 12- 1h, carries the trays to a stop gate and spacing station 54 which holds and releases the trays one at a time at spaced intervals onto a main feed conveyor 56 which transports the trays to the secondary distribution area shown at the right side of FIG. 1. Conveyor 56 is adapted for automatic diverting onto a plurality of side ledge conveyors 53-68 servicing secondary distribution stations as at 70 which are similar to the primary distributors stations as at It) hereinabove described.

Each of the diverting gates as at 72 is controlled by an automatic card reader as at 74- which reads the signal cards previously inserted into the trays at the tray station as at tilt Each of the card readers is responsive to only one particular combination of indicia. If this combination is detected by the reader on a card carried by a passing tray, the reader as at 74 will operate its associ ated diverting gate as at 72, routing the tray from the feed conveyor 56 to the associated side ledge conveyor as at 58.

This system is shown in more detail by FIG. 2, which illustrates the mechanical features of one gate section in accordance with one preferred embodiment of the invention. A first tray 89, carrying letter mafl 32 and a signal card 84 visually indicating the geographical destination thereof, is shown passing on the feed conveyor 56. It is seen that the signal card 84 is inserted into a side rack 86 provided on the tray 84 A second similar'tray 88, also on feed conveyor 56, is shown approaching the junction of conveyor 56 with the side ledge conveyor 58 which runs at right angles thereto. The tray 88 also carries a signal card 90 which is shown passing in front of the card reader 74 as is further illustrated in FIG. 3.

As the tray passes the card reader, it is seen that a relatively flexible and curved metal deflector guide 92, fixed- 1y mounted on the far (right) side of conveyor 56, urges the tray 88 toward the near (left) side of the conveyor and the card reader 74, so that the near side of the passing tray is pressed into light frictional engagement with a straight and relatively rigid guide rail 94. The guide rail 94 is fixedly mounted on the near side of the conveyor 56 and extends parallel thereto, in order to guide the tray 88 so that the signal card 90 will pass close to the reader 74 without contacting the same.

In connection with the card reader 74 is a cabinet 96 which contains electronic circuitry associated with the reader 74 and a relay system adapted to automatically control the operation of the gate 72, to which the control cabinet is connected by an electrical cable 98.

Although any suitable type of power operated deflection gate may be used, the type illustrated comprises a rubber belt 100 carried on a driven pulley 102 and an idler pulley 104. The pulleys 102 and 104 are rotatably supported on journals comprising the end pieces of a rectangular framework of which the top side member 106 is visible. This framework is pivotally supported at one end on an upstanding post 108 fixedly secured to the floor, the side of the conveyor 56 or other support means. Hence each element of the framework 106 carrying the belt and pulleys is permitted to swing freely in a horizontal direction, being pivoted about the central axis of the driven pulley 102. The pulley 102 is secured to an associated sprocket 110. An endless drive chain 112 passes around both the sprocket 110 and a coplanar sprocket 114 carried on a drive shaft extending upwardly from a gear box 116. The gear box 116 may be supplied with mechanical power through a shaft 118 connected to the drive system (not shown) for the conveyor 56. It is seen therefore that the belt 100 revolves continuously around the axes of pulleys 102 and 104 whenever the conveyor 56 is in motion.

In order to actuate the gate 72 and thereby divert a passing tray onto the side ledge conveyor 58, the frame 106 of the gate is provided with a bell crank 120 whose free end 122 is pivotally secured to the piston rod 124 of a fluid operated piston and cylinder driving device. The end frame 126 of the drive cylinder 128 is pivotally mounted on an upstanding anchor post 130 which may be rigidly secured either to the floor or the side of the conveyor 56. Fluid is conducted to and from the endports of cylinder 128 through a pair of flexible pressure hoses 132 and 134 which connect respectively to a pair of solenoid actuated valves 136 and 138. Valves 136 and 138 are further connected to a source of fluid pressure such as the air pressure supply line 140. It will be understood that if an air cylinder is used to actuate the gate, each valve is provided with an exhaust port vented to the atmosphere, whereas if a hydraulic cylinder is used a suitable return pipe to the oil reservoir will be provided.

Normally fluid pressure from line 140 may be applied to line 134 through valve 138, so that the piston rod 124 will be extended, thus maintaining the gate in the position illustrated, at the side of, and parallel to, the conveyor 56. When a gate energizing signal is received from the cabinet 96 via cable 98, valve 138 disconnects line 134 from the pressure supply line 140 and vents line 134 to the atmosphere or to a fluid return pipe. Simultaneously valve 136 connects line 132 to the fluid pressure supply line 140 so that the piston rod 124 will be retracted, causing the gate to swing across the path of the tray 88 in the direction of the arcuate arrow 141. As the tray 88 advancing on conveyor 56 strikes the gate, the traveling surface of the belt 100 frictionally engages the leading end of the tray and turns it toward the side ledge conveyor 58.

In most cases it is appropriate that the drive mechanism for the side ledge conveyor 58 be normally idle, and that the same should advance only when a tray is delivered thereon. Accordingly a pair of limit switches 142 and 144 are provided to start and stop the conveyor 58. Hence when the gate 72 diverts a tray, the same will strike limit switch 142, causing the conventional drive system (not shown) for conveyor 58 to be placed in operation. Thereupon the tray is carried off on conveyor 58 to the point where it strikes the second limit switch 144, thereby stopping the conveyor 58.

The switch 144 which stops the movement of conveyor 58 may also be utilized to actuate the release mechanism for gate 72, which has been held in operated position by holding circuits in cabinet 96. To this end these circuits are connected to switch 144 through a cable 146.

Referring now to FIGS. 4, 5 and 6, it is seen that the card reader 74 includes an insulation block 160 having a plurality of spaced holes as at 162 bored therein, each adapted to receive a non-contacting metal detector probe as at 164. The block 160 may extend through a rectangular opening in the cabinet 96 and be secured thereto by means of bolts as at 166.

The block 160 is of such a length that when the base flange as at 164a of a probe as at 164 is seated at the rear of one of the bored openings in the block, the active end of the probe sits flush with the end of the block which points in the direction of a passing signal card 90.

As is shown in the sections of FIG. 5 and FIG. 6, each signal card preferably comprises three bonded laminations a, 90b and 90c of plastic or other electrically insulating material. The center lamination 90b is punched, drilled or molded with a plurality of holes as at 168 each adapted to accommodate a metal disc as at 170. It is apparent that when a card assembly passes in front of the reader 74, the presentation of a metal disc in direct alignment with one of the metal detector probes will trigger the metal detector.

It is seen that the pattern of holes as at 168 in the center lamination 90b of the card corresponds to the pat tern of the holes as at 162 in the block which accommodates the metal detector probes. In the illustrated arrangement, only two probes 164 and 172 are used in one card reader. correspondingly, only two metal discs and 174 are mounted in each signal card.

The probe 164 is connected by a flexible conductor 176 to an electronic panel 178, and similarly probe 172 is connected by a flexible conductor 180 to a duplicate electronic panel 182. Thus a probe may be easily inserted in, or removed from, the rear of any hole in the insulating block 160 for the purpose of setting up or altering the code to which the card reader 74 will respond.

Suitable circuitry for the gate control system is shown in FIG. 7, wherein it is seen that the probe 164 is con nected by conductor 176 to a metal detector circuit 178a adapted to trigger an associated relay 17812. Similiarly the probe 172 is connected by conductor 180 to a detector circuit 182a adapted to trigger a relay 18217. The relays and detector circuits are connected to a suitable power supply 184. When both metal detector relays 17% and 1821) are energized simultaneously, a conventional hold relay 186 is also energized from the power supply. Once the hold relay is energized, it will remain energized even though one or both of the metal detector relays 1781; and 182b is de-energized, due to its holding circuit from the power supply which includes contacts 144a of the limit switch 144 and conductors 146a and 146b. When the hold relay is energized, it connects the power supply 184 to the gate solenoids 136a and 138:: which actuate the fluid pressure control valves 136 and 138 shown in FIG. 2. These valves in turn control the drive cylinder 128 which aotuates the gate 72.

The operation of .the system may be summarized as follows, referring to FIGS. 2 and 7. The card reader 74 is adapted to respond only to a signal card having metal discs in both of the particular two holes shown in FIG. 6, which holes correspond to the location of the probes 164 and 172 in the insulating block 160. Cards having discs in other locations in the same horizontal rows may trigger the metal detectors independently.

However, the hold relay 186 cannot be energized by operation of either relay 17812 or 1821) alone, or by operation of both relays at different times. Hence the gate 72 will not interfere with through traffic on conveyor 56 of trays bearing signal cards adapted to trigger gates on other side ledge conveyors receiving mail to other destinations.

However, when a passing signal card has its metal discs located in position to activate both metal detectors simultaneously, both relays 178k and 18% will close their contacts at the same time, completing a circuit from the power supply 184 which energized the hold relay 186. The hold relay will then complete its holding circuit through limit switch contacts 144a and simultaneously apply power to gate solenoids 136a and 138a. Solenoid 136a will operate valve 136 so as to connect the air pressure line 140 through air hose 132 to the rod end of air cylinder 128, forcing the piston (not shown) to the rear of the cylinder and causing the piston rod 124 to retract. Simultaneously solenoid 138a will operate valve 138 so as to disconnect the air pressure line 140 from air hose 134 and to vent the hose 134 to the atmosphere, thus relieving the pressure in the closed end of cylinder 128.

The retracting operation of the drive cylinder will actuate the gate 72 as hereinabove described, diverting the tray 88 onto the conveyor 58. Operation of limit switch 142' by the tray starts the conveyor 58, which carries the tray onward until it contacts the limit switch 144. Switch 144 stops conveyor 58, and simultaneously opens its contacts 144a. Since the relays 178i) and 18211 were deenergized after the discs 170 and 174 passed the metal detector probes, the opening of switch contacts 144a deenergizes hold relay 186 which in turn de-energizes solenoids 136a and 138a. Accordingly the gate 72, which has meanwhile been held across the path of conveyor 56, is restored to its original position.

Although the invention is not limited to any particular spatial arrangement of the metal detector probes and the metallic elements to be detected thereby, it will be noted that the signal card and the block shown in FIGS. 4 and 6 are adapted to a spatial code wherein a single master column of holes is spaced some distance from a group of holes comprising a plurality of columns. One probe is always located in one hole of the master column as is illustrated by the position of probe 164, and similarly one metal disc always occupies one hole of the master column, as is illustrated by the position of disc 170. The master column is spaced from the secondary group of columns by a distance greater than the maximum width of the secondary group. Thus no combination of discs in the secondary columns alone can trigger both the master probe and a secondary probe simultaneously, as is required to operate the gate. That is to say, the signal card is read only when the master column of the signal card is in proximity to the master probe, which is a unique position of the signal card in its travel past the card reader.

The invention likewise is not limited to any particular number of metal detectors. Although only two are used in the illustrated card reader, three or more may be provided. Hence the particular embodiment of the invention shown and described is meant to be illustrative only and not restrictive, since it is obvious that many changes and modifications can be made within the spirit and scope of the invention as is set forth in the appended claims.

What is claimed is:

1. An article distribution system comprising a main conveyor bearing a series of articles to be distributed, a plurality of branch conveyors spaced along the path of said main conveyor and intersecting the same, a diverter gate at each such intersection, said gate being movable from a first position clearing the path of said articles on said main conveyor to a second position for diverting an article on said main conveyor to the intersecting branch conveyor, a non-metallic signal card carried by each of said articles, means for detachably securing said card to its associated article, a plurality of metallic elements spatially arranged on each of said signal cards in accordance with a destination-indicative coded pattern, a plurality of metal detectors each responsive to the presence of an electrical conduct-or without physical contact therewith and adapted to be triggered by proximity thereto,

means for mounting said metal detectors adjacent said intersection and spatially arranged relative thereto in accordance with a location-indicative coded pattern, guide means mounted on one side of said main conveyor and adjacent said intersection for directing the flow of said articles in spaced relation to said metal detectors, whereby said metallic elements are guided in proximity to said metal detectors without contacting the same, and means energized by synergetic action of said metal detectors on coincidence of said location-indicative pattern with said destination-indicative pattern on a passing article for actuating said gate to said second position.

2. A system as in claim 1 wherein each of said metal detectors comprises a probe unit and an electronic chassis unit, wherein said metal detector mounting means comprises a non-metallic block having a plurality of receptacles each adapted to receive said probe unit, and which includes flexible conductors connecting said chassis unit to said probe unit to permit selection and alteration of said location-indicative pattern by transferring said probe from one receptacle to another.

3. A system as in claim 1 wherein each of said signal cards comprises a lamination of non-metallic sheets, one of said sheets having a plurality of spaced apertures therein, at least two of said apertures each containing one of said metallic element-s electrically insulated from other elements on said card.

References Cited in the file of this patent UNITED STATES PATENTS 1,797,864 Harlandt Mar. 24, 1931 1,909,481 Allen May 16, 1933 2,063,230 Crady Dec. 8, 1936 2,773,658 Von Otteren et al Dec. 11, 1956 2,794,535 Hauschild et al. June 4, 1957 OTHER REFERENCES Meeh. Handling, article by Mumby, January 1958, pages 19-26.

Claims (1)

1. AN ARTICLE DISTRIBUTION SYSTEM COMPRISING A MAIN CONVEYOR BEARING A SERIES OF ARTICLES TO BE DISTRIBUTED, A PLURALITY OF BRANCH CONVEYORS SPACED ALONG THE PATH OF SAID MAIN CONVEYOR AND INTERSECTING THE SAME, A DIVERTER GATE AT EACH SUCH INTERSECTION, SAID GATE BEING MOVABLE FROM A FIRST POSITION CLEARING THE PATH OF SAID ARTICLES ON SAID MAIN CONVEYOR TO A SECOND POSITION FOR DIVERTING AN ARTICLE ON SAID MAIN CONVEYOR TO THE INTERSECTING BRANCH CONVEYOR, A NON-METALLIC SIGNAL CARD CARRIED BY EACH OF SAID ARTICLES, MEANS FOR DETACHABLY SECURING SAID CARD TO ITS ASSOCIATED ARTICLE, A PLURALITY OF METALLIC ELEMENTS SPATIALLY ARRANGED ON EACH OF SAID SIGNAL CARDS IN ACCORDANCE WITH A DESTINATION-INDICATIVE CODED PATTERN, A PLURALITY OF METAL DETECTORS EACH RESPONSIVE TO THE PRESENCE OF AN ELECTRICAL CONDUCTOR WITHOUT PHYSICAL CONTACT THEREWITH AND ADAPTED TO BE TRIGGERED BY PROXIMITY THERETO, MEANS FOR MOUNTING SAID METAL DETECTORS ADJACENT SAID INTERSECTION AND SPATIALLY ARRANGED RELATIVE THERETO IN ACCORDANCE WITH A LOCATION-INDICATIVE CODED PATTERN, GUIDE MEANS MOUNTED ON ONE SIDE OF SAID MAIN CONVEYOR AND ADJACENT SAID INTERSECTION FOR DIRECTING THE FLOW OF SAID ARTICLES IN SPACED RELATION TO SAID METAL DETECTORS, WHEREBY SAID METALLIC ELEMENTS ARE GUIDED IN PROXIMITY TO SAID METAL DETECTORS WITHOUT CONTACTING THE SAME, AND MEANS ENERGIZED BY SYNERGETIC ACTION OF SAID METAL DETECTORS ON COINCIDENCE OF SAID LOCATION-INDICATIVE PATTERN WITH SAID DESTINATION-INDICATIVE PATTERN ON A PASSING ARTICLE FOR ACTUATING SAID GATE TO SAID SECOND POSITION.

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