CA1224425A - Warehouse system with pan extractor mechanism - Google Patents

Abstract

WAREHOUSE SYSTEM WITH
PAN EXTRACTOR MECHANISM

ABSTRACT OF THE DISCLOSURE
A warehouse system employs a crane guided for movement along an aisle with storage racks on opposite sides thereof and mounting a carriage for vertical reciprocation thereon. An extractor supported on the carriage has a pair of narrow extensible arms which engage the undersides of lips formed on opposite sides of a tote pan. The extensible arms each include three rails nested in one-above-the-other relation with the intermediate rail having vertical load bearing rollers engaging the upper and lower rails. One embodiment of the invention shows a harmonic drive causing extension and retraction of the extractor arms through chain and pulley arrangements. The tote pans are nestable and have ribbed bottoms cooperatively engaging cantilevered brackets on the storage racks whereby the pans are releasably detained in their stored position in the warehouse.

Description

WAREHOUSE SYSTEM WITH
PAN EXTRACTOR MECHANISM

BACK5~0UND OF THE INVENTION
_ Technical Field This invention relates to automated warehouse systems and more particularly to small parts or mini-load storage and retrieval apparatus using tote pans, Information Disclosure Statement Heretofore others have devised small parts or mini-load warehousing systems wherein tote pans are slid into and out of rack compartments at opposite sides of an aisle by an extractor mechanism. Some such systems are disclosed in U.S. patent 3,809,259 issued May 7, 15 1974 to George R. Pipes; U.S. patent 3,8B3,008 issued May 13, 1975 to John A. Castaldi and U.S. patent 4,010,855 issued March 8, 1977 to Joseph F. Smith wherein an extractor mechanism on a crane carriage has a finger engagable with a lip or bracket at the lower 20 front portion of the tote pan to slide it into or out of a rack storage compartment at either side of an aisle.
The pan capacity of sliding ~ote pan systems currently in use is approximately 500 pounds. The problem of wear due to slidiny the tote pan has been 25 recognized and alleviated to some e~tent by ma~erial selection and provision of replaceable wear ~trips such as nylon strips 42 in before mentioned U.S. patent 3,809,259. The use of endless belts 75, 75' in before mentioned U.S. patent 3~883,008 is believed to reduce 30 wear as compared to mechanisms which slide the tote pan on and off the elevatable carriage. In U.S. patent 3,708,077 issued to Kenneth A. Richens et al on January 2, 1973, rollers 152 are used to reduce friction and attendant wear of the pan and the carriage. The 35 before mentioned U.S. patent 3,708,077 is also of interest in that it shows a tote pan extractor mechanism having a multiple rail mechanism for moving the tote pan into and out of storage in a warehouse wherein gear ~a s racks and gears are used to effect coordinated relati~e movement between the rails.
U.S. patent 3,892,324 issued July 1, 1975 to Vincent R. Faletti, Jr. shows a three section extractor mechanism wherein movement of the top section relative to the intermediate section is controlled by a cable and pulley arrangement and movement of the intermediate section relative to the base section is controlled by gears on the base section engaging a gear rack on the intermediate section. U.S. patent 3,881,424 issued May 6, 1975 to Harry W. Thompson and Canadian patent 826,501 issued November 4, 1969 to Weston R. Loomer each shows a pair of extensible and retractable load support mechanisms each of which includes a load support bar carrying rollers engaging a pair of intermediate support rails which in turn are supported by rollers on the lift platform. Relative reciprocating movement between the load support bar and the intermediate rails is effected by gear racks on the load support bar and the lift platform engaged by spur gears rotatably supported by the intermediate support rails and drive gears on the lift platform engaging a gear rack on one of the intermediate support rails7 The prior art harmonic drive for an extractor mechanism illustrated in Figs. 15-17, uses four pairs of parallel bars which are cooperatively engaged by a pair of cam rollers on a drive wheel to move loads from the hoist to a first or second position in a rack compartment of the type suitable for receiving two loads. Rotation of the drive wheel 180 in one direction from the ~load on hoist~ position shown in Figs. 15 and 16 causes extension of the shiftable load support arms to a ~first load in racks~ position showing in Fig. 17. A
further 180 rotation of the drive wheel in the same direction extends the shuttle support to place the load in the ~second load in racks~ posit~on shown in Fig. 17.

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BRI_SUMMARY OF THE INVENTION
An automatic storage and retrieval system is provided in which a crane with an elevatable carriage carrying a pan extractor mechanism is movable fore and aft along an aisle having storage racks on each side thereof defining a plurality of vertical storage compartments. A plurality of storage pans placed in the storage compartments each have rigidly interconnected bottom and side walls with a pair of opposed side walls presenting a pair of generally horizontal outward flaring lips of predetermined width extending in length along the upper parts of the opposed pdir of side walls in transverse relation to the aisle. The extractor mechanis~ includes a pair of extensible and retractable horizontal arms mounted on the carriage parallel to one . ,: ~.\

another and transverse to the aisle. The arms are extensible for engagement with the underside of the lips of a storage pan in a selected one of the storage rack compartments upon raising of the carriage. The arms are subsequently retracted to transport the selected storage pan to a storage position on the carriage wherein the crane and carriage may be moved along the aisle without interference with the racks and the pans stored therein.
Thus, the tote pan is lifted off the racks before 10 extraction and carried by the extractor arms, thereby reducing sliding wear and operating forces as compared to prior art sliding pan extractors.
Since the tote pan is supported on the parallel extractor arms during insertion in and 15 extraction from the storage compartment, the tote pan bottom is not subjected ~o sliding wear during such operations. Additionally, the use of an extractor having narrow support arms engaging lips on the tote pan sides permits more efficient use of available space in 20 the storage facilityO
In the preferred embodiment of the invention a harmonic drive is used to provide desired acceleration and deceleration at the beginning and ending of the side shifting movement of the extractor arms. The harmonic 25 drive reciprocates a shuttle carrying pulleys engaged by chains, the opposite ends of which are connected to a stationary base rail and an intermediate rail o an extractor arm to effect shifting movement of the latter at a 2 to 1 ratio to shiftins movement of the shuttleO
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated in ~he drawings in which:
Fig~ 1 is a pictorial view of a crane supported for movement along an aisle of an automated 35 warehouse and including a carriage on which an extractor i5 mounted;

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Fig. 2 is a pictorial view of the extractor shown in Fig. 1 out wherein the extractor arms are partially extended;
Fig. 3 is a front view of the extractor with the extractor arms in a nonextended condition;
Fig. 4 is a partial view of the extractor showing the extractor arms in their extend~d positions and engaging the undersides of lips on opposite sides of a storage pan;
FigO 5 is a view taken along the line V-V in Fig. 3;
Fig. 6 is a top view of the extractor with the support arms shown in an e~tended position and with parts broken away for illustration purposes;
Fig. 7 is a view taken along the line VII-VII
in FigO 3;
Fig. 8 is a top view of the carriage and extractor;
Fig. 9 is a view taken along the line IX-IX in Fig. 8;
Fig. 10 is an end view of an aisle of a warehouse in which the crane of Fig. 1 operates;
Fig. 11 is a view taken on the line XI-XI in Fig. 10;
Fig. 12 is an exploded pictorial view of a combination of a tote pan and an extender therefor;
Fig~ 13 is a view taken along the line XIII-XIII in Fig. 12;
Fig. 14 is a pictorial view of an al~ernate construction for the pan extractor; and Figs. 15-17 illustrate a prior art extractor mechanism.
DETAILED DESCR ~
Referring to the drawings, a small parts warehousing system of the present invention may utilize an automatic storage and retrieval vehicle such as the illustrated computer controlled crane 21 which carries suitable rollers 22 at the top thereof for engaging an ; ~ ~
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overhead track 23 and a pair of double flanged wheels 24 vertically engaging a bottom track 26 in the aisle of a , ~

warehouse, as illustrated in Figs. 10 and 11. As illustrated in Figs. 1 and 8, a carriage 31 is reciprocatingly mounted on a mast 32 of the crane 21 by a plurality of rollers 33. The carriage 31, which is raised and lowered on the mast 32 by a cable 30, carries an extractor 34 having a support structure 36 rigidly secured to and extending horizontally forward from the carriaye 31. The support structure 36 includes a pair of horizontal parallel tracks 37, 38 rigidly secured, as 10 by welding, to a longitudinal box frame 40 of the support structure 36 and extending in transverse relation to the aisle terminating in mounting pads 44l welded to their ends. The mounting pads 44' are in turn welded to the upright flanges of a pair of angles 39, 41 15 at transversely opposite sides of the extractor.
Horizontal flanges 42~ 43 of the angles 39, 41 are in supporting relation to a pair of parallel base rails 51, 52 of a pair of extensible and retractable extractor arms or arm structures 53, $4. The rails 51, 52 have 20 reinforcing bars 44, 45 secured to their inner sides by screws 46. The reinforcing bars 44, 45 have upwardly diverging surfaces 47, 48 to assist in guiding a tote pan into proper supported position on the arms 53, 54 should any misalignment occur. The rails 51, 52 and 25 their reinforcing bars 44, 45 are rigidly secured to the flanges 42, 43 by cap screws 49~ 50.
Referring to Figs. 2 through 9, the arm structures 53, 54 are d.isposed in parallel relation to one another and at substantially the same elevation.
30 The arm structures 53, 54 are relatively narrow in the longitudinal direction of the aisle and reciprocate horizontally in transverse relation to the aisle between a nonextended or nested position, as shown in Figs. 1 and 3, and an extended position into a rack storage 35 compartment at one side o~ the aisle as illustrated in Fig. 4. Referring specifically to the arm structure 54, the base rail 52 supports an intermediate rail 56 which in turn supports a pan support rail 57 disposed vertically above and spaced from base rail 52. The pan support rail 57 has an upward facing convex surface 58 which is complementary to and adapted to engage the down-wardly facing concave underside surface 61 of a lip 62 extending along a side or side wall 63 of a tote pan 64.
The lip 62 forms part of the top rim of the pan 64 and extends substantially coextensively along the length of the side wall 63, which side is disposed transverse to the aisle when it is in a storage compartment in the 10 racks at one of the opposite sides of the aisle and also when the pan is transported by the crane 21.
The pan 64, as illustrated in Figs. 4, 5, 9, 12 and 13, is molded in a single piece whereby its bottom 71 is integral with its end walls 72, 73 and side 15 walls 63, 74. The l.ips 62, 76 flare outwardly from the upper end of the side walls 63, 74 and include raised ribs 77, 77' presenting downwardly facing cavities or pockets 78, 78'. Two of the downwardly open pockets 78, 78' on each lip register with upwardly extending 20 projections 81, 81', respectivelyl on the pan support arms 53, 54. The ribs 77, 77' on the pan lips 62, 76 not only serve to provide cavities 78, 78' nesting with the projections 81, ~l' to releasably retain the pan 64 on the extractor but also serve as reinforcing structure 25 for the lips 62, 76. While only three ribs are shown on each of the lips, additional reinforcement of the lips is achievable by adding additional ribs at selected points along the length of the lip5 62, 76. The side walls 63, 74 of the pan 64 are strengthened by shoulders 30 75, 80 which also serve as upport ledges when the pans are stacked one within the other.
The pan bottom 71 has a corrugated configura-tion with the alternate ridges and grooves extending parallel to the end walls 72, 73 and in transverse 35 relation to the side walls 63, 74 and the lips 62, 76.
The corrugated configurations provides a strong bottom having low deflection, as compared to a flat bottom of the same thickness o material. As shown in Fig. 4, two of the downward facing recesses 82, 83 in the pan bottom register with and engage front and rear support brackets 84, 86 on the rack uprights 87, 88 to releasably lock the pan in its stored position in a storage compartment defined by the vertical spacing of ~he support brackets.
As also shown in Fig. 11, the brackets 84, 86 are horizontal bars welded at an intermediate portion thereof to the uprights. Cantilevered ends of the bars extend parallel to the aisle a relatively short distance 10 toward the adjacent upright. In those instances where longitudinal braces 89 extend between the aisle uprights 87, the braces serve to support the tote pan thus replacing the support brackets 84.
As shown in Fig. 12, an extender 90 may be 15 inserted in and secured to the pan to provide a plurality of storage cells in a single pan. The extender 90 increases the volumetric capacity of the pan thus making it particularly suited to storing a pl~rality of segregated lightweight items.
The intermediate rail 56 of the extensible arm 52 includes an upright plate or beam 91 which is relatively narrow in the horizontal direction of the aisle, that is, in the fore and aft direction. The beam 91 has upper and lower portions in juxtaposed, lapped 25 relation to the pan support rail 57 and the base rail 52. In the nested or nonextended condition of the extractor, as shown in Figs. 1, 3 and 8, the rails 52, 56, 57 are coextensive with the support 36. As shown in Fig. 7, the intermediate rail 56 includes a spacer bar 30 part 92 sandwiched between and secured to the beam 91 and a guide plate 93 by releasable fastening means in the form of bolts 96 and flat head screws 97 in threaded engagement with drilled and tapped openings in the bolts 96. In order to maintain an aligned relationship of the 35 rails 57, 56, 52, the plate 93 presents guide parts or tapered slide or bearing surfaces 98, 99 in horizontal thrust transmitting relation to confronting and complementary slide surfaces 98', 99', on the pan support rail 57 and base rail 52 and the upper and lower portions of the beam 91 present flat vertical surfaces 100, 105 in horizontal thrust transmitting relation to flat vertical confronting slide surfaces 100', 105' on the pan support and base rails 57, 52.
Referring also to Figs. 3, 5 and 9, the pan support rail 57 includes wall means defining a horizontal groove 101 having upper and lower horizon'al bearing surfaces 102, 103 vertically facing one another 10 and a vertical interior surface 104 facing in a forward horizontal direction. The base rail 52 includes wall means defining a horizontal groove 106 parallel to groove 101 of the pan support rail 57 which presents upper and lower horizontal bearing surfaces 107, 108 in 15 vertical facing relation to one another and a vertical interior surface 109 facing horizontally forward. Thus, both grooves 101 and 106 are open in the forward direction of movement of the crane 217 A plurality of upper rollers 111 are rotatably mounted on axles 112 20 and 120 which are secured to the upper poxtion or part of the beam 91 for rotation about the parallel horizontal axes 114 of the axles 112 extending in the horizontal direction of the aisle traversed by the crane 21. The upper rollers 111 are operatively disposed 25 within the groove 101 and are in rolling, vertical load bearing engagement with the bearing surfaces 102, 103 of the pan support rail 57 thus serving to support the latter as it is horizontally reciprocated relative to the intermediate rail 56. The intermediate rail 56 30 rotatably carries lower rollers 116 on horizontally spaced parallel axes 117, such rollers being in rolling vertical load bearing engagement with ~he upper and lower bearing surfaces 107, 108 of the groove 106 of the base rail 52 whereby the intermediate rail 56 is 35 vertically supported on the base rail 520 The lower rollers 116 are rotatably mounted on a lower part of the beam by axles 113 and 125 mounted on the beam 91.
Rollers 111' and 116' are similarly mounted on an 9 ~ 5 intermediate rail 56' of extensible arm 53 and cooperate with grooves 101l and 106i in a pan support rail 57' and the base rail 51. The axles 112 and 118 for the rollers 111, 111', 116, 116' on the portion of the beams adjacent the reinforcing structures 182, 182' are threaded to receive nuts 113, 119. The other axles 120, 125 are riveted to the beams 91, 91'.
The pan support arm 57 is caused to move lengthwise relative to the intermediate rail 56 by a 10 chain and pulley mechanism including a pair of pulleys 121, 122 rotatably mounted on opposite end portions of the intermediate rail 56 on horizontal, parallel axes 121', 122' extending transverse to the direction of move-ment of the intermediate rail 56 and a pair of flexible 15 motion transmitting elements in the form of chains 123, 124 having intermediate portions reeved, respectively, about the pulleys 121~ 122. The opposite ends of the chain 123 are secured to corresponding ends of the pan support rail 57 and the base rail 52 at one side of the 20 extractor by anchors 126, 127, respectively, and the opposite ends of the chain 124 are secured to correspond-ing ends of the pan support rail 57 and the base rail 52 at the opposite side of the extractor by a pair of anchors 131, 132, respec~ively.
As illustrated in Figs. 3, 5 and 7, the pulley 121 is rotatably mounted on stub shaft 136 formed on a slide member 137 with the free end of the shaft 136 confronting the inner side of the beam 91. The slide member 137 includes a pair of aligned longitudinal slots 30 138, 139 in sliding engagement with a pair of spacer bushings 141, 142 through which a pair of bolts 96 extend. Thus, the spacer bushings 141, 142 serve to guide the lengthwise movement of the slide member 137 and to space the beam 91 and plate 93 of the inter-35 mediate rail 56 relative to one another. The pulley 121and th~ slide member 137 on which it is mounted may be ad~usted in the lengthwise direction of the intermediate rail 56 by turning an adjustment member in the form of a screw 144. The adjustment screw 144 includes a threaded portion 146 on one end in threaded engagement with a drilled and tapped opening 147 in the spacer bar part 92 of the intermediate rail 56. An exteriorly splined wheel 148 integrally formed on the screw 144 inter-mediate its length can be turned by the prying action of a screwdriver, or other prying tool, inserted through an elongated access opening 149 in the guide plate 93.
Biasing means in the form of belleville washers 151 are 10 interposed between the wheel 148 of the screw 144 and the end of ~he slide member 137 with an end 152 of the screw extending loosely into an aligned bore 153 in the slide member 137. As shown in Fig. 3, a slide member 156, similar to the slide member 137, and an adjusting 15 screw 157 are provided for pulley 122 at the other end of the intermediate rail 56. The slide member 156 is positioned so the free end of its stub shaf~ 158 is in confronting relation to the guide plate 93, thereby placing the pulley 122 adjacent the plate 93. The 20 offset positioning of the pulleys 121, 122 and the chain anchors place the chains 123, 124 in side-by-side relation to one another without interference. As shown in Figs. 5, 7 and 9, the chains 123, 124 extend through l1pper and lower passageways 161, 162 between the bottom 25 of the pan support rail 57 and the central spacer part 92 and between the latter and the top of the base rail 520 In the nonextended condition of the extractor, the pan support rail 57 can be centered on ~made transversely coextensive with) the intermediate rail 56, 30 when the latter is centered on the base rail~ by turning the adjusting screws 144, 157. The screws 144, 157 may also be turned to adjust the tension of the chains 123, 12~.
A similar chain and pulley arrangement is 35 provided for the ex~ractor arm 53 to effect shifting movement of pan support rail S7lo Reerring to Figs. 1, 2, 3, 4, 5, 6, S and 9, a chain and cable side shift mechanism 166 is provided

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for lengthwise extension of the intermediate rail 56 relative to the base rail 52, which movement is transverse to the aisle in which the crane 21 is operating. The side shift mechanism 166 includes a shuttle 167 reciprocatingly mounted on the tracks 37, 38 and rotatably carrying pulleys 168, 169 on its front end and pulleys 171, 172 on its rear or aft end. The side shift mechanism 166 also includes chains 173, 174 reeved about the pulleys 168, 169, respec~ively, and chains 10 176, 177 reeved about the pulleys 171, 172, respectively. One end of chain 174 is connected to a threaded fastener 178 which in turn is adjustably connected to the channel 33 at one side of the extractor by nuts 179. The other end of the chain 174 is secured 15 by a fastener 181 to one end of a beam reinforcing structure 182 which is secured to the outer side of the beam ~1 and extends alon~ only an intermediate portion of the beam 91. One end of the chain 173 is adjustably connected to the channel 41 by a threaded fastener 183 20 and nuts 184 and the other end of the chain 173 is secured by a fastener 186 to the other end of the reinforcing structure 182. The chains 176, 177 are similarly fastened at the aft end of the extractor~ The reinforcing structure 182 is made up of two channels 25 187, 188 with lapped flanges secured by bolts 191 and nuts 192. The channel 188 is secured to the beam 91, the spacer bar 92 and the guide plate 93 by bolts 193 and nuts 194. The channel 188 is also secured to the beam 91 by the.threaded axles 112, 118 and nuts 113, 30 119. h reinforcing s~ructure 182~ includes channels 187', 188i interconnected by bolts 191 and nuts 192 with channel 188' being rigidly secured to the beam 91'. The reinforcing structures 182, 182' serve to reinforce the intermediate rails 56, 56' and their opposite ends serve 35 as anchor points for the ends of chains 173, 174 and 176~ 177. When the extractor is extended into a storage compartment for pan depositing or pan retrieval purposes as illustrated in Fig. 4, the end of the reinforcing structure 182 confronts but stops shor~ of the rack upright 87.
The shut~le 167 inc~udes a flat plate 201 to which downwardly extending roller supporting brackets 202, 203, 204, 206 are rigidly secured as by welding.
Each of the transversely spaced brackets 202, 203 at the front end of the plate ~01 includes an upper guide component in the form of a roller 208 in downward rolling thrust transmitting engagement with the top, 10 upward faclng horizontal surface 209 of the track 38 and a bottom guide component in the form of a roller 211 in upward confEonting relation to a downward facing horizontal surface 212 on the underside of the track 38.
The rollers 208, 211 are identical and have threaded 15 stub shafts 213, which are disposed on parallel horizontal axes and are ~ecured to the brackets 202, 203 by nuts 214. The transversely spaced brackets 204, 206 at the rear end of the plate 201 are reverse images of one another and each rotatably support an upper guide 20 component or roller 216 in vertical thrust transmitting relation and rolling engagement with an upward facing horizontal surface 217 on the top of the track 37 and a bottom guide component or roller 218 in upward thrust transmitting relation to a downward facing horizontal 25 surface 219 on the underside of the track 37. The brackets 204, 206 also rotatably support fore and aft guide components in the form of horizontal thrust transmitting roller 221, 222 in horizontal confronting relation to parallel vertical surfaces 223, 224 on the 30 fore and aft sides of the track 37. The upper and lower guide components or rollers 216, 218 guide the shuttle horizontally on the track 37 preventing relative vertical displacement between the plate 201 and the track 37 and the upper and lower guide components or 35 rollers 208, 211 guide the shuttle transversely to the fore and aft direction of movement of the crane to prevent relative displacement between the plate 201 and the track 37 in the fore and aft direction of the aisle.

Thus, the rollers 216, 218, 221, 222 guide the shuttle 157 horizontally and transversely on the bearing surfaces 217, 219, 223, 224 of the rear track 37 and the shuttle 167 is guided only horizontally on the fron~
track 38 since fore and aft guide rollers are not provided at the front track 38.
Side shift movement of the shuttle 167 on its tracks 37, 38 is effected by power operated means including a harmonic extrac~or drive which includes a 10 driver lever 131 whose central hub 132 is nonrotatably secured ~o a vertical shaft 133 rotatably mounted on the support structure 40 of the carriage 31 on a vertical axis 134 by flange bearings 136l 137 bolted to the top and bottom plates 13B, 139 of the support structure 40 15 by bolts 141 and nuts 142. The driver lever 131 carries a pair of horizontal thrust transmitting elements in the form of rollers 143, 144 rotatably mounted on vertical axes on the upper outer opposite ends of the lever 131 at e~ual distances (radii) from the axis 134. In the 20 retracted condition of the extractor as shown in FigsD 8 and 9, the rollers 143, 144 are disposed in the forward ends of the fore and aft extending and downwardly open grooves defined by the parallel and transversely spaced cam bars 146, 147, 148, 149 rigidly secured to the 25 underside of the plate 201 by screws 151. The cam bars 146, 147, 148, 149 are tapered slightly at their front ends to provide a flared opening at the front end of each groove to facilitate entrance and exit of the rollers 143, 144 from the grooves formed by the cam bars 30 146-149. A large diameter sprocket 152 and a small diameter sprocket 153 are nonrotatably secured to the vertical shaft 133. The large diameter sprocket 152 is connected in driven relation to a reversible electric motor 154 by an output or drive sprocket 156 driven by 35 the motor 154 mounted on the carriage 31 and an endless drive chain 157 operatiYely reeved about sprockets 156 and 152.

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OPERATION
~ hen the shaft 133 is rotated clockwise 180g about its vertical axis 134, as viewed in FigO 8, the roller 143 will bear against cam bar 147 causing the shuttle to move transversely on the tracks 37, 38 to the position shown in Fig. 6 wherein the arms 53, 54 are fully extended at one side of the aisleO At this point the motor i5 automatically stopped by a control 161 mounted on ~he carriage 31 which includes a sprocket 162 10 operatively connected to the shaft 133 by a timing chain 163 which is reeved about the sprockets 162 and 153, as is illustrated in Fig~ 8. When the shaft 133 is rotated 180 in the opposite direction from its transport position shown in Fig. 8, the shuttle 167 will be 15 shifted in the opposite transverse direction to fully extend the pan support arms 53, 54 into a storage compartment at the opposite side of the aisle.
For every inch the shuttle 167 moves on the tracks 37, 38, the intermediate rails 56, 56' will 20 simultaneously move two inches, and the pan support rails 56, 56' will move four inches in the same direction as the shuttle moves.
When extracting a pan 64 Erom a storage compartment in a rack structure, the crane and carriage 25 are positioned so that upon extension of the arms 53, 54 they will be beneath the lips of the selected pan. Upon raising the carriage 31 a short distance, the rails 56, 56' of the arms 54, 53 will engage the underside of the lips 62, 76 and the pan will be raised from the support 30 bars 84 a sufficient distance so that the pan bottom will clear the support bars 84 during retraction of the arms and pan from the storage compartment. Registration of the rib cavities 78, 78' with the projections 81, 81' prevents relative movement between the pan 64 and the 35 pan support rails 56, 56' during a storage or extraction operation or during transport of the pan by the crane.
An alternate extractor 301 is illustrated in Fig. 14 wherein a reversible electric drive motor 302 - 15 ~
and a pair of extensible and contractible pan support arms 303, 304 are mounted on a support structure extending forwardly from a carriage 307. The support structure includes a pair of horizontal forks 308, 309 rigidly secured, as by welding, at their rear ends to the carriage 307. An L-shaped bracket 311 has a vertical leg welded to the arm 308 and the motor 302 is releasably secured ~o the horizontal leg of the bracket 311 by cap screws 312. Referring to the arm 304, a pan 10 support rail 315 is supported on an intermediate rail 317 by vertical load bearing engagement between a set of upper horizontally spaced rollers 318 on the inter mediate support and the upper and lower surfaces of a forwardly open groove 319 in the pan support rail 316.
15 The intermediate rail 317 is supported on a base rail 321 of arm 304 by vertical load bearing engagement between lower horizontally spaced rollers 322 on the intermediate rail 317 and the top and bottom surfaces of a forwardly open groove 323 in base rail 321. The arm 20 303 is a reverse image of arm 304 with an intermediate rail 324 carrying rollers 326 engaging groove 327 in pan support rail 328 and lower rollers, not shown, engaging a groove 329 in a ~ase rail 331. A combined base rail reinforcing member and pan guide in the ~orm of bar 332 25 is secured to the front of base rail 331 and presents tapered edges 333, 334 at its opposite ends. A similar bar, not shown, is secured to the rear side of base rail 321. Relative transverse shifting of the pan support rail 328 of the arm 303 relative to the intermediate 30 rail 324 is effected by a plurality of transversely spaced spur gears 336 meshing with a rack gear 337 on the bottom of the pan support rail 328 and a rack gear 338 on the top of base rail 331. The gears 336 are rotatably supported on shafts 339 mounted at their 35 opposite ends in a beam part 340 and a guide part 343 of ~he intermediate rail 3240 Similarly a plurality of transversely spaced spur gears~ not shown, are carried by shafts, not shown, whose ends are supported on a beam - 16 ~
part 344 and a guide part 345 of the intermediate rail 317 of the arm 304 and mesh with gear racks 341, 342 on the rails 316 and 321 of the extensible arm 304. The power operated means for side shifting the extractor arms 303, 304 includes the reversible electric motor 302 having a through shaft 346 to which a pair of double flanged drive sprockets 347, 348 are secured by keys for rotation therewith and a pair of endless double cog belts 351, 352 driven by the sprockets 347, 348. Belt 10 352 is reeved about an idler pulley 353 and its upper run is maintained substantially horizontal by support rollers 354, 356, 357. An idler tensioning roller 358 engages the lower run of the belt 352. Support rollers 354, 357 are rotatably mounted on the ends of the forks 15 308l 309, respectiYely, and support roller 356 is rotatably supported on the base rail 321 by a bracket 361. The idler roller 353 is al50 rotatably supported on the base rail 321 by a bracket, which is not shown, but which is a reverse image of a bracket 362 supporting 20 the stub shaft 363 on which an idler pulley~ not shown, for belt 351 is mounted. ~he tensioning pulley 358 is adjustably mounted on a bracket 364 depending from the front end of the fork 303. The outside cogs of the upper run of the belt 352 mesh with the teeth of a rack 25 gear 366 on a central reinforcing section or part 367 of the intermediate rail 317 of the extensible arm 304.
Similarly a rack ~ear, not shown, on a reinforcing part 368 of the intermediate rail 324 of the extensible arm 303 meshes with the teeth or cogs on the upper run of 30 the drive belt 351 The drive belt 351 i5 supported in its upper run by a support roller 371 rotatably mounted on a bracket 372 welded to the underside of the base rail 331. A low friction replaceable wear pad 373 is releasably secured to the top side of the fork 308 below 35 the upper run of the belt 351 and a similar wear pad, now shown, is fastened to the top side of the fork 309 in upward confronting relation to the underside of ~he upper run of the belt 351. The wear pads, which may be made of a low friction high density plastic, serve to maintain engagement of the upper run of the belt 351 with the gear rack, not shown, on the intermediate rail 324.
During operation, clockwise rotation of the motor shaft 346 causes the upper run of the belt 352 to move to the right toward one side of the extractor thereby causing the intermediate rail 317 to also move in that direction. The gears, not shown, on the intermediate rail 317 cause the pan support rail 316 to move twice the distance in the same direction relative to the base rail 321 as the intermediate rail 317 is moved relative to the base rail 321~ When the extractor 301 has been extended in such one direction to the position illustrated, automatic controls, not shown, will stop the motor and after a preprogrammed lifting or lowering of the carriage 307 for a pan extraction or a pan depositing function, the motor will be reversed and the extractor contracted to nonextended condition wherein the extractor and any pan thereon will not interfere with the racks and pans stored in the racks when the extractor is transported down the aisle by the crane, not shown, on which the carriage 307 is mounted.
DESCRIPTION OF PRIOR ART
The prior art extractor mechanism illustrated in Figs~ 15-17 includes a base frame 401 having a pair of base rails 402, 403 interconnected by a base plate 404.
Rollers 406, 407 support the rails 408~ 409 of a first intermediate shuttle section 411 for horizontal reciprocating movement. Rollers 416, 417 on rails 418, 419 of a second intermediate shuttle section 421 engage horizontal grooves in rails 408, 409 to permit relative horizontal reciprocation between shuttle sections 411 and 421. Rails 426, 427 of a third intermediate shuttle 428 are reciprocatingly carried on rollers 4~9, 431 mounted on the rails 418, 419 and a load platform 436 is supported through rollers 4371 438 on rails 441, 442 of the platform 436 cooperating with laterally inner grooves in the I-section rails 426, 427 of shuttle section 428.
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s The rails 408 and 409 are interconnected by a horizontal plate 444 to which a pair of pulleys 446, 447 and four sets of parallel bars 448, 449, 451, 452, 453, 454, 456, 457 are secured. When the bars are engaged by one of the two cam rollers 461, 462 on an operating disc 463, the shuttle section 411 ~ill be shifted laterally relative to the hoist on which the extractor mechanism is carried. The disc 463 is secured to a shaft 466 to which a pair of sprockets 467, 468 are secured. The sprocket 467 is driven by an electric motor 471 through a gear-type speed reducer 472 having an output shaft carrying a drive sprocket 473 connected to sprocket 467 by an endless drive chain 474. The sprocket 468 drives a timing mechanism 476 through a timing chain 477.
Referring particularly to Fig. 16, when the disc 463 is rotated clockwise 180~, the bars 451, 452 will be moved to the position occupied by rails 453, 454 and camming roller 462 will enter between rails 448 and 449 which will have moved to the position of rails 451, 452 illustrated in Fig. 16. In this condition of side shifting, the load on the platform 436 will be shifted to the ~first load in racks~ position as illustrated in Fig.
17. If a second 180 of clockwise rotation is imparted to the disc 463, the camming roller 462 will move the bars 448, 449 to the position occupied by bars 453, 454 in Fig. 16. In this condition of side shifted adjustment, the load will be in the ~second load in racks" position illustrates in Fig. 17. It should be understood that counterclockwise rotation of the operating disc 463 causes the shuttle to extend in the opposite lateral direction whereby loads may be stored in or retrieved from rack compartments on both sides of the aisle of the storage facility.

Claims (6)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In an automated storage and retrieval system including a crane movable fore and aft along an aisle with horizontal storage racks on each side thereof defining a plurality of vertical storage compartments therealong and a carriage elevatable on said crane, the combination comprising:
a plurality of storage pans for storable material positionable in said storage compartments, each of said pans having rigidly interconnected bottom and side walls, a pair of opposed side walls presenting a pair of generally horizontal outward flaring lips of predetermined width extending in length along the upper parts of said pair of side walls in transverse relation to said aisle, and an extractor mechanism including a pair of extensible and retractable horizontal arms mounted on said carriage parallel to one another and transverse to said aisle, said arms being extensible along the outer sides of said pair of opposed side walls and having upward facing surfaces adapted for engagement with the underside of said lips of a selected storage pan in a selected one of said compartments upon raising of said carriage and said arms being subsequently retractable to transport said selected storage pan to a transport position on said carriage wherein said pan is nested between said arms and said crane and carriage may be moved along said aisle without interference with said racks.

2. The system of claim 1 wherein said arms are relatively narrow in the horizontal direction of said aisle and each comprise relatively reciprocable rails juxtaposed in a one-above-the-other relation to one another.

3. The system of claim 2 wherein each of said arms includes a base rail fixed to said carriage, a pan support rail disposed vertically above and spaced from said base rail and an intermediate rail having a part disposed vertically between said base and pan support rails and presenting guide surfaces at horizontally opposite sides of said base and pan support rails operable to maintain vertical alignment of said rails.

4. The system of claim 3 and further comprising load supporting bearing means operatively interposed between said rails permitting said intermediate rails to reciprocate from nested positions on said base rails to extended positions relative to the latter at either side of said carriage and permitting said pan support rails to reciprocate from nested positions on said intermediate rails to extended positions relative to the latter at either side of said carriage.

5. The system of claim 1 wherein said lips of said pans have downward facing concave surfaces on their undersides and said arms have convex upward facing convex surfaces engageable with and generally complementary to said concave surfaces.

6. The system of claim 5 wherein a plurality of raised ribs are formed on each of said lips in spaced relation to one another along the length of the lips, the underside of said ribs presenting downwardly open pockets and wherein said arms include spaced projections extending upwardly from said convex surfaces in registerable relation to said pockets.