[1]Un*ited States Patent Office 3@420,389 3,420,389 AUTONIATIC LOCKING MECHANISM FOR A ROTARY LOAD CARRIER IN A STORAGE SYSTEM Stanley J. Gustetic, Euclid, Charles B. Boytz, Garrettsville, 5 and Heniy Engel, Euclid, Oh;o, assignors to The Euclid Crane and Hoist Company, Cleveland, Ohio, a corporation of Ohio Filed Sept. 29, 1966, Ser. No. 532,997 U.S. Cl. 214-16.4 9 Claims 10 Int. Cl. B65g 1/00 ABSTRACT OF TI-IE DISCLOSURE A load carrier having an extractor mechanism rotatable 15 about a generally vertical exis, with the extractor mechanism bein- adapted to insert loads into and remove loads from 2@n associated storage frame disposed alongside a travel zone in which the load carrier is movable, and with the extractor mechanism being adapted to move 20 laterally into and from the storage frame, together with clamping means for locking the extractor mechanism in parallel extending relationship with respect to the direction of extension of the travel zone, so that the extractor will be properly positioned with respect to load supporting 2 5 means of the storage frame. This invention relates in general to an automatic warehous ing system or load handling apparatus for storing 30 articl es, and more particularly relates to a clamping mec hanism for use with a movable load carrier of the syste m, for locking the load carrier in predetermined posit ion with respect -to the storage frame of the system. In United States Patent 3,268,097, issued Aug. 23, 1966, 35 in the name of Stewart F. Armington et al. and entitled, Stac ker Crane, there is disclosed an automatic warehousing system including a movable load carrier in the form of a stacker crane, of the general type with which the 40 insta nt invention may be used. Such load carrier of the afor esaid patent is supported on a pair of rails disposed paral lel with a travel zone or aisle adjacent to a storage fram e, with the load carrier being adapted to travel both hori zontally and vertically in the aisle and to deposit 45 and retrieve loads or articles from the storage frame. The load carrier of said patent includes an extractor mechanis m comprising a laterally movable carriage and a canti lever-like load supporting means in the form of an extr actor fork, affached to the carriage for supporting 50 a load and moving the load into or from the storage fram e. The extractor mechanism in tum is mounted for rotati on about a generally vertically extending axis, so that it can be moved to opposite sides of the load carrier, thus providing for the insertion and/or the retraction of 55 load s on both sides of the aisle. The present invention provides novel mechanism for use with the load carrier, for lockin.- the extractor mechanis m and more particularly the load supporting means ther eof, in parallel relation with the respect to the aisle, 60 so that the extractor fork will be in parallel aligned relations hip with respect to the storage frame during its lateral movement to deposit a load into or remove a load from the storage frame. This parallel alignment of the extr actor fork with respect to the storage frame ensures 65 that no interference will occur between the extractor fork and the storage frame during the movement of the extractor toward and from the storage frame, and thus ensures trou ble-free pickup and deposit of loads into or from the stora ge frame and proper positioning of the loads in the 70 stora ge -frame. Acc,ordingly, an object of the invention is to provide Patented Jan. 7, 1969 2 a novel load handling apparatus including a load carrier and storage mechanism, and which includes means for locking the apparatus in predetermined position with respect to the storage mechanism. Another object of the invention is to provide a load handling apparatus which includes a load carrier having an extractor mechanism rotatable about a geiierally vertical axis, with the extractor mechanism being adapted -to insert loads into and remove loads from an associated storage frame disposed alongside a travel zone in which the load carrier is movable, and with the extractor mechanism being adapted to move laterally into and from the storaae frame, together with clamping means for - locking the extractor mechanism in parallel extending relationsbip with respect to the direction of "tension of the travel zone, so that the extractor will be properly positioned with respect to load supporting means of the storage frame. A ftirther object of the invention is to provide a clamping mechanism of the latter mentioned type which includes a fluid power actuated motor unit which is automatical-ly actuated upon movement of the extractor into generally confronting relationship with respect to the storage frame for actuatin.- the clamping mechanism, and which includes means for automatically actuating the fluid motor unit to deactuate the clamping mechanism upon the initiation of rotational movement of the extractor mechanism about its generally vertical axis. A still further object of the invention is to provi,4e a load handling apparatus including a load carri6r movable in a travei zone alongside a storage frame, with the load carrier comprising an extractor mechanism rotatable by means of a motor unit about a generally vertical axis so that the extractor mechanism can be selectively rotated into a confronting position with respect to the stora.ac frame and selectively rotated away from such confronting position, with the extractor mechanism being adapted to insert loads into and remove loads from the storage frame, and with there being clamping mechanism provided for locking the extractor mechanism in paral]ei extending relationship with respect to the direction of extension of the travel zone, and with respect to the confronting storage frame, and with such clamping mechanism including a hydraulically powered reciprocal type motor unit and various controls for the motor unit, so that the motor unit is automatically actuated to clamp the extractor mechanism in said parallel extending relationship with respect to the storage frame and the travel zone upon rotation of the extractor mechanism into said confronting position, and wherein there is provided means for automatically actliating the hydraulic motor unit to cause deactuation of the clamping mechanism upon initiation of actuatioi of the motor unit controlling rotation of the extractor anvay from its confronting relationship with respect to the storage frame. Other objects and advanta,-es of the invention will be apparent from the following description take-n in conjunction with the accompanying drawings wherein: FIGURE I is a generally diagrammatic and elevational view of a load handling and storage mechanism embodyin.- the instant invention; FIGURE 2 is an enlarged, perspective, fragmentary vicw of the vertically movable hoist carriage of the load handlin.-- mechanism, and showing the extractor in an operative position wherein it extends parallel to the direet,,on of extz-,nsion of the travel zone and in confrontin.relat:@on to the storage frame of the system, and i]Iustratiii,a the clam,ping mechanism mounted on the hoist carria-.e disposed in clamping condition, so as to lock the extractor mechanism in said parallel relationship-- FIGURE 3 is an enlarged, fragmentary, sectional ele-
[2]3)420,389 3 vational view of the clamping mechanism, and showing in full lines the locking position and in dotted lines the deactuated position of the clamping hook of the clamping mechanism, and also illustrating electrical switch mechanism responsive to actuation of a spring loaded plunger by a locking lug of the clamping mechanism; FIGURE 4 is a top plan diagrammatic illustration of the clampin.- lugs on the rotatable extractor mechanism and showing in full lines the position of such rotatable mechanism when the extractor is disposed in confronting relationship to one side of the storage frame and in phantom lines the position of the extractor mechanism and clamping lugs when it has been rotated 180' to confronting relationship to the other side of the storage frame; FIGURE 5 is a schematic illustration of a hydraul@'@c circuit and associated hydraulic actuated motor units, for powering the clamping mechanism to effect the clamped ,and the unclamped conditions of the extractor when the latter is in predetermined positions with respect to the storage frame sections; FIGURE 6 is a diagrammatic sectional illustration of the directional control valve of the FIG. 5 circuitry; and FIGURE 7 is a schematic illustration of a simplified electrical control circuit for controlling the actuation Of the hydraulic circuit of FIGURE 5. Referrin.- now again to the drawings, the warehousing system herein illustrated may comprise a storage frarre 8 formed of parallel rows of vertical posts 10 definin.- between them an aisle or travel zone 12 in which is adapted to travel a load carrier 14 for depositing a load into or retrievin,g a load from the storage frame. The posts 10 are adapted, in the embodiment illustrated, to support a plurality of vertically spaced load supports 16 which may comprise cantilevered arms extending generally horizontally away from the posts and toward the aisle, for supporting a load thereon. in the embodiment illustrated, the posts 10 are provided with supports 18 mounting rails 20 thereon which rails extend parallel to the aisle above the load supports 16. The aforementioned load carrier 14 may include a mobile bridge 22 extending across the aisle and being supported for movement lengthwise of the aisle as by means of wheels 24 coacting in rolling engagement with rails 20. Bridge 22 may be actuated for mon,ement on rails 20 by any suitable means, such as for instance electric motor 25 suitably coupled to the wheels 24. Mounted on the bridge 22 may be rails 26 extending transversely of the bridge, and which may support a trolley 30 which in turn may support a depending mast 32 extending downwardly into the aisle. Troll6y 30 may be actuated on rails 26 by any suitable means, such as for instance an electric motor 33 suitably coupled to the troliey wheels. Transverse movement of the trolley with respect to the bridge moves the mast with the trolley transversely of aisle 12. The hoist carriage 34 may include a suitable sleevelike member 38 which may have a central vertical opening therethrough receiving the mast and associated preferably replaceable, guiding ribs or bars 40 on opposite sides of the mast. The hoist carriage may support a cab 42 thereon, disposed on one side of the mast, and in which cab an operator may ride. Suitable controls may be located in the cab for actuating and controlling the load handling mechanism as will be hereinafter described in greater detail. On the other side of the mast, the hoist carriage may support a turret bearing member 44 rotatably mounting a turret member 46 (FIG. 4) which supports the extractor means 36, thereby providing for movement of the extractor means either to the right or to the left-hand side of the mast, and thus providing for insertion and/or retraction of loads on both sides of the storage frame. Suitable power means, such as for instance, a reversible electric motor 47 (FIG. 4) mounted on the hoist carriage may be operatively cotipled to for ip5tance, a ring gear 48 4 secured to the extractor means, for rotating the latter about a generally vertical axis. Ary suitable means may be provided for moving the hoist carriage vertically of the mast 32 and as for instance winch mechanism 50 mounted on trolley 30 and suitably coupled to the hoist carriage as at 50a. Extractor means 36 may include a cantilevered support frame 52 comprising a top wall 52a and two spaced parallel tracks 52b which in turn may support the hori10 zontally movable extractor carriage 54. Carriage 54 may have wheels 54a rotatably mounted on the inner sides thereof and disposed in rolling coaction with the tracks 52a on the cantilevered support framework 52 for sul:@porting the extractor carriage for horizontal movement 15 On the tracks. Suitable power means such as a reversible electric motor (not shown) may be provided for driving the extractor carriage 54 horizontally on the tracks 52a and in the embodiment illustrated such motor is adapted to actuate gear means drivingly engaged with racks 55 20 mounted on the bottom of each of the pair of tracks 52a for causing horizontal movement of the extractor carriage. The extractor carriage 54 is adapted to support the load carrying means which in the embodiment illustrated 25 comprises an extractor fork member 56 disposed in cantilever fashion on the extractor carriage. Fork member 56 may comprise an elongated backup beam 56a preferably of hollow construction having load supporting tines 58, 58a extending generally horizontally outwardly there30 from, and with such ti-@ies being preferably movably coupled to the backup beam member for pivoting in a generally horizontal plane. The extractor fork may be of the general type illustrated and described in the copending U.S. patent application of George E. Armington et al., Ser. No. 566,290, filed July 19, 1966 and reference may be had thereto for a detailed description of such an extractor fork construction. Now in accordance with the instant invention, there is provided clamping means 60 (FIGURES 3 and 4) 40 mounted on opposite sides of the hoist carriage structure 34 with such clamping means being adapted for locking coaction with locking members 62 preferably detachably mounted on the rotatable extractor framework 52. Each clamping niechanism 60 may include a supporting bracket 45 structure 63 secured as by means of fasteners 63a to the associated side of the hoist carriage 34 and pivotally mounting as at 64, a reciprocal fluid powered double acting motor unit 66. The cylinder of the motor unit 66 may be pivoted to the bracket 63 while the piston rod 66b 50 of the motor unit may be pivotally connected, as at 68, to a lockii- hook member 70, which in turn is pivoted as at 72 to the@ aforementioned bracket 63. Each hook member 70 may have a tapered locking face 70a (FIG. 3) thereon adapted for wedging coaction with a comple55 mentary tapered face 74 on the respective wedge block or locking member 62. Shims 76 may be utilized in mounting the respective wedge block on the extractor frame 52 and with the face on the wedge block opposite to the face 74 being prefer60 ably provided with a b@-aring plate 78 and including shims 78a, for adjusting the position of the bearing plate 78 laterally with respect to the wedge block proper, and for a purpose to be hereinafter described. Mounted in a housing 79 secured to hoist carriage 34 65 and in generally underlying relation to each clamp mechanism 60 may be a spring loaded plunger 79a, adapted for engagement with bearing plate 78 on the respective wedge block for mechanical actuation of associated conventional spring loaded limit switch LS8. It will be understood that -o when the extractor frame 52 is rotatcd from the position @lhown in FIG. 3, so as to move wedge block 62 from engagement with pltiiger 79a, the plunger is automatically nioved outwardly with respect to its liousing 79 to perniit movement of the spring loaded actuator arm and thus 75 operation of the LS8 switch. Stop 79b may be provided
[3]324205389 5 on the plunger 79a to limit outward movement thereof with respect to housing 79. As can be seen from FIGURE 3, upon retraction of the piston rod of the fluid powered motor unit 66, the locking hook 70 is pivoted upwardly about its pivot 72 and out of coacting relationship with the associated wedge block 62. Upon extension of the piston rod of the motor unit, the locking hook 70 is pivoted downwardly into locking coaction with the associated wedge block. The tapered surfaces 70a and 74 on respectively the locking hook and the locking block 62 provide for a positive urging of the extractor niechanism into aligned relationship with the storage frame section disposed in confrontin.relation to the load handling fork 56 of the extractor mechanism. Referring now to FJLGURES 5 and 6 there is schematically illustrated a hydraulic system @or controlling the actuation of the aforementioned fltiid powered motor tinits 66. Such system may include a reversible pump 80, which may be of the gear type, and which is operated tO furnish the pressurized fluid to the motor units for actuating the same. As can be seen, the motor units 66 are connecte,j in parallel so that actuation thereof occurs simulta-lieously upon operation of the pump. A reversible electric motor 82 may be provided for operating the pump. With the motor 92 running in one direction, the pump 80 may be actuated for instance in the direction of the full line arrow, causing the hydraulic fltiid to flow from the reservoir 84, thereby lifting check valve 86 as the hydraulic fluid passes therethrough. The fluid then flows through line 88 to the suction side of the pump and through the pump, and is forced past check valve 90, with check valve 92 preventing the fluid from returning to the reservoir at this point. The fluid then flows up through line 100 'Lhrou,@h the directional control valve 102, throu.-h pressure switchconnection 104, and into the piston head side of the cylinders of the motor units 66 to actuate the same. As the pressure is built up, the fluid also flows as for instance via line 106 to the passage 108 at the ri,@ht of the control valve 102 (FIG. 6), thereby causina the valve spool 110 (FIG. 6) to move to the left, which positions the spool grooves in line with the ports on the piston rod side of each of the motor units 66. This permits the fluid in the cylinders of the motor units to exhaust, causin@ the piston and associated piston rod 66b to move to the left (with reference to FIG. 5). The fluid exhaustin.- from the motor uiiit cylinders passes back through the tank line 112 to the reservoir. The valve spool will remain in this position until the pump stops. When the motor 82 is shut off, the springs 114 associated with the spool, center the latter closin-, off the exhaust passages and locking the pistons of the motor units 66 in position. With the motor 82 running in the reverse direction, the pump 80 is driven in the opposite direction (the direction of the broken line arrow) and movement of the spool of the directional control valve is reversed, causing the pistons and associated piston rods of the motor units to retract, or in other words move toward the ri.-ht (with reference to FIG. 5). Relief valves 116 may be provided for preventing overloading of the circuitry. The aforementioned pressure switch mechanism 104 in the system may be of conventional type and preferably is a duplex switch, which can be mounted directly to the pump. Each sw;tch therein is a single pole double throw, non-inductive type switch, and a suitablecommercial form of switch has been found to be one manufactured by Oil-Dyne Inc. of Minneapolis, Minn., and known as Model 200 Standard Duty Duplex Pressure Switch. Referring now to FIGURE 7 and assumin- for purposes of discussion that the extractor mechanism is facing toward the left (as shown with reference to FIGURE 2) and the clampin.- mechanism is iii clamping 6 condition, the operation of the load handling mechanism may be as follows. When the control 118 disposed for instance in the cab 42 is actuated by the crane operator preparatory to rotating the extractor mechanism to -5 the right, the contacts 120 controlled by the control 118 are closed. Since the extractor is facing toward the left, switch LS8L is being held open by the engagement of its associated plun.-er 79a with the respective wedge lug 62, thus actuating switch LS8L. However, switch 10 LS8R (on the right side of the hoist carria.-e) is in closed position since its actuating plunger is not being engaged by a wedge lug. Accordingly, "rotation to the ri,@ht" relay coil 1CR is energized, thereby closing normally open relay contacts ICR in line F (FIG. 7) and 15 openiiig normally cliosed relay contacts 1CR i-@l line G. Relay coil UL (line F) is thus energized. Energization of coil UL closes relay contacts UL in theconventional motor circuit of the motor 82 drivingly coupled to the pump 80, causin.- rotation of the pump 20 in a counterclockwise direction (with reference to FIGURE 5) thereby pumping hydraulic fluid in the direction of the broken line arrow (FIG. 5). The pistons and piston rods of the motor units 66 are thus retracted with respect to the motor unit cylinders, causin@ upward piv25 oting of the lockin.- hook 70 of each clamping means 60 about its pivotal axis 72 and unlocking the extractor, to permit rotary motion thereof. The pump 80 conti@iues to operate and builds up pressure on the righthand side of relay coil UL (FIG. 7) and when sufficient 30 pressure is built up (e.g. 1400 p,s.i.) pressure switch PRSWI of switch mecharism 104 is opened while pressure switch PRSW2 is closed. Opening of pressure switch PRSW1 automatically deactivates coil UL, thus opening relay contacts UL in the circuit of motor 82 and stopping 35 the pump 80. When pressure double throw switch PRSWI opens to deactivate the motor 82 of the pump, it completes a circuit to line 122 (FIG. 7) thereby causing energization of relay coil RR, the contacts of which are coupled in 40 conventional manner with the circuit of electric motor 47 for rotating the extractor mechanism, to thus cause the extractor mechanism to be rotated away from the FIG. 2 position toward the right. Since the clamping mechanisms 60 are in deactivated condition as aforedescribed, the 45 extractor mechanism rotates from its confrontin.- relationship with respect to the left-hand storage frame section toward the right-hand storage frame section. The motor 47 continues to rotate the extractor toward the right and the pump 80 for the hydraulic clampina 50 mechanism 60 remains in off condition until limit switch' LSSR is actuated by engagement of the spring loaded plunger 79a on the right side of the hoist carria-e with the confronting abutment plate 78 of one Of th'e locking lugs 62 causing opening of limit switch contact 55 LS8R in line E (FIG. 7) and thus deener.-ization of coil RR to deactivate motor 47 controlling the rotation of the extractor. Openin.- of contact LS8R in line E closes the other contact LS8R' thereof. It will be understood, of course, that as the extractor mechanism was 60 rotated away from its aforedescribed left facin@ position, the locking lu@ 62 on the extractor that was' engaginits associated plunger 79a to hold switch contact LS8L@ (in line D) in open position, moves with the extractor to permit switch contict LS8L in line D to close, thereby 65 permitting switch contact LS8L' in line G to open. Since presstire switch PRSW2 (line G) is in closed condition as aforediscussed, and since switch contact LS8R' is now closed, e-@iergization of relay coii L occurs. Energization of coil L closes relay contacts L in the 70 circuit of motor 82 thus causing rotation of the pump 80 in the opposite direction (i.e. to apply pressurized fluid in the direction of the full line arrow in FIG. 5) to cause outward actuation of the pistons and piston rods of the motor units 66, thereby causing downward piv75 otal movement of the clamping hooks 70 and locking
[4]334201389 7 of the extractor mechanism in positive parallel extendin@ condition with respect to the travel zone and associated storage frame. The pressure continues to build up as the pump continues to operate until stich time as pressure switch PRSW2 opens (e.g. 1400 p.s.i.) thereby stopping the actuation of the motor 82 and lockin.- of the clamping mechanism in clamped condition. If there happens to be any leakage in the system, the pressure switch PRSW2 will reclose to reactivate the pump in the aforesaid direction, to cause reapplication of pressure (e.g. 1400 p.s.i.) to the clamping mechanism at which time the pressure switch PRSW2 will reopen to again cut off the pump motor. It will be seen therefore that the clamping mechanism is automatically actuated upon initiation of acutation of the extractor to rotate it into predetermined condition with respect to the storage frame and with the motor pump 80 being shut off upon reaching a predetermined pressure between the clamping mechanism and the clamping lug as applied by the associated fluid powered motor unitTo return the extractor mechanism to the left (its aforedescribed starting position) the control 118 is actuated to close contacts 124, and since switch contact LS8L is now closed, energization of "rotate to left" relay 2CR will occur to thus energize once more relay coil UL to start the unlocking cycle of th@- clamping mechanism as aforedescribed. Opening of pressure switch PRSW1 will of course energize relay coil RL (instead of coil RR) for rotary energization of the extractor motor 47 back toward the left. From the foregoing discussion and accompanying drawings it will be seen that the invention provides a novel load handling apparatus which includes a load carrier movable alongside storage means in a travel zone and having an extractor mechanism rotatable about a generally vertical axis, together with clampin.- means provided for automatically locking the extrac,lor mechanism in parallel extending relationship with respect to the direction of extension of the travel zone so as to expedite the handlidg of loads by the apparatus. The invention also provides a clamping arrangement which includes means for automatically deactivating the clamping means upon actuation of means for initiating rotation of the extractor mechanism in the opposite direction. We
