Patent Publication Number: US-3880307-A

Title: Bin address memory system

Description:
United States Patent Peterson 1 Apr. 29, 1975 BIN ADDRESS MEMORY SYSTEM [75] Inventor: Robert H. Peterson, Salt Lake City. ABSTRACT Utah A computer-controlled warehousing stacker bin ad- [73] Assignee: Kenway Engineering, Incorporated, dress memory System using Clock Signals! and compris&#39; W d Cross U h ing a keyboard or the like for introducing binary bin address data into the system and for issuing command [22] Filed: 1973 signals and enable signals to a control circuit compris- [21] A N 336,234 ing a priority encoder and a preset read only memory.  
  One set of shift registers, with digital display, is enabled to receive input address data. Thereafter, com- U-S. t A mand and enable functions Cause data from the [51] Int. Cl Glle 7/00; B65g 1/00 play registers to be issued through a Set of execute [58] held of Search 340/1725; 214/1 shift registers to a data transmitter which controls op- 214/11 17 R eration of the stacker crane and, where preservation of an address is needed, as when the tote pan is being [56] References cued delivered to the picking station, to place said data in a UNITED STATES PATENTS predetermined one of a plurality of sets of storage 3.576.978 5/1971 Rosenberg 340/1725 Shift registers, from which the data is likewise, thereaf- 3599156 8/1971 Miller l/l ter. transmitted to the E registers to cause the stacker Primary Eraminer-Garfith D Shaw Assistant Examiner-Paul R. Woods Attorney. Agent, or FirmLynn G. Foster crane to return the tote pan to storage upon command.  
 3 Claims, 1 Drawing Figure SERIAL BINARY CODED DECIMAL BIN ADDRESS DATA FROM CARD READER OR KEYBOARD SDI $02 l6 0 I Z 3 A B26 0 DUAL4-TOI LINE MULTIP PQIORITY ENCODER ONLY MEMOEY PARALLEL I Z 3 LEXERS lGOIZSABZGOIZS DUAL 4TOI LINE MULTlPLEXERS LEFT,L REGlsTERS RIGHT, R REGISTERS DISPLAY, o REGISTERS pARkLLEL BCD DATA TO 7 SEGMENT LED DISPLAY sxacurt, E REGISTERS 5CD DATA TO THE STACKER CRANE SERIAL DATA 1&#39; RANSMITTER BIN ADDRESS MEMORY SYSTEM BACKGROUND 1. Field of Invention The present invention relates generally to computercontrolled warehousing systems using stacker cranes and more particularly to a novel bin address memory system for such warehousing systems permitting retrieval of a tote pan from a right or left bin storage location, placement of the tote pan center, right or left at a picking station and restoration of the tote pan to the desired bin location. The subject matter of US. Pat. Application Ser. No. 336,109, filed Feb. 26, 1973, also assigned to the present assignee, is incorporated herein by reference. Said application is now US. Pat. No. 3,809,259 granted May 7, 1974.  
 2. Prior Art Warehousing systems comprising stacker cranes are used to automatically pick up and deliver tote pans or pallets from bin storage on either side of a warehouse aisle. The address of a desired tote pan storage bin is sent to the stacker from a keyboard or card reader at a picking station, following which the desired tote pan is brought from bin storage and is deposited at the picking station. Here order-picking personnel remove the required parts, transistors, resistors, nuts, bolts, washers and the like from the pan. The parts are counted or weighed, labeled and packaged for delivery to the customer. When the operator has completed his task, he uses the keyboard to command the stacker to return the tote pan from the picking station to its proper bin location.  
  Previously proposed warehousing systems of the type under consideration have been limited in the following areas:  
  I. Tote pans retrieved from bins on the right side of the aisle have heretofore been capable of being delivered only to a right side location at the picking station, and vice versa. This severely restricts the number of order-picking personnel who may function efficiently at the picking station.  
  2. The bin address of the tote pan retrieved and placed at the picking station must be re-entered by the operator prior to restoration. This permits human error.  
  3. Only two bins can be accommodated at the picking station at any one point in time, one on the left and one on the right.  
  4. There is either no bin address memory system or an inadequate memory system in relevant prior art warehousing systems.  
  5. In some such systems, photoelectric reflective tape readers are used to. read the bin address from the tote pan as the bin is in the process of being restored in order to prevent loss of the bin address.  
 BRIEF SUMMARY AND OBJECTS OF THE PRESENT INVENTION The present invention comprises a novel bin address memory system for computer-controlled stacker cranes wherein a tote pan from a storage bin on the right or left side of a warehouse aisle may be automatically delivered to the center, left or right location at a picking station. Time is saved and the human error alleviated in addition to which a higher number of order-picking personnel may function efficiently at the picking station at the same point in time. The address of each tote pan at the picking station is electronically preserved, eliminating the need to re-enter the address or to externally read the same and re-introduce the reading into the stacker electronics. Restoration of a tote pan to storage, therefore, requires only that the operator depress a restore button.  
  It is a paramount object of the present invention to provide a novel computer-controlled warehousing stacker bin address memory system.  
  It is another significant object of the present invention to provide an improved stacker bin address memory system which preserves each retrieved tote pan bin address while accomplishing tote pan retrieval from its storage bin on either side of a stacker aisle and placement of the retrieved tote pan at either side of a picking station or in a central disposition at the picking station.  
  It is another primary object to provide a novel stacker crane bin address memory system which accommodates memory preservation of the bin address of a retrieved tote pan and accomplishes restoration of the tote pan from a left, center or right position at a picking station to the correct bin location defined by the address.  
  These and other objects and features of the present invention will be apparent from the following detailed description, taken with reference to the accompanying drawing.  
 BRIEF DESCRIPTION OF THE DRAWING The FIG. is a circuit diagram of the presently preferred computer-controlled warehousing stacker bin address memory system of the present invention.  
 DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENT The preferred bin address, using the present system, is a four to six digit number, depending on the size of the warehouse. In situations where a four digit number is used, the thousands and hundreds decimal digits are used to identify the horizontal bin location. Thus, if the thousands and hundreds decimal digit is the stacker crane would be commanded toproceed down the warehouse aisle until it had reached the 35th vertical column of bins on either side of the aisle. The tens and units digits are used to define the vertical bin location. If the units digit is odd, the bin location will be on the left side of the aisle, if even on the right. This number instructs the stacker crane not only as to the side from which retrieval is to be made but the correct vertical elevation of the bin containing the tote pan to be retrieved.  
  S R R D EE EEE E E 0608 &amp;o&amp;&amp; T F EDDERLD Elm a IGT K firs +3113 SRDT CDRLDDDD 7 O H 505 555mm PE 3 00110000 Tammi; mmaw mm M 5m No 01101 1 h u mwm PmHmm TQJEWHQ W Mmd m6 10110001 3 mmmfinm xnrqm MEDUMXM W mom :6 01111111 mam/ 2m xUOQQ Emmi R mug m0 0 0010010 mqmmtrm .Ffimm Emmi mwq m0 000010 m tmfmm mooqo BZUHm m mom MG 00100100 m hmmzm BmHIm BEUHm P mmm 00000100 0 4 0 l 0 l 0 l O 1 WE 211001100 3 DU .1OP w 11000011 ECT NU m 00111111 EO 252:8 HZ. wwwwm m z m BBRLCBBB ESRRRDDD 2.55 mmaoozm G wwofiqofiwwsw terminals of priority encoder El. Priority encoder E1 is preferably integrated circuit SN74147 manufactured by Texas Instruments (see page 147 of said Texas Instruments text) and serves to convert nine bits of data mally, when the keyboard is inactive, all of the input signals to priority encoder E1 will be high, a state where nothing is occurring. When it is desired to enable the primary encoder E1, the voltage signal EB No.* is  
 tinue high. It is to be appreciated that the priority encoder El functions such that, with respect to the site designations 1-9 on the interior of E1, the low signal, if only one occurs, or the rightmost low signal, if more 55 than one low signal is presented, constitutes the El input and the collective output at sites A-D at pins 9, 7, 6 and 14 will be the complement of said El input. Consequently, in the state just mentioned when signal EB No.* goes low, the input to priority encoder E1 is It is further to be appreciated that when any input signal to El goes low following receipt of the EB No.* siging the low voltage signal to control the output of priority encoder E1. The letter designation of the input signals to E1 are defined as follows:  
 O\ l. \0 Ln: m N H E l ROM PIN #E l INPUTS TABLE 1 REGISTER CONTROL PRIORITY ENCODER AND READ ONLY MEMORY TRUTH TABLES The bin address may be manually entered into system by a ten-key keyboard or automatically from a card reader or computer. The binary address comprises binary ones and zeros appearing at inputs SDI, SD2, SD4 and In a manner hereinafter 0 be xpl in the into four lines containing the same information. Norindicated input bin address is passed by dual 4 to 1 line multiplexers E2 and E3, upon receipt of clock pulses to a set of display (D) registers El6-El9. Preferably, multiplexers E2 and E3 each comprises integrated circuit SN74153, manufactured by Texas Instruments and disca d t go l Th other i l as ide tifi d closed on page 302 of the text The TTL Data Book for Design Engineers, copyrighted 1973 by Texas Instruments, lnc. The D registers E16-El9 communicate the binary bin address to a seven segment light emitting diode display, in a well known manner.  
  The keyboard is equipped such that if the wrong address is entered in the display registers, it may be cleared by pressing the proper keyboard button causing the display register reset signal DRR* to go low, clearlhg p y registers following which the a 9 and the output is the complement of binary 9, i.e. rect entry may be made by the operator.  
  It should be understood that signal 88* is used to send a new bin to warehouse storage for the first time. Specifically, the address in the D register is caused to be shifted to the E register. This function is also used nal, the EB No.* signal returns to its high state, allowto restore bins after a power failure.  
  The card reader or keyboard causes the input signals identified on the drawing to selectively reach the input DBC* Deliver Bin Center DBL* Deliver Bin Left DBR* Deliver Bin Right RCB* Restore Center Bin RLB* Restore Left Bin RRB* Restore Right Bin 58* Store Bin EB No.* Enter Bin Number.  
  Reverting to the condition when signal EB No.* is low and remaining inputs to priority encoder El are high, a binary 6, the complement of 9, is passed to the read only memory (ROM) E4. Preferably, read only memory E4 is integrated circuit lM5610 manufactured by lntersil, Inc. of 10900 North Tantau Ave., Cupertino, Calif. 95014. See all six pages of the Technical Bulletin entitled lntersil 256 BITOLAR READ ONLY MEMORY lM 5,600 IM 5,610. The ROM E4 is preset (electrically programmed) in its condition to create as an output any of the ones centrally listed in Truth Table 1, when the adjacent corresponding input to E4 exists, as shown on the left thereof in Table 1. Consequently, when EB No.* is low, the Q3 output is high and the remaining outputs of E4 are low. The O3 high signal is designated DSE (display shift enable) because it conditions display (D) registers El6-El9 to receive the bin address earlier keyed to the dual 4 to 1 line multiplexers E2 and the E3. The low state of E4 terminals Q1 and O2 (signals RTA and RTB), which connect to terminals A and B, respectively, of E2 and E3 together form a zero state causing the inputs at the two zero terminals to be gated to output terminals lY and 2Y. This circuit is of such a nature that when the input signals RTA and RTB at terminals A and B are both binary zeros, the lY and 2Y outputs are connected to the input terminals; when RTA and RTB are a binary one and zero, respectively, the gates within integrated circuit E2 and E3 connect the lY and ZY outputs to the 1 input terminal; when signals RTA and RTB are zero and one, respectively, outputs lY and 2Y are connected to the 2 input terminals; and when the RTA and RTB signals are both binary ones, the 3 input terminals are gated to the lY and 2Y output terminals. By reason of the feedback connections between the multiplexers E2 and E3 in respect to the various sets of shift registers, proper address retention and retrieval is accomplished as more fully described hereinafter. Since only the flip-flop display shift registers El6-El9 are enabled to receive the binary bin address, the address is registered only at El6-El9. It is to be appreciated that all of the registers shown in the drawing from E8 through E23 are preferably integrated circuit SN74164 manufactured by Texas Instruments (see page 334 of said Texas Instruments text), each of which comprise 8 shift register flip-flops having eight true outputs only. In the circuit arrangement shown in the drawing, only the four of the eight true outputs are used, although the invention is capable of other configurations.  
  At this point in time, a high state exists at terminals 1 and 2 of each display register E16-E19. A clock signal 4SC is input to terminal 8 of each display register El6-El9 causing the binary bin address to enter at lo- 60 cation one and shift from left to right to the fourth location. This binary number once placed in the display register is visually displayed on a 7 segment LED display.  
 . 65 It is to be appreciated, in the illustrated embodiment,  
 that all registers shift data from left to right only. It is also to be appreciated that clock signals 4DC and 45C are preferably pulses derived from a suitable clock issuing 4 pulses per operation. Moreover, in respect to each illustrated register, the left column will receive and store only a binary l, the second column from the left a binary 2, the third a binary 4 and the fourth a binary 8.  
  From the foregoing and Table 1, the manner in which the priority encoder E1, the read only memory E4, the multiplexers E2 and E3 and the registers in sets E8- Ell, E12-El5, El6-E19 and E20-E23 function for each input at priority encoder E1 should be apparent. Selecting, for purposes of example only, a situation where the keyboard operator depresses the deliver right bin&#34; key causing the DBR* signal to go low, the priority encoder E1 would output the complement of 4, i.e., a binary 11. Read only memory E4 would then have high outputs at sites Q2, Q4, Q7 and Q8, the other outputs being low. The O1 and Q2 outputs (RTA and RTB, respectively) being low and high, respectively, condition multiplexers E2 and E3 such that the 1 input terminals are respectively gated to lY and 2Y output terminals. The high signal from O4 (ECE) enables AND gate E7, while the high voltage signal from O7 (RCE) enables AND gate E6. The high signal from O4 (ECE) is also delivered to each of the execute (E) registers E20-E23 at the 2 input terminal thereby enabling those registers. The positive voltage signal (RSE) from terminal O8 is delivered to the 2 terminal of each of the right (R) registers E12-E15 to enable the same. Because of the described state of multiplexers E2 and E3, the data stored previously in the D registers El6-El9 is communicated from the 6 output of each register to the 1&#39; input of multiplexers E2 and E3 and from thence to enabled R registers El2-El5. At essentially the same time, four clock pulses (4SC) are issued, being received at AND gates E5, E6 and E7. Since the LCE input to AND gate E5 is low, the high clock pulses do not change the state of E5 and its output remains low. To the contrary, both inputs to AND gates E6 and E7 are now high and the output will be high. Thus, AND gates E6 and E7 pass the four clock pulses to the 8 input of R registers E12-E15 causing the bin address previously in the D registers El6-El9 to be placed in the left position and sequentially shifted to the right position in the register. At the same time, the identified bin address previously stored in the D registers E16- E19 is also placed in the left location and shifted to the right location in E registers E20-E23 and parallel output by a data transmitter to the stacker crane. Thus, the tote pan, the address of which is transmitted, is caused to be retrieved by the stacker crane, brought to the picking station and shifted to the right at that station 55 for removal of desired merchandise.  
  In like manner, as can be appreciated from a careful examination of Truth Table l, the addresses of pans being delivered left and right, respectively, to the picking station are preserved in L registers and R registers, respectively, and each of said stored addresses is passed to the D and E registers when the corresponding pan is to be returned to its storage bin location. The notation in the right column of Table l, C+K, means the input signal from the card reader or keyboard, depending upon which is being used.  
  It is preferred that the EB No.* signal be retained high when a tote pan is delivered by the stacker crane to the center position of the picking station following delivery of the DB signal to the priority encoder El. This disables the priority encoder, making it impossible for the operator to effectively signal for delivery of an additional tote pan. Otherwise, a plurality of tote pans may be delivered and situated in left, right and, lastly, center positions, the electrical system illustrated in the drawing accommodating storage and retrieval of the address of the left tote pan in the L registers, the address of the right tote pan in the R registers and the address of the center tote pan in the D and E registers.  
  The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.  
  What is claimed and desired to be secured by United States Letters Patent is:  
  l. A method of controlling an automated warehousing system comprising a stacker crane, storage bins and tote pans, the steps of:  
 issuing binary bin address signals identifying the storage bin location of a tote pan desired to be retrieved on either side of a stacker crane traversing aisle;  
 communicating said binary address signals to gating means;  
 issuing enable signals to the gating means;  
 gating said bin address signals to a first memory;  
 issuing tote pan retrieve command signals from control means to said first memory causing the bin address data to be fed back and gated through said gating means to both a storage memory and through an additional third memory to a data transmitter which controls the stacker crane to retrieve the desired tote pan and locate the same at a picking station.  
  2. A method of controlling an automated warehouse system comprising a stacker crane, storage bins, tote pans and a plurality of memory means, comprising the steps of:  
  providing command signals and sets of binary address data;  
 priority encoding said command signals;  
 gating said sets of binary bin address data sequentially to an initial memory location;  
 selectively processing said priority encoded signals to initiate ultimate successive retrieval of up to three tote pans from storage bins respectively corre sponding in-location to said successive sets of binary bin address data;  
 serially gating said successive sets of binary bin address data from said initial memory location to both (a) another memory location and (b) an output location by which retrieval movement of the stacker crane is controlled;  
 communicating processed priority encoded command signals to said output location commanding retrieval of said tote pans at said bin address locations respectively to a picking location;  
 returning retrieved tote pans from said picking location to their respective bin address locations by separately gating said sets of binary bin address data from said other memory location to said output location and from thence to the stacker crane by which restorative movement of said stacker crane to return said tote pans to said storage bins is controlled.  
  3. The method of claim 2 comprising deriving enabling signals from said priority encoded signals to control said gating steps.