DE2340149A1 - AUTOMATED WAREHOUSE - Google Patents

Description

2340H9

81-21.2O7P 8. 8. 1J73

HITACHI, LTD., Tokyo (Japan)

Automated warehouse

The invention relates to an automated warehouse in which the storage and delivery steps are automatic are executed, and in particular to an automated warehouse where the delivery process is such is that the storage capacity and the performance of the delivery process are balanced against each other.

When it comes to warehousing, the most important factors are the storage capacity and the efficiency of the delivery process.

81- (POS 31629) -sch

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The accommodation capacity is related to the accommodation volume of a warehouse, this volume being defined by the standard number of parts or Articles (in the following this standard number is called SNP) of a certain type of goods that can be stored in a pallet are. Accordingly, the maximum accommodation capacity depends on the volume of the storage facility, and the goods must be in the warehouse up to its maximum storage capacity stored in order to utilize the volume of the storage facility as much as possible. So it is necessary to store such a number of articles in each pallet that this number equals the standard number (SWP) for the pallet is.

On the other hand, means the efficiency of the delivery process the ability to deliver goods from the warehouse by operating the conveyor systems installed in the warehouse, for example a stacker crane. During the delivery period it is necessary to use the full capacity of the installed conveyor systems in order to maximize the efficiency of the delivery process obtain.

As already mentioned, it is ideal for warehousing that the goods to be stored utilizing the maximum storage capacity are stored and that the stored goods utilizing the maximum efficiency of the delivery process. Now the accommodation capacity can be used to the maximum, however the performance of the delivery process cannot be maximized in the same way. This is one of the unavoidable disadvantages of conventional warehouses.

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The first is, for example, the number of articles or the number of types of goods that are required by a customer, not necessarily the same as the SNP for a pallet.

Second, the delivery is carried out in such a way that there is, for example, at most one pallet acts, in which goods are stored, the number of which is smaller than the SKP for the pallet (such a pallet is in

oaer -Delaciene

the following as partially loaded / pallet). The number of the goods and the types of goods that are to be delivered to a customer are often different from the number and the type of V / aren stored in the individual partially loaded pallet, so that more than a single conveying process is necessary will.

Third, considerations have already been made about accommodation capacity and to maximize the efficiency of the delivery independently of each other, one has however, no delivery mode has yet been developed that would allow the accommodation capacity and performance of the Delivery are balanced against each other.

It is therefore the object of the invention to provide a control device which eliminates the disadvantage described above and balances the accommodation capacity with the delivery date; the Delivery efficiency can be designed in the maximum way. There should be a suitable number of partially encumbered Pallets are provided in such a way that a reduction in the accommodation capacity is due to a mere increase the number of partially loaded pallets and a reduction the performance of the delivery process as a result the resulting increased operating time of the conveyors is avoided. The appropriate number of partially

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loaded pallets are determined by checking the fluctuations in the quantities of goods delivered during a Period of, for example, a month or a season.

According to the invention, this object is achieved in that Part of the storage capacity is provided for partially loaded pallets, so as to increase the efficiency in an effective manner of the delivery process. That is, the mutual convertibility of the accommodation capacity and the efficiency of the extradition process are taken into account: It is intentionally a Number of partially loaded pallets used, and the partially loaded pallets, the number of which corresponds to the customer's order, are selected at delivery, so that the performance in the operation of a conveyor, for example a stacker crane, can be increased.

In addition, means are provided with a first device to calculate the excess storage capacity from the total number of pallets used, with a second device to determine the number of partially loaded pallets

ssignal
corresponding to the exit / from the first device and with a third device for calculating the relationship between the decrease in the accommodation capacity per type of goods and the increase in the amount of delivered items (delivery amount), the correct number of partially loaded pallets being determined according to the result of the calculations. A device is also provided for determining the coincidence between the number of articles stored in a pallet and the number of articles to be delivered in accordance with a customer order (this is referred to as the "partial number"ordered); Means are provided for calculating the difference between the. the number of parts ordered and the number of articles that are to be

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number of partially loaded pallets are stored, with the the latter number does not match the number of parts ordered by the customer; Furthermore, a device is provided which the number of partially loaded pallets aie allotted the required number of parts, so that the resulting difference, the referred to as "pallet part number" assumes multiple values.

Furthermore, a device is provided for carrying out a pallet allocation process for the number of pallets to be delivered Articles that the number of parts of the pallet is greater than the maximum number of articles that can be stored in a pallet is, multiplied by <x, where iX. a constant which is less than .1, so that the number of parts of the pallet cannot decrease.

Furthermore, a device is provided for selecting a pallet from the number of partially loaded pallets for predetermined ones Types of goods and the minimum number of partially loaded pallets (this number of partially loaded pallets is equal to 1).

The invention thus provides an automated warehouse with a number of shelves arranged one above the other, in which a number of different types of goods are stored, with the articles automatically if necessary be delivered.

The invention is explained in more detail below with reference to the drawing. Show it:

Fig. 1 is a block diagram of an automated warehouse according to the invention

2 shows a structural detail of an automated warehouse;

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Pig. 5 is a block diagram of the number of pallets calculator of Fig. 1;

4 shows a block diagram to explain the compensation of the output signal of the exponential Smoothing circuit with a packing space control factor;

Pig. 5 shows a block diagram of the means for determining the number of partially loaded pallets of Fig. Ij

Pig. 6 shows a block diagram of the device for maximizing the operating performance;

Pig. 7 is a flow chart for explaining the operation and FIG the logical decision of in Pig. 6 shown device;

Fig. 8 is a block diagram showing in detail the device for calculating the value of P, explained;

9 is a flow chart for the logical operation according to FIG Pig. 8th;

Pig. 10 characteristics showing the number of partially loaded pallets and the performance of the delivery process and relate the accommodation space to each other;

Pig. 11 is a block diagram of the Pig. I pallet allocation device shown;

Fig. 12 is a flow chart showing in detail the block diagram and diagram of Fig. 11;

Pig. 14a the fundamental. Factors for Explanation and 14b are essential to a further embodiment of the invention;

15 is a block diagram of a further embodiment the invention.

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Pig. Fig. 1 is a block diagram showing the general structure of an automated warehouse according to the invention. The block diagram shows an automated warehouse 1, a storage file 2 for storing the storage status, ie the actually occupied .Lagerraumes, the automated warehouse 1, a warehouse status calculating device 2 ', uie calculated from the content of the storage file 2, the free storage space per day (this is uie Difference between the total storage space of the warehouse, which is determined by the volume of the storage facility, and the storage space actually occupied at a certain point in time, shown in the form of a volume) as well as the plus per type of goods (the number of goods of a certain type delivered) and the number of Delivery processes (the number of delivery processes carried out per day in accordance with customer orders, an order for the delivery of goods of a certain type being regarded as a unit of the number of delivery processes); a device 3 for introducing partially loaded pallets which determines the correct number of partially loaded pallets which are to be introduced in accordance with the output of the storage condition calculating device 2 '; a pallet allocation device 4 which receives the delivery signal la from a customer 1 Ku, the storage status signal Ib from the storage file 2 and the output signal of the device 5 for introducing partially loaded pallets and which selects pallets in accordance with the delivery signal la; and a crane control device 5 _f which controls a conveying device, for example a stacking crane, by receiving the output signal of the pallet allocation device 4. In this way, the customer receives the goods Ic delivered.

Pig. 2 shows a concrete arrangement of the automated warehouse 1. The storage racks on top of each other in the pallets 40 stored articles are lifted by a stacking crane

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41 promoted out. The corresponding pallet is placed on a Brought delivery platform 42, via a sorting platform representing belt conveyor 42 'of a storage platform 42' and brought back again by the stacking crane 41 into the storage shelves 40. The one in Pig. I shown facilities are described in detail below.

Pig. 3 is a block diagram of the storage condition calculator 2 ', which calculates the average value over a period of about one month on the basis of the output signal of the memory file 2; The device 2 'is essentially formed by a number of exponential smoothing stages. The output of the memory file 2 is converted by an input detector 44 into a desired signal, e.g. B. a signal representing the plus of items of each type or the number of deliveries, and so an input signal 45 for the exponential smoothing circuit can be obtained. A multiplier 46 forms the product of the input signal 45 and a signal ε, which is supplied by an evaluation parameter setting stage 47 (where O < 6 <1.0, and C is a reciprocal of the time constant in the G-smoothing operation), and the product is fed to an adder 50. The output signal of the evaluation parameter setting stage 47 is fed to a complement computer 48, in which a complement of 1.0, ie (1 - <£) »is obtained and fed to a multiplier 46 '. The multiplier 46 'forms a product of the complement (l - £) and the output signal 55 ^{f of} a mean value storage stage 53 which stores the mean values obtained above (e.g. the mean plus of goods of every kind, the mean number of delivery processes of articles of every kindj / and the output signal of the multiplier 46 'is fed to the adder 50. The output signal of the adder 50 is fed to a gate stage 52 which is

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signal from a clock signal generator 51 opened and closed will renew the above mean, as a result the newly calculated mean value is stored in the mean value storage stage 53. Signals 54 are therefore grounded got, ow the middle flow of were every kind xmd that average number of delivery processes over a period of time from ei; wa one month corresponds to: !!,

Pig, FIG. 4 shows a further example in which the output signal of the memory file 2 is converted by a signal converter J1 into a signal which represents the unoccupied storage room on the day in question; the signal is smoothed by an exponential G smoothing stage 2 ¹ , a supplementary signal 70, which compensates for seasonal fluctuations, is ^{added to the output of the exponential smoothing stage 2 ft} via an adder 7, and a multiplier stage 8 forms the product of the output signal of the adder 7 and a signal 80 which represents the occupancy factor controlling the partial number, so that a signal 54 'is obtained which corresponds to the storage room for the partial number control. The occupancy factor controlling the partial number takes into account the fact that the storage space is partially occupied by stacking space due to previously performed stacking steps in order to shorten the time between an order being received and the delivery to a customer. The signal 80 may be referred to as the stacking space control factor and, along with the storage space and the efficiency of the warehouse operation, biles
det / one of the most important factors for proper control of warehouse operations.

The device 3 for introducing partially loaded pallets will now be described. Fig. 5 is a block diagram of this device 3. A level 9, which as a storage room for the partial number control, the sum of the number (IV) -! partially loaded pallets

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sets for individual types of goods, receives at its input the signal 54 ', which the storage room for the partial number control is equivalent to. A stage 10 for calculating each number (P,)., Thereby achieving maximum operating efficiency performs an arithmetic operation (1), the condition that / 3 is the sum of the numbers (Pj.). is limited. The operating efficiency Aq is as follows:

^A o = £ ^ k ^S1TJ? * ^H t> ⁿ i -

P (P, .SICP.W,) = the speed with which the number of operations of the stacker crane decreases, as a function of P _k , SNP and N _t ;

P, = the number of partially loaded pallets for each

Type of goods;

SNP = the standard number of parts or articles that are stored in each palette;

N ₊ = the number of delivery processes of a series recorded in the list (the sum of the types of goods ordered by customers for one day, for example);

n-j- = the ratio calculated for each type of goods, where it is the ratio of the number of transport processes of partially loaded pallets for one day corresponds to the number of delivery operations of the stacker crane for one day;

Cb = a coefficient that represents the rate at which the mean cycle time increases when an additional partially loaded pallet is picked up.

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The above calculation is only used to obtain a number (-P ₁ ).

ic χ

carried out in order to maximize _{the performance A Q.}

Prop. Figure 6 is a block diagram of circuit 10 for maximum operating efficiency. A comparator 14 compares the output signal 9 'of the stage 9, the number (P-,). partially loaded pallets for individual types of goods totaled, and the output signal 13 'of the computing stage 13 for the sum of (P _v ), · »and if these signals 9 ^! and 13 '. are coincident, the output signal of the "comparator 14- is stored in a P -.- memory stage 15, if the comparator 14 determines that the signals 9' and 13 ^{! are} not coincident, λ. is corrected by a correction stage 11 which corrects the preset value of. ". As a result, a stage 12 begins which calculates the value of P-, der (Fn _T - CB-. - iVP _v ). for the corrected fourth of \ to operate upon receipt of the signal 54 corresponding to the above-mentioned average flow or number of deliveries. According to this operation, the constraint conditions are entered into the numerical value determination function based on the Lagrangian method of the indefinite coefficient, and the maximum of the sum of plural terms is obtained by calculating the maximum value of each term. If, according to the Lagran method, it is assumed that (new numerical value determination function) = (original numerical value determination function) + "λ and the restriction condition is also met.

Figure 7 is a flow chart showing the operation and logic Level 10 decision to maximize operational efficiency, the block diagram of which is shown in FIG

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is explained. A block 7a denotes an operation at which has an old or original value of A set. In a setting stage 7b, the type of goods i = 1 is made, while in an operation stage 12 the same operation as in stage 12 of I'ig, 6 is performed. A decision-making level 7c checks whether all operations for all types of goods have been carried out in full, and if these operations are not yet fully executed, a renewal operation performing stage 7d renews the kinds of goods by substituting i = (i + 1) so as to complete the above operations.

When all operations for all types of goods have been carried out in full, a comparator and decision-maker stage 7e compares the sum of the values of (P ₁ ). with the associated restriction value, and if these coincide, the sum is stored in a P -, storage stage 15. However, if the sum is greater than the constraint value, renews a ^. - Renewal stage 7h the value of A by inserting & λ.- + £ (with £ any small number such as £> 0) j but if the sum is less than the restriction value, the iJtux'e 7h renews the value of Λ- Insertion of Ix Tl = z - d. In this way operations continue for new values of Λ-.

Pig. Fig. 8 is a block diagram explaining in detail the calculation stage 12 for calculating the P - ^ values. The block diagram shows a calculation stage 16 for calculating the value of p (P _k . SHP * 3tf _t ) nj- for P _k values, which are obtained by a stage 30 for setting and correcting the values of P ^. to be delivered; The circuit also has a stage 17 for calculating the speed pP _k at which the cycle time increases (this is a period of time during which the stacking crane 41 of FIG.

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command signal 3 takes out the palette from the selection platform 42 "is selected, fed to the storage platform 42 'and returned to the old position on the shelves 40 will); a stage 18 is provided for calculating the storage space consumption ^ Pjj-J a stage 19 calculates the Sum of the calculated results from calculation levels 16, 17 and 18; and a stage 20 determines whether the output of the stage 19 has a maximum value or not. If it is determined that this output has a value deviating from the maximum value Value, the P -.- value is corrected by step 30, and the operations already described are repeated. if on the other hand this output has its maximum value, the assigned P ^ value is temporarily stored in a storage stage 21 saved * Levels 11 and 13 have already been described. ■. ■ '. ■■

The flow of the operations described above is described with reference to Pig. 9 described. The initial value setting step 9a performs a setting operation so that Ρ · ^. = 1.0 and A '= 0. A level 9b for calculating an estimated value consists of a combination of levels 16, 17, 18 and 19 according to Pig, 8 and calculates the estimated value A, A rating level 20 (which corresponds to level 20 of Pig. 8) determines whether A is the maximum value or not. If (A - A ¹ ) <0, then the maximum value is determined and the value of A is stored in a memory stage 21. However, if (A - A ¹ )> 0, then the values for P ^ and A at this point in time are replaced by ΡΛ or A ^f with the help of a substitution stage 9c. An evaluation stage 9d determines whether the value of P ^ is greater or smaller than a constant value C- ,, and if P,> C- ,, a substitution stage 9e replaces P, with C ₁ , so that P, = C- , is made, and the substituted value O ₁ v / is stored in a memory stage. If an-

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on the other hand P <G- ,, generates an adjustment and correction stage 30 for P, a new value P, which is related to the old P. value is corrected and is equal to your old value P ^ + 1, d. H. so P-. = (P, + 1), and the other operations become continued.

The constant value C- already mentioned is now calculated using the characteristic curves of Pig. IO explained, the abscissa denotes the number P ^ partially loaded pallets, and the ordinate denotes the efficiency of the delivery process and the storage area. The curve 10-a denotes the improvement in the performance of the delivery process due to the decrease in the number of delivery processes; curve 10-b denotes the decrease in the performance of the delivery process due to the increase in P ^. and the cycle time; curve 10-c denotes the improvement in the performance of the delivery process due to the synthesis of curves 10-a and 10-b; and curve 10-d denotes the reduction in memory space due to Pv-, the constant C-, i3t a value of P ^. at which curve 10-a flattens out, and G ₁ can therefore be referred to as the critical point over In addition, the performance of the delivery process is saturated with the increase in the number of partially loaded pallets.

The pallet allocation device 4 shown in FIG. 1 is now described in detail. This facility is used to determine the coincidence between the line number accordingly the order of a customer and the number of partially loaded pallets within a range of a permissible Number of partially loaded pallets. A stage 22 for storing the partial number corresponding to the customer's order for goods stores the delivery signal la received from the customer. A level 23 for storing the number of partially loaded pallet

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ten existing in the automated warehouse stores the contents of the in l ^? ig. 1 storage register 2. A first stage 24 for the determination of the number of partially loaded "pallets, the coincidence between the number of certain partially loaded pallets and the partial number according to the customer order in response to the output signals of the memory stage m. 22 and 23, so that a signal 24a is obtained from a stage 28, which stores the allocation of divided-loaded pallets. If, as a result of the determination by the stage 24, there is no underloaded pallet, the partial number of which is identical to the partial number corresponding to the customer order, a second stage sets 25 to determine the number underloaded pallets continues a detection process, following the operation of the first stage 24, the second stage 25 determines a certain partially loaded pallet which is coincident with the sum of two partial numbers according to the conditions of two customers, so that a signal 25a is received from the stage 28. If, as a result of the Fe If the detector stage 25 does not detect a partially loaded pallet which fulfills the detection condition, the detection operation is carried out by a detector stage 26 for partially loaded pallets which have a low storage restriction on v / iron. The stage 26 is an allocation detector stage which carries out the delivery allocation according to the customer order in such a way that the remaining partial number can be below a certain restriction value Y ¹ , which will be described later. The value Y 'applies to the remaining partial number after the delivery allocation and is related to the coefficient N ₂ which restricts the partial number in the following way:

Y »= N ₂ . SNP (2)

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Usually M ^ is chosen with 0.4, i.e. h, i.e. Mp = 0.4, so that the locking operation is in accordance with the following expression is carried out:

(remaining partial number)> 0.4 SNP (3)

A signal 26a representing the resulting allocation is then applied to a stage 28 for storing the allocation of partially loaded ones Pallets stored, üline detector level 27 is used to perform the allocation operation so that the remaining partial number does not go to a particular pallet is concentrated, but can be distributed over a number of partially loaded pallets, with the remaining partial number is above a predetermined constant. The resulting output signal 27a is stored in the memory stage 28 ,

A level 29 to change the order of delivery dasu serves to rearrange the data of the delivery allocation stored in the storage stage 28 according to the order of customer orders, and the output signal 29a of Stage 28 controls the stacker crane when executing the actual delivery process.

The Pig. 12 and 13 are flow charts detailing the series of plague operations according to Pig's block diagram. Describe Il.

In Pig. 12, an operation stage 12a can be seen for compiling a list of partial numbers corresponding to customer delivery orders; this stage performs a processing operation which is equivalent to the operation of the memory stage 22 shown in FIG. 11, while an operation

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stage 12t) carries out a processing operation equivalent to that of the storage stage 23 of Pig, 11 to compile a list of the partially loaded pallets in the warehouse or 25 from Pig. Il is similar. A discriminating stage 12d determines whether or not a new combination exists, and if the existence of such a combination is not found, a detecting stage 12e, as a next operation, carries out a processing operation equivalent to that of the detecting stage 26 or 27 of Pig. T \, A Entsheiderstufe 12f determines whether a new combination exists or not, and if the existence of such combination is not determined, a detector stage then performs 13a (see FIG. Pig. 13), a processing operation. Then, the evaluating operation is repeated by an allocating stage 13b until a new combination is no longer detected, so that an allocation operation is carried out by an allocating stage 13c in accordance with the resultant evaluation. Finally, a processing stage 13d for rearranging the delivery allocation data according to the delivery order performs a reordering operation.

The description of the invention has so far been made through the description of a particular embodiment, however, the invention can also be practiced by a system in which the operations for the control parameters can be simplified. Such a system is described with reference to Pig. 14 and 15 described.

Pig. 14a shows, dashed, characteristic curves that show the value of SNP, the mean plus and the correct number of N. partially exposed

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-ib-

Relate pallets to one another. Assuming that for the Pail that

SNP> SNPc and, _N _ the middle plus> APc '' *

and that in case

SNP S SHPc and 7 _w

the mean flux * = APc S ^{τ το}

then the simplification shown in FIG. 14b is possible.

Pig. Fig. 15 is a block diagram of one with reference to Pig. 14 described system. In Pig. 15 will be for Pig. I. The same reference numerals and symbols are used for corresponding parts, and the details of equivalent parts are given not described. A stage 58 for determining the number of partially loaded pallets determines this number on the basis the output signal of a storage room computing stage 2 ', the output signals a stage 55 for setting a reference value SNP, d. H. SNPc, to control a number of partially loaded Pallets, a stage 56 for setting an average reference flow APc for controlling a number of partially loaded Pallets, and a step 57 for setting a reference value for the correct number of partially loaded pallets.

With this system, the correct number of partially loaded pallets is determined beforehand with N. or 1, and each of the values N. and 1 can be selected. According to this system, the

XC '

Control device can be simplified.

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Claims (1)

2340H9 P a t c η t a η s ρ r ti- c h e (l / Automatisiex * tes warehouse with a number of pallets and a device for.! '' order these pallets in a certain position, characterized by a device (2) door for storing the storage status of the pallets, a device (2 ¹ ) for setting the number of delivery orders and means (4) for performing an allocation operation on the basis of the stock status and the number of delivery orders, the warehouse containing a number of partially loaded pallets for goods of one type. 2. Automated warehouse according to claim 1, characterized by a device (2 ¹ ) for calculating the excess storage space on the basis of the signal which is stored in the storage device containing the storage condition (2), wherein the output signal of the computing ^{device (2 1} ) of .einer Means (5) is obtained which determines the number of partially loaded pallets so that this number is controlled. 0. Automated warehouse according to claim 1, characterized by a device (5) for determining the number of partially loaded pallets to be used, with a device for calculating a ratio value per type of goods, namely the reduction in storage space for each type of goods as a result of the increase in the number of partially loaded pallets Pallets for corresponding types of goods · δλχ the increase in the number of articles to be conveyed out, whereby the number of partially loaded pallets is calculated and controlled in such a way that the output signals of the device for the respective types of goods can be identical to one another. 409803/0 9 26 BATH ORIGINAL ' 4. Automated warehouse according to claim I _1, characterized by a device (4) for performing a pallet allocation operation, with a device for plaguing the correspondence between the number of articles stored in the respective partially loaded pallets and the number of articles corresponding to the delivery orders, the corresponding partially loaded pallets are determined as pallets to be conveyed out, 5. Automated warehouse according to claim 4, characterized by a device (4) for carrying out a pallet allocation operation, with a device for calculating the difference between the number of pallets in the partially loaded pallets stored articles and the requested number of articles if there is no match and with a Means for determining a correspondence between the number of stored articles and the number of requested articles in.der way that the output signal of the computing device has a number of values which are greater than a predetermined Are constants, can assume. 6. Automated warehouse according to claim 1, characterized by means for determining the correspondence between the number of articles stored in the respective partially loaded pallets and the number of delivery orders corresponding articles, a device for calculating "the difference between the number of items stored in each of the partially loaded pallets, the number of which does not match the number of items. assigned Number of articles according to the delivery orders, and the assigned number of articles according to corresponding delivery orders, and a device for determining the correspondence between the number of stored in a partially loaded pallet 409808/0926 cited article that is smaller than the maximum in the Pallet storable number of articles and the assigned number of articles according to the delivery order, if no match is found. 7 »Automated warehouse for storing articles of various types according to claim 1, characterized by a device (55) for prior setting of the sum SNPc of the number of articles in partially loaded pallets and by means (56) for prior setting of the average flow APc for each type of article and by means which replace the preset number of partially loaded pallets with N ^ ₀ if the sum or the mean ITuss exceeds a predetermined setting value. 409808/0926 Blank page