JP2830204B2 - Work sorting device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a work rearranging apparatus in a production line for various kinds of works, such as automobiles, and more particularly to an apparatus capable of coping with a very large number of kinds of works.

[Related Art] In a production line of an automobile or the like, it is often necessary to produce various products by vehicle type and specification. On the other hand, this production line has not only an assembly line but also a plurality of processing lines such as a painting line, and each line has various restrictions.

For example, in a painting line, there is a demand to continuously paint vehicles (work) of the same color, while in an assembly line, there is a demand that three or more cooler-equipped vehicles are inserted at intervals. In addition, there is also a demand on the assembly line that it is necessary to equalize the production volume of products of each model and specification so that the production volume conforms to the monthly production plan.

Therefore, to satisfy these different requirements,
It is necessary to rearrange the works at the connection part of each line.

Therefore, conventionally, a work rearranging device is arranged at a connection part of a different production line, and the work is rearranged so as to meet a requirement for a work input order in a next line.

Fig. 6 shows the work carried in to the assembly line (vehicle 100)
1 shows a general configuration of a work rearranging apparatus that performs rearrangement. For example, the vehicle 100 that has been carried in by the carry-in conveyor 110 from the painting line that is the front line,
It is supplied to the carry-in traverser 112. The incoming traverser 112 classifies the vehicle 100 according to its specifications, and
a to 114e.

The storage conveyors 114a to 114e carry the incoming traverser 11
Align and transport the vehicle 100 supplied by 2. And in this example, the storage conveyors 114a to 114e
Vehicle 100 because there are five storage conveyors
It can be classified into two types and transported separately.

On the other hand, the storage conveyors 114a to 114e are connected to the unloading traverser 116. The unloading traverser 116 pulls out the work at the head of any of the storage conveyors 114a to 114e and places it on the unloading conveyor 118. Then, the carry-out conveyor 118 carries the vehicle 100 into the assembly line which is the next process.

According to this example, the vehicle 100 to be carried into the assembly line can be controlled depending on which of the storage conveyors 114a to 114e the carry-out traverser 116 takes out the vehicle 100 from. The loading traverser 112 and the storage conveyor 1
14, the operator 120 controls the unloading traverser 116 etc.
I was operating 122.

[Problems to be Solved by the Invention] As described above, even in the conventional work sorting apparatus,
The workpieces can be rearranged in the order required by the assembly line. However, the operation of the conventional device has become extremely difficult due to the fragmentation of the vehicle specifications accompanying diversification of user needs.

That is, in the conventional apparatus shown in FIG. 6, the selection of the vehicle 100 to be carried out to the assembly line is limited to the vehicle 100 at the head of each of the storage conveyors 114a to 114e. Therefore, in this example, the vehicle 100 to be carried out to the assembly line must be selected from the five vehicles 100.

If the number of storage conveyors is increased, the range of selection is increased accordingly. However, it is practically impossible to allocate one storage conveyor to all combinations of subdivided work specifications. Therefore, in reality, a compromise process such as allocating one storage conveyor for works having specifications with a small number of productions to some extent has been indispensable.

Further, in the conventional apparatus, since the operator sets the conditions, it is difficult to make a determination by combining all of the constraints to be considered. That is, when the specifications are subdivided, there are cases where the specifications are defined in various combinations, such as "left-hand drive vehicles with a cooler". Is very difficult.

Furthermore, the condition is extremely severe for a work with a special specification. For example, there is a condition such as "open 15 middle 4WD vehicles". In this example, it is necessary to remember the specifications of the work carried out over the past 15 vehicles. As the specifications of the work have been diversified in this way, there has been a strong demand that the optimum work rearrangement be performed automatically and that the unloading order be in accordance with the requirements of the assembly line.

Japanese Patent Application Laid-Open No. Sho 62-161618 discloses the use of a storage conveyor to perform leveling processing for vehicle loading. Japanese Patent Laid-Open Publication No. Sho 63-163 discloses a technique in which a loop-shaped buffer is provided in the middle of a line, where the work is circulated and a desired work is sequentially taken out.
No. 288805. However, in the method of circulating the work in a loop, it is difficult to adapt to a large work such as a vehicle, and it is not possible to determine whether there is a work to be put at the head of a plurality of storage conveyors, Since all the vehicles must always be circulated in a loop, it takes a very long time to select the corresponding work, which is not applicable to applications such as the present invention.

The present invention has been made in view of the above-described problems, and has as its object to provide a work rearranging apparatus that can carry out works in a desired order even if the number of storage conveyors is small.

Means for Solving the Problems According to the present invention, a work supply traverser that receives a work supplied from a previous process and distributes the work and a work distributed by the carry traverser are respectively received and arranged in the receiving order. A plurality of storage conveyors to be transported, a work traverser for sequentially pulling out the first work of any of the storage conveyors and carrying out the work to the next process, and a work for receiving the work of the work traverser and returning the work to the carry-in traverser. Conveyor and
While receiving and storing the work to be unloaded from the unloading traverser, a buffer line that can be unloaded independently of the timing at which the stored work is received, and the number of works seated on the buffer line. The number of occupied works to be detected and the work loading / unloading order are determined based on the production plan, and it is determined whether the work to be carried out is at the head of any of the plurality of storage conveyors. If it does not exist at the head, it searches for positions distant from the head sequentially to detect the corresponding work that is closest to the head, and returns the preceding work of the storage conveyor where the detected work exists to return to the conveyor. The traverser that controls the unloading traverser and detects the presence of the buffer line detected by the Depending on the number, it obtains a margin time which buffer line can carry the work without receiving a workpiece,
Control means for limiting a range for searching for a work to be unloaded when the corresponding work does not exist at the beginning of any of the storage conveyors to a range capable of being unloaded from the storage conveyor within the extra time. I do.

[Operation] The work rearranging apparatus according to the present invention has the above-described configuration, and determines whether the work to be carried out is at the head of a plurality of storage conveyors. If it is not at the head, it is searched in order from the side closest to the head, such as the second or third. In this way, the storage conveyor having the corresponding work at the position closest to the head is detected. Then, the unloading traverser returns the preceding work of the storage conveyor where the corresponding work exists to transport the work to the return conveyor. Then, the work can be returned to the carry-in traverser by the return conveyor.

Therefore, no matter where the work to be carried out is located on the storage conveyor, the work can be carried out by the carry-out traverser, and the work can be optimally carried out in response to a request of the next line. Therefore, the leveling accuracy is not restricted by the number of storage conveyors.
A highly accurate leveling can be achieved.

Further, a buffer line for storing the unloaded work is provided, so that the work can be unloaded from the buffer line to the next process even when the preceding work is being returned. And
According to the present invention, according to the number of occupied works of the buffer line detected by the occupied work number detecting means, a margin time in which the buffer line can carry out the work without accepting the work is obtained, and the time is provided at one of the storage conveyors. The range for searching for a work to be carried out when there is no corresponding work is limited to a range in which the work can be carried out within the extra time. Therefore, even if the preceding work return process is performed as described above, it is possible to reliably prevent a situation in which the input of the work to the next process is stopped.

[Example] Hereinafter, a work rearranging apparatus according to the present invention will be described.
This will be described with reference to the drawings.

Basic Configuration Example FIG. 1 is a configuration diagram showing a basic configuration (a configuration excluding a buffer line) of the present invention, and in this example, a vehicle carried out of a painting factory in an automobile production line.
10 are rearranged in a desired order and carried out to an assembly plant.

That is, the vehicle 10 from the painting factory is
Is supplied to the carry-in traverser. The carry-in traverser 14 classifies the traversers into five according to the specifications of the vehicle, and carries them into one of the five storage conveyors 16a to 16e. The storage conveyors 16a to 16e align and hold the loaded vehicle 10 and transport it, similarly to the above-described conventional example.

The tip of each of the storage conveyors 16a to 16e is connected to an unloading traverser 18, and the unloading traverser is connected to one of the leading vehicles 10 of the storage conveyors 16a to 16e.
Pull out. Then, the vehicle 10 carried out by the carry-out traverser 18 is carried on the carry-out conveyor 20 and carried out to the assembly factory.

Here, a characteristic of this basic configuration example is that a return conveyor 22 that connects the carry-out traverser 12 and the carry-in traverser 14 is provided. That is, the return conveyor 22 receives the vehicle 10 on the carry-out traverser 18 and conveys it to the carry-in traverser 14. Therefore, it is possible to return the leading vehicle of the storage conveyor 16 to the rear end of the storage conveyor 16 again without taking it out.

Therefore, when the vehicle 10 not at the head of the storage conveyors 16a to 16e is to be carried out to an assembly factory, the vehicle to be carried out is required.
If all the vehicles 10 preceding the vehicle on the storage conveyor where the 10 exists are returned by the return conveyor 22, the desired vehicle 10 can be carried out toward the assembly factory.

All such rearrangement operations of the vehicle 10 are automatically performed by the control unit. For this reason, in the work sorting apparatus of this embodiment, the loading conveyor 12
Antenna 30 as a means to recognize the specifications of the vehicle above
have. Then, the result detected by the antenna 30 is supplied to the vehicle specification recognition unit 32, where the specification of the vehicle 10 is recognized.

Therefore, in order to recognize such vehicle specifications, a storage unit with a transmission / reception device called an "ID tag" is attached to the vehicle 10, and all necessary vehicle specifications are stored in the ID tag. Then, the antenna 30 receives the electromagnetic wave transmitted from the ID tag, and the vehicle specification identifying unit 32 decodes the electromagnetic wave to recognize the vehicle specification. Various types of such a vehicle specification recognition system such as an optical method have been proposed, and can be appropriately selected depending on the condition of the equipment.

In this way, information on the incoming vehicle 10 recognized by the vehicle specification recognition unit 32 is supplied to the leveling operation control computer 40. This leveling operation control computer
40 manages the specifications and the like of the vehicles 10 to be carried in based on the production plan in the assembly plant, and the vehicles 10 to be carried into the assembly plant by the unloading conveyor 20 based on the data on the production ratio of each vehicle 10. Control the loading order.

Therefore, the leveling operation control computer 40 controls the carry-in traverser 14 based on the specifications of the carry-in vehicle 10 supplied from the vehicle specification identifying unit 32, and transfers the carry-in vehicle 10 to any of the desired storage conveyors 16a to 16e. Supply.

On the other hand, the leveling arithmetic control computer 40 determines the vehicle to be put into the assembly line, takes it out of the storage conveyors 16a to 16e of the vehicle 10 of the specifications, and controls the unloading traverser 18 to unload it to the assembly line by the unloading conveyor 20. Control.

The flow of the operation in the leveling operation control computer 40 will be described with reference to FIG. Here, the vehicle arrangement file 42 is provided in the leveling operation control computer 40 and stores the arrangement of vehicles on the storage conveyors 16a to 16e.

First, the control of the loading process will be described. When the arrival (S10) of the vehicle 10 at the loading conveyor 12 is detected,
In accordance with a signal from the antenna 10, the vehicle specification data is fetched via the vehicle specification recognition unit 32 (S12). Then, according to the vehicle specifications, the vehicle 10 is transferred to any storage conveyor 16a.
Decide whether to carry in to ~ 16e. Here, since there are only five storage conveyors 16, it is difficult to completely classify each specification, and a somewhat compromised classification is performed (S1
3).

Then, when the storage conveyor 16 to be loaded is determined in this way, a control signal is sent to the loading traverser 14 and the vehicle 10 is loaded into the determined storage conveyor 16. Then, the vehicle arrangement file 42 is updated with the data of the vehicle introduction (S15), and the contents of the vehicle arrangement file 42 are always kept accurate.

By repeating such processing, the vehicles 10 carried in from the painting factory can be classified based on the specifications of the vehicles and held in the plurality of storage conveyors 16.

On the other hand, the carry-out of the vehicle 10 to the assembly factory by the carry-out conveyor 20 is performed in accordance with the calculated vehicle carry-out order based on a leveling condition in accordance with a predetermined production plan. Therefore, when the unloading of one vehicle 10 is completed (S20), the search position is initialized to determine the initial search position of the vehicle list file 42 (S21). This initial position is determined so as to be one of the leading vehicles of the storage conveyor 16. Then, the vehicle arrangement file 42 is searched at this search position, and the specification of the vehicle is recognized (S22). The specifications are, for example, the color of the vehicle, the distinction between the left handle and the right handle, and the destination.

Next, it is determined whether the search has been performed for all positions (S2
3) If the search has not been completed, the search position is updated (S24). This update is for storage conveyor 1
Move backward sequentially from the beginning in 6. Then, after confirming whether there is a vehicle at the position where the specification is recognized in S22 (S25), it is determined whether the vehicle satisfies the leveling condition (S26).

If the vehicle does not satisfy the leveling condition, the process returns to S22 because the vehicle at the next position must be determined. On the other hand, if the leveling condition is satisfied, this is determined as the unloading vehicle.

Since the search of all the positions is completed in S23, there is no corresponding vehicle in the storage conveyor 16, and a warning (alarm) is issued (S28).

In this way, when the vehicle 10 to be carried out is determined, it is determined whether the vehicle 10 to be carried out is at the head of the storage conveyor 16 (S29). If the corresponding vehicle 10 is not at the head of the storage conveyor 16, the leading vehicle 10 in the storage conveyor 16 is pulled out by the unloading traverser 18 and returned to the conveyor.
Transport to 22.

Then, the return conveyor 22 transports the supplied vehicle to the carry-in traverser 14, and the carry-in traverser 14 carries in the vehicle 10 sent from the return conveyor 22 to the end of the original storage conveyor 16 from which the vehicle 10 was carried out ( S30).

In addition, the arrangement of vehicles in the storage conveyor 16 is changed by the return of the leading vehicle, so that the vehicle arrangement file 42 is updated (S31). By repeating this process, the type of vehicle 10 to be carried out can be stored in the storage line.
16 can be brought to the beginning.

If the vehicle 10 that wants to perform such a return or unload from the beginning was the head of the storage conveyor 16,
The unloading traverser 18 withdraws the vehicle 10,
It is carried out to the assembly plant by the carry-out conveyor 20 (S3
2). In addition, because the row of vehicles is changed by the unloading of the vehicle 10, the content of the row of vehicle file 42 is updated (S33).

By repeating such processing, a desired vehicle 10 can be carried out to an assembly factory even when the specifications are various and the number of storage conveyors 16 is far exceeding the number. Therefore, very precise leveling processing can be performed, and work efficiency in an assembly factory can be improved.

Further, in this embodiment, in determining the storage conveyor 16 to be carried in, classification based on the specifications of the vehicle 10 is performed. Therefore, the arrangement of vehicles in the storage conveyor 16 is based on the specifications of the vehicle 10 to some extent. Therefore, when the operator wants to manually perform rearrangement control for some reason, the operator can determine the arrangement of the vehicles 10, and there is no problem in the work.

In this embodiment, since the specification of the vehicle specification uses a “remote ID” system that uses an ID tag, an electromagnetic antenna 30, and the like, the degree of freedom in setting the specification is very large, and it is visually determined such as a destination. Impossible specifications can also be grasped.

On the other hand, in the above-described embodiment, the storage conveyor
In 16a to 16e, the sorting based on the classification based on the specification of the vehicle is used. However, the present invention is not limited to this, and the vehicle 10 can be randomly sorted into the vehicle storage conveyor 16 without performing any classification. That is, since the return conveyor 22 exists, even if there is any type of vehicle at the head of the storage conveyor 16, this does not constitute a condition for the type of the unloading vehicle 10. This is because vehicles in any of the storage conveyors 16a to 16e can be carried out.

If the transportation of the vehicle 10 on the storage conveyor 16 is performed irrespective of the type of the vehicle, the operation of the loading traverser 14 and the storage of the vehicle 10 on the storage conveyor 16 are not restricted at all. it can.

Embodiment Next, FIG. 3 shows a configuration diagram of an embodiment of the present invention. A feature of this embodiment is that a buffer line 50 is provided.

The buffer line 50 is provided at an intermediate portion of the unloading conveyor 20 and stores the vehicle 10 conveyed by the unloading conveyor 20 to some extent. And
By providing the buffer line 50, when the unloading by the unloading traverser 18 is stopped by unloading the vehicle 10 by the return conveyor 22, the unloading vehicle 10 stored in the buffer line 50 is unloaded. Stop of unloading of the vehicle 10 toward can be prevented.

For this purpose, the apparatus of the second embodiment has an entrance-side limit switch 52 at the entrance of the buffer line 16 and an exit-side limit switch 54 and a counter 56 at the exit. Are supplied to the leveling operation control computer 40.

Then, the leveling control computer 40 takes into account the number of stocked vehicles 10 in the buffer line 50, and
Control the vehicle withdrawal at.

Therefore, the leveling control computer in this embodiment
Operation 40 will be described.

First, the problem required to pull out the leading vehicle of the storage conveyors 16a to 16f to the unloading conveyor 22 is (drawing time to the traverser 18 + moving time in the traverser 18). However, vehicles from the traverser 18 to the unloading line 20
The time to unload 10 is to move the next vehicle 10 to the traverser 18
Can be overlapped with the withdrawal time,
It can be excluded from the required time described above.

And the withdrawal time to this traverser 18 is Tp,
The moving time in the traverser 18 is T _t × S1. Here, the moving time in the traverser 18 is expressed in this manner because the time required for transport to the unloading conveyor 22 differs depending on the storage conveyors 16a to 16f, and the time T _t
Is the time required to move one interval (one span) of the storage line 16 in the traverser 18, and S1 is the number of spans required to move to the unloading conveyor 20 at this time.

In the example of FIG. 3, the number of spans S1 is as follows for the unloading of each vehicle 10 on the storage conveyor 16.

16a = 3,16b = 2,16c = 1,16d = 0,16e = 1,16f = 2 On the other hand, the time required to send the leading vehicle 10 of each storage conveyor 16 to the return conveyor 22 is determined by the traverser described above.
18 withdrawal time Tp and traverser 18 moving time T _t ×
It is the sum of S2. Here, S2 is a moving span from each storage conveyor 16 to the return conveyor 22, and the number of spans is as follows.

16a = 6,16b = 5,16c = 4,16d = 3,16e = 2,16f = 1 Under such a premise, the time required to pull out the vehicle 10 at each part in the storage conveyor 16 is calculated as follows. As shown in the figure. Here, when the vehicles in the second and subsequent rows are carried out, the time for carrying out the vehicles and the time for carrying them to the return conveyor 22 are added.

On the other hand, in the buffer line 50, the unloading traverser 18
The capacity of the buffer line 50 to determine how many vehicles can be carried out to the assembly plant without accepting vehicles from the vehicle is determined by the maximum number of storages Nmax in the buffer line 50 (= buffer line 50
The difference Nmax-Nmin between the transport path length of the vehicle 10 / the pitch of each vehicle 10 and the running number Nmin (= the transport path length of the buffer line 50 / the transport speed of the buffer line 50 × T) is the capacity of the buffer line 50. is there. Here, T is a cycle in which the vehicle 10 is carried into an assembly factory which is a post-process, that is, a production line tact.

N (Nmin <n ≦ Nmax) vehicles in the buffer line 50
Assuming that the vehicle 10 is present, even if the vehicle 10 is not unloaded from the storage conveyor 16 during (n−Nmin) × T, no problem occurs in the assembly factory which is a subsequent process.

Therefore, the time of (n−Nmin) × T can be regarded as a margin time.

Since there is such a relationship, assuming that the unloading time of the vehicle 10 at various locations on the storage line 16 is Tij, when the vehicle 10 at the site satisfying the following relationship is unloaded, the There is no shortage, and there is no problem in carrying out to the subsequent process.

That is, assuming that the number of occupied vehicles in the buffer line 50 is n, if the surplus number nij is defined as nij = Tij / T + Nmin, then n> nij may be satisfied. Here, the subscript ij represents the vehicle in the j-th column of the i-th storage line.

Then, in the leveling control computer 40 according to the present invention, the leveling condition is determined, and the above-mentioned withdrawable condition is added. Therefore, the rearrangement of the vehicle 10 can be achieved without causing any trouble in the subsequent process.

The above-mentioned n> nij is determined by the leveling control computer 40.
The calculation may be performed at any time in the calculation and determined as an accurate value, or may be stored as a predetermined value. In addition, both the leveling condition and the withdrawable condition may be prioritized, and it may be determined which one is prioritized according to the situation at that time.

Furthermore, from the viewpoint of giving priority to the one that is easier to calculate, it is better to precede the determination of the withdrawable condition. FIG. 5 shows a flowchart in the case where priority is given to the determination of the withdrawable condition.

In this processing, first, the number of seats n in the buffer line 50 is fetched (S51), and then ij satisfying n> nij is extracted (S52). Vehicle 1 extracted by this
The leveling condition is determined for 0 (S53).

When the vehicle to be determined is specified in this way, it is determined whether or not there is a vehicle that satisfies the leveling condition (S54). If there is a vehicle that satisfies the leveling condition, the vehicle is carried out (S55). If there is no corresponding vehicle, an alarm process is performed (S56), and this is repeated.

According to such a flowchart, it is possible to determine the leveling condition after first determining the withdrawable condition. The determination of the leveling condition here (S53)
Is the same as the leveling condition determination in the first embodiment described above.

Further, in FIG. 5 described above, it is not assumed that the number of stocked vehicles in the buffer line 50 where n ≦ Nmin is very small. This is because the leveling condition may be set so that such a situation does not occur.

As described above, according to the work rearranging apparatus in the embodiment, since the buffer line 50 is provided, even if the returning operation of the vehicle by the return conveyor 22 is performed, the unloading of the vehicle to the subsequent process is not stopped, The leveling accuracy in the post-process can be improved.

[Effects of the Invention] As described above, according to the work sorting apparatus according to the present invention, a work that is not at the head of the storage conveyor can be carried out. Therefore, it is possible to carry out the work based on a very wide variety of specifications without increasing the number of storage conveyors, and to perform highly accurate leveling processing. In addition, since the equipment for this is only to provide a return conveyor, this can be achieved at low cost. In particular, in the present invention, a buffer line is provided, and a range for searching for a work to be carried in the storage conveyor is determined according to the number of work present in the buffer line. Therefore, even if the preceding work is returned,
It is possible to reliably prevent a situation where the work input to the next process is stopped.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a configuration of a work rearranging apparatus according to a basic configuration example showing a basic configuration of the present invention, FIG. 2 is a flowchart for explaining the operation of the basic configuration example, FIG. Is a schematic configuration diagram showing the configuration of the embodiment, FIG. 4 is an explanatory diagram for explaining the operation time in the embodiment, FIG. 5 is a flowchart for explaining the operation of the embodiment, FIG. 1 is a schematic configuration diagram illustrating a configuration of a work rearranging apparatus. 10 Vehicle 14 Carry-in traverser 16 Storage conveyor 18 Carry-out traverser 30 Antenna 32 Vehicle specification recognition unit 40 Leveling arithmetic control computer (control means)

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-61-207277 (JP, A) JP-A-63-200948 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B65G 43/00-43/08

Claims (1)

(57) [Claims] 1. A work supplied from a previous process is received,
A work carry-in traverser for distributing the work, a plurality of storage conveyors for receiving the works distributed by the carry-in traverser, respectively, and arranging and conveying the works in a receiving order, and sequentially pulling out any head work of the storage conveyor. An unloading traverser for unloading to the next process, a return conveyor for accepting the work of the unloading traverser and transporting it to the importing traverser, and receiving and storing the work to be unloaded from the unloading traverser and storing the work. A buffer line that can be unloaded independently of the timing at which a workpiece is received, a number of occupied workpieces detecting means that detects the number of workpieces occupying the buffer line, and a loading / unloading order of workpieces based on a production plan. The work to be carried out is Judge whether it is at the head of any of the storage conveyors, and if the relevant work does not exist at the head, search for positions distant from the head sequentially and detect the relevant work located closest to the head, and detect The unloading traverser is controlled so as to transport the preceding work of the storage conveyor in which the corresponding work is present to the return conveyor, and the buffer line is determined according to the number of occupied works of the buffer line detected by the occupied work number detecting means. Finds a time to allow the workpiece to be unloaded without accepting the workpiece, and allows a range to search for a workpiece to be unloaded when the corresponding workpiece does not exist at one of the storage conveyors within the extra time. Control means for limiting the range to a specific range.