JPS5827168B2 - Method for controlling the conveyance of goods using a conveyor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for controlling the conveyance of articles by a conveyor, and an object of the present invention is to transfer articles that have been randomly worked at a plurality of work positions to subsequent processes. The purpose is to be able to supply at intervals according to the throughput of the process.

Conventionally, in a device in which a plurality of article discharging devices for discharging articles onto a conveyor were arranged along the conveyance direction of the conveyor, the articles were transferred from the article discharging device to the conveyor at any time.
The present invention aims to solve the problems of the conventional art, in which there was a problem that the intervals between the objects flowing on the conveyor were too small, resulting in several objects being conveyed in groups, resulting in a temporary shortage of processing capacity in the subsequent process. In addition to providing storage areas for articles at each of the plurality of work positions arranged along the conveyance direction of the conveyor, the conveyor has a plurality of lengths corresponding to the processing capacity of the subsequent process. The system is divided into sections, and in sections where there are articles, transport from the previous section is stopped, and the removal of articles from buffers located within the sections is also stopped.

Hereinafter, an embodiment of the present invention will be described in which, in a conveyor that conveys a pallet with workpieces attached between a plurality of machine tools, the pallet that has been completely machined is transferred to a cleaning device by the conveyor at an interval according to the processing time of the cleaning device. The following describes the case of transporting to.

In FIG. 1, 1 is an endless chain conveyor that moves continuously, and a plurality of machine tools MA1 to MA8 are arranged along this conveyor 1.

The conveyor 1 is provided with stop positions S1 to S8 corresponding to each of the machine tools MAI to MA8, and stop positions SO and S9 are provided at the entrance and exit parts.

Stop members dO to d9 are disposed at each of the stop positions SO to S9 so as to be able to appear and retract, and the protrusion of the stop members causes the conveyor to
The pallets P transported by the pallets P are temporarily stopped at each stop position, and the arrival of the pallets P at the stop positions SO to S9 is confirmed by the operation of a limit switch (not shown).

Thus, the conveyor 1 is divided into nine small sections (1) to (19) by the stop members dO to d9.

RO to R9 are well-known pallet identification devices installed at each stop position SO to S9, which identify the arrangement state of the dogs attached to the side of each pallet based on, for example, the on-off output of a limit switch. The numbers of the pallets P stopped at the stop positions SO to S9 are read.

L1 to L8 are pallet loading and unloading devices that load and unload pallets P between machine tools MAI to MA8 and conveyor 1, and pallets) P stopped at stop positions 81 to S8 are pallet loading and unloading devices between machine tools MAI to MA8 and conveyor 1.
When the pallet P is to be machined by A1 to MA8, the pallet P is pulled onto the table A and machine tool M is used.
The pallets (P) which have been carried into AI to MA8 and processed by the machine tools MA1 to MA8 are received from the machine tools onto a table B which acts as a buffer area and are carried out onto the conveyor 1.

Reference numeral 2 denotes a loading station disposed at the front end of the conveyor 1. An operator attaches a workpiece to a pallet P at the loading station 2 and sends it to the conveyor 1.

Reference numeral 3 denotes a cleaning device disposed at the rear end of the conveyor 1, which cleans the pallets (hereinafter referred to as cleaning pallets) that have undergone all necessary machining by the machine tools MA1 to MA8.

Reference numeral 4 denotes a return conveyor, which returns the pallets ()P that have been stopped at the stop position S9 and which remain to be processed by the machine tools MA1 to MA9 to the stop position SO.

Furthermore, in order to convey the cleaning pallet Pe at intervals corresponding to the cleaning time of the cleaning device 301, the conveyor 1 is divided into a plurality of large sections 01 to G4 at approximately equal intervals for control purposes.

That is, the small sections 11 to I9 are divided into large sections G1 such that the time required for transporting the cleaning pallet Pe from one end of the large section to the other is approximately equal to the cleaning time of the washing device 301 times.
~ Grouped into G4.

The pallet identification devices RO to R9 and the like are each connected to a computer 6 via an interface 5 so as to exchange control signals with the computer 6.

In the storage device of the computer 6, a section status table as shown below is allocated that has an in-use flag and a cleaning pallet present flag corresponding to each of the small sections (1 to 9), and the in-use flag indicates that the corresponding small section is in use. When there is a cleaning pallet (Pe) in the corresponding small section, the cleaning pallet presence flag is set to "1" and stored.

The storage device also stores tables for groups indicating grouping into small sections 1 to I90 and large sections 01 to G4, as shown below.

Further, in the storage device, a conveyance control program (FIG. 2) for controlling the flow of pallets (P) conveyed on the conveyor 1 is stored.
is stored, and this program is executed at regular intervals.

Next, the operation of the above embodiment will be explained in the case where the pallet is located at the position shown in FIG.

According to the execution of the conveyance control program, first the stop position SO
It is determined whether or not the pallet (P) has arrived at the stop position SO.
Since the pallet P has arrived at , it is next determined whether the in-use flag of the small section 11 is "0"'.

In this case, the in-use flag for small section ■1 is "
1”, the program jumps and the pallet is placed at the stop position S1 corresponding to the first machine tool MAI)
If the in-use flag of sub-section ■1 is “0”, the in-use flag of sub-section ■1 is “1”.
'', a straight-line command is sent out, and this straight-forward command causes the stop member dO to move backwards) P is a small section ■1
will be transported.

Since the pallet P has arrived at the stop position S1, reading of the pallet number is then commanded and the pallet identification device R
The pallet number is read from 1. Next, whether or not this pallet (P) should be processed with the machine tool MAI is determined by the process chart that stores the number of the machine tool to which the pallet is to be carried in for each pallet number. It is determined based on.

Assuming that pallet P is to be processed by machine tool MAI, then table A of pallet loading/unloading device L1
In this case, since it is vacant, the in-use flag of small section The pallet number is stored in the A pallet area of the storage device.

Next, pallets are placed on table B of pallet loading/unloading device L1)
It is determined whether or not there is a pallet P, and since there is a pallet P on table B as shown in FIG. 1, it is determined whether or not the in-use flag of the small section (2) is "'O".

Since the in-use flag in the small section (2) is '0', it is then determined on the basis of the process chart whether this pallet is a washed pallet (Pe) that has been completely processed.

In this case, the number of the pallet on top of the pallet B is the pallet number stored when the pallet was carried onto the table A, and the one transferred to the B pallet area according to the movement of pallet P is read out.

Since the pallet on table B is a cleaning pallet Pe, the next small section 11. Pe belongs to the large section G1 to which the small section ■2 belongs. I2. The group I3 is searched from the table,
Searched small sections 11, I2. It is determined whether all the cleaning pallet presence flags of I3 are 0'' or not.

Since the cleaning pallet presence flag in the small section ■3 is 1'', it is jumped and the cleaning pallet Pe is not carried out to the small section ■2.

Next, stop position 88 corresponding to the eighth machine tool MA8
Since it is determined whether or not the check has been completed up to that part, it is determined whether or not the pallet (P) has arrived at the stop position S2 corresponding to the second machine tool MA2. It is determined whether there is a pallet (P) on table B of device L2, and since it is not, it jumps and moves to the next stop position S corresponding to the third machine tool MA3.
Stop position S where it is determined whether the pallet P has arrived at 3.
Since pallet P has arrived at No. 3, the pallet number is read and it is determined whether or not it should be processed by machine tool MA3. Since it is not, the in-use flag of small section I4 is set to "O". Since it is "O", it is determined whether this pallet is a cleaning pallet (Pe), and since it is a cleaning pallet, it is determined whether small sections ■3 and I4 belong to the same large section. Groups are determined based on the table.

Since small sections ■3 and 14 do not belong to the same large section, the next small section ■4 belongs to the small section I4 within the large section G2. I5
It is determined whether all the cleaning pallet present flags are "Ol+", and since they are "no", the cleaning pallet () Pe is not transferred to the small section (4).

Next, it is determined whether or not there is a pallet P on the table B of the pallet loading/unloading device L3, and if there is, it is determined whether the in-use flag of small section ■4 is "0" or not, and since it is "0", the cleaning pallet is ) It is determined whether or not it is Pe, and since it is not, a jump is made, the in-use flag of the small section (2) is set to "1", and the pallet P is carried out to the small section (2).

Stop position S4, table BK of pallet loading/unloading device L4
Since there is no U pallet P, it is jumped, and it is determined whether or not the pallet P has arrived at the stop position S5. Since it has arrived, the pallet number is read, and it is determined whether or not there is machining by the machine tool VMA8. Therefore, it is determined whether the in-use flag of small section ■6 is "0" or not, and since it is "O1+, it is determined whether or not it is a cleaning pallet. Since it is a cleaning pallet Pe, small sections ■5 and I6 have the same size. It is determined whether it belongs to the section or not, and since it is not, it is determined that the small section ■6 belongs to the large section G.
It is determined whether the cleaning pallet present flags of all the small sections within 3 (in this case, only the small section ■6) are "0" or not, and since "Ojj", the cleaning pallet present flag of the small section ■6 is set to "1". Set the cleaning pallet presence flag of small section ■5 to "ON," then set the in-use flag of small section I6 to 1,
After turning on the in-use flag of the small section ■5, a straight-ahead command is output.

In response to this straight forward command, the stop member d5 is moved backward, and the cleaning pallet ()Pe is transferred to the small section (6).

Since there is no pallet P in the table B of the pallet loading/unloading devices L5 to L8 and the stop positions 86 to s8, it is jumped, and then it is determined whether or not the check has been completed up to the stop position 88. Since it has been completed, the check is continued to the stop position. In S9, it is determined whether or not the pallet P has arrived, and since it has arrived, the pallet number is read and it is determined whether it is a cleaning pallet.

In this case, since the cleaning pallet) Pe is empty, it is determined whether the cleaning device 3 is empty or not, and if it is empty, a command to carry it into the cleaning device is sent, the stop member d9 is retreated, and the cleaning pallet) Pe is the cleaning device 3. will be transported to.

Then, the cleaning pallet presence flag and the in-use flag in the small section (2)9 are set to "0" and the program ends.

If the pallet that has arrived at the stop position S9 is not the cleaning pallet Pe, a return command is sent, and the pallet Pe is transferred to the return conveyor 4 and returned to the stop position SO.

As described above, in the present invention, a buffer area for storing articles is provided at each of a plurality of work positions arranged along the conveyance direction of the conveyor, and the length of the conveyor is adjusted according to the processing capacity of the subsequent process. The structure is divided into multiple sections with a number of sections, and in the section where the article is located, the transfer from the previous section is stopped, and the removal of the article from the buffer located within the section is also stopped, so that there are multiple work positions. Even if items that have been completed work are randomly delivered from the beginning, the items can be transported to the subsequent process at regular intervals depending on the processing capacity of the subsequent process, and if the processing capacity of the subsequent process is temporarily insufficient, This has the advantage of preventing articles to be transported to the process from occupying three bears and making it impossible for other articles to flow.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram showing the arrangement of a conveyor, machine tools, etc., and FIG. 2 is a diagram showing a conveyance control program. 1...Conveyor, 3...Cleaning device (post-process), 6...Computer, MA1 to MA8
...Machine tools, L1-L8...Pallet loading/unloading device (goods loading/unloading device), RO-R9...
・Pallet identification device, SO~S9...Stop position, 11~■9...Small section, 01~G8...
・・Large section (section), P・・・・Palette, Pe・
...Cleaning pallet (item).

Claims (1)

[Claims] 1. An article carrying-out device is disposed to carry out articles onto the conveyor from each of a plurality of working positions arranged along the conveyance direction of the conveyor, and articles are transferred from the plurality of working positions to a subsequent process via the conveyor. In the apparatus for conveying articles, buffers for storing articles are provided at each of the plurality of work positions, and the time required for conveying articles from one end of the section to the other on the conveyor is shortened in the subsequent process. Divide into multiple sections at approximately equal intervals so as to be approximately equal to the processing time, detect the presence or absence of an article in each section, and prevent the transfer of articles from the previous section to the section where the presence of an article is detected. 1. A method for controlling the conveyance of articles by a conveyor, characterized in that the conveyance of articles by a conveyor is simultaneously prevented from being carried out from a buffer at a working position located within a corresponding section.