JP2010170333A - Mixed-flow production line - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology that increases the productivity of mixed-flow production. <P>SOLUTION: When a cycle time Ta for a first kind elapses from a preceding automatic guided vehicle 12 carrying the first kind, a truck start control unit 22 causes start, and when a cycle time Tb for a second kind elapses from a preceding automatic guided vehicle carrying the second kind, the control unit starts the automatic guided vehicle carrying the second kind. As a result, the kind with a short operating time can be conveyed in a short cycle time, and the kind with a long operating time can be conveyed in a long cycle time, resulting in greatly increased productivity. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a mixed flow production line capable of multi-model production.

  In recent years, a mixed flow production line that produces multiple models on a single production line has been adopted (see, for example, Patent Document 1 (FIG. 1)).

Patent document 1 is demonstrated based on the following figure.
FIG. 5 is a diagram for explaining the basic configuration of a conventional mixed flow production line. A type A workpiece 102 and a type B workpiece 103 are appropriately sent continuously from the left to the right at a constant speed by a conveyor 101. Workers 104 to 109 are arranged along the conveyor 101.

  The worker 104 performs work on the A type work 102 and the B type work 103. The worker 105 performs work on the A type workpiece 102. The workers 106 and 107 perform work on the A type work 102 and the B type work 103. The worker 108 performs work on the B type work 103. The worker 109 works on the A type workpiece 102 and the B type workpiece 103.

When the B-type work 103 reaches the B-work identification unit 111, the B-type work 103 is moved from the conveyor 101 to the B-type dedicated machine 113 as indicated by an arrow 112, and is subjected to predetermined machining. After processing, it is returned to the conveyor 101 as indicated by an arrow 114.
Similarly, when the A-type work 102 reaches the A-work identification unit 115, the A-type work 102 is moved from the conveyor 101 to the A-type dedicated machine 116 and subjected to predetermined machining. After processing, it is returned to the conveyor 101.

  As described above, various types of production can be performed with one conveyor 101. On the conveyor 101, the A-type work 102 or the B-type work 103 is successively sent at a constant speed.

By the way, the worker 104 performs work on the A-type work 102 and the B-type work 103. The work applied to the A-type work 102 is simple and requires a short time, and the work applied to the B-type work 103 is complicated and may take a long time.
As a result, the conveyance speed of the conveyor 101 needs to be reduced in accordance with the B type workpiece 103, and the productivity is lowered accordingly.

  In mixed-flow production, technology that increases productivity is required.

JP-A-8-252748

  This invention makes it a subject to provide the technique which can raise productivity more in mixed flow production.

The invention according to claim 1 is a first taxiway laid on the floor along the processing flow line of the first model,
A second taxiway laid on the floor along the flow line of the second model so as to overlap the first taxiway except for the individual taxiway;
An unmanned carriage that is guided to the second taxiway to convey the second model or that is guided to the first taxiway to convey the first model;
Using the unit operating time as the numerator, calculate the cycle time of the first model using the production amount of the first model per unit operating time as the denominator, and using the unit operating time as the numerator, calculate the output of the second model per unit operating time. A calculation unit for calculating the cycle time of the second model as a denominator;
The unmanned cart loaded with the first model from the entrance of the first taxiway that also serves as the entrance of the second taxiway, and the cycle time of the first model elapsed from the unmanned cart loaded with the preceding first model A vehicle start control unit for starting the unmanned cart loaded with the second model when the cycle time of the second model has elapsed from the unmanned cart loaded with the preceding second model, A mixed flow production line is provided.

  The invention according to claim 2 calculates the cycle time of the first model using the unit operating time as the numerator, the production amount of the first model per unit operating time as the denominator, and the unit operating time as the numerator. The first model except the step of calculating the cycle time of the second model with the production amount of the second model as the denominator, the first guideway laid on the floor along the processing flow line of the first model, and the individual guideway A second guideway laid on the floor along the processing flow line of the second model so as to overlap with the guideway, and is guided by this second guideway to carry the second model or to the first guideway For the unmanned cart that is guided and transports the first model, the first model that precedes the unmanned cart loaded with the first model from the entrance of the first taxiway that also serves as the entrance of the second taxiway Issued when the cycle time of the first model has elapsed from the unmanned cart loaded with Is allowed, the unmanned carriage carrying the second type, characterized by having a a step of starting when prior to the unmanned carriage carrying the second type are of a second type cycle time has elapsed.

  In the invention which concerns on Claim 1, the unmanned cart was employ | adopted for the movement of a workpiece | work. Conventional conveyors tend to feed workpieces continuously at substantially equal pitches. In this regard, since the unmanned carriage is employed in the present invention, the intervals between the unmanned carriages can be uneven. Although the work time varies depending on the model, this difference can be absorbed at intervals between unmanned carts.

  As a result, a model with a short work time can be transported with a short cycle time, and a model with a long work time can be transported with a long cycle time, greatly improving productivity.

  In the invention according to claim 2, the cycle time of the first and second models is calculated, and the cycle time of the model has elapsed from the unmanned cart with the preceding model on the unmanned cart with the respective model. Sometimes start. Since the carriage is started based on the calculated cycle time in advance, the productivity can be increased without the need to wait for the processing of the preceding model and the adjustment of the conveyance speed.

It is laying drawing of the 1st taxiway concerning the present invention. It is a laying figure of the 2nd taxiway concerning the present invention. It is laying drawing of the 3rd taxiway concerning the present invention. It is a basic lineblock diagram of the mixed flow production line concerning the present invention. It is a figure explaining the basic composition of the conventional mixed flow production line.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the first guide path 13 for guiding the unmanned carriage 12 on which the first work 11 as the first model is placed is placed on the floor 14 along the processing flow line of the first work 11. The lead-in line-shaped first standby path 15 provided at the entrance of the first guide path 13, the first individual guide path 16 unique to the first work 11, and the empty carriage return guide path 17 are included. The unmanned carriage 12 is an automatic traveling carriage that detects the first guiding path 13 laid on the floor 14 and travels while controlling the traveling direction by itself so as not to deviate from the first guiding path 13. It is called AGV.
Then, the first work 11 is mounted on the unmanned carriage 12 as indicated by the white arrow 18, and after the predetermined work is performed, the first work 11 is paid out by the white arrow 19.

For example, 83 units of the first work 11 are produced per day. The operating time per day is 15 hours for the total of 2 teams, and if the operating efficiency for small troubles is assumed to be 97%, it will be 52380 (seconds) according to the calculation of 15 hours × 0.97 × 60 × 60 = 52380. .
Assuming that the cycle time of the first workpiece is Ta, the calculation is Ta = (daily operation time) / (daily production amount) = 52380/83 = 631, resulting in 631 seconds.

  The calculation described above is performed by the calculation unit 21, and the cart start control unit 22 that has obtained this information starts the unmanned cart 12 every Ta (631 seconds in this example). Since the unmanned carriage 12 moves at a constant speed, in principle, the unmanned carriage 12 on which the first work 11 is placed travels along the first guide path 13 at intervals corresponding to Ta.

Next, the second guiding path 24 will be described.
As shown in FIG. 2, the second guide path 24 for guiding the unmanned carriage 12 on which the second workpiece 25 as the second model is placed is provided on the floor 14 along the processing flow line of the second workpiece 25. The lead-in line-shaped second standby path 26 provided at the entrance of the second guide path 24, the second individual guide path 27 unique to the second work 25, and the empty carriage return guide path 17 are included. Most of them overlap with the first taxiway 14.
That is, the second work 25 is also mounted on the unmanned carriage 12 as indicated by the white arrow 18 and is paid out by the white arrow 19.

For example, 181 units of the second work 25 are produced per day. As described above, the operating time of one day is 52380 (seconds).
Assuming that the cycle time of the second workpiece is Tb, Tb = (daily operation time) / (daily production amount) = 52380/181 = 289, which is 289 seconds.

  The calculation described above is performed by the calculation unit 21, and the cart start control unit 22 having obtained this information starts the unmanned cart 12 every Tb (289 seconds in this example). Since the unmanned carriage 12 moves at a constant speed, in principle, the unmanned carriage 12 on which the second workpiece 25 is placed travels along the second guide path 24 at intervals corresponding to Tb.

Next, the third guiding path 31 will be described.
As shown in FIG. 3, the third guide path 31 for guiding the unmanned carriage 12 on which the third work 29 as the third model is placed is formed on the floor 14 along the processing flow line of the third work 29. The lead-in line-shaped third standby path 32 provided at the entrance of the third guide path 31, the third individual guide path 33 unique to the third work 29, and the empty carriage return guide path 17 are included.
That is, the third work 29 is also mounted as indicated by the white arrow 18 and is paid out by the white arrow 19. Most of them overlap with the first taxiway 14.

For example, 64 units of the third work 29 are produced per day. As described above, the operating time of one day is 52380 (seconds).
Assuming that the cycle time of the third workpiece is Tc, Tc = (daily operation time) / (daily production amount) = 52380/64 = 818, which is 818 seconds.

  The above calculation is performed by the calculation unit 21, and the cart start control unit 22 that has obtained this information starts the unmanned cart 12 every Tc (818 seconds in this example). Since the unmanned carriage 12 moves at a constant speed, in principle, the unmanned carriage 12 on which the third workpiece 29 is placed travels on the third guide path 31 at intervals corresponding to Tc.

  By superimposing FIGS. 1 to 3, the mixed flow production line 10 shown in FIG. 4 can be obtained. In this way, the first to third taxiways 13, 24, 31 are overlapped to realize space saving of the production line, and other than the dedicated equipment for each model can be shared, Capital investment can be reduced. The mixed flow production line 10 may be a production line that mixes three models as in the embodiment, a production line that mixes four or more models, or a production line that mixes two models.

A production line that mixes two models has the following configuration.
That is, the mixed flow production line 10 includes the first guide path 13 except for the first guide path 13 and the individual guide paths 16 and 27 laid on the floor along the processing flow line of the first model (first workpiece 11). And a second guide path 24 laid on the floor along the flow of processing of the second model (second work 25), and the second model is guided by the second guide path 24 to convey the second model. Or the unmanned carriage 12 that is guided to the first guide path 13 and transports the first model, and the cycle of the first model with the unit operating time as the numerator and the production amount of the first model per unit operating time as the denominator. The calculation unit 21 that calculates the time Ta, calculates the cycle time Tb of the second model using the unit operating time as the numerator and the production amount of the second model per unit operating time as the denominator, and also serves as the entrance of the second taxiway From the entrance of the first taxiway The unmanned carriage 12 carrying the first model is started when the cycle time Ta of the first model has elapsed from the unmanned carriage 12 carrying the preceding first model, and the unmanned carriage carrying the second model is preceded by And a cart start control unit 22 that starts when the cycle time Tb of the second model elapses from the unmanned cart on which the second model is mounted. The unit operating time is the total time from the start of production on the production line to the end of the production line (one day for a day, half day for a half day), and the time when the production line is temporarily stopped. The actual operating time when the production line is actually operating is different.

  First, in the present invention, the unmanned carriage 12 is employed for moving the workpiece. With a conventional conveyor, the workpieces can be fed continuously at a substantially equal pitch. In this respect, since the unmanned carriage 12 is employed in the present invention, the intervals between the unmanned carriages 12 can be uneven. Although the work time varies depending on the model, this difference can be absorbed at intervals between the unmanned carriages 12.

  As a result, a model with a short work time can be transported with a short cycle time, and a model with a long work time can be transported with a long cycle time, greatly improving productivity. This is because the required number of personnel in the line process is calculated by dividing the total man-hours for that model in that line process by the cycle time of that model. A large number of models, that is, a number corresponding to a model with a short cycle time is required, and for other models, each worker has some waiting time. On the other hand, according to the present invention, personnel can be allocated with the cycle time for each model, so that the waiting time for workers is saved and productivity is improved.

  In addition, the processing of the processing lead does not stop in the narrow sense of machining, but refers to general operations included in the production process such as assembly and inspection.

  The mixed flow production line of the present invention is suitable for multi-model mixed flow production.

  DESCRIPTION OF SYMBOLS 10 ... Mixed flow production line, 11 ... 1st model (1st workpiece | work), 12 ... Unmanned cart, 13 ... 1st taxiway, 21 ... Calculation part, 22 ... Carriage start control part, 24 ... 2nd taxiway, 25 ... Second model (second workpiece), Ta ... cycle time of the first workpiece, Tb ... cycle time of the second workpiece.

Claims (2)

A first taxiway laid on the floor along the processing flow line of the first model;
A second taxiway laid on the floor along the processing flow line of the second model so as to overlap the first taxiway except for the individual taxiway;
An unmanned carriage guided to the second taxiway to convey the second model or guided to the first taxiway to convey the first model;
Using the unit operating time as the numerator, calculate the cycle time of the first model using the production amount of the first model per unit operating time as the denominator, and using the unit operating time as the numerator, calculate the production amount of the second model per unit operating time. A calculation unit for calculating the cycle time of the second model as a denominator;
The unmanned cart loaded with the first model from the entrance of the first taxiway that also serves as the entrance of the second taxiway, and the cycle time of the first model passed from the unmanned cart loaded with the preceding first model A vehicle start control unit for starting the unmanned cart loaded with the second model when the cycle time of the second model has elapsed from the unmanned cart loaded with the preceding second model, A mixed flow production line characterized by Using the unit operating time as the numerator, calculate the cycle time of the first model using the production amount of the first model per unit operating time as the denominator, and using the unit operating time as the numerator, calculate the production amount of the second model per unit operating time. Calculating the cycle time of the second model as the denominator;
1st taxiway laid on the floor along the processing flow line of the first model, and laying on the floor along the process flow line of the 2nd model so as to overlap the first taxiway except for the individual taxiway A second taxiway,
For an unmanned carriage that is guided to the second taxiway and transports the second model or is guided to the first taxiway and transports the first model,
The unmanned cart loaded with the first model from the entrance of the first taxiway that also serves as the entrance of the second taxiway, and the cycle time of the first model passed from the unmanned cart loaded with the preceding first model And starting the unmanned cart loaded with the second model when the cycle time of the second model has elapsed from the unmanned cart loaded with the preceding second model. A feature of the unmanned cart start guidance control method.

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