JP2649462B2 - Work transfer method on assembly line - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembly line in which a workpiece is transported by a self-propelled transport member. The present invention relates to a work transfer method applied to a work.

[0002]

2. Description of the Related Art Conventionally, in an assembly line in which a manual work area where manual work is performed and an automatic work area where work is performed by an automatic machine are mixed, each work is transported by a self-propelled transfer member to perform manual work. It is known that work is performed while moving a transport member in an area, and work is performed with the transport member stopped in an automatic work area. In such an assembly line, a line tact, that is, an operation time in one process in a manual operation area is determined in accordance with a target production number, and a transfer speed and a transfer pitch of a work are determined based on the line tact. . In this case, since the work in the automatic work area can be performed in a relatively short time, the transfer member is restarted in the automatic work area after the end of the work with a waiting time of a difference from the line tact, and the preceding transfer is performed. The pitch between the members is set to the transport pitch determined as described above.

[0003]

However, a trouble occurs in an area where the transfer member is stopped and work is performed, such as an automatic work area, and restarting of the transfer member from the area is delayed, so that the subsequent transfer member is stopped. Once in the area upstream,
This stagnation remains even after recovery from the trouble, and delays the work on the downstream side of the area, and consequently does not reach the planned production number. In view of the above points, an object of the present invention is to provide a method of transporting a work that eliminates the above-described stagnation after recovery from a trouble and can recover a delay in work.

[0004]

In order to achieve the above object,
The present invention is based on a manual work area where manual work is performed and an automatic machine.
Each work is transported by a self-propelled transport member to an assembly line where there is an automatic work area where
Works while moving the transport members, and in the automatic work area
In the work transfer method in which the transfer member is stopped and the work is performed, and the transfer member is restarted with a waiting time after the end of the work in the automatic work area, the automatic work area is When the restart of the transfer member is delayed and the subsequent transfer member stays in the manual work area on the upstream side of the automatic work area, the waiting time related to the restart time of the subsequent transfer member from the automatic work area is reduced. Transport that is shorter than the normal value and delayed from the automatic
The stop time of the feeding member in the automatic work area is measured,
Of the transfer member to reduce the waiting time based on the stop time of
It is characterized in that the number is determined .

[0005]

Even if a trouble occurs in the automatic work area and a subsequent conveying member stays in the manual work area upstream of the automatic work area, the trouble is recovered and the work in the automatic work area is restarted. and during subsequent transport member is re-started from the automatic work <br/> area in a shorter time than the work after the end of the normal waiting time at the automatic work area, stop time of the conveying member in the end the automatic working area There is shorter than the normal time, the self-operating
The stagnation on the upstream side of the work area is eliminated. Incidentally, when the stop time of the conveying member in the automatic work center <br/> area is reduced, the self-operation
Since the work transfer pitch on the downstream side of the work area becomes narrower and the work is burdened by that much, the state of stagnation of the transfer member on the upstream side of the automatic work area is detected, and the waiting time is usually set in accordance with the state of stagnation. determining the timing of returning the value, the self-operation
It is conceivable to return the waiting time to the normal value when the stagnation on the upstream side of the work area is resolved,
Downtime is measured in the automatic work <br/> area of the conveying member which restart is delayed from the work area, be determined the number of conveying member to shorten the waiting time based on the stop time,
This eliminates the need for a special sensor for detecting the degree of stay of the transport member, which is advantageous in terms of cost.

When the assembly line is a mixed line for mixing and transporting different types of works, the line tact is generally set in accordance with the work of the maximum man-hour model in which the number of assembly steps is maximized. Regardless of the type of work, if the work is shortened by a constant width, the work of the work with many man-hours becomes severe. Therefore, it is desirable to change the reduction ratio of the waiting time to the normal value according to the type of work.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 denotes an automobile assembly line for assembling various parts on an automobile body, and a body W serving as a work in the line 1 is transferred to a self-propelled carrier 2 as shown in FIG. It was placed and transported. In the middle of the line 1,
An automatic work area 3 for performing work by an automatic machine such as a robot (not shown) is provided. In the manual work areas 4 and 5 on the upstream side and the downstream side, an operator moves on the carrier 2 for each process. while the required work on the vehicle body W on該台wheel 2, so that the applying operation by automatic machine of the vehicle body on該台vehicle 2 stops the conveyance carriage 2 in the automatic working zone 3 into place.

On the line side of the automatic work area 3, a controller 6, a sensor 7 for discriminating the model of the vehicle body from the model identifying means attached to the vehicle body or the transport vehicle 2,
Signal transmission means 8 for the sensor 7
The automatic machine is operated in accordance with the model determined in step (1), and after the work is completed, the carrier 2 is restarted by a signal from the signal transmitting means 8 as described later.

The speed and pitch of the carriage 2 are set in accordance with a line tact t ₀ determined based on a production plan. Normally, an automatic work area is set at a time interval from the manual work area 4 on the upstream side to t _0. The transporting trolleys 2 are sequentially loaded into 3. Here, the time t ₁ required for the working of the automatic work area 3 is shorter than t _0, the line side when the work end after t ₀ and latency t ₂ of the difference between t ₁ in the compartment area 3 has elapsed the controller 6
Transmits a start command signal to the transport vehicle 2 via the signal transmitting means 8 to restart the transport vehicle 2 so that the transport vehicle 2 is sequentially loaded into the downstream manual work area 5 at time intervals of t _0. I have to.

However, if a trouble such as a failure of the automatic machine occurs in the automatic work area 3 and the restart of the transport vehicle 2 is delayed, the subsequent transport vehicle is located upstream of the area 3 as shown in FIG. 2 stays, trouble recovers and automatic work area 3
Even if the operation in step (1) is resumed, if the transport trolley 2 is thrown from the area 3 to the manual operation area 5 on the downstream side at the time interval of t ₀ , the stagnation on the upstream side remains as it is, and the downstream side remains as it is. The work on the side is delayed, and the planned production volume cannot be achieved.

Therefore, when the work in the automatic work area 3 is resumed, the waiting time from the end of the work in the automatic work area 3 to the restart of the carrier 2 is set to the above-mentioned normal value t ₂ (= t ₀ −).
t ₁ ) is shortened from t ₂ by a value obtained by multiplying the predetermined shortening rate α, and the stop time of the transport vehicle 2 in the area 3 is shorter than t ₀ , so that the stagnation on the upstream side is eliminated. .

In this case, in the manual work area 5 on the downstream side of the automatic work area 3, as shown in FIG. 3 (b), the work is burdened because the pitch of the carrier 2 is narrowed, but the manual work area 4 on the upstream side is required. By temporarily turning the worker who has completed the work while staying in the manual work area 5 on the downstream side, the burden can be reduced.

By the way, the excess time of the stop time of the transport vehicle 2 in the automatic work area 3 at the time of occurrence of the trouble with respect to the normal stop time t ₀ (= t ₁ + t ₂ ) is represented by t.
Then, the number m of the transport vehicles 2 staying on the upstream side during that time is t / t ₀ . Further, the stop time of the transport vehicle 2 in the area after the recovery from the trouble is t ₁ + (1−α) t ₂ , which is shorter than the normal stop time t ₁ + t ₂ by αt ₂ ,
Assuming that the number of the transport vehicles 2 for shortening the stop time is n, αt
Saves only ₂ n times, becomes this t (= t ₀ m) that retained the upstream side is eliminated if. Therefore, the excess stop time t of the transport vehicle 2 in the automatic work area 3 is measured, and the number n of the subsequent transport vehicles 2 for which the waiting time is reduced is n = t.
/ Αt ₂ (however, the fractional part is rounded down), and if the waiting time is returned to t ₂ from the (n + 1) th unit, unnecessary work on the downstream side work can be avoided.

[0014] Incidentally, a sensor for detecting the upstream side of the residence state of the conveyance carriage 2 to the line side of the automatic work area 3, it may be to determine the timing of returning the waiting time t ₂ in accordance with the residence condition . However, if the number of units for which the waiting time is reduced is determined by the above-described method, a special sensor is not required, which is advantageous in cost.

Further, when a plurality of types of vehicle bodies W are mixed and conveyed to the assembly line 1, the waiting time of the conveyer truck 2 for conveying many man-hour models having a large number of assembling steps per process is reduced. If the waiting time of the bogie 2 is reduced to be equal to that of the bogie 2, the work of many man-hour models is overloaded. In this case,
The waiting time reduction rate α is set for each model so as to increase as the number of man-hours is reduced and stored in the controller 6, and the type of the vehicle body W on the carrier 2 existing in the automatic work area 3 is determined by the sensor 7. Then, the waiting time may be calculated by searching the shortening rate α corresponding to this model.

When the normal value t _{2 of the} waiting time is set to a different value for each model so that the transport pitch of the vehicle body W becomes longer as the number of man-hours becomes shorter and shorter as the number of man-hours becomes shorter at the normal time, It is not necessary to change the shortening rate α for each model.

[0017]

As is apparent from the above description, according to the present invention, even if the transport member stays upstream in the event of a trouble, the stay is gradually eliminated after the trouble is recovered.
A decrease in the number of production units due to a trouble can be avoided. Moreover,
The waiting time is returned to the normal value when the
In the manual work area downstream of the automatic work area
Work is not unnecessarily overloaded and stays in place
It eliminates the need for special sensors to detect
Can be cheap.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of an assembly line to which the method of the present invention is applied.

FIG. 2 is a side view showing an example of a conveying member.

FIG. 3A is a diagram showing a state when a trouble occurs;
(B) shows the state after recovery from the trouble

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Assembly line 2 Transport cart (transport member) 3 Automatic work area 6 Controller

Claims (2)

(57) [Claims] Claims: 1. A manual work area and an automatic machine for manual work
In conveying the work by the conveying member of each self-propelled to the assembly line and automatic work area to perform the work are mixed, people hand-ku,
In the area, work is performed while moving the transport member, and the automatic work area
In Complete stop conveying member, and, in the transfer method of the workpiece so as to restart the conveying member to exist a work end after waiting for the automatic working <br/> area, automatic
When the restart of the transfer member from the work area is delayed and the subsequent transfer member stays in the manual work area on the upstream side of the automatic work area, when the restart of the subsequent transfer member from the automatic work area is performed, Shorter waiting times and delayed restart from automatic work area
The stop time of the transport member in the automatic work area
Then, based on the stop time, the transfer for shortening the waiting time is performed.
A method for transporting a work in an assembly line, comprising determining the number of members . 2. An assembling line, which is a mixed line for mixing and conveying works of different types, wherein a reduction rate of the waiting time of the subsequent conveying member with respect to a normal value of the waiting time is determined by a model of the work conveyed by the subsequent conveying member. The method according to claim 1, wherein the method is changed according to the following conditions.