JPH0756997A - Work allocation system - Google Patents

Abstract

PURPOSE:To uniformalize burden on a worker and to reduce production loss at the early stage of production by allocating work to each worker by using standard working time, a worker level representing the working capacity of the worker, and the degree of difficulty of work. CONSTITUTION:The working time history storage part 16 of a skillfulness evaluation system 200 stores the actual working time of each worker measured by a work monitoring part 15 at every work sequentially, and a function approximation part 17 finds the change of the working time from a working time history by approximating to a work skill function. Furthermore, a parameter update part 18 updates by storing the worker level in each parameter of the work skill function in a worker information storage part 11, and the degree of difficulty of work and the standard working time in a work information storage part 12, respectively. The worker information storage part 11 of a work allocation system 100 stores the worker level with another information (age, the kind of experienced work. etc.) for the worker, and an allocation part 13 allocates the work by evaluating the combination of the capacity of the worker and the degree of difficulty of work, and allocated work is instructed to the worker by a work teaching part 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to work allocation in a manual production line for household appliances, etc., in consideration of the work load of the workers and the production efficiency.

[0002]

2. Description of the Related Art In a manual production line, a work manager is required to carry out the work to be carried out for each worker every time the model to be manufactured is changed, so that the working time of each worker is uniform and the takt time is kept constant. Allocate so that it becomes shorter. At this time, as described in Japanese Patent Application Laid-Open No. 3-28903, at the working time which is the basis thereof, the work manager analyzes the typical work operation by performing work analysis and the worker is sufficiently accustomed to the work. As a working time in such a state, a constant value was obtained and the working time of each work was determined based on this.

[0003]

However, since workers are beginners to skilled workers, their working ability is not constant.

Further, the current work ability of each worker is not grasped and managed. That is, the assignment is not made according to the work ability of each individual worker.For example, when an easy task is assigned to a skilled worker, there is play time in the task, while a difficult task is assigned to the beginner. If this happens, it will lead to overloading of workers and overtime of work. As a result, the work manager intends to equalize each work time as much as possible at the time of assignment, but in reality there is a difference in each work time, and the overall tact is constrained by the work with the highest worker load and is long. Therefore, there is a problem that the overall production efficiency is reduced.

Further, unlike the automatic assembly, the manual assembly does not always have a constant working time, and the working time exceeds the working time due to unaccustomed work, especially at the beginning of production, which leads to a production loss. Conventionally, the amount of products produced at one time per model (lot size) is large, and the initial production loss of the total amount can be ignored, or when the worker becomes accustomed to the work, the conveyor speed is increased. By shortening the tact a little, we were able to increase production and recover losses.

[0006] At present, the number of lots per model is reduced, the amount of the initial production loss occupies a large amount, and model switching occurs before recovery by shortening the tact time, which makes recovery of loss impossible. There is.

As a result, there are problems such as a discrepancy between the production plan and the actual production amount, and an increase in the load on the operator for significantly reducing the tact time for recovering the production amount.

An object of the present invention is to provide a work allocating system for allocating a work in a manual production line in consideration of work ability of a worker and work difficulty.

[0009]

In order to achieve the above object, in a work allocation system for allocating the above-mentioned work to each worker in a production line where production is performed by a plurality of works manually performed by a worker. , A worker information storage unit that stores a worker level that represents the work ability of each worker, a work information storage unit that stores the work difficulty level and standard work time that represent the difficulty level of each work, and the standard work time, , And a work allocating unit for allocating the work to each worker using the worker level and the work difficulty level.

[0010]

Since the work allocating section is configured as described above, the work allocating unit gives each worker the standard work time, the worker level indicating the work ability of the worker, and the work difficulty level. The above work can be assigned. for that reason,
It is possible to provide a line management system that allocates work in consideration of the work ability of each worker and the work difficulty level.

[0011]

EXAMPLES First, the outline of the examples will be described. In this embodiment, a worker level is set for each worker. Then, all of the combinations of worker level and work are evaluated, and the worker information storage unit that stores this together with other information about the worker (gender, date of birth, past experience work type, etc.). Therefore, by providing a work allocating section for making the work length as short as possible, it is possible to realize the allocation in consideration of the ability of the worker.

Further, the work time is not a fixed value but changes depending on time or the number of workpieces produced, and the time change is a work learning function described by α · exp (−β · n) + t.

A work monitor unit for measuring the actual work time of each worker and a work time history storage unit for sequentially storing the actual work time of each worker measured by the work monitor unit for each work are provided. , A function approximation unit that obtains a change in work time by approximating the work learning function from this work time history,
The above-mentioned worker level in each parameter of the work learning function is stored in the worker information section, the above-mentioned work difficulty level and the above-mentioned standard work time (minimum work time) are stored in the work information section, and each parameter is updated by a parameter updating section. The work allocation system will be used.

On the other hand, the work monitor unit calculates the work time of the worker from the worker position specifying unit for specifying the work position, the sensor array part in which a plurality of distance sensors are arranged in front of the worker, and the work position. It has a working time calculation unit that does

The worker information storage unit stores the sex of each worker, the date of birth, the past experience work, the number of times, the defect rate, the work start date and time, the finish date and time, the worker level indicating the work ability of the worker,
The worker information consisting of is stored. In addition, the work information storage unit stores work information including work operation of work, used parts, used jigs, and standard work time.

Here, the work familiarization function is defined as α · exp (−β · n) + t α: worker level β: work difficulty n: number of workpieces from the start of production t: minimum work time When allocating work to each worker, the allocator uses the work learning function based on the number of products, the worker level of each worker, the work difficulty of each work, and the minimum work time. Work time is calculated for all combinations of and work, and a combination that minimizes the total work time of each worker from the start of production to the end of production is assigned to each worker. The work monitor unit measures the actual work time for each worker. The work time history storage unit sequentially stores the actual work time of each worker measured by the work monitor unit for each work.

The function approximating unit obtains each parameter from the work time history so as to approximate the work learning function. The parameter updating unit stores the worker level, which is each parameter of the obtained work learning function, in the worker information unit, the work difficulty level,
The minimum work time is stored in the work information section and each of them is updated.

On the other hand, in the work monitor, a plurality of distance sensors are arranged in front of the worker in the sensor array unit, and the worker position specifying unit operates from the distance information from a plurality of distance sensors in the sensor array unit. The work position of the worker is automatically measured by specifying the position.

The worker position specifying unit periodically measures the work position, and the worker moving speed calculating unit obtains the worker speed from the worker position calculated periodically. Similarly, the work time calculation unit obtains the work time of the worker from the position of the worker.
Similarly, the worker movement distance calculation unit obtains the movement distance of the worker from the position of the worker. As described above, the worker moving speed, the working time, and the worker moving distance can be automatically obtained from the worker position.

An embodiment will be described in detail with reference to FIG. The target line here is a manual assembly line in which workers are arranged on a continuous conveyor to assemble works. The line management system according to the present invention is a work allocation system 1
00 and a proficiency level evaluation system 200. The work assignment system 100 includes a work vehicle law storage unit 11, a work law storage unit 12, an assignment unit (a reception unit that receives an instruction of the number of production units from the host computer 300) 13, and a work teaching unit 14. The proficiency level evaluation system 200 includes a parameter updating unit 18, a function approximation unit 17, a work time history storage unit 16, and a work monitor unit 15.

The worker information storage unit 11 stores the sex of each worker, the date of birth, and information about past experience work (type of work, number of times, defective rate, work start date and time and end date and time of the work (previous time). To consider that the worker level changes depending on the elapsed time from the work of this time to this work))
And the worker level including the worker level representing the work ability of the worker determined based on the information. The work information storage unit 12 stores work operations, used parts,
It stores work information including a jig to be used, a work difficulty level indicating the easiness of proficiency of a worker of the work, and a standard work time which is the minimum required time of the work when fully proficient.

When the work allocation section 13 is instructed to allocate a model, the entire work can be created in the shortest time.
A worker performs the work using the production quantity of the model from the upper-level production planning system (host computer 300), the worker level in the worker information storage unit 11, the work difficulty level and the standard work time in the work information storage unit 12. Assign to.

The function approximation section 17 is a working time history storage section 16
Each parameter is calculated so as to more closely approximate the work learning function. The parameter updating unit 18 stores the worker level, which is each parameter of the obtained work learning function, in the worker information unit 11.
The work difficulty level and the standard work time are stored in the work information section 12 and updated respectively.

Next, the allocation method in the allocation unit 13 will be described in detail.

First, the work time for each work type of each worker is obtained in advance by the work learning function of the worker α · exp (−β · n) + t. This function is shown in FIG. Here, the worker level indicates the ability of each worker to process the assigned work, and is actually the work time of the first one work of this model. Therefore, when the work ability is low, the value indicating the level is large, and when the work ability is high, the value is small. In addition, when the worker is the first and unknown worker level, the worker level is obtained by the following method.

First, the sex, date of birth, the number of works experienced in the past, the defect rate at that time, the work start date and time and the work end date and time in the worker information storage unit 11 which are the evaluation values of the workers in advance. Worker level values are set individually for such information. As an example, regarding the years of experience, I will keep it. Then, the worker level is obtained for each information of the worker, and the average value is set as the work level of the worker. Here, the level is clearly set and the level is calculated by the average value. However, other information may be defined by a membership function and fuzzy.

The work difficulty is the ease of performing the work,
Actually, it is a power coefficient of exponential function and means the degree of convergence of working time. A large value means that the work time for each number of works converges quickly, and the work is easy and easy to get used to.

The standard working time is the working time when the production of the model progresses and each worker is sufficiently proficient in the work, and is the working time used for the conventional allocation. When the work is performed for the first time, the work difficulty level and the standard work time are given constant values by the above-described method, similarly to the worker level.

The allocation takes the following steps.

1. For all combinations of the work of this model for a predetermined worker, the worker level, work difficulty, and standard work time are read from the worker information storage unit and the work information storage unit, and the work learning function is obtained.

2. Using the work learning function of each worker, the total work time of each worker from the start of production to the end of production of the model is calculated. An example of this result is shown in FIG.
The diagram is in matrix form of workers and work.

3. Based on the above results, the work will be assigned to the workers.

First, the shortest time of all combinations is searched. In this example, it is TnN. That is, the work N is assigned to the worker n. Next, work N and worker n
Search for the shortest time excluding, determine the work and worker, and assign. The above is repeated to obtain a combination of work and worker, that is, an allocation result.

The assigned work is instructed to the worker by the work teaching section 14. As an example of this teaching, a work of fixing a compressor, a tank, and a stopper to a work is taken as an example, and an example of a display screen display showing the contents of the work is shown in FIG. 4 and described. Four types of information are displayed on the screen in a window format. Sequentially explaining, information of the target work such as product code (41): manufacturing number 410, model number 411, work input date 412 and number 413 from the top is displayed. Parts list (4
2): Compressor 421 and tank 422 attached to it
Stoppers 423 for fixing the compressor 421 to the work 441.
The contents of parts such as 424 and 425 are shown. Difficulty in mounting parts (43): The difficulty level of the work is expressed in a level that is easy for the operator to understand. Here, it is assumed that the level A is difficult for the parts assembly work of the parts list numbers 1 and 2 in the previous term. Assembly direction and position: This is a diagrammatic representation of the attachment contents of the above-mentioned parts, and shows the posture of the parts and the attachment movement method.

Next, the work monitor section will be described. Since the work of the worker works on the work on the continuous conveyor, the work moves according to the work on the conveyor at the time of work, and when the work is completed, the work returns to the work start position for the next work. The above operation is repeated. That is, the time when the worker is moving in the same direction as the work moving direction means that the work is being performed, that is, the work time. Therefore, the working time is obtained by measuring the position of the worker and measuring the time from the start of movement to the stop in the movement direction of the work.

The operator position measuring mechanism will be described below. FIG. 5 shows the relationship between the line, the measuring mechanism, and the operator.
Reference numerals 41 to 44 denote distance sensors, which are ultrasonic sensors here, but may be other optical sensors. Reference numeral 45 is a worker position specifying unit that specifies the worker position based on the measured distance from each sensor. Although each of the distance sensors 41 to 44 and the worker position specifying unit 45 are connected by wire, this may be wireless. 46 is a worker to be measured. 47 is a conveyor. A work 48 is a work target. In front of the worker 46, there is a distance sensor array in which the distance sensors 41 to 44 are installed at regular intervals on the edge of the conveyor 47. The position of each distance sensor is known, such as by being measured in advance. In addition, the installation does not need to be at regular intervals on the line, and when the worker is sparse on the line, the measurement ranges of two or more distance sensors may overlap within the worker's work range depending on the situation. Any interval may be used.

Here, the position measurement for one worker will be described. The operator is assumed to be in the position shown in FIG.
Therefore, since the sensors 42 and 43 are within the distance measurement range, the sensors 42 and 43 allow the distance r2 as shown in FIG.
r3 is measured. This distance is transmitted to the work position specifying unit 45, and the work position specifying unit 45 specifies the position of the worker 46 by the following processing.

The respective positions p2 and p3 of the sensors 42 and 43 have been measured at the time of installing the sensors and are known. The intersection point p of the sensor positions p2 and p3 and the arcs of the respective distances r2 and r3 from them.
m is the position of the worker 46. Further, the same processing is performed for a plurality of workers to obtain the current positions of all the workers. The positions of all workers can be sequentially measured by periodically performing this measurement and processing. Next, the work time calculation unit 49 performs the following processing. Of the above-mentioned work positions, the worker's work start position is the most upstream of the conveyor (reverse direction of movement of the work) of each worker, and the most downstream of the conveyor (reverse direction of work movement) is the work end of the worker. It is a position, and the moving time during that time is the working time. Therefore, the difference between the work start time and the work end time is obtained as the work time.

Here, when the worker's work start position deviates downstream from the previous position, it means that the work is too time-consuming and there is little time to return. Therefore, it is possible to know the work load situation by monitoring the work start position of the worker.

The working time of each worker, which is periodically obtained as described above, is stored in the working time history storage unit 16 in the order of production. Using the work times stored in the work time history storage unit 16 arranged in the order of production, the learning function α · exp (−β · n) +
Find t.

First, the working time of the last stage of production is assumed to be the standard working time t, assuming that the work is sufficiently mastered. next,
The above t is subtracted from each work time for each machine, and the remaining values are calculated by the exponential function x · exp (-y
・ It approximates n). At this time, x and y are α and β. Here, the learning function value when n = 0 represents the work time when the worker starts work, and is the sum of the worker level α and the standard work time t. Finally, the parameter updating unit 18 stores the calculated worker level in the worker information storage unit 11 and the standard work time and the work difficulty level in the work information storage unit 12.

[0042]

According to the present invention, the work time is increased in consideration of the increase in the work time due to the unskilled work at the start of work, which has not been taken into consideration in the work allocation in the related art, so that the production loss can be reduced at the initial stage of production.

Further, since the work is performed in consideration of the ability of each worker, the load on each worker can be made uniform, overload and empty space can be reduced, and fatigue can be reduced and product reliability can be improved.

Further, since the work position of the worker can be constantly monitored by the work monitor unit of the present invention, the change in the work position is judged, and for example, if the work position is flowed downstream of the line, there is an overload or fatigue condition. On the contrary, it is effective for judging the work status of the worker, such as having a margin if it moves upstream.

[Brief description of drawings]

FIG. 1 is a block diagram of a line management system according to the present invention.

FIG. 2 is an explanatory diagram of each parameter of a function as an example of a work learning function according to the present invention.

FIG. 3 is an explanatory view showing an example of a work instruction screen of the present invention.

FIG. 4 is an explanatory diagram showing an example of a display of an operator monitor unit according to the present invention.

FIG. 5 is an explanatory view showing an example of a work instruction screen of the present invention.

FIG. 6 is an explanatory diagram of how to obtain the position of the worker.

[Explanation of symbols]

Claims (13)

[Claims] 1. In a work allocation system for allocating the above-mentioned work to each worker in a production line where production is performed by a plurality of works manually performed by the worker, a worker level representing the work ability of each worker. And a work information storage unit that stores a work difficulty level and a standard work time that represent the difficulty level of each work, the standard work time, the worker level, and the work difficulty level. A work allocating system having a work allocating unit for allocating the above-mentioned work to each worker by using the work allocating system. 2. The work allocation system according to claim 1, further comprising a receiving means for receiving an instruction of a production number, wherein the work allocation section uses the worker level, the work difficulty, the production number, and the standard work time. A work assignment system characterized in that a work learning function, which is a monotonically decreasing function of the number of products produced, is used to obtain the work time of each worker and to assign the work to each worker. 3. The work assignment system according to claim 2, wherein the work learning function is such that α is a worker level, β is a work difficulty level, n is a production quantity, and t is a standard work time.
A work allocation system characterized by being defined by exp (-β · n) + t. 4. The work assignment system according to claim 1, 2 or 3, wherein the work assignment unit assigns the work to each worker.
The work time is calculated for all the combinations of workers and works, and the work is assigned to each worker by finding the combination that minimizes the work time within the obtained work time. Work allocation system. 5. The work allocation system according to claim 2, 3 or 4, wherein a work time history storage unit for storing a history of the work time of each worker with respect to the number of produced products and the work learning function are used. A function approximating unit for approximating a change in working time from the working time history by a function of the working learning time to obtain respective constants of the worker level α, the work difficulty β, and the standard working time t. A characteristic work allocation system. 6. The work allocation system according to claim 5, further comprising a work monitor unit for measuring a work time of each worker, wherein the work time history storage unit stores the work time of each worker measured by the work monitor unit. A work allocation system characterized by storing work time. 7. The work allocating system according to claim 6, wherein the work monitor unit monitors a work whose start and work end can be recognized depending on the position of the worker, and the work monitor unit includes a plurality of works. A sensor array unit including a distance sensor, a worker position identifying unit that identifies a work position from distance information from a plurality of distance sensors in the sensor array unit, and a working time of the worker from the worker position A work allocation system, comprising: a work time calculation unit for calculating 8. The work allocation system according to claim 7, wherein the worker position specifying unit periodically specifies the worker position from distance information from a plurality of distance sensors in the sensor array unit. The work allocation system, wherein the work time calculation unit calculates the work time of the worker from the worker position calculated periodically. 9. The work assignment system according to claim 1, 2, 3, 4, 5, 6, 7 or 8, wherein the work assignment system has a work output section for outputting the assigned work details. . 10. The work of each worker in a proficiency level evaluation system for obtaining a work proficiency function for determining the work time of each worker in a production line in which a plurality of works are manually performed by the worker. A work time history storage unit that stores a history of time, α is a worker level that represents the work ability of each worker, β is a work difficulty level that represents the difficulty level of each work, n is the number of products produced, and t is the standard work time. Then, using the work learning function defined by α · exp (−β · n) + t, the change of the working time is approximated by the function of the working learning time from the working time history,
A function approximation unit for obtaining each constant of the worker level α, the work difficulty β, and the standard work time t, a worker information storage unit that stores the obtained worker level, and the obtained work difficulty And a work information storage unit that stores the standard work time. 11. The proficiency evaluation system according to claim 10, further comprising a work monitor unit for measuring a work time of each worker, wherein the work time history storage unit is each worker measured by the work monitor unit. A proficiency level evaluation system characterized by memorizing the work time of each. 12. The proficiency level evaluation system according to claim 10, wherein the work monitor unit monitors a work whose start and end are visible depending on the position of the worker, and the work monitor unit is composed of a plurality of work monitors. Sensor array part consisting of the distance sensors, a worker position specifying part for specifying a work position from distance information from a plurality of distance sensors in the sensor line part, and a work time of the worker is calculated from the worker position. A proficiency level evaluation system comprising: 13. The proficiency level evaluation system according to claim 12, wherein the worker position specifying unit periodically specifies the worker position from distance information from a plurality of distance sensors in the sensor array unit. The proficiency evaluation system is characterized in that the work time calculation unit calculates the work time of the worker from the worker position calculated periodically.