JPH086804A - Load allocating method - Google Patents

Abstract

PURPOSE:To perform proper allocation even if loads have variance by setting capability frames in stages, classifying the loads into load groups corresponding to the capability frames, one to one, according to the sizes of the loads, and allocating the load groups to the capability frames in decreasing order. CONSTITUTION:Two intermediate-load capability frames 11 are set in a large- load capability frame 10 and two small-load capability frames 12 are further set in each intermediate-load capability frame 11. Thus, the loads are classified into the load groups corresponding to the phased capability frames 10, one to one, and the largest load group is allocated to the load capability frame 10 having the largest capacity. The 2nd large load group is allocated to a load capability frame 11 with 2nd capacity and the smallest load group is allocated to a load capability frame 12 with the smallest capacity lastly, so that all the loads are allocated. At the time of the allocation, the respective capability load frames 10-12 can have allocation priority order, capability priority order, allocation conditions of process intervals, etc., optionally set.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a load allocating method capable of appropriately allocating a load having a variation in man-hours to a machine in a process control of a multi-item production using a plurality of machines in a factory.

[0002]

2. Description of the Related Art In factories, in order to plan and operate production activities reasonably and efficiently, process control is performed so that products of a certain quality and quantity are completed by a predetermined date. As part of this process control, the machines necessary for producing the products are rationally assigned and the process is organized. Generally, in the case of mass production, there is a sufficient amount of work for each machine with only one type of product, so each machine is arranged in a process order convenient for progress control and transportation, and a line shop type process organization dedicated to that product It is carried out.

On the other hand, in a variety of small-quantity production, since only one kind of product does not have the necessary and sufficient amount of work for each machine, the machines of the necessary type and number of machines common to the entire product group are provided. Various job-shop-type process organizations that are arranged according to the functions that are convenient for starting control have been developed, and a variety of computer program programs of such process organizations have been developed.

The general approach in that case is to use the theory of ordering to find a plan that minimizes the total elapsed time to complete all work. In this method, a general solution has not been found, so if it is tried in a brute force manner, a combination explosion may occur. In reality, it is often the case that each job is within a certain period of time, so jobs (hereinafter referred to as loads) are assigned as follows so that a combination explosion does not occur.

FIG. 5 is a diagram for explaining the basic concept of a conventional load allocation method.
In the figure, A, B, and C indicate machines that allocate loads, and the horizontal axis represents time. These machines A, B, C
Consider the case of manufacturing three types of products using. The processes for completing each product are load 1, load 2, and load 3. For example, load 1 includes steps 1a, 1b, 1c
The load 2 is the process 2a, 2b, 2
c and the load 3 are processes with man-hours 3 such as processes 3a, 3b, and 3c. Where lowercase letters a, b, c
Indicates that the steps are performed using the machines A, B, and C, respectively. When allocating such a load, a procedure of avoiding the load already allocated so that the processes of the same product do not overlap with each other and allocating the load to a target machine or a vacant time zone of the personnel is taken.

In such load allocation, the example of FIG. 5 is a very simplified example in which the man-hours of the loads 1 to 3 are three. However, in general, there are some variations in the man-hours and sizes of the loads to be allocated, and the vacant time is short and rather scattered. Even then,
The plan should have as short a lead time as possible from the product completion date. Therefore, it is necessary to create a vacant area in one place by moving the vacant time or move the time zone of the already allocated load (hereinafter referred to as backtrack).

[0007]

FIG. 6 shows machines A, B, and
An example in which loads of five types of processes are assigned to C is shown. In this figure, the numbers 1 to 5 represent the loads of the same product. Referring to the allocation to the machine B in FIG. 6 as well, in order to shorten the lead time, it is preferable to allocate the load 2 as close to the right side of the drawing as possible. However, since the load 2 assigned to the machine C overlaps, the assignment is as shown in the figure. Further, since the load of 4 assigned to the machine B is assigned so as not to overlap with the load 4 assigned to the machine A, a free time is left.
Further, since the load 3 of the machine C overlaps the load 3 of the machine B, it is necessary to backtrack and move as shown in the figure in this case. In this way, when there are many types of load and there are variations in the size of the load, and the load is divided into multiple processes, it becomes complicated to allocate properly, especially backtrack processing becomes difficult. However, there is a drawback that the allocation takes time. Therefore, an object of the present invention is to provide a load allocation method that solves the problems of the prior art and enables appropriate load allocation even when the size of the load varies.

[0008]

In order to achieve the above-mentioned object, the present invention sets a capacity frame to which a load is allocated in a plurality of stages according to the size of the capacity, and allocates the load according to the size. Then, the load groups corresponding to each stage of the above capacity frame are categorized into one-to-one correspondence, the load group of the largest size is first assigned to the capacity frame of the maximum capacity, and the load groups are sequentially arranged in ascending order to the capacity frame of the corresponding capacity. It is characterized by allocation.

FIG. 1 shows a capability frame set in three stages, for example. Reference numeral 10 is a large-load capacity frame. Two medium-load capacity frames 11 are set in the large-load capacity frame, and two small-load capacity frames 12 are set in the medium-load capacity frame 11. Assuming that the capacity of the small-load capacity frame 12 is T1, the medium-load capacity frame 11 has two small-load capacity frames 12.
Therefore, the capacity T2 of the medium capacity capacity frame 11 is 2T1 and the capacity T3 of the large capacity capacity frame 10 is 4T1.

Here, the allocatable condition of the large load capacity frame 10 is that the free space E1> the total sum W1 of the magnitudes of the loads. The free capacity E1 of the large load capacity frame 10 after the allocation is the free capacity E1 '= the free capacity E1−the total W of the allocated loads.
Becomes 1.

Next, the allocatable condition of the medium load capacity frame 11 is that the available capacity E2> the sum of the load magnitudes W2, and that the medium load capacity frame 11 contains the large load capacity frame 10. That is, the load can be assigned, that is, the free space E1> the total sum W2 of the magnitudes of the loads is satisfied. After the load is allocated, the free capacity E2 '= E2-W2 of the free capacity E2' = E2-W2 of the medium load capacity frame 11 and the large load capacity frame 10, respectively, the free capacity E1 '= E1- (W1 + W2 ) Is.

[0012] In the same way, the assignable condition of the small load capacity frame 12 is that the empty capacity E3> the sum W3 of the load magnitudes and the small load capacity frame 12 is included. 11. The load of the large load capacity frame 10 can be assigned, that is, all the conditions of free capacity E2> sum W3 of load magnitude> free capacity E1> sum W3 of load magnitude are satisfied. After the load is allocated, the free capacity E3, E2 '', E1 '''of each of the small load capacity frame 12, the medium load capacity frame 11 and the large load capacity frame 10 is the free capacity E3 = E3 -W3 free capacity. E2 ″ = E2− (W2 + W3) Free space E1 ′ ″ = E1− (W1 + W2 + W3). In this way, it is possible to confirm the presence or absence of the free capacity without defining the allocation position within each capacity frame.

In this way, since the already allocated load does not define the position in each capacity frame, the empty area in the frame is not dispersed as a thin fragmentary empty area, and there is an empty area. It becomes clear that the load is allocated, and if there is no space, it cannot be allocated.

[0014]

According to the present invention, the loads are classified into load groups in one-to-one correspondence with the graded capacity frames, and the largest load group is assigned to the load capacity frame having the largest capacity. Next, the second largest load group is allocated to the load capacity frame of the second capacity, and so on, and so on. Similarly, the third and fourth allocations are continued, and finally, the smallest load group is allocated to the smallest capacity. When assigned to the load capacity frame, all loads are assigned. At the time of the allocation, in each load capacity frame, allocation priority order, capacity adjustment priority order, process interval allocation conditions, etc. can be arbitrarily set. In this way, by optimizing the number of stages of the processing capacity frame according to the degree of load variation, it is possible to appropriately assign loads of various variations.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the load allocation method according to the present invention will be described below with reference to the accompanying drawings. In this embodiment, the number of stages of the machining capacity frame is set to three, and the machining process of a product using three machines will be described with reference to a specific example. When assigning the load to each machine, a stepwise machining capacity frame is set in advance. In this embodiment, the load capacity is set to three levels, that is, the heavy load frame, the medium load frame, and the small load frame. The heavy load frame is assigned a load capacity of up to 80 hours, and the medium load frame is assigned 40 hours and a small load capacity. The load is assigned a capacity of 20 hours. On the other hand, regarding the jobs assigned to the machines A, B, and C, the process 1 is shown in Table 1.
Consider four types of processes, from 1 to 4. In this case, for example, if step 1 is explained, the machine A is used 1
0 hour required load and 50 hours using machine B
It consists of two types of loads, that is, 40 hours, and the loads required for using the machine C, that is, 8 hours and 5 hours. Regarding step 3, the load using the machine A is 30 hours, the load of the machine B is 3 hours, which is a small load, and the load of the machine C is
40 hours, 10 hours, 5 hours compared to process 1, machine C
Is a fairly heavy process to use.

As described above, the load required to complete the product through each process requires the required time listed in Table 1, and the load varies among the processes. .

[0017]

[Table 1] Next, the respective loads having such variations are made to correspond one-to-one to the previously set processing capacity frames, and are classified into load groups according to their sizes. The results of this classification are shown in Table 2.
Shown in

[0018]

[Table 2] Here, each load is a heavy load frame with a maximum capacity of 80 hours,
Frames for medium load with maximum capacity of 40 hours and frames for small load with maximum capacity of 20 hours are classified according to the categories. In the case of this embodiment, the largest load group is designated as JOB2, which represents the load group to be assigned to the heavy load frame, and the next largest load group is JO.
The load group classified as B4 is set as the medium load frame, JOB1,
The small load groups classified as JOB3 and JOB5 are assigned to the small load frame.

Next, FIG. 2 shows the result of allocating the load group of JOB2 to the heavy load frame, and FIG. 3 shows the result of allocating the load group of JOB4. Finally, as shown in FIG. 4, JOB1, JOB3, and J are attached to the small-load frames, respectively.
Assign OB5.

When sequentially allocating in ascending order from such a large load group, it is determined whether or not there is a free area in each machining capacity frame in accordance with the above-described calculation procedure,
Allocate. Within the same processing capacity frame, the load allocation position is not specified, so if there is an empty area in each processing capacity frame, the load will be allocated reliably.

[0021]

As is apparent from the above description, according to the present invention, capacity frames are set in stages, and the capacity frames are classified into load groups corresponding to the capacity frames one by one. Since the load groups are assigned to the capacity frames in descending order, appropriate assignment can be performed even if there are variations in the load magnitude.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an example of a stepwise capacity frame in a load allocation method according to the present invention.

FIG. 2 is an explanatory diagram of an example in which the largest load group is assigned to the largest capacity frame.

FIG. 3 is an explanatory diagram of an example in which the next largest load group is assigned to the next largest capacity frame.

FIG. 4 is an explanatory diagram of an example in which the smallest load group is assigned to the smallest capacity frame.

FIG. 5 is a conceptual explanatory view of a conventional load allocation method.

FIG. 6 is an explanatory diagram showing an example in which loads are specifically assigned by a conventional load assignment method.

[Explanation of symbols]

 10 Large load capacity frame 11 Medium load capacity frame 12 Small load capacity frame

Claims (1)

[Claims] 1. A capacity frame to which a load is assigned is set in a plurality of stages according to the size of the capacity, and the load to be assigned is classified into a load group corresponding one-to-one to each stage of the capacity frame according to the size. Then, the load allocation method is characterized by first allocating the largest load group to the maximum capacity capacity frame, and then sequentially allocating the load groups to the corresponding capacity capacity frame in ascending order.