TWI824458B - Maintenance management device, maintenance management method, and maintenance management program - Google Patents

Abstract

The present disclosure proposes a maintenance management device, a maintenance management method, and a maintenance management program that can reduce losses in a manufacturing process. The maintenance management device 50 includes: a control portion 51 that determines maintenance information of a processing device 10 for manufacturing processed products; and an output portion 53 that outputs the maintenance information determined by the control portion 51. The control portion 51 determines the maintenance information based on the maintenance cost for the maintenance of the processing device 10, and the failure cost due to the processing device 10. The failure cost includes the opportunity loss generated due to the failure and shutdown of the processing device 10.

Description

Maintenance management device, maintenance management method and maintenance management program

This disclosure relates to maintenance devices, maintenance methods and maintenance procedures.

In the past, there was a method of updating the scheduled maintenance period of the equipment using a loss function defined by the equipment. In the method described in Patent Document 1, a loss function is determined that takes into account the loss when a machine breaks down. Also, the scheduled maintenance period is changed to reduce losses based on the loss function.

Furthermore, Patent Document 2 describes how to calculate the amount of damage when a failure occurs and the probability of missing failure symptoms by location, and estimate the risk of each location based on the failure rate, the amount of damage when a failure occurs, and the probability of missing failure symptoms. , to evaluate maintenance methods.

[Prior patent documents]

[Patent Document]

Patent Document 1: Japanese Patent Application Publication No. 2004-145496

Patent Document 2: Japanese Patent Application Publication No. 2004-152017

The processing equipment used in the manufacturing steps of the product is maintained to minimize manufacturing costs. losses during the manufacturing step. In order to further reduce losses in the manufacturing steps, it is necessary to properly manage the maintenance of processing equipment.

Therefore, the purpose of this disclosure is to provide a maintenance management device, a maintenance management method and a maintenance management program that can reasonably reduce losses in the manufacturing process.

An implementation form of the present disclosure to solve the above problems is as follows:

[1] A maintenance management device, including: a control unit that determines maintenance information of a processing device that manufactures processed products; and an output unit that outputs the maintenance information determined by the control unit, wherein the control unit is based on the maintenance operation requirements of the processing device. The maintenance cost incurred and the failure cost caused by the processing device determine the maintenance information. The failure cost includes the opportunity loss caused by the failure of the processing device.

[2] In the maintenance management device of [1], the control unit generates a loss function using the post-maintenance operation time corresponding to the operation time of the processing device after the maintenance operation of the processing device as a parameter, and the loss function expresses the relationship between The control unit determines the sum of the first term, which is proportional to the product of the reciprocal of the post-maintenance operating time and the maintenance cost, and the second term, which is proportional to the product of the post-maintenance operating time and the failure cost, based on the loss function. This maintenance information.

[3] In the maintenance management device of [2], the control unit determines the post-maintenance operation time when the value of the loss function reaches a minimum value or when it is within a range of a predetermined value relative to the minimum value, as The maintenance information is calculated.

[4] In the maintenance management device of [2] or [3], the control unit determines that the failure cost of the second term of the loss function is a value obtained by multiplying the opportunity loss by a coefficient based on the operating status of the processing device. In the form of , the loss function is generated.

[5] In the maintenance management device according to any one of [2] to [4], the control unit is configured such that the failure cost of the second term of the loss function is multiplied by a coefficient based on the characteristic factor of the processing device, generate this loss function.

[6] A maintenance management method, including: the maintenance management device determines the processing equipment for manufacturing the processed product. The steps for setting the maintenance information are determined based on the maintenance cost of the maintenance operation of the processing device and the failure cost caused by the processing device; and the steps for the maintenance management device to output the determined maintenance information, wherein the failure The cost includes the opportunity lost due to the failure of the processing equipment to stop.

[7] A maintenance management program that causes a processor to execute steps, including the step of determining maintenance information for a processing device that manufactures processed products based on the maintenance cost of the maintenance operation of the processing device and the reasons for the processing device. It is determined based on the failure cost; and the step of outputting the determined maintenance information, wherein the failure cost includes the opportunity loss caused by the failure of the processing device.

According to an implementation form of the present disclosure, losses in the manufacturing steps can be reduced.

1: Maintenance management system

10: Processing device

11: Part 1 (Guide roller bearing)

12: line

14:Roller

16: Line group

18: Workpiece holding mechanism

20:Nozzle

32: Guide roller

33: Swing arm

34: Swing roller

35:Touch wheel

36: Drive motor

38,38A,38B: line reel

40:Abrasive storage tank

42:Abrasive cooler

50: Maintenance management system

51:Control Department

52: Ministry of Communications

53:Output Department

54:Input part

60:Run the server

70: Non-running server (maintenance DB)

W: workpiece (block)

X:Roller axis direction

FIG. 1 is a block diagram showing an architecture example of a maintenance management system according to an implementation type.

FIG. 2 is a schematic diagram showing a frame example of a wire saw device as a processing device.

3 is a plan view and a side view showing an example of the frame of the guide wheel of the wire saw device.

FIG. 4 is an example of a graph showing a loss function generated by the maintenance management device according to the embodiment.

FIG. 5 is an example of a graph illustrating a loss function of maintenance costs when the actual operation rate is lower than the assumed operation rate.

FIG. 6 is a flowchart showing an example of steps of a maintenance management method according to an embodiment.

FIG. 7 is an example of a graph showing a loss function when the mean time between failures of the processing equipment is taken into consideration.

[Outline of maintenance management system 1 of one embodiment]

A maintenance management system 1 (see FIG. 1 ) or a maintenance management device 50 (see FIG. 1 ) according to an embodiment of the present disclosure. (See Figure 5) The processing device 10 (see Figure 1 or Figure 2) installed in a factory or the like that manufactures products is managed. The processing device 10 processes the received member in at least part of the steps of manufacturing the product and sends it out as a processed product.

The processing device 10 may stop during processing. In this case, the processed products that were previously processed are sent out as defective products. Furthermore, even if the processing device 10 is not stopped, the processed product may be sent out as a defective product. Failure of the processing device 10 and delivery of defective products will cause losses in the processing device 10 in a manner that is easily apparent. Faults that cause losses in the processing device 10 in an easily visible manner are called manifest faults. Manifest faults are also referred to as faults detected in the processing device 10 .

On the other hand, even if the processed product sent out from the processing device 10 is judged to be a good product, there may be cases where the final product obtained after the processed product is further processed in subsequent steps is a defective product. The defective final product may be caused by the quality of the processed product sent out from the processing device 10 . The production of defective products in the final product will reduce the yield rate. That is, the processing apparatus 10 may cause a decrease in the yield of the final product. Specifically, if the same part is continuously used in the processing apparatus 10, the part will deteriorate. Deterioration of parts may cause performance degradation of the parts or degradation of the performance of the processing device 10 . Furthermore, when the processing device 10 is continuously used, at least a part of the processing device 10 deteriorates. Deterioration of the processing device 10 causes a decrease in the performance of the processing device 10 . If the processing device 10 continues to process parts or the performance of the processing device 10 is degraded, the quality of the processed product will be degraded. The decline in the quality of processed products will cause a decline in the yield of the final product. The decrease in yield due to the yield of processed products will cause losses in the processing device 10 in a form that is difficult to show. Faults that cause losses in the processing device 10 in a form that is difficult to show are also called hidden faults. Hidden faults are also referred to as faults that are not discovered in the processing device 10 and are only discovered in subsequent steps after the object is processed. In addition, a malfunction may cause the processing device 10 to stop. Opportunities are lost due to the stoppage of the processing device 10 . The opportunity loss will depend on the operating rate of the processing device 10 .

The maintenance management system 1 or the maintenance management device 50 according to an embodiment of the present disclosure can manage the maintenance work of the processing device 10 by considering the opportunity loss included in the apparent failure. The maintenance operations of the processing device 10 may include replacement, cleaning, or oiling of parts of the processing device 10 . The maintenance management system 1 or the maintenance management device 50 may manage the maintenance work of the processing device 10 by determining the maintenance interval or maintenance frequency of the processing device 10 , or may determine the maintenance time point of the processing device 10 . In other words, the maintenance work of the processing device 10 is managed by taking into account not only the cost of repairing the failure of the processing device 10 but also the opportunity loss caused by the stoppage of the processing device 10 . Thereby, the loss caused by the processing device 10 can be reduced.

Here, the processing device 10 is assumed to include the first component 11 (see FIG. 1 ). An apparent malfunction or hidden malfunction of the processing device 10 may occur due to deterioration such as wear or deformation of the first component 11 . The maintenance management system 1 or the maintenance management device 50 of this embodiment can manage the maintenance work of the processing device 10 and determine the replacement interval of the first component 11 . The replacement interval of the first component 11 corresponds to the time required to operate the processing device 10 after the first component 11 in the processing device 10 is replaced with a new product, and then until the first component 11 is replaced with a new product. The maintenance management system 1 or the maintenance management device 50 is not limited to determining the replacement interval of parts, but may also determine the replacement frequency of parts or the replacement time of parts to manage the maintenance work of the processing device 10 .

In addition, a plurality of processing apparatuses 10 may be installed in a manufacturing factory. If the amount of loss reduction per processing device 10 is slightly increased, the increase in the amount of loss reduction for the entire manufacturing plant cannot be ignored.

Hereinafter, a structural example of the maintenance management system 1 and the maintenance management device 50 according to an embodiment will be described.

[System architecture example]

As shown in FIG. 1 , a maintenance management system 1 according to an embodiment includes a maintenance management device 50 , an operating server 60 , and a non-operating server 70 .

The maintenance management device 50 includes a control unit 51 , a communication unit 52 , an output unit 53 , and an input unit 54 . The control unit 51 provides control and processing capabilities for executing various functions of the maintenance management device 50 . Control Department 51 generates information on the maintenance work of the processing device 10 as will be described later. Information regarding the maintenance work of the processing device 10 is also called maintenance information. The maintenance information may also include maintenance intervals, maintenance frequencies, or maintenance time points of the processing device 10 . The maintenance information may include information that specifies the parts of the processing apparatus 10 to be maintained.

The control unit 51 may include at least one processor. The processor can execute programs that implement various functions of the control unit 51 . The processor can also be implemented as a single integrated circuit. Integrated circuits are also called IC (Integrated Circuit). The processor may also be implemented as a plurality of communicatively connected integrated circuits or discrete circuits. The processor may be implemented based on various other known technologies.

The control unit 51 may include a storage unit. The storage unit may include an electromagnetic storage medium such as a magnetic disk, or may include a memory such as a semiconductor memory or a magnetic memory. The storage may also include non-transitory computer-readable media. The storage unit stores various information, programs executed by the control unit 51, and the like. The storage unit may also function as a working memory of the control unit 51 . At least part of the storage unit may be configured separately from the control unit 51 .

The communication unit 52 can be communicatively connected to other devices such as the operating server 60 or the non-operating server 70 . The communication unit 52 may also be connected to the processing device 10 for communication. The communication unit 52 can also be communicatively connected with other devices through the network. The communication unit 52 may also be connected to other devices via wired or wireless communication. The communication unit 52 may also be equipped with a communication module to connect to the network or other devices. The communication module can have a communication interface such as LAN (Local Area Network). The communication module may also have a communication interface for contactless communication such as infrared communication or NFC (Near Field communication) communication. The communication module can also realize communication through various communication methods such as 4G or LTE (Long Term Evolution). The communication method performed by the communication unit 52 is not limited to the above-mentioned example, and may also include various other methods.

The output unit 53 outputs the information acquired from the control unit 51 . The output unit 53 may output information to notify the operator or maintenance person of the processing device 10 . The output unit 53 may include a display device. The display device may include, for example, a liquid crystal display, an organic EL (Electroluminescence) display, or an inorganic EL display, etc., but it is not limited to this and may include other devices. The output unit 53 can display the information obtained from the control unit 51 on the display device in the form of text, images, etc., and notify the surroundings of the information.

The output unit 53 may include a light source such as an LED (Light Emission Diode) or a halogen lamp. The output unit 53 can turn on and off the light source based on the information obtained from the control unit 51, thereby notifying the information to surrounding operators, maintenance personnel, and the like. The output unit 53 may include a piezoelectric buzzer, an electromagnetic buzzer, or a speaker that emits a predetermined sound. The output unit 53 buzzes a buzzer, makes a speaker sound, etc. based on the information acquired from the control unit 51, thereby notifying surrounding operators, maintenance personnel, etc. of the information.

The output unit 53 may output information to the processing device 10 . The output part 53 may also be equipped with a communication module so that it can be connected to the processing device 10 for communication.

The output unit 54 is provided with an input device for accepting inputs operated by an operator, a maintenance person in charge, etc. who manage the maintenance management device 50 . The input device may include, for example, a keyboard or physical keys, or may include a touch panel, a touch sensor, or a pointing device such as a mouse. When the input device is a touch panel or a touch sensor, it may be configured integrally with the display of the output unit 53 . The output device may include, for example, a microphone that accepts audio input. The input unit 54 is not limited to these examples as an input device. Various other devices may also be included.

The operation server 60 stores the operation data of the entire factory. The operating data may also include data on the operating status of the processing device 10 or the number of productions, quality data on the processed products or final products sent out from the processing device 10, or yield data. The data stored in the operation server 60 may also include data measured by a measuring device, for example. The operation server 60 obtains the operation data from the processing device 10 . The operation server 60 outputs operation data to the maintenance management device 50 . The operation server 60 may also output the stored data as requested by the maintenance management device 50 . The execution server 60 may also include at least one processor. The processor may have the same or similar configuration as the processor included in the control unit 51 .

The non-operation server 70 stores data related to the processing device 10 such as labor costs and parts costs. material. Non-running servers 70 may also constitute databases. The non-running server 70 outputs the stored data to the maintenance management device 50 . The non-running server 70 may also output the stored data due to the request of the maintenance management device 50 . The non-running server 70 may include at least 1 processor. The processor may have the same or similar configuration as the processor included in the control unit 51 . The non-operational server 70 may also include a storage unit for storing data. The storage unit may have the same or similar structure as the storage unit included in the control unit 51 . The non-operation server 70 has a database that stores various information including equipment parts of the processing device 10, parts costs thereof, and labor costs. The database of the non-running server 70 is also called a maintenance database (maintenance DB).

[Specific example of processing device 10: wire saw device]

In this embodiment, the processing device 10 is assumed to be a wire saw device. As shown in FIG. 2 , the processing device 10 as a wire saw device is provided with a wire group 16 that stretches the wires 12 so that they can move back and forth between a plurality of rollers 14 . The processing device 10 includes a workpiece holding mechanism 18 that holds the workpiece W and moves the workpiece W toward the wire group 16 in the pressing direction. The processing device 10 is provided with a pair of nozzles 20 that supply abrasive to the area where the workpiece W of the line group 16 is pushed. The processing device 10 cuts the workpiece W using the wire group 16 . The workpiece W is a block body of silicon (single crystal silicon rod cut into blocks). The processing device 10 delivers silicon or other sliced wafers obtained by cutting the workpiece W as a processed product. In the following, if the processing device 10 is a wire saw device, it is assumed that the processed product is a sliced wafer.

The wire 12 is wound around a set of wire spools 38A and 38B. The thread 12 is drawn from the thread reel 38A on one side to the thread reel 38B on the other side via the guide roller 32 and the roller 14 and the like.

The line reels 38A and 38B are each rotated by the drive motor 36 . The drive motor 36 drives and rotates the line spools 38A and 38B, whereby the line 12 can be extended from the line spool 38A on one side and moved to the line spool 38B on the other side through the guide roller 32 and the roller 14 and the like. The wire 12 moves via a tension applying device including a swing arm 33, a swing roller 34, and the like. As the wire 12 moves through the tension applying device, tension is applied to the wire 12 . Line 12 moves via touch roller 35 . When the touch roller 35 is extended from the line reels 38A and 38B or wound around the line reels 38A and 38B, it moves following the position of the moving line 12 .

The wire 12 is spirally wound around a plurality of rollers 14 multiple times. The spirally wound wires 12 form a wire group 16 arranged in a direction perpendicular to the roller axis direction X between the rollers 14 . The roller 14 has a structure in which polyurethane is pressed into the periphery of a steel cylinder and grooves are cut at certain intervals on the surface. The wires 12 are embedded in grooves cut on the surface of the roller 14, whereby the wire group 16 can move stably.

The direction of movement of the wire 12 is controlled by the direction of rotation of the drive motor 36 . The wire 12 can also be controlled to move in one direction, or back and forth as needed. The amount of tension applied to the wire 12 can be set appropriately. The moving speed of the wire 12 can be set appropriately.

The abrasive supplied to the wire group 16 from the nozzle 20 is stored in the abrasive storage tank 40, and is sent from the abrasive storage tank 40 to the nozzle 20 through the abrasive cooler 42 that regulates the temperature of the abrasive.

As shown in FIG. 3 , the guide roller 32 has the first component 11 . The first component 11 is also simply called a component. In this embodiment, the first component 11 is a guide roller bearing. As will be described later, the first component 11 is not limited to the guide roller bearing and may be other components. The guide roller 32 is embedded around the shaft of the guide roller bearing. The guide roller bearing is rotatably mounted to the processing device 10 . The guide roller embedded in the guide roller bearing is mounted rotatably relative to the processing device 10 and can smoothly move the wire 12 while limiting the position of the wire 12 .

The sliced wafers sent out as processed products from the wire saw device are further processed in steps such as polishing, and the wafers are shipped as final products.

[Examples of maintenance management methods]

Hereinafter, a method in which the maintenance management device 50 manages the maintenance work of the processing device 10 will be described. The replacement interval of the first component 11 (guide roller bearing) is determined by the method explained below.

The maintenance management device 50 determines the replacement interval of the first part 11 based on the management cost required for replacement and the failure cost due to failure of the processing device 10 . The longer the replacement interval of the first part 11 is, the management cost will be reduced, but the failure cost will be increased. On the contrary, as the replacement interval of the first component 11 is shortened, although the failure cost will be reduced, the management cost will be increased. The operating costs of the processing device 10 can vary depending on The smaller the sum of management cost and failure cost, the lower it will be. Therefore, the maintenance management device 50 determines the replacement interval of the first component 11 in order to reduce the sum of the management cost and the failure cost. The maintenance management device 50 may determine the replacement interval of the first component 11 so that the sum of the management cost and the failure cost is minimized.

The maintenance management device 50 can determine the replacement interval of the first component 11 by the method described below, thereby reducing the sum of the management cost and the failure cost.

<Management costs>

The management cost is the cost required to replace the first part 11 (guide roller bearing). The fees required to exchange are also known as interchange fees. Exchange cost includes parts cost for guide roller bearing. The exchange fee also includes the labor cost of the exchange operation. The exchange cost further includes the opportunity loss caused by stopping the processing device 10 during the exchange operation. The opportunity loss corresponds to the value of the sliced wafers sent out if the processing apparatus 10 continues to operate during the replacement operation.

<Failure Cost>

Failure costs include losses caused by apparent failures and losses caused by hidden failures.

<<Loss caused by display failure>>

A manifest fault is a fault that occurs with a given probability of occurrence. The apparent failure may occur due to the first part 11. This is because the probability of occurrence of apparent failure of the first part 11 can be determined based on the state of the first part 11 . The longer the operating time of the processing device 10 after the maintenance of the first part 11 is, the higher the probability of occurrence of a manifest failure of the first part. The operation time of the processing device 10 after the maintenance of the first component 11 is also called the post-maintenance operation time. This is because the occurrence probability of apparent failure of the first part 11 is assumed to be proportional to the operation time after maintenance.

The amount of loss during the period when no apparent failure occurs is zero. However, a certain amount of damage will be incurred at the time when the apparent failure occurs. The amount of loss caused by one apparent failure is fixed regardless of the time when the apparent failure occurs. Because manifest failures occur randomly, the expected value of the loss caused by manifest failures is calculated. The expected value of the loss caused by a manifest failure is expressed as the product of the amount of loss caused by one manifest failure and the occurrence probability of the manifest failure. The occurrence probability of apparent failure and the operation after maintenance In the case that the operation time is proportional, the expected value of the loss caused by the apparent failure will increase with the longer the operation time after maintenance.

Here, the loss caused by an apparent failure is represented by the expected value of the amount of loss caused by an apparent failure. In order to reduce losses caused by apparent failures, it is effective to shorten the running time after maintenance.

<<Loss caused by hidden fault>>

Hidden faults are different from manifest faults and are not apparent faults. Hidden failures of the wire saw device are not manifested in the form of abnormalities in the sliced wafers sent out by the wire saw device, but correspond to a decrease in the yield of the wafers in the final product. The amount of loss caused by hidden faults corresponds to the reduction in the shipment amount of the final product caused by the decrease in the wafer yield of the final product.

Deterioration of the first part 11 can reduce the yield of the wafer of the final product and increase the amount of losses caused by hidden failures. The longer the operation time after maintenance is, the more serious the deterioration of the first part 11 will be, and the amount of loss caused by the hidden failure may also increase.

In order to reduce losses caused by hidden faults, it is effective to shorten the running time after maintenance.

<<Summary>>

Both the losses caused by obvious faults and the losses caused by hidden faults can be reduced by shortening the running time after maintenance. That is, failure costs can be reduced by shortening post-maintenance operating time.

<Loss function>

As described above, when the operation time after maintenance in the processing apparatus 10 is extended, the failure cost may increase although the management cost is reduced. On the other hand, when the operation time after maintenance is shortened, although the failure cost is reduced, the management cost is increased. That is, there is a trade-off between the management cost and the failure cost of the processing device 10 with respect to the operating time after maintenance.

The control unit 51 of the maintenance management device 50 can calculate the post-maintenance operating time to reduce the sum of management costs and failure costs. The sum of management costs and failure costs is represented by a loss function. The loss function is represented by the following equation (1), for example.

In Formula (1), L(u) is the value of the loss function using the post-maintenance operation time represented by u as a parameter. The first item on the right side of equation (1) expresses the management cost. C is a constant indicating the cost required to maintain the first part 11 . Also known as maintenance costs. Maintenance costs include replacement costs required to replace Part 11. The management cost of the first part 11 is inversely proportional to the inverse of the post-maintenance operation time, and the longer the post-maintenance operation time of the first part 11 is extended, the lower it becomes. The second item on the right side of equation (1) represents the failure cost. A is a constant representing the loss caused by apparent failure, also known as apparent failure loss. A’ is a constant that represents the loss caused by hidden faults, also called the loss caused by hidden faults. The - symbol appended above u indicates the mean time between apparent failures. The symbol with - above u will be marked as "u-" when it is used for explanation in the following articles.

C is the sum of the parts cost of the first part 11 (guide roller bearing), the labor cost of the regular replacement work of the first part 11, and the amount of opportunity loss. The labor fee is the product of the unit price of the labor fee and the operating time of regular replacement. The amount of lost opportunity is the product of the value of the sliced wafers that can be delivered per unit time and the operation time.

A represents the amount of money representing the value of one block processed as the workpiece W, the parts cost of the first part 11 (guide roller bearing), the labor cost of the repair work of the processing device 10 and the replacement work of the first part 11, and The total amount of opportunity lost. The labor fee is the product of the unit price of the labor fee and the operation time of repair and replacement. The amount of lost opportunity is the product of the value of the sliced wafers that can be delivered per unit time and the work time for repair and replacement. Repair and replacement operations take longer than periodic replacement operations. Therefore, labor charges for repair operations will be higher than for periodic replacement operations. In addition, the amount of opportunity loss caused by repair work will be higher than the amount of opportunity loss caused by regular replacement work.

A' is the production amount of wafers for the final product assuming a yield of 100%, the rate of decline in the yield of the wafers for the final product, the square of the time until the processing device 10 fails, and product of 1/2. Wafer yield is assumed to decrease at a rate proportional to post-maintenance run time. The product of the decline rate of the wafer yield of the final product, the square of the time until the processing device 10 fails, and 1/2 represents the accumulated yield decline until the processing device 10 fails.

The expression expressing the loss function is not limited to the above-mentioned expression (1), and may be expressed in other forms including terms respectively corresponding to manifest faults and hidden faults. The expression expressing the loss function may also be expressed as an expression including at least one of the above numbers C, A, and A'. The formula expressing the loss function is not limited to the above-mentioned C, A, and A', and may also be expressed by a formula including other constants.

The control unit 51 calculates the values of constants such as C, A, and A' included in the equation representing the loss function, and generates the loss function. The control unit 51 acquires parameters necessary for calculating the value of each constant. The parameters required to calculate the value of each constant are also called element parameters. The control unit 51 may obtain information on components such as the first component 11 constituting the processing device 10 as element parameters. Information about parts is also called part information. The control unit 51 may acquire information on labor management of workers who perform maintenance work such as repair work or parts replacement work on the processing device 10 as element parameters. Information about labor management of workers is also called labor management information. The control unit 51 may obtain information on the operating status of the processing device 10 , the number of production wafers, or the yield of wafers of the final product as element parameters. Information about operating conditions, the number of wafers produced, or the yield of wafers for final products is also called operating information. The control unit 51 may calculate each constant included in the equation representing the loss function based on the parts information, labor management information, or operation information, and generate the loss function.

Parts information, labor management information or operation information can also be stored in the maintenance DB of the non-operation server 70 . The control unit 51 may obtain labor management information or operation information as element parameters from the maintenance DB of the non-operation server 70 . The maintenance management device 50 may further include a communication device that can be connected to the non-running server 70 through wired or wireless communication. The non-running server 70 can also obtain parts information, labor management information or operating information from external devices and store them in the database. The non-operation server 70 may also store parts information, labor management information input by a manager, an operator of the processing device 10, a person in charge of maintenance, etc. Management information or operational information is stored in the database.

The control unit 51 may obtain operation information from the operation server 60 as element parameters. The maintenance management device 50 may also be further equipped with a communication device capable of communicating with the operation server 60 in a wired or wireless manner.

The control unit 51 may acquire the element parameters necessary for calculating the value of each parameter based on the user's input. The maintenance management device 50 may accept user input through the input unit 54 .

The control unit 51 calculates the value of each constant included in the equation representing the loss function based on the acquired element parameters, and generates the loss function. In this embodiment, the control unit 51 calculates the value of each constant in the above equation (1) to generate a loss function.

The maintenance management device 50 determines the replacement interval of the first component 11 so that the value of the loss function (L(u)) becomes smaller. FIG. 4 is a graph illustrating the relationship between post-maintenance operation time (u) and the value of the loss function (L(u)). In Figure 4, the horizontal axis represents the post-maintenance operating time (u). The vertical axis represents the value of the loss function (L(u)). The value of the loss function (L(u)) is shown in the solid line graph. The one-dot chain line graph and the dotted line graph respectively represent the values of the first and second terms on the right side of equation (1). The first item on the right corresponds to management cost, expressed as L _A (u). The second item on the right corresponds to the failure cost, expressed as L _B (u). L(u)=L _A (u)+L _B (u) holds. The value of the loss function can correspond to a value expressed by converting the size of the loss into monetary amounts.

Illustrated according to Figure 4. The graph of L(u) shows that the value of the loss function becomes a minimum at the point u=u ₁ . The minimum value is represented by L ₁ . L ₁ =L(u ₁ ) holds. When the loss function is expressed by equation (1), the post-maintenance operation time (u ₁ ) when the value of the loss function (L(u)) becomes the minimum value (L ₁ ) is expressed by the following equation (2).

The control unit 51 may determine the replacement interval of the first component 11 as u ₁ . The control unit 51 may determine the replacement interval of the first component 11 to be an interval longer than u ₁ or an interval shorter than u ₁ within a range in which the value of the loss function only increases within a predetermined value from the minimum value. In this way, the error of the loss function can be mitigated.

Furthermore, the control unit 51 may set the replacement interval of the first component 11 to an interval longer than u ₁ for the following reason. The change rate of the graph of the loss function is zero at the point where the value of the loss function becomes extremely small u=u ₁ . The rate of change of the graph of the loss function is negative at points u<u ₁ and positive at points u>u ₁ . The change rate of the graph of the loss function is expressed as a function that differentiates the loss function (L(u)) with respect to u. The function after differentiating (L(u)) once includes the reciprocal of the square of u. Therefore, the absolute value of the change rate of the graph of the loss function becomes smaller at the point u=u ₁ + △u than at the point u = u ₁ - △u. Here, △u is a positive constant. From this point of view, the amount of increase from the minimum value of the loss function value when the control unit 51 makes the replacement interval of the first component 11 longer than u ₁ will be smaller than when the replacement interval of the first component 11 is shorter than u ₁ In this case, the amount of increase from the minimum value of the loss function is small. That is, by setting the replacement interval of the first component 11 to an interval longer than u ₁ by the control unit 51 , the loss is less likely to increase.

The value of u when the loss function is a minimum value will be consistent with the value of u when the formula obtained by differentially dividing the loss function with respect to u is 0. The control unit 51 may generate in advance an equation in which the loss function is differentiated once with respect to u. This allows the minimum value of the loss function to be easily calculated.

The control unit 51 may also determine the time when the first component 11 is to be replaced next based on the determined replacement interval and the time when the first component 11 was replaced last time.

The control unit 51 outputs information on the determined replacement interval of the first component 11 or the time when the first component 11 is to be replaced next time to the output unit 53 . Information about the replacement interval of the first part 11 or the time when the first part 11 is to be replaced next time is also called replacement information of the first part 11 . It is assumed that the 11th replacement information of the first part is also included in the maintenance information of the processing device 10 . The output unit 53 can output the maintenance information as visual information or auditory information and notify the person in charge of maintenance of the processing device 10 . processing The person in charge of maintenance of the device 10 can plan and execute the replacement operation of the first part 11 in the processing device 10 based on the maintenance information of the first part 11 .

The output unit 53 may output information to the processing device 10 . When the output unit 53 outputs information to the processing device 10, the processing device 10 may output an alarm to notify the replacement time of the first part 11 based on the acquired information, or the processing device 10 itself may cooperate with the replacement of the first part 11. Stop at the point in time.

The apparent failure loss includes the opportunity loss caused by the stoppage of the processing device 10 due to failure. The opportunity loss assumption is represented by A1. The apparent failure loss includes the defective loss caused by the failure of the processing device 10 and delivery of defective products. The bad loss assumption is represented by A2. Explicit failure losses include the cost of replacing failed parts. The replacement cost is assumed to be represented by A3.

The opportunity loss depends on the time the processing device 10 is stopped. In addition, the opportunity loss depends on the operating conditions when the processing device 10 is not stopped. For example, the higher the operation rate of the processing device 10 is during the predetermined period before the processing device 10 is stopped, the greater the opportunity loss of the processing device 10 is.

In this embodiment, the processing device 10 is assumed to be stopped for a predetermined period of time. The opportunity loss when the processing device 10 is stopped for a predetermined period of time is represented by A1. Furthermore, as mentioned above, the opportunity loss also depends on the operating conditions of the processing device 10 . In this embodiment, it is assumed that the coefficient is determined based on the operating conditions of the processing device 10 . The coefficient depending on the operating conditions of the processing device 10 is represented by a. Assume that the opportunity loss when the operation rate of the processing device 10 is 100% is represented by A1, and a corresponds to the operation rate of the processing device 10 . Assuming that the opportunity loss when the operation rate of the processing device 10 is 80% is represented by A1, a corresponds to the value of multiplying the operation rate of the processing device 10 by 1.25 (the reciprocal of 80%). By determining a as described above, the opportunity loss of the processing device 10 is represented by aA1.

Based on the above, in this embodiment, the apparent failure loss (A) is expressed by the following formula (3). In other words. The failure cost of the second term of the loss function is represented by a value including an opportunity loss (A1) multiplied by a coefficient (a) based on the operating conditions of the processing device 10 .

[Formula 3] A = aA 1+ A 2+ A 3 (3)

In addition, the loss function La reflects the coefficient (a) according to the operating conditions of the processing device 10, and is expressed by equation (4).

In the following description, the opportunity loss when the operation rate of the processing device 10 is expected to be 100% is represented by A1. Therefore, a corresponds to the operation rate of the processing device 10 . In this case, a is set to a value from 0 to 1.

The first term on the right side of the loss function represented by La(u,a) does not contain a, so it is expressed as La _A (u). The second item on the right contains a, so it is expressed as La _B (u,a). According to the above notation, La(u,a)=La _A (u)+La _B (u,a) holds.

The maintenance management device 50 determines the replacement interval of the first component 11 to reduce the value of the loss function (La(u,a)). The value of u when the value of La(u,a) becomes the minimum value is expressed by the following equation (5).

Considering that a corresponds to the operation rate of the processing device 10, when the current operation rate of the processing device 10 is lower than the expected operation rate at the time when the loss function occurs, the value of La (u, a) becomes the minimum value of u value becomes larger. On the contrary, when the current operation rate of the processing apparatus 10 is higher than the expected operation rate at the time when the loss function occurs, the value of u when the value of La (u, a) becomes the minimum value becomes smaller. By changing the loss function according to the current operation rate of the processing device 10 , the maintenance work of the processing device 10 can be performed at the time point when the value of La (u, a) according to the current operation rate of the processing device 10 becomes a minimum value. .

Hereinafter, the change in the value of La(u,a) when the operation rate of the processing apparatus 10 is expected to be 100% but the actual operation rate becomes low will be described. 5 shows, as a solid line, the curve of the loss function (La(u,1)) when the operation rate of the processing device 10 is expected to be 100% (a=1), and the actual operation rate of the processing device 10 becomes 20%. The curve of the loss function (La(u,0.2)) in the case of (a=0.2). The horizontal axis represents operation time (u) after maintenance. The vertical axis represents the value of the loss function (La(u,a)). The one-dot chain line represents the value of the first term on the right side of equation (4) (La _A (u)). The dotted line represents the value of the second term on the right side of equation (4) (La _B (u, a)).

The value of u when La(u,0.2) reaches the minimum value is represented by u _0.2 . The minimum value in this case is represented by La _0.2 . The value of u when La(u,1) reaches the minimum value is represented by u ₁ . The minimum value in this case is represented by La ₁ . The relationship between the values of u is u _0.2 > u ₁ . In addition, the relationship between the minimum values is La _0.2 <La ₁ .

When the operation rate of the processing device 10 is 20%, the maintenance management device 50 substitutes 0.2 into a and updates the loss function to La(u,0.2) that matches the current state. The maintenance management device 50 can update the replacement interval of the first part 11 to an interval (u 1 ) longer than the originally expected interval (u ₁ ) based on the value of u in which the updated loss function (La(u, 0.2)) becomes the minimum value. u _0.2 ).

Through the update of the loss function and replacement interval, the value of the loss function becomes La _0.2 . Assuming that the replacement interval is u ₁ as originally expected, the value of the loss function (La(u ₁ ,0.2)) that matches the current state is Lc. Lc is larger than La _0.2 L _D . If the replacement interval has been updated, the loss should be reduced to La _0.2 . If the replacement interval is maintained at an interval calculated based on the expected operation rate of 100%, the opportunity to reduce losses will be lost. In other words, by updating the replacement interval based on the actual operating rate, losses can be reduced.

On the contrary, even when the operation rate of the processing device 10 is higher than expected, the loss can be reduced by updating the replacement interval based on the actual operation rate.

As described above, the maintenance management device 50 can determine the replacement interval of the first part 11 of the processing device 10 based on the management cost, the apparent failure loss including opportunity loss, the hidden failure loss, and the operation rate of the processing device 10 , and manage the processing device 10 maintenance work. Thereby, the output of the processing device 10 can be reduced. loss of life.

As an example of the embodiment, a structure example in which the replacement interval of the first component 11 is determined based on the opportunity loss reflecting the operation rate of the processing device 10 has been described. The maintenance management device 50 can also determine the replacement interval of the first component 11 without generating a loss function. The maintenance management device 50 may, for example, obtain data on the operation rate of the processing device 10 from the operation server 60 and feedback the operation rate of the processing device 10 into the replacement interval of the first component 11 .

[Confirmation of cost reductions resulting from consideration of opportunity losses in determining replacement intervals]

Hereinafter, a specific example of cost reduction of the processing device 10 will be described. In this example, the average failure frequency (u-) when the operation rate of the processing device 10 is 100% is assumed to be one year. The replacement cost (C) of parts is assumed to be 2 million yen. The opportunity loss (A1) when the operation rate of the processing device 10 is 100% is assumed to be 5 million yen. The defective loss (A2) caused by the failure of the processing device 10 is assumed to be 1 million yen. The replacement cost (A3) of the parts of the processing device 10 is assumed to be 2 million yen.

Under the above premise, the optimal periodic replacement interval of parts when the operation rate of the processing device 10 is expected to be 100% is calculated to be 0.71 years (corresponding to u ₁ in FIG. 5 ). Here, when the actual operation rate of the processing device 10 is 20%, the optimal periodic replacement interval of the parts is calculated to be 1.00 years (corresponding to u _0.2 in Figure 5). In this case, the parts with the expected operation rate of 100% are calculated. If replaced every 0.71 years, the cost will increase. Compared with replacing parts every 1.00 years, the additional cost (corresponding to L _D in Figure 5) is 240,000 yen. In other words, by considering the opportunity loss and determining the replacement interval of the first part 11, a cost reduction of 240,000 yen can be achieved.

[Example of steps for maintenance and management methods]

The control unit 51 of the maintenance management device 50 may, for example, execute the maintenance management method including the steps of the flowchart illustrated in FIG. 6 . The control unit 51 can execute the illustrated maintenance management method to determine the replacement interval of the first component 11 of the processing device 10 based on the hidden failure loss and manage the maintenance work of the processing device 10 . The maintenance management method may be implemented as a maintenance management program executed by the control unit 51 . The steps shown in Figure 6 are an example and can be changed appropriately.

The control unit 51 acquires element parameters (step S1).

The control unit 51 sets the constant of the loss function (step S2). Specifically, the control unit 51 calculates and sets the constant of the loss function based on the element parameter values obtained in step S1. The control unit 51 estimates the operation rate of the processing device 10 and sets the value of a as a constant of the loss function. The control unit 51 may set the respective values of A1, A2, A3, C, and A' as constants of the loss function.

The control unit 51 determines the replacement interval of the first component 11 (step S3). Specifically, the control unit 51 may calculate the post-maintenance operation time of the first component 11 when the value of the loss function of the constant set in step S2 is the minimum value, and determine the calculated value as the replacement interval of the first component 11 .

The control unit 51 outputs maintenance information (step S4). Specifically, the control unit 51 may output the replacement interval of the first component 11 determined in step S3 as maintenance information. The control unit 51 may further obtain the time point when the first part 11 was last replaced, and determine the next replacement of the first part 11 based on the replacement interval of the first part 11 determined in step S3 and the time point when the first part 11 was last replaced. 11 time points. The control unit 51 may output the time when the first component 11 is replaced next as maintenance information. The control unit 51 may output the maintenance information to the output unit 53 of the maintenance management device 50 . The output unit 53 may notify the maintenance person in charge of the processing device 10 by displaying the acquired maintenance information on a display device or notifying it via a sound output device. The control unit 51 may output maintenance information to the processing device 10 . The processing device 10 may output an alarm notifying the replacement time of the first part 11 based on the acquired maintenance information, or the processing device 10 itself may stop in accordance with the replacement time of the first part 11 .

The control unit 51 determines whether the operation rate of the processing device 10 has changed (step S5). When the operation rate of the processing device 10 changes (step S5: YES), the control unit 51 returns to step S2 and updates the value of a as the constant of the loss function. When the operation rate of the processing device 10 does not change (step S5: NO), the control unit 51 ends execution of the steps in the flowchart of FIG. 6 . The control unit 51 may repeat the determination in step S5.

In the determination of step S5, the control unit 51 may set a threshold value for the change amount of the operation rate. When the operation rate change is greater than the threshold value, return to step S2 to update the value of a as the constant of the loss function. The threshold can be determined based on the impact of changes in operating rates on costs. Feedback of changes in operating rates into parts replacement intervals at a stage that has little impact on costs will increase the management burden. By setting a threshold value for the change amount of the operation rate, the management burden of replacement intervals of parts can be reduced.

As described above, according to the maintenance management method and the maintenance management program of this embodiment, it is possible to reflect the replacement interval of the first part 11 of the processing device 10 based on the opportunity loss that reflects the operation rate of the processing device 10 . Thereby, the maintenance cost of the processing apparatus 10 can be reduced. The result is reduced manufacturing plant losses.

A plurality of processing devices 10 may be installed in a manufacturing factory. By increasing the amount of loss reduction per processing device 10 to some extent, the amount of loss reduction for the entire manufacturing plant can be sufficiently increased.

In addition, when the quality data changes or the state of the processing device 10 changes, the maintenance management device 50 can update the loss function by changing only the value of the operation rate (a) of the processing device 10 without regenerating the loss function. This can reduce the computational load necessary to generate the loss function. That is, the load on the control unit 51 of the maintenance management device 50 can be reduced. As a result, the maintenance management device 50 can easily feedback the operation rate of the processing device 10 into the loss function.

In addition, the maintenance management device 50 can recalculate the management cost and the failure cost at a time point after the periodic replacement of the parts of the processing device 10, and extend or shorten the optimal periodic replacement interval.

Furthermore, the maintenance management device 50 may recalculate the optimal periodic replacement interval using an interval shorter than the optimal periodic replacement interval. The maintenance management device 50 may update the optimal periodic replacement interval only when the cost determined based on the recalculation result of the optimal periodic replacement interval is reduced by more than a predetermined threshold value from the cost before recalculation. This can reduce the complexity of management of the optimal periodic replacement interval.

[Other implementation types]

<Used for devices other than wire saw devices, or parts other than guide roller bearings>

In the embodiment described above, the first component 11 corresponds to the guide roller bearing. The first component 11 is not limited to the guide roller bearing, and may correspond to other components such as the guide roller 32, the swing roller 34, the contact roller 35, and the like. In addition to determining the replacement interval of the guide roller bearing, the maintenance management device 50 can also determine the replacement interval of other parts such as the guide roller 32, the swing roller 34, or the contact roller 35, as the replacement interval of the part 11, to manage the maintenance work of the processing device 10 .

Not only for one part, the maintenance management device 50 can also determine the replacement interval for a part group consisting of two or more parts, and manage the maintenance work of the processing device 10 . For example, parts other than the first part 11 constituting the processing device 10 are also called second parts. The maintenance management device 50 may determine the replacement interval for the parts group consisting of the first part 11 and the second part. When the first component 11 is a guide roller bearing, the second component may be a guide roller 32 . The combination of two or more parts included in the parts group is not limited to the above example.

In the embodiment described above, the processing device 10 corresponds to the wire saw device. The processing device 10 is not limited to a wire saw device and may correspond to other devices such as a grinding device. The maintenance work of the processing device 10 is not limited to the maintenance of the wire saw device. The maintenance management device 50 can also manage the maintenance of other devices such as a polishing device. When the processing device 10 is another device, the processed product corresponds to items other than sliced wafers.

[Consider latent failure losses in functions other than the loss function]

The maintenance management device 50 of the embodiment described above formulates the relationship between maintenance and opportunity loss of the processing device 10 as a loss function, and manages the maintenance work of the processing device 10 by reducing the value of the loss function. In addition to the loss function, the maintenance management device 50 may formulate the relationship between maintenance and loss of the processing device 10 using other functions. The maintenance management device 50 may generate a function that considers opportunity loss using a function based on the failure rate of the processing device 10, the amount of damage when a failure occurs, and the probability of missing a failure symptom, for example, as described in Japanese Patent Application Laid-Open No. 2004-152017. , managing processing equipment Maintenance.

<Maintenance management based on individual status of processing device 10>

As described above, in order to calculate appropriate maintenance intervals for the processing device 10 or the parts used in the processing device 10 , a loss function model including management costs and failure costs (explicit failure costs and hidden failure costs) is used. The failure cost is formulated based on the loss when the processing device 10 fails and the probability of the failure occurring. The failure cost can vary according to the quality of the processing device 10 or the differences in the environment in which the processing device 10 operates. When a loss function model is used that does not consider the quality of the processing device 10 or the difference in the environment in which the processing device 10 operates, the processing device 10 may be maintained at a time when the possibility of failure is high. In addition, the processing device 10 may malfunction before the processing device 10 is maintained. The following describes a structure for optimizing the maintenance interval of the processing device 10 and reducing the maintenance cost using a loss function model that takes into account the variation of the failure cost according to the quality of the processing device 10 or the difference in the environment in which the processing device 10 operates.

The maintenance management device 50 sets the mean failure interval (u-) of each of the plurality of processing devices 10 set in the step to be uniformly the same based on the result of statistically processing the maintenance performance data of each processing device 10 . However, each processing device 10 operates under different conditions. For example, processing device 10 operates in different environments. The environment in which the processing device 10 operates may include the air environment such as temperature and humidity of the place where the processing device 10 is installed, or the environment of incidental equipment such as a cooling water supply system or a processing material supply system to which the processing device 10 is connected. wait. again. Each processing device 10 can have individual differences. Individual differences in the processing device 10 are caused by various matters, such as the manufacturing work of the processing device 10 , the specifications of the processing device 10 , the total operating time of the processing device 10 , or the maintenance history of the processing device 10 . Processing devices 10 operating under different conditions have different susceptibility to failure. That is, each processing device 10 can have a different mean time between failures.

Therefore, the maintenance management device 50 can assume that the mean time between failures of each processing device 10 differs depending on characteristic factors such as differences in the environment of each processing device 10 or individual differences, and configure the maintenance management device 50 for each processing device 10. Set 10 to set a loss function that takes into account the mean time between failures of each processing device 10 .

Here, the processing device 10 is assumed to include a first processing device and a second processing device. The maintenance management device 50 calculates the initial value of the mean time between failures of each of the first processing device and the second processing device. The maintenance management device 50 acquires operation data when each of the first processing device and the second processing device is operated. The maintenance management device 50 estimates the operation time from maintenance to failure for each of the first processing device and the second processing device. The maintenance management device 50 updates the mean time between failures of each of the first processing device and the second processing device based on the comparison between the estimated operating time and the initial value of the mean time between failures. Specifically, the maintenance management device 50 makes the mean failure interval longer than the initial value when the estimated operation time is longer than the initial value of the mean failure interval, and makes the mean failure interval longer than the initial value when the estimated operation time is shorter than the initial value of the mean failure interval. The mean interval between failures is shorter than the initial value. Thereby, the mean time between failures of each of the first processing device and the second processing device can be updated to different values.

The maintenance management device 50 sets the mathematical expression of the loss function model for each of the first processing device and the second processing device. The maintenance management device 50 does not update the value of the mean interval between failures (u-) included in the second term on the right side of equation (1) of the loss function model, but instead generates the loss function model Lb as shown in the following equation (6). , which introduces the correction coefficient b used to correct the coefficient of the second term on the right.

In equation (6), the mean interval between failures (u-) is assumed not to change from its initial value. The situation where the actual mean time between failures is different from the initial value will be represented by the correction coefficient b. For example, a state in which the mean interval between failures changes from the initial value to p times the value is reflected in the loss function model by setting the correction coefficient b to 1/(pˆ2).

When the maintenance management device 50 lengthens the mean interval between failures (u-), the mean interval between failures (u-) is not changed, and instead the value of the correction coefficient b is set to a value smaller than 1. On the contrary, When the maintenance management device 50 shortens the mean interval between failures (u-), the mean interval between failures (u-) is not changed, and instead the value of the correction coefficient b is set to a value larger than 1. Thereby, the loss function model Lb will reflect the quality of the processing device 10 or the environment in which the processing device 10 operates.

The first term on the right side of the loss function represented by Lb(u,b) does not contain b, so it is marked Lb _A (u), and the second term on the right side contains b, so it is marked Lb _B (u,b). . According to the above notation, Lb(u,b)=Lb _A (u)+Lb _B (u,b) holds.

Next, the change in the value of Lb(u,b) when the mean interval between failures of the processing apparatus 10 is longer than the initial value will be described. 7 shows, as a solid line, a curve of the loss function (Lb(u,1)) in the case where the mean interval between failures of the processing device 10 is expected to remain at the initial value, and when the mean interval between failures of the processing device 10 becomes longer than the initial value and is corrected The curve of the loss function Lb(u,0.8) when the coefficient b becomes 0.8. The horizontal axis represents operation time (u) after maintenance. The vertical axis represents the value of the loss function (Lb(u,b)). The curve of a one-point lock line expresses the value of the first term on the right side of equation (6) (Lb _A (u)). The dotted curve represents the value of the second term on the right side of equation (6) (Lb _B (u,b)).

The value of u when Lb(u,0.8) reaches the minimum value is represented by u _0.8 . The minimum value in this case is expressed as Lb _0.8 . The value of u when Lb(u,1) reaches the minimum value is represented by u ₁ . The minimum value in this case is expressed as Lb ₁ . The relationship between the values of u will be u _0.8 > u ₁ . In addition, the minimum value relationship is Lb _0.8 <Lb ₁ .

When the mean time between failures of the processing device 10 becomes longer than the initial value and the correction coefficient b becomes 0.8, the maintenance management device 50 can substitute 0.8 into b and update the loss function to Lb(u, 0.8) that matches the current state. The maintenance management device 50 can update the replacement interval of the first part 11 to an interval (u 1 ) longer than the originally expected interval (u ₁ ) based on the value of u in which the updated loss function (Lb(u, 0.8)) becomes the minimum value. u _0.8 ).

By updating the loss function and replacement interval, the value of the loss function becomes Lb _0.8 . Lb _0.8 is smaller than the value of the loss function assuming that the replacement interval is maintained at the originally assumed u ₁ . Therefore, by updating the replacement interval based on the actual mean time between failures, losses can be reduced.

On the contrary, even when the mean time between failures of the processing device 10 is shorter than the initial value, the loss can be reduced by updating the replacement interval based on the actual mean time between failures.

As described above, the maintenance management device 50 can determine the replacement interval of the first part 11 of the processing device 10 based on the management cost, the apparent failure loss including opportunity loss, the hidden failure loss, and the mean failure interval of the processing device 10, and manage the processing. Maintenance work on the device 10. Thereby, the loss caused by the processing device 10 can be reduced.

As an example, a case where the replacement interval is updated in consideration of the mean interval between failures of the wire saw device as the processing device 10 will be described. It is assumed that the mean interval between failures of the wire saw device is updated from the initial value and set to 0.7 years. Assume that maintenance costs such as replacement of parts for the wire saw device cost 2 million yen. Also, assume that the opportunity loss when the wire saw device malfunctions and the loss caused by product defects is 8 million yen. The maintenance management device 50 sets the replacement interval of the wire saw device to 0.7 years based on the average failure rate of the wire saw device being set to 0.7 years.

Here, it is assumed that the current mean failure interval of the wire saw device is extended to an interval longer than 0.7 years. At this time, if the replacement interval of the wire saw device is set at 0.7 years, the maintenance time will be too early. When the maintenance time point is too early, the management cost of the first item on the right side of the loss function increases. As a result, overall losses increase. Therefore, the maintenance management device 50 decreases the correction coefficient b to reduce the failure cost of the second item on the right side of the loss function. Then, when the correction coefficient b is set to 0.8, it is assumed that the replacement interval at which the loss function reaches the minimum value becomes 0.8 years. The replacement interval was extended from 0.7 years to 0.8 years, thereby reducing the overall cost by 600,000 yen compared to the case where it was set at 0.7 years.

On the contrary, when the current mean time between failures of the wire saw device is shortened to less than 0.7 years, the overall cost can be reduced by increasing the correction coefficient b.

The maintenance management device 50 can repeatedly review the setting of the mean interval between failures for each processing device 10, that is, it can repeatedly review the correction coefficient b. The value of the correction coefficient b can be revisited repeatedly Enough to converge within a certain range. Specifically. When the correction coefficient b is set to an excessively small value, the processing device 10 may give a sign of failure earlier than the replacement interval or may malfunction. On the contrary, when the correction coefficient b is set to an excessively large value, the processing device 10 may give no sign of failure or may not malfunction at all even at the replacement interval.

The maintenance management device 50 may also set a stable range based on the result of repeatedly reviewing the value of the correction coefficient b, in which the value of the correction coefficient b when the probability of the correction coefficient b being updated in the direction of increasing is less than a predetermined probability is set as the upper limit. The value of the correction coefficient b when the probability that the correction coefficient b is updated in a smaller direction is less than a predetermined probability is the lower limit. The established probability can be set appropriately. The maintenance management device 50 may also determine whether to update the correction coefficient b when the correction coefficient b is within the range of the stable range so that the correction coefficient b is less likely to go outside the stable range. For example, when the correction coefficient b is changed within the stable range, the maintenance management device 50 may change the correction coefficient b based on the operation data of one period after the maintenance of the processing device 10 to before the next maintenance. When the maintenance management device 50 changes the correction coefficient b outside the stable range, the maintenance management device 50 may change the correction coefficient b based on the operation data of a plurality of cycles after the maintenance of the processing device 10 and before the next maintenance.

The maintenance management device 50 may calculate a statistical value such as an average value of the operating data for a plurality of cycles from the maintenance of the processing device 10 to the next maintenance, and review the value of the correction coefficient b based on the calculation result of the statistical value.

The maintenance management device 50 may generate a loss function (Lab(u, a, b)) that reflects both the coefficient a regarding the operation rate of the processing device 10 and the coefficient b regarding the mean interval between failures of the processing device 10 to manage the processing device 10 maintenance work.

The implementation forms of the present disclosure have been described based on the drawings and examples. It should be noted that those skilled in the art can make various modifications or modifications based on the present disclosure. Therefore, it is noted that these variations or modifications are also included in the scope of the present disclosure. For example, the functions included in each component or each step can be rearranged without logical contradiction, or multiple components or steps can be Either form one or separate them. The embodiments of the present disclosure have been described centered on the device, and the embodiments of the present disclosure can be implemented as a method including steps executed by each component of the device. The implementation form of the present disclosure can be implemented as a method, a program executed by a processor of a device, or a storage medium that stores a program. The scope of this disclosure should be understood to include these contents.

The figures of this disclosure are schematic diagrams. Scales etc. are not necessarily consistent with reality.

[Industrial Applicability]

According to the implementation form of the present disclosure, losses in the manufacturing steps can be reduced.

1: Maintenance management system

10: Processing device

11: Part 1 (Guide roller bearing)

50: Maintenance management system

51:Control Department

52: Ministry of Communications

53:Output Department

54:Input part

60:Run the server

70: Non-running server (maintenance DB)

Claims (6)

A maintenance management device, including: a control unit that determines maintenance information of a processing device that manufactures processed products; and an output unit that outputs the maintenance information determined by the control unit, wherein the control unit is based on the maintenance cost of the maintenance operation of the processing device. Cost, the cost of failure caused by the processing device, determines the maintenance information. The failure cost includes the opportunity loss caused by the failure of the processing device; among them, the control unit uses the post-maintenance operating time as a parameter to generate a loss function; the maintenance The post-operation time corresponds to the operation time of the processing device after the maintenance operation of the processing device, and the loss function is defined as the first term proportional to the product of the reciprocal of the post-maintenance operation time and the maintenance cost, and the The sum of the second item of the ratio of the product of the post-maintenance operating time and the failure cost; the control unit determines the maintenance information based on the loss function; wherein the control unit generates the loss function, and the second item of the loss function The failure cost of is expressed in a form including a value obtained by multiplying the opportunity loss by a coefficient based on the operating conditions of the processing device. The maintenance management device of claim 1, wherein the control unit calculates the post-maintenance operation time when the value of the loss function becomes a minimum value or when the minimum value is within a predetermined value range. , as the maintenance information. The maintenance management device of claim 1, wherein the control unit generates the loss function in the form of multiplying the failure cost of the second item of the loss function by a coefficient based on the characteristic factor of the processing device. Such as the maintenance management device of claim item 1 or 2, wherein: The control unit generates the loss function in the form of multiplying the failure cost of the second term of the loss function by a coefficient based on the characteristic factor of the processing device. A maintenance management method, including: a step in which a maintenance management device determines maintenance information of a processing device that manufactures processed products, which is determined based on the maintenance cost of the maintenance operation of the processing device and the cost of failure caused by the processing device; And the step of the maintenance management device outputting the determined maintenance information, wherein the failure cost includes the opportunity loss caused by the failure of the processing device; wherein the maintenance management device uses the post-maintenance operation time as a parameter to generate a loss function; the maintenance The post-operation time corresponds to the operation time of the processing device after the maintenance operation of the processing device, and the loss function is defined as the first term proportional to the product of the reciprocal of the post-maintenance operation time and the maintenance cost, and the The sum of the second item of the ratio of the product of the post-maintenance operating time and the failure cost; the maintenance management device determines the maintenance information based on the loss function; wherein the maintenance management device generates the loss function, and the second term of the loss function The failure cost of item 2 is expressed in a form including a value obtained by multiplying the opportunity loss by a coefficient based on the operating status of the processing device. A maintenance management program is executed by a processor to perform the following steps. The aforementioned steps include: the step of determining maintenance information of a processing device for manufacturing processed products, which is based on the maintenance cost and cause of the maintenance operation of the processing device. Determined based on the failure cost of the processing device; and the step of outputting the determined maintenance information, wherein the failure cost includes the opportunity loss caused by the failure of the processing device; Among them, the post-maintenance operation time is used as a parameter to generate a loss function; the post-maintenance operation time corresponds to the operation time of the processing device after the maintenance operation, and the loss function is defined as the reciprocal of the post-maintenance operation time. and the sum of the first item that is proportional to the product of the maintenance cost, and the second item that is proportional to the product of the post-maintenance operating time and the failure cost; the maintenance information is determined based on the loss function; where the loss occurs function, and the failure cost of the second term of the loss function is expressed in a form including a value obtained by multiplying the opportunity loss by a coefficient based on the operating status of the processing device.

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