WO2014155848A1

WO2014155848A1 - Manufacturing facility control device

Info

Publication number: WO2014155848A1
Application number: PCT/JP2013/082854
Authority: WO
Inventors: ▲隆▼一郎高市; 一志山▲崎▼
Original assignee: オムロン株式会社
Priority date: 2013-03-25
Filing date: 2013-12-06
Publication date: 2014-10-02
Also published as: JP6119357B2; JP2014186656A

Abstract

A control device comprises: a storage device which stores a setting value of a return time; a mode switch unit which, when a manufacturing facility is in a standby mode, determines, on the basis of a scheduled manufacturing start time and the setting value of the return time, a switch time whereat a switch from the standby mode to an operation mode is to be carried out, and carries out the switch from the standby mode to the operation mode at the time whereat the present time has reached the switch time; a measurement unit which measures the return time actually required to return to the previous state after the switch to the operation mode by the mode switch unit; and an update unit which, on the basis of the measurement value of the return time which is measured by the measurement unit, updates the setting value of the return time which is stored in the storage unit.

Description

Production equipment control equipment

The present invention relates to control of production equipment, and more particularly to technology for reducing energy consumption of production equipment.

省エネ Energy-saving technologies in production facilities such as factories are attracting attention because of environmental issues and cost reduction requirements. For example, even when the manufacturing equipment is in operation, production is not always performed, and there are many times when the equipment is idle, such as when the operator is absent during breaks and shifts, and during setup changes. . However, since it takes a considerable amount of time to start up the manufacturing apparatus, the manufacturing apparatus cannot be completely stopped during line operation. Therefore, recently, when idling (during non-production), the system is put on standby with low energy consumption (called standby mode, energy-saving mode, etc.), and switched to the operation mode when production resumes, so that production is possible. An apparatus capable of energy saving control such as quick return has been proposed (see, for example, Patent Documents 1 to 3).

JP 2010-147112 A JP 2010-282392 A Japanese Patent No. 5077475

In the energy saving control as described above, how to control the timing for switching from the standby mode to the operation mode is one of the technical problems. Production cannot be resumed immediately after switching to the operation mode, and a certain amount of waiting time (this is called return time) is required before it becomes possible to manufacture with stable quality. is there. Moreover, the recovery time is not always constant, and may vary depending on the state of the equipment at the time of mode switching (in the case of a heating furnace, the temperature and atmosphere in the furnace) and the installation environment (ambient temperature, humidity, etc.). is there. Therefore, in the past, a time much longer than the expected return time is given as a set value, and mode switching is performed when the set value is traced back from the scheduled production start time, so that the status is reached by the scheduled production start time. He was sure to return. However, in this method, the state recovery is often completed well before the scheduled production start time, and wasteful energy consumption occurs between the state recovery and the production restart, so there is room for further reduction. .

The present invention has been made in view of the above circumstances, and an object thereof is to provide a technique for further reducing the energy consumption of production equipment. A further object of the present invention is to provide a technique for automatically setting an appropriate return time according to the operating conditions and installation environment of the production facility.

In order to achieve the above object, the present invention measures the actual time required for the state to actually return after mode switching, and automatically updates the set value of the return time based on the measured value. adopt.

Specifically, the control device according to the present invention includes an operation mode that maintains a first state in which production is possible, and a standby mode that stands by in a second state in which energy consumption is lower than the first state. A storage unit that stores a set value of a return time expected to be required for the production facility to return from the second state to the first state, and the production facility Is switched from the standby mode to the operation mode based on the time when the production facility should be returned to the first state and the set value of the return time stored in the storage unit. The mode switching unit that determines the switching time to be switched and switches from the standby mode to the operation mode when the current time reaches the switching time, and the mode switching unit is switched to the operation mode, Based on the measured value of the return time measured by the measuring unit and the measuring unit that actually measures the return time required for the production facility to return to the first state, And an update unit for updating the set value of the return time.

According to this configuration, it is possible to suppress wasteful energy consumption by switching the production facility to the standby mode when the operator is absent due to a break or shift shift, or when production is temporarily stopped due to setup change or the like. it can. Switching to the standby mode may be instructed manually by an operator or may be switched automatically. Here, “energy” includes not only energy (electric power, heat, power, etc.) directly supplied to the production facility, but also energy necessary for operating the production facility, for example, production facility. It may include energy necessary for manufacturing, transporting, storing, and supplying substances (eg, atmospheric gas, cooling liquid, cleaning liquid, and catalyst) used in

Switching from standby mode to operation mode is automatically executed by the mode switching unit. The mode switching timing (switching time) is determined based on the time at which the production facility should be returned to the first state (hereinafter referred to as the scheduled production start time) and the set value of the return time preset in the storage unit. It is done. Here, by taking a certain margin into the set value of the return time, the production equipment is returned to the first state (a state where production is possible) by the scheduled production start time, and production is resumed. Can be guaranteed.

Furthermore, in the present invention, a configuration for automatically optimizing the set value of the return time is adopted. That is, after the mode is switched, the return time actually required until the first state is returned is measured, and the set value of the return time is updated based on the measured value (actually measured value). For example, if the set value is excessive compared to the measured value, the set value can be shortened. If the difference (margin) between the measured value and the set value is too small, the set value can be increased. Good. As long as the set value can be updated to a better value based on the measurement value, the update process may be performed by any algorithm. With this configuration, the set value of the return time can be automatically optimized while the production facility is actually operated (that is, online). In addition, due to differences in operating conditions, installation environment, aging, etc., there may be variations in the return time even with the same production equipment, but by updating the set values appropriately based on the measured values as in the present invention, the production equipment An appropriate return time can be set automatically every time. Therefore, the idling time from the return to the first state to the resumption of production can be shortened as much as possible, and wasteful energy consumption can be reduced.

It is preferable that the update unit determines a new set value for the return time based on a statistical value of a plurality of measurement values. The recovery time may vary depending on the state of the production equipment and the installation environment at the time of mode switching, but the set value is determined in consideration of the variation in the recovery time by using the statistical values of the measured values for multiple times. It becomes possible to do. As the statistical value, any value may be used as long as it is an index representing variation (distribution) of measured values, such as an average value, variance, standard deviation, maximum value, and mode value.

Each time measurement is performed by the measurement unit, a measurement value is recorded in the storage unit, and the update unit measures a plurality of times measured in a predetermined period from all the measurement values recorded in the storage unit. It is preferable to extract a value and determine a new set value for the return time based on the extracted statistical values of the measured values for a plurality of times. For example, when the recovery time changes due to equipment aging, seasonal fluctuations, etc., rather than using all the accumulated measurement values from the past, only some measurement values (most recent measurement values, simultaneous measurement values, etc.) It is possible to obtain a more appropriate set value by using.

If the set value optimized by the update process of the present invention is used, in most cases, the return of the state can be completed by the scheduled production start time. However, in rare cases, it is not without the risk that state recovery will not be in time by the scheduled production start time. Therefore, the control device further includes an input unit that receives an input of an additional time from a user, and when the mode switching unit determines the switching time, or the update unit sets a set value of the return time. When updating, it is preferable that the input additional time is added to the set value of the return time. Thereby, the switching time from the standby mode to the operation mode can be advanced by the additional time. Although there is a disadvantage that energy consumption increases slightly due to the addition of additional time, energy saving control resumes production by setting an appropriate additional time (margin for safety) based on the experience and knowledge of the user. The advantageous effect of eliminating the risk of hindering the operation is obtained.

It is preferable to further include an initialization unit for returning the set value of the return time stored in the storage unit to the initial value. As a result, the optimized (learned) return time setting value can be reset as necessary, and the learning can be performed again from the beginning, improving convenience. This function is effective when the recovery time fluctuates for some reason (that is, when the set value learned by the past measurement value becomes invalid).

For example, if the production equipment configuration is changed (including repairs, parts replacement, installation location changes) or operating conditions (control target values, control logic, etc.) are changed, There is a high possibility that the set value learned from the measured value is not valid. Therefore, it is preferable that the initialization unit returns the set value of the return time to the initial value when the configuration of the production facility or the operation condition is changed. Thereby, it is possible to prevent mode switching based on an invalid setting value from being performed.

The control device according to the present invention can be applied to any kind of production equipment as long as the production equipment has an operation mode and a standby mode. The production equipment refers to equipment related to the production of products, and typically includes manufacturing equipment and processing equipment, but equipment that indirectly contributes to production also corresponds to production equipment.

As one of the production equipment corresponding to the manufacturing equipment and processing equipment, there is a reflow furnace for heating the solder paste on the substrate. In the case of a reflow furnace, the operation mode is a mode in which nitrogen gas is supplied into the furnace and the oxygen concentration in the furnace is maintained in the first state, and the standby mode is to stop the supply of nitrogen gas. In this mode, the supply amount is reduced. Alternatively, the operation mode is a mode in which electric power is supplied to the heater in the furnace and the temperature in the furnace is maintained in the first state, and the standby mode is to stop or supply electric power to the heater. This mode reduces the amount.

Also, one of the production equipment that corresponds to equipment that indirectly contributes to production is a clean room for keeping the production environment clean. In the case of a clean room, the operation mode is a mode in which power is supplied to the fan filter unit and the cleanliness in the clean room is maintained in the first state, and the standby mode is supply of power to the fan filter unit. This mode stops the supply or decreases the supply amount.

Note that the present invention can be understood as a control device having at least a part of the above-described configuration or a production facility including the control device. The present invention can also be understood as a control method for a control device including at least a part of the above processing, a program for causing the control device to execute the method, or a computer-readable recording medium on which the program is recorded. . Each of the above configurations and processes can be combined with each other as long as no technical contradiction occurs.

According to the present invention, the energy consumption of the production facility can be further reduced. In addition, it is possible to automatically set an appropriate return time according to the operating conditions of the production equipment, the installation environment, and the like.

1 is a diagram illustrating an overall configuration of a substrate processing system according to a first embodiment. The figure which shows the structure of a reflow furnace typically. The control block diagram of a reflow furnace. The figure for demonstrating the energy saving control by mode switching. The block diagram which shows the structure of the function in connection with the energy saving control of a controller. The figure which shows the whole flow of the process performed by a controller. The figure which shows the flow of an initialization process. The figure which shows the processing flow in standby mode. The figure which shows the flow of the update process of the setting value of return time. The figure which shows an example of the mode switching timing at the time of using the set value of the updated (learned) return time. The figure which shows the whole structure of the clean room of 2nd Embodiment.

The present invention relates to a control device that performs energy saving control of a production facility and a control method thereof. The control device may be a separate unit or an external unit from the production facility, or may be a unit integrated with or built in the production facility. The control device can be applied to all types of production facilities as long as the production facilities have an operation mode and a standby mode. Production equipment refers to equipment related to product production, typically manufacturing equipment and processing equipment, but equipment that indirectly contributes to production, such as transportation equipment, storage equipment, clean rooms, Air conditioners, lighting devices, etc. also fall under production facilities. In the following embodiments, as a preferable application example of the present invention, energy saving control of a reflow furnace for heating a solder paste on a substrate and energy saving control of a clean room for keeping a production environment clean are exemplified.

<First Embodiment>
1st Embodiment of this invention is an example which applied this invention to the energy saving control of the reflow furnace of a substrate processing system. First, a schematic configuration of the system will be described with reference to FIG. 1, FIG. 2, and FIG. FIG. 1 is a diagram showing an overall configuration of a substrate processing system, FIG. 2 is a diagram schematically showing a configuration of a reflow furnace, and FIG. 3 is a control block diagram of the reflow furnace of FIG.

(Substrate processing system)
The substrate processing system in FIG. 1 is a system for mounting electronic components on a printed circuit board.

In the substrate processing system of FIG. 1, a printed circuit board to be processed is sent in the order of a loader 210, a solder printer 220, an inspection device 230, a high-speed mounter 240, a high-precision mounter 250, an inspection device 260, a reflow furnace 100, and an unloader 310. . An arrow D1 in FIG. 1 indicates the conveyance direction of the printed board.

Solder paste is printed by the solder printer 220 on the printed circuit board sent from the loader 210. After the quality of the printing is inspected by the inspection device 230, the electronic component is mounted on the printed circuit board by the high-speed mounter 240 and the high-precision mounter 250. After the quality of the mount is inspected by the inspection device 260, the printed circuit board on which the electronic component is mounted is sent to the reflow furnace 100. In this specification, the printed circuit board mounted with the electronic components sent to the reflow furnace 100 is referred to as “work”.

Then, after the solder paste is dissolved and the electronic component is fixed in the reflow furnace 100, the workpiece is sent to various processes via the unloader 310.

Note that the loader 210, solder printer 220, inspection device 230, high-speed mounter 240, high-precision mounter 250, inspection device 260, reflow furnace 100, and unloader 310 are

emergency lamps

219, 229, 239, 249, 259, and 269. , 109 and 319, and their operations are controlled by respective control devices. And when the emergency occurs in each, the said control apparatus makes the emergency lamp corresponding to each apparatus light.

(Reflow furnace)
The configuration of the reflow furnace 100 will be described in detail with reference to FIG. In the reflow furnace 100, the workpiece 90 sent from the inspection apparatus 260 is placed on the conveyor 80 and is conveyed in the reflow furnace 100. An arrow D2 in FIG. 2 indicates the rotation direction of the conveyor 80 (note that the left and right sides of the reflow furnace 100 are reversed in FIGS. 1 and 2 for the purpose of illustration).

An inert atmosphere chamber 13 is provided in the reflow furnace. A duct 56A is provided on the upstream side of the inert atmosphere chamber 13, and a duct 56B is provided on the downstream side.

The

ducts

56A and 56B are provided with

fans

50A and 50B and opening /

closing plates

52A and 52B, respectively.

Fans

50A and 50B are driven by

motors

51A and 51B, and

motors

51A and 51B are supplied with electric power from

inverters

55A and 55B.

The opening /

closing plates

52A and 52B are provided to adjust the degree of air flow in each of the

ducts

56A and 56B. The degree of opening and closing of the air passages in the

ducts

56A and 56B by the opening and

closing plates

52A and 52B is controlled by

damper motors

53A and 53B, respectively.

When it is desirable to reduce the oxygen concentration, such as when the solder used in the workpiece 90 is a so-called lead-free solder, the inert atmosphere chamber 13 is provided with a nitrogen line 14 in order to reduce the oxygen concentration. Nitrogen gas (also referred to as inert gas or atmospheric gas) is sent through. The amount of nitrogen gas introduced into the inert atmosphere chamber 13 is controlled by controlling the degree of opening and closing of a nitrogen valve (hereinafter also referred to as “N2 valve”) 16. The flow rate of nitrogen gas in the nitrogen line 14 is detected by a flow meter 15. Further, the reflow furnace is provided with an oxygen concentration sensor (hereinafter also referred to as “O2 concentration sensor”) 17 for detecting the oxygen concentration in the inert atmosphere chamber 13.

In the inert atmosphere chamber 13, in order to heat the workpiece in seven stages,

heaters

11A and 11B, heaters 11C and 11D, heaters 11E and 11F, heaters 11G and 11H, heaters 11I and 11J,

heaters

11K and 11L, and

heater

11M , 11N, 7 sets of heating devices are provided. Each set of heating devices includes a heater disposed above the conveyor 80 and a heater disposed below. In the reflow furnace, the power consumed by the heaters 11A to 11N is measured by the wattmeter 70.

Further, in the vicinity of each heater, in order to stir the air in the inert atmosphere chamber 13, the

fans

12A and 12B, the

fans

12C and 12D, the

fans

12E and 12F, the fans 12G and 12H, the fans 12I and 12J, and the fan 12K. , 12L and

fans

12M, 12N are provided.

In the inert atmosphere chamber 13, the work 90 heated by the

heaters

11A and 11B, the heaters 11C and 11D, the heaters 11E and 11F, the heaters 11G and 11H, the heaters 11I and 11J, the

heaters

11K and 11L, and the

heaters

11M and 11N 56B and cooled by the chiller 60. The chiller 60 includes cooling

pipes

61 and 62. Thereafter, the workpiece 90 is sent to the next step (for example, the unloader 310 in FIG. 1).

In the inert atmosphere chamber 13 and the duct 56B, a temperature sensor (not shown) is provided. The temperature control unit 102 feedback-controls the operation of the heaters 11A to 11N based on the temperature detected by the temperature sensor. Further, the reflow furnace includes a controller (control device) 101 for overall control of the operation of each element such as the heaters 11A to 11N and the nitrogen valve 16 on the basis of detection outputs of the temperature sensor 22 and the oxygen concentration sensor 17. Is provided.

The controller 101 is provided in a process prior to the reflow furnace 100 in a substrate processing system (see FIG. 1) such as a personal computer (hereinafter also referred to as “PC”) 300 that functions as a monitor and

inspection apparatuses

230 and 260. A device (controller 200) for controlling the connected device is connected. As will be described later, the controller 101 may control the operation of each element such as the heaters 11A to 11N and the nitrogen valve 16 based on information acquired from the PC 300 and the controller 200.

(Reflow furnace control block)
FIG. 3 shows a control block of the reflow furnace 100. In addition to the elements such as the heaters 11A to 11N described with reference to FIG. 2, the controller 101 includes the atmospheric temperature in each of the seven stages of heating processes (each heater group) in the inert atmosphere chamber 13 and the work of the duct 56B. 90, a temperature sensor 22 for detecting the ambient temperature in the vicinity of the passing region, a substrate sensor 21 for detecting the number of substrates introduced into the inert atmosphere chamber 13, a conveyor motor 81 for rotating the conveyor 80, and FIG. 1 is connected to the emergency lamp 109 described with reference to FIG. Note that FIG. 3 shows that the temperature control unit 102 of FIG. 2 is included in the controller 101.

Based on the detection output of the temperature sensor 22, the controller 101 maintains the heating operation of the heaters 11A to 11N at a temperature determined for each heating process by feedback control such as PID (Proportional Integral Differential) control. ,Control. Further, the controller 101 feedback-controls the degree of opening and closing of the nitrogen valve 16 based on the detection output of the oxygen concentration sensor 17 so that the oxygen concentration in the inert atmosphere chamber 13 is equal to or lower than a predetermined concentration. Further, the controller 101 controls the cooling mode of the atmosphere in the duct 56 </ b> B, such as the circulation amount of the refrigerant in the cooling

pipes

61 and 62 in the chiller 60 based on the detection output of the ambient temperature in the duct 56 </ b> B by the temperature sensor 22. Target values (operating conditions) in each control are set in advance in the controller 101.

In addition, the controller 101 cannot normally execute a scheduled operation in the substrate processing system, such as when the temperature in the inert atmosphere chamber 13 rises abnormally, or when the conveyor 80 transports the work 90. When a situation occurs, the emergency lamp 109 is turned on after taking known measures such as stopping the heating by the heaters 11A to 11N and stopping the conveyance of the work 90 by the conveyor 80. In response to this, after removing the trouble in the reflow furnace, the worker takes measures such as resetting the controller 101 and restarting the operation of the reflow furnace.

The controller 101 is used for communication between an arithmetic unit 101A such as a CPU (Central Processing Unit), a memory 101B for storing various data such as programs, and the PC 300, the controller 200, and the controller 101 described above. And an interface 101C. The interface 101C is realized by a communication device such as a network card. Then, when the arithmetic unit 101A executes, for example, a program stored in the memory 101B, a control operation by the controller 101 as described in this specification is realized. However, the controller 101 may be realized by including one or more hardware devices (such as LSI (Large Scale Integration)) that realize each function of the controller 101.

Note that the memory 101B may be realized by a storage medium that is detachable from the main body of the controller 101. Such storage media include CD-ROM (Compact Disk--Read-Only Memory), DVD-ROM (Digital Versatile Disk--Read-Only Memory), USB (Universal Serial Bus) memory, memory card, FD (Flexible Disk), Hard disk, magnetic tape, cassette tape, MO (Magnetic Optical Disk), MD (Mini Disk), IC (Integrated カード Circuit) card (excluding memory card), optical card, mask ROM, EPROM, EEPROM (Electronically Erasable Programmable Read-Only A medium for storing the program in a nonvolatile manner such as Memory).

(Energy saving control of reflow furnace)
During the operation of the substrate production line, in principle, the state of the reflow furnace 100 is a state in which the workpiece 90 can be produced (heat treated) with stable quality (this is referred to as a “manufacturable state” or a “first state”). ) Must be maintained. However, the workpiece 90 to be processed is not always flowing. For example, when the operator is absent due to a break or shift shift, the time for setup change, or when an abnormality occurs, the workpiece 90 is temporarily put in. Sometimes it stops. Therefore, the reflow furnace 100 according to the present embodiment has an operation mode that is a mode for maintaining the production possible state, and a state in which energy consumption is lower than that in the production possible state (referred to as “standby state” or “second state”). The controller 101 switches to the standby mode as necessary to suppress energy consumption during non-production. In the standby mode, for example, by stopping the supply of nitrogen gas (or reducing the supply amount), stopping the supply of electric power to the heaters 11A to 11N (or reducing the supply amount), etc., energy consumption is reduced. It is suppressed. In addition, driving of a fan, a motor, or the like may be stopped. Nitrogen gas itself is not energy, but if the consumption of nitrogen gas is reduced, energy and cost required for production, transportation, storage, supply, etc. of nitrogen gas can be reduced. This is regarded as one of the energy consumed by the reflow furnace 100.

Fig. 4 shows an example of energy saving control by mode switching. The upper graph in FIG. 4 shows the change over time in the flow rate of nitrogen gas, and the lower graph shows the change in oxygen concentration in the inert atmosphere chamber 13 over time.

In the operation mode, the controller 101 adjusts the opening degree of the nitrogen valve 16 (that is, the flow rate of nitrogen gas) based on the output of the oxygen concentration sensor 17, thereby adjusting the oxygen concentration in the inert atmosphere chamber 13 to a predetermined management value ( Here, it is maintained at 4000 ppm). If the oxygen concentration is about 4000 ppm or less, oxidation of metal parts on the workpiece 90 can be prevented, and stable quality can be ensured.

When the work 90 is temporarily stopped, the controller 101 switches the mode of the reflow furnace 100 from the operation mode to the standby mode, and stops the supply of nitrogen gas. Thereby, useless consumption of nitrogen gas can be reduced.

In order to resume production, the controller 101 switches from the standby mode to the operation mode, and resumes supply of nitrogen gas and control of oxygen concentration. However, as shown in FIG. 4, even if the supply of nitrogen gas is resumed, the oxygen concentration does not decrease immediately, and it takes a certain amount of time for the oxygen concentration to fall to about 4000 ppm and to be ready for production. . The time required from when the operation mode is switched to (time T0) until the oxygen concentration reaches the production-capable state (time T1) is referred to as return time RT (= T1-T0). Depending on the device configuration and operating conditions, a recovery time RT of about several minutes to ten and several minutes is required.

From the viewpoint of energy saving, it is preferable to set the mode switching timing (time T0) so that the difference between the time T1 for returning to the production ready state and the production start scheduled time T2 is as small as possible. Nonetheless, if the oxygen concentration does not recover in time, the resumption of production will be hindered. From the viewpoint of production efficiency, the mode switching timing should be set earlier and the time between times T1 and T2 It is desirable to make a margin. In addition, the recovery time is not always constant, and may vary depending on the state of the furnace (oxygen concentration, temperature, etc.) and the installation environment (ambient temperature, humidity, etc.) at the time of mode switching. Therefore, even for an experienced operator, it is difficult to manually set the mode switching timing to an appropriate value.

Therefore, in the present embodiment, the actual time required until the controller 101 actually returns to the production-ready state after switching the mode is measured, and the set value of the return time is automatically updated (learned) based on the measured value. Thus, the mode switching timing is optimized. Hereinafter, a specific configuration of energy saving control by the controller 101 will be described in detail.

(Functional block for energy saving control)
FIG. 5 is a block diagram illustrating a configuration of functions related to energy saving control of the controller 101. The functions related to energy saving control include a storage unit 110, a mode switching unit 111, a control unit 112, a measurement unit 113, an update unit 114, an input unit 115, and an initialization unit 116. The storage unit 110 has a function of storing a set value of recovery time, a measured value, a statistical value obtained by calculation, log data, and the like, and is realized using the storage device of the memory 101B or the PC 300. The mode switching unit 111 is a function for switching the operation mode (operation mode / standby mode) of the reflow furnace 100. The control unit 112 has a function of controlling each element of the reflow furnace 100 according to the operation mode instructed from the mode switching unit 111. The measuring unit 113 has a function of measuring the actual time required from the mode switching to returning to the production possible state by using a timer. The update unit 114 is a function for updating the set value of the return time based on the measurement value obtained by the measurement unit 113. The input unit 115 is a function that receives information input from the user. A user interface through which a user inputs information is provided by the PC 300. The initialization unit 116 is a function for initializing data stored in the storage unit 110.

These functions are realized when the arithmetic unit 101A executes a program stored in the memory 101B. However, part or all of the functions may be realized by the PC 300 or may be realized by a logic circuit.

(Energy saving control flow)
Next, operations of functions related to energy saving control will be described with reference to FIGS. 6 shows the overall flow of processing executed by the controller 101, FIG. 7 shows the flow of initialization processing executed by the initialization unit 116, and FIG. 8 shows the processing flow in standby mode. Reference numeral 9 denotes a flow of processing for updating the set value of the return time.

As shown in FIG. 6, when the controller 101 is activated, the initialization unit 116 first determines whether or not an initialization process is necessary (step S60). The initialization process is a process for resetting data stored in the storage unit 110. For example, when the valve of the reflow furnace 100 is replaced or the control target value (management value) is changed, the return time from the mode switching changes due to the influence, and the past measurement values and setting values become invalid. there is a possibility. The initialization process is executed in such a case. Specific implementation methods have an impact on recovery time, such as changes in production equipment configuration (for example, repairs, parts replacement, installation location changes) and operating conditions (for example, control target values or control logic changes). When an operation that can be given is performed, an initialization flag required is set in the controller 101 automatically or manually, and the initialization unit 116 determines whether or not initialization processing is necessary based on the presence or absence of this flag. Or the screen which confirms the necessity of an initialization process may be shown on the monitor of PC300 by the input part 115, and a user may be made to input necessity.

If it is determined in step S60 that the initialization process is necessary, the initialization unit 116 executes the initialization process (step S61). As shown in FIG. 7, the initialization unit 116 resets the counter n indicating the number of measurements to 0 (step S70), and the return time measurement value RT accumulated so far and the average value that is a statistical value thereof. RTA and standard deviation σ are cleared (erased) (step S71). In the following description, the i-th measurement value is expressed as RTi, and the average value and standard deviation obtained from the n-time measurement values RT1 to RTn are expressed as RTAn and σn, respectively. Further, the initialization unit 116 returns the set value RTS of the return time to the initial value (step S72). The initial value is set to a value sufficiently larger than the assumed recovery time (for example, twice the assumed time). This is because at the initial stage, it is unclear how long the restoration will actually be completed.

Thereafter, the control unit 112 starts control in the operation mode (step S62). When the in-furnace temperature, oxygen concentration, cooling temperature of the chiller 60, etc. satisfy predetermined conditions and become ready for production, the input of the workpiece is started from the upstream process and reflow processing is performed.

When a command to switch to standby mode (interrupt) occurs during execution of the operation mode (step S63), the mode switching unit 111 performs switching processing to the standby mode (step S64). The standby mode switching command (interrupt) is generated, for example, when a predetermined switch is operated by the user or when a preset time (break start time, shift change time, etc.) is reached. .

Details of the processing in step S64 are shown in FIG. The mode switching unit 111 reads the return time setting value RTS stored in the storage unit 110 (step S80). Further, the mode switching unit 111 presents an input screen on the monitor of the PC 300 via the input unit 115, and accepts input of the production start scheduled time ST and the allowance time AT (steps S81 and S82). The scheduled production start time ST is a time when the input of the workpiece into the reflow furnace 100 is resumed. Further, the margin time AT is a margin (additional time) added to the return time, and an arbitrary value can be set by the user. Note that it is not essential to input the scheduled production start time ST and the allowance time AT. If these values are set in advance or if no allowance time is provided, the processes in steps S81 and S82 may be omitted. .

Next, the mode switching unit 111 determines the time for switching to the operation mode according to the following equation (step S83). If no margin time is provided, zero may be substituted for the margin time AT in the following equation.

Mode switching time = scheduled production start time ST-(set value RTS of recovery time + margin time AT)

The mode switching unit 111 compares the mode switching time with the current time. If the mode switching time is earlier than the current time (step S84; NO), the production start scheduled time ST or the margin time AT is input. Is returned to step S81.

When the mode switching time is determined, the mode switching unit 111 instructs the control unit 112 to switch to the standby mode (step S85). The control unit 112 adjusts the opening of the nitrogen valve to stop or reduce the supply of nitrogen gas, and sets the reflow furnace 100 to a standby state. Thereby, useless energy consumption is suppressed.

Thereafter, the mode switching unit 111 monitors the current time with a timer and waits until the mode switching time is reached (step S86). When the current time reaches the mode switching time, the mode switching unit 111 instructs the control unit 112 to switch to the operation mode (step S87). Thereby, the return process by the control part 112 is started. In parallel with this, a process for updating the set value RTS of the return time by the measuring unit 113 and the updating unit 114 is executed (step S88).

FIG. 9 shows the details of the process for updating the set value RTS of the return time. First, the measurement unit 113 starts a timer and starts measuring an elapsed time from when the operation mode is switched (step S90). And the measurement part 113 monitors the value of the oxygen concentration which is a management item (step S91). When the value of the management item reaches a predetermined management value (4000 ppm) (step S91; YES), the measurement unit 113 adds 1 to the measurement count n (increment) (step S92), and adds a timer value to the measurement value RTn. Is input (step S93), the timer is stopped and cleared (steps S94 and S95).

Subsequently, the updating unit 114 calculates an average value RTAn of n measurement values RT1 to RTn and a standard deviation σn by the following formula (steps S96 and S97).

The standard deviation σn may be obtained by the following formula.

Then, the update unit 114 calculates a new set value RTSn of the return time by the following equation using the average value RTAn and the standard deviation σn obtained in steps S96 and S97 (step S98). X is a constant that can be arbitrarily set, and may be determined according to the process capability (that is, the quality level to be guaranteed in this production facility). In the present embodiment, X = 3 is set.

Finally, the update unit 114 stores the measured value RTn, average value RTAn, standard deviation σn, and set value RTSn obtained in the current update process in the storage unit 110 (step S99). Through the above processing, a new set value RTSn of the return time is determined based on the statistical values RTAn and σn of the actual measurement values RT1 to RTn for a plurality of times.

(Advantages of this embodiment)
The energy saving control of the present embodiment described above has the following advantages. That is, wasteful energy consumption can be suppressed by switching the reflow furnace to the standby mode when the operator is absent due to a break or shift change or when production is temporarily stopped due to setup change or the like. And, since it automatically switches to the operation mode based on the set production start time and return time settings, it is possible to return the reflow furnace to the production ready state by the scheduled production start time and resume production. Become. In addition, since a function to update (learn) the set value using the measured value of the return time is provided, the set value of the return time can be automatically optimized while the reflow furnace is actually operating (that is, online). Can do. Due to differences in operating conditions, installation environment, aging, etc., the same reflow furnace may cause variations in the return time, but by properly updating the set values based on the measured values as in this embodiment, proper return can be achieved. Time can be set automatically.

FIG. 10 shows an example of the mode switching timing when the return time set value RTSn updated (learned) by the method of the present embodiment is used. Compared to FIG. 4, it can be seen that the idling time (T2-T1) from the return to the production-ready state to the resumption of production is greatly shortened, and wasteful energy consumption is further reduced. Further, since the set value RTSn of the return time takes into account the variation of “+ Xσn” obtained from the measured values for n times, in most cases, the state return can be completed by the scheduled production start time T2. it can. In addition, since a margin time (margin for safety) set by the user is also added, even in rare cases such as when the state of the device at the time of mode switching is unusual, the time until the scheduled production start time T2 is reached. It is possible to reliably guarantee the status recovery and the resumption of production.

Furthermore, in this embodiment, the initialization process is executed when the configuration or operating conditions of the reflow furnace are changed, and the return time is learned again from the beginning. Therefore, mode switching based on an invalid setting value is performed. Can be prevented.

(Modification)
In the above-described embodiment, an example in which the supply of nitrogen gas is stopped or reduced in the standby mode has been described. However, similar control is effective even in a configuration in which the supply power to the heater is stopped or reduced in the standby mode. This is because a certain amount of time is required from the state in which the furnace temperature is lowered by stopping or reducing the power supplied to the heater to the return to the temperature at which the production is possible (for example, 230 ° C.). In this case, the determination process in step S91 in FIG. 9 is replaced with a determination process for determining whether the furnace temperature (output of the temperature sensor 22), which is a management item, has reached the control value (230 ° C.). In the standby mode, both supply of nitrogen gas and power supply to the heater may be stopped or reduced. In this case, in step S91 in FIG. 9, it is determined whether both the oxygen concentration and the furnace temperature have reached the control value.

In the above embodiment, it is assumed that the standby mode is started immediately when a command to switch to the standby mode (interrupt) is generated, but it is also preferable to delay the start timing of the standby mode. For example, the mode switching unit 111 switches to the standby mode after a predetermined time (several tens of seconds to several minutes) has elapsed since the occurrence of the interrupt. Assuming an operation in which the user operates the switch at the beginning of a break, etc., there is a possibility that the workpiece remains in the furnace at the time of interrupt occurrence (at the time when the switch operation is performed), so it waits immediately. Switching to mode will produce defective products. Therefore, the mode switching is delayed for a predetermined time to wait for the processing of the work in progress to be completed. The delay time may be set to the same level as the processing time for one workpiece. Alternatively, the presence or absence of a workpiece in the furnace is determined using the detection result of the substrate sensor 21, and when it is confirmed that there is no work in progress after the occurrence of an interrupt, switching to the standby mode is performed. Also good.

Second Embodiment
The second embodiment of the present invention is an example in which the present invention is applied to energy saving control in a clean room. A clean room has a configuration for cleaning the entire room and a configuration for cleaning a local space surrounded by partitions (also called a clean booth), but the present invention can be applied to any configuration. .

FIG. 11 shows the overall configuration of the clean room (clean booth) of the second embodiment. The clean room 400 is a facility for keeping the environment (production environment) around the manufacturing apparatus 401 clean. A transparent sheet (curtain) 403 that forms a manufacturing chamber 402 that is a semi-enclosed space around the manufacturing apparatus 401; A particle sensor 404, a fan filter unit 405, and a controller 406 as a control device are provided.

The lower end of the transparent sheet 403 is separated from the floor by a predetermined height, and an opening 407 is formed at the lower end of the manufacturing chamber 402. A fan filter unit 405 is attached to the upper end (ceiling) of the manufacturing chamber 402. The particle sensor 404 is arranged so as to measure the environment near the pass line of the manufacturing apparatus 401.

The fan filter unit 405 has a blower that takes in air from the outside of the manufacturing chamber 402 and a HEPA filter that removes dust (particles) from the taken-in air. When clean air is supplied from the ceiling of the manufacturing chamber 402 by the fan filter unit 405, the air in the manufacturing chamber 402 flows out from the opening 407. Such ventilation prevents particles from entering the manufacturing chamber 402 and keeps the air in the manufacturing chamber 402 clean.

This clean room 400 can also perform energy saving control by switching between the operation mode and the standby mode, similarly to the reflow furnace of the first embodiment. In the operation mode, the controller 406 controls the power supplied to the fan filter unit 405 according to the output of the particle sensor 404, and adjusts the rotational speed of the blower, that is, the inflow amount of air, thereby cleaning the interior of the manufacturing chamber 402. Keep the degree ready for production. For example, when the cleanliness of the production-ready state is “Class 10,000”, the number of particles having a particle size range of 0.5 μm to 5 μm is maintained at 10,000 or less per cubic foot (1 cf). Is done.

When switched to the standby mode, the controller 406 stops supplying power to the fan filter unit 405 or reduces the supply amount. This reduces energy consumption. However, in the standby mode, the clean air in the manufacturing chamber 402 decreases because the amount of clean air inflow is eliminated or reduced. Therefore, it is necessary to switch to the operation mode before the scheduled production start time and to restore the cleanliness by the scheduled production start time. Therefore, the same control as in the first embodiment and the update process of the set value of the return time can be suitably applied. In this case, the determination process in step S91 in FIG. 9 is replaced with a determination process of whether or not the cleanliness (particle sensor output), which is a management item, has reached a management value (class 10,000).

In the case of the configuration of the second embodiment described above, the same operational effects as those of the first embodiment can be obtained.

<Other embodiments>
The configuration of each embodiment described above is merely a specific example of the present invention, and is not intended to limit the scope of the present invention. The present invention can take various specific configurations without departing from the technical idea thereof. For example, in the above embodiment, the energy saving control of the reflow furnace and the clean room is exemplified, but for production facilities other than these (for example, a manufacturing apparatus, a processing apparatus, a transport apparatus, a storage apparatus, an air conditioner, a lighting apparatus, etc.) Also, the present invention can be applied. In the above-described embodiment, only two operation modes, that is, an operation mode and a standby mode are described, but other operation modes may be provided. Further, in step S83 of FIG. 8, a value obtained by subtracting the sum of the set value RTS and the allowance time AT (RTS + AT) from the scheduled production start time ST is set as the mode switching time. However, the allowance time AT is added in step S99 of FIG. The set value RTS ′ (= RTS + AT) is stored in the storage unit 110, and the same result is obtained even if the mode switching time is calculated by subtracting the set value RTS ′ from the scheduled production start time ST in step S83 of FIG. It is done.

In the above embodiment, the statistical values of all (n times) measurement values RT1 to RTn accumulated in the storage unit 110 are used for the update process, but only the measurement values measured in a predetermined period are extracted. Only a part of the extracted measurement values can be used for the update process. For example, as the production facility deteriorates over time, there may be a change that the return time gradually becomes longer (or shorter). In such a case, it is more appropriate to use only the latest measurement values for the most recent one week or one month for updating the set value RTS than to use all the measurement values accumulated in the storage unit 110. The set value can be obtained. In addition, when the temperature, humidity, or other surrounding environment can affect the return time, the return time may vary depending on the season or time zone. In such a case, for example, it is expected that an appropriate set value RTS can be determined by using the measurement value of the same period last year or using the measurement value of the same time zone.

Claims

A control device for a production facility having an operation mode for maintaining a first state in which production is possible and a standby mode for standby in a second state in which energy consumption is lower than that in the first state,
A storage unit for storing a set value of a return time expected to be required for the production facility to return from the second state to the first state;
When the production facility is in the standby mode, the standby mode is changed from the standby mode to the operation mode based on the time when the production facility should be returned to the first state and the set value of the return time stored in the storage unit. A mode switching unit that determines a switching time to be switched, and switches from the standby mode to the operation mode when the current time reaches the switching time;
A measurement unit that measures a return time actually required until the production facility returns to the first state after being switched to the operation mode by the mode switching unit;
A control device comprising: an update unit configured to update a set value of the return time stored in the storage unit based on a measurement value of the return time measured by the measurement unit.
The control device according to claim 1, wherein the update unit determines a new set value of the return time based on a statistical value of a plurality of measurement values.
Every time measurement by the measurement unit is performed, a measurement value is recorded in the storage unit,
The update unit extracts a plurality of measurement values measured in a predetermined period from all the measurement values recorded in the storage unit, and based on the extracted statistical values of the plurality of measurement values The control device according to claim 2, wherein a new set value of the return time is determined.
The control device further includes an input unit that receives an input of additional time from a user,
When the mode switching unit determines the switching time, or when the updating unit updates the set value of the return time, the input additional time is added to the set value of the return time. The control device according to any one of claims 1 to 3, wherein:
The control device according to any one of claims 1 to 4, further comprising an initialization unit that returns a set value of the return time stored in the storage unit to an initial value.
The control device according to claim 5, wherein the initialization unit returns the set value of the return time to the initial value when the configuration of the production facility or the operation condition is changed.
The production facility is a reflow furnace for heating the solder paste on the substrate,
The operation mode is a mode in which nitrogen gas is supplied into the furnace and the oxygen concentration in the furnace is maintained in the first state.
The control device according to any one of claims 1 to 6, wherein the standby mode is a mode in which the supply of nitrogen gas is stopped or the supply amount is reduced.
The production facility is a reflow furnace for heating the solder paste on the substrate,
The operation mode is a mode in which power is supplied to a heater in the furnace to maintain the temperature in the furnace in the first state,
The control device according to any one of claims 1 to 6, wherein the standby mode is a mode in which power supply to the heater is stopped or a supply amount is reduced.
The production facility is a clean room for keeping the production environment clean,
The operation mode is a mode in which power is supplied to the fan filter unit and the cleanliness in the clean room is maintained in the first state.
The control device according to any one of claims 1 to 6, wherein the standby mode is a mode in which power supply to the fan filter unit is stopped or a supply amount is reduced.