JP7653701B2 - Production management system, operation status detection device, production management device, and production management method - Google Patents

Description

This disclosure relates to a production management system, an operating status detection device, a production management device, and a production management method.

There is a known production management system that detects a pulse signal output from production equipment each time a part is dispensed, and measures the cycle time from the high position of the pulse signal to the high position of the next pulse signal (for example, see Patent Document 1). In the production management system, the cycle time is determined to be over when the time from detecting the high position of the pulse signal to detecting the high position of the next pulse signal exceeds a certain time.

Japanese Unexamined Patent Publication No. 8-185204

Conventional technology has the problem that it is not possible to detect an abnormality in the cycle time from when one pulse signal is detected until the next pulse signal is detected. This problem becomes more pronounced in production equipment that produces products with long cycle times.

This disclosure can be realized in the following forms:

(1) According to one embodiment of the present disclosure, there is provided a production management system. The production management system includes an operation status detection device that generates a first signal corresponding to a start of a process by production equipment and generates a second signal corresponding to a completion of the process, and a production management device that acquires the first signal and the second signal and acquires an acquisition interval between successive first signals as a cycle time. The production management device determines an abnormality in the cycle time using the first signal and the second signal.
According to this embodiment of the production management system, by using the first signal and the second signal to determine whether or not there is an abnormality in the cycle time, it is possible to determine whether or not there is an abnormality in the cycle time at the time the second signal is acquired. Therefore, it is possible to detect an abnormality in the cycle time at an earlier stage than in a system in which the abnormality in the cycle time is determined using only the first signal.
(2) In the production management system of the above embodiment, the production management device may acquire a processing period from the time when the first signal is acquired to the time when the second signal is acquired, and may determine that there is an abnormality in the cycle time if the processing period differs from a predetermined reference period.
According to this embodiment of the production management system, the production management device determines that there is an abnormality in the cycle time when the processing period differs from a predetermined reference period. Therefore, the production management device can detect an abnormality in the cycle time before acquiring the cycle time by determining the abnormality using the processing period.
(3) In the production management system of the above aspect, the production management device may determine that there is an abnormality in the cycle time when it determines that the processing period is longer than the predetermined reference period.
According to the production management system of this embodiment, an abnormality in the cycle time can be detected at the time the second signal is detected.
(4) In the production management system of the above aspect, the production management device may determine that there is an abnormality in the cycle time if the second signal is not acquired when the predetermined reference period has elapsed from the time when the first signal is detected.
According to the production management system of this aspect, it is possible to determine whether there is an abnormality in the cycle time without waiting for the detection of the second signal, and therefore it is possible to detect the abnormality in the cycle time at an earlier stage.
(5) In the production management system of the above aspect, the operation status detection device may include a first transmission unit for outputting the first signal to the production management device, and a second transmission unit for outputting the second signal to the production management device.
According to this embodiment of the production management system, the first and second detection signals can be transmitted by the first and second transmission units, and the production management device can easily distinguish between the start and end of processing by the production equipment.
(6) In the production management system of the above aspect, the operation state detection device may be attached to the production equipment or may be disposed near the production equipment.
According to this type of production management system, the production status and cycle time of existing manufacturing facilities can be managed by a simple device.
(7) According to another aspect of the present disclosure, there is provided an operation status detection device for use in a production facility, the operation status detection device detecting that the production facility has started a process and generating a first signal, and detecting that the production facility has stopped the process and generating a second signal.
According to the operational status detection device of this embodiment, a detection signal for detecting a processing period or cycle time in an existing manufacturing facility can be obtained by a simple device.
(8) According to another aspect of the present disclosure, there is provided a production management device for managing an operating state of a production facility. The production management device detects a first signal generated when the production facility starts a process and a second signal generated when the production facility stops a process. If a processing period, which is a period from when the first signal is detected to when the second signal is detected, differs from a predetermined reference period, it is determined that there is an abnormality in the cycle time of the production facility.
According to this form of production management device, the processing period and cycle time in existing manufacturing facilities can be managed by a simple device.
The present disclosure can also be realized in various forms other than a production management system, an operation status detection device, and a production management device, for example, a production management method, a manufacturing line or production equipment, a control method for a production management system, a control method for an operation status detection device, a control method for a production management device, a computer program for implementing the control method, a non-transitory recording medium on which the computer program is recorded, etc.

1 is a schematic configuration diagram showing a production management system according to a first embodiment of the present disclosure. FIG. 2 is a block diagram showing the internal functional configuration of the production management device according to the first embodiment. FIG. 2 is a block diagram showing the internal functional configuration of the operating state detection device according to the first embodiment. FIG. 2 is an explanatory diagram showing an example of the arrangement of an operating state detection device having an optical sensor as a detection unit. FIG. 13 is an explanatory diagram of a case in which the operation status detection device is disposed in the vicinity of production equipment. FIG. 13 is an explanatory diagram of a case in which the operation status detection device is attached to production equipment and used. 4 is a flowchart showing a process executed by the operation status detection device of the first embodiment. 4 is a flowchart showing a process executed by the production management device in the first embodiment. FIG. 4 is an explanatory diagram showing an example of production status information displayed on the display device. FIG. 4 is an explanatory diagram showing an example of a detailed display displayed on a display device. 10 is a flowchart showing a process executed by a production management device in a second embodiment.

A. First embodiment:
1 is a schematic configuration diagram showing a production management system 100 according to a first embodiment of the present disclosure. The production management system 100 includes a production management device 10 and operation status detection devices 20a to 20f. The production management device 10 cooperates with the operation status detection devices 20a to 20f to manage the production status of a first production line L1 and a second production line L2. The number of production lines is not limited to two, and may be one, or three or more.

The manufacturing lines L1 and L2 are equipped with production equipment 31-36 and a conveying mechanism 41. The conveying mechanism 41 conveys items to be processed, such as processed parts and workpieces. The conveying mechanism 41 includes, for example, a belt conveyor and a conveying machine that moves on a predetermined track. The production equipment 31-36 is arranged on the conveying mechanism 41.

The production equipment 31-36 is, for example, equipment such as metal processing machines, welding machines, resin molding machines, painting machines, hot forging machines, finished product recovery machines, and processed part supply machines. The production equipment 31-36 is equipped with a programmable logic controller (PLC) for executing production and processing processes on the workpieces, and various sensors connected to the PLC, such as photoelectric sensors and area sensors. The various sensors are arranged in advance when the production lines L1, L2 and the production equipment 31-36 are installed and positioned in order to operate the production lines L1, L2 and the production equipment 31-36.

As shown in FIG. 1, the first production line L1 is provided with a first production facility 31, a second production facility 32, and a third production facility 33. The second production line L2 is provided with a fourth production facility 34, a fifth production facility 35, and a sixth production facility 36.

The operating status detection devices 20a to 20f are attached to the production equipment 31 to 36 by retrofitting, or are arranged in the vicinity of the production equipment 31 to 36 by retrofitting. In this disclosure, retrofitting means that they are not attached or incorporated in the production equipment when the production equipment is installed and arranged, are not connected to the PLC that controls the operation of the production equipment, and are attached and arranged in the production equipment regardless of the operation and control of the production equipment. In the example of FIG. 1, the first operating status detection device 20a is attached to the first production equipment 31, the second operating status detection device 20b is attached to the second production equipment 32, and the fourth operating status detection device 20d is attached to the fourth production equipment 34. The fifth operating status detection device 20e is attached to the discharge side of the fifth production equipment 35, and the third operating status detection device 20c and the sixth operating status detection device 20f are arranged in the vicinity of the downstream side of the third production equipment 33 and the sixth production equipment 36 in the conveying direction, respectively.

As shown in FIG. 1, the production management device 10 and the operation status detection devices 20a to 20f can transmit and receive data to each other by wireless communication. For example, the production management device 10 transmits the generated production status information to the terminal devices PD1 and PD2 by wireless communication in response to a request from the terminal devices PD1 and PD2. The production status information means information related to the operation status of the production equipment. The production status information includes, for example, the operation time of the production equipment, the production number, the output per unit time, the operation rate (%), the cycle time, the processing period, the stop period, and the delay period. The operation time means the cumulative time during which the production equipment is operating after the start of the production equipment. The production number means the total number of processed items produced by the production equipment. The output per unit time means, for example, the number of processed items processed per hour. The operation rate means the ratio of the production number to the planned number. The production management device 10 may be arranged in a factory as a local server, or may be arranged in a place other than the factory as a remote server. When the production management device 10 is installed as a remote server, the detection signals from the retrofitted operating status detection devices 20a-20f and the production status information to the terminal devices PD1, PD2 and the local computer are transmitted and received by the production management device 10 via wireless access points in the factory and a network such as an intranet or the Internet. The detection signals from the operating status detection devices 20a-20f include a first signal corresponding to the start of processing the workpiece by the production equipment 31-36 and a second signal corresponding to the completion of processing the workpiece by the production equipment 31-36.

Figure 2 is a block diagram showing the internal functional configuration of the production management device 10 in the first embodiment. The production management device 10 is equipped with a CPU 11, which is a central processing unit, a storage device 12, a transmission/reception unit 13, a display device 14, an input device 15, and a timer 16 for measuring time, which are connected to each other via a bus 17 so that they can communicate with each other. The CPU 11, the storage device 12, and the transmission/reception unit 13 can communicate with each other bidirectionally. The production management device 10 is a device different from the PLC that controls the operation of the production equipment 31-36, and the operation of the production equipment 31-36 is controlled by the PLC even if the production management device 10 is not used.

The CPU 11 functions as a cycle time generating unit 111 and a production status information generating unit 113 by executing various programs stored in the storage device 12. The storage device 12 is, for example, a RAM, a ROM, or a hard disk drive (HDD). Various programs for implementing the functions provided in this embodiment are stored in the HDD or ROM. Various programs read from the HDD or ROM are expanded on the RAM and executed by the CPU 11. The readable and writable area of the storage device 12 is provided with a cycle time storage unit 121 that stores the generated cycle time (CT), and a production status information storage unit 123 that stores the generated production status information. The storage device 12 temporarily stores the first and second signals received from the operation status detection devices 20a to 20f.

The transmitting and receiving unit 13 receives a first signal and a second signal via wireless communication from the operation status detection devices 20a to 20f that are attached to the production equipment 31 to 36 on the manufacturing lines L1 and L2 or that are located near the production equipment 31 to 36. The transmitting and receiving unit 13 transmits various execution commands to the operation status detection devices 20a to 20f. The transmitting and receiving unit 13 may further transmit production status information to the terminal devices PD1 and PD2, and may receive command signals from the terminal devices PD1 and PD2 that request the execution of various processes.

The transmitting and receiving unit 13 can acquire the first and second signals from the operating state detection devices 20a to 20f without being connected to the operating state detection devices 20a to 20f by wire. By configuring in this way, the production management system 100 of this embodiment can be introduced into an existing factory by using a simple method of retrofitting or arranging the operating state detection devices 20a to 20f to the production equipment 31 to 36. For example, if the transmitting and receiving unit 13 is an input/output I/F having a wireless communication function, the transmitting and receiving unit 13 may receive wireless radio waves from the operating state detection devices 20a to 20f through a wireless repeater (access point) (not shown) installed in the factory, or the transmitting and receiving unit 13 itself may be placed in a place where it can receive wireless radio waves from the operating state detection devices 20a to 20f as a wireless access point. The transmitting and receiving unit 13 may also be connected to the wireless repeater by wire. Wireless communication can be achieved, for example, by a wireless connection through a wireless local network (LAN) that complies with the IEEE 802.11 standard or wireless communication using Bluetooth (registered trademark).

The display device 14 is a display for displaying the process contents, cycle time, and production status information when operating the production management system 100. The display device 14 may be provided separately from the production management device 10. For example, if the production management device 10 is a remote server and is provided to generate production status information, the display device 14 may not be provided. The input device 15 is a device used to input to the production management system 100. The input device 15 is, for example, a keyboard or a mouse. The input device 15 may be a touch panel provided on the screen of the display device 14.

Figure 3 is a block diagram showing the functional configuration of the operating status detection devices 20a to 20f in the first embodiment. In Figure 3, the first operating status detection device 20a is used as an example for explanation, but the second operating status detection device 20b to the sixth operating status detection device 20f have the same configuration. The operating status detection devices 20a to 20f are attached or placed on the manufacturing lines L1, L2 or production equipment as an add-on. The first operating status detection device 20a includes a detection unit 25a, a first transmission/reception unit 21a, a second transmission/reception unit 22a, and a controller 23a. The detection unit 25a, the first transmission/reception unit 21a, and the second transmission/reception unit 22a are connected to the controller 23a so as to be able to communicate with each other.

The detection unit 25a is a variety of sensors that are attached to the production equipment 31-36 or placed near the production equipment 31-36. The detection unit 25a is a sensor that is different from existing sensors connected to a programmable logic controller (PLC). The detection unit 25a may be provided integrally with the first operating status detection device 20a, or may be separate from the first operating status detection device 20a. When the detection unit 25a is separate from the first operating status detection device 20a, it is connected to the first operating status detection device 20a via a signal line. The detection unit 25a may be a detection unit that has only a detection element and outputs an analog signal, or may be a detection unit that has a detection element and a circuit that converts the signal output from the detection element into a digital signal and outputs it.

Sensors used as the detection unit 25a include light sensors, sound sensors, heat sensors, current sensors, distance sensors, air pressure sensors, acceleration sensors, rotational speed sensors, humidity sensors, and pressure sensors. Each sensor is used to detect the operating state of the production equipment. In this embodiment, the operating state refers to the start and stop of processing of the workpieces on the manufacturing line and in the production equipment. The operating state may also include other states such as processing, operations and manipulations related to processing, and the start, execution, stop, and completion of the operations and manipulations.

The detection unit 25a detects the start of processing of the workpiece by the production equipment 31 and the completion of processing of the workpiece by the production equipment 31, and generates a pulse signal. The generated pulse signal is output to the controller 23a. The detection unit 25a is a single detection unit, and generates a pulse signal that rises (ON) from a reference state when it detects the start of processing by the production equipment 31, and falls (OFF) from an ON state when it detects the completion of processing by the production equipment 31. The detection unit 25a may generate a pulse signal that falls (OFF) from an ON state to a reference state when it detects the start of processing by the production equipment 31, and rises (ON) from a reference state when it detects the completion of processing by the production equipment 31. The detection unit 25a may also be two detection units, one that generates a pulse signal corresponding to the start of processing by the production equipment 31 and the other that generates a pulse signal corresponding to the completion of processing by the production equipment 31.

The controller 23a includes a central processing unit (CPU) and a storage device (not shown). The controller 23a generates a first signal and a second signal with an identifier identifiable by the production management device 10 using the pulse signal received from the detection unit 25a, and outputs the first signal and the second signal to the first transmission/reception unit 21a and the second transmission/reception unit 22a, respectively. Specifically, the controller 23a detects the rising edge (ON) of the pulse signal received from the detection unit 25a, generates a first signal and outputs it to the first transmission/reception unit 21a, and when it detects the falling edge (OFF) of the pulse signal received from the detection unit 25a, generates a second signal and outputs it to the second transmission/reception unit 22a. The detection unit 25a may generate the first signal and the second signal and output them to the controller 23a. When the signal input from the detection unit 25a is an analog signal, the controller 23a converts the signal into a digital signal that is High (1) in active-high logic and Low (1) in active-low logic when the signal value is equal to or greater than a preset value, less than a preset value, or within an arbitrary range, and transmits the first and second signals to the production management device 10. In the present embodiment, an example has been shown in which only the detection unit 25a functions as the detection unit, but the detection unit may be realized by the detection unit 25a and the controller 23a. The controller 23a may store the pulse signal received from the detection unit 25a in a storage device, and execute a process of transmitting the first and second signals to the production management device 10 in response to an execution command received from the production management device 10.

The first transceiver 21a and the second transceiver 22a transmit a first signal and a second signal to the production management device 10 by wireless communication according to an arbitrary communication protocol. More specifically, the first transceiver 21a functions as a first transmitter that transmits a first signal to the production management device 10, and the second transceiver 22a functions as a second transmitter that transmits a second signal to the production management device 10. The first transceiver 21a and the second transceiver 22a may generate the first signal and the second signal according to a command from the controller 23a that receives a pulse signal from the detector 25a. The first transceiver 21a and the second transceiver 22a may also receive an execution command from the production management device 10.

Figure 4 is an explanatory diagram showing an example of the arrangement of an operating status detection device 20b equipped with an optical sensor as the detection unit 25b. As shown in Figure 1, the second operating status detection device 20b is provided in the second production facility 32. More specifically, a housing 32b that houses a PLC is arranged adjacent to the second production facility 32. The housing 32b is equipped with a signal tower 40 that indicates the operating status of the second production facility 32 with three colored signal lights. The operating status indicated by the signal tower 40 is, for example, green for processing, yellow for processing complete, and red for abnormal stop.

As the optical sensor of the detection unit 25b, a photoelectric conversion element capable of detecting the lighting or extinction of the signal light, such as a photodiode or a phototransistor, can be used. The detection unit 25b is attached, for example, to the light-emitting surface of a green signal light. By attaching the second operating state detection device 20b to the signal tower 40, it is possible to easily detect the start or completion of processing of the workpiece by the second production equipment 32 indicated by the signal tower 40. Specifically, when the green signal light is lit, the detection unit 25b detects the start of processing by the production equipment 32, and when the green signal light is extinguished, the detection unit 25b detects the completion of processing by the production equipment 32. When the controller 23b detects the start of processing by the production equipment 32 using the pulse waveform from the detection unit 25b, it generates a first signal and outputs it to the first transmission/reception unit 21b, and when the controller 23b detects the completion of processing by the production equipment 32 using the pulse waveform from the detection unit 25b, it generates a second signal and outputs it to the second transmission/reception unit 22b. The detector 25b may generate a first signal and a second signal and output them to the controller 23b. The detector 25b may output a current corresponding to the amount of light received to the controller 23b. In this case, when the amount of light received is equal to or greater than a predetermined amount, a pulse waveform is generated as the first signal by the controller 23b, and when the amount of light received is less than the predetermined amount, a pulse waveform is generated as the second signal by the controller 23b.

Figure 5 is an explanatory diagram of a case where an operating status detection device is placed near a production facility and used. As shown in Figure 5, the third operating status detection device 20c is placed near the third production facility 33. The third operating status detection device 20c has two detection units 25c1 and 25c2. The detection units 25c1 and 25c2 are provided in positions different from the main body of the third operating status detection device 20c that houses the transceiver unit 22c and the controller 23c, and are connected to the third operating status detection device 20c by a signal line.

Detection units 25c1 and 25c2 are disposed at the upper end of the support unit that supports the transport mechanism 41. Detection unit 25c1 is disposed near the input position of the workpiece WP to the third production facility 33, and detection unit 25c2 is disposed near the discharge position of the workpiece WP from the third production facility 33.

For example, photoelectric optical sensors can be used as the detection units 25c1 and 25c2. With a photoelectric optical sensor, the passage of the workpiece WP transported by the transport mechanism 41 can be detected by blocking light. The first and second signals output when the light is blocked are pulse signals of 1 or 0. The photoelectric sensor is composed of a light source that outputs light such as visible light, infrared light, and ultraviolet light, and a light receiving unit that receives the light from the light source. By disposing the retrofit third operating state detection device 20c in the vicinity of the third production facility 33, the start and completion of processing by the third production facility 33 can be detected using the presence or absence of the transport of the workpiece WP. Specifically, the detection unit 25c1 of the third operating state detection device 20c detects the input of the workpiece WP to the third production facility 33 to detect the start of processing by the third production facility 33, and the detection unit 25c2 detects the discharge of the workpiece WP from the third production facility 33 to detect the completion of processing by the third production facility 33. When the controller 23c detects the start of processing by the production equipment 33 using the pulse waveform from the detector 25c1, it generates a first signal and outputs it to the first transmitter/receiver 21c, and when it detects the completion of processing by the production equipment 33 using the pulse waveform from the detector 25c2, it generates a second signal and outputs it to the second transmitter/receiver 22c. The generated first and second signals are provided to the production management device 10 by the first transmitter/receiver 21c and the second transmitter/receiver 22c.

Figure 6 is an explanatory diagram of a case where the operating status detection device is attached to a production facility and used. As shown in Figure 6, the fifth operating status detection device 20e is attached to a position near the discharge outlet of the workpiece WP in the fifth production facility 35. The detection units 25e1 and 25e2 are provided in a different position from the main body of the fifth operating status detection device 20e that houses the transceiver unit 22e and the controller 23e, and are connected to the fifth operating status detection device 20e by a signal line.

Detection unit 25e1 is provided at the inlet of the workpiece WP in the fifth production facility 35, and detection unit 25e2 is provided near the outlet of the workpiece WP in the fifth production facility 35. For example, a light sensor, a sound sensor, a heat sensor, a current sensor, a distance sensor, an air pressure sensor, an acceleration sensor, a rotational speed sensor, a humidity sensor, and a pressure sensor are used as detection units 25e1 and 25e2. In this embodiment, detection unit 25e1 detects the start of processing of the workpiece WP in the fifth production facility 35, and detection unit 25e2 detects the completion of processing of the workpiece WP in the fifth production facility 35.

The operation of the operating state detection device 20a will be described using FIG. 7. FIG. 7 is a flowchart showing the processing executed by the operating state detection device 20a of the first embodiment. This flow can be executed repeatedly from the start-up of the operating state detection device 20a until the operation of the operating state detection device 20a is terminated. Note that similar processing can also be executed in the other operating state detection devices 20b to 20f.

In step S200, the operating state detection device 20a checks whether a pulse signal has been input from the detection unit 25a. If a pulse signal has not been input from the detection unit 25a (S200: NO), the controller 23a waits for the input of a pulse signal.

When the controller 23a receives a pulse signal from the detector 25a (step S200: Yes), it detects the rising edge (on) or falling edge (off) of the detected pulse signal (step S210). When the controller 23a detects the rising edge (on) of the pulse signal (S210: YES), it generates a first signal indicating the start of processing the workpiece by the production equipment 31 and outputs it to the first transmitter/receiver 21a, and the first transmitter/receiver 21a transmits the acquired first signal to the production management device 10 (step S211). When the controller 23a detects the falling edge (off) of the pulse signal (S210: NO), it outputs a second signal corresponding to the completion of processing the workpiece by the production equipment to the second transmitter/receiver 22a, and the second transmitter/receiver 22a transmits the acquired second signal to the production management device 10 (step S212).

The operation of the production management device 10 will be described with reference to FIG. 8. FIG. 8 is a flowchart showing the processing executed by the production management device 10 of the first embodiment. This flow is started, for example, by starting up the production management device 10. Upon starting up, the production management device 10 waits to receive a detection signal. The production management device 10 receives a first signal corresponding to the start of processing by the production equipment 31 from the operation status detection device 20a via wireless communication at the transmission/reception unit 13 (step S10). The received first signal is stored in the storage device 12. The production management device 10 starts timing from the point in time when the first signal is received (step S20).

The production management device 10 receives a second signal corresponding to the completion of processing by the production equipment 31 from the operation status detection device 20a via wireless communication at the transmitter/receiver unit 13 (step S30). The received second signal is stored in the memory device 12. The production management device 10 completes timing at the time of receiving the second signal and acquires the processing period (step S40). The processing period is the period from the time the first signal is received to the time the second signal is received. The processing period corresponds to the period from the time the processed item is input to the production equipment to the time the processed item is discharged, i.e., the period during which the production equipment is performing processing such as processing of the processed item.

The production management device 10 checks whether the acquired processing period is within a predetermined reference period (step S50). The predetermined reference period is a threshold value for determining whether there is an abnormality in the processing period. The reference period can be set arbitrarily using, for example, the average processing period of the production equipment or the shortest processing period. If the processing period is within the reference period (S50: YES), the production management device 10 determines that there is no abnormality in the cycle time and stores the determination result in the storage device 12. If the processing period is longer than the reference period (S50: NO), the production management device 10 determines that there is an abnormality in the cycle time and stores the determination result in the storage device 12.

When the production management device 10 judges that the cycle time is abnormal, it waits until it detects a new first signal (step S60). When it detects a first signal (S60: YES), it starts timing to measure the cycle time for processing the next workpiece WP (step S70). In step S80, the production management device 10 calculates the cycle time. Specifically, the CPU 11 executes a program to function as the cycle time generation unit 111. The cycle time generation unit 111 acquires the period from the detection of the first signal in step S10 to the detection of the next first signal, i.e., the detection of the first signal in step S60, as the cycle time. When a new first signal is detected in step S60, the cycle time is the period from the detection of the first signal in step S60 to the detection of the next first signal in step S60 again. The acquired cycle time is stored in the cycle time storage unit 121.

In step S90, the production management device 10 generates production status information using the acquired detection signal, as described below. Specifically, the CPU 11 executes a program to function as the production status information generation unit 113. The generated production status information is stored in the production status information storage unit 123. In step S100, the production management device 10 causes the display device 14 to display the cycle time and the production status information, and transitions to step S30.

If the first signal cannot be detected within the specified period in step S60 (S60: NO), it is confirmed whether or not to end the process (step S110). If the process is not to be ended (S110: NO), the process returns to step S10. If the process is to be ended (S110: YES), the production management device 10 ends this flow.

Figure 9 is an explanatory diagram showing an example of production status information displayed on the display device 14. In the example of Figure 9, the time T0 when the first signal was first input after the production line was started, the production efficiency (%) of the production lines L1 and L2, and the number of times that abnormalities in the cycle time (CT) of each of the production equipment 31-36 arranged on the production lines L1 and L2 have occurred are displayed. In this embodiment, a detail display button B1 is provided for displaying more detailed information about the cycle time abnormality item. Note that this information may be displayed on the display units of the terminal devices PD1 and PD2 instead of the display device 14 provided in the production management device 10.

When the detail display button B1 is operated, the screen of the display device 14 changes and details of the cycle time are displayed. FIG. 10 is an explanatory diagram showing an example of a detailed display of the cycle time displayed on the display device 14. As shown in FIG. 10, in the detailed display after the detail display button B1 is operated, the cycle time (CT) and the breakdown of the cycle time, specifically the processing period and downtime, are displayed in the order of reception for a predetermined number of times (10 times in the illustrated example). A downtime is a period during which the production equipment is not processing the workpiece. A downtime period includes, for example, a so-called changeover period and a period during which preparations are being made to start processing the next workpiece.

In this embodiment, the production management device 10 judges that a cycle time abnormality (CT abnormality) occurs when the processing period exceeds a predetermined reference period (20 seconds in the example of FIG. 10). When the production management device 10 judges that a cycle time abnormality occurs, it displays the period delayed from the processing period as the delay period as shown as the delay period in FIG. 10, and displays the delay period on the display device 14 with the display "CT abnormality" to notify the operator of the production equipment or the manager of the production management system 100. Instead of or in addition to the display device 14, the notification may be made via the display unit of the terminal devices PD1 and PD2, the display device of the production equipment, an andon, etc. According to the production management device 10 and the operation status detection devices 20a to 20f in this embodiment, it is possible to grasp in detail the presence or absence of cycle time abnormalities in each of the production lines L1 and L2 and the production equipment 31 to 36, which can contribute to clarifying the cause of low operation rates.

As described above, the production management system 100 of this embodiment includes operation status detection devices 20a-20f that generate a first signal corresponding to the start of processing by the production equipment 31-36 and a second signal corresponding to the completion of processing, and a production management device 10 that acquires the acquisition period of consecutive first signals as a cycle time. By using the first and second signals to determine an abnormality in the cycle time, the production management device 10 can determine an abnormality in the processing period at the time when the second signal is acquired, i.e., when the processing period is acquired, and determine whether or not there is an abnormality in the cycle time. Therefore, it is possible to detect an abnormality in the cycle time earlier than in a form in which an abnormality in the cycle time is determined using only the first signal.

According to the production management system 100 of this embodiment, the production management device 10 determines that there is an abnormality in the cycle time when the processing period differs from a predetermined reference period. Therefore, the production management device 10 can detect an abnormality in the cycle time before acquiring the cycle time by determining the abnormality using the processing period.

According to the production management system 100 of this embodiment, the production management device 10 determines that there is an abnormality in the cycle time when it determines that the processing period is longer than a predetermined reference period. Therefore, by determining whether there is an abnormality in the cycle time when the processing period is acquired, it is possible to detect an abnormality in the cycle time when the second signal is detected, without waiting for the detection of the next first signal.

According to the production management system 100 of this embodiment, the operating status detection devices 20a to 20f are equipped with a first transmission unit for outputting a first signal to the production management device 10, and a second transmission unit for outputting a second signal to the production management device 10. Detection signals different from the first signal and the second signal can be transmitted by the two transmission/reception units, the first transmission/reception unit and the second transmission/reception unit. Therefore, the production management device 10 can easily distinguish between the start and completion of processing of the production equipment 31 to 36.

According to the production management system 100 of this embodiment, the operating status detection devices 20a to 20f are attached to the production equipment 31 to 36 or are placed near the production equipment 31 to 36. Therefore, the production status and cycle time of the existing manufacturing lines L1 and L2 can be managed by a simple device.

B. Second embodiment:
Fig. 11 is a flowchart showing the process executed by the production management device 10 of the second embodiment. As shown in Fig. 11, this embodiment differs from the production management system 100 of the first embodiment in that, from the viewpoint of detecting an abnormality in the cycle time earlier, an abnormality in the cycle time is detected before the second signal is received. Specifically, this flow differs from the process in the first embodiment in that steps S50 to S54 are not provided between steps S40 and S60, and steps S56 to S59 are provided between steps S20 and S30. The other points are the same as those in the process in the first embodiment.

As shown in FIG. 11, when the first signal is detected and timing is started in steps S10 to S20, the production management device 10 determines in step S56 whether the elapsed time from the start of timing exceeds a predetermined reference time. If the elapsed time does not exceed the reference time (S56: YES), it is determined that there is no abnormality in the cycle time and waits for detection of the second signal (step S59). If the second signal is not detected (S59: NO), the process returns to step S56. If the second signal is detected (S59: YES), the process proceeds to step S30. If the elapsed time exceeds the reference time in step S56 (S56: NO), it is determined that there is an abnormality in the cycle time at that time (step S58), and the process proceeds to step S30 and waits for detection of the second signal.

According to the production management system 100 of this embodiment, if the second signal is not acquired when the elapsed time from the time when the first signal is detected exceeds a predetermined reference period, the production management device 10 determines that there is an abnormality in the cycle time. Therefore, it is possible to determine an abnormality in the cycle time without waiting for the detection of the second signal, and it is possible to detect an abnormality in the cycle time at an earlier stage.

C. Other embodiments:
(C1) In the first embodiment, three pieces of production equipment 31 to 36 are arranged on each of the production lines L1 and L2, but the number of pieces of production equipment may be one or two for each of the production lines L1 and L2, or four or more. The number of production lines may be one or two, or three or more.

(C2) In the first embodiment, the production management device 10 and each of the operation state detection devices 20a to 20f communicate by wireless communication, but wired communication may also be used. For example, if a wired local area network (LAN) connection port is provided near the production equipment 31 to 36, the connection port can be used to eliminate the need for new wiring, and the production management system 100 according to the first embodiment can be easily introduced in the same way as wireless communication.

(C3) In the above first embodiment, examples were given in which a light sensor, a sound sensor, a heat sensor, a current sensor, a distance sensor, an air pressure sensor, an acceleration sensor, a rotational speed sensor, a humidity sensor, and a pressure sensor were used as sensors used as the detection unit 25a. In contrast, a magnetic sensor may be used as the detection unit. The detection unit as a magnetic sensor can be attached, for example, to an opening and closing door provided in the production equipment. The opening and closing door opens, for example, when the processing of the workpiece by the production equipment starts and when the processing by the production equipment ends. The detection unit can detect the opening and closing of the opening and closing door using a change in magnetic force caused by a change in the distance between the magnetic sensor and a magnet attached to the production equipment, and can detect the start and completion of processing of the workpiece from the opening and closing of the opening and closing door.

The control unit and the method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control unit and the method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and the method described in the present disclosure may be realized by one or more dedicated computers configured by combining a processor and a memory programmed to execute one or more functions with a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transient tangible recording medium as instructions executed by the computer.

The present disclosure is not limited to the above-described embodiments, and can be realized in various configurations without departing from the spirit of the present disclosure. For example, the technical features of the embodiments corresponding to the technical features in each form described in the Summary of the Invention column can be replaced or combined as appropriate to solve some or all of the above-described problems or to achieve some or all of the above-described effects. Furthermore, if a technical feature is not described as essential in this specification, it can be deleted as appropriate.

10...production management device, 11...CPU, 12...storage device, 13...transmission/reception unit, 14...display device, 15...input device, 16...timer, 17...bus, 20a-20f...operation status detection device, 21a-21c...first transmission/reception unit, 22a-22e...second transmission/reception unit, 23a-23e...controller, 25a, 25b, 25c1, 25c2, 25e1, 25e2...detection unit, 31-36...production equipment, 32b...casing, 40...signal tower, 41...transport mechanism, 100...production management system, 111...cycle time generation unit, 113...production status information generation unit, 121...cycle time storage unit, 123...production status information storage unit, B1...detailed display button, L1, L2...production line, PD1, PD2...terminal device, T0...time, WP...processed item

Claims (9)

A production management system,
an operating status detection device that generates a first signal corresponding to the start of a process by the production equipment and generates a second signal corresponding to the completion of the process;
a production management device that acquires the first signal and the second signal, and acquires an acquisition interval of successive first signals as a cycle time;
the production management device determines an abnormality in the cycle time by using the first signal and the second signal.
Production management system. The production management system according to claim 1,
The production management device includes:
A period from when the first signal is acquired to when the second signal is acquired is acquired as a processing period;
When the processing period is different from a predetermined reference period, it is determined that there is an abnormality in the cycle time.
Production management system. The production management system according to claim 2,
the production management device determines that there is an abnormality in the cycle time when it determines that the processing period is longer than the predetermined reference period.
Production management system. The production management system according to claim 2,
When the second signal is not acquired when the predetermined reference period has elapsed since the first signal was detected, the production management device determines that there is an abnormality in the cycle time.
Production management system. The production management system according to any one of claims 1 to 4,
the operation status detection device includes a first transmission unit for outputting the first signal to the production management device, and a second transmission unit for outputting the second signal to the production management device;
Production management system. The production management system according to any one of claims 1 to 5,
The operation state detection device is attached to the production equipment or disposed near the production equipment.
Production management system. An operating status detection device for use in a production facility, comprising:
generating a first signal upon detecting that the production facility has started processing, and generating a second signal upon detecting that the production facility has stopped processing;
Operational status detection device. A production management device for managing an operating state of a production facility,
Detecting a first signal generated when the production facility starts a process and a second signal generated when the production facility stops a process;
When a processing period, which is a period from when the first signal is detected to when the second signal is detected, is different from a predetermined reference period, it is determined that there is an abnormality in the cycle time of the production equipment.
Production control device. A production management method for managing a production status of a production facility, comprising the steps of:
obtaining, from a detection device attached to the production equipment or disposed near the production equipment, a first signal corresponding to the start of a process by the production equipment and a second signal corresponding to the completion of the process;
using the first signal and the second signal, determining an abnormality in a cycle time, which is an interval between successive acquisitions of the first signal;
Production management methods.

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