JP2012238055A - Control method of production apparatus, program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively reduce the power consumption while ensuring the stability of production.SOLUTION: A control unit determines whether an upstream buffer number Nu is equal to or larger than a third threshold value Tu2 and a downstream buffer number Nl is equal to or smaller than a fourth threshold value Tl2 (S17). When it is determined that the upstream buffer number Nu is equal to or larger than the third threshold value Tu2 and the downstream buffer number Nl is not equal to or smaller than the fourth threshold value Tl2, the control unit determines whether the upstream buffer number Nu is equal to or smaller than a first threshold value Tu1 or the downstream buffer number Nl is equal to or larger than a second threshold value Tl1 (S18). When it is determined that the upstream buffer number Nu is equal to or smaller than the first threshold value Tu1, or the downstream buffer number Nl is equal to or larger than the second threshold value Tl1, the control unit executes a power consumption reducing control (S19). When it is determined that the upstream buffer number Nu is equal to or larger than the third threshold value Tu2 and the downstream buffer number Nl is equal to or smaller than the fourth threshold value Tl2, the control unit stops the power consumption reducing control (S21).

Description

  The present invention relates to a control method, a program, and a recording medium for a production apparatus that performs one process of a production line.

  In general, in an automatic production line, a series of operations for production are divided into processes each having the same operation time, and are allocated to different production apparatuses. Although the design is performed by an engineer, it is difficult in practice to make the operating time of each production device the same because of restrictions on the structure of the product and the manufacturing process, and there is a difference in the operating time of each production device.

  Therefore, a production device with a short operation time is in a standby state until the operation of another production device with a long operation time is completed, and does not contribute to production but consumes power wastefully. Become. In addition, each production apparatus may be abnormal due to variations in parts due to lot changes. It is rare for a production device in which an abnormality has occurred to recover automatically, and in most cases, the operator performs a recovery process. At this time, until the operator completes the recovery process or shuts off the power supply, each production apparatus is in a standby state, and is in a state of consuming power wastefully.

  Therefore, conventionally, a method has been proposed in which it is determined whether or not the production apparatus is in a standby state, and in the standby state, power consumption is reduced by means such as cutting off the power supply of each work unit of the production apparatus (Patent Document 1). reference). The determination as to whether or not the production apparatus is in a standby state is made mainly from information on whether the upstream production apparatus can carry out the next workpiece and information on whether or not the downstream production apparatus can carry in the next workpiece. That is, information exchange with upstream and downstream production apparatuses is only a carry-in preparation completion signal and a carry-out preparation completion signal.

Japanese Patent No. 3851060

  By the way, in an automated production line such as a processing line or an assembly line, two production apparatuses adjacent to each other in order to ensure a stable production amount even if there is a variation in operation time between the production apparatuses or an abnormality occurs. A buffer may be provided between the two.

  However, in the method of Patent Document 1 described above, when an abnormality or the like occurs in one production apparatus, it is determined that the upstream production apparatus and the downstream production apparatus are in a standby state, and the power consumption reduction control stops operation. I do. In other words, when the method of Patent Document 1 described above is performed on a production line provided with a buffer, the upstream production apparatus and the downstream production apparatus adjacent to the stopped production apparatus are also powered regardless of the number of workpieces in the buffer. Consumption reduction control is performed. Therefore, there is a problem that the stability of production is lowered.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to efficiently reduce power consumption without impairing production stability in a production apparatus that takes a step in a production line having a buffer between production apparatuses.

  The production apparatus control method of the present invention includes a work unit that performs work on a work, and a power consumption reduction control unit that performs power consumption reduction control so as to reduce power supplied to the work unit. An upstream buffer for holding a work before work by the work unit is arranged between the production apparatus and a downstream buffer for holding a work after work by the work unit between the production apparatus and the downstream production apparatus. In the control method of the production apparatus that is responsible for one step of the production line, the first threshold setting step for setting the first threshold Tu1 as the lower limit of the number of works to be retained in the upstream buffer, and the downstream buffer A second threshold value setting step for setting an upper limit second threshold value Tl1 for the number of workpieces to be retained, and a third threshold value Tu2 for an upper limit for the number of workpieces to be retained in the upstream buffer. A third threshold value setting step; a fourth threshold value setting step for setting a fourth threshold value Tl2 which is a lower limit of the number of workpieces retained in the downstream buffer; and an upstream indicating the number of workpieces remaining in the upstream buffer. A first counting step for counting the number of buffers Nu, a second counting step for counting the number Nl of downstream buffers indicating the number of works remaining in the downstream buffer, and the number of upstream buffers Nu is the third number A first threshold value determining step for determining whether or not the downstream buffer number Nl is equal to or greater than a threshold value Tu2 and equal to or less than the fourth threshold value Tl2, and the upstream buffer number Nu is determined to be the first threshold value in the first threshold value determining step. When the threshold value Tu2 of 3 or more and the downstream buffer number Nl is determined not to be less than or equal to the fourth threshold value Tl2, the upstream buffer number Nu is less than or equal to the first threshold value Tu1 or A second threshold value determining step for determining whether or not the downstream buffer number Nl is equal to or greater than the second threshold value Tl1, and the upstream buffer number Nu is the first threshold value Tu1 in the second threshold value determining step. Or a power consumption reduction control step for executing the power consumption reduction control by the power consumption reduction control means when the number of downstream buffers Nl is determined to be equal to or greater than the second threshold Tl1; When it is determined in the determination step that the number of upstream buffers Nu is not less than the third threshold value Tu2 and the number of downstream buffers Nl is not more than the fourth threshold value Tl2, the power consumption reduction by the power consumption reduction control means. And a power consumption reduction control stop step for stopping the control.

  The program of the present invention includes a work unit that performs work on a work, and power consumption reduction control means that performs power consumption reduction control so as to reduce power supplied to the work unit, and an upstream production apparatus An upstream buffer for holding a work before work by the work unit is arranged between the upstream buffer and a downstream buffer for holding a work after work by the work unit is placed between the work unit and the downstream production apparatus. A first threshold value setting step for setting a first threshold value Tu1 as a lower limit of the number of works to be retained in the upstream buffer in a computer of the production apparatus that is responsible for one process of the production line, and a work to be retained in the downstream buffer A second threshold value setting step for setting a second threshold value Tl1 that is the upper limit of the number of workpieces, and a third threshold value Tu2 that is an upper limit for the number of workpieces to be retained in the upstream buffer. Threshold setting step, a fourth threshold setting step for setting a fourth threshold Tl2 which is a lower limit of the number of works to be retained in the downstream buffer, and an upstream buffer number indicating the number of works remaining in the upstream buffer A first counting step of counting Nu, a second counting step of counting the number of downstream buffers Nl indicating the number of works remaining in the downstream buffer, and the upstream buffer number Nu being the third threshold value Tu2 The first threshold value determining step for determining whether or not the downstream buffer number Nl is equal to or smaller than the fourth threshold value Tl2 and the upstream buffer number Nu in the first threshold value determining step is the third threshold value. When it is determined that the number of downstream buffers N1 is not less than the fourth threshold value Tl2 and not less than the threshold value Tu2, the upstream buffer number Nu is not more than the first threshold value Tu1 or before A second threshold value determining step for determining whether or not the number of downstream buffers Nl is equal to or greater than the second threshold value Tl1, and the upstream buffer number Nu is equal to or less than the first threshold value Tu1 in the second threshold value determining step. Alternatively, when it is determined that the number of downstream buffers Nl is equal to or greater than the second threshold value Tl1, a power consumption reduction control step for executing the power consumption reduction control by the power consumption reduction control unit, and the first threshold value determination When it is determined in the step that the number of upstream buffers Nu is not less than the third threshold value Tu2 and the number of downstream buffers Nl is not more than the fourth threshold value Tl2, the power consumption reduction control by the power consumption reduction control means is performed. The power consumption reduction control stop process for stopping the operation is executed.

  The recording medium of the present invention is a computer-readable medium on which the program is recorded.

  According to the present invention, the number of upstream buffers between upstream production apparatuses and the number of downstream buffers between downstream production apparatuses are counted, and power consumption reduction control is executed and stopped by judging the threshold value of the number. Yes. Thereby, it is possible to keep the number of buffers between the upstream and downstream production apparatuses in an appropriate state. Therefore, in a production line having a buffer between production apparatuses, the number of buffers contributes to the production stability, so that it is possible to reduce power consumption without impairing the production stability.

It is explanatory drawing which shows schematic structure of the production line which concerns on embodiment of this invention, (a) is a figure which shows arrangement | positioning relationship of the production apparatus and buffer of a production line, (b) is schematic structure of each production apparatus of a production line It is explanatory drawing which shows. It is a flowchart which shows the setting operation | movement of the threshold value by the control apparatus with respect to the buffer number of each buffer. It is a flowchart for demonstrating the timing which judges execution and a stop of the power consumption reduction control by a control apparatus. It is a figure for demonstrating the change of the buffer number between apparatuses when each production apparatus is arrange | positioned to a production line, (a) is immediately after line operation, (b) is 11.9 minutes after line operation. The state, (c) shows the state 12.2 minutes after the line operation. (D) shows a state after 27.8 minutes after the line operation, and (e) shows a state after 29.6 minutes after the line operation. It is a flowchart at the time of setting change of threshold value Tu2, Tl2 in a control apparatus.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. FIG. 1 is an explanatory diagram showing a schematic configuration of a production line according to an embodiment of the present invention. As shown in FIG. 1A, a production line 300 includes a plurality of production apparatuses 100 ₁ , 100 ₂ , 100 ₃ , 100 ₄ and a work W that is an in-process product provided between two adjacent production apparatuses. and a buffer _{200 1,} 200 2, 200 ₃ that leaves a. For example, the upstream production apparatus 100 _2, upstream of the production device 100 ₁ is disposed on the downstream of the production device 100 _2, downstream of the production device 100 ₃ is disposed. Between the said production device 100 ₂ and upstream of the production device 100 _1, buffer 200 _first upstream keep the workpiece W is disposed between the production apparatus 100 ₂ and downstream of the production device 100 ₃ the buffer 200 ₂ of downstream keep the workpiece W is arranged. Each production apparatus 100 ₁ , 100 ₂ , 100 ₃ , 100 ₄ is responsible for one process of the production line 300.

  As shown in FIG. 1B, each production device 100 includes a control device 1 that is a computer, a storage device 2 connected to the control device 1, a communication device 3 connected to the control device 1, and a control device. 1 is provided with an input device 4 connected to 1 and an arithmetic device 5 connected to the control device 1. Each production apparatus 100 includes a plurality of work units 6 and 7 and a switch circuit 8 for switching the supply / cutoff of the power of the power supply 9 to each of the work units 6 and 7.

  The storage device 2 stores a program for operating the control device 1, and the control device 1 reads out the program stored in the storage device 2 and executes various processes. In addition, the storage device 2 also functions as a storage unit that stores a calculation processing result by the control device 1. The communication device 3 is configured to exchange information with the communication device 3 of the upstream / downstream production device 100. The input device 4 inputs various data to the control device 1 by an operator's operation. The work units 6 and 7 are, for example, work robots, which transport the work W transferred to the upstream buffer 200 to a work table (not shown), and perform work such as predetermined assembly on the work W. W is applied to W and transported to the downstream buffer 200. The switch circuit 8 is in an ON state in which power is supplied to the work units 6 and 7 by an ON signal from the control device 1 and an OFF state in which supply of power to the work units 6 and 7 is interrupted by an OFF signal. It will be switched.

In the above configuration, in FIG. 1 (a), the buffer 200 ₁ of the upstream with respect to the production device 100 _2, the workpiece W before work by the working units 6 and 7 of the production apparatus 100 ₂ so that the are fastened. Further, the buffer 200 ₂ downstream with respect to the production device 100 _2, the work W after the work by the work units 6 and 7 of the production apparatus 100 ₂ so that the are fastened.

  In the present embodiment, the control device 1 executes a program stored in the storage device 2 as power consumption reduction control means for performing power consumption reduction control so as to reduce the power supplied to the work units 6 and 7. Function. Specifically, the control device 1 controls the switching operation of the switch circuit 8. In the present embodiment, reducing the power supplied to the work units 6 and 7 means cutting off the power supplied to the work units 6 and 7.

Further, in the present embodiment, the control device 1 is adapted to count the upstream buffer number Nu indicating the number of the workpiece W remains upstream of the buffer 200 _1, the number of the workpiece W remains in the downstream of the buffer 200 ₂ The number of downstream buffers Nl shown is configured to be counted.

Specifically, the control device 1 first causes the storage device 2 to store the number of times the workpiece W has been loaded and the number of times the workpiece W has been unloaded. It is 0 in the initial state, and when the workpiece W is loaded, 1 is added to the loading count, and when the workpiece W is unloaded, 1 is added to the loading count. Further, transmits upstream of the production device 100 ₁ when updated the carry number of the workpiece W to carry the number of the workpiece W, unloading times of the workpiece W to the downstream production apparatus 100 ₃ at the time of updating the out count of the workpiece W Send.

If withdrawn workpiece W in the buffer 200 in the _first upstream inspection and rework the like, the operator inputs a sampling number from the input device 4, it may be corrected so as to add that number to carry the number of the workpiece W . When turned on again sampling and drawn the workpiece W in the workpiece W of the downstream buffer 200 in ₂ also can cope with the operator's manual operation the same concept.

The control device 1 of the production apparatus 100 _2, at the time of receiving the carry-out number of times and upstream production apparatus 100 ₁ of the workpiece W updating the loading times of the workpiece W, out of the upstream production apparatus 100 ₁ of the workpiece W The upstream buffer number Nu is calculated by subtracting the number of times the work W is carried in from the number of times. The calculated upstream buffer number Nu is stored in the storage device 2. The control of the production apparatus 100 ₂ device 1, upon receiving the carry-number of the workpiece W at the time updated the unloading times and downstream production apparatus 100 ₃ of the workpiece W, carrying the downstream production apparatus 100 ₃ of the workpiece W The downstream buffer number Nl is calculated by subtracting the number of unloading of the workpiece W from the number of times. The calculated downstream buffer number Nl is stored in the storage device 2. By the operation of the control device 1 described above, the upstream buffer number Nu and the downstream buffer number Nl are counted.

FIG. 2 is a flowchart showing the threshold value setting operation by the control device 1 for the number of buffers 200 ₁ and 200 ₂ . The control device 1 can set each threshold value by operating based on a program stored in the storage device 2. As shown in FIG. 2, the control device 1 sets a first threshold value Tu1, a second threshold value Tl1, a third threshold value Tu2, and a fourth threshold value Tl2 (S1 to S4). These threshold values are set in advance before line operation. Here, the line operation means that each production device 100 receives an instruction to end production from each production device 100 when each production device 100 receives an instruction to start production and stops production operation. Until the point of time.

In this embodiment, the third threshold Tu2 and fourth threshold Tl2 is input from the input device 4 of the production apparatus 100 ₂ by the operator are stored in the storage device 2 by the control device 1. That is, the control device 1 sets the third threshold value Tu2 and the fourth threshold value Tl2 to values instructed by the operator's operation (S1, S2: third threshold value setting step, fourth threshold value setting step). . Hereinafter, the third threshold ² Tu2 set in the production device 100 _2, the fourth threshold value is represented as ² Tl2, third ³ threshold Tu2 that is set downstream of the production apparatus 100 _3, upstream of the a fourth threshold value which is set in the production device 100 ₁ is indicated as ¹ Tl2 be described.

Then, the communication device 3 of the production apparatus 100 ₂ under the control of the control device 1, and transmits the information of the third threshold value ² Tu2 upstream production apparatus 100 _1, the information of the fourth threshold value ² Tl2 sending downstream of the production apparatus 100 _3. At this time, the downstream production apparatus 100 ₃ located downstream of the production device 100 _2, the information of the third threshold value ³ Tu2 is transmitted that has been set, the production of an upstream located upstream of the production device 100 ₂ from device 100 _1, the information of the fourth threshold value ¹ Tl2 that has been set is transmitted.

Therefore, the communication device 3 of the production apparatus 100 ₂ receives the third threshold value ³ Tu2 information of which is transmitted by the downstream production apparatus 100 _3, the fourth threshold value is transmitted by the upstream production apparatus 100 ₁ ¹ The information of Tl2 is received.

The fourth threshold value ¹ Tl2 of the production apparatus 100 ₂ upstream of the production apparatus 100 ₁ as the first threshold Tu1 of the production device 100 _2, the production apparatus of the third threshold value ³ Tu2 downstream production apparatus 100 ₃ stored in the storage device 2 as a second threshold Tl1 100 _2. That is, the control device 1 of the production apparatus 100 _2, the first threshold Tu1, set to the same value as the fourth threshold value ¹ Tl2 which is set upstream of the production device 100 ₁ (S3: first threshold value setting Process). The control device 1 of the production apparatus 100 _2, the second threshold value Tl1, set to the same value as the third threshold value ³ Tu2 that is set downstream of the production apparatus 100 ₃ (S4: second threshold setting Process).

Here, the first threshold Tu1 is set in the production device 100 ₂ indicates a lower limit value of the number of work W to remain upstream of the buffer 200 _1, the second threshold Tl1 is downstream of the buffer 200 ₂ The upper limit value of the number of workpieces W to be retained is shown. The third threshold Tu2 to be set in the production device 100 ₂ indicates the upper limit value of the number of work W to remain upstream of the buffer 200 _1, the fourth threshold Tl2 is downstream of the buffer 200 ₂ The lower limit value of the number of works W to be fastened is shown.

That is, the first threshold Tu1 is a threshold for the upstream buffer number Nu for the production apparatus 100 ₂ when the upstream production apparatus 100 ₁ is stopped due to an abnormality or the like is running. The second threshold Tl1 is a threshold for the downstream buffer number Nl to the production apparatus 100 ₂ when the downstream production apparatus 100 ₃ and stopped by abnormality is running. In other words, means that the time in which the production apparatus 100 ₂ can continue to operate when the upstream production apparatus 100 ₁ as the number of upstream buffer Nu is smaller is stopped is shorter, the first threshold Tu1 is its time This is a threshold value for determining that the value is shorter than the allowable level. Also means that the time in which the production apparatus 100 ₂ can continue to work when the larger downstream buffer number Nl downstream production apparatus 100 ₃ stopped is shortened, the second threshold Tl1 is allowed that time It is a threshold value for determining that the level is shorter than the level.

  Here, an abnormality is when the preconditions for operating the production apparatus 100 are no longer satisfied even though the production apparatus 100 is being operated (for example, when there are no parts to be supplied or the robot is overrun). When operation stops due to an error such as current).

The third threshold Tu2 is a threshold for the upstream buffer number Nu for upstream production apparatus 100 ₁ in the production apparatus 100 ₂ is stopped due to an abnormality or the like is running. The fourth threshold Tl2 is a threshold for the downstream buffer number Nl to the downstream production apparatus 100 ₃ when the production apparatus 100 ₂ is stopped due to an abnormality or the like is running. In other words, as the number of upstream buffer Nu is large, meaning that the time the production apparatus 100 ₁ of the upstream can continue to work when the production apparatus 100 ₂ is stopped is shortened, the third threshold Tu2 its time Is a threshold value for determining that the value is shorter than the allowable level. Also, as the number of the downstream buffer Nl is small, means that the time the downstream production apparatus 100 ₃ can continue to work when the production apparatus 100 ₂ is stopped is shortened, the fourth threshold Tl2 has its time This is a threshold value for determining that the value is shorter than the allowable level.

Above, the first threshold Tu1 of the production apparatus 100 ₂ is set to the same value as the fourth threshold value ¹ Tl2 which is set upstream of the production device 100 _1, the second threshold Tl1 of the production apparatus 100 ₂ It is set to the same value as the third threshold value ³ Tu2 that is set downstream of the production apparatus 100 _3. That is, aligned with the production apparatus 100 ₂ in buffer 200 ₁ of a lower limit of upstream on the basis threshold and a lower threshold value of the downstream buffer 200 ₁ relative to the upstream production device 100 _1. Also, in alignment with the upper threshold of the production apparatus 100 ₂ downstream of the buffer 200 ₂ relative to the, and a downstream production apparatus 100 ₃ upstream of the upper limit of the buffer 200 _second threshold relative to the.

  In this embodiment, each threshold value is set to a value equal to or greater than 0 and equal to or less than the maximum number of works that can be retained in the buffer. For example, the first threshold Tu1 is set to “1”, the second threshold Tl1 is set to “4”, the third threshold Tu2 is set to “4”, and the fourth threshold Tl2 is “1”. Set to

  FIG. 3 is a flowchart for explaining the timing for determining execution and stop of the power consumption reduction control by the control device 1. The control device 1 reads the program stored in the storage device 2 and executes the following processing.

First, the control device 1 counts the number of upstream buffers Nu (S11: first counting step) and counts the number of downstream buffers Nl (S12: second counting step). Next, the controller 1 determines whether a request signal has been received from the downstream of the production apparatus 100 ₃ to request to stop power consumption reduction control (S13: request signal reception determination step).

  Next, when it is determined that the request signal has been received in step S13 (S13: YES), the control device 1 determines whether the upstream buffer number Nu is equal to or less than the first threshold value Tu1 (S14: request). Signal transmission judgment process).

Next, when the control device 1 determines in step S14 that the number of upstream buffers Nu is equal to or less than the first threshold value Tu1 (S14: YES), the control device 1 sends the request signal upstream by the communication device 3 functioning as a request signal transmission unit. sending of the production apparatus 100 ₁ (S15: request signal transmission step). In other words, the number of upstream buffer Nu cases is less than the first threshold Tu1, since the number of the upstream buffer Nu is close to the number "0" or a value that must be stopped the production apparatus 100 _2, upstream of the production device 100 ₁ , a request signal is transmitted so as to stop the power consumption reduction control.

  Next, after the communication device 3 transmits the request signal, the control device 1 determines whether or not the upstream buffer number Nu is 0 (S16: upstream buffer number determination step). Note that if the control device 1 determines in step S14 that the upstream buffer number Nu is not equal to or less than the first threshold value Tu1 (S14: NO), the control device 1 executes the determination process in step S16.

  Next, the control device 1 determines that the request signal is not received in step S13 (S13: NO) or determines that the upstream buffer number Nu is 0 in step S16 (S16: NO). The following determination process is executed. That is, the control device 1 determines whether the upstream buffer number Nu is equal to or greater than the third threshold value Tu2 and the downstream buffer number Nl is equal to or less than the fourth threshold value Tl2 (S17: first threshold value determination step).

  Next, when the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not less than or equal to the fourth threshold value Tl2 (S17: NO), the control device 1 executes the following determination process. That is, the control device 1 determines whether the upstream buffer number Nu is equal to or smaller than the first threshold value Tu1 or the downstream buffer number Nl is equal to or larger than the second threshold value Tl1 (S18: second threshold value determining step).

  Next, when it is determined that the upstream buffer number Nu is equal to or smaller than the first threshold value Tu1 or the downstream buffer number Nl is equal to or larger than the second threshold value Tl1 (S18: YES), the control device 1 switches the switch circuit 8 to OFF. The power consumption reduction control is executed (S19: power consumption reduction control step).

  That is, the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not less than the fourth threshold value Tl2, and the upstream buffer number Nu is not more than the first threshold value Tu1 or the downstream buffer number Nl is not less than the second threshold value Tl1. In the case above, power consumption reduction control is executed.

  After determining that the power consumption reduction control is to be executed, the control device 1 performs the necessary preprocessing and then issues a switch OFF instruction to the switch circuit 8. For example, when the work units 6 and 7 are powered off like a work robot, they move in the direction of gravity due to their own weight, causing damage to parts, jigs, and the unit itself in the device. . When the switch circuit 8 is turned off, the power supply 9 of the corresponding work unit 6, 7 is cut off, and the power consumption is reduced. The control apparatus 1 returns to the process of step S11 after performing the above power consumption reduction control.

  Note that if the control device 1 determines in step S18 that the upstream buffer number Nu is not equal to or smaller than the first threshold value Tu1 or the downstream buffer number Nl is not equal to or larger than the second threshold value Tl1 (S18: NO), the power consumption is reduced. Control is not executed, the next work is carried in and work is started.

Next, when the control device 1 determines in step S16 that the upstream buffer number Nu is not 0 (S16: YES), the control device 1 executes the following determination processing. Alternatively, when the upstream buffer number Nu is equal to or larger than the third threshold value Tu2 and the downstream buffer number Nl is equal to or smaller than the fourth threshold value Tl2 in step S17 (S17: YES), the control device 1 executes the following determination process. . That is, the control device 1 determines whether or not the power consumption reduction control is being executed (S20). Control device 1, when it is determined that the running power consumption reduction control (S20: YES), stops the power consumption reduction control (S21: power consumption reduction control stopping step), the upstream of the workpiece from the buffer 200 ₁ The work units 6 and 7 are controlled so as to carry in and start work. The control device 1, when it is determined that it is not running the power consumption reduction control (S20: NO), has already been stopped power consumption reduction control, carries the work from the buffer 200 ₁ of upstream work Each work unit 6, 7 is controlled to start.

  Here, after determining that the power consumption reduction control is to be stopped, the control device 1 issues a switch ON instruction to the switch circuit 8 and then executes necessary post-processing. Post-processing is, for example, sensor calibration processing or robot brake release processing.

FIG. 4 is a diagram for explaining a change in the number of buffers between apparatuses when each production apparatus is arranged on a production line. The production line 300 includes a production apparatus 100 ₁ , a production apparatus 100 ₂ , a production apparatus 100 _3, and a production apparatus 100 ₄ . Between each production apparatus, the buffer _{200 1,} 200 2, 200 ₃ are arranged.

The production apparatus 100 ₁ sufficient part is turned, the workpiece W taken out from the production apparatus 100 ₄ is smoothly shipped. In addition, the operation times of the production apparatuses 100 _{1 to} 100 ₄ are 0.8 minutes, 0.6 minutes, 0.9 minutes, and 1 minute, respectively, and there is a difference in the operation time. In addition, it is assumed that each of the production apparatuses 100 _{1 to} 100 ₄ is stable and no abnormality occurs.

In the production apparatuses 100 ₁ to 100 ₄ , the third threshold value Tu2 is set to “4” and the fourth threshold value Tl2 is set to “1” in advance. In the production apparatuses 100 ₂ and 100 ₃ , the first threshold value Tu1 is set to “1” from the information on the fourth threshold value Tl2 received from the upstream production apparatus immediately before the line operation, and the downstream production apparatus The second threshold Tl1 is set to “4” from the received information on the third threshold Tu2.

Like the other production apparatuses 100 ₂ and 100 ₃ , the most downstream production apparatus 100 ₄ stores a threshold value Tu ₂ in advance by an operator's operation, and immediately before the line operation, information on the threshold value Tu 2 is stored in the upstream production apparatus 100 _3. Send. Further, as with the other production apparatuses 100 ₂ and 100 ₃ , the most downstream production apparatus 100 ₄ transmits information on the number of work carry-in times to the upstream production apparatus 100 ₃ when the work carry-in number is updated.

Further, unlike the other production apparatuses 100 ₂ and 100 ₃ , the most downstream production apparatus 100 ₄ has an upstream position when the number of buffers 200 ₃ between the upstream production apparatus 100 ₃ becomes 1 or less. the production apparatus 100 ₃ transmits a request signal for requesting the stop of the power reduction control. Also, most downstream production apparatus 100 ₄ continues to transmit a request signal to the buffer number of the buffer 200 ₃ becomes 4 or more.

Like the most upstream production apparatus 100 ₁ is other production apparatus ₁₀₀ 2, 100 _3, previously stores threshold Tl2 by operation of an operator, transmits the information of the threshold Tl2 downstream production apparatus 100 ₂ in the immediately preceding line operation To do. Further, the production apparatus 100 ₁ of the most upstream transmits information of work unloading times downstream of the production apparatus 100 ₁ at the time of updating the number of work unloading.

Immediately after the line operation, as shown in FIG. 4A, all the buffers 200 ₁ to 200 ₃ are in a state of 0, and the production apparatus 100 ₄ requests the production apparatus 100 ₃ to stop the power consumption reduction control. To send a request signal.

In this case, the production apparatus 100 ₃ sends a request signal to the production apparatus 100 ₂ Since buffer 200 ₂ is 0 between the production apparatus 100 _2. Similarly production apparatus 100 ₂ also transmits a request signal to the production apparatus 100 _1. However, the production apparatus ₁₀₀ 2 - 100 ₄ buffer ₂₀₀ 1 to 200 ₃ between the upstream production apparatus ₁₀₀ 1 to 100 ₃ to perform power consumption reduction control because it is zero.

In the state after 11.9 minutes, as shown in FIG. 4 (b), the buffer 200 ₃ between the production apparatus 100 ₄ production apparatus 100 _3, one of the workpiece, the production apparatus 100 ₃ and the production device There are two works in the buffer 200 ₂ between 100 ₂ . In this case, the production apparatus 100 ₄ whereas that continuously sends request signals to produce 100 _3, the production apparatus 100 ₃ does not transmit a request signal to the production apparatus 100 _2. That is, in the production apparatus 100 _3, upstream buffer number Nu = 2, a first threshold Tu1 = 1, since the Nu> Tu1, according to the flowchart shown in FIG. 3, the request signal to stop the power consumption reduction control Do not send. Since the production apparatus 100 ₂ buffer between the production apparatus 100 ₁ is 0 running power consumption reduction control.

In the state after 12.2 minutes, as shown in FIG. 4C, two works are placed in the buffer 200 ₃ between the production apparatus 100 ₄ and the production apparatus 100 _3, and the production apparatus 100 ₃ and the production apparatus 100. the buffer 200 ₂ between ₂ there are one workpiece. Further, the buffer 200 ₁ between the production apparatus 100 ₂ and the production apparatus 100 ₁ there are one workpiece. In this case, the production apparatus 100 ₄ are continuously sends request signals to produce apparatus 100 _3.

Production apparatus 100 ₃ work in the buffer 200 ₂ between the production apparatus 100 ₂ transmits a request signal so became one. That is, the production apparatus 100 _3, upstream buffer number Nu = 1, since the threshold Tu1 = 1, according to the flowchart shown in FIG. 3, transmits a request signal.

Production device 100 ₂ is receiving a request signal from the production apparatus 100 ₃ and work in the buffer 200 ₁ between the production apparatus 100 ₁ stops the power consumption reduction control since the one. That is, the production apparatus 100 _2, since the production apparatus 100 ₃ and receives a request signal for stopping the power consumption reduction control, and a Nu ≠ 0, in accordance with the flowchart shown in FIG. 3, stops the power consumption reduction control To do.

Only a period of 0.3 minutes production device 100 ₂ from the time after 11.9 minutes time after 12.2 minutes are continuously executed the power consumption reduction control. The most operating time long production apparatus 100 ₄ shorter time than 0.4 minute difference between the operating time of the production apparatus 100 _2. This is a state (Nu ≦ Tu1) in which the number of workpieces existing in the buffer between the devices immediately after operation is small (Nu ≦ Tu1), so that the production device that receives the request signal by transmitting the request signal to the upstream production device reduces power consumption. This is because the production speed was given priority as a result of stopping the control.

In the state after 27.8 minutes, as shown in FIG. 4D, the buffer 200 ₃ between the production apparatus 100 ₄ and the production apparatus 100 ₃ has three works, and the production apparatus 100 ₃ and the production apparatus 100 the buffer 200 ₂ between ₂ there are three work. Further, the buffer 200 ₁ between the production apparatus 100 ₂ and the production apparatus 100 ₁ there are one workpiece.

In this case, the production apparatus 100 ₄ sending the request signal to the production apparatus 100 _3. A work production apparatus 100 ₃ is present in the buffer 200 ₂ between the production apparatus 100 ₂ is three, not sending a request signal to the production apparatus 100 _2. That is, the production apparatus 100 _3, upstream buffer number Nu = 3, since the threshold Tu1 = 1, in accordance with the flowchart of FIG. 3, not sending a request signal. Further, the production apparatus 100 ₂ is not receiving a request signal from the production apparatus 100 ₃ and so work that exists in the buffer 200 ₁ between the production apparatus 100 ₁ is one, performing power consumption reduction control To do. That is, the production apparatus 100 ₂ are the upstream buffer number Nu = 1, is a Nu ≦ Tu1 (= 1), in accordance with the flowchart of FIG. 3, performing power consumption reduction control.

In the state after 29.6 minutes, as shown in FIG. 4E, the buffer 200 ₃ between the production apparatus 100 ₄ and the production apparatus 100 ₃ has three works, and the production apparatus 100 ₃ and the production apparatus 100 the buffer 200 ₂ between ₂ there are one workpiece. Further, the buffer 200 ₁ between the production apparatus 100 ₂ and the production apparatus 100 ₁ there are four buffers. In this case, the production apparatus 100 ₄ does not transmit the request signal to the production apparatus 100 _3. Production apparatus 100 ₂ are among workpiece 1 in the buffer 200 ₂ between the production apparatus 100 ₃ and so work that exists in the buffer 200 ₁ between the production apparatus 100 ₁ is four power consumption Stop reduction control. That is, the production device 100 _2, the upstream buffer number Nu = 4, a downstream buffer number Nl = 1, since it is Nu ≧ Tu2 (= 4) and Nl ≦ Tl2 (= 1), in accordance with the flowchart of FIG. 3, the power Stop consumption reduction control.

That is, only a period of 1.8 min production apparatus 100 ₂ up to the time after 29.6 minutes from the time after 27.8 minutes are continuously executed the power consumption reduction control. The most work long production apparatus 100 ₄ and longer than 0.4 minutes of the difference between the operating time of the production apparatus 100 _second time. This is continued production apparatus 100 _2, not received a request signal from the production apparatus 100 _3, followed by a state in which there is room in the buffer between the production apparatus Nu ≧ Tu2 and Nl ≦ Tl2, the power consumption reduction control As a result, the reduction of power consumption is prioritized.

With the above operation, the case of not receiving the request signal from the downstream production apparatus 100 _3, the number of upstream buffer Nu first threshold Tu1 (= 1) or less or downstream buffer number Nl is the second threshold value Tl1 ( = 4) When it is greater than or equal to, power consumption reduction control is executed. As a result, when the request signal is not received, the upstream buffer number Nu is suppressed from being smaller than the first threshold value Tu1, and the downstream buffer number Nl is larger than the second threshold value Tl1. It is suppressed. Further, when the upstream buffer number Nu is equal to or greater than the third threshold value Tu2 (= 4) and the downstream buffer number Nl is equal to or less than the fourth threshold value Tl2 (= 1), the power consumption reduction control is stopped and the work on the workpiece is not performed. Be started.

Thus the buffer 200 1, _{200 2,} 200 ₃ of the buffer number Nu, because Nl is stable is adjusted power reduction control of the number is performed, without impairing the stability of the production, reduce power consumption Is possible.

When the controller 1 determines that the number of upstream buffers Nu is 0 in step S16, the determination in step S17 is NO and the determination in step S18 is YES, so that power consumption reduction control is executed. Will be. That is, the control device 1 of the production apparatus 100 _2, even if receiving a request signal from the downstream of the production apparatus 100 _3, if there is no workpiece upstream of the buffer 200 _1, the power consumption reduction control is executed. The control device 1 of the production apparatus 100 _2, work buffer 200 ₁ upstream when receiving a request signal from the downstream of the production device 100 _3. If even one power consumption reduction control is stopped. Thus, the production apparatus 100 ₂ receives the request signal from the downstream of the production apparatus 100 _3, since as running production speed priority, to supply the workpiece W stably to downstream equipment Can do.

  Here, considering that the power of the work units 6 and 7 is turned off / on again, there are many cases where the accompanying processing is necessary, and when the execution time of the power consumption reduction control is short, efficient power reduction can be performed. There may not be. For example, a device that operates in the direction of gravity due to its own weight when the power is turned off, such as a work robot, needs to apply a brake before turning off the power. Conversely, after the power is turned on again, the brake is released before the operation. is necessary. In such a case, even if the number of times is small, the effect of reducing the power consumption becomes larger by taking a longer duration of the power consumption reduction control. The power consumption reduction control can be continued for a longer time as the difference between the threshold Tu1 and the threshold Tu2 and the difference between the threshold Tl1 and the threshold Tl2 is increased.

  By the way, in this embodiment, the threshold values Tu2 and Tl2 set by the control device 1 by the operation of the operator are configured to be changed according to the operating rate of the work units 6 and 7 of the production apparatus 100. FIG. 5 is a flowchart when the threshold values Tu2 and Tl2 are changed in the control device 1.

  The control device 1 causes the arithmetic device 5 to measure the cumulative value of the time when the production device 100 is operated and the time when the production device 100 is stopped due to an abnormality, and stores the cumulative value in the storage device 2. Here, the abnormality of the production apparatus 100 is detected by the control device 1, and the time when the production apparatus 100 stops due to the abnormality is counted by the arithmetic device 5. The arithmetic device 5 starts timing when the control device 1 detects an abnormality, and the timing ends when the control device 1 cancels the abnormal state (for example, “abnormal” when there are no supply parts). For example, a state in which “supplied parts” are supplied). Then, the control device 1 calculates the operation rate by dividing the operation accumulation time by adding the operation stop time to the operation accumulation time (S31: operation rate calculation step). The calculated operation rate is stored in the storage device 2.

  The control device 1 changes the setting so that the third threshold value Tu2 decreases as the operating rate decreases (S32: third threshold value setting change step). Further, the control device 1 changes the setting so that the fourth threshold value Tl2 increases as the operating rate decreases (S33: fourth threshold value setting change step).

  Here, there are two reasons why the operating rate of the work units 6 and 7 of the production apparatus 100 is lowered. One of the causes is that the buffer between the upstream production apparatus and the production apparatus is filled with work. Thus, the upstream production equipment is to stop. The other cause is that there is no work in the buffer between the downstream production apparatus and the production apparatus, and the downstream production apparatus stops. These mean that production stability tends to be impaired.

  Therefore, for example, when the operation rate is 0.9 or less, the threshold value Tu2 is updated by 1 and the threshold value Tl2 is updated by 1 and when the operation rate is 0.8 or less, the threshold value Tu2 is decreased by 2. Tl2 is updated to be increased by 2. In this way, when production is stable, importance is placed on reducing power consumption as much as possible, and when production is unstable, importance is placed on production stability.

  That is, when the production apparatus is stopped by decreasing the threshold value Tu2, the time until the upstream production apparatus is stopped becomes longer, and when the production apparatus is stopped by increasing the threshold value Tl2, the downstream production apparatus is stopped. The time until it stops can be lengthened. That is, when the production apparatus stops due to an abnormality, it is possible to increase the margin for the time for the operator to perform the recovery process, leading to improved production stability.

  Although the present invention has been described based on the above embodiment, the present invention is not limited to this. In the above embodiment, the third threshold value Tu2 and the fourth threshold value Tl2 are set in the control device 1 according to an operator's instruction, and the first threshold value Tu1 and the second threshold value Tl1 are threshold values transmitted from upstream and downstream production devices. However, this is not a limitation. The control device 1 may also set the first threshold value Tu1 and the second threshold value Tl1 in accordance with an operator instruction.

  The recording medium storing the program read by the computer may be a medium such as a ROM, HDD, CD, or DVD, or a non-volatile memory such as a USB memory. In other words, any recording medium may be used as long as the program can be read by the computer, and the present invention is not limited to these.

  A program that causes a computer to realize the functions of the above-described embodiments may be supplied to a computer via a network or various recording media, and the computer may read and execute the program code. In this case, the program and a computer-readable recording medium recording the program constitute the present invention.

DESCRIPTION OF SYMBOLS 1 ... Control apparatus, 2 ... Memory | storage device, 3 ... Communication apparatus, 4 ... Input device, 6, 7 ... Work unit, 8 ... Switch circuit, 9 ... Power supply, 100 ... Production apparatus, 200 ... Buffer, 300 ... Production line, Nl ... downstream buffer number, Nu ... upstream buffer number, Tl1 ... second threshold, Tl2 ... fourth threshold, Tu1 ... first threshold, Tu2 ... third threshold

Claims (6)

A work unit that performs work on the work, and a power consumption reduction control unit that performs power consumption reduction control so as to reduce power supplied to the work unit, and the work unit between the upstream production apparatus An upstream buffer for holding the work before work by is arranged, and a downstream buffer for holding the work after work by the work unit is arranged between the downstream production apparatus and one step of the production line. In the control method of the production equipment
A first threshold value setting step for setting a first threshold value Tu1 as a lower limit of the number of works to be retained in the upstream buffer;
A second threshold value setting step of setting a second threshold value Tl1 as an upper limit of the number of works to be retained in the downstream buffer;
A third threshold setting step of setting a third threshold Tu2 as an upper limit of the number of works to be retained in the upstream buffer;
A fourth threshold setting step of setting a fourth threshold Tl2 as a lower limit of the number of works to be retained in the downstream buffer;
A first counting step of counting an upstream buffer number Nu indicating the number of works remaining in the upstream buffer;
A second counting step of counting the number Nl of downstream buffers indicating the number of works remaining in the downstream buffer;
A first threshold value determining step of determining whether or not the upstream buffer number Nu is equal to or greater than the third threshold value Tu2 and the downstream buffer number Nl is equal to or less than the fourth threshold value Tl2;
If it is determined in the first threshold value determining step that the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not less than the fourth threshold value Tl2, the upstream buffer number Nu is A second threshold value determining step for determining whether the first threshold value Tu1 or less or the number of downstream buffers Nl is equal to or greater than the second threshold value Tl1;
When it is determined in the second threshold value determining step that the upstream buffer number Nu is not more than the first threshold value Tu1 or the downstream buffer number Nl is not less than the second threshold value Tl1, the power consumption reduction control means A power consumption reduction control step of executing the power consumption reduction control according to
When it is determined in the first threshold value determining step that the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not more than the fourth threshold value Tl2, the power consumption reduction control means And a power consumption reduction control stopping step of stopping the power consumption reduction control according to the above. The production apparatus includes request signal transmission means for transmitting a request signal for requesting the upstream production apparatus to stop the power consumption reduction control,
A request signal reception determination step of determining whether or not the request signal has been received from the downstream production apparatus;
A request signal transmission determination step of determining whether or not the number of upstream buffers Nu is equal to or less than the first threshold value Tu1 when it is determined that the request signal is received in the request signal reception determination step;
When the request signal transmission determining step determines that the upstream buffer number Nu is equal to or less than the first threshold value Tu1, the request signal transmission means transmits the request signal to the upstream production apparatus. Process,
An upstream buffer number determination step of determining whether or not the upstream buffer number Nu is 0 when it is determined that the request signal is received in the request signal reception determination step;
In the power consumption reduction control step, when the upstream buffer number Nu is determined to be 0 in the upstream buffer number determination step, the power consumption reduction control by the power consumption reduction control unit is executed,
In the power consumption reduction control stop step, when it is determined in the upstream buffer number determination step that the upstream buffer number Nu is not 0, the power consumption reduction control by the power consumption reduction control means is stopped. The method for controlling a production apparatus according to claim 1, further comprising: An operation rate calculation step of calculating an operation rate of the work unit;
A third threshold setting changing step for changing the setting so that the third threshold Tu2 decreases as the operating rate decreases;
The production method according to claim 1, further comprising: a fourth threshold value setting change step for changing the setting so that the fourth threshold value Tl2 increases as the operating rate decreases. Control method of the device. In the first threshold value setting step, the first threshold value Tu1 is set to the same value as the fourth threshold value set in the upstream production apparatus,
4. The method according to claim 1, wherein, in the second threshold value setting step, the second threshold value Tl <b> 1 is set to the same value as a third threshold value set in the downstream production apparatus. 5. 2. A method for controlling a production apparatus according to item 1. A work unit that performs work on the work, and a power consumption reduction control unit that performs power consumption reduction control so as to reduce power supplied to the work unit, and the work unit between the upstream production apparatus An upstream buffer for holding the work before work by is arranged, and a downstream buffer for holding the work after work by the work unit is arranged between the downstream production apparatus and one step of the production line. To the computer of the production equipment
A first threshold value setting step for setting a first threshold value Tu1 as a lower limit of the number of works to be retained in the upstream buffer;
A second threshold value setting step of setting a second threshold value Tl1 as an upper limit of the number of works to be retained in the downstream buffer;
A third threshold setting step of setting a third threshold Tu2 as an upper limit of the number of works to be retained in the upstream buffer;
A fourth threshold setting step of setting a fourth threshold Tl2 as a lower limit of the number of works to be retained in the downstream buffer;
A first counting step of counting an upstream buffer number Nu indicating the number of works remaining in the upstream buffer;
A second counting step of counting the number Nl of downstream buffers indicating the number of works remaining in the downstream buffer;
A first threshold value determining step of determining whether or not the upstream buffer number Nu is equal to or greater than the third threshold value Tu2 and the downstream buffer number Nl is equal to or less than the fourth threshold value Tl2;
If it is determined in the first threshold value determining step that the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not less than the fourth threshold value Tl2, the upstream buffer number Nu is A second threshold value determining step for determining whether the first threshold value Tu1 or less or the number of downstream buffers Nl is equal to or greater than the second threshold value Tl1;
When it is determined in the second threshold value determining step that the upstream buffer number Nu is not more than the first threshold value Tu1 or the downstream buffer number Nl is not less than the second threshold value Tl1, the power consumption reduction control means A power consumption reduction control step of executing the power consumption reduction control according to
When it is determined in the first threshold value determining step that the upstream buffer number Nu is not less than the third threshold value Tu2 and the downstream buffer number Nl is not more than the fourth threshold value Tl2, the power consumption reduction control means And a power consumption reduction control stop step for stopping the power consumption reduction control according to.   A computer-readable recording medium on which the program according to claim 5 is recorded.

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