EP3951038A1

EP3951038A1 - Yarn management system

Info

Publication number: EP3951038A1
Application number: EP21187111.6A
Authority: EP
Inventors: Akihiro Ueyama; Yasuo SHIMOYAMA; Yoshiyuki Komura
Original assignee: Shima Seiki Mfg Ltd
Current assignee: Shima Seiki Mfg Ltd
Priority date: 2020-08-05
Filing date: 2021-07-22
Publication date: 2022-02-09
Anticipated expiration: 2041-07-22
Also published as: EP3951038B1; CN114057031A; KR102573658B1; JP2022029477A; JP7460477B2; CN114057031B; KR20220017846A

Abstract

The disclosure includes a yarn remaining amount detector 10 that detects a yarn remaining amount as a remaining amount of a knitting yarn Y of a yarn cone 141 disposed in a flat knitting machine 100, a storage 20 that stores knitting data of a knitted fabric K, a controller 50 that manages the knitting yarn Y to be fed to the flat knitting machine 100, and at least one of a yarn conveyor 30 that conveys the yarn cone 141 to the flat knitting machine 100 or a yarn exchanger 40 that exchanges the yarn cone 141 disposed in the flat knitting machine 100 with a new yarn cone 141, in which upon determination of presence of the yarn cone 141 satisfying a management condition calculated based on the yarn remaining amount and the knitting data, the controller 50 manages the knitting yarn Y of the yarn cone 141 by the at least one of the yarn conveyor 30 or the yarn exchanger 40.

Description

TECHNICAL FIELD

The disclosure relates to a technique of a yarn management system that manages a yarn to be fed to a knitting machine.

BACKGROUND ART

Conventionally, there is known a technique of a yarn management system for managing a yarn to be fed to a knitting machine. The technique is disclosed in, for example, JP H08-277069 A .
JP H08-277069 A discloses detecting presence or absence of the yarn wound around a cone by detecting reflected light from a surface of the yarn wound around the cone. In the technique disclosed in JP H08-277069 A , when the cone runs out of the yarn, a control unit displays an abnormal state on a display and stops the knitting machine. An operator can know presence or absence of the yarn on the cone only by looking at the display, and can immediately exchange the cone having run out of the yarn with a new cone. The yarn to be fed to the knitting machine is managed in this way.

SUMMARY OF INVENTION

However, in the technique disclosed in JP H08-277069 A , the yarns are exchanged after the cone runs out of the yarn, and thus the knitting machine needs to be stopped. For this reason, there is a problem such as a decrease in production efficiency. Therefore, optimization of yarn management is desired.
The disclosure has been made in view of the above circumstances, and an object of the disclosure is to provide a yarn management system capable of optimizing management of a yarn.
An object of the disclosure is as described above, and hereinafter, measures to take in order to achieve this object will be described.
That is, a yarn management system according to the disclosure includes a yarn remaining amount detector configured to detect a yarn remaining amount as a remaining amount of a yarn disposed in a knitting machine, a storage configured to store knitting data of a knitted fabric, a controller configured to manage a yarn to be fed to the knitting machine, and at least one of a yarn conveyor configured to convey the yarn to the knitting machine or a yarn exchanger configured to exchange the yarn disposed in the knitting machine with a new yarn, in which upon determination of presence of the yarn satisfying a management condition calculated based on the yarn remaining amount and the knitting data, the controller manages the yarn by the at least one of the yarn conveyor or the yarn exchanger.
This configuration can optimize management of the yarn (yarn management). Specifically, the management condition is calculated based on both the yarn remaining amount and the knitting data, and yarn management (yarn conveyance and yarn exchange) is performed based on the management condition, and therefore the yarn management can be optimally performed.
Further, when the yarn having the yarn remaining amount less than or equal to a predetermined threshold value exists, the controller may determine that the yarn satisfies the management condition.
This configuration can prevent yarn exhaustion. Specifically, since the yarn management is performed when the yarn remaining amount becomes less than or equal to the predetermined threshold value, the knitting machine can be prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in production efficiency.
Upon determination of presence of the yarn not allowing knitting of the knitted fabric being knitted or the knitted fabric to be knitted next with the yarn remaining amount at a current point of time, the controller may determine that the yarn satisfies the management condition.
This configuration can prevent yarn exhaustion. Specifically, since the yarn management is performed when the knitted fabric being knitted or the knitted fabric to be knitted next cannot be knitted with the current yarn remaining amount, the knitting machine can be prevented from stopping due to yarn exhaustion, and this can eventually prevent a decrease in the production efficiency.
The disclosure may further include a yarn conveyor configured to convey the yarn to the knitting machine, in which the management condition may include a yarn conveyance condition, and upon determination of presence of the yarn satisfying the yarn conveyance condition in a plurality of the knitting machines, the controller may preferentially convey the yarn by the yarn conveyor in ascending order of the yarn remaining amount or in ascending order of time at which the yarn is exhausted.
This configuration can prevent yarn exhaustion. Specifically, since the yarn in which the yarn remaining amount is small or the time at which the yarn is exhausted is early is preferentially conveyed, the knitting machine can be prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in the production efficiency.
The disclosure may further include the yarn conveyor configured to convey the yarn to the knitting machine, in which the management condition may include the yarn conveyance condition, and upon determination of presence of the yarn satisfying the yarn conveyance condition in the plurality of knitting machines, the controller may acquire position information of the yarn conveyor and determine a conveyance order of the yarn based on the position information of the yarn conveyor that has been acquired.
This configuration can prevent yarn exhaustion. Specifically, for example, the time required for the yarn conveyance can be reduced by conveying the yarn first to the knitting machine located at a position close to the yarn conveyor.
The disclosure may further include a yarn exchanger configured to exchange the yarn disposed in the knitting machine with the new yarn, in which the management condition includes a yarn exchange condition, and the controller may exchange the yarn satisfying the yarn exchange condition by the yarn exchanger during a period when the yarn is not used for knitting based on the knitting data.
This configuration allows the yarn exchange to be performed without stopping the knitting machine. Specifically, the knitting machine can be prevented from stopping by performing the yarn exchange in a period in which the yarn is not used for the knitting (period in which the yarn carrier is not in operation).
The disclosure may further include the yarn exchanger configured to exchange the yarn disposed in the knitting machine with the new yarn, in which the management condition includes the yarn exchange condition, and upon determination that the yarn not allowing knitting of the knitted fabric to be knitted next with the yarn remaining amount at the current point of time exists and thus the yarn satisfies the yarn exchange condition, the controller may calculate how far the knitted fabric to be knitted next is to be knitted based on the yarn remaining amount and the knitting data, and then the controller may determine time to exchange the yarn in accordance with a calculation result.
This configuration can improve a usage rate of the yarn. Specifically, for example, when there is no margin in the yarn remaining amount at an end of the knitting of the knitted fabric currently being knitted, the yarn exchange is performed at this point of time. If there is a margin in the yarn remaining amount, the yarn exchange is performed after the knitted fabric to be knitted next is knitted partway. Thus, the yarn can be used maximally.
As an effect of the disclosure, an effect of optimizing the management of the yarn can be achieved.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1 is a front view illustrating an overall configuration of a flat knitting machine in which a yarn is managed by a yarn management system according to one embodiment of the disclosure;
Fig. 2 is a side view illustrating a configuration of needle beds and carriages;
Fig. 3 is a block diagram illustrating a configuration of a yarn management system according to one embodiment of the disclosure;
Fig. 4 is a flowchart of yarn conveyance instruction control;
Fig. 5 is a flowchart of yarn exchange instruction control;
Fig. 6 is a flowchart of yarn conveyance processing;
Fig. 7 is a flowchart of yarn exchange processing;
Fig. 8 is a flowchart of priority order setting processing according to a first embodiment;
Fig. 9 is a diagram illustrating an example of yarn conveyance and yarn exchange according to the first embodiment;
Fig. 10 is a flowchart of priority order setting processing according to a second embodiment;
Fig. 11 is a flowchart of priority order setting processing according to a third embodiment;
Fig. 12 is a diagram illustrating an example of yarn conveyance and yarn exchange according to the third embodiment;
Fig. 13 is a flowchart of priority order setting processing according to a fourth embodiment; and
Fig. 14 is a diagram illustrating an example of yarn conveyance and yarn exchange according to the fourth embodiment.

DESCRIPTION OF EMBODIMENTS

Hereinafter, directions indicated by arrows U, D, F, B, L, and R in the drawings are defined as up, down, front, rear, left, and right, respectively, and descriptions will be made accordingly.
A yarn management system 1 according to one embodiment of the disclosure manages a yarn to be fed to a flat knitting machine 100. Hereinafter, before the description of the yarn management system 1, the overall configuration of the flat knitting machine 100 will be first described with reference to Figs. 1 and 2.
As illustrated in Figs. 1 and 2, the flat knitting machine 100 mainly includes needle beds 110, carriages 120, a yarn guide rail 130, and a yarn stand 140.
The needle beds 110 are disposed so as to face each other at the front and rear across a needle bed gap S. The front and rear needle beds 110 are disposed in an inverted V shape in a side view so as to be inclined upward toward a center in the front and rear direction (direction facing each other) (see Fig. 2). Each of the needle beds 110 is provided with a large number of knitting needles 111 disposed side by side along a longitudinal direction (left and right direction) of each of the needle beds 110. The front and rear needle beds 110 can relatively move to the left and right when delivering and receiving (transferring) of a stitch are performed between the front and rear needle beds 110.
A pair of front and rear carriages 120 is disposed to face the front and rear needle beds 110 from above. The front and rear carriages 120 are connected by a bridge 120a disposed to straddle a plurality of the yarn guide rails 130. The carriages 120 can reciprocate along the longitudinal direction of the needle beds 110 by a servomotor (not shown). The carriages 120 are provided with a needle selecting mechanism (not shown) and a cam mechanism (not shown) for selectively operating the knitting needles 111 of the needle beds 110.
The plurality of yarn guide rails 130 are disposed above the needle bed gap S so as to extend along the longitudinal direction of the needle beds 110. A yarn carrier 131 (see Fig. 1) configured to feed a knitting yarn Y is supported on the yarn guide rails 130 so as to be movable.
The yarn stand 140 illustrated in Fig. 1 is provided with a yarn cone 141. The yarn cone 141 is formed by winding the knitting yarn Y around a cone 141a. In this embodiment, three yarn cones 141 are provided. The knitting yarns Y of the three yarn cones 141 are used in the knitting of the flat knitting machine 100, and for example, colors, yarn counts, and the like are different from each other. The knitting yarn Y from each yarn cone 141 is fed to the yarn carrier 131 through an appropriate yarn feeding path.
The flat knitting machine 100 configured as described above controls each part based on knitting data and the like created in advance. Specifically, the flat knitting machine 100 allows the carriages 120 to reciprocate along the longitudinal direction of the needle beds 110 by controlling operation of the servomotor. When reciprocating, the carriages 120 bring the yarn carrier 131 to be fed. In this case, knitting operations such as knit, tuck, miss, and the like, and the delivering and receiving of the stitches between the front and rear needle beds 110 can be performed by moving the knitting needles 111 forward and rearward with respect to the needle bed gap S by the cam mechanism (not shown) and the like placed on the carriages 120. A knitted fabric K is knitted by repeating such reciprocating movement of the carriages 120.
Next, the configuration of the yarn management system 1 will be described with reference to Fig. 3.
The yarn management system 1 manages (hereinafter, referred to as "yarn management") the knitting yarn Y to be fed to the flat knitting machine 100 in a factory or the like in which the flat knitting machine 100 is provided. Specifically, the yarn management system 1 manages the yarn cones 141 such that the yarn cone 141 disposed in the flat knitting machine 100 does not cause yarn exhaustion by conveying a new yarn cone 141 to the flat knitting machine 100 (hereinafter, referred to as "yarn conveyance") and exchanging the yarn cone disposed in the flat knitting machine 100 with the new yarn cone 141 (hereinafter, referred to as "yarn exchange"). In this embodiment, the yarn management system 1 performs the yarn conveyance and the yarn exchange for a plurality of the flat knitting machines 100.
The yarn management system 1 mainly includes a yarn remaining amount detector 10, a storage 20, a yarn conveyor 30, a yarn exchanger 40, and a controller 50.
The yarn remaining amount detector 10 detects a remaining length (hereinafter, referred to as "yarn remaining amount") of the knitting yarn Y wound around the cone 141a of the yarn cone 141. The yarn remaining amount detector 10 is disposed at an appropriate location, for example, disposed near the yarn cone 141 of the flat knitting machine 100. The yarn remaining amount detector 10 includes a light emitter (not shown) that irradiates a side surface of the knitting yarn Y of the yarn cone 141 with light, and a light receiver (not shown) that detects reflected light from a surface of the knitting yarn Y. The yarn remaining amount detector 10 can detect the yarn remaining amount based on a change in the reflected light detected by the light receiver. Note that the configuration of the yarn remaining amount detector 10 is not limited to the above configuration, and may be any configuration.
The storage 20 stores data such as knitting data used for the knitting of the knitted fabric K. The storage 20 stores the knitting data used in each flat knitting machine 100. The knitting data is sent to each flat knitting machine 100, and the flat knitting machine 100 can knit the knitted fabric K based on the knitting data.
The yarn conveyor 30 conveys the yarn. That is, the yarn conveyor 30 conveys the new unused yarn cone 141 to the flat knitting machine 100. In this embodiment, an automatic guided vehicle (AGV) is used as the yarn conveyor 30. The yarn conveyor 30 is configured to be able to travel on a predetermined travelling path provided between the plurality of flat knitting machines 100. The travelling path is formed to connect a storage location such as a warehouse for storing the new yarn cone 141 and each flat knitting machine 100 to each other. The yarn conveyor 30 can pick up the new yarn cone 141 at the storage location and convey the yarn cone 141 to a predetermined arrangement location of each flat knitting machine 100 by travelling on the travelling path.
The yarn exchanger 40 exchanges yarns of the flat knitting machine 100. The yarn exchanger 40 includes, for example, a splicer. The yarn exchanger 40 may include a knotter instead of the splicer. The yarn exchanger 40 is provided in each flat knitting machine 100. The yarn exchanger 40 cuts the knitting yarn Y of the old yarn cone 141 set on the yarn stand 140 at an arbitrary position as necessary, and connects an end of the knitting yarn Y and an end of the knitting yarn Y of the new yarn cone 141 conveyed by the yarn conveyor 30 so as not to form a knot. The yarn exchanger 40 can remove the cone 141a of the old yarn cone 141 set on the yarn stand 140 from the yarn stand 140, and set the new yarn cone 141 conveyed by the yarn conveyor 30 on the yarn stand 140.
The controller 50 controls operations of the yarn conveyor 30 and the yarn exchanger 40. The controller 50 includes a calculation processor such as a CPU and a storage such as a RAM and a ROM. The controller 50 acquires various information from the flat knitting machine 100. The controller 50 also acquires the yarn remaining amount of the yarn cone 141 from the yarn remaining amount detector 10. Further, the controller 50 acquires the knitting data from the storage 20. The controller 50 controls the operations of the yarn conveyor 30 and the yarn exchanger 40 based on the acquired information.
In the yarn management system 1 configured as described above, the yarn is conveyed to the plurality of flat knitting machines 100 by the yarn conveyor 30, and the yarns can be exchanged by the yarn exchanger 40.
Next, yarn conveyance instruction control will be described with reference to Fig. 4. In the yarn conveyance instruction control illustrated in Fig. 4, the controller 50 performs control of instructing the yarn conveyor 30 to prepare and execute the yarn conveyance. The yarn conveyance instruction control illustrated in Fig. 4 is started by operation of an operator, and the like, and is started again when YES is determined in step S21 to be described later in second and subsequent rounds. Hereinafter, the yarn cone 141 may be simply referred to as "yarn".
First, in step S10, the controller 50 determines whether all the flat knitting machines 100 are in a pause. Specifically, the controller 50 acquires operation information indicating whether the flat knitting machine 100 is in operation from each flat knitting machine 100. Based on the operation information of each flat knitting machine 100, the controller 50 determines whether all the flat knitting machines 100 are in a pause or in operation. "The flat knitting machine 100 is in operation" refers to a state in which a power supply of the flat knitting machine 100 is turned on. "The flat knitting machine 100 is in a pause" refers to a state in which the power supply of the flat knitting machine 100 is turned off. Further, even in operation, the flat knitting machine 100 may be performing the knitting, or the flat knitting machine 100 may not be performing the knitting, for example, from an end of the knitting of the knitted fabric K until a start of the knitting of the next knitted fabric K. Hereinafter, of "in operation", time when the flat knitting machine 100 is performing the knitting of the knitted fabric K is referred to as "the flat knitting machine 100 is knitting", and time when the flat knitting machine 100 is not knitting the knitted fabric K is referred to as "the flat knitting machine 100 is stopped".
Upon determination that all the flat knitting machines 100 are in a pause ("YES" in step S10), the controller 50 ends the yarn conveyance instruction control illustrated in Fig. 4. On the other hand, upon determination that not all the flat knitting machines 100 are in a pause (the flat knitting machine 100 in operation exists) ("NO" in step S10), the controller 50 proceeds to step S11.
In step S11, the controller 50 acquires various information. Specifically, the controller 50 acquires the yarn remaining amount of each yarn cone 141 set in each operating flat knitting machine 100. The yarn remaining amount is detected by the yarn remaining amount detector 10. The controller 50 acquires the knitting data used for the knitting of the knitted fabric K in the flat knitting machine 100 in operation from the storage 20. The controller 50 acquires information such as a progress status of the knitting from each flat knitting machine 100.
After performing the processing of step S11, the controller 50 proceeds to step S12.
In step S12, the controller 50 determines whether the yarn cone 141 having the yarn remaining amount of "small", "slight", or "exhausted". Specifically, the controller 50 determines to which stage among a plurality of stages set in advance the yarn remaining amount (the yarn remaining amount of the yarn cone 141 set in the flat knitting machine 100 in operation) acquired in step S11 corresponds. In this embodiment, the yarn remaining amount is classified into four stages of "large", "small", "slight", and "exhausted" based on a predetermined standard. The stages are set such that the yarn remaining amount increases in the order of "large", "small", "slight", and "exhausted". The "exhausted" is a case where the yarn remaining amount is 0. Then, the controller 50 determines whether a current yarn remaining amount of the yarn cone 141 of the flat knitting machine 100 in operation corresponds to "large", "small", "slight", or "exhausted".
Upon determination that the yarn cone 141 having the yarn remaining amount of "small", "slight", or "exhausted" exists ("YES" in step S12), the controller 50 proceeds to step S15. On the other hand, upon determination that the yarn cone 141 having the yarn remaining amount of "small", "slight", or "exhausted" does not exist (the yarn remaining amounts of all the yarn cones 141 set in the flat knitting machine 100 in operation correspond to "large") ("NO" in step S12), the controller 50 proceeds to step S13.
In step S13, the controller 50 determines whether the yarn remaining amount is insufficient for a current product. That is, the controller 50 determines presence or absence of a yarn that cannot complete knitting the current product with the current yarn remaining amount. The "current product" refers to the knitted fabric K currently being knitted. In this step, specifically, upon determination of presence of the yarn cone 141 set in the flat knitting machine 100 in operation and having the current yarn remaining amount smaller than an amount of the knitting yarn Y necessary for completing knitting the current product based on the various information acquired in step S11, the controller 50 determines presence of a yarn having the yarn remaining amount insufficient for the current product. On the other hand, upon determination of absence of the yarn cone 141 having the current yarn remaining amount smaller than the amount of the knitting yarn Y necessary for completing knitting the current product, the controller 50 determines absence of a yarn having the yarn remaining amount insufficient for the current product (determines that the yarn remaining amounts of all the yarn cones 141 are sufficient for completing knitting the current product).
Upon determination of presence of a yarn having the yarn remaining amount insufficient for the current product ("YES" in step S13), the controller 50 proceeds to step S15. On the other hand, upon determination of absence of a yarn having the yarn remaining amount insufficient for the current product ("NO" in step S13), the controller 50 proceeds to step S14.
In step S14, the controller 50 determines whether the yarn remaining amount is insufficient for a next product. That is, the controller 50 determines presence or absence of a yarn that cannot complete knitting the next product with the current yarn remaining amount. Here, the "next product" refers to the knitted fabric K to be knitted subsequently to the current product. In this step, specifically, upon determination of presence of the yarn cone 141 set in the flat knitting machine 100 in operation and having the current yarn remaining amount smaller than an amount of the knitting yarn Y necessary for completing knitting the current product and the next product based on the various information acquired in step S11, the controller 50 determines presence of a yarn having the yarn remaining amount insufficient for the next product. On the other hand, upon determination of absence of the yarn cone 141 having the current yarn remaining amount smaller than the amount of the knitting yarn Y necessary for completing knitting the current product and the next product, the controller 50 determines absence of a yarn having the yarn remaining amount insufficient for the next product.
Upon determination of presence of a yarn having the yarn remaining amount insufficient for the next product ("YES" in step S14), the controller 50 proceeds to step S15. On the other hand, upon determination of absence of the yarn having the yarn remaining amount insufficient for the next product ("NO" in step S14), the controller 50 ends the yarn conveyance instruction control illustrated in Fig. 4.
In this way, when the yarn cone 141 set in the flat knitting machine 100 in operation satisfies a predetermined condition (YES in step S12, step S13 or step S14), the controller 50 determines that the yarn conveyance is needed, and proceeds to step S15 and subsequent steps. Hereinafter, the predetermined condition for determining that the yarn conveyance is needed is referred to as yarn conveyance condition.
In step S15, the controller 50 determines whether the yarn conveyance has been prepared. Specifically, when a yarn conveyance preparation instruction (see step S18) to be described later has been transmitted to the yarn conveyor 30 with respect to the yarn cone 141 satisfying the yarn conveyance condition, the controller 50 determines that the yarn conveyance preparation instruction has been issued. On the other hand, when the yarn conveyance preparation instruction to be described later has not been transmitted to the yarn conveyor 30, the controller 50 determines that the yarn conveyance preparation instruction has not been issued.
Upon determination that the yarn conveyance has been prepared ("YES" in step S15), the controller 50 proceeds to step S19. On the other hand, upon determination that the yarn conveyance has not been prepared ("NO" in step S15), the controller 50 proceeds to step S16.
In step S16, the controller 50 determines presence or absence of a plurality of yarns satisfying the yarn conveyance condition. Specifically, the controller 50 determines presence or absence of a plurality of the yarn cones 141 satisfying the yarn conveyance condition (YES in step S12, step S13, or step S14) and having not been issued the yarn conveyance preparation instruction ("NO" in step S15).
Upon determination of presence of a plurality of yarns satisfying the yarn conveyance condition ("YES" in step S16), the controller 50 proceeds to step S17. On the other hand, upon determination of absence of a plurality of yarns (presence of one yarn) satisfying the yarn conveyance condition ("NO" in step S16), the controller 50 proceeds to step S18.
In step S17, the controller 50 performs priority order setting processing. Specifically, the controller 50 performs the processing illustrated in Fig. 8 to determine a conveyance order of the plurality of yarn cones 141 satisfying the yarn conveyance condition. That is, the controller 50 determines which yarn cone 141 is to be preferentially conveyed. Hereinafter, the priority order setting processing will be described with reference to Fig. 8.
In step S70 illustrated in Fig. 8, the controller 50 sets a priority order in ascending order of the yarn remaining amount. Specifically, the controller 50 sets the priority order of the plurality of yarn cones 141 satisfying the yarn conveyance condition based on the yarn remaining amount acquired in step S11 such that the yarn cone 141 having a smaller yarn remaining amount is ranked higher.
After performing the processing of step S70, the controller 50 ends the priority order setting processing illustrated in Fig. 8 and proceeds to step S18 illustrated in Fig. 4.
In step S18, the controller 50 issues the yarn conveyance preparation instruction. Specifically, the controller 50 transmits, to the yarn conveyor 30, the yarn conveyance preparation instruction prompting the yarn conveyor 30 to prepare for the yarn conveyance. When the plurality of yarn cones 141 satisfying the yarn conveyance condition exists, the controller 50 associates the priority order set in step S17 with the yarn conveyance preparation instruction, and transmits the yarn conveyance preparation instruction to the yarn conveyor 30.
After performing the processing of step S18, the controller 50 proceeds to step S19.
In step S19, the controller 50 determines presence or absence of a yarn conveyance preparation completion report. Specifically, when a yarn conveyance preparation completion report (see step S54 illustrated in Fig. 6) to be described later has been received from the yarn conveyor 30 with respect to the yarn cone 141 that has issued the yarn conveyance preparation instruction, the controller 50 determines that the yarn conveyance has been prepared. On the other hand, when the yarn conveyance preparation completion report has not been received from the yarn conveyor 30 with respect to the yarn cone 141 satisfying the yarn conveyance condition, the controller 50 determines that the yarn conveyance has not been prepared.
Upon determination of presence of the yarn conveyance preparation completion report ("YES" in step S19), the controller 50 proceeds to step S20. On the other hand, upon determination of absence of the yarn conveyance preparation completion report ("NO" in step S19), the controller 50 again performs the processing of step S19 (does not perform the processing until "YES" in step S19).
In step S20, the controller 50 issues a yarn conveyance execution instruction. Specifically, the controller 50 transmits, to the yarn conveyor 30, the yarn conveyance execution instruction prompting the yarn conveyor 30 to execute the yarn conveyance.
After performing the processing of step S20, the controller 50 proceeds to step S21.
In step S21, the controller 50 determines presence or absence of all the yarn conveyance completion reports. As will be described later, the yarn conveyance completion report (see step S59 illustrated in Fig. 6) is individually issued for each yarn cone 141. Upon receipt of the yarn conveyance completion reports from the yarn conveyor 30 with respect to all the yarn cones 141 for which the yarn conveyance execution instruction has been issued, the controller 50 determines presence of all the yarn conveyance completion reports. On the other hand, when the yarn conveyance completion reports have not been received with respect to all the yarn cones 141 from the yarn conveyor 30 (the yarn cone 141 that has not received the yarn conveyance completion report exists), the controller 50 determines absence of all the yarn conveyance completion reports.
Upon determination of absence of the yarn conveyance completion report ("NO" in step S21), the controller 50 again performs the processing of step S21. On the other hand, upon determination of presence of the yarn conveyance completion report ("YES" in step S21), the controller 50 ends the yarn conveyance instruction control illustrated in Fig. 4.
The yarn conveyance preparation instruction (step S18) and the yarn conveyance execution instruction (step S20) are reset at time of receipt of the yarn conveyance completion report (see step S59 illustrated in Fig 6) to be described later from the yarn conveyor 30 with respect to all the yarn cones 141 for which the yarn conveyance execution instruction has been issued.
Next, yarn exchange instruction control will be described with reference to Fig. 5. In the yarn exchange instruction control illustrated in Fig. 5, the controller 50 performs control of instructing the yarn exchanger 40 to prepare and execute the yarn exchange. The yarn exchange instruction control illustrated in Fig. 5 is executed for each yarn cone 141. The yarn exchange instruction control illustrated in Fig. 5 is executed after the yarn conveyance of each yarn cone 141 is completed.
First, in step S30, the controller 50 determines presence of the yarn conveyance completion report. Specifically, when the yarn conveyance completion report (step S59 illustrated in Fig. 6) to be described later has been received from the yarn conveyor 30, the controller 50 determines presence of the yarn conveyance completion report. On the other hand, when the yarn conveyance completion report to be described later is not received from the yarn conveyor 30, the controller 50 determines absence of the yarn conveyance completion report.
Upon determination of presence of the yarn conveyance completion report ("YES" in step S30), the controller 50 proceeds to step S31. On the other hand, upon determination of absence of the yarn conveyance completion report ("NO" in step S30), the controller 50 ends the yarn exchange instruction control illustrated in Fig. 5.
In step S31, the controller 50 determines whether a yarn exchange preparation instruction has been issued. Specifically, when the yarn exchange preparation instruction (see steps S33 and S40) to be described later has been transmitted to the yarn exchanger 40 with respect to the yarn cone 141 for which the yarn conveyance completion report has been received, the controller 50 determines that the yarn exchange preparation instruction has been issued. On the other hand, when the yarn exchange preparation instruction to be described later has not been transmitted to the yarn exchanger 40 with respect to the yarn cone 141 for which the yarn conveyance completion report has been issued, the controller 50 determines that the yarn exchange preparation instruction has not been issued.
Upon determination that the yarn exchange instruction has been issued ("YES" in step S31), the controller 50 proceeds to step S46. On the other hand, upon determination that the yarn exchange instruction has not been issued ("NO" in step S31), the controller 50 proceeds to step S32.
In step S32, the controller 50 determines whether the yarn remaining amount is insufficient for the current product. That is, the controller 50 determines presence or absence of a yarn that cannot complete knitting the current product with the current yarn remaining amount. Specifically, the controller 50 determines that the yarn remaining amount is insufficient for the current product upon determination that the current yarn remaining amount of the yarn cone 141 set in the flat knitting machine 100 corresponding to the yarn cone 141 already conveyed is smaller than the amount of the knitting yarn Y necessary for completing knitting the current product. On the other hand, upon determination that the current yarn remaining amount is greater than or equal to the amount of the knitting yarn Y necessary for completing knitting the current product, the controller 50 determines that the yarn remaining amount is not insufficient for the current product (the yarn remaining amount of the yarn cone 141 is sufficient for completing knitting the current product).
Upon determination that the yarn remaining amount is insufficient for the current product ("YES" in step S32), the controller 50 proceeds to step S33. On the other hand, upon determination that the yarn remaining amount is not insufficient for the current product ("NO" in step S32), the controller 50 proceeds to step S38.
In step S38, the controller 50 determines whether the yarn remaining amount is insufficient for the next product. That is, the controller 50 determines presence or absence of a yarn that cannot complete knitting the next product with the current yarn remaining amount. Specifically, upon determination that the current yarn remaining amount is smaller than the amount of the knitting yarn Y necessary for completing knitting the current product and the next product, the controller 50 determines that the yarn remaining amount is insufficient for the next product. On the other hand, upon determination that the current yarn remaining amount is greater than or equal to the amount of the knitting yarn Y necessary for completing knitting the current product and the next product, the controller 50 determines that the yarn remaining amount is not insufficient for the next product.
Upon determination that the yarn remaining amount is insufficient for the next product ("YES" in step S38), the controller 50 proceeds to step S39. On the other hand, upon determination that the yarn remaining amount is not insufficient for the next product ("NO" in step S38), the controller 50 ends the yarn exchange instruction control illustrated in Fig. 5.
In this way, when the yarn cone 141 set in the flat knitting machine 100 in operation satisfies a predetermined condition (the yarn conveyance condition is satisfied and YES in step S32 or S38), the controller 50 determines that the yarn exchange is necessary, and proceeds to the subsequent step. Hereinafter, the predetermined condition for determining that the yarn exchange is necessary is referred to as yarn exchange condition.
In step S33, the controller 50 issues the yarn exchange preparation instruction. Specifically, the controller 50 transmits, to the yarn exchanger 40, the yarn exchange preparation instruction prompting the yarn exchanger 40 to prepare for the yarn exchange.
After performing the processing of step S33, the controller 50 proceeds to step S34.
In step S34, the controller 50 determines presence or absence of the yarn exchange preparation completion report. Specifically, the controller 50 determines that the yarn exchange has been prepared when the yarn exchange preparation completion report (see step S64 illustrated in Fig. 7) to be described later has been received from the yarn exchanger 40 with respect to the yarn cone 141 that has issued the yarn exchange preparation instruction. On the other hand, when the yarn exchange preparation completion report to be described later has not been received from the yarn conveyor 30, the controller 50 determines that the yarn exchange has not been prepared.
Upon determination of presence of the yarn exchange preparation completion report ("YES" in step S34), the controller 50 proceeds to step S35. On the other hand, upon determination of absence of the yarn exchange preparation completion report ("NO" in step S34), the controller 50 again performs the processing of step S34.
In step S35, the controller 50 determines whether the flat knitting machine 100 is knitting. Specifically, the controller 50 acquires the operation information from the flat knitting machine 100 of the yarn cone 141 for which the yarn conveyance completion report has been issued, and determines whether the flat knitting machine 100 is knitting or is stopped.
Upon determination that the flat knitting machine 100 is knitting ("YES" in step S35), the controller 50 proceeds to step S36. On the other hand, upon determination that the flat knitting machine 100 is not knitting (the flat knitting machine 100 is stopped) ("NO" in step S35), the controller 50 proceeds to step S37.
In step S36, the controller 50 determines whether the yarn carrier 131 is in operation. Specifically, the controller 50 determines whether the yarn carrier 131 configured to feed the knitting yarn Y of the yarn cone 141 satisfying the yarn exchange condition is in operation for the knitting of the knitted fabric K. That is, the controller 50 determines whether the knitting yarn Y of the yarn cone 141 satisfying the yarn exchange condition is being used for the knitting of the knitted fabric K.
Upon determination that the yarn carrier 131 is in operation ("YES" in step S36), the controller 50 returns the processing to step S35. On the other hand, upon determination that the yarn carrier 131 is not in operation ("NO" in step S36), the controller 50 proceeds to step S37.
In step S37, the controller 50 determines whether time until a start of use of the carrier is equal to or more than α minutes. Here, "α minutes" indicates a time required for the yarn exchange.
Upon determination that the time until the start of use of the carrier is α minutes or more ("YES" in step S37), the controller 50 proceeds to step S45. On the other hand, upon determination that the time until the start of use of the carrier is not equal to or more than α minutes ("NO" in step S37), the controller 50 returns the processing to step S35.
On the other hand, in step S39, the controller 50 determines whether remaining knitting time is less than 10 minutes. Specifically, the controller 50 determines whether the remaining knitting time is less than 10 minutes based on the knitting data and progress information of the knitting of the flat knitting machine 100. The "remaining knitting time" refers to time from current time to an end of the knitting of the knitted fabric K currently being knitted.
Upon determination that the remaining knitting time is less than 10 minutes ("YES" in step S39), the controller 50 proceeds to step S40. On the other hand, upon determination that the remaining knitting time is not less than 10 minutes ("NO" in step S39), the controller 50 performs the processing of step S39 again.
In step S40, the controller 50 issues the yarn exchange preparation instruction. Specifically, the controller 50 transmits, to the yarn exchanger 40, the yarn exchange preparation instruction prompting the yarn exchanger 40 to prepare for the yarn exchange.
After performing the processing of step S40, the controller 50 proceeds to step S41.
In step S41, the controller 50 determines presence or absence of the yarn exchange preparation completion report. Specifically, the controller 50 determines that the yarn exchange has been prepared when the yarn exchange preparation completion report (see step S64 illustrated in Fig. 7) to be described later has been received from the yarn exchanger 40 with respect to the yarn cone 141 that has issued the yarn exchange preparation instruction. On the other hand, when the yarn exchange preparation completion report to be described later has not been received from the yarn exchanger 40, the controller 50 determines that the yarn exchange has not been prepared.
Upon determination of presence of the yarn exchange preparation completion report ("YES" in step S41), the controller 50 proceeds to step S42. On the other hand, upon determination of absence of the yarn exchange preparation completion report ("NO" in step S41), the controller 50 again performs the processing of step S41.
In step S42, the controller 50 determines whether the knitting of the current product is finished. Specifically, the controller 50 determines whether the knitting of the current product is finished in the flat knitting machine 100 that has issued the yarn exchange preparation instruction and the flat knitting machine 100 is stopped.
Upon determination that the knitting of the current product is finished ("YES" in step S42), the controller 50 proceeds to step S43. On the other hand, upon determination that the knitting of the current product is not finished ("NO" in step S42), the controller 50 performs the processing of step S42 again.
In step S43, the controller 50 determines whether the knitting will be completed until the next carrier stop after the start of the knitting of the next product. Specifically, the controller 50 calculates an amount (required yarn amount) of the knitting yarn Y required until the yarn carrier 131 first stops at the time of knitting the next product based on the knitting data stored in the storage 20 with respect to the yarn cone 141 that has received the yarn exchange preparation completion report. Then, the controller 50 determines that the knitting until the next carrier stop will be completed when the yarn remaining amount is greater than the required yarn amount or is equal to the required yarn amount based on the yarn remaining amount at the time of completing the knitting of the current product. On the other hand, when the yarn remaining amount at the time of completing the knitting of the current product is smaller than the required yarn amount, the controller 50 determines that the knitting until the next carrier stop will not be completed.
Upon determination that the knitting will be completed until the next carrier stop ("YES" in step S43), the controller 50 proceeds to step S44. On the other hand, upon determination that the knitting will not be completed until the next carrier stop ("NO" in step S43), the controller 50 proceeds to step S45.
In step S44, the controller 50 determines whether the carrier is stopped immediately before the yarn exhaustion. Specifically, the controller 50 calculates how far the next product can be knitted (where the yarn will be exhausted) with respect to the yarn cone 141 that has received the yarn exchange preparation completion report. Then, the controller 50 determines whether the carrier stop is at a timing at which the yarn carrier 131 stops immediately before the yarn exhaustion among a plurality of timings at which the yarn carrier 131 stops.
Upon determination that the carrier stop is immediately before the yarn exhaustion ("YES" in step S44), the controller 50 proceeds to step S45. On the other hand, upon determination that the carrier stop is not immediately before the yarn exhaustion ("NO" in step S44), the controller 50 again performs the processing of step S44.
In step S45, the controller 50 issues the yarn exchange execution instruction. Specifically, the controller 50 transmits, to the yarn exchanger 40, the yarn exchange execution instruction prompting the yarn exchanger 40 to execute the yarn exchange.
After performing the processing of step S45, the controller 50 proceeds to step S46.
In step S46, the controller 50 determines presence or absence of the yarn exchange completion report. Specifically, the controller 50 determines whether the yarn exchange completion report (see step S69 illustrated in Fig. 7) to be described later has been received from the yarn exchanger 40 with respect to the yarn cone 141 that has issued the yarn exchange execution instruction.
Upon determination of absence of the yarn exchange completion report ("NO" in step S46), the controller 50 again performs the processing of step S46. On the other hand, upon determination of presence of the yarn exchange completion report ("YES" in step S46), the controller 50 ends the yarn exchange instruction control illustrated in Fig. 5.
The yarn exchange preparation instruction (steps S33 and S40) and the yarn exchange execution instruction (step S46) are reset at time of receipt the yarn exchange completion report (see step S69 illustrated in Fig. 7) to be described later from the yarn exchanger 40.
Next, yarn conveyance processing will be described with reference to Fig. 6. The yarn conveyance processing illustrated in Fig. 6 is performed by the controller of the yarn conveyor 30 based on the yarn conveyance preparation instruction (step S18 illustrated in Fig. 4) and the yarn conveyance execution instruction (step S20 illustrated in Fig. 4) transmitted from the controller 50.
In step S50, the yarn conveyor 30 determines presence or absence of the yarn conveyance preparation instruction. Specifically, when having received yarn conveyance preparation instruction (step S18 illustrated in Fig. 4) from the controller 50, the yarn conveyor 30 determines presence of the yarn conveyance preparation instruction. On the other hand, when not having received the yarn conveyance preparation instruction from the controller 50, the yarn conveyor 30 determines absence of the yarn conveyance preparation instruction.
Upon determination of presence of the yarn conveyance preparation instruction ("YES" in step S50), the yarn conveyor 30 proceeds to step S51. On the other hand, upon determination of absence of the yarn conveyance preparation instruction ("NO" in step S50), the yarn conveyor 30 ends the yarn conveyance processing illustrated in Fig. 6.
In step S51, the yarn conveyor 30 performs the yarn conveyance preparation. Specifically, the yarn conveyor 30 travels on a predetermined travelling path, and prepares for performing the yarn conveyance such as picking up the new yarn cone 141 from the storage location.
When having received a plurality of the yarn conveyance preparation instructions from the controller 50, the yarn conveyor 30 performs the yarn conveyance preparation with respect to all the yarn cones 141 for which the yarn conveyance preparation instructions have been issued.
After performing the processing of step S51, the yarn conveyor 30 proceeds to step S52.
In step S52, the yarn conveyor 30 determines whether the yarn conveyance preparation is in progress. Specifically, when the yarn conveyance preparation has already been started, the yarn conveyor 30 determines that the yarn conveyance preparation is in progress. On the other hand, when the yarn conveyance preparation has not been started yet, the yarn conveyor 30 determines that the yarn conveyance preparation is not in progress.
Upon determination that the yarn conveyance preparation is in progress ("YES" in step S52), the yarn conveyor 30 proceeds to step S53. On the other hand, upon determination that the yarn conveyance is not in progress ("NO" in step S52), the yarn conveyor 30 again performs the processing of step S52.
In step S53, the yarn conveyor 30 determines whether the yarn conveyance preparation is completed. Specifically, the yarn conveyor 30 determines that the yarn conveyance preparation is completed when the yarn conveyance preparation of all the yarn cones 141 for which the yarn conveyance preparation instruction has been issued is completed. On the other hand, when the yarn conveyance preparation of all the yarn cones 141 for which the yarn conveyance preparation instruction has been issued is not completed (the yarn cone 141 for which the yarn conveyance preparation is not completed exists), the yarn conveyor 30 determines that the yarn conveyance preparation is not completed.
Upon determination that the yarn conveyance preparation is completed ("YES" in step S53), the yarn conveyor 30 proceeds to step S54. On the other hand, upon determination that the yarn conveyance preparation is not completed ("NO" in step S53), the yarn conveyor 30 again performs the processing of step S53.
In step S54, the yarn conveyor 30 issues the yarn conveyance preparation completion report. Specifically, the yarn conveyor 30 transmits, to the controller 50, the yarn conveyance preparation completion report as a report indicating that the yarn conveyance preparation is completed.
After performing the processing of step S54, the yarn conveyor 30 proceeds to step S55.
In step S55, the yarn conveyor 30 determines presence or absence of the yarn conveyance execution instruction. Specifically, when having received the yarn conveyance execution instruction (step S20 illustrated in Fig. 4) from the controller 50, the yarn conveyor 30 determines presence of the yarn conveyance execution instruction. On the other hand, when not having received the yarn conveyance execution instruction from the controller 50, the yarn conveyor 30 determines absence of the yarn conveyance execution instruction.
Upon determination of presence of the yarn conveyance execution instruction ("YES" in step S55), the yarn conveyor 30 proceeds to step S56. On the other hand, upon determination of absence of the yarn conveyance execution instruction ("NO" in step S55), the yarn conveyor 30 again performs the processing of step S55.
In step S56, the yarn conveyor 30 executes the yarn conveyance. Specifically, the yarn conveyor 30 travels on a predetermined travelling path, and conveys the new yarn cone 141 picked up to the target flat knitting machine 100.
When having received a plurality of the yarn conveyance execution instructions from the controller 50, the yarn conveyor 30 sequentially executes the yarn conveyance in accordance with the priority order set in step S17 illustrated in Fig. 4.
After performing the processing of step S56, the yarn conveyor 30 proceeds to step S57.
In step S57, the yarn conveyor 30 determines whether the yarn conveyance is in progress. Specifically, the yarn conveyor 30 determines that the yarn conveyance is in progress when the yarn conveyance is being executed. On the other hand, the yarn conveyor 30 determines that the yarn conveyance is not in progress when the yarn conveyance is not being executed.
Upon determination that the yarn conveyance is in progress ("YES" in step S57), the yarn conveyor 30 proceeds to step S58. On the other hand, upon determination that the yarn conveyance is not in progress ("NO" in step S57), the yarn conveyor 30 again performs the processing of step S57.
In step S58, the yarn conveyor 30 determines whether the yarn conveyance is completed. Specifically, the yarn conveyor 30 determines that the yarn conveyance is completed when the yarn conveyance of all the yarn cones 141 for which the yarn conveyance execution instruction has been issued is completed. On the other hand, when the yarn conveyance of all the yarn cones 141 for which the yarn conveyance execution instruction has been issued is not completed (the yarn cone 141 for which the yarn conveyance is not completed exists), the yarn conveyor 30 determines that the yarn conveyance is not completed.
Upon determination that the yarn conveyance is completed ("YES" in step S58), the yarn conveyor 30 proceeds to step S59. Upon determination that the yarn conveyance is not completed ("NO" in step S58), the yarn conveyor 30 again performs the processing of step S58.
In step S59, the yarn conveyor 30 issues the yarn conveyance completion report. Specifically, the yarn conveyor 30 transmits, to the controller 50, the yarn conveyance completion report as a report indicating that the yarn conveyance is completed. The yarn conveyance completion report is individually issued for each yarn cone 141.
After performing the processing of step S59, the yarn conveyor 30 ends the yarn conveyance processing illustrated in Fig. 6.
Next, yarn exchange processing will be described with reference to Fig. 7. The yarn exchange processing illustrated in Fig. 7 is performed by each controller of the yarn exchanger 40 provided in each flat knitting machine 100 based on the yarn exchange preparation instruction (steps S33 and S40 illustrated in Fig. 5) and the yarn exchange execution instruction (step S45 illustrated in Fig. 5) transmitted from the controller 50. The yarn exchange processing illustrated in Fig. 7 is executed for each yarn cone 141.
In step S60, the yarn exchanger 40 determines whether presence of the yarn exchange preparation instruction. Specifically, when having received the yarn exchange preparation instruction (steps S33 and S40 illustrated in Fig. 5) from the controller 50, the yarn exchanger 40 determines presence of the yarn exchange preparation instruction. When not having received the yarn exchange preparation instruction from the controller 50, the yarn exchanger 40 determines absence of the yarn exchange preparation instruction.
Upon determination of presence of the yarn exchange preparation instruction ("YES" in step S60), the yarn exchanger 40 proceeds to step S61. On the other hand, upon determination of absence the yarn exchange preparation instruction ("NO" in step S60), the yarn exchanger 40 ends the yarn exchange processing illustrated in Fig. 7.
In step S61, the yarn exchanger 40 performs the yarn exchange preparation.
After performing the processing of step S61, the yarn exchanger 40 proceeds to step S62.
In step S62, the yarn exchanger 40 determines whether the yarn exchange preparation is in progress. Specifically, when the yarn exchange preparation has already been started, the yarn exchanger 40 determines that the yarn exchange preparation is in progress. On the other hand, when the yarn exchange preparation has not been started yet, the yarn exchanger 40 determines that the yarn exchange preparation is not in progress.
Upon determination that the yarn exchange preparation is in progress ("YES" in step S62), the yarn exchanger 40 proceeds to step S63. On the other hand, upon determination that the yarn exchange preparation is not in progress ("NO" in step S62), the yarn exchanger 40 again performs the processing of step S62.
In step S63, the yarn exchanger 40 determines whether the yarn exchange preparation is completed.
Upon determination that the yarn exchange preparation is completed ("YES" in step S63), the yarn exchanger 40 proceeds to step S64. On the other hand, upon determination that the yarn exchange preparation is not completed ("NO" in step S63), the yarn exchanger 40 again performs the processing of step S63.
In step S64, the yarn exchanger 40 issues the yarn exchange preparation completion report. Specifically, the yarn exchanger 40 transmits, to the controller 50, the yarn exchange preparation completion report as a report indicating that the yarn exchange preparation is completed.
After performing the processing of step S64, the yarn exchanger 40 proceeds to step S65.
In step S65, the yarn exchanger 40 determines presence or absence of the yarn exchange execution instruction. Specifically, when having received the yarn exchange execution instruction (step S45 illustrated in Fig. 5) from the controller 50, the yarn exchanger 40 determines presence of the yarn exchange execution instruction. On the other hand, when not having received the yarn exchange execution instruction from the controller 50, the yarn exchanger 40 determines absence of the yarn exchange execution instruction.
Upon determination of presence of the yarn exchange execution instruction ("YES" in step S65), the yarn exchanger 40 proceeds to step S66. On the other hand, upon determination of absence of the yarn exchange execution instruction ("NO" in step S65), the yarn exchanger 40 again performs the processing of step S65.
In step S66, the yarn exchanger 40 executes the yarn exchange.
After performing the processing of step S66, the yarn exchanger 40 proceeds to step S67.
In step S67, the yarn exchanger 40 determines whether the yarn exchange is in progress. Specifically, when the yarn exchange is being executed, the yarn exchanger 40 determines that the yarn exchange is in progress. On the other hand, when the yarn exchange is not being executed, the yarn exchanger 40 determines that the yarn exchange is not in progress.
Upon determination that the yarn exchange is in progress ("YES" in step S67), the yarn exchanger 40 proceeds to step S68. On the other hand, upon determination that the yarn exchange is not in progress ("NO" in step S67), the yarn exchanger 40 again performs the processing of step S67.
In step S68, the yarn exchanger 40 determines whether the yarn exchange is completed.
Upon determination that the yarn exchange is completed ("YES" in step S68), the yarn exchanger 40 proceeds to step S69. On the other hand, upon determination that the yarn exchange is not completed ("NO" in step S68), the yarn exchanger 40 again performs the processing of step S68.
In step S69, the yarn exchanger 40 issues the yarn exchange completion report. Specifically, the yarn exchanger 40 transmits, to the controller 50, the yarn exchange completion report as a report indicating that the yarn exchange is completed.
After performing the processing of step S69, the yarn exchanger 40 ends the yarn exchange processing illustrated in Fig. 7.
Specific examples of the yarn conveyance and the yarn exchange will be described below with reference to Fig. 9. Fig. 9 illustrates a state of the yarn remaining amount and the like of each flat knitting machine 100, and presence or absence of necessity of the yarn exchange and the yarn conveyance of each flat knitting machine 100. In the examples illustrated in Fig. 9, the yarn conveyance and the yarn exchange are performed for three flat knitting machines 100 (flat knitting machine 100A, flat knitting machine 100B, and flat knitting machine 100C). The flat knitting machine 100A uses a knitting yarn YA of a yarn cone 141A, the flat knitting machine 100B uses a knitting yarn YB of a yarn cone 141B, and the flat knitting machine 100C uses a knitting yarn YC of a yarn cone 141C for the knitting. In practice, each flat knitting machine 100 is provided with the plurality of yarn cones 141, and the knitting yarn Y of the plurality of yarn cones 141 is used for the knitting, but for simplification of description, only a state of one yarn cone 141 is illustrated in Fig. 9.
As illustrated in Fig. 9, in the flat knitting machine 100A, the yarn cone 141A satisfies the yarn conveyance condition since the yarn remaining amount corresponds to "slight" (YES in step S12 illustrated in Fig. 4). The yarn cone 141A satisfies the yarn conveyance condition, and satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the current product (YES in step S32 illustrated in Fig. 5).
In the flat knitting machine 100B, the yarn remaining amount of the yarn cone 141B corresponds to "large" (NO in step S12 illustrated in Fig. 4), is sufficient for the current product and the next product (NO in steps S13 and S14 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition. Further, the yarn cone 141A does not satisfy the yarn conveyance condition, and thus the yarn cone does not satisfy the yarn exchange condition.
In the flat knitting machine 100C, the yarn remaining amount of the yarn cone 141C corresponds to "small" (YES in step S12 illustrated in Fig. 4), and thus satisfies the yarn conveyance condition. The yarn cone 141C satisfies the yarn conveyance condition, and also satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the next product (YES in step S38 illustrated in Fig. 5).
In this way, since the yarn cone 141 satisfying the yarn conveyance condition exists in the plurality of flat knitting machines 100 (YES in step S16 illustrated in Fig. 4), the priority order setting processing (step S17 illustrated in Fig. 4) is performed.
As described above, the yarn remaining amount of the yarn cone 141A of the flat knitting machine 100A corresponds to "slightly", and the yarn remaining amount of the yarn cone 141C of the flat knitting machine 100C corresponds to "small". Thus, of the yarn cone 141A and the yarn cone 141C, the yarn remaining amount of the yarn cone 141A is smaller than the yarn remaining amount of the yarn cone 141C. Therefore, the controller 50 sets the priority order such that the yarn cone 141A is ranked first and the yarn cone 141C is ranked second (such that the yarn cone 141A is ranked higher than the yarn cone 141C) (step S70 illustrated in Fig. 8).
The yarn conveyor 30 first performs the yarn conveyance preparation (step S51 illustrated in Fig. 6) of the yarn cones 141A and 141C. Upon completion of the yarn conveyance preparation of the yarn cone 141A and the yarn cone 141C (YES in step S53 illustrated in Fig. 6), the yarn conveyor 30 issues the yarn conveyance preparation completion report to the controller 50 (step S54 illustrated in Fig. 6).
Upon receipt of the yarn conveyance preparation completion report, the controller 50 issues, to the yarn conveyor 30, the yarn conveyance execution instruction of the yarn cone 141A and the yarn cone 141C (step S20 illustrated in Fig. 4). Upon receipt of the yarn conveyance execution instruction (YES in step S55 illustrated in Fig. 6), the yarn conveyor 30 first conveys the yarn cone 141A ranked higher in the priority order to the flat knitting machine 100A. Upon completion of the conveyance of the yarn cone 141A to the flat knitting machine 100A, the yarn conveyor 30 conveys the yarn cone 141C to the flat knitting machine 100C.
In this way, the new yarn cones 141A and the yarn cones 141C are conveyed to the flat knitting machine 100A and the flat knitting machine 100C, and the yarn conveyance is completed (YES in step S59 illustrated in Fig. 6 and step S21 illustrated in Fig. 4). Then, the yarn conveyance instruction control (Fig. 4) by the controller 50 and the yarn conveyance processing (Fig. 6) by the yarn conveyor 30 end.
Upon receipt of the yarn conveyance completion report of the yarn cone 141A (YES in step S30 illustrated in Fig 5), the controller 50 determines whether the yarn remaining amount of the yarn cone 141A is insufficient for the current product (step S32 illustrated in Fig. 5). Since the yarn remaining amount of the yarn cone 141A is insufficient for the current product (YES in step S32 illustrated in Fig. 5), the controller 50 issues the yarn exchange preparation instruction to the yarn exchanger 40A provided in the flat knitting machine 100A (step S33 illustrated in Fig. 5). Upon receipt of the yarn conveyance completion report of the yarn cone 141C (YES in step S30 illustrated in Fig 5), the controller 50 determines whether the yarn remaining amount of the yarn cone 141C is insufficient for the current product (step S32 illustrated in Fig. 5). The yarn remaining amount of the yarn cone 141C is insufficient for the next product (YES in step S38 illustrated in Fig. 5), and thus the controller 50 waits for the remaining knitting time to become less than 10 minutes and issues the yarn exchange preparation instruction to the yarn exchanger 40C (steps S39 and S40 illustrated in Fig. 5).
First, the yarn exchange of the flat knitting machine 100A will be described below.
Upon receipt of the yarn exchange preparation instruction from the controller 50 (YES in step S60 illustrated in Fig. 7), the yarn exchanger 40A performs the yarn exchange preparation (step S61 illustrated in Fig. 7). Upon completion of the yarn exchange preparation, the yarn exchanger 40A transmits the yarn exchange preparation completion report to the controller 50 (YES in step S63 illustrated in Fig. 7, step S64).
The controller 50 receives the yarn exchange preparation completion report from the yarn exchanger 40A (YES in step S34 illustrated in Fig. 5). Since a knitting status of a yarn cone 141A1 (yarn carrier 131 of the knitting yarn YA) is stopped (NO in step S36 illustrated in Fig. 5), in a case where the time required for the yarn exchange will be in time for next operation of the yarn carrier 131 (after 10 minutes) (YES in step S37 illustrated in Fig. 5), the controller 50 issues the yarn exchange execution instruction to the yarn exchanger 40A of the flat knitting machine 100A (step S45 illustrated in Fig. 5).
Upon receipt of the yarn exchange execution instruction from the controller 50 (YES in step S65 illustrated in Fig. 7), the yarn exchanger 40A executes the yarn exchange of the flat knitting machine 100A (step S66 illustrated in Fig. 7).
In this way, the yarn exchange of the flat knitting machine 100A is completed (YES in step S69 illustrated in Fig. 7 and step S21 illustrated in Fig. 5), and the yarn exchange instruction control by the controller 50 (Fig. 5) and the yarn exchange processing by the yarn exchanger 40A (Fig. 7) end.
Next, the yarn exchange of the flat knitting machine 100C will be described.
Upon receipt of the yarn exchange preparation instruction from the controller 50 (YES in step S60 illustrated in Fig. 7), the yarn exchanger 40C of the flat knitting machine 100C performs the yarn exchange preparation (step S61 illustrated in Fig. 7). Upon completion of the yarn exchange preparation, the yarn exchanger 40C transmits the yarn exchange preparation completion report to the controller 50 (YES in step S63 illustrated in Fig. 7, step S64).
Upon receipt of the yarn exchange preparation completion report from the yarn exchanger 40C (YES in step S41 illustrated in Fig. 5), the controller 50 stands by until the knitting of the current product is completed (step S42 illustrated in Fig. 5). In a case where the knitting until the next carrier stop will be completed with the yarn remaining amount at the time of completing the knitting of the current product (YES in step S43 illustrated in Fig. 5), the yarn exchange execution instruction is issued to the yarn exchanger 40C at the time of carrier stop immediately before the yarn exhaustion after the start of knitting of the next product (steps S44 and S45 illustrated in Fig. 5).
Upon receipt of the yarn exchange execution instruction from the controller 50 (YES in step S65 illustrated in Fig. 7), the yarn exchanger 40C executes the yarn exchange of the flat knitting machine 100C (step S66 illustrated in Fig. 7).
In this way, the yarn exchange of the flat knitting machine 100C is completed (YES in step S69 illustrated in Fig. 7 and step S21 illustrated in Fig. 5), and the yarn exchange instruction control by the controller 50 (Fig. 5) and the yarn exchange processing by the yarn exchanger 40C (Fig. 7) end.
As described above, in the yarn management system 1, the yarn conveyor 30 and the yarn exchanger 40 are controlled by both the yarn remaining amount and the knitting data to manage the yarn. Specifically, the yarn conveyance condition (YES in steps S12, S13, and S14 illustrated in Fig. 4) is calculated based on both the yarn remaining amount and the knitting data, and the yarn conveyance is performed with respect to the yarn cone 141 satisfying the yarn conveyance condition. The yarn exchange condition (the yarn conveyance condition is satisfied, and YES in step S32 or S38 illustrated in Fig. 5) is similarly calculated based on both the yarn remaining amount and the knitting data, and the yarn exchange is performed with respect to the yarn cone 141 satisfying the yarn exchange condition. In this way, when the yarn cone 141 satisfying management conditions (yarn conveyance condition and yarn exchange condition) calculated by both the yarn remaining amount and the knitting data exist, yarn management (yarn conveyance and yarn exchange) is performed by the yarn conveyor 30 and the yarn exchanger 40, and the yarn management can be therefore optimized.
In the yarn management system 1, the yarn remaining amount of the yarn cone 141 disposed in the flat knitting machine 100 is detected by the yarn remaining amount detector 10. When the detected yarn remaining amount is less than or equal to a predetermined threshold value, specifically, when any of "small", "slight", or "exhausted" is satisfied (YES in step S12 illustrated in Fig. 4), the yarn conveyance and the yarn exchange are performed with respect to the yarn cone 141. Therefore, the flat knitting machine 100 is prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in production efficiency due to a stop of the flat knitting machine 100.
Upon determination of presence of the yarn cone 141 not allowing knitting of the current product (knitted fabric K being knitted) or the next product (knitted fabric K to be knitted next) with the current yarn remaining amount (YES in steps S13 and S14 illustrated in Fig. 4), the yarn management system 1 performs the yarn conveyance and the yarn exchange with respect to the yarn cone 141. Therefore, the flat knitting machine 100 is prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in the production efficiency.
Further, in the yarn management system 1, the yarn conveyance is performed each time the yarn cone 141 satisfying the yarn conveyance condition based on the yarn remaining amount and the like exists. This eliminates the need for providing a space for storing the new yarn cone 141 as a spare near each flat knitting machine 100. Therefore, the plurality of flat knitting machines 100 can be disposed with a relatively short distance between each other, and then a space of the arrangement location of the flat knitting machine 100 can be reduced.
Further, in the yarn management system 1, when the yarn cone 141 satisfying the yarn conveyance condition exists in the plurality of flat knitting machines 100, the yarn conveyance is preferentially performed in ascending order of the yarn remaining amount (step S17 illustrated in Fig. 4, step S70 illustrated in Fig. 8, and step S56 illustrated in Fig. 6). Therefore, the flat knitting machine 100 is prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in the production efficiency.
Further, in the yarn management system 1, the yarn exchange is performed during a period in which the knitting yarn Y is not used for the knitting (the yarn carrier 131 of the knitting yarn Y is stopped) (NO in step S36 and YES in step S42 illustrated in Fig. 5). Therefore, the yarn exchange can be performed without stopping the flat knitting machine 100.
Further, upon determination of presence of the yarn cone 141 allowing completing knitting of the current product but not allowing completing knitting of the next product with the current yarn remaining amount (YES in step S38 illustrated in Fig. 5), the yarn management system 1 calculates how far the next product can be knitted based on the yarn remaining amount and the knitting data, and determines time to exchange the yarn cone 141 in accordance with calculation results (steps S43 to S45 illustrated in Fig. 5). Thus, for example, when the yarn remaining amount does not have a margin at the time of completing the knitting of the current product (NO in step S43 illustrated in Fig. 5), the yarn exchange is performed at this point of time. On the other hand, when the yarn remaining amount has a margin (YES in step S43 illustrated in Fig. 5), the yarn exchange is performed after knitting the next product partway (YES in step S44 illustrated in Fig. 5, step S45). As a result, the knitting yarn Y wound around the yarn cone 141 can be used maximally, and a usage rate of the knitting yarn Y can be improved.
Although the embodiment of the disclosure has been described above, the disclosure is not limited to the embodiment, and appropriate modifications can be made within the technical ideas of the disclosure described in the claims.
For example, in this embodiment, the yarn management system 1 includes both the yarn conveyor 30 and the yarn exchanger 40, but only has to include at least one of the yarn conveyor 30 or the yarn exchanger 40. That is, the yarn conveyance or the yarn exchange may be manually performed by an operator.
In this embodiment, the automatic guided vehicle (AGV) is used as the yarn conveyor 30, but a belt conveyor or a hanger system may be used.
In this embodiment, each flat knitting machine 100 includes the yarn exchanger 40, but one yarn exchanger 40 may perform the yarn exchange of each flat knitting machine 100.
Further, in this embodiment, in step S12 illustrated in Fig. 4, the controller 50 determines to which of the plurality of stages ("small", "slight" or "exhausted") the yarn remaining amount corresponds. However, a threshold value may be defined for the length of the remaining yarn itself, and the determination may be made based on the threshold value. The threshold value may be determined with respect to a weight of the remaining yarn.
In this embodiment, the yarn exchange is performed at a predetermined timing (steps S42 to S45, and the like illustrated in Fig. 5) after performing the yarn conveyance, but the yarn exchange may be performed immediately after performing the yarn conveyance. Further, for example, the yarn exchanger 40 may perform the yarn exchange when the yarn remaining amount becomes less than or equal to a predetermined threshold value.
In this embodiment, the new yarn cone 141 is stored in the storage location different from the flat knitting machine 100, but a creel stand capable of storing the yarn cone 141 as a spare may be provided in the flat knitting machine 100. The creel stand is rotated to switch the yarn cone 141 having the knitting yarn Y to be fed to the flat knitting machine 100. In such a creel stand, when the yarn cone being used is used up, the yarn cone is automatically switched to the next yarn cone 141, and a stock count is subtracted by one from an initial value. In this case, the yarn exhaustion can be prevented by replenishing such that the stock count does not reach "one" as much as possible. Further, the yarn conveyor 30 may stock the new yarn cone 141 to some extent.
In this embodiment, the flat knitting machine 100 has been described as an example of the knitting machine, but the knitting machine is not limited to the flat knitting machine 100, and other knitting machines such as a warp knitting machine and a circular knitting machine may be used.
In this embodiment, the yarn exchange is performed without stopping the flat knitting machine 100, but the controller 50 may temporarily stop the flat knitting machine 100 for the yarn exchange.
In this embodiment, the yarn remaining amount is directly detected by the yarn remaining amount detector 10, but a method of detecting the yarn remaining amount is not limited to this. For example, an initial value of the yarn remaining amount of the unused yarn cone 141 may be acquired in advance in a warehouse or the like, and the yarn remaining amount may be indirectly detected by subtracting an amount consumed in the knitting from the initial value at any time.
Further, for example, when the yarn conveyance is not in time and the yarn remaining amount is likely to cause yarn exhaustion, the controller 50 may stop the flat knitting machine 100 before the yarn exhaustion occurs. As a result, the operation of passing a new yarn through the yarn feeding path of the flat knitting machine 100 can be omitted.
The knitting data may be the same between the current product and the next product, or may be different for each product. That is, the flat knitting machine 100 may repeatedly knit the same type of product, or may be able to knit different types of products.
In this embodiment, the priority order of the yarn conveyance is set in ascending order of the yarn remaining amount (step S70 illustrated in Fig. 8), but a method of setting the priority order is not limited to this. Hereinafter, a second embodiment of the method of setting the priority order will be described with reference to Fig. 10.
In step S80 illustrated in Fig. 10, the controller 50 calculates the time until yarn exhaustion based on the yarn remaining amount and the knitting data. Specifically, the controller 50 calculates the time from the current time until the yarn exhaustion occurs at the yarn cone 141 satisfying the yarn conveyance condition (YES in steps S12, S13, and S14 illustrated in Fig. 4) based on the yarn remaining amount, the knitting data, and the like.
After performing the processing of step S80, the controller 50 proceeds to step S81.
In step S81, the controller 50 sets a priority order in ascending order of time at which the yarn exhaustion occurs. Specifically, the controller 50 sets the priority order of the plurality of yarn cones 141 such that the yarn cone 141 having a shorter time to yarn exhaustion calculated in step S80 is ranked higher.
After performing the processing of step S81, the controller 50 ends priority order setting processing illustrated in Fig. 10.
In this way, in the yarn management system 1, when the yarn cone 141 satisfying the yarn conveyance condition exists in the plurality of flat knitting machines 100, the yarn conveyance is preferentially performed in ascending order of time at which the yarn exhaustion occurs (step S17 illustrated in Fig. 4, step S81 illustrated in Fig. 10, and step S56 illustrated in Fig. 6). Therefore, the flat knitting machine 100 is prevented from stopping due to the yarn exhaustion, and this can eventually prevent a decrease in the production efficiency.
Hereinafter, a third embodiment of the method of setting the priority order will be described with reference to Fig. 11.
In step S90 illustrated in Fig. 11, the controller 50 calculates the time until the yarn exhaustion occurs at the yarn cone 141 satisfying the yarn conveyance condition (YES in steps S12, S13, and S14 illustrated in Fig. 4) based on the yarn remaining amount, the knitting data, and the like.
After performing the processing of step S90, the controller 50 proceeds to step S91.
In step S91, the controller 50 acquires current position information of the yarn conveyor 30 by a GPS function or the like.
After performing the processing of step S91, the controller 50 proceeds to step S92.
In step S92, the controller 50 determines a conveyance route that can maximally prevent yarn exhaustion by a method to be described later. The "conveyance route" indicates how the yarn conveyor 30 travels on a travelling path X when performing the yarn conveyance.
After performing the processing of step S92, the controller 50 proceeds to step S93.
In step S93, the controller 50 sets a priority order based on the conveyance route determined in step S92.
After performing the processing of step S93, the controller 50 ends priority order setting processing illustrated in Fig. 11. An example of the method of determining the conveyance route and the priority order of the yarn conveyor 30 will be described below with reference to Fig. 12.
In the example illustrated in Fig. 12, the flat knitting machine 100A, the flat knitting machine 100B, and the flat knitting machine 100C are arranged along the travelling path X in that order. The yarn conveyor 30 is located near the flat knitting machine 100C. The flat knitting machine 100A has 10 minutes to yarn exhaustion, and the flat knitting machine 100C has 12 minutes to yarn exhaustion. In this case, in accordance with the method of step S81 illustrated in Fig. 10, the yarn is first conveyed to the flat knitting machine A having shorter time until the yarn exhaustion.
However, in this case, since the yarn conveyor 30 is located at a position relatively far from the flat knitting machine 100A, if the yarn is conveyed to the flat knitting machine 100A and then conveyed to the flat knitting machine 100C, a travelling distance of the yarn conveyor 30 and, eventually, travelling time become relatively long. Therefore, in some cases, when the yarn is first conveyed to the flat knitting machine 100A, the yarn may be exhausted in the flat knitting machine 100C during that time.
Thus, in the third embodiment, the conveyance route and the priority order are determined such that the yarn exhaustion can be maximally prevented (such that the flat knitting machine 100 with the yarn exhaustion does not exist) in comprehensive consideration of the position information of the yarn conveyor 30 and the time until the yarn exhaustion of each flat knitting machine 100. For example, by preferentially conveying the yarn to the flat knitting machine 100C having long time until the yarn exhaustion but being close to the position of the yarn conveyor 30, the time required for the yarn conveyance can be reduced, and consequently, the yarn exhaustion of both the flat knitting machine 100A and the flat knitting machine 100C can be prevented.
Hereinafter, a fourth embodiment of the method of setting the priority order will be described with reference to Fig. 13.
In step S100 illustrated in Fig. 13, the controller 50 determines presence or absence of the yarn cone 141 having the yarn remaining amount insufficient for the current product among the yarn cones 141 satisfying the yarn conveyance condition. The specific content is similar to step S32 illustrated in Fig. 5.
Upon determination of presence of a yarn having the yarn remaining amount insufficient for the current product ("YES" in step S100), the controller 50 proceeds to step S101. On the other hand, upon determination of absence of a yarn having the yarn remaining amount insufficient for the current product ("NO" in step S100), the controller 50 proceeds to step S102.
In step S101, the controller 50 calculates the time until the yarn remaining amount becomes "slight". Specifically, the controller 50 calculates the time from the current time until the yarn remaining amount corresponds to "slightly" based on the yarn remaining amount, the knitting data, and the like.
After performing the processing of step S101, the controller 50 proceeds to step S102.
In step S102, the controller 50 determines presence or absence of the yarn cone 141 having the yarn remaining amount insufficient for the next product among the yarn cones 141 satisfying the yarn conveyance condition. The specific content is similar to step S38 illustrated in Fig. 5.
Upon determination of presence of a yarn having the yarn remaining amount insufficient for the next product ("YES" in step S102), the controller 50 proceeds to step S103. On the other hand, upon determination of absence of a yarn having the yarn remaining amount insufficient for the next product ("NO" in step S102), the controller 50 proceeds to step S104.
In step S103, the controller 50 calculates the remaining knitting time. Specifically, the controller 50 calculates the time from the current time to the end of the knitting of the current product based on the knitting data and the like with respect to the flat knitting machine 100 in which the yarn cone 141 having the yarn remaining amount insufficient for the next product is disposed.
After performing the processing of step S103, the controller 50 proceeds to step S104.
In step S104, the controller 50 sets the priority order. Specifically, the controller 50 sets the priority order by the following procedure.
First, the controller 50 sets the priority order such that the yarn cone 141 having the yarn remaining amount insufficient for the current product (YES in step S100) or the yarn cone 141 having the yarn remaining amount insufficient for the next product (YES in step S102) is ranked higher than the yarn cone 141 having the yarn remaining amount not insufficient for the current product and the next product (NO in step S100 and NO in step S102). The yarn cone 141 having the yarn remaining amount not insufficient for the current product and the next product is the yarn cone 141 having the yarn remaining amount satisfying the condition of step S12 illustrated in Fig. 4 not satisfying the conditions of steps S13 and S14.
Next, when the plurality of yarn cones 141 having the yarn remaining amount not insufficient (NO in step S100 and NO in step S102) for the current product and the next product exists, the priority order is set in ascending order of the yarn remaining amount (such that the smaller the yarn remaining amount the higher the yarn cone 141 is ranked) among the plurality of yarn cones 141.
Next, when the plurality of yarn cones 141 having the yarn remaining amount insufficient for the current product or the next product (YES in step S100 or S102) exists, the priority order is set in ascending order of time at which the yarn remaining amount becomes slight (step S101) or in ascending order of the remaining knitting time (step S103) among the plurality of yarn cones 141.
After performing the processing of step S104, the controller 50 ends priority order setting processing illustrated in Fig. 13.
Hereinafter, another specific example of the yarn conveyance and the yarn exchange will be described with reference to Fig. 14. Fig. 14 illustrates a state of the yarn remaining amount and the like of each flat knitting machine 100, and presence or absence of necessity of the yarn exchange and the yarn conveyance of each flat knitting machine 100. In the examples illustrated in Fig. 14, the yarn conveyance and the yarn exchange are performed for three flat knitting machines 100 (flat knitting machine 100A, flat knitting machine 100B, and flat knitting machine 100C). The flat knitting machine 100A uses a knitting yarn YA1 of the yarn cone 141A1, a knitting yarn YA2 of a yarn cone 141A2, and a knitting yarn YA3 of a yarn cone 141A3 for the knitting. The flat knitting machine 100B uses a knitting yarn YB1 of a yarn cone 141B1, a knitting yarn YB2 of a yarn cone 141B2, and a knitting yarn YB3 of a yarn cone 141B3 for the knitting. The flat knitting machine 100C uses a knitting yarn YC1 of a yarn cone 141C1, a knitting yarn YC2 of a yarn cone 141C2, and a knitting yarn YC3 of a yarn cone 141C3 for the knitting.
As illustrated in Fig. 14, in the flat knitting machine 100A, the yarn cone 141A1 satisfies the yarn conveyance condition since the yarn remaining amount corresponds to "slight" (YES in step S12 illustrated in Fig. 4). The yarn cone 141A1 satisfies the yarn conveyance condition, and satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the current product (YES in step S32 illustrated in Fig. 5).
The yarn remaining amount of the yarn cone 141A2 corresponds to "small" (YES in step S12 illustrated in Fig. 4), and thus satisfies the yarn conveyance condition. The yarn cone 141A2 satisfies the yarn conveyance condition, and satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the next product (YES in step S38 illustrated in Fig. 5).
The yarn remaining amount of the yarn cone 141A3 corresponds to "large" (NO in step S12 illustrated in Fig. 4), is sufficient for the current product and the next product (NO in steps S13 and S14 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition. The yarn cone 141A3 does not satisfy the yarn conveyance condition, and thus does not satisfy the yarn exchange condition.
In the flat knitting machine 100B, the yarn remaining amount of the yarn cone 141B1 corresponds to "large" (NO in step S12 illustrated in Fig. 4), is sufficient for the current product and the next product (NO in steps S13 and S14 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition. The yarn cone 141B1 does not satisfy the yarn conveyance condition, and thus does not satisfy the yarn exchange condition.
The yarn remaining amount of the yarn cone 141B2 corresponds to "small" (YES in step S12 illustrated in Fig. 4), and thus satisfies the yarn conveyance condition. The yarn cone 141B2 satisfies the yarn conveyance condition, and satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the next product (YES in step S38 illustrated in Fig. 5).
The yarn remaining amount of the yarn cone 141B3 corresponds to "large" (NO in step S12 illustrated in Fig. 4), is sufficient for the current product and the next product (NO in steps S13 and S14 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition. The yarn cone 141B3 does not satisfy the yarn conveyance condition, and thus does not satisfy the yarn exchange condition.
In the flat knitting machine 100C, the yarn remaining amount of the yarn cone 141C1 corresponds to "small" (YES in step S12 illustrated in Fig. 4), and thus satisfies the yarn conveyance condition. The yarn cone 141C1 satisfies the yarn conveyance condition, and also satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the next product (YES in step S38 illustrated in Fig. 5).
The yarn remaining amount of the yarn cone 141C2 corresponds to "large" (NO in step S12 illustrated in Fig. 4), is sufficient for the current product and the next product (NO in steps S13 and S14 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition. The yarn cone 141C2 does not satisfy the yarn conveyance condition, and thus does not satisfy the yarn exchange condition.
The yarn remaining amount of the yarn cone 141C3 corresponds to "slightly" (YES in step S12 illustrated in Fig. 4), and thus does not satisfy the yarn conveyance condition, but it is assumed here that the yarn conveyance has been already performed. The yarn cone 141C3 satisfies the yarn conveyance condition, and also satisfies the yarn exchange condition since the yarn remaining amount is insufficient for the next product (YES in step S38 illustrated in Fig. 5).
In this way, the yarn cone 141 satisfying the yarn conveyance condition exists in the plurality of flat knitting machines 100 (YES in step S16 illustrated in Fig. 4). Specifically, the yarn cones 141A1 and 141A2 of the flat knitting machine 100A, the yarn cones 141B2 of the flat knitting machine 100B, and the yarn cones 141C1 of the flat knitting machine 100C satisfy the yarn conveyance condition, and the yarn conveyance preparation instruction has not been issued (NO in step S15 and YES in step S16 illustrated in Fig. 4), and therefore the priority order setting processing (step S17 illustrated in Fig. 4) is performed.
As described above, the yarn remaining amounts of all the yarn cones 141 satisfying the yarn conveyance condition are insufficient for the current product or the next product. That is, among the yarn cones 141 satisfying the yarn conveyance condition, no yarn cone is not insufficient for the current product or the next product.
Of the yarn cones 141 (yarn cone 141A1, yarn cone 141A2, yarn cone 141B2, and yarn cone 141C1) satisfying the yarn conveyance condition, the yarn remaining amount of the yarn cone 141A1 is insufficient for the current product. The yarn remaining amount of the yarn cone 141A1 already corresponds to "slightly", and thus the time until the yarn remaining amount becomes "slightly" is 0 minute.
Further, the yarn remaining amounts of the yarn cones 141A2, the yarn cones 141B2, and the yarn cones 141C1 are insufficient for the next product. The remaining knitting time of the flat knitting machine 100A in which the yarn cone 141A2 is disposed is 40 minutes. The remaining knitting time of the flat knitting machine 100B in which the yarn cone 141B2 is disposed is 25 minutes. The remaining knitting time of the flat knitting machine 100C in which the yarn cone 141C1 is disposed is 10 minutes.
Therefore, the time until the yarn remaining amount becomes slight or the time until the end of the knitting is earlier in the order of the yarn cone 141A1, the yarn cone 141C1, the yarn cone 141B2, and the yarn cone 141A2. Therefore, the priority order is set such that the yarn cone 141A1 is ranked first, the yarn cone 141C1 is ranked second, the yarn cone 141B2 is ranked third, and the yarn cone 141A2 is ranked fourth (step S70 illustrated in Fig. 8).
The yarn conveyor 30 first performs the yarn conveyance preparation of the yarn cone 141A1, the yarn cone 141C1, the yarn cone 141B2, and the yarn cone 141A2 (step S51 illustrated in Fig. 6). Upon completion of all the yarn conveyance preparation (YES in step S53 illustrated in Fig. 6), the yarn conveyor 30 issues the yarn conveyance preparation completion report to the controller 50 (step S54 illustrated in Fig. 6).
Upon receipt of the yarn conveyance preparation completion report, the controller 50 issues the yarn conveyance execution instruction to the yarn conveyor 30 (step S20 illustrated in Fig. 4). Upon receipt of the yarn conveyance execution instruction (YES in step S55 illustrated in Fig. 6), the yarn conveyor 30 first conveys the yarn cone 141A1 ranked first in the priority order to the flat knitting machine 100A, and can also convey the yarn cone 141A2 used in the same flat knitting machine 100A. That is, the yarn conveyor 30 performs the yarn conveyance of the yarn cones 141A1 and 141A2 with respect to the flat knitting machine 100A. Upon completion of the yarn conveyance to the flat knitting machine 100A, the yarn conveyor 30 conveys the yarn cone 141C1 ranked second in the second priority order to the flat knitting machine 100C. Upon completion of the yarn conveyance to the flat knitting machine 100C, the yarn conveyor 30 conveys the yarn cone 141B2 ranked third in the priority order to the flat knitting machine 100B.
In this way, the new yarn cone 141 is conveyed to the flat knitting machine 100A, the flat knitting machine 100B, the flat knitting machine 100C, the yarn conveyance is completed (YES in step S59 illustrated in Fig. 6 and step S21 illustrated in Fig. 4), and the yarn conveyance instruction control by the controller 50 (Fig. 4) and the yarn conveyance processing by the yarn conveyor 30 (Fig. 6) end.
Upon receipt of the yarn conveyance completion report (YES in step S30 illustrated in Fig. 5), the controller 50 issues the yarn exchange preparation instruction to the yarn exchanger 40 corresponding to the yarn cone 141 satisfying the yarn exchange condition. Specifically, since the yarn remaining amount of the yarn cone 141A1 is insufficient for the current product (YES in step S32 illustrated in Fig. 5), the controller 50 issues the yarn exchange preparation instruction to the yarn exchanger 40A of the flat knitting machine 100A (step S33 illustrated in Fig. 5). The yarn remaining amounts of the yarn cone 141C1, the yarn cone 141B2, and the yarn cone 141A2 are insufficient for the next product (YES in step S38 illustrated in Fig. 5), and thus the controller 50 waits for the remaining knitting time to become less than 10 minutes and issues the yarn exchange preparation instruction to each yarn exchanger 40 (steps S39 and S40 illustrated in Fig. 5).
First, the yarn exchange of the flat knitting machine 100A will be described below.
Upon completion of the yarn exchange preparation of the yarn cone 141A1, the controller 50 receives the yarn exchange preparation completion report from the yarn exchanger 40A (YES in step S34 illustrated in Fig. 5). Since the knitting status of the yarn cone 141A1 (yarn carrier 131 of the knitting yarn YA1) is stopped (NO in step S36 illustrated in Fig. 5), and the yarn carrier 131 is to be operated after 10 minutes (YES in step S37 illustrated in Fig. 5), the controller 50 immediately issues the yarn exchange execution instruction to the yarn exchanger 40A of the flat knitting machine 100A (step S45 illustrated in Fig. 5). Upon completion of the yarn exchange preparation of the yarn cone 141A2, the controller 50 receives the yarn exchange preparation completion report from the yarn exchanger 40A (YES in step S34 illustrated in Fig. 5). The knitting of the flat knitting machine 100A in which the yarn cone 141A2 is disposed ends after 40 minutes. In a case where the knitting until the next carrier stop will be completed with the yarn remaining amount at the time of completing the knitting of the current product (YES in step S43 illustrated in Fig. 5), the controller 50 issues the yarn exchange execution instruction of the yarn cone 141A2 to the yarn exchanger 40A at the time of carrier stop immediately before the yarn exhaustion after the start of knitting of the next product (steps S44 and S45 illustrated in Fig. 5).
In this way, the yarn exchanger 40A having received the yarn exchange execution instruction immediately performs the yarn exchange of the yarn cone 141A1, and further performs the yarn exchange of the yarn cone 141A2 after the start of the knitting of the next product.
Next, the yarn exchange of the flat knitting machine 100C will be described.
Upon completion of the yarn exchange preparation of the yarn cone 141C1, the controller 50 receives the yarn exchange preparation completion report from the yarn exchanger 40C (YES in step S41 illustrated in Fig. 5). The knitting of the flat knitting machine 100C in which the yarn cone 141C1 is disposed ends after 10 minutes. In a case where the knitting until the next carrier stop will be completed with the yarn remaining amount at the time of completing the knitting of the current product (YES in step S43 illustrated in Fig. 5), the controller 50 issues the yarn exchange execution instruction of the yarn cone 141C1 to the yarn exchanger 40C at the time of carrier stop immediately before the yarn exhaustion after the start of knitting of the next product (steps S44 and S45 illustrated in Fig. 5).
In this way, the yarn exchanger 40C having received the yarn exchange execution instruction performs the yarn exchange of the yarn cone 141C1 after the start of the knitting of the next product.
Next, the yarn exchange of the flat knitting machine 100B will be described.
Upon completion of the yarn exchange preparation of the yarn cone 141B2, the controller 50 receives the yarn exchange preparation completion report from the yarn exchanger 40B (YES in step S41 illustrated in Fig. 5). The knitting of the flat knitting machine 100B in which the yarn cone 141B2 is disposed ends after 25 minutes. In a case where the knitting cannot be completed until the next carrier stop with the yarn remaining amount at the end of the knitting of the current product (NO in step S43 illustrated in Fig. 5), the controller 50 issues the yarn exchange execution instruction of the yarn cone 141B2 to the yarn exchanger 40B immediately after the end of the knitting of the current product (after 25 minutes) (steps S44 and S45 illustrated in Fig. 5).
In this way, the yarn exchanger 40B having received the yarn exchange execution instruction performs the yarn exchange of the yarn cone 141B2 immediately after the end of the knitting of the current product (after 25 minutes).
As described above, in the yarn management system 1, the yarn conveyance and the yarn exchange of each yarn cone 141 of each flat knitting machine 100 can be optimally performed, and consequently, the occurrence of yarn exhaustion can be suppressed.
Note that the control flow illustrated in the specification and the drawings is merely an example, and can be appropriately changed within the scope of the technical idea of the disclosure.

Claims

A yarn management system (1) comprising:
a yarn remaining amount detector (10) configured to detect a yarn remaining amount as a remaining amount of a yarn (141, Y) disposed in a knitting machine (100);

a storage (20) configured to store knitting data of a knitted fabric (K);

a controller (50) configured to manage the yarn (141, Y) to be fed to the knitting machine (100); and

at least one of a yarn conveyor (30) configured to convey the yarn (141, Y) to the knitting machine (100) or a yarn exchanger (40) configured to exchange the yarn (141, Y) disposed in the knitting machine (100) with a new yarn (141, Y), wherein

upon determination of presence of the yarn (141, Y) satisfying a management condition calculated based on the yarn remaining amount and the knitting data, the controller (50) manages the yarn (141, Y) by the at least one of the yarn conveyor (30) or the yarn exchanger (40).
The yarn management system (1) as claimed in claim 1, wherein when the yarn (141, Y) having the yarn remaining amount less than or equal to a predetermined threshold value exists, the controller (50) determines that the yarn (141, Y) satisfies the management condition.
The yarn management system (1) as claimed in claim 1 or 2, wherein upon determination of presence of the yarn (141, Y) not allowing knitting of the knitted fabric (K) being knitted or the knitted fabric (K) to be knitted next with the yarn remaining amount at a current point of time, the controller (50) determines that the yarn (141, Y) satisfies the management condition.
The yarn management system (1) as claimed in any one of claims 1 to 3, further comprising a yarn conveyor (30) configured to convey the yarn (141, Y) to the knitting machine (100), wherein
the management condition includes a yarn conveyance condition, and

upon determination of presence of the yarn (141, Y) satisfying the yarn conveyance condition in a plurality of the knitting machines (100), the controller (50) preferentially conveys the yarn by the yarn conveyor (30) in ascending order of the yarn remaining amount or in ascending order of time at which the yarn is exhausted.
The yarn management system (1) as claimed in any one of claims 1 to 4, further comprising the yarn conveyor (30) configured to convey the yarn (141, Y) to the knitting machine (100), wherein
the management condition includes the yarn conveyance condition, and

upon determination of presence of the yarn (141, Y) satisfying the yarn conveyance condition in the plurality of knitting machines (100), the controller (50) acquires position information of the yarn conveyor (30) and determines a conveyance order of the yarn (141, Y) based on the position information of the yarn conveyor (30) that has been acquired.
The yarn management system (1) as claimed in any one of claims 1 to 5, further comprising a yarn exchanger (40) configured to exchange the yarn (141, Y) disposed in the knitting machine (100) with the new yarn (141, Y), wherein
the management condition includes a yarn exchange condition, and

the controller (50) exchanges the yarn (141, Y) satisfying the yarn exchange condition by the yarn exchanger (40) during a period when the yarn (141, Y) is not used for knitting based on the knitting data.
The yarn management system (1) as claimed in any one of claims 1 to 6, further comprising the yarn exchanger (40) configured to exchange the yarn (141, Y) disposed in the knitting machine (100) with the new yarn (141, Y), wherein
the management condition includes the yarn exchange condition, and

upon determination that the yarn (141, Y) not allowing knitting of the knitted fabric (K) to be knitted next with the yarn remaining amount at the current point of time exists and thus the yarn (141, Y) satisfies the yarn exchange condition, the controller (50) calculates how far the knitted fabric (K) to be knitted next is to be knitted based on the yarn remaining amount and the knitting data, and then the controller (50) determines time to exchange the yarn (141, Y) in accordance with a calculation result.