CH710192A2 - A device and method for monitoring of a yarn winding machine and a yarn. - Google Patents

Abstract

A control section of the yarn clearer of an optical yarn clearer comprises an adjustment section and a process section for responding to foreign substances. The adjustment section performs an adjustment process to adjust an actuation control value of a light projection section. The foreign substance response process section performs a foreign substance response process when a detection value corresponding to a light receiving amount of a light receiving section is outside a predetermined range of foreign matter determination continuously for a predetermined time in a state in which the yarn is not present in the detection region. The adjustment section performs the adjustment process again when the detection value is outside a normal range in a state in which the yarn is not present in the detection region.

Description

INTRODUCTION TO THE INVENTION

1. Field of invention

[0001] The present invention mainly relates to a yarn monitoring device suitable for monitoring a moving yarn and a method for monitoring it.

2. Description of the known art

[0002] Conventionally, a yarn winding machine configured to wind a yarn around a bobbin, such as a spinning machine and an automatic winder, is known. This type of yarn winding machine comprises a yarn monitoring device (yarn clearer). An optical monitoring device of a yarn irradiates the moving yarn with light and measures the light transmitted through the yarn or light reflected from the yarn in order to monitor the state of the yarn in real time and detect a yarn defect (portion with a anomaly in yarn quality).

[0003] The Japanese unexamined patent publication n. 2013-204 190 and the Japanese patent n. 3 707 413 disclose a yarn winding machine equipped with a monitoring device for a yarn of this type.

[0004] The monitoring device of a yarn (yarn clearer) of the unexamined Japanese patent publication n. 2013-204 190 includes a yarn clearer head with a LED and a yarn irregularity sensor. The yarn clearer is configured to perform a contamination determination process to determine the presence / absence of an anomaly such as contamination of the yarn clearer head. In the clearer of the unexamined Japanese patent publication n. 2013-204 190, before the contamination determination process a regulation process of an actuation voltage is applied which is applied to the LED, so that the voltage corresponding to the detection signal when nothing is present in the yarn path of the device yarn monitoring becomes a predefined tension. With this configuration of the unexamined Japanese patent publication n. 2013-204 190, it is possible to accurately detect an anomaly such as contamination of the clearer head.

[0005] The monitoring device of a yarn (detector of the thickness of a yarn) of the Japanese patent n. 3 707 413 performs a process of adjusting a substrate circuit constant so that the output signal is reset to a state in which the yarn is not present in the detection region with a timing dictated by the unit controller in the operation of rising. According to this configuration, the Japanese patent n. 3 707 413 can effectively avoid the occurrence of the zero point shift.

[0006] The yarn monitoring device of the Japanese patent n. 5 283 003 relates to a yarn clearer of the capacitive type rather than of the optical type. The Japanese patent n. 5 283 003 discloses the distinction between the factor by which the modifications of the clearer signal are due to particles of solid foreign substances contained in the yarn and the factor by which the changes in the signal of yarn clearer are due to the local humidity fluctuation.

[0007] In the winding machine of a yarn, the yarn to be wound runs at high speed and, therefore, it is probable that foreign substances such as fiber waste are formed at its perimeter. Since the fiber waste is light, it floats around the yarn winding machine and can enter the sensing region of the yarn monitoring device.

[0008] As described above, in the monitoring device of a yarn disclosed in the unexamined Japanese patent publication n. 2013-204 190 and in the Japanese patent n. 3 707 413, the process of adjusting the drive voltage which is applied to the LED and the process of adjusting the substrate circuit constant to reset the output signal are performed in a state in which the yarn is not present in the detection region of the yarn monitoring device, so that the yarn can be accurately monitored. However, if the foreign substances enter the detection region or leave the detection region, generally the accuracy of the yarn monitoring is greatly reduced. Specifically, even if the processes described above are carried out in a state in which the foreign substances are not present in the detection region, when subsequently the foreign substances enter the detection region the state of the yarn cannot be accurately assessed. The same can occur in the following case. If the processes described above are carried out in a state in which the foreign substances enter the detection region and subsequently leave the detection region, the state of the yarn subsequently cannot be accurately assessed.

[0009] In this regard, the Japanese patent n. 5 283 003 describes the specification of the factor by which the clearer signal changes, but does not disclose the influence of the foreign substances entering the detection region or leaving the detection region.

BRIEF SUMMARY OF THE INVENTION

[0010] The present invention has been realized in the light of the above circumstances and one of its main object consists in providing a monitoring device for a yarn capable of accurately monitoring the yarn even when foreign substances enter the detection region or they leave the detection region, and a corresponding monitoring method.

[0011] The problems which the present invention intends to solve are described above; the means and effects to solve these problems will be described below.

[0012] According to a first aspect of the present invention, a monitoring device is provided for a yarn having the following configuration. Specifically, a yarn monitoring device comprises a light projection section, a light receiving section and a control section. The light projection section is adapted to project light onto a sensing region through which a yarn can slide. The light receiving section is adapted to receive the light projected by the light projection section. The control section receives a detection value corresponding to an amount of light reception from the light receiving section. The control section includes an evaluation section, a light projection adjustment section and a foreign substance response process section. The evaluation section is suitable for evaluating a state of the yarn present in the detection region based on the detection value. The light projection adjustment section is adapted to perform a light projection adjustment process to adjust an actuation control value of the light projection section such that the detection value becomes a predetermined value in a state in where the yarn is not present in the detection region. The foreign substance response process section is adapted to perform a process of response to foreign substances when the detection value is outside a predetermined range of determination of the foreign substances for a predetermined time to determine the foreign substances. in the state in which the yarn is not present in the detection region. The light projection adjustment section performs the light projection adjustment process again when the detection value is outside a normal range, which is an interval of a preset detection value so as to have a greater width with respect to the width of the determination range of the foreign substances when the yarn is not present in the detection region.

[0013] Therefore, if the detection value in the state in which the yarn is not present in the detection region is outside the range of determination of foreign substances in a continuous manner for a predetermined time of determination of foreign substances, it is determined that the state of entry of the foreign substances has changed and the predetermined process of response to foreign substances is performed and, therefore, it is possible to respond appropriately to the entry / exit of foreign substances. In the condition in which, for example, the detection value is outside the range of determination of foreign substances in a continuous manner for a predetermined time of determination of foreign substances, it is possible to prevent the entry status of the foreign substances from being erroneously determined as changed even if the detection value entered into the control section becomes unstable during the normal doffing operation of a yarn equipped with a yarn monitoring device in the winding machine.

[0014] In the yarn monitoring device described above, the light projection adjustment section preferably again performs the light projection adjustment process when the detection value is continuously outside the normal range for a time for determining the projection of the predetermined light in the state in which the yarn is not present in the detection region.

[0015] In this case, for example, it is possible to prevent the wasteful process of adjusting the projection of light from being performed due to the noise present in the detection value.

[0016] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the monitoring device of a yarn comprises a device for removing foreign substances suitable for eliminating foreign substances present in the detection region. The foreign substance response process performed by the foreign substance response process section includes a process of actuating the foreign substance elimination device.

[0017] Therefore, it is possible to eliminate the foreign substances of the detection region and obtain a state suitable for the process of adjusting the light projection and the like.

[0018] In the monitoring device of a yarn described above, the device for eliminating foreign substances preferably eliminates the foreign substances by blowing air into the detection region.

[0019] Therefore, it is possible to eliminate the foreign substances present in the detection region with a simple configuration.

[0020] In the yarn monitoring device described above, the foreign substance response process performed by the foreign substance response process section preferably comprises the step of inducing the light projection adjustment section to re-execute the process of light projection adjustment.

[0021] When the light projection adjustment process is performed again, the influence of the foreign substances with respect to the detection value can be effectively eliminated.

[0022] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the monitoring device of a yarn further comprises a section for determining the presence / absence of a yarn suitable for determining whether the yarn is present or is not present in the detection region. The foreign substance response process performed by the foreign substance response process section includes an operating process as if the yarn were not present in the detection region even when the yarn presence / absence determination section determines that the yarn is present in the detection region.

[0023] This means that, as the foreign substance response process section determines that the foreign substances have entered or exited, the yarn monitoring device cannot accurately assess the yarn due to the influence of foreign substances. and, therefore, it is not appropriate to start the winding in the winding machine of a yarn comprising this yarn monitoring device. Therefore, in this case, the yarn monitoring device works (behaves) as if the yarn were not set, so that, subsequently, it is possible to reliably prevent the start of the winding.

[0024] In the monitoring device of a yarn described above, the section for determining the presence / absence of the yarn preferably determines whether the yarn is positioned in the yarn path in the detection region.

[0025] Therefore, the yarn monitoring device can reliably detect whether or not the yarn is present in the yarn path. Moreover, when the process section of response to foreign substances determines that the foreign substances have entered or exited, the monitoring device of a yarn can function as if the yarn were not present in the yarn path.

[0026] In the monitoring device of a yarn described above, the process of response to foreign substances carried out by the foreign substance response process section preferably comprises a process for the emission of a foreign substance detection signal.

[0027] Preferably, the yarn monitoring device described above has the following configuration. Specifically, a textile machine comprising the yarn monitoring device comprises a winding section suitable for winding the yarn and forming a cone. The foreign substance response process performed by the foreign substance response process section includes a process of emitting a winding inhibit signal to prevent the winding of the yarn by the winding section.

[0028] Preferably, the yarn monitoring device described above has the following configuration. Specifically, a textile machine comprising the yarn monitoring device comprises a splicing device for a yarn suitable for performing a yarn splicing operation. The process of response to foreign substances carried out by the foreign substance response process section comprises a process of emission of a yarn junction signal to induce the yarn splicing device to perform the yarn splicing operation.

[0029] Therefore, it is possible to perform various processes of response to foreign substances.

[0030] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the yarn monitoring device includes a notification device. The notification device is able to create a notification when the detection value is outside the range of determination of foreign substances continuously for the time of determination of foreign substances in the state in which the yarn is not present in the region of detection.

[0031] Therefore, the operator can understand the entry and exit of the foreign substances in and from the detection region thanks to the notification of the notification device. Furthermore, for example, the operator can manually stop the winding of the yarn winding machine comprising the yarn monitoring device by notification.

[0032] In the yarn monitoring device described above, the notification device is preferably a display device capable of displaying at least one of characters, symbols and digits.

[0033] Therefore, it is possible to create a notification for the operator in a very simple manner. The detailed content can be notified to the operator by displaying characters and similar on the screen.

[0034] In the monitoring device of a yarn, the notification device is preferably a lighting device which can be switched on.

[0035] Therefore, it is possible to create a notification for the operator in a very simple manner. Furthermore, a state relating to foreign substances can be notified by the lighting state of the lighting device, so that the operator can easily check the entry / exit of foreign substances even from a remote location.

[0036] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the foreign substance response process section determines that the foreign substances entered the detection region when a state in which the detection value is outside the range of determination of foreign substances beyond a limit value in a side of the determination range of the foreign substances continues for a predetermined time in the state in which the yarn is not present in the sensing region. The process section of response to foreign substances determines that the foreign substances have left the detection region when a state in which the detection value is outside the range of determination of foreign substances beyond a limit value on the other side of the the determination range of the foreign substances continues for a predetermined time in the state in which the yarn is not present in the detection region.

[0037] Therefore, the process section of response to foreign substances can determine, in a distinct manner, the entry and exit of foreign substances in and from the detection region.

[0038] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the determination range of foreign substances is defined relatively with a reference value, which is a past detection value, as a reference. When the reference value is greater than or equal to a lower limit value and less than or equal to an upper limit value of the determination range of foreign substances, the foreign substance response process section uses a new range of determination of foreign substances defined with the relevant detection value as a reference value in the subsequent determination.

[0039] Therefore, the foreign substance response process section may know very accurately if the input state of foreign substances in the detection region has changed.

[0040] However, in the monitoring device of a yarn, the range of determination of foreign substances can be defined in a fixed manner.

[0041] In this case, it is possible to easily determine the entry / exit of foreign substances.

[0042] Preferably, the yarn monitoring device described above has the following configuration. Specifically, the monitoring device of a yarn further comprises a section for determining the presence / absence of a yarn suitable for determining whether the yarn is present or is not present in the detection region. The determination of the presence / absence of the yarn determines that the yarn is present in the detection region when the detection value is greater than or equal to the threshold value for determining the presence / absence of the yarn. The threshold value for determining the presence / absence of the yarn is set outside the range of determination of foreign substances.

[0043] Therefore, the monitoring device of a yarn can know of the presence of the yarn in a manner distinct from foreign substances such as fiber waste.

[0044] According to a second aspect of the present invention, a yarn winding machine is provided comprising the yarn monitoring device, and a winding section adapted to wind a yarn passing through the yarn monitoring device for to form a fortress.

[0045] Therefore, it is possible to accurately assess the state of the yarn and wrap the yarn while simultaneously carrying out the process of responding to the entry / exit of foreign substances into and from the detection region. According to a third aspect of the present invention, a method for monitoring a yarn is provided.

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] <tb> Fig. 1 <SEP> is a side view schematically illustrating a unit for winding a yarn according to an embodiment of the present invention; fig. 2 <SEP> is a side view of a yarn winding unit illustrating a state in which the ends of the yarn are captured by a first yarn capture device and a second yarn capture device; fig. 3 <SEP> is a side view of the winding unit of a yarn illustrating a state in which the ends of the yarn are guided towards a yarn joining device by means of the first yarn capture device and the second yarn capture device ; fig. 4 <SEP> is a perspective view showing a configuration of a yarn clearer; fig. 5 <SEP> is a block diagram illustrating an electrical configuration of the yarn clearer fig. 6 <SEP> is a graph illustrating an example of a transition of the detection value until the yarn is introduced into the detection region; fig. 7 <SEP> is a graph showing an example of a transition of the detection value when the foreign substances enter before the yarn is introduced into the detection region; fig. 8 <SEP> is a graph illustrating an example of a transition of the detection value when foreign substances enter before the introduction of the yarn into the detection region but the foreign substances immediately exit; fig. 9 <SEP> is a graph illustrating a process of a case in which the detection value is significantly increased due to the influence of the thermal drift; fig. 10 <SEP> is a graph illustrating an example of a transition of the detection value when the foreign substances enter the detection region but the foreign substances exit before the introduction of the yarn; fig. 11 <SEP> is a flow chart illustrating a process performed by a clearer control section; is fig. 12 <SEP> is a graph illustrating an alternative embodiment in which a range of determination of the foreign substances is defined in a fixed manner.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0047] In the following, embodiments of the present invention will be described with reference to the drawings. Fig. 1 is a schematic side view of a unit for winding a yarn 1 arranged in a machine for winding a yarn according to an embodiment of the present invention.

[0048] The yarn winding machine of the present embodiment has a configuration in which a plurality of yarn winding units 1 are arranged in a row. The yarn winding machine comprises a machine management device (not shown) which intensively manages the yarn winding unit 1.

[0049] The winding unit of a yarn 1 shown in fig. 1 is configured to wind a yarn 10 fed by a yarn feeding section (not shown) around a winding bobbin to form a bobbin 20. The configuration drawn in the figure illustrates a common portion to describe two cases: when the unit winding of a yarn 1 is a spinning unit of a spinning machine and when the winding unit of a yarn 1 is a winding unit of an automatic winder. When the winding unit of a yarn 1 is the spinning unit of the spinning machine, for example, the pneumatic spinning device corresponds to the yarn feeding section. When the winding unit of a yarn 1 is the winding unit of the automatic winder, a mechanism able to support the yarn supplying bobbin corresponds to the yarn feeding section.

[0050] Each yarn winding unit 1 comprises a control section of the unit 30 configured by means of a computer. The control section of the unit 30 is configured by hardware, such as CPU, ROM and RAM, and software, such as a control program stored in ROM and / or RAM. Through the cooperation of hardware and software, the control section of the unit 30 controls each component of the yarn winding unit 1. The control section of the unit 30 of each yarn winding unit 1 is configured to be able to communicate with the machine management device. Therefore, the operation of each yarn winding unit 1 can be intensively managed by the machine management device.

[0051] The yarn winding unit 1 comprises, from the upstream position in the direction of movement of the yarn 10, an upstream guide 11, a yarn clearer (yarn monitoring device) 15, a downstream guide 17 and a winding section 18. When the yarn winding unit, the spinning unit, a first yarn capture device 12, a second yarn capture device 13 and a yarn joining device 14 can be arranged for each unit, but one or a plurality of yarn junction trolleys can be arranged in common for a plurality of units, and the first yarn capture device 12, the second yarn capture device 13 and the yarn splicing device 14 are preferably arranged on the yarn splicing carriage. When the yarn winding unit 1 is the winding unit, the first yarn capture device 12, the second yarn capture device 13 and the yarn junction device 14 are preferably provided for each unit. The junction device of the yarn 14 is positioned upstream of the yarn clearer 15.

[0052] The upstream guide 11 is arranged downstream of the yarn feeding section. The upstream guide 11 guides the yarn 10 fed by the yarn feeding section.

[0053] The first yarn capture device 12 is configured to oscillate, as shown in figs. from 1 to 3, when the control section of the unit 30 drives a motor (not shown). The first yarn capture device 12 is connected to a negative pressure source (not shown) and can generate a suction flow in a distal end side (opposite to the center of oscillation) of the first yarn capture device 12. The first yarn capture device 12 is arranged so that the center of oscillation is upstream of the yarn joining device 14.

[0054] The second yarn capture device 13 is configured to oscillate, similarly to the first yarn capture device 12, when the control section of the unit 30 drives a motor (not shown). The second yarn capture device 13 is connected to a negative pressure source (not shown) and can generate a suction flow in a distal end side (opposite to the oscillation center) of the second yarn capture device 13. The second yarn capture device 13 is arranged so that the center of oscillation is upstream of the yarn joining device 14.

[0055] The yarn clearer (yarn monitoring device) 15 monitors the state (thickness, mixture of foreign substances such as colored yarn, polypropylene and the like) of the moving yarn 10 and detects a yarn defect (portion with an anomaly in the yarn 10) contained in the yarn 10. The yarn clearer 15 also comprises a cutter (cutting device) 16 able to cut the yarn 10 when the yarn clearer 15 detects the yarn defect. The detailed configuration of the yarn clearer 15 will be described below.

[0056] The downstream guide 17 is arranged slightly downstream of the yarn clearer 15. The downstream guide 17 guides the yarn 10 fed towards the winding section 18.

[0057] The winding section 18 comprises a support section of a bobbin (not shown) and a winding cylinder 19. The winding cylinder 19 is operated at the same time creating a contact with the outer perimetric surface of the winding bobbin 21 or of the bobbin 20. The winding section 18 drives the winding cylinder 19 by means of a motor (not shown) and winds the yarn 10 while translating at the same time the yarn 10 while rotating the bobbin 20, which creates a contact with the winding cylinder 19, to form the fortress 20.

[0058] The method for carrying out the translation is arbitrary, and the translation device can be arranged individually for each yarn winding unit 1 or a translation device can translate the yarn 10 of a plurality of yarn winding units 1. The translation device arranged singularly for each winding unit of a yarn 1 can be a translation groove formed in the winding cylinder 19 or an arm translation device. Preferably, the arm translation device is applied to a direct drive structure of the winding bobbin 21 by means of a motor (not shown).

[0059] The yarn winding unit 1 is configured as described above, so that the yarn 10 fed by the yarn supply section can be wound while being moved with the winding section 18 to form the bobbin 20.

[0060] If the yarn 10 between the yarn supply section and the winding section 18 is interrupted for some reason, the first yarn capture device 12, the second yarn capture device 13, the yarn splicing device 14 and the like cooperate to carry out a series of steps in the yarn splicing operation to return the yarn 10 to the combined state.

[0061] These steps will be described below. When the yarn 10 is interrupted, at first the winding section 18 immediately stops the winding if the winding section 18 is winding. Subsequently, as shown in fig. 2, the first yarn capture device 12 is made to oscillate towards the yarn supply section to aspirate and capture the end of the yarn from the yarn supply section. Substantially at the same time, the second device for capturing the yarn 13 is made to oscillate towards the winding section 18 to aspirate and capture the end of the yarn from the winding section 18.

[0062] Subsequently, the first yarn capture device 12 and the second yarn capture device 13 are oscillated respectively to return to the waiting positions while aspirating the ends of the yarn. Therefore, as shown in fig. 3, the end of the yarn from the yarn supply section and the end of the yarn from the winding section 18 are fed to the yarn joining device 14. Furthermore, the yarn 10 is set in the yarn clearer 15 substantially with the same timing with which the ends of the yarn are guided, and the yarn 10 is detected by the yarn clearer 15.

[0063] The yarn joining device 14 is configured as a pneumatic splicer which exerts a vortex flow of air on the end of the yarn from the yarn supply section and on the end of the yarn from the winding section 18 to twist and connect the two ends of the yarn. The junction device of the yarn 14 is not limited to this and can be, for example, a mechanical knotter.

[0064] According to the steps described above, the yarn 10 in the interrupted state can be joined in the junction device of the yarn 14 to return to the combined state. The series of steps of the yarn splicing operation are repeated each time the yarn 10 is interrupted. Therefore, sometimes the series of steps described above are called "yarn splicing cycle".

[0065] The yarn splicing cycle is performed in such a way that the control section of the unit 30 controls the first yarn capture device 12, the second yarn capture device 13, the yarn splicing device 14 and similar so that they work with appropriate timing.

[0066] The operation of setting the yarn 10 in the yarn clearer 15 is performed with the timing with which the end of the yarn is guided in the junction device of the yarn 14 (that is, immediately before the yarn splicing operation by means of 11 the junction device of the yarn 14), the timing preceding the resumption of winding after the doffing and the like. The control section of the unit 30 determines whether the yarn 10 is normally set in the yarn clearer 15 in the yarn splicing cycle based on the fact that an appropriate signal (specifically, the yarn presence signal, which will be described below) coming from from the yarn clearer 15 is sent or not to the control section of the unit 30. If the signal of presence of the yarn coming from the yarn clearer 15 is not sent to the control section of the unit 30, which means that the yarn 10 cannot be monitored by the yarn clearer 15, the control section of the unit 30 assumes that the yarn splicing cycle has failed, cancels the yarn splicing operation by means of the yarn junction device 14 and performs the series of steps again from the beginning.

[0067] When the yarn 10 of a predetermined length is wound around the winding bobbin 21 and the bobbin 20 is completely wound, the yarn 10 is automatically cut by the cutter 16 of the yarn clearer 15 and the winding of the winding section 18 is arrested. Subsequently, the cone 20 is detached from the winding section 18 by a manual operation of an operator and an empty winding reel 21 is attached to the winding section 18 in place of the cone 20 and the winding starts again. The doffing operation may not be a manual operation and can be performed using a known automatic doffing device.

[0068] Next, a configuration of the yarn clearer 15 will be described with reference to fig. 4 Fig. 4 is a perspective view showing a configuration of the yarn clearer 15.

[0069] As shown in fig. 4, the yarn clearer 15 of the present embodiment comprises an optical sensor unit (sensing section) 35 capable of measuring the state of the yarn 10. The sensor unit 35 comprises a housing 37.

[0070] The housing 37 is formed with a slot-shaped recess 38 and the yarn 10 can slide inside the recess 38. The recess 38 is formed as a linear groove with an open side, and the sensing region 36 is located inside the recess 38. The detection region 36 is a region in which the light is projected from the projection section of the light 41 and is a region in which the yarn 10 can be detected according to the light receiving quantity of the light receiving section 42 which will be described below.

[0071] The yarn clearer 15 comprises the cutter 16, as described below, and is arranged so that the cutting blade of the cutter 16 emerges (advances / retracts) on the upstream side in the direction of movement of the yarn of the region d detection 36 in the withdrawal 38.

[0072] The yarn path guides 131, 132 designed to guide the yarn 10 flowing through the recess 38 are attached to the housing 37. A light indicator (notification device, lighting device) 46 is installed on the housing 37 in such a way that the status of the yarn clearer 15 can be indicated and an anomaly can be notified to the operator through the lit status of the light indicator 46.

[0073] Furthermore, a display device (notification device, display) 47 is installed on the housing 37. The display device 47 is configured as a liquid crystal display device, for example, and can display characters, symbols, figures and the like, if necessary. Therefore, the display device 47 can notify the operator of the information relating to the operating status of the yarn clearer 15 in a more specific manner with respect to the light indicator 46. For example, when an anomaly occurs in the yarn clearer 15, this anomaly can be notified to the operator by displaying a warning screen.

[0074] Two blowing lights, i.e. a first blowing port 151 and a second blowing port 152 which can expel compressed air are formed in the housing 37.

[0075] The first blowing port 151 is formed as a circular hole in the inner wall on the farthest side of the recess 38. When air is expelled from the first blowing port 151, air flow is generated along the side wall of the recess 38 and the air can be blown against the detection region 36 and in the vicinity of the cutter cutting blade 16.

[0076] The second blowing light 152 is formed as a slot and is arranged outside the recess 38. The second blowing light 152 is inclined with respect to the direction of the arrow in fig. 4, i.e. the direction of the groove-shaped recess width 38, and can blow air into the recess 38 in the diagonal direction to the direction of movement of the yarn. The air expelled from the second blowing port 152 is blown inside from the open side and from the upstream side of the movement of the yarn of the recess 38 and hits diagonally the side wall on one side of the recess 38, thus generating a flow of water. swirling air in the recess 38 and blowing air into the detection region 36 and the like.

[0077] Therefore, even if the foreign substances such as the fiber waste enters the recess 38 (detection region 36), the foreign substances can be blown away and expelled outside the recess 38 by expelling air from the first blowing light 151 and from the second blowing port 152.

[0078] Next, a configuration of the yarn clearer 15 will be described with reference to fig. 5 Fig. 5 is a block diagram illustrating an electrical configuration of the yarn clearer 15.

[0079] As shown in fig. 5, the yarn clearer 15 comprises the sensor unit 35 and a control section of the yarn clearer (control section) 50. The sensor unit 35 comprises an actuation circuit 40, the light projection section 41, the section of light reception 42, an amplifier 43, a high-pass filter 44, an amplifier circuit 45, a light indicator 46, the display device 47, the cutter 16 and an electromagnetic compressed-air valve 48.

[0080] The projection section of the light 41 comprises a light-emitting element configured by means of a light-emitting diode (LED). The projection section of the light 41 radiates light of the yarn 10 which slides through the yarn path with a quantity of light corresponding to an actuation voltage input coming from the driving circuit 40. The driving voltage generated by the driving circuit 40 is determined on the basis of an electrical signal input coming from a D / A converter 52 arranged in the control section of the yarn clearer 50.

[0081] The light receiving section 42 is disposed on the opposite side of the light projection section 41 with the recess 38 between them (i.e. with the yarn path passing through the recess 38 between them). The light receiving section 42 comprises a light receiving element configured by a photodiode and similarity. The light receiving section 42 receives a transmitted light of the light radiated from the projection section of the light 41 on the yarn 10 and emits the electric signal (voltage) corresponding to the quantity of light received. The electrical signal varies according to the shape (shape of the cross section) of the yarn 10 present between the projection section of the light 41 and the light receiving section 42.

[0082] The electrical signal emitted by the light receiving section 42 is amplified by the amplifier 43 and, subsequently, a signal of a predetermined high frequency is extracted by means of the high-pass filter 44 and again amplified by means of the amplifier circuit 45. Since the inversion process is carried out in the amplifier 43 of the present embodiment, the electric signal emitted by the amplifier 43 is reduced with the increase in the amount of light reception of the light receiving section 42. The amplified electric signal is emitted as a detection value from the sensor unit 35 and converted into a digital signal by means of an A / D converter 51 of the clearer control section 50.

[0083] The light indicator 46 can indicate to the operator the operating status of the yarn clearer 15 being on and off. In the present embodiment, the light indicator 46 is configured as a so-called two-color LED and can be illuminated with green and red. The lighting status of the indicator light 46 is controlled by the yarn clearer control section 50.

[0084] Therefore, the display device 47 can notify the operator of information relating to the operating status and similar status of the yarn clearer 15 by displaying characters, symbols, digits and the like. The displayed content of the display device 47 is controlled by the clearer control section 50.

[0085] The cutter 16 comprises the cutting blade, as described above, and the cutting blade is driven, for example, by a solenoid. The cutter 16 is electrically connected to the control section of the yarn clearer 50 and is configured to cut the yarn 10 based on a cutting signal emitted by the yarn-clearing control section 50.

[0086] The compressed-air electromagnetic valve 48 is arranged in a path between the source of compressed air supply (not shown) (for example, the blower of the yarn winding machine) and the first blowing port 151 and the second blowing light 152 described above. The compressed-air electromagnetic valve 48 is electrically connected to the control section of the yarn clearer 50 and is opened for a predetermined time based on an injection signal emitted by the control section of the yarn clearer 50 to inject air from the first blowing port 151 and the second blowing light 152. The first blowing light 151, the second blowing light 152 and the compressed air electromagnetic valve 48 configure a device for eliminating foreign substances suitable for eliminating foreign substances from the detection region 36.

[0087] In the present embodiment, the control section of the yarn clearer 50 performs the control for opening the compressed-air electromagnetic valve 48 to inject the air from the first blowing port 151 and from the second blowing port 152 immediately after the section Control unit 30 has started the yarn splicing cycle. At the beginning of the yarn splicing cycle, the yarn 10 is not introduced into the detection region 36 and, therefore, the air is injected with a timing such as to prevent the yarn 10 from inhibiting the air flow. Therefore, the foreign substances present in the detection region 36 can be blown off and eliminated effectively.

[0088] The control section of the yarn clearer 50 stores in the storage section 57, which will be described later, an evaluation reference value which is obtained starting from the detection value emitted by the sensor unit 35 when the yarn 10 is not present in the detection region 36. The yarn state evaluation section 53 disposed in the yarn-clearer control section 50 compares the evaluation reference value with the detection value to evaluate (measure) the state of the yarn 10.

[0089] A description will subsequently be given of an electrical configuration of the control section of the yarn clearer 50. The control section of the yarn clearer 50 comprises the yarn state evaluation section (evaluation section) 53, an adjustment section (section of adjustment of the light projection) 54, an acquisition section 55, a section for determining the presence / absence of the yarn 56, a data storage section 57, a setting section 58 and a process section for responding to foreign substances 59. Specifically, the control section of the yarn clearer 50 is configured as a computer comprising hardware, such as CPU, ROM and RAM, and software, such as a control program stored in ROM. Through the cooperation of hardware and software, the control section of the yarn clearer 50 can function as an evaluation section of the state of yarn 53, adjustment section 54, acquisition section 55, section for determining the presence / absence of yarn 56, section of data storage 57, setting section 58, process response section for foreign substances 59 and the like.

[0090] After a short time has elapsed since the start of the yarn splicing cycle and the injection of the air from the first blowing port 151 and from the second blowing port 152, the adjustment section 54 performs the adjustment process. (light projection adjustment process). The adjustment process is a process for adjusting an actuation voltage to be applied to the projection section of the light 41 in the sensor unit 35 so that the detection value (specifically, the output voltage) emitted by the unit of sensor 35 coincides with a predetermined adjustment reference value in a state in which the yarn 10 is not present in the detection region 36 of the yarn clearer 15.

[0091] The acquisition section 55 performs the measurement process. The measurement process is a process for controlling the sensor unit 35 so that the voltage regulated by the adjustment process is applied to the light projection section 41 and to acquire the detection value actually emitted by the sensor unit. 35 in a state in which the yarn 10 is not present in the detection region 36 of the yarn clearer 15. It is assumed that the detection value (specifically, the output voltage of the sensor unit 35) obtained in this manner is a value substantially equal to the adjustment reference value in the adjustment process but can be a divergent value, for example due to the influence of the thermal drift, of the entry and exit of fiber waste (foreign substances) and the like. The detection value acquired by the acquisition section 55 is stored in the data storage section 57 which will be described later.

[0092] The section for determining the presence / absence of the yarn 56 determines whether the yarn 10 is present in the detection region 36 (in particular, a yarn path in the detection region 36) of the yarn clearer 15 and whether the yarn 10 is introduced in the detection region 36 (in particular, a yarn path in the sensing region 36) based on the detection value acquired by the acquisition section 55. Specifically, the section for determining the presence / absence of yarn 56 determines that the yarn 10 is present in the yarn path (the yarn is present) if the emitted voltage of the sensor unit 35 is greater than or equal to a predetermined threshold value (threshold value for determining the presence / absence of the yarn) and determines that the yarn 10 is not present in the yarn path (the yarn is absent) if the emitted voltage is not greater than or equal to the predetermined threshold value. The detection region 36 is a space having a predetermined size. The yarn path in the sensing region 36 can be represented as a position where the yarn 10 moves, the position being regulated by a pair of upper and lower yarn path guides (not shown) 131, 132 (position of a point in the plane view: predetermined position).

[0093] If it is determined that the yarn is present, the determination section of the presence / absence of the yarn 56 (yarn clearing control section 50) sends to the control section of the unit 30 a signal which notifies that the yarn is present ( yarn presence signal). The control section of the unit 30 determines whether the yarn 10 is normally set in the detection region 36 by means of the yarn splicing cycle based on whether or not the yarn presence signal is emitted from the yarn clearer control section 50 However, the emission of the yarn presence signal of the yarn presence / absence determination section 56 may not be performed and the details of this circumstance will be described later.

[0094] The data storage section 57 has a storage region in which the content can be updated and, for example, is realized by means of a rewritable volatile or non-volatile memory (for example, RAM and EEPROM) and the like. The data storage section 57 can store various parameters and the like to control the yarn clearer 15.

[0095] Specifically, the data storage section 57 can store a plurality of measurement values obtained by the acquisition section 55. This means that the acquisition section 55 repeatedly performs, for a plurality of times, a measurement process for each predetermined time interval until the yarn 10 is introduced into the yarn path in the detection region 36 of the yarn clearer 15 (the position of the yarn 10 is within the yarn path: positioning) instead of performing the measurement process only once , and acquires the detection value each time. The data storage section 57 can store the data of the detection value for a predetermined number of times in the order of time series as the candidate value for the evaluation reference value, which will be described later.

[0096] The data storage section 57 can store an interval for determining the foreign substances defined to detect the entry and exit of the fiber and similar waste (foreign substances) with respect to the detection region, and a reference value which is a reference of the range of determination of the foreign substances when the yarn 10 is present in the detection region 36 of the yarn clearer 15. The range of determination of the foreign and similar substances will be described in detail with reference to the graph of fig. 6 and the like.

[0097] Furthermore, the data storage section 57 can store an upper limit value and a lower limit value of a normal range indicating an interval in which the detection value normally returns when the yarn 10 is not present in the detection region 36 of the clearer 15. The upper limit value and the lower limit value of the normal range are preset threshold values and the normal range is defined by the threshold values. The normal range is defined so that the width is greater than the width of the range of determination of foreign substances.

[0098] Furthermore, the data storage section 57 can store the threshold value for determining the presence / absence of the yarn which is the threshold value used as a border for the section for determining the presence / absence of yarn 56 to determine the presence / absence of yarn 10. A value greater than the upper limit value of the normal range is set for the threshold value for determining the presence / absence of the yarn.

[0099] The data storage section 57 can furthermore store a set value of the evaluation reference value determined by the setting section 58 which will be described below. The yarn state evaluation section 53 evaluates the status of the yarn 10 by comparison with the evaluation reference value. Specifically, an average value of the difference between the voltage set for the evaluation reference value and the voltage obtained from the sensor unit 35 with the yarn 10 in the detection region 36 of the yarn clearer 15 is used for monitoring the yarn 10 ( for example, calculation of the average thickness of the yarn 10).

[0100] The setting section 58 determines (calculates) the value of the evaluation reference value on the basis of the detection value which satisfies a predetermined condition between detection values (candidate value for the evaluation reference value) obtained from the section of acquisition 55 and stored in storage section 57, and stores the result in the data storage section 57 as a new set value. In the present embodiment, the memorization of the new set value of the evaluation reference value in the data storage section 57 is called "reference correction".

[0101] Subsequently a description will be given of two factors which reduce the accuracy of yarn evaluation (yarn monitoring accuracy) of the sensor unit 35 of the present embodiment. One of the two factors is the environmental change represented by the thermal drift and the like of the LED used by the light projection section 41, and the other factor is the entry of foreign substances into the detection region 36.

[0102] The details will be described later. As illustrated in the present embodiment, generally the following preparation operation is carried out before starting the evaluation of the yarn 10 in the yarn clearer 15 comprising the adjustment section 54, the acquisition section 55 and the setting section 58. This means that, in a state in which the yarn 10 is not present in the detection region 36, first the adjustment section 54 correctly adjusts the projection quantity of the light of the projection section of the light 41 of the sensor unit 35 by means of the adjustment process. Subsequently, the acquisition section 55 acquires the detection value of the sensor unit 35 and the setting section 58 sets the evaluation reference value based on the detection value in a state in which the yarn 10 is not present in the region of detection 36.

[0103] Once the preparation operation is completed, the yarn 10 is introduced into the detection region 36, the yarn winding unit 1 starts the winding and the state of the yarn 10 is evaluated by the state evaluation section of the yarn 53. In this case, the projection section of the light 41 is operated with the actuation voltage just adjusted in the preparation operation and an evaluation reference value set in the preparation operation is used for the yarn evaluation reference. 10. Thanks to the aforementioned control, it is possible to increase the accuracy of evaluation of the state of the yarn 10.

[0104] However, environmental characteristics such as temperature and humidity may vary during the period between the execution of the adjustment process and the setting of the evaluation reference value, until the yarn 10 is actually introduced into the detection region. 36. In particular, the yarn clearer 15 of the present embodiment is of the optical type and the projection section of the light 41 is configured by means of an LED. Therefore, for example, immediately after switching on the yarn clearer 15, the temperature of the LED can increase from the time instant in which the adjustment process is performed and the evaluation reference value is set at the time instant in which the yarn 10 is introduced into the sensing region 36, and the amount of light radiated by the projection section of the light 41 can vary due to such temperature variation (thermal drift) of the LED.

[0105] Also when the adjustment process is performed and the evaluation reference value is set again, if the light quantity of the light projection section 41 has changed with respect to this setting until the yarn 10 is introduced into the region of detection 36, an error occurs in the evaluation of the state of the yarn 10 due to this quantity and this is not desirable. Therefore, it is assumed that the acquisition of the detection value to define the evaluation reference value is performed not immediately after the adjustment process but with a timing immediately before the introduction of the yarn 10 in the detection region 36. In this way it is possible to reduce the influence of thermal drift and the like and perform an accurate yarn evaluation.

[0106] However, even if the timing of the determination of the evaluation reference value is expected to reduce the influence of the thermal drift and the like, this is not considered sufficient. This means that it is necessary to take into account the possibility that foreign substances such as fiber waste generated in the yarn winding machine enter the detection region 36.

[0107] For example, when the foreign substances enter the detection region 36 after the adjustment process has been carried out, the detection value emitted by the sensor unit 35 after the entry of the foreign substances is influenced by the foreign substances, and therefore it is not possible to accurately evaluate the state of the yarn 10. When the adjustment process is carried out in a state in which the foreign substances have already entered the sensing region 36, the detection value of the sensor unit 35 is affected. if subsequently the foreign substances leave the detection region 36, and therefore it is not possible to accurately assess the state of the yarn 10.

[0108] In this regard, in the yarn clearer 15 of the present embodiment, the entry of foreign substances into the sensing region 36 and the exit of the foreign substances entered from the sensing region 36 are detected from when the regulation process is performed. when the yarn 10 is introduced into the detection region 36 to carry out different types of process (hereinafter also referred to as the "foreign substance response process").

[0109] When the foreign substances enter the sensing region 36 or when the foreign substances leave the sensing region 36, the detection value varies relatively drastically. When the light amount of the light projection section 41 is reduced due to thermal drift, the detection value varies relatively gradually. The yarn clearer 15 of the present embodiment uses this fact to clearly distinguish the change (input / output) of the input state of the foreign substances from the thermal drift and detect the change (input / output) of the input state of the foreign substances.

[0110] A detailed description of the control of the control section of the yarn clearer 50 of the present embodiment in various cases will be given below, with reference to the graphs of Figures 6 to 10.

[0111] As described above, after the adjustment section 54 has carried out the adjustment process, the acquisition section 55 acquires in an iterative way the detection value with appropriate time intervals until the introduction of the yarn 10 is detected in the yarn path of the sensing region 36. In the graph of FIG. 6, the horizontal axis indicates the time and the vertical axis indicates the detection value, and the detection values acquired at each time from ti to t25 are illustrated. Furthermore, the graph of fig. 6 illustrates the range of determination of the foreign substances, the normal range and the threshold value for determining the presence / absence of the yarn.

[0112] The acquisition section 55 repeats the acquisition of the detection value in a time ti, a time t2 and so on. The obtained detection values are stored in sequence in the data storage section 57 as candidate values for the evaluation reference value.

[0113] In ti, which is the first acquisition time after completion of the adjustment process, the acquired detection value is stored in the data storage section 57 as a reference value defining the interval for determining the foreign substances, which will be described later.

[0114] The foreign substances response process section 59 sets the range of determination of the foreign substances, which is the interval in which the detection value acquired subsequently (within t2) will return, based on the reference value. The range of determination of the foreign substances is an interval set to detect the entry of foreign substances into the detection region 36 and the output of the foreign substances from the detection region 36, and is defined with the reference value described above as value central.

[0115] When the acquisition section 55 acquires the detection value in the time t2, the process section of response to the foreign substances 59 determines whether the value obtained in this time falls within the range of determination of the foreign substances. In the example of fig. 6, the detection value in time t2 is greater than or equal to the lower limit value and less than or equal to the upper limit value of the determination range of foreign substances by taking the detection value (reference value) over time as a reference. Therefore, subsequently the process section of response to the foreign substances 59 again stores the detection value in the time t2 in the data storage section 57 as a reference value, sets again the interval for determining the foreign substances on the basis of the new reference value and determines whether the detection value in time t3 falls within the range of determination of foreign substances. The determination processes of the above are iterated for a time t4, a time t5 and so on and consequently also the interval of determination of the foreign substances is updated in sequence.

[0116] In addition to the determination based on the range of determination of foreign substances, other determinations are made with respect to the individual detection values. Specifically, the adjustment section 54 determines whether the detection value falls within a normal range previously defined as an interval that usually takes the detection value in a state in which the yarn 10 is not present in the detection region 36 with respect to the value acquired in each time. The determination section of the presence / absence of the yarn 56 determines whether the detection value is greater than or equal to a predetermined threshold value for determining the presence / absence of the yarn with respect to the detection value acquired in each time. Generally, the normal range described above is set to include in its interior 1 determinazione range of determination of foreign substances, but the interval of determination of foreign substances can be outside the normal range. The threshold value for determining the presence / absence of the yarn is set to a value outside the range of determination of foreign substances.

[0117] Finally the yarn 10 is introduced into the detection region 36, so that the detection value acquired by the acquisition section 55 increases considerably over time t25. Since the detection value obtained at time t25 is higher than the threshold value for determining the presence / absence of the yarn, the determination of the presence / absence of yarn 56 determines that the yarn 10 is introduced into the detection region 36 (the yarn is present). In this case, the setting section 58 sets the detection value (in the example of Fig. 6, the detection value in time t24) acquired immediately before the time instant in which the presence of the yarn is determined, as a value of evaluation reference. When the reference correction is performed in the way described above and the movement of the yarn 10 is then started, the evaluation section of the state of the yarn 53 performs the evaluation of the yarn 10 based on the set evaluation reference value.

[0118] In the example of fig. 6, the detection value has a tendency to a gradual increase due to the influence of the thermal drift of the projection section of the light 41 described above, although this influence is not strong enough to cause the detection value to go out of the illustrated normal range in fig. 6 With this influence, a divergence of a certain magnitude is generated between the detection value in ti, which is the time immediately following the adjustment process, and the detection value in t24, which is the time immediately preceding the determination of the presence of the yarn. In this regard, the setting section 58 of the present embodiment uses the detection value in the time t24 close to the time in which the presence of the yarn is determined as an evaluation reference value, and therefore it is possible to reduce the influence of the thermal drift and accurately evaluating the yarn 10 by means of the yarn state evaluation section 53.

[0119] However, the valuation reference value is not limited to the detection value in time t24. For example, as the evaluation reference value it is possible to use the detection value in the time instant corresponding to a predetermined margin preceding the time instant in which the presence of the yarn is determined or it is possible to calculate an average value based on a plurality of detection values and use it as a valuation reference value.

[0120] Next, a description will be given of a case in which the detection value presents a transition such as that shown in Fig. 7 In the example of fig. 7, the detection values in the times from ti to t3 vary very little but, as a result of the entry of foreign substances into the detection region 36 from t3 to t4, the detection value in time t4 increases less | [Abruptly and exceeds the upper limit value of the range of determination of foreign substances based on the detection value (reference value) in time t3.

[0121] Similarly to fig. 6, also in the case of fig. 7, the acquisition section 55 repeats the acquisition of the time sensing values ti, time t2 and so on and stores in sequence the detection values obtained in the data storage section 57 as candidate values for the evaluation reference value. The update of the reference value and the interval for determining the foreign substances is performed in a similar way to the case of fig. 6

[0122] Since the detection value in time t4 is higher than the upper limit value of the range of determination of the foreign substances, the process section of response to the foreign substances 59 stops the updating of the reference value and of the determination interval of foreign substances. Therefore, it is determined whether the detection value in the following time t5 falls within the range of determination of the foreign substances taking as reference the detection value (reference value) in time t3 instead of time t4.

[0123] If the detection value is outside the range of determination of the foreign substances as in time t4, the detection value is not stored in the data storage section 57 as a candidate value for the evaluation reference value e, therefore, it will not be used in the future as a valuation benchmark. Therefore, it is possible to reliably prevent an abruptly modified irregular detection value from being adopted as a valuation reference value.

[0124] As long as the foreign substances continue to remain in the detection region 36, the detection value in time t5 does not vary much from the detection value of t4 and is higher than the upper limit value of the determination range of the foreign substances on the basis of detection value (reference value) in time t3, and also the detection values in time t6, in time t7 and in subsequent times are higher than the upper limit value. In the time t22, in which this state continues for a predetermined time (time of determination of the foreign substances), the process section of response to the foreign substances 59 determines that the foreign substances have entered the detection region 36 (high probability that the accuracy of yarn evaluation is reduced due to the influence of foreign substances).

[0125] Subsequently, the yarn 10 is introduced into the detection region 36 and the detection value increases considerably so as to be greater than or equal to the threshold value for determining the presence / absence of the yarn in time t25, similarly to the case of FIG. . 6 The section for determining the presence / absence of the yarn 56 determines that the yarn is present, but the process section of response to the foreign substances 59, which determines that the foreign substances have entered, prevents the section for determining the presence / absence of the yarn 56 to issue the yarn presence signal. Consequently, the section for determining the presence / absence of yarn 56 (yarn clearing control section 50) does not emit the yarn presence signal.

[0126] The control section of the unit 30 which oscillates the first yarn-catching device 12 and the second yarn-catching device 13 from the state of fig. 1 in the state of fig. 3 is configured to verify that the yarn 10 is introduced into the detection region 36 of the yarn clearer 15 on the basis of the yarn presence signal emitted by the yarn clearing control section 50. Even if the yarn 10 is actually introduced into the detection region 36, the process section of response to the foreign substances 59 does not induce the determination section of the presence / absence of the yarn 56 to emit the yarn presence signal (that is to say that the control section of the yarn clearer 50 operates as if the yarn 10 does not was introduced into the detection region 36).

[0127] Since the yarn presence signal is not emitted by the yarn-clearer control section 50 even after waiting for a predetermined time, the control section of the unit 30 determines that the introduction of the yarn 10 with respect to the region of detection 36 of the yarn clearer 15 was unsuccessful, for example due to the failure to capture the yarn 10 by means of the first yarn capture device 12 and the second yarn capture device 13. Therefore, the control section of the unit 30 cancels the operation without carrying out the yarn splicing operation by means of the yarn junction device 14, after having brought back the first yarn capture device 12 and the second yarn capture device 13 in the state of fig. 1, and executes the yarn splicing cycle again. Therefore, the yarn clearer 15 can avoid starting the winding of the yarn 10 in a state in which the yarn clearer 15 cannot accurately carry out the evaluation of the yarn under the influence of the foreign substances.

[0128] At the beginning of the yarn splicing cycle which has been carried out again, the control section of the yarn clearer 50 actuates the compressed air solenoid valve 48 and the process (elimination of foreign substances) of air injection from the first is performed. blowing light 151 and the second blowing light 152. Thus, the foreign substances entering the sensing region 36 have a high possibility of being blown away by air and, therefore, it is expected that the foreign substances will not adversely affect the subsequent adjustment process and setting of the evaluation reference value.

[0129] After the injection of air capable of removing the foreign substances from the detection region 36, in the control section of the yarn clearer 50, the adjustment section 54 again performs the adjustment process, after which the acquisition section 55 acquires again iteratively the detection value of the sensor unit 35. If the detection value shows the transition illustrated in fig. 6 and the yarn 10 is introduced into the sensing region 36 in this case, the evaluation reference value is defined as described above and the evaluation section of the state of the yarn 53 evaluates the yarn 10 using this evaluation reference value.

[0130] Accordingly, in the yarn clearer 15 of the present embodiment, when it is determined that the foreign substances have entered the detection region 36 based on the behavior of the detection value emitted by the sensor unit 35, the response process section to the foreign substances 59 performs the process (process of response to the foreign substances) to prevent the section for determining the presence / absence of the yarn 56 from emitting the signal of presence of the yarn relating to the determination of the presence of the yarn. Consequently, the yarn splicing cycle is performed again and, consequently, the detection region 36 is cleaned by expelling air from the first blowing port 151 and from the second blowing port 152, and the new adjustment of the light projection quantity by means of the adjustment section 54 (therefore, the reference adjustment is also performed again).

[0131] Therefore it can be stated that the process section of response to foreign substances 59 substantially performs the elimination of foreign substances by expelling air from the first blowing port 151 and from the second blowing port 152 and the new regulation of the amount of light projection. Consequently, it is possible to satisfactorily avoid the negative effect of the foreign substances on the regulation of the light projection quantity and on the reference correction and the evaluation section of the state of the yarn 53 can accurately assess the state of the yarn 10.

[0132] Next, a description will be given of a case in which the detection value presents a transition such as that shown in fig. 8 In the example of fig. 8, the detection value in time t4 increases less: [A2] abruptly and the detection value in time t5 is substantially the same as the time t4, but the detection value in time t6 is reduced to a value substantially equal to t3. This indicates that the foreign substances enter the detection region 36 between t3 and t4 but they exit between t5 and t6 without remaining inside for a long time.

[0133] To describe the transition of the detection values in relation to the range of determination of the foreign substances, the detection value in time t4 is higher and also the detection value in time t5 is similarly higher than the upper limit value of the interval for determining the foreign substances defined with the detection value at time t3 as a reference, but the detection value at time t6 is greater than or equal to the lower limit value and less than or equal to the upper limit value of the determination range of foreign substances. This means that the time in which the upper limit value of the range of determination of foreign substances is exceeded continuously is less than the time of determination of foreign substances (see fig. 7). Therefore, in this case, the process response section to foreign substances 59 does not cause the entry of foreign substances (high possibility that the accuracy of the yarn evaluation is reduced due to the influence of foreign substances).

[0134] As described above, the detection value in time t6 is greater than or equal to the lower limit value and lower than or equal to the upper limit value of the determination range of the foreign substances, taking the detection value (reference value) in the time t3 as a reference. Therefore, the foreign substances response process section 59 sets the detection value in time t6 as a new reference value, redefines again the determination range of the foreign substances so that the reference value becomes a reference and updates the stored content of the data storage section 57 in relation to the reference value and the interval for determining the foreign substances. The detection values in times t4 and t5 are outside the range of determination of the foreign substances and, therefore, they are not stored in the data storage section 57 as candidate values for the evaluation reference value, but the detection value is stored in the data storage section 57 in time t6, when the detection value returns to the range of determination of the foreign substances. Subsequently, the foreign substance response process section 59 monitors whether there is again a sharp fluctuation (i.e. the output fluctuation from the range of determination of foreign substances) of the detection value.

[0135] In the example of fig. 8, the detection value does not change much after the time t6 up to the introduction of the yarn 10 into the sensing region 36. When the yarn 10 is introduced into the sensing region 36 and the detection value increases very much so that it is higher or equal to the threshold value for determining the presence / absence of the yarn in time t25, the section for determining the presence / absence of yarn 56 determines that the yarn is present. Since the process section of response to the foreign substances 59 does not cause the entry of the foreign substances, the section for determining the presence / absence of the yarn 56 normally emits the yarn presence signal and the setting section 58 sets the detection value. in time t24 as a valuation reference value. Subsequently, with the start of the winding of the yarn 10, the evaluation section of the state of the yarn 53 monitors the yarn 10.

[0136] Therefore, when the foreign substances enter the detection region 36 but leave the sensing region 36 after a short time, it is hypothesized that the foreign substances did not enter and, therefore, the process of response to the foreign substances through the process of response to foreign substances 59 is not performed and the normal process is performed. Therefore, the execution of a useless process of response to foreign substances is prevented and it is possible to increase the efficiency of the yarn winding machine.

[0137] The phenomenon whereby the detection value increases sharply but returns after a short time to its original value as in fig. 8 may depend on factors other than foreign substances. For example, in the doffing operation, the doffing operation can be performed normally but the detection value of the sensor unit 35 can become very unstable and may temporarily go out of the range of determination of the foreign substances. However, in the doffing operation, this variation does not continue for a long period, unlike the determination time of the foreign substances, and in most cases the changed detection value returns to its original value in a short time. Therefore, it is possible to prevent the execution of the process of response to foreign substances during the normal doffing operation, which also increases the efficiency of the yarn winding machine.

[0138] Next, a description will be given of a case in which the detection value presents a transition such as that shown in fig. 9 The example in fig. 9 illustrates a case in which the influence of the thermal drift of the projection section of the light 41 is strong and the detection value has a greater tendency to increase with respect to the case of Fig. 6 immediately after the adjustment process. The amount of increase in the detection value at each time is within the range of determination of foreign substances.

[0139] Finally, the increased detection value for each acquisition exceeds the upper limit value of the normal range. The regulation section 54, detecting that the detection value acquired in time tl9 is higher than the upper limit value of the normal interval, performs the adjustment process again. As a result, the measurement process and the reference correction are performed again after the adjustment process is completed.

[0140] With the process described above, when an unacceptable thermal drift occurs, the adjustment process can be performed again by the adjustment section 54. This means that the state of the yarn 10 can be accurately evaluated by regulating the tension again operating the light projection section 41 to eliminate the influence of thermal drift.

[0141] In the example described above, when the detection value is higher than the upper limit value of the normal interval even once, the adjustment process is performed again. Alternatively, the adjustment section 54 can re-execute the adjustment process when the detection value is continuously higher for a predetermined adjustment determination time (time to determine the light projection adjustment). In this case, for example, it is possible to prevent the adjustment process being performed unnecessarily due to the noise present in the detection value.

[0142] The increase in the detection value due to the thermal drift as shown in fig. 9 has different characteristics with respect to the increase in the detection value due to the entry of foreign substances shown in figs. 7 and 8. This means that when the detection value increases due to the influence of the thermal drift, the amount of increase compared to the detection value in the previous time is relatively small and regular compared to the case in which the foreign substances enter and, therefore, is less it is probable that the detection value goes outside the range of determination of the foreign substances until the time interval for the acquisition of the detection value is sufficiently short. In fact, in the example of fig. 9, the single detection value until the detection value exceeds the upper limit value of the normal interval in time tl9 does not go outside the range of determination of the foreign substances even once and, therefore, the process section in response to foreign substances 59 does not determine that foreign substances have entered. Therefore, the process of response to foreign substances (process to inhibit the emission of the yarn presence signal) is not performed.

[0143] Therefore, in the present embodiment, when the detection value changes abruptly once and this state after the continuous variation for a predetermined time, the process section of response to the foreign substances 59 determines that the state of entry of the foreign substances has changed and executes the response process of foreign substances. Therefore it is possible to prevent the incorrect determination that the variation occurs not due to the influence of the thermal drift but to the foreign substances and the useless execution of the process of response to foreign substances.

[0144] Next, a description will be given of a case in which the detection value presents a transition such as that shown in Fig. 10 In the example of fig. 10, which is the opposite case to fig. 7, the detection value in time t4 is lower than the lower limit value of the determination range of foreign substances, taking the detection value (reference value) in time t3 as a reference, a situation that continues for a long period of time. This is assumed since the adjustment process is carried out with the foreign substances entering the detection region 36 and subsequently the foreign substances remain in the detection region 36 up to the time t3 but leave the sensing region 36 between t3 and t4.

[0145] In this case, the foreign substance response process section 59 performs a process substantially similar to the case illustrated in Fig. 7 Specifically, since the detection value in time t4 is lower than the lower limit value of the determination range of foreign substances on the basis of the detection value (reference value) in time t3, the process section of response to foreign substances 59 stops the update of the determination interval of the foreign substances. Therefore, it is determined whether the detection value in the following time t5 falls within the range of determination of the foreign substances based on the detection value (reference value) in time t3.

[0146] In the example of fig. 10, the detection value in time t5 is also lower than the lower limit value of the determination range of foreign substances on the basis of the detection value in time t3, which continues for time t6, time t7 and subsequent times. The process section of response to the foreign substances 59 determines that the foreign substances have left the detection region 36 in the time t22 in which the relative state continues for a predetermined time (time of determination of the foreign substances). Therefore, similarly to the case illustrated in Figure 7, in which it is determined that the foreign substances have entered, the process section of response to the foreign substances 59 prevents the section for determining the presence / absence of the yarn 56 from emitting the presence signal of the yarn even if the yarn 10 is introduced into the detection region 36 and induces again the execution of the yarn splicing cycle. Therefore, since the adjustment process and the reference correction can be performed again with the exiting foreign substances, the evaluation section of the state of the yarn 53 can accurately assess the state of the yarn 10.

[0147] Subsequently, referring to the flow chart of Fig. 11, a description of a specific process performed by the adjustment section 54, by the acquisition section 55, by the section for determining the presence / absence of the yarn 56, by the setting section 58, by the process section for response to the foreign substances will be provided. 59 and similar of the clearer control section 50.

[0148] The adjustment process, the measurement process and the like illustrated in fig. 11 are carried out, instead of starting the yarn clearer 15, each time the yarn 10 is interrupted for some reason and disappears from the detection region 36 of the yarn clearer 15, and the yarn splicing operation described above is performed. A case in which the yarn 10 is interrupted comprises the case in which the yarn clearer 15 finds the yarn defect in the yarn monitoring and cuts the yarn 10 by means of the cutter 16, the case in which the cone 20 is completely wound and the yarn 10 it is cut by the cutter 16 and the like, and the case in which a yarn break has occurred.

[0149] Since the adjustment process and the measurement process are performed frequently as described above, the yarn 10 can be monitored in a stable manner independently of a change in the surrounding environment, from an attack of contaminants in the light projection section 41, in the light receiving section 42 and similar of the yarn clearer 15, and the like. Furthermore, as described above, the air from the first blowing port 151 and from the second blowing port 152 is injected at the beginning of the yarn splicing cycle and the process of FIG. 11, in such a way that it is possible to prevent the execution of the regulation process, the measurement process and the like with the foreign substances entering the detection region 36.

[0150] If the process of fig. 11 is started without the yarn 10 being present in the detection region 36 of the yarn clearer 15, first the adjustment process is carried out by the adjustment section 54 and the actuation voltage of the projection section of the light 41 in the sensor unit 35 it is adjusted as described above (step S101). After completion of the adjustment process, an initialization process is performed to indicate an input change indicator for foreign substances to "0" (step S102). Immediately afterwards, the iterative acquisition process (phases S103 to SUO) of the detection values is started using the acquisition section 55.

[0151] Specifically, the acquisition section 55 controls the sensor unit 35 so as to apply the actuation voltage regulated by the adjustment process on the projection section of the light 41 and acquires the detection value actually emitted by the unit of sensor 35 (measurement process described above, step S103). Subsequently, the section for determining the presence / absence of the yarn 56 determines whether the detection value acquired by the acquisition section 55 is greater than or equal to the threshold value for determining the presence / absence of the yarn (step S104). If the detection value is lower than the threshold value for determining the presence / absence of the yarn, the adjustment section 54 determines whether the detection value is within the normal range, ie if the detection value is higher than the limit value lower and lower than the upper limit of the normal range (step S105). If the detection value is greater than or equal to the upper limit value of the normal range, it is assumed that an unacceptable thermal drift has occurred and the process returns to phase S101. Consequently, the adjustment section 54 regulates the amount of light projection again and the subsequent processes are performed again.

[0152] When the detection value is higher than the lower limit value and lower than the upper limit value of the normal range in the determination of the step S105, the foreign substance response process section 59 determines whether the detection value is within the range of determination of foreign substances defined on the basis of the previous detection value (reference value) (phase S106). If the detection value falls within the range of determination of the foreign substances (ie, if it is greater than or equal to the lower limit value and less than or equal to the upper limit value of the determination range of the foreign substances), the process section of response to the foreign substances 59 stores the detection value obtained in this time in the data storage section 57 as a reference value and redefines again the determination range of the foreign substances on the basis of this reference value to store the interval in the section of data storage 57 (step S107). Moreover, the acquisition section 55 stores the detection value obtained in this time in the data storage section 57 separately from the reference value as candidate value to be used for setting the evaluation reference value (step S108).

[0153] If the detection value is outside the range of determination of foreign substances (ie, if it is less than the lower limit value or higher than the upper limit value of the range of determination of the foreign substances), in the determination of step S106, in step S109 the process section of response to the foreign substances 59 also determines whether the state in which the detection value is outside the range of determination of the foreign substances continues for a predetermined time (i.e. the determination time of foreign substances). If the state in which the detection value is outside the range of determination of the foreign substances continues for the time of determination of the foreign substances, the process section of response to the foreign substances 59 determines that the input has occurred or the exit of foreign substances, sets the indicator for changing the entry of foreign substances to «1» (phase SUO) and then returns to phase S103. If the time in which the status of the detection value is outside the interval of determination of foreign substances continues is less than the time of determination of the foreign substances in the determination of the phase S109, the process returns to phase S103 maintaining the indicator of change of the entry of foreign substances to «0» (skipping the phase SUO of setting the indicator of change of the entrance of foreign substances to «1»).

[0154] If the detection value is greater than or equal to the threshold value for determining the presence / absence of the yarn in the determination of step S104, the status of the change indicator of the entry of foreign substances (step S111) is examined. If the indicator of change in the entry of foreign substances is «0», this means that the process section of response to foreign substances 59 has not determined that the entry / exit of foreign substances has occurred. Therefore, in this case, the setting section 58 sets the evaluation reference value based on the detection value stored in the data storage section 57 in step S108 from the acquisition section 55 (step S112). Specifically, among the plurality of detection values stored in the data storage section 57 in the order of time series, the setting section 58 sets as the evaluation reference value the last detection value acquired immediately before the time in which it is received. having determined that the yarn is present, and the data storage section 57 stores the last detection value as an evaluation reference value. Subsequently, the section for determining the presence / absence of yarn 56 emits the yarn presence signal (step S113). The control section of the unit 30 which receives the yarn presence signal immediately executes the yarn splicing operation by means of the yarn junction device 14 as necessary, then starts the winding of the yarn 10 by means of the winding section 18 The evaluation section of the state of the yarn 53 evaluates the yarn 10 moving through the detection region 36 based on the value of the new evaluation reference value (step S114).

[0155] If the indicator of change of the entrance of foreign substances is «1» in the determination of the phase S111, this means that the process section of response to foreign substances 59 has determined that the entry / exit of the foreign substances. Therefore, the process section of response to the foreign substances 59 prevents the section for determining the presence / absence of the yarn 56 from emitting the yarn presence signal, which is normally emitted, and is stopped in this state (step S115). Consequently, the yarn clearer 15 functions as if the yarn 10 were not present although the yarn 10 is actually set and present (positioned) in the detection region 36. The control section of the unit 30 assumes that the introduction of the yarn 10 in the detection region 36 of the yarn clearer 15 has failed and re-executes the yarn splicing cycle since the yarn presence signal is not emitted even after waiting for a predetermined time. At the beginning of the newly started junction cycle, air is injected from the first blowing port 151 and from the second blowing port 152 and therefore, even if the foreign substances have entered the detection region 36, the foreign substances can be blown off and eliminated. Subsequently, the processes illustrated in the flow diagram of fig. 11

[0156] With the above processes, the evaluation section of the state of the yarn 53 of the yarn clearing control section 50 can satisfactorily eliminate the influence of the entry / exit of foreign substances and the influence of the thermal drift and similar to the projection section of the light 41 and can accurately assess the state of the yarn 10.

[0157] In the time instant in which the indicator of change of the entrance of the foreign substances is set to «1» (phase SUO) or in the time instant in which the section for determining the presence / absence of the yarn 56 is stopped without issuing the yarn presence signal (step S115), the light indicator 46 and the display device 47 are controlled to display the occurrence of the entry / exit of foreign substances. Therefore, the anomaly of the detection value caused by foreign substances can be notified to the operator in an easily understandable way.

[0158] The flow chart of fig. 11 illustrates that it is determined whether the detection value falls within the range of determination of the foreign substances in step S106, but is actually determined if the detection value is higher than the upper limit value of the range of determination of foreign substances, lower than the value lower limit of the determination range of the foreign substances either greater than or equal to the lower limit value and less than or equal to the upper limit value of the determination range of the foreign substances. If the detection value is higher than the upper limit value of the range of determination of the foreign substances, on the display device 47 the warning is displayed that the foreign substances have entered and, if the detection value is lower than the lower limit value of the range of determination of the foreign substances, on the display device 47 is displayed the warning that the foreign substances have come out. Therefore, it is possible to clearly notify the operator if the anomaly is due to the entry of foreign substances or if the anomaly is due to the exit of foreign substances.

[0159] The process of response to the foreign substances carried out by the process section of response to the foreign substances 59 in the present embodiment directly directly inhibits the emission of the yarn presence signal by the section for determining the presence / absence of the yarn 56, and the expulsion of air from the first blowing port 151 and from the second blowing port 152 as well as the new adjustment of the quantity of light projection are performed as a consequence of the inhibition of the emission of the signal of presence of the yarn (therefore, in the process of response to foreign substances, a signal to detect foreign substances is not issued as an input signal of foreign substances / signal output of foreign substances). However, even with this configuration, it can be recognized that the process section of response to foreign substances 59 substantially expels air and regulates the amount of light projection again. Evidently, the process of response to the foreign substances performed by the process section of response to the foreign substances 59 (control section of the yarn clearer 50) can be a process of sending a signal (signal requesting the elimination of foreign substances) to the electromagnetic valve with compressed air 48 to expel air into the sensing region 36. The process of responding to foreign substances can comprise a process capable of directly emitting a signal to induce the regulation section 54 to carry out the regulation process again after the elimination of the substances extraneous.

[0160] The process of response to foreign substances carried out by the process section of response to foreign substances 59 can be modified so as to emit the signal for detecting foreign substances in place or in addition to the inhibition of the emission of the presence signal of the yarn of the determination section of the presence / absence of yarn 56. For example, the process section of response to foreign substances 59 can transmit the input signal of foreign substances / output signal of foreign substances to the control section of the unit 30, and the control section of the unit 30 which receives this signal can cancel the yarn splicing operation by means of the yarn junction device 14 and re-execute the yarn splicing cycle (that is to say that resumption is inhibited winding).

[0161] The process of response to the foreign substances performed by the process section of response to the foreign substances 59 can comprise various processes, for example a process of emission of a signal to inhibit the winding to inhibit the start of the winding of the section winding 18. When the yarn splicing signal requiring the yarn splicing operation is emitted in the middle of the yarn splicing cycle, the control section of the unit 30 can be configured to re-start the cycle from the beginning. of yarn splicing, and the process section of response to the foreign substances 59 can carry out the process of sending the splice signal of the yarn to the control section of the unit 30 as a process for responding to foreign substances. Therefore there may be various responses in relation to the entry / separation of foreign substances.

[0162] As shown in fig. 12, the range of determination of foreign substances can be defined so that it becomes a fixed interval. In the example of the graph in fig. 12, the range of determination of the foreign substances is defined to have a predetermined width with the reference reference value in the adjustment process as a reference. In the alternative embodiment, the range of determination of the foreign substances does not change and is constant even if the detection value acquired by the acquisition section 55 varies. In the example of Figure 12, the normal range includes the range of determination of foreign substances and is set to be wider than the range of determination of foreign substances.

[0163] In the example of fig. 12, in which the range of determination of the foreign substances is defined to be a fixed interval, it is difficult to detect distinctly between the thermal drift and the entry / exit of foreign substances. However, when the thermal drift does not become a problem, for example when a sufficient time has elapsed from the lighting of the yarn clearer 15, and when the high-performance LED is used as a light projection section 41, the entry / exit of the substances strangers can be detected satisfactorily even if the determination of foreign substances is fixedly defined.

[0164] As described above, the yarn clearer 15 of the present embodiment comprises the projection section of the light 41, the light receiving section 42 and the control section of the yarn clearer 50. The light projection section 41 projects the light onto the sensing region 36 through which the yarn 10 flows. The light receiving section 42 receives the light projected from the projection section of the light 41 and emits an electrical signal corresponding to the amount of light reception. The detection value corresponding to the light receiving quantity of the light receiving section 42 is sent to the yarn clearer control section 50. The yarn clearer control section 50 comprises the yarn state evaluation section 53, the adjustment section 54 and the foreign substance response process section 59. The yarn state evaluation section 53 assesses the state of the yarn 10 present in the detection region 36 based on the detection value. The adjustment section 54 performs the adjustment process to adjust the drive control value of the light projection section 41 so that the detection value becomes a predetermined value in a state in which the yarn 10 is not present in the region of detection 36. The process section of response to foreign substances 59 performs the process of response to foreign substances when the detection value is outside a predetermined range of determination of foreign substances for a time of determination of the substances extraneous predetermined in a state where the yarn 10 is not present in the sensing region 36. The adjusting section 54 again performs the adjustment process when the detection value is outside a normal range, which is a value range pre-set detection time to have a wider range than the detection interval ion of the foreign substances, in a state in which the yarn 10 is not present in the detection region.

[0165] Therefore, if the detection value in a state in which the yarn 10 is not present in the detection region 36 is outside the range of determination of the foreign substances continuously for a predetermined time to determine the foreign substances , it is determined that the entry state of the foreign substances is changed, the predetermined response process to the foreign substances is performed and the process can be carried out in an appropriate manner in relation to the entry / separation of the foreign substances. In the condition in which, for example, the detection value is outside the range of determination of the foreign substances in a continuous manner for a predetermined time for determining the foreign substances, it is possible to prevent the entry status of the foreign substances from being erroneously determined as changed even if the detection value entered into the clearer control section 50 becomes unstable during the normal doffing operation.

[0166] In the yarn clearer 15 of the present embodiment, the adjustment section 54 can be configured to perform the adjustment process again when the detection value is outside the normal range continuously for a predetermined adjustment determination time. in a state in which the yarn 10 is not present in the detection region 36.

[0167] In this case, for example, it is possible to prevent the adjustment process being performed unnecessarily due to the noise present in the detection value.

[0168] Furthermore, the yarn clearer 15 of the present embodiment comprises the device for eliminating the foreign substances configured to comprise the first blowing port 151, the second blowing port 152 and the compressed air electromagnetic valve 48 to eliminate the foreign substances present in the detection region 36. The process of response to the foreign substances carried out by the foreign substance response process section 59 comprises the process of actuating the foreign substance elimination device.

[0169] Therefore, it is possible to eliminate the foreign substances of the detection region 36 and obtain a state suitable for the regulation process and the like.

[0170] Furthermore, in the yarn clearer 15 of the present embodiment, the device for eliminating foreign substances eliminates the foreign substances by blowing air into the sensing region 36.

[0171] Therefore, it is possible to eliminate the foreign substances present in the detection region 36 with a simple configuration.

[0172] Furthermore, in the yarn clearer 15 of the present embodiment, the process of response to the foreign substances carried out by the process response section to the foreign substances 59 comprises a process for inducing the adjustment section 54 to carry out the adjustment process again.

[0173] When the adjustment process is carried out again, the influence of the foreign substances with respect to the detection value can be effectively eliminated.

[0174] The yarn clearer 15 of the present embodiment comprises the section for determining the presence / absence of the yarn 56 able to determine whether the yarn 10 is present in the detection region 36. The process of response to the foreign substances carried out by the process section of response to the foreign substances 59 comprises a process for operating as if the yarn 10 were not present in the sensing region 36 even though the section for determining the presence / absence of the yarn 56 determines that the yarn 10 is present in the detection region 36.

[0175] This means that, when the process section of response to the foreign substances 59 determines that the foreign substances have entered or exited, the yarn clearer 15 cannot accurately assess the yarn 10 due to the influence of the foreign substances e, therefore, it is not appropriate to start winding in the yarn winding machine. Therefore, in this case, the yarn clearer 15 functions as if the yarn 10 were not set, so that, subsequently, it is possible to reliably prevent the start of the winding.

[0176] In the yarn clearer 15 of the present embodiment, the section for determining the presence / absence of the yarn 56 determines whether the yarn 10 is present in the yarn path in the detection region 36.

[0177] Therefore, the yarn clearer 15 can reliably detect whether the yarn 10 is present in the yarn path. Moreover, when the process section for responding to the foreign substances 59 determines that the foreign substances have entered or exited, the yarn clearer 15 can function as if the yarn 10 were not present in the yarn path.

[0178] The process of response to foreign substances carried out by the process section of response to foreign substances 59 can comprise at least one of a process of emission of a signal of foreign substances, a process of emission of a signal to inhibit the winding for inhibiting the start of the winding of the yarn 10 by means of the winding section 18 and a process of emission of the yarn junction signal to induce the yarn junction device to perform the splicing operation of the yarn.

[0179] Therefore, it is possible to perform various processes of response to foreign substances.

[0180] The yarn clearer 15 of the present embodiment comprises the light indicator 46 and the display device 47. The light indicator 46 and the display device 47 create a notification when the detection value is outside a range of determination of the foreign substances continuously for a time of determination of the foreign substances in a state in which the yarn 10 is not present in the detection region 36.

[0181] Therefore, the operator who uses the yarn winding machine (yarn winding unit 1) can recognize the entry and exit of foreign substances in / from the detection region 36 by means of the light indicator 46 and the display device 47. Furthermore, the operator can manually stop the winding of the yarn winding machine based on the notification.

[0182] In the yarn clearer 15 of the present embodiment, the display device 47 which warns the operator is configured as a display device capable of displaying at least one of characters, symbols and figures.

[0183] Therefore, it is possible to create a notification for the operator with a simple configuration. Furthermore, the detailed content can be notified to the operator by displaying characters and the like on the screen.

[0184] Moreover, in the yarn clearer 15 of the present embodiment, the light indicator 46 which warns the operator is configured as a lamp that can be turned on.

[0185] Therefore, a notification can be created for the operator with a simple configuration. A state relating to foreign substances can be notified by the state of ignition of the light indicator, so that the operator can easily check the entry / exit of foreign substances even from a remote location.

[0186] Moreover, in the yarn clearer 15 of the present embodiment, when a state in which the detection value is outside the determination of the foreign substances beyond the upper limit value of the range of determination of the foreign substances continues for a predetermined time ( specifically, the determination time of the foreign substances), as shown in fig. 7, in a state in which the yarn 10 is not present in the detection region 36, the process section of response to the foreign substances 59 determines that the foreign substances entered the sensing region 36. When a state in which the value of detection is outside of the determination of the foreign substances beyond the lower limit value of the range of determination of the foreign substances continues for a predetermined time (specifically, the time of determination of the foreign substances), as shown in fig. 10, in a state in which the yarn 10 is not present in the detection region 36, the process section of response to the foreign substances 59 determines that the foreign substances have left the sensing region 36

[0187] Therefore, the process section of response to the foreign substances 59 can determine, in a distinct manner, the entry and exit of the foreign substances in and from the detection region 36.

[0188] In the clearer 15 of the present embodiment, the interval for determining the foreign substances is defined relatively with the reference value, which is a past detection value, as a reference. When the reference value is greater than or equal to the lower limit value and lower than or equal to the upper limit value of the range of determination of the foreign substances, the process section of response to the foreign substances 59 uses a new range of determination of the foreign substances defined with the relevant detection value as a reference value in the subsequent determination.

[0189] Therefore, the foreign substance response process section 59 may very accurately know whether the state of entry of the foreign substances into the detection region 36 has changed.

[0190] The determination range of the foreign substances can be defined in a fixed manner as shown in the example of fig. 12

[0191] In this case, it is possible to easily determine the entry / exit of foreign substances.

[0192] The yarn clearer 15 of the present embodiment comprises the section for determining the presence / absence of the yarn 56 designed to determine whether the yarn 10 is present in the detection region 36. The determination of the presence / absence of yarn 56 determines that the yarn 10 is present in the detection region 36 when the detection value is greater than or equal to the threshold value for determining the presence / absence of the yarn. The threshold value for determining the presence / absence of the yarn is set to a value outside the range of determination of foreign substances.

[0193] Therefore, the yarn clearer 15 can know of the presence of the yarn 10 in a manner distinct from foreign substances such as fiber waste.

[0194] The preferred embodiments of the present invention have been described above; the configurations described above can be modified as described below.

[0195] The foreign substance response process performed by the foreign substance response process section 59 can be differentiated between the determination that the foreign substances entered the detection region 36 and the determination that the foreign substances left the region of detection 36. For example, air is injected from the first blowing port 151 and from the second blowing port 152 to eliminate foreign substances in the case of fig. 7 in which the foreign substances enter, and the air injection is not performed in the case of fig. 10 in which the foreign substances come out.

[0196] The configuration of air blowing in the detection region 36 is not limited to the configuration described above. For example, it is possible to omit the first blowing light 151 or the second blowing light 152. It is possible that the air expulsion light is not made in the housing 37 and that an air nozzle is provided at the distal end of a suitable pipe installed on the outside, so that the air is injected into the recess 38 by the air nozzle.

[0197] The foreign substances can be eliminated without the use of air, for example it is possible to provide a device for eliminating foreign substances suitable for cleaning by inserting a thin brush in the recess 38 formed in the housing 37 of the yarn clearer 15.

[0198] Moreover, it is possible to omit the configuration for the elimination of foreign substances and provide for the manual elimination of foreign substances from the recess 38 by the operator induced by the light indicator 46 and the display device 47. It is possible do not install the display device 47.

[0199] In the embodiment described above, the entry / exit of the foreign substances with respect to the detection region 36 is determined by using the light receiving section 42 adapted to receive the transmitted light, which is the light that is emitted by the projection section of the light 41 towards the yarn 10 and passing through the yarn 10. However, the entry / exit of the foreign substances with respect to the sensing region 36 can be determined by using the light receiving section to receive the reflected light. , which is the light which is emitted from the projection section of the light 41 towards the yarn 10 and which is reflected by the yarn 10.

[0200] In the embodiment described above, the yarn clearer 15 comprises the cutter 16, and the yarn 10 can be cut when the yarn defect is detected. However, it is possible to adopt a yarn monitoring device which does not comprise the cutter 16. This means that the monitoring device of the present invention can be a device that only monitors the state of the yarn.

[0201] In the embodiment described above, the inversion process is performed by the amplifier 43 arranged behind the light-receiving section 42. Consequently, the greater the light-receiving quantity of the light-receiving section 42, the smaller will be the output voltage of the amplifier 43. However, it is possible to use an amplifier that does not perform the inversion process. In this case, the vertical axis in the graphs shown in Figures 6 to 10 and in Fig. 12 is inverted, so that the relation of the magnitude of the detection value is reversed in the determination relative to the entry / separation of the foreign substances, to the normal interval and to the presence / absence of the yarn.

[0202] The yarn winding machine is not limited to the spinning machine and the automatic winder and can be a yarn winding machine which has other configurations.

Claims (16)

1. A yarn monitoring device (15) comprising: a light projection section (41) adapted to project light onto a sensing region (36) through which a yarn (10) slides; a light receiving section (42) adapted to receive the light projected from the light projection section (41); is a control section (50) to which a detection value is sent corresponding to a light receiving quantity of the light receiving section (42), characterized in that the control section (50) includes an evaluation section (53) for evaluating a state of the yarn (10) present in the detection region (36) based on the detection value, a light projection adjustment section (54) adapted to carry out a light projection adjustment process to adjust an actuation control value of the light projection section (41) so that the detection value becomes a value predetermined in a state in which the yarn (10) is not present in the detection region (36), and a foreign substance response process section (59) adapted to carry out a process of response to foreign substances when the detection value is outside a predetermined range of determination of foreign substances for a substance determination time predetermined extraneous in the state in which the yarn (10) is not present in the detection region (36), e the light projection adjustment section (54) again performs the light projection adjustment process when a detection value is outside a normal range, which is a preset detection interval range so as to have a greater width than the width of the determination range of foreign substances in the state in which the yarn (10) is not present in the detection region (36). 2. A yarn monitoring device (15) according to claim 1, characterized in that the light projection adjustment section (54) again performs the light projection adjustment process when the detection value is outside of the normal range in a continuous manner for a predetermined time of determination of light projection adjustment in the state in which the yarn (10) is not present in the detection region (36). 3. A yarn monitoring device (15) according to claim 1 or 2, characterized in that it further comprises: a device for removing foreign substances (151, 152, 48) able to remove foreign substances present in the detection region (36), in which the foreign substance response process carried out by the foreign substance response process section (59) comprises a process for actuating the foreign substance removal device (151, 152, 48). 4. A yarn monitoring device (15) according to claim 3, characterized in that the device for removing foreign substances (151, 152, 48) removes foreign substances by blowing air into the sensing region (36). 5. A yarn monitoring device (15) according to any of the claims from 1 to 4, characterized in that the process of response to foreign substances carried out by the foreign substance response process section (59) comprises the step of inducing the light projection adjustment section (54) to carry out the light projection adjustment process again. 6. A yarn monitoring device (15) according to any one of claims 1 to 5, characterized in that it further comprises: a section for determining the presence / absence of a yarn (56) adapted to determine whether the yarn (10) is present or is not present in the detection region (36), in which the process of response to foreign substances carried out by the foreign substance response process section (59) comprises an operating process as if the yarn (10) were not present in the detection region (36) even when the presence determination section / absence of the yarn (56) determines that the yarn is present in the detection region (36). 7. A yarn monitoring device (15) according to any of the claims from 1 to 5, characterized in that the process of response to foreign substances carried out by the foreign substance response process section (59) comprises an emission process of a signal to detect foreign substances. 8. A yarn monitoring device (15) according to any of the claims from 1 to 7, characterized in that it further comprises a notification device (46, 47) in which the notification device (46, 47) is adapted to creating a notification when the detection value is outside the range of determination of foreign substances continuously for the time of determination of foreign substances in the state in which the yarn (10) is not present in the detection region (36) . 9. A yarn monitoring device (15) according to any one of claims 1 to 8, characterized in that: the process section of response to foreign substances (59) determines that the foreign substances enter the detection region (36) when a state in which the detection value is outside the range of determination of foreign substances above a limit value in one side of the determination range of the foreign substances it continues for a predetermined time in the state in which the yarn (10) is not present in the detection region (36), and determines that the foreign substances have left the detection region (36) when a state in which the detection value is outside the range of determination of the foreign substances beyond a limit value on the other side of the determination range of the substances extraneous continues for a predetermined time in a state in which the yarn (10) is not present in the detection region (36). 10. A yarn monitoring device (15) according to claim 8, characterized in that: the range of determination of foreign substances is defined relatively with a reference value, which is a past detection value, as a reference, and when the reference value is greater than or equal to a lower limit value and less than or equal to an upper limit value of the determination range of foreign substances, the foreign substance response process section (59) uses a new determination interval of foreign substances defined with the detection value as a reference value in the subsequent determination. 11. A yarn monitoring device (15) according to claim 9, characterized in that the range of determination of the foreign substances is defined in a fixed manner. 12. A yarn monitoring device (15) according to any one of claims 1 to 11, characterized in that it further comprises: a section for determining the presence / absence of a yarn (56) adapted to determine whether the yarn (10) is present or is not present in the detection region (36), in which the section for determining the presence / absence of the yarn (56) determines that the yarn (10) is present in the detection region (36) when the detection value is greater than or equal to a threshold value for determining the presence / absence of the yarn, e the threshold value for determining the presence / absence of the yarn is set to a value outside the range of determination of foreign substances. 13. A yarn winding machine characterized in that it comprises: the yarn monitoring device (15) according to any one of claims 1 to 12; is a winding section (18) able to wind a yarn (10) which passes through the monitoring device of a yarn (15) to form a cone (20). 14. Textile machine comprising a yarn monitoring device (15) according to any of the claims from 1 to 12, characterized in that: said textile machine comprises a winding section (18) adapted to wind the yarn (10) to form a cone (20), and the foreign substance response process performed by the foreign substance response process section (59) comprises a process of emitting a winding inhibit signal to prevent winding of the yarn (10) by the winding section (18). ). 15. Textile machine comprising a yarn monitoring device (15) according to any one of claims 1 to 12, characterized in that: said textile machine comprises a splicing device for a yarn (14) suitable for performing a yarn splicing operation, and the process of response to foreign substances carried out by the foreign substance response process section (59) comprises a process of emission of a yarn junction signal to induce the yarn junction device (14) to perform the junction operation. of the yarn. 16. Method for monitoring a yarn comprising the following phases: projecting light on a sensing region (36) through which a yarn (10) flows; receiving the light projected from a light projection section (41); is detecting a detection value corresponding to a light receiving quantity, characterized by: evaluating a state of the yarn (10) present in the detection region (36) based on the detection value, performing a light projection adjustment process to adjust an actuation control value of the light projection section (41) so that the detection value becomes a predetermined value in a state in which the yarn (10) is not present in the detection region (36), e carrying out a process of response to foreign substances when the detection value is outside a predetermined range of determination of foreign substances for a predetermined time of determination of foreign substances in the state in which the yarn (10) is not present in the detection region (36), e re-run the light projection adjustment process when a detection value is outside a normal range, which is an interval of a preset detection value such that it has a greater width than the width of the determination interval of foreign substances in the state in which the yarn (10) is not present in the detection region (36).