FIBER BUNDLE SUPPLY STOP APPARATUS FOR SPINNING MACHINE

Abstract

 In a fiber bundle supply stop apparatus for a ring spinning machine (11), a plurality of yarn break detectors (13) detects whether or not a yarn on a corresponding spindle (12) is broken, a position detector (15, 16, 24, 25) detects a position of a worker (W) or a machine providing yarn piecing service, and a controller (17, 21) controls fiber bundle supply stop devices (14) to estimate a time required for the worker (W) or the machine to arrive at a position of the spindle (12A, 12B) having a yarn break based on the detected position of the worker (W) or the machine, to continue supply of the fiber bundle to the spindle (12A, 12B) having the yarn break when the estimated required time is a predetermined value or smaller, and to stop supply of the fiber bundle when the estimated required time is greater than the predetermined value.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates to a fiber bundle supply stop apparatus for a spinning machine, and more particularly to a bundle supply stop apparatus for a spinning machine that includes a drafting device and is capable of stopping the supply of a fiber bundle to the drafting device of each of spindles of the spinning machine.

[0002] In a spinning machine having a plurality of spindles and spinning a roving or a sliver at each of the spindles, if a yarn break occurs at any of the spindles, spinning is continued on the spindles other than the spindle at which the yarn break has occurred. In some spinning machines, supply of a fiber bundle to the drafting device of a spindle having a yarn break is continued and the fiber bundle fed to such drafting device is sucked and collected. Some other spinning machines have an apparatus for controllably stopping the supply of fiber bundle to the drafting device of the troubled spindle.

[0003] In the former case in which the fiber bundle is supplied continuously in the spindle having the yarn break and the fiber bundle fed to the drafting device of the spindle is collected by suction, the fiber bundle remains to be supplied wastefully until yarn piecing operation is started. On the other hand, in the latter case in which the supply of fiber bundle to the spindle having the yarn break is stopped or suspended, such wasteful supply of fiber bundle is prevented. However, once the supply of fiber bundle is stopped in a spindle, it takes a several seconds to bring the spindle back to the state that allows a worker or a servicing machine of the spinning machine to start the yarn piecing operation and, therefore, it also takes a long time to complete the yarn piecing operation after the worker or the servicing machine has arrived at the spindle having the yarn break, which hinders efficient yarn piecing operation by the worker or the servicing machine, thus lowering the operating efficiency of the spinning machine.

[0004] Japanese Unexamined Patent Application Publication No. 3-40825 proposes a method according to which, when a yarn break is detected in a ring spinning machine, yarn piecing operation is performed once by the servicing machine at the spindle having the yarn break without immediately stopping the supply of roving to the drafting device of the spindle, and in the case of failure in yarn piecing operation, a roving stop device provided in the spindle is operated by the servicing machine thereby to stop the supply of roving to the drafting device.

[0005] In the method disclosed in the above Publication, however, if the servicing machine fails to piece the yarn, the supply of the roving to the spindle having the yarn break is continued until the yarn piecing operation by the servicing machine fails. Therefore, depending on the distance between the position of the servicing machine at the time of a yarn break and the spindle at which the yarn break has occurred, it may take a long time for the servicing machine to arrive at the target spindle. Thus, the roving is kept supplied wastefully to the drafting device of the spindle and the roving (the fiber bundle) may be wound around a draft roller.

[0006] The present invention has been made in view of the above problems and is directed to providing a fiber bundle supply stop apparatus for a spinning machine that, in case of a yarn break, prevents wasteful supply of the fiber bundle to a spindle which has the yarn break to thereby prevent lowering of the operating efficiency of the spinning machine.

SUMMARY OF THE INVENTION

[0007] In accordance with an aspect of the present invention, a fiber bundle supply stop apparatus for a spinning machine that solves the above problems includes a plurality of drafting devices and a plurality of spindles provided for the respective drafting devices. Each drafting device drafts a fiber bundle and the corresponding spindle is used to spin the fiber bundle into a yarn. The fiber bundle supply stop apparatus has a plurality of fiber bundle supply stop devices for the respective spindles. Each fiber bundle supply stop device is configured to stop supply of the corresponding fiber bundle to the corresponding drafting device. The fiber bundle supply stop apparatus includes a plurality of yarn break detectors, a position detector, and a controller. The yarn break detectors are provided for the respective spindles. Each yarn break detector detects whether or not the yarn on the corresponding spindle is broken. The position detector detects a position of a worker or a machine providing yarn piecing service. The controller controls the fiber bundle supply stop devices to estimate a time required for the worker or the machine to arrive at a position of one of the spindles having the yarn break based on the position of the worker or the machine detected by the position detector, to continue supply of the fiber bundle to the spindle having the yarn break when the estimated required time is a predetermined value or smaller, and to stop supply of the fiber bundle to the spindle having the yarn break when the estimated required time is greater than the predetermined value.

[0008] Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] 

FIG. 1A is schematic view showing a layout of spinning machines and position detectors according to a first embodiment of the present invention;

FIG. 1B is a schematic view showing a layout of spindles of the spinning machine, yarn break sensors, and a fiber bundle supply stop apparatus;

FIG. 2 is a schematic view showing a layout of the position detectors according to another embodiment; and

FIG. 3 is a schematic view showing a layout of position detectors according to still another embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

First Embodiment

[0010] A first embodiment of the present invention will now be described with reference to the attached drawings.

[0011] Referring to FIG. 1A, a plurality of ring spinning machines 11 as the spinning machine of the present invention is disposed side by side to each other. As shown in FIG. 1B, each ring spinning machine 11 includes a plurality of spindles 12 each having a yarn break sensor 13 as the yarn break detector of the present invention. The ring spinning machine 11 further includes for each of the spindles 12 a fiber bundle supply stop device 14 that is configured to stop the supply of a fiber bundle, or roving, to a drafting device (not shown) of the spindle 12. As the fiber bundle supply stop device 14, any device of a known type may be used.

[0012] As shown in FIG. 1A, each ring spinning machine 11 has at the opposite ends thereof optical sensors 15, 16 as the position detectors for detecting the position of a worker W. Each optical sensor 15 includes a pair of light-emitting portion 15A and a light-receiving portion 15B and each optical sensor 16 includes a pair of light-emitting portion 16A and a light-receiving portion 16B, respectively. As shown in FIG. 1A, a pair of the light-emitting portions 15A, 16A and a pair of the light-receiving portions 15B, 16B are mounted in any two adjacent ring spinning machines 11 on the sides thereof that face each other across an aisle between the two ring spinning machines 11 so that the light-emitting portions 15A and 16A in one of the two adjacent ring spinning machines 11 face the light-receiving portions 15B, 16B in the other of the two adjacent ring spinning machines 11, respectively, and also in such an arrangement that the light-emitting portion 15A and the light-receiving portion 15B of the first optical sensor 15 are located outward of the light-emitting portion 16A and the light-receiving portion 16B of the second optical sensor 16 with respect to the longitudinal direction of the machine frame of the ring spinning machine 11.

[0013] In FIG. 1A, numeral 30 designates two opposite walls of a textile spinning mill in which the ring spinning machines 11 are installed. Two ring spinning machines 11 that are installed on the opposite sides in the textile spinning mill as seen in the direction in which the ring spinning machines 11 are arranged side by side to each other are positioned adjacent to the walls 30, respectively, and the outer side of each such ring spinning machine 11 faces its adjacent wall 30. Each wall 30 has the light-emitting portions 15A, 16A provided at positions corresponding to the light-receiving portions 15B, 16B on the opposite ends of the adjacent ring spinning machine 11. That is, each of such ring spinning machines 11 that are adjacent to the wall 30 has on the side of the ring spinning machine 11 facing the wall 30 the light-receiving portions 15B, 16B at positions corresponding to the light-emitting portions 15A, 16A provided on the wall 30. Therefore, the position of the worker W present in an aisle between any two adjacent ring spinning machines 11 or in an aisle between the wall 30 and its adjacent ring spinning machine 11 is detectable.

[0014] Generally, a cleaning device, a so-called traveling cleaner (not shown) is provided in a textile spinning mill. The traveling cleaner travels in the textile spinning mill along the ring spinning machines 11. For the traveling cleaner not to be detected by the optical sensors 15, 16, the optical sensors 15, 16 are disposed near the floor level.

[0015] Each ring spinning machine 11 has at one end thereof a control device 17 having therein a CPU 18 and a memory 19 and connected to a host computer 21 via a local area network (LAN) 20. The host computer 21 has also therein a CPU 22 and a memory 23. The control devices 17 and the host computer 21 cooperate to form the controller of the present invention.

[0016] Each control device 17 is connected to the yarn break sensors 13 through signal lines (not shown) and identifies the spindle 12 at which a yarn break has occurred based on a detection signal from the yarn break sensors 13. The spindles 12 at which a yarn break has occurred are designated by 12A and 12B as the yarn-broken spindles and indicated by X in FIG. 1A. The control device 17 is connected to the fiber bundle supply stop devices 14 through signal lines (not shown) and outputs a fiber bundle supply stop command to the fiber bundle supply stop devices 14 of the yarn-broken spindles 12A, 12B that need have the supply of the fiber bundle stopped. If the worker W is positioned close to the yarn-broken spindle 12A when the yarn breaks are present at the yarn-broken spindles 12A, 12B and it is estimated by the control device 17 that the time required for the worker W to arrive at the yarn-broken spindle 12A is short, the control device 17 delays the time to stop the supply of the roving. Specifically, when the worker W is at a position in an aisle between two adjacent ring spinning machines 11 and if the yarn-broken spindle 12A is located on the side of one of the ring spinning machines 11 that faces the aisle in which the worker W is present, as shown in FIG. 1A, the control device 17 outputs a command signal to the fiber bundle supply stop device 14 for the yarn-broken spindle 12A with a delay of a predetermined length of time.

[0017] The control device 17 is connected to the light-receiving portions 15B, 16B of the optical sensors 15, 16 through signal lines (not shown). Based on detection signal from the light-receiving portions 15B, 16B, the control device 17 makes determination as to whether or not the worker W has entered the aisle between any two adjacent ring spinning machines 11 or the aisle between either one of the walls 30 and its adjacent ring spinning machine 11, or as to whether or not the worker W has exited from the aisle between any two adjacent ring spinning machines 11 or the aisle between either one of the walls 30 and its adjacent ring spinning machine 11. Specifically, when the control device 17 receives a detection signal from the light-receiving portion 15B disposed at an end of the ring spinning machine 11 and then a detection signal from the light-receiving portion 16B that is disposed inward of the light-receiving portion 15B, the control device 17 determines that the worker W has entered the aisle between the two adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11. In the case that the control device 17 receives detection signal from the light-receiving portion 15B after receiving the detection signal from the light-receiving portion 16B, on the other hand, the control device 17 determines that the worker W has exited from the aisle between the adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11.

[0018] In the first embodiment, the light-emitting portions 15A, 16A are provided on one side (lower side in FIG. 1A) of the ring spinning machines 11 and the light-receiving portions 15B, 16B are provided on the other side (upper side in FIG. 1), except the ring spinning machine 11 that is disposed at the bottom as seen in FIG. 1A and have on both sides thereof the light-receiving portions 15B, 16B. Therefore, determination as to whether the worker W has entered the aisle between any two adjacent ring spinning machines 11 or the worker W has exited from the aisle is possible regarding only one side of the machine frame of the ring spinning machine 11 (upper side in FIG. 1). Thus, the detection signal from the light-receiving portions 15B, 16B of the ring spinning machine 11 to which the control device 17 is provided is not sufficient for the control device 17 to make determination as to whether the worker W has entered the aisle between the ring spinning machine 11 and the ring spinning machine 11 that is next to or below the ring spinning machine 11 as viewed in FIG. 1 or as to whether the worker W has exited from the aisle between the adjacent ring spinning machines 11.

[0019] In order to solve the above problem, each control device 17 outputs to the host computer 21 a query asking whether the worker W has entered the aisle between the ring spinning machine 11 for which the control device 17 is provided and its adjacent ring spinning machine 11 or the worker W has exited from the aisle. The host computer 21 storing in its memory 23 data on the entry and the exit of the worker W into and out of the aisle between the adjacent ring spinning machines 11 transmits such information to the control device 17 of the corresponding ring spinning machine 11.

[0020] The operation of the ring spinning machines 11 configured as explained above will be described.

[0021] During the operation of the ring spinning machines 11, if a yarn break has occurred at any of the spindles 12, the control device 17 determines the presence of the yarn break in response to a detection signal from the yarn break sensor 13 for the spindle 12. The information on the position of the spindle 12 at the yarn break has occurred, i.e. the information on the yarn-broken spindle 12A, is stored in the memory 19 of the control device 17.

[0022] According to the presence of or absence of a detection signal from the light-receiving portions 15B, 16B of the optical sensors 15, 16, the control device 17 makes a determination as to whether or not the worker W has entered the aisle between the adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11. Specifically, upon receiving a detection signal from the light-receiving portion 15B disposed at an end of the ring spinning machine 11 and subsequently a detection signal from the light-receiving portion 16B disposed inward of the light-receiving portion 15B, the control device 17 determines that the worker W has entered the aisle between the adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11. In the case that the control device 17 receives a detection signal from the light-receiving portion 15B after receiving a detection signal from the light-receiving portion 16B, on the other hand, the control device 17 determines that the worker W has exited from the aisle between the adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11.

[0023] As shown in FIG. 1A, the walls 30 have thereon the light-emitting portions 15A, 16A of the optical sensors 15, 16, and the ring spinning machines 11 facing the walls 30 have on the side thereof that is adjacent to the respective walls 30 include the light-receiving portions 15B, 16B in facing relation to their corresponding light-emitting portions 15A, 16A on the walls 30. Therefore, the determination as to whether the worker W is present in the aisle between the wall 30 and its adjacent ring spinning machine 11 is made based on the detection signal from the light-receiving portions 15B, 16B provided on the side of the ring spinning machine 11 facing the wall 30.

[0024] The control device 17 estimates the time required for the worker W to arrive at the yarn-broken spindle 12A based on the current position of the worker W detected by the optical sensors 15, 16. The control device 17 causes the fiber bundle supply stop device 14 to allow the supply of fiber bundle to the yarn-broken spindle 12A when the estimated required time is a predetermined value or smaller, and to stop the supply of fiber bundle to the yarn-broken spindle 12A when the estimated required time is greater than the predetermined value.

[0025] The control device 17 calculates the position of the worker W based on the detection signal from the position detector (the optical sensors 15, 16). When a yarn break occurs, the control device 17 locates the position of the yarn-broken spindle 12A based on the detection signal from the yarn break detector (the yarn break sensor 13), determines whether or not the estimated time required for the worker W to arrive at the yarn-broken spindle 12A is greater than the predetermined value, and stops the supply of fiber bundle to the yarn-broken spindle 12A if the estimated time is greater than the predetermined value.

[0026] When a yarn break detection signal from the yarn break sensor 13 for the yarn-broken spindle 12A is received by the control device 17 and if the worker W exits from the aisle between the adjacent ring spinning machines 11, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12A. In response to this, the fiber bundle supply stop device 14 is operated to stop the supply of fiber bundle (or the sliver) to the yarn-broken spindle 12A. When the worker W is out of the aisle between the adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11, the time required for the worker W to arrive at the yarn-broken spindle 12A is greater than the predetermined value. Then, the control device 17 outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12A.

[0027] When a yarn break detection signal from the yarn break sensor 13 for the yarn-broken spindle 12A is received by the control device 17 and if the worker W enters the aisle between the ring spinning machines 11 for the yarn-broken spindle 12A, or the aisle between the wall 30 and its adjacent ring spinning machine 11, the supply of fiber bundle to the yarn-broken spindle 12A is continued, and after a predetermined period of time has elapsed, the control device 17 outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12A. If yarn piecing operation is completed before the lapse of the predetermined period of time, the control device 17 outputs no fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12A. The above predetermined period of time is set appropriately in accordance with the speed of the ring spinning machine 11 or the thickness (the count) of the fiber to be spun. For example, in the case of a yarn break in spinning of a fine yarn and that the roving is kept supplied, it takes a longer time for the yarn to be wound around the draft roller and, therefore, the predetermined period of time may be set relatively long. However, the supply of roving is stopped or suspended at most in several tens of seconds after the detection of a yarn break. As is apparent from the foregoing description, the predetermined period of time refers to a delay time, or a length of time to elapse before the control device 17 outputs a fiber bundle supply stop command to a fiber bundle supply stop device 14 of a yarn-broken spindle 12.

[0028] For example, when the worker W is present in the aisle between the two adjacent ring spinning machines 11 and the yarn-broken spindle 12A is located on one side of the two adjacent ring spinning machines 11 that faces the aisle, a moving distance D1 which the worker W need move to reach the yarn-broken spindle 12A is short. The control device 17, which has received the detection signal from the yarn break sensor 13 of the yarn-broken spindle 12A, determines that the time required for the worker W to arrive at the yarn-broken spindle 12A is a predetermined value or smaller. Accordingly, the supply of fiber bundle to the yarn-broken spindle 12A is continued. The supply of fiber bundle to the yarn-broken spindle 12A is still continued when the worker W arrives at the yarn-broken spindle 12A for yarn piecing, so that the worker W can start the yarn piecing operation without removing the yarn wounded around the draft roller or manually releasing the stoppage of the fiber bundle supply stop device 14 before starting the yarn piecing operation.

[0029] When the worker W is present in the aisle between the two adjacent ring spinning machines 11 and the yarn-broken spindle 12B is located on one side of the ring spinning machine 11 that is adjacent to the wall 30, as shown in FIG. 1A, the moving distance which the worker W moves to reach the yarn-broken spindle 12B is long as indicated by an arrow D2. The control device 17, which has received the detection signal from the yarn break sensor 13 of the spindle 12B, determines that the time required for the worker W to arrive at the yarn-broken spindle 12B is greater than the above predetermined value. Accordingly, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12B.

[0030] If the fiber bundle supply stop device 14 is not operated to stop the supply of fiber bundle before the worker W arrives at the yarn-broken spindle 12B, the worker W can start the yarn piecing operation immediately, which can improve the efficiency of yarn piecing operation by shortening the time required for resuming the spinning operation after the yarn break. Furthermore, if the yarn piecing operation by the worker W is not started after a lapse of a predetermined period of time, the control device 17 outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle 12B. A yarn break may occur at a new spindle while the worker W is moving toward the yarn-broken spindle 12A and the worker W may perform piecing operation at the new yarn-broken spindle 12A. In such a case, the time required for the worker W to arrive at the yarn-broken spindle 12A may be greater than the predetermined period of time.

[0031] In the case that the fiber bundle supply stop device 14 has been operated and the supply of fiber bundle (or the sliver) to the yarn-broken spindle is stopped or suspended before the worker W arrives at the yarn-broken spindle, the worker W manually removes the yarn wound around the draft roller and manually resets the stoppage of the fiber bundle supply stop device 14 before starting the yarn piecing operation.

[0032] The above-described first embodiment offers the following effects.

(1) The fiber bundle supply stop apparatus includes a plurality of fiber bundle supply stop devices provided for each of spindles of the ring spinning machine 11 and configured to stop the supply of fiber bundle (roving) to the drafting device of the spindles 12. The fiber bundle supply stop apparatus further includes the yarn break sensor 13 (the yarn break detector) provided for each of the spindles 12, the position detectors (the optical sensors 15, 16) that detect the position of the worker W of yarn piecing, and the control device 17 (the controller) that estimates the time required for the worker W to arrive at the position of the spindle having a yarn break based on the current position of the worker W who provides yarn piecing service detected by the position detectors and controls and causes the fiber bundle supply stop device 14 to continue the supply of fiber bundle to the yarn-broken spindle 12A when the estimated required time is a predetermined value or smaller, or to stop the supply of fiber bundle to the yarn-broken spindle 12A when the estimated time is greater than the predetermined value.
According to the configuration of the first embodiment, the control device 17 locates the position of the worker W based on the detection signal from the position detectors. If a yarn break occurs, the control device 17 locates the yarn-broken spindles 12A, 12B based on the detection signal from the yarn break sensor 13 and estimates the time required for the worker W to arrive at the yarn-broken spindles 12A, 12B based on the current position of the worker W who performs yarn piecing operation detected by the position detectors. The control device 17 makes a determination as to whether or not the estimated time is a predetermined value or smaller. When the estimated required time is the predetermined value or smaller, the supply of fiber bundle to the yarn-broken spindle is continued. Therefore, when the required time for the worker W to arrive at the yarn-broken spindle is short, supply of fiber bundle is continued until yarn piecing operation by the worker W is started, which helps to improve the efficiency in yarn piecing operation. When the estimated time is long, on the other hand, supply of fiber bundle is stopped, so that winding of the fiber bundle on the draft roller to such an extent that causes a problem to yarn piecing operation is prevented. Therefore, wasteful supply of fiber bundle to a spindle having a yarn break is prevented at the occurrence of the yarn break, helping to improve the efficiency in yarn piecing operation.

(2) If the control device 17 receives a yarn break detection signal from the yarn break sensor 13 and the worker W has exited from the aisle between any two adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the spindle at which the yarn break has occurred. Specifically, if the worker W has exited from the aisle, the control device 17 determines that the time required for the worker W to arrive at the yarn-broken spindle 12A is greater than the predetermined period of time, so that it is unnecessary for the control device 17 to calculate the time required for the worker W to arrive at the yarn-broken spindle.

(3) If the control device 17 receives a yarn break detection signal from the yarn break sensor 13 and the worker W is present in the aisle between any two adjacent ring spinning machines 11 or the aisle between the wall 30 and its adjacent ring spinning machine 11, the control device 17 outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the spindle having the yarn break after a predetermined period of time has elapsed. If the yarn piecing operation is completed before the lapse of the predetermined period of time, the control device 17 outputs no fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle. Accordingly, output of a fiber bundle supply stop command to the fiber bundle supply stop device 14 after the completion of the yarn piecing operation is prevented. Furthermore, in the case that the time required for the worker to move arrive at the spindle having a yarn break is estimated to be the predetermined value or smaller and the supply of the fiber bundle is continued, a fiber bundle supply stop command is output to the fiber bundle supply stop device 14 after the lapse of the predetermined period of time, so that the supply of the fiber bundle is suspended and, therefore, wasteful supply of the fiber bundle is prevented.

(4) The position detectors correspond to the optical sensors 15, 16. As the position detectors, an IC tag, for example, may be used. However, the use of the optical sensors will release the worker W from carrying a special device with him/her for such position detection.

Second Embodiment

[0033] A second embodiment of the present invention will now be described with reference to drawings. In the second embodiment, the control device 17 estimates the time required for the worker W to arrive at the yarn-broken spindle 12A based on the moving distance between the worker W and the yarn-broken spindle 12A, the number of the yarn-broken spindles 12A, and the moving speed of the worker W.

[0034] Even when the moving distances between the current position of the worker W and the respective yarn-broken spindles 12A are the same, the time required for the worker W to arrive at such yarn-broken spindles 12A calling for yarn piecing operation varies depending on the number of the yarn-broken spindles 12A and the moving speed of the worker W.

[0035] According to the second embodiment, however, the time required for the worker W to arrive at the yarn-broken spindle 12A is estimated more accurately by using the moving distance between the worker W and the respective yarn-broken spindles 12A, the number of such yarn-broken spindles 12A, and the moving speed of the worker W.

[0036] The present invention is not limited to the above-described embodiments, but it may be embodied in various ways as follows.

[0037] As shown in FIG. 2, the aisle between any two adjacent ring spinning machines 11 and, although not shown in the drawing, the aisle between the wall 30 and its adjacent ring spinning machine 11 are divided into a plurality of areas (or blocks) in the longitudinal direction of the machine frame of the ring spinning machine 11, respectively, and pairs of optical sensors 15, 16 are provided at the boundary between any two adjacent areas, in addition to the optical sensors 15, 16 provided at the opposite ends of the ring spinning machine 11. Specifically, a pair of the light-emitting portions 15A, 16A and a pair of the light-receiving portions 15B, 16B are mounted in any two adjacent ring spinning machines 11 on the sides thereof that face each other across an aisle between the two ring spinning machines 11 so that the light-emitting portions 15A, 16A in one of the adjacent two ring spinning machines 11 face the light-receiving portions 15B, 16B in the other of the two adjacent ring spinning machines 11, respectively. When the yarn break sensor 13 of a spindle 12 in the area where the worker W is not present detects a yarn break, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the above spindle, and, on the other hand, when the yarn break sensor 13 of a spindle 12 in the area where the worker W is present detects a yarn break, the control device 17 may output a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the yarn-broken spindle after a lapse of a predetermined period of time.

[0038] In the arrangement of FIG. 2, when a yarn break is detected by the yarn break sensor 13 of a spindle 12 in the area that is rearward of the area in which the worker W is then present with respect to the traveling direction of the worker W, taking the traveling direction (or the moving direction) of the worker W into consideration, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the above spindle 12 having the yarn break, and, on the other hand, when a yarn break is detected by the yarn break sensor 13 of a spindle 12 in the area on the frontward of the area in which the worker W is then present with respect to the traveling direction of the worker W, the control device 17 immediately outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14 of the spindle having the yarn break after a lapse of a predetermined period of time.

[0039] Each control device 17 may be configured to receive the positional information of the worker W from the control device 17 of the ring spinning machine 11 that is adjacent to the side of the ring spinning machine 11 having the receiving-side control device 17 on which the light-emitting portions 15A, 16A are provided. In other words, each control device 17 may receive the information as to whether the worker W is present in the aisle between the ring spinning machine 11 having the receiving-side control device 17 and the ring spinning machine 11 that is adjacent to the side of the ring spinning machine 11 having the receiving-side control device 17 on which the light-emitting portions 15A, 16A are provided through communication with the control device 17 of the above adjacent ring spinning machine 11.

[0040] The position detectors that detect the position of the worker W may employ a motion sensor (a human sensor) that selectively detects the worker W (or a person), instead of the optical sensors 15, 16 including the light-emitting portions 15A, 16A and the light-receiving optical sensors 15B, 16B. Examples of the motion sensor include an infrared sensor and an electrostatic capacitance sensor. With the use of the motion sensor installed at a position that is not close to the floor level, the traveling cleaner will not be detected erroneously as the worker W even though the installation position of the sensor is not close to the floor level. Furthermore, the motion sensor does not require the pair of the light-emitting portion and the light-receiving portion. The motion sensor detects the worker W irrespective of the arrangement in which the ring spinning machines 11 are disposed side by side to each other.

[0041] As shown in FIG. 3, as the position detectors, two pairs of first and second infrared sensors 24, 25 as the position detectors may be disposed in any two adjacent ring spinning machines 11 on the sides thereof that face each other across the aisle between such two adjacent ring spinning machines 11. In the side-by-side arrangement of the ring spinning machines 11, as shown in FIG. 3, in which the outermost ring spinning machines 11 located on the opposite sides of such side-by-side arrangement have on one side thereof no facing ring spinning machine 11, the moving direction of the worker W moving along the outer side of the outermost ring spinning machine 11 can be determined successfully by the control device 17 based on the detection signal from the infrared sensors 24, 25. In other words, the control device 17 can make the determination as to whether or not the worker W is present at a spindle 12 of the ring spinning machine 11 to which the control device 17 is provided, based on detection signal from the infrared sensors 24, 25. Therefore, the control device 17 need not have positional information on the worker W through the host computer 21 or the control devices 17 of the adjacent ring spinning machines 11. Similar effects may be obtained by using other motion sensors than the infrared sensors 24, 25.

[0042] A pair of an IC tag and an IC tag reader or a pair of an IC card and an IC card reader may be used as the position detectors. In other words, the worker W may carry an IC tag or a non-contact IC card, and an IC tag reader or an IC card reader may be provided in the ring spinning machine 11. In such cases, the servicing device will not be detected erroneously as the worker W and furthermore distinction of one worker W who is in charge of yarn piecing operation from another worker W who is in charge of any other task can be made properly through the IC tag or the IC card. By using an IC tag reader or an IC card reader on the side of a ring spinning machine 11 that has no adjacent ring spinning machine 11 to face, the worker W moving along such side of the ring spinning machine 11 can be detected. Therefore, the control device 17 need not obtain positional information on the worker W through the host computer 21 or the control device 17 of the adjacent ring spinning machines 11.

[0043] It may be so configured that the control device 17 estimates the time required for the worker W to arrive at the spindle having a yarn break based on the position of the spindle detected by the yarn break sensor 13 and the current position of the worker W detected by the position detectors and, when the estimated time is greater than a predetermined value, the control device 17 outputs a fiber bundle supply stop command to the fiber bundle supply stop device 14.

[0044] The control device 17 may also be configured to identify the type of a task to be taken by the worker W and reflect the identified type of the task when estimating the required time. In a textile spinning mill, there is a maintenance personnel, as well as the worker assigned to yarn piecing operation. Therefore, with this configuration, the estimated time required for the worker who performs yarn piecing operation to arrive at the spindle having the yarn break is more appropriate and undesired issuance of a fiber bundle supply stop command by the control device 17 is prevented when the worker is near the spindle having the yarn break.

[0045] The control device 17 may be configured such that when a plurality of spindles each having a yarn break is present on one side of a machine frame of the ring spinning machine 11, the control device 17 immediately outputs a fiber bundle supply stop command to at least the fiber bundle supply stop device 14 of the spindle 12 that is most distant from the worker W.

[0046] According to the present invention, the fiber bundle is not limited to a roving, but may be a sliver. For example, the fiber bundle supply stop device may be used in a ring spinning machine that spins a yarn from a sliver by using a drafting device that drafts a fiber at a larger draft ratio than an ordinary three-line drafting device.

[0047] According to the present invention, the spinning machine is not limited to a ring spinning machine, but may be a friction spinning machine or a spinning machine for spinning a fascinated yarn.

[0048] The yarn piecing operation may be performed by a servicing machine. In this case, the position of the servicing machine is detected by the position detectors and the time required for the servicing machine to arrive at the spindle having a yarn break is estimated based on the position of the servicing machine detected by the position detectors.

[0049] In a fiber bundle supply stop apparatus for a ring spinning machine (11), a plurality of yarn break detectors (13) detects whether or not a yarn on a corresponding spindle (12) is broken, a position detector (15, 16, 24, 25) detects a position of a worker (W) or a machine providing yarn piecing service, and a controller (17, 21) controls fiber bundle supply stop devices (14) to estimate a time required for the worker (W) or the machine to arrive at a position of the spindle (12A, 12B) having a yarn break based on the detected position of the worker (W) or the machine, to continue supply of the fiber bundle to the spindle (12A, 12B) having the yarn break when the estimated required time is a predetermined value or smaller, and to stop supply of the fiber bundle when the estimated required time is greater than the predetermined value.

Claims

1. A fiber bundle supply stop apparatus for a spinning machine (11), the spinning machine (11) including a plurality of drafting devices and a plurality of spindles (12) provided for the respective drafting devices, each drafting device drafting a fiber bundle and the corresponding spindle (12) being used to spin the fiber bundle into a yarn, the fiber bundle supply stop apparatus having a plurality of fiber bundle supply stop devices (14) for the respective spindles (12), each fiber bundle supply stop device (14) being configured to stop supply of the corresponding fiber bundle to the corresponding drafting device, the apparatus characterized by comprising:

a plurality of yarn break detectors (13) provided for the respective spindles (12), each yarn break detector (13) detecting whether or not the yarn on the corresponding spindle (12) is broken;

a position detector (15, 16, 24, 25) that detects a position of a worker (W) or a machine providing yarn piecing service; and

a controller (17, 21) that controls the fiber bundle supply stop devices (14) to estimate a time required for the worker (W) or the machine to arrive at a position of one of the spindles (12A, 12B) having the yarn break based on the position of the worker (W) or the machine detected by the position detector (15, 16, 24, 25), to continue supply of the fiber bundle to the spindle (12A, 12B) having the yarn break when the estimated required time is a predetermined value or smaller, and to stop supply of the fiber bundle to the spindle (12A, 12B) having the yarn break when the estimated required time is greater than the predetermined value.

2. The fiber bundle supply stop apparatus according to claim 1, characterized in that the controller (17, 21) estimates the required time based on a moving distance for the worker (W) or the machine to arrive at the position of the spindle (12A, 12B) having the yarn break, the number of the yarn breaks, and a moving speed of the worker (W) or the machine.

3. The fiber bundle supply stop apparatus according to claim 1 or 2, characterized in that the position detector (15, 16, 24, 25) is an optical sensor (15, 16).

4. The fiber bundle supply stop apparatus according to claim 2, characterized in that the controller (17, 21) identifies type of a task to be taken by the worker (W) and, when estimating the required time, reflects the identified type of the task.

5. The fiber bundle supply stop apparatus according to claim 1, characterized in that the controller (17, 21) estimates the time required for the worker (W) or the machine to arrive at the spindle (12A, 12B) having the yarn break based on a position of the spindle (12A, 12B) having the yarn break detected by the yarn break detector (13) and the position of the worker (W) or the machine detected by the position detector (15, 16, 24, 25), and, when the estimated time is greater than a predetermined value, outputs a fiber bundle supply stop command to the fiber bundle supply stop device (14) corresponding to the spindle (12A, 12B) having the yarn break.

Drawing