JPH11152630A - Yarn cutting in fine spinning frame - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for easily cutting a yarn in the doffing step of a fine spinning frame. SOLUTION: This method comprises steps of judging the timing A of forming a fine yarn by detecting a spinning length, first generated after a full bobbin, from the valley section of a heart cam; setting a draft ratio of the draft part into a fine yarn forming draft ratio, lowering a ring rail when the next valley section of the heart cam comes up (timing B), returning the draft ratio in a reference draft when the spinning length, after the beginning of a fine yarn forming draft, comes up to the necessary length for a barrel winding and hip winding (timing C), applying the barrel winding formed into a fine yarn section to an outer periphery of a bobbin and applying the hip winding formed into the fine yarn section to a yarn holding section of a spindle base portion so that the fine yarn section bestrides a cutter of the spindle base portion.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a yarn cutting method for a spinning machine, and more particularly, to a yarn cutting method for a spinning machine having a yarn cutter at a spindle base and a yarn holding portion such as a knurl or a thread hook. Related to cutting method.

[0002]

2. Description of the Related Art Conventionally, in a spinning machine having a spindle as described above, when the amount of yarn to be doffed (generally full) is reached, the ring rail is raised to the top bunch winding position and the top bunch is placed on the top of the bobbin. Forming a winding, and then lowering the ring rail to a tail winding position corresponding to the yarn holding portion provided below the yarn cutter of the spindle,
A bobbin is formed around the bobbin, and a predetermined number of tail yarns are wound around the yarn holding portion.After that, the spindle is stopped, and the bobbin upper part is gripped by the bobbin gripper of the simultaneous doffing device together with the top bunch winding. The yarn connected to the yarn holding portion from the bobbin is cut by the yarn cutter.Then, the empty bobbin is mounted on the spindle, the spindle is restarted, and a new yarn is wound around the empty bobbin. (For example, Japanese Patent Publication No. 6-27382).

[0003]

In the above-mentioned method, the top bunch winding is grasped by a bobbin gripper so that the top bunch winding is not loosened when the bobbin is pulled out.
It is intended to cut even relatively thick, hard-to-cut yarns by pressing it firmly against the yarn cutter, but the cutter is cut off using the bobbin pulling-up operation with the thick, hard-to-cut yarn. However, there is a possibility that a large power is required for removing the bobbin, and the cutting may not be reliable. An object of the present application is to provide a yarn cutting method capable of reducing the power required for cutting when performing yarn cutting using bobbin pulling-up and reliably cutting.

[0004]

In order to solve the above problems,
In the present application, when the bobbin reaches the winding amount to be doffed, the ring rail is lowered to the bottom winding position, the bobbin is wound, the yarn is held in the yarn holding portion of the spindle base, the spindle is stopped, and then the bobbin is moved to the spindle. In a yarn cutting method in a spinning machine that cuts a yarn connected between a yarn holding portion and a bobbin with a cutter above the yarn holding portion, a draft part can be changed in draft ratio during spinning. The draft ratio of the draft part is changed at a timing near the end of spinning to form a fine thread portion, and when the spindle is stopped, the fine thread portion is located at a position corresponding to the cutter. (Claim 1). According to this configuration, even with a thick yarn that is difficult to cut, the thin yarn portion with reduced yarn strength is cut by the cutter by pulling out the bobbin, so that it is easily cut, and the power required for cutting can be greatly reduced. .

It is preferable that the draft ratio of the draft part is changed to the fine yarn forming draft ratio so that the yarn portion forming the body winding and the tail winding becomes the fine yarn portion (at such timing). . Specifically, the spinning length is detected based on the rotation of the heart cam, and the spinning length from the valley of the heart cam arriving after the spinning amount to be doffed becomes the next valley portion. During the rotation, when the spun yarn path length from the draft roller to the bobbin is left, the draft ratio of the draft part is changed from the standard draft ratio to the fine yarn forming draft ratio. When the spinning length was spun, the draft ratio was returned to the standard draft ratio (claim 3). According to the second and third aspects of the present invention, the tail yarn is removed from the yarn holding portion of the spindle after the pipe is changed, and the body winding portion is a portion which is removed by the winder in the subsequent stroke of the spinning machine. There is no mixing of the fine yarn portion into the yarn portion, and the yarn quality does not deteriorate.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a ring spinning machine according to the present invention. In FIG. 1, reference numeral 1 denotes a spindle of a spinning machine, which is connected to a main motor 2 controlled by a well-known inverter device 8 via a spindle drive system A including a chin pulley shaft 3 and the like. The draft part 4 includes a front roller 5, a middle roller 6, and a back roller 7. The front roller 5 is connected to the main motor 2 via a drive system B, and the middle roller 6 and the back roller 7 are connected to a main motor 2 and another control motor 24. In response to the rotation speed signal from the encoder 46 that detects the rotation speed of the front roller 5, the rotation speed of the second and back rollers 6 and 7 is controlled,
The draft ratio in the draft part 4 is set to the reference or fine yarn forming draft ratio set in the control device 50. With this configuration, the draft part 4 can freely change the draft ratio during spinning.

[0007] The ring rail 10 is a lifting pillar 1
1, the lower end of the lifting pillar 11 is connected to one end of the lifting tape 12. The other end of the lifting tape 12 is connected to a lifting roller 14 integrally attached to a ring rail elevating shaft 13. Another roller 15 is attached to the ring rail elevating shaft 13.
The other end of a lifting tape 16 having one end fixed to the roller 15 is fixed to a lifting drum 19 via a guide roller 18 which is rotatable in the middle of a lifting lever 17.

The base end of the lifting lever 17 is
It is swingably supported around the rotation shaft 20. The tip of the lifting lever 17 is pressed against the heart cam 21.
The heart cam 21 is rotated by a drive system B of the front roller 5 via a pulley 22, a chain 23, and a gear pair 25, so that a chase is provided to the ring rail 10. An encoder that outputs a predetermined number of pulses (here, 160 pulses) with one rotation of the heart cam 21
A damper 30 is connected to the heart cam shaft. Encoder 30
Are counted using the valley of the heart cam 21 as the starting point of the pulse count in the controller 50. When the next valley is reached (that is, at one chase), the pulse count value is reset and counted again. You. Pulley 22
A heart cam clutch 31 is interposed between the gear pair 25 and the gear pair 25. The clutch 31 is disconnected when the clutch 31 makes one rotation from a valley portion of the heart cam 21 which first arrives after the tube is full.

When a shaper feed clutch 42 to be described later is disengaged from the pulley 22 to the lifting drum 19 via an appropriate drive system 26, that is, the ring rail descends to the front roller 5 when the ring rail is fully loaded. The clutch 41, which is connected only when it is connected, is connected. The clutch 41 further rotates the shaft 29 via an appropriate drive system 27. The rotation of the shaft 29 is performed via the gear pair 28 by the rotation shaft 20.
Is to be conveyed to. The rotation of the shaft 29 is detected by the encoder 45 and input to the control device 50. The rotation of the shaft 29 is integrated by the control device 50,
It is the sum of the shaper feed amounts, that is, height position information of the ring rail 10. Therefore, the encoder 45 constitutes a position detecting means of the ring rail 10. A shaper-feeding clutch 42 is connected to the opposite side of the drive system 27 from the clutch 41. This clutch 42
A shaper feed is applied to the ring rail 10 during winding, and the ring rail 10 is connected to a ring rail raising motor 43 for raising the ring rail 10 to the winding start position SS after the tail winding is completed.

As shown in FIG. 3, the spindle 1 is provided at its base with a thread cutting cutter 62 having a large number of blades at a predetermined pitch in the circumferential direction. Cutter 62
On the lower side, a yarn holding portion 63 such as a knurl or a yarn hook is formed to hold the yarn in a wound state. The yarn holding portion 63 is not limited to the above, and may be of another form, for example, a mechanism for elastically holding the yarn vertically and positively.

Next, the control device 50 will be described. The control device 50 includes a central processing unit (CPU) 52, a ROM,
It is mainly composed of a storage means 51 composed of a RAM, and includes a full length, a spinning length required for the tail winding, a standard draft ratio, and a fine thread forming draft for spinning a fine thread portion smaller than the standard draft ratio. A keyboard 5 as input means for inputting a ratio, data required for a bobbin winding calculation, a number of fine yarn forming timing pulses for determining from which time a fine yarn is to be formed, and the like.
3 is provided. In addition, body winding length is body winding length = body winding coefficient *
(All lifts LL-Ring rail chase H when full)
Is obtained in the CPU by the following equation, and the body winding coefficient is (LL−
H) is a constant determined by how much the front roller 5 rotates while the ring rail is automatically lowered, and the rotation of the drive system from the front roller 5 to the lifting roller 14 via the clutch 41 and the lifting drum 19 It is determined by a numerical ratio. The tail winding length is determined in advance by the number of windings of the yarn around the yarn holding portion. In addition, Heart Cam 21
And the front roller 5 are connected by a mechanical drive system, so that the spinning length spun by one rotation of the heart cam 21 is known. The number of output pulses by the encoder 30 corresponding to the rotation amount of the heart cam 21 required to spin the yarn path length L to the yarn winding portion (see FIG. 3B) corresponds to one rotation of the heart cam 21. The number of pulses may be subtracted from the number of pulses from the encoder 30 (160 pulses).

The control device 50 stores an operation program from start to stop, which will be described later. In the flowchart of FIG. 2, step 1 is a winding command means at a reference draft ratio, and step 2 is a front roller 5.
Means for judging whether the full length has reached a preset full length based on data from a pulsar 46 (rotation detector: spinning length detecting device) connected to the controller. Step 3 is to stop the rotation of the main motor (machine stand). Step 4 is a means for determining whether or not the pulse count from the encoder 30 reset by detecting the valley of the heart cam 21 after the tube is full has reached the number of fine thread forming timing pulses. Step 5 is a draft ratio change instructing means for controlling the rotation of the middle roller and the back rollers 6 and 7 with respect to the rotation of the front roller 5 so that the draft has the fine yarn forming draft ratio. A means for judging from the pulse of the encoder 30 whether or not the valley has been rotated, that is, whether or not the bottom of the chase has been reached. Parts 63 and so is lowered to butt winding position where the height facing shaper feed clutch 4
2 is a ring rail descending command means for disconnecting the clutch 41 and connecting the clutch 41 and disconnecting the heart cam clutch 31 instead. In step 8, it is determined from the spinning amount data from the pulsar 46 that the spinning length from the start of the fine yarn forming draft in step 5 is the spinning length required for the tail winding and the trunk winding.
This is a means for returning to the reference draft ratio. Step 9 is a means for discriminating that the ring rail has reached the tail winding position by a detection signal from the encoder 45 and disconnecting the clutch 41. Step 10 is a step of determining a predetermined desired tail winding length after reaching the tail winding position. Whether the spinning corresponding to
Step 11 connects the shaper feed clutch 42 when the tail winding is completed, raises the ring rail 10 to the winding start position SS by the ring rail raising motor 43, and applies a brake to the spindle 1. And a stop command means for stopping the operation.

The clutch 41 is disengaged and the clutches 31, 42
Is started in the connected state, the machine is operated according to the operation program, and in step 1, the ring rail 10
Winds the yarn spun from the front roller 5 around the bobbin while repeating the shaper feed by the ring rail raising motor 43 and the chase by the heart cam 21, and rises toward the full tube to form the full bobbin F. Step 1
Then, the control motor 24 controls the rotation of the middle roller and the back rollers 6, 7 with respect to the front roller 5 so that the reference draft ratio previously input to the control device 50 is obtained. If it is determined in step 2 that the full pipe length has been reached based on a signal from the spinning length detecting means 46, in step 3, the main motor 2 is decelerated in accordance with a predetermined deceleration gradient by the inverter 8. The rotation of the heart cam 21 is continued, and if it is determined in step 4 that the valley of the heart cam 21 arrives first after the full tube is reached by the output pulse of the encoder 30, the pulse count value of the encoder 30 is reset. Thereafter, when the number of count pulses from the encoder 30 becomes the number of fine thread forming pulses, the control motor 24 is controlled in step 5 to rotate the middle roller, the back rollers 6, 7 and the rotation of the front roller 5. Is set to a preset fine yarn forming draft ratio. Thus, spinning of the fine thread portion S is started from the draft part 4 (FIG. 3).
(A), timing A in FIG.

In step 6, when the count pulse number of the encoder 30 indicates the valley of the heart cam 21 (FIG. 3B),
At timing B) in FIG. 4, the heart cam clutch 31 is disengaged in step 7 to stop the chase, and
And the clutch 41 is engaged, and the ring rail 10 is separated from the shaper feed and lowered. At this time, the starting end S1 of the fine thread portion S starts to be wound around the outer periphery of the full bobbin F as a starting point of the body winding Q1. During the descent, when it is determined from the spun length data from the pulsar 46 that the spun length from the start of the fine yarn forming draft has reached the length required for the tail winding and the trunk winding, the rotation of the control motor 24 is controlled. Then, the rotation ratio of the second and the back rollers 6, 7 with respect to the front roller 5 is returned to the reference draft ratio (step 8: timing C in FIG. 3C and FIG. 4). It is determined from the signal of the encoder 45 that the ring rail 10 has reached the tail winding position facing the yarn holding section 63, and the clutch 41 is disengaged (step 9: FIG. 3D: timing D in FIG. 4).
From that point, when it is determined from the spun length data of the pulser 46 that the preset tail winding length has been spun (step 10), the shaper feed clutch 42
At the winding start position S by the ring rail lift motor 43.
The ring rail 10 is moved up to S, the brake is applied to the main motor 2, and the machine base is stopped. The spindle 1 stops in synchronization with this.

By generating and winding the fine thread portion S in this manner, when the spindle is stopped,
The starting end S1 of the fine thread portion S is located at the beginning of winding of the body winding Q1, and the ending S2 of the fine thread portion S is located at the end of winding of the tail winding Q2 (FIG. 3 (e): timing E in FIG. 4). The thread portion S straddles the cutter 62. When the bobbin gripper of the tube changing device (not shown) grips the top of the full bobbin F and pulls it upwards, the thin thread portion S straddles the cutter. Compared to a case where a difficult yarn is cut with a thick count, the yarn is reliably cut with an extremely small force. After taking out the full bobbin F, the empty bobbin is fitted on the spindle 1, the heart cam clutch 31 is engaged, and the bobbin is restarted.

In the above embodiment, the front roller, the second roller and the back roller are divided, and the rotation ratio is controlled by separate motors to change the draft ratio. However, the middle roller and the back roller are divided from the front roller. Without using a gear drive system, a differential gear mechanism is interposed in the drive system, and usually all the draft rollers are rotated by a main motor at a reference draft ratio determined by the gear ratio of the differential gear mechanism. At the time of thread formation, the auxiliary motor connected to the auxiliary input shaft of the differential gear mechanism is rotated, and the rotation from the main motor and the rotation of the auxiliary motor are combined by the differential gear mechanism to rotate the draft part. The ratio may be the fine yarn forming draft ratio.

[0017]

As described above, according to the present invention, at a timing near the end of spinning, the draft ratio of the spun yarn is changed to form a fine yarn portion thinner than the yarn of the reference thickness, and the fine yarn portion is formed. When the spindle is stopped, it is positioned so as to straddle the cutter at the spindle base, and the bobbin is pulled out in that state.Thus, even with a thick thread, the thin thread part with low thread strength is cut by the cutter, and , And the power required for cutting can be greatly reduced as compared with the case of cutting with a thick thread. Further, in the present application, since the body winding and the tail winding, which are not used in the subsequent process, are formed as the fine thread portion, the fine thread portion is not mixed into the used thread portion, and the yarn quality does not deteriorate.

[Brief description of the drawings]

FIG. 1 is a diagram showing a drive system of a spinning machine embodying the present invention.

FIG. 2 is an operation flowchart.

FIG. 3 is an explanatory diagram of the operation of the body winding and the tail winding.

FIG. 4 is a diagram showing the relationship between the timing of each operation and the position of a ring rail.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Spindle 4 Draft part 10 Ring rail 62 Cutter 63 Thread holding part F Full bobbin L Spun yarn path length Q1 Body winding Q2 Bottom winding S Fine thread S1 Fine thread start end S2 Fine thread end

Claims (3)

[Claims] When the bobbin reaches a winding amount to be doffed, the ring rail is lowered to a tail winding position to perform a bobbin winding, and a yarn is held by a yarn holding portion of a spindle base to stop the spindle. In a yarn cutting method in a spinning machine in which a thread connected to the bobbin is cut off by pulling up a draft from a spindle, a draft part is changed during drafting in a spinning machine. In a possible configuration, the draft ratio of the draft part is changed at a timing near the end of spinning to form a fine thread portion, and when the spindle is stopped, the fine thread portion is at a position corresponding to the cutter. A yarn cutting method in a spinning machine, characterized in that: 2. The yarn in a spinning machine according to claim 1, wherein the draft ratio of the draft part is changed to the fine yarn forming draft ratio so that the yarn portion forming the body winding and the tail winding becomes the fine yarn portion. Cutting method. 3. The spout length is detected based on the rotation of the heart cam, and the spout length from the trough of the heart cam that arrives after the spinning amount to be doffed becomes the next trough portion.
During the rotation, when the spun yarn path length from the draft roller to the bobbin is left, the draft ratio of the draft part is changed from the standard draft ratio to the fine yarn forming draft ratio. 3. The yarn cutting method according to claim 2, wherein when the spinning length is spun, the draft length is returned to the reference draft ratio.