JPH083824A - Stopping of spinning machine and stopping-controlling apparatus - Google Patents

Abstract

PURPOSE:To reduce the yarn breakage during descending of a ring rail for forming inclination winding having a specific range of length. CONSTITUTION:A front roller 1 and a spindle 4 of a spinning machine are driven through a driving shaft 3, etc., by a main motor. A line shaft 7 is placed in the longitudinal direction of the machine and normally and reversely driven by a servo-motor 12. The ring rail 8 is supported by a porker pillar 10 whose screw 10a is engaged with a nut 11, and it is lifted and lowered through a screw gear 9 and the nut 11 by the normal and reverse rotation of the line shaft 7. A tension sensor S2 is placed below a snail wire 15. A controller 13 adjusts the rotating speed of the servo-motor 12 in such a manner as to change the descending speed of the ring rail 8 keeping the tension variance in the winding of yarn Y at or below a specific value based on the signal of the tension sensor S2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of stopping a spinning machine such as a ring spinning machine and a ring twisting machine, and a stop control device. More specifically, the lifting drive system is driven by a motor different from the roller part and the spindle drive system. The present invention relates to a stopping method and a stopping control device for doffing a spinning machine.

[0002]

2. Description of the Related Art In order to prevent yarn unevenness and yarn breakage, a ring spinning machine keeps a constant relationship between the amount of yarn fed from a draft device, that is, the rotation speed of a front roller and the rotation speed of a spindle. Driven. In addition, in order to ensure that the yarn is automatically wound around the empty bobbin at the time of restarting after changing pipes, the ring rail is lowered to the bottom bunch winding position when stopping for doffing, and the bottom bunch is placed at the bottom of the spindle or the bobbin. A roll is formed.

In addition to the bottom bunch winding, a top bunch winding may be formed in order to facilitate the finding in the winder in the next step. When forming the top bunch winding, when the machine is stopped, the ring rail is first raised to form the top bunch winding on the uppermost part of the bobbin, and then the bottom bunch winding is formed. In either case, the ring rail is lowered at a high speed from the highest position to the bottom bunch winding position, and the inclined winding is formed on the outer circumference of the yarn.

In order to smoothly perform the pipe replacement work and the yarn picking work with the winder, the number of turns is preferably 1 to 3 when forming the inclined winding. Generally, a constant speed electric motor is used for the main motor that drives the spindle and draft part, and the inclined winding is formed by the self-weight of the ring rail during inertial rotation when the main motor is stopped from the normal winding operation state ( Automatic descent). Since the descent of the ring rail is started at the same time that the main motor rotates by inertia, it is difficult to adjust the length of the inclined winding to a desired length depending on the spinning conditions. In particular, this problem becomes more noticeable because the rotational speed of the spindle is high immediately after inertia rotation due to the increase in speed of the spinning machine in recent years.

To solve this problem, Japanese Patent Laid-Open No. 63-
Japanese Patent No. 145430 discloses an inclined winding forming method in which a rotation speed of a main motor is maintained at a constant speed lower than a normal spinning speed when stopped for doffing, and then a ring rail is lowered to a bottom bunch winding position at a constant speed. It is disclosed. This publication also discloses a configuration in which the ring rail is driven by a motor other than the main motor, instead of being automatically lowered.

On the other hand, in a spinning factory, when doffing a large number of spinning machines installed in an automatic machine, in order to improve the operating efficiency of the automatic machine, one automatic machine takes charge of a plurality of spinning machines and each spinning machine is operated. The doffing of the spinning machine is performed every predetermined time. Therefore, during the winding operation, the traveler is replaced,
When the machine stand is stopped due to a machine stand failure or the like, the doffing is carried out in a state where the yarn is small at a predetermined doffing time. When the ring rail performs the doffing stop operation similar to when the ring rail is full, there is a problem that thread breakage occurs frequently.
In order to prevent this frequent occurrence of yarn breakage, JP-A-63-2567 is used.
Japanese Laid-Open Patent Publication No. 23-52 discloses a method of lowering the ring rail so as to reduce the relative speed difference between the rotation speed of the spindle and the traveling speed of the traveler when lowering the ring rail to the bottom bunch winding position.

[0007]

However, Japanese Patent Laid-Open No. Sho 63-63
In the method disclosed in Japanese Patent No. 145430, yarn breakage may occur depending on spinning conditions. When the cause of this was investigated, it was estimated that thread breakage occurred when the fluctuation of the thread tension due to the fluctuation of ballooning when the ring rail was descending was too large. That is, when forming the inclined winding, the ring rail descends from the highest position to the bottom bunch winding position in a short time, so that the distance between the traveler and the snell wire changes abruptly and the fluctuation of the ballooning increases. It is considered that yarn breakage is likely to occur due to the abrupt change in tension at that time. Also, JP-A-63-2
The method disclosed in Japanese Patent No. 56723 solves the so-called frequent occurrence of yarn breakage during so-called doffing on the way, and cannot be applied to doffing when the pipe is full.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a ring rail for forming an inclined winding of a predetermined length when a machine stand for doffing is stopped. It is an object of the present invention to provide a stopping method and a stopping control device for a spinning machine, which can reduce the occurrence of yarn breakage during the descent.

[0009]

In order to achieve the above object, according to the invention of claim 1, a lifting drive system is driven by a motor different from a spindle drive system, and a machine stand for doffing a spinning machine is stopped. At this time, when the ring rail is lowered from the highest position to the bottom bunch winding position to form the slant winding, the motor of the lifting drive system is drive-controlled so as to reduce the fluctuation of the winding tension of the yarn. The descent speed is changed.

According to the invention described in claim 2, in a spinning machine in which the lifting drive system is driven by a motor different from the spindle drive system, a variable speed motor for driving the lifting drive system and fluctuations in the yarn winding tension And a variable speed motor for changing the lowering speed of the ring rail so that the fluctuation amount of the winding tension of the yarn becomes a predetermined value or less based on the detection signal of the tension fluctuation detecting means. And a control means for driving and controlling the.

According to the invention of claim 3, in a spinning machine in which the lifting drive system is driven by a motor different from the spindle drive system, the rotation speed of the variable speed motor for driving the lifting drive system and the spindle is detected. A detection means, a position detection means for detecting the position of the ring rail, and a relational expression or a database that indicates the relationship between the rotation speed of the spindle and the position of the ring rail and the appropriate descent speed of the ring rail in correspondence with the spinning conditions are stored. The storage means, the control means for driving and controlling the variable speed motor based on the detection signals of the detection means and the position detection means, and the relational expression or the database stored in the storage means are provided.

[0012]

In the invention described in claim 1, the lifting drive system is driven by a motor different from the spindle drive system. When the machine stand for doffing is stopped, the ring rail is lowered from the uppermost position to the bottom bunch winding position in order to form an inclined winding. At this time, the motor of the lifting drive system is drive-controlled so as to reduce the fluctuation of the winding tension of the yarn, and the descending speed of the ring rail changes. As a result, occurrence of yarn breakage due to excessive tension fluctuation is suppressed.

According to the second aspect of the invention, the lifting drive system is driven by a motor different from the spindle drive system.
When the machine stand for doffing is stopped, the ring rail is lowered from the uppermost position to the bottom bunch winding position in order to form an inclined winding. At this time, the fluctuation of the winding tension of the yarn is detected by the tension fluctuation detecting means. Then, the control means drives and controls the variable speed motor based on the detection signal of the tension fluctuation detecting means so that the tension fluctuation amount of the yarn becomes equal to or less than a predetermined value, thereby changing the descent speed of the ring rail.

According to the third aspect of the invention, the rotation speed of the spindle is detected by the detecting means, and the position of the ring rail is detected by the position detecting means. When the machine stand for doffing is stopped, the ring rail is lowered from the highest position to the bottom bunch winding position to form an inclined winding. At this time, the control means, based on the detection signals of the detection means and the position detection means, and the relational expression or the database stored in the storage means, adjusts the variable speed so that the ring rail descends at an appropriate speed corresponding to the spinning condition. Drive control of the motor.

[0015]

【Example】

(First Embodiment) An embodiment of the present invention will be described below with reference to FIGS.

As shown in FIG. 1, a gear 2 is fitted to an end of a rotary shaft 1a of a front roller 1 which constitutes a draft device. The rotary shaft 1a is rotationally driven via a gear train (not shown) arranged between a gear 2 and a driving shaft 3 which is rotationally driven by a main motor M as a spindle driving motor. ing. The spindle 4 is rotatably driven via a spindle tape (not shown) wound around a chin pulley 5 fixed to the driving shaft 3. The front roller 1 and the spindle 4 are rotated so that the feeding amount (spinning amount) of the fleece from the front roller 1 and the yarn winding amount of the spindle 4 are always the same amount. The rotation speed ratio between the two is set according to the spinning conditions (twisting number). A variable speed motor driven through an inverter 6 is used as the main motor M, and the main motor M is an electromagnetic brake MB.
It has. A sensor S1 that outputs a pulse signal corresponding to the rotation of the front roller 1 is arranged near the gear 2.

The lifting drive system is adapted to vertically move a ring rail 8 and a lappet angle (not shown) via a line shaft 7. The line shaft 7 is arranged along the longitudinal direction of the spinning machine base, and screw gears 9 (only one is shown in FIG. 1) are integrally rotatably fitted at predetermined intervals. The ring rail 8 is composed of a plurality of poker pillars 10.
(Only one is shown in FIG. 1). The poker pillar 10 is movably supported in a vertical direction on a machine frame (not shown), and a screw portion 10a is formed in a lower portion thereof. The screw portion 10a is screwed to a nut body 11 rotatably supported at a predetermined height position of the machine base frame. A screw gear (not shown) that meshes with the screw gear 9 is integrally formed on the outer periphery of the nut body 11.

The line shaft 7 is connected to the drive shaft of the servomotor 12 via a gear train (not shown). The servo motor 12 is drive-controlled by a control device 13 as a control means via a servo driver 14. The servo motor 12 has a rotary encoder 12a built therein. The rotary encoder 12a constitutes a position detecting means of the ring rail 8. The line shaft 7 is driven by the servo motor 12, and the rotation speed and the rotation direction can be freely changed. Line shaft 7, poker pillar 10, nut body 11, servo motor 12, and control device 1
A lifting drive system is constituted by 3.

Below the snell wire 15 supported by the lappet angle, the traveler 1 sliding on the ring 8a.
Tension sensor S2 as tension fluctuation detection means for detecting fluctuations in the winding tension of the yarn Y reaching the snell wire 15 via 6
Is provided. The tension sensor S2 is not provided on all the weights but is provided only on a specific weight, and the tension sensor S2 may be provided on only one weight.

As shown in FIG. 2, the control unit 13 includes a central processing unit (hereinafter referred to as CPU) as a computing unit and a control unit.
17). The control device 13 includes a program memory 18 as a storage unit, a work memory 19, an input device 20, an input / output interface 21, a main motor drive circuit 22, a servo motor drive circuit 23, and an electromagnetic brake excitation / demagnetization circuit 24. The CPU 17 operates based on predetermined program data stored in the program memory 18. The program memory 18 is a read-only memory (ROM), and stores the program data and various data necessary for its execution. The work memory 19 is composed of a readable and rewritable memory (RAM), and is used for data input by the input device 20 and the CPU 1.
The calculation processing result and the like in 7 are temporarily stored. Data such as spinning condition data, stopping operation condition data, and an upper limit value of the variation amount of the winding tension at the time of forming the inclined winding are input by the input device 20.

The CPU 17 is connected to the sensor S1 and the tension sensor S2 via the input / output interface 21. The CPU 17 integrates the spinning amount based on the output signal from the sensor S1. The CPU 17 is connected to the rotary encoder 12a via the input / output interface 21 and calculates the movement amount and position of the ring rail 8 based on the output signal from the rotary encoder 12a. The CPU 17 receives the electromagnetic brake MB via the electromagnetic brake excitation / demagnetization circuit 24.
Control the excitation and demagnetization.

Next, the operation of the apparatus configured as described above will be described. Prior to the operation of the machine stand, spinning conditions such as fiber type, spun yarn count, number of twists, spindle rotation speed during normal spinning operation, spinning length, lift length, chase length, etc., and stop operating conditions, The input device 20 inputs data such as the upper limit value of the fluctuation amount of the winding tension when the inclined winding is formed. The upper limit is experimentally obtained in advance and is set to a value such that yarn breakage does not occur even if the value is slightly exceeded. Also, the upper limit value changes mainly depending on the fiber type and the spun yarn count. In addition to the difference between cotton, synthetic fiber, and mixed spinning, the fiber type means the difference between carded cotton and combed cotton even if they are the same cotton.

During normal operation, the control device 13 is operated by the input device 20.
The servo motor 12 is driven and controlled in synchronization with the main motor M in accordance with the spinning conditions input by the above and stored in the working memory 19. When the servomotor 12 is driven, the line shaft 7 is rotated via the gear train, and the nut body 11 is rotated via the screw gear 9. And the nut body 11
The poker pillar 10 screwed to the upside or downside is moved, and the ring rail 8 or the like is moved up and down. The ring rail 8 and the like are moved upward when the servomotor 12 rotates in the forward direction, and are moved downward when the servomotor 12 rotates in the reverse direction. The yarn Y sent out from the front roller 1 is wound around the bobbin B via the snell wire 15, the tension sensor S2 and the traveler 16.

When the spinning and winding operations are continued and the integrated spinning amount reaches a predetermined value, the CPU 17 executes the doffing stop operation according to the flowchart of FIG. The CPU 17 first decelerates the main motor M to a predetermined low speed via the inverter 6 in step S11. Next, in step S12, the CPU 17 drives the servomotor 12 in the normal direction so as to rapidly raise the ring rail to the top bunch winding position, and then,
The driving of the servo motor 12 is stopped for a predetermined time. As a result, a top bunch winding is formed.

Next, in step S13, the CPU 17 starts the descent of the ring rail 8 from the top bunch winding position at a speed higher than the lifting speed of the ring rail 8 during normal operation.
That is, the servo motor 12 is driven in reverse. At this time, the descending speed is adjusted so that the number of inclined windings wound around the bobbin B is 2 while the ring rail 8 reaches the bottom bunch winding position. The main motor M is rotated at a predetermined low speed before the descent of the ring rail 8 is started.
The inclined winding number is determined by the spindle rotation speed during the lowering of the ring rail 8 from the top bunch winding position to the bottom bunch winding position, the feeding amount (spinning amount) of the fleece from the front roller 1 and the descending speed of the ring rail 8. The CPU 17 calculates the rotation speed of the spindle 4 from the output signal of the sensor S1 and drives and controls the servo motor 12 so that the descending speed of the ring rail 8 falls within a range where a predetermined number of inclined turns is achieved.

In step S14, the CPU 17 calculates the fluctuation amount of the winding tension from the output signal of the tension sensor S2 (tension fluctuation amount calculation step), and compares the value with a preset upper limit value (step S15). . If the amount of fluctuation exceeds the upper limit value, the servo motor 12 is drive-controlled in step S16 so as to reduce the descending speed of the ring rail 8 by a predetermined ratio (descent speed adjusting step). Next, in step S17, it is determined whether or not the ring rail 8 has reached the bottom bunch winding position, and if so, the driving of the servo motor 12 is stopped. If not reached, step S1
Return to 4. As a result, while the ring rail 8 descends from the top bunch winding position to the bottom bunch winding position, an inclined winding having a predetermined range of length that does not hinder the doffing and rewinding by the winder is formed. Then, the fluctuation amount of the winding tension of the yarn Y is adjusted to a range that does not cause the yarn breakage, and the yarn breakage at the time of inclined winding formation is avoided.

The CPU 17 controls the servo motor 12 and the main motor M after the ring rail 8 reaches the bottom bunch winding position.
Is stopped and the electromagnetic brake MB is excited after a predetermined time (step S18). as a result,
A predetermined number of bottom bunch windings are formed at the bottom bunch winding position, and the main motor M is completely stopped to complete the stop operation. When the automatic pipe changer is equipped with the tight fitting release device, it does not hinder the tight fitting release device from entering between the lower end of the bobbin and the spindle 4 after the bottom bunch winding is formed. After the ring rail 8 is raised to the position (primary rising position), the main motor M is completely stopped.

When doffing a plurality of spinning machines with one doffing machine (replacement machine), doffing is performed before the yarn is full at a preset doffing time. There are cases.
In that case, when the CPU 17 reaches the predetermined doffing time,
The servo motor 12 and the main motor M are drive-controlled to perform the stop operation in substantially the same manner as when the full pipe is stopped.

Further, in this embodiment, when the ring rail is lowered from the highest position to the bottom bunch winding position, the rotation speed of the spindle is maintained at a predetermined speed lower than the rotation speed during normal operation. Therefore, the fluctuation amount of the winding tension is adjusted only by changing the descending speed of the ring rail 8, which simplifies the control.

(Second Embodiment) Next, a second embodiment will be described.
In this embodiment, the tension sensor S2 is not provided, and the control program for performing the stop operation is different from that of the above-described embodiment, and other configurations are basically the same. The sensor S1 also plays a role as a detection unit that detects the rotation speed of the spindle 4, and the CPU 17 calculates the rotation speed of the spindle 4 based on the output signal of the sensor S1.
The program memory 18 stores a relational expression or a database showing the relationship between the spindle rotation speed and the position of the ring rail at the time of forming the inclined winding and the proper lowering speed of the ring rail. The creation of the database was carried out experimentally by changing the spinning conditions such as the fiber type and the spinning number, changing the rotation speed of the spindle 4 and the descending speed of the ring rail 8, and examining the occurrence of yarn breakage. Desired.

When the CPU 17 performs the stop operation,
The servo motor 12 is drive-controlled based on the detection signals of the sensor S1 and the rotary encoder 12a and the relational expression or database stored in the program memory 18. That is, the CPU 17 obtains the appropriate spindle rotation speed and ring rail lowering speed at each position of the ring rail 8 from the relational expression or the database in accordance with the spinning conditions. Then, the CPU 17 calculates the position of the ring rail 8 from the output signal of the rotary encoder 12a,
The main motor M is drive-controlled to have an appropriate spindle rotation speed corresponding to that position, and the servomotor 12 is drive-controlled to have an appropriate descending speed. Therefore, also in this embodiment, the inclined winding having a length within a predetermined range is formed without a large change in tension.

When forming the inclined winding, the rotation speed of the spindle 4 is decelerated to a constant speed lower than that during normal operation before the ring rail 8 is started to descend, and the ring rail 8 is descended in this state. , Main motor M and servo motor 12
The drive control of is easy. However, the ring rail 8 may be lowered while decelerating the main motor M.

The present invention is not limited to the above embodiment, but may be embodied as follows, for example. (1) In the first embodiment, the drive control may be performed so that the main motor M is decelerated at a predetermined deceleration gradient when the ring rail 8 descends from the top bunch winding position. Further, when a constant speed electric motor is used as the main motor M and the ring rail 8 is lowered from the top bunch winding position during the stop operation, the power supply to the main motor M is stopped and the ring rail 8 is rotated during inertial rotation of the main motor M. You may go down.

(2) As the lifting drive system motor, a variable speed motor whose speed is controlled via an inverter is used in place of the servo motor 12, and a pair of electromagnetic clutches are provided between the output shaft and the line shaft 7. A mechanism for changing the rotation direction of the line shaft 7 by exciting and demagnetizing may be provided.

(3) In the first embodiment, when obtaining the data of the upper limit value of the fluctuation amount of the winding tension, instead of actually operating the machine stand for each fiber type and spun yarn count, spun yarn is used. The upper limit may be set based on the value of the amount of tension fluctuation that causes yarn breakage by applying tension to the. In this case, the database can be created more easily than the method in which the machine is actually operated for each different spinning condition to create the database.

(4) As in the second embodiment, in the device configured to control the descending speed of the ring rail 8 at the time of the stop operation based on the database stored in the program memory 18, the fiber type as the spinning condition, In addition to the spinning count, the number of twists and the yarn diameter may be added to create a database.
In this case, since the proper descending speed of the ring rail 8 is set in consideration of the number of twists and the yarn diameter, the ring rail 8 is descended at a more suitable speed corresponding to the spinning condition, and the desired length is obtained. A slanted winding is formed.

(5) Instead of the program memory 18, a non-volatile RAM having a backup power source may be used as the storage means for storing the database or the relational expression. In this case, the database can be easily modified or added.

(6) As a driving means for moving the ring rail 8 up and down, like the device disclosed in Japanese Utility Model Publication No. 3-29334, the poker pillar 10 that supports the ring rail 8 is used.
It is also possible to form a rack in the lower part of the above and attach a pinion to the line shaft 7 instead of the screw gear 9.

(7) The present invention may be embodied in a spinning machine equipped with a lifting device for moving up and down a ring rail or the like on the basis of swinging by a heart cam. In this case, the actual fair 6-4
Like the device disclosed in Japanese Patent Laid-Open No. 62-62, the ring rail is moved up and down independently of the draft drive system side by a swing motor when the pipe is fully stopped. Therefore, in the case of this configuration, the present invention can also be applied to an existing spinning machine stand that moves a ring rail or the like up and down using a heart cam.

(8) Other than the rotary encoder may be used as the position detecting means of the ring rail 8. For example, a so-called magnet scale in which a large number of permanent magnets are alternately arranged with their N poles and S poles is arranged in the vicinity of the ascending / descending range of the ring rail, and the detection unit is fixed to the ring rail so as to be movable integrally. A device having a configuration may be adopted. Further, a linear potentiometer may be used as the movement amount detecting means. The rotary encoder may be mounted at any suitable position as long as it is a component that rotates in synchronization with the rotation of the line shaft.

(9) It may be applied to a stopping method in which only the bottom bunch is formed without forming the top bunch at the time of stopping due to full pipe and at the time of stopping doffing on the way. (10) Instead of driving the spindle 4 with the spindle tape wound around the chin pulley 5, it may be driven with a tangential belt. It may also be applied to a ring twisting machine.

Inventions other than those described in the claims that can be grasped from the above-mentioned embodiments and modifications will be described below together with their effects. (1) In the stopping method according to the first aspect, when the ring rail is lowered from the highest position to the bottom bunch winding position, the rotation speed of the spindle is maintained at a predetermined speed lower than the rotation speed during normal operation. In this case, the change amount of the winding tension of the yarn can be adjusted only by changing the descending speed of the ring rail, which simplifies the control.

[0043]

As described in detail above, the first to third aspects of the invention are described.
According to the invention described in (1), in the spinning machine in which the lifting drive system is driven by a motor different from the spindle drive system, a ring for forming an inclined winding of a predetermined range length when the machine stand for doffing is stopped. It is possible to reduce the occurrence of yarn breakage when the rail descends.

Further, in the invention described in claim 2, since the amount of change in the winding tension is detected and the descending speed of the ring rail is adjusted correspondingly, even when the doffing on the way or the diameter of the pipe thread is changed. , Easy to handle.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a drive system of a first embodiment embodying the present invention.

FIG. 2 is a block diagram illustrating an electrical configuration of a control device.

FIG. 3 is a flowchart illustrating an operation.

[Explanation of symbols]

4 ... Spindle, 7 ... Line shaft that constitutes a lifting drive system, 8 ... Ring rail, 12 ... Servo motor as a variable speed motor that constitutes a lifting drive system,
12a ... Rotary encoder as position detecting means, 1
3 ... Control device as control means, 17 ... CPU as calculation means and control means, 18 ... Program memory as storage means, S1 ... Sensor as detection means, S2 ... Tension sensor as tension fluctuation detection means.

Claims (3)

[Claims] 1. When the lifting drive system is driven by a motor different from the spindle drive system and the machine stand for doffing the spinning machine is stopped, the ring rail is moved from the uppermost position to the bottom bunch winding position to form an inclined winding. When lowering
A stopping method in a spinning machine, which controls the motor of a lifting drive system to change the descending speed of the ring rail so as to reduce the fluctuation of the winding tension of the yarn. 2. A spinning machine in which the lifting drive system is driven by a motor different from the spindle drive system, a variable speed motor for driving the lifting drive system, and a tension fluctuation detecting means for detecting fluctuations in the winding tension of the yarn. Control means for driving and controlling the variable speed motor so as to change the descending speed of the ring rail so that the fluctuation amount of the winding tension of the yarn becomes equal to or less than a predetermined value based on the detection signal of the tension fluctuation detecting means. Stop control device for spinning machine. 3. In a spinning machine in which the lifting drive system is driven by a motor different from the spindle drive system, a variable speed motor for driving the lifting drive system, a detection means for detecting the rotation speed of the spindle, and a ring rail position are set. A position detecting means for detecting, a storage means for storing a relational expression or a database showing the relationship between the rotation speed of the spindle and the position of the ring rail and the proper lowering speed of the ring rail corresponding to the spinning condition; A stop control device for a spinning machine, which is provided with control means for driving and controlling the variable speed motor based on a detection signal of the position detection means and a relational expression or database stored in the storage means.