JPH0444627Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention (industrial application field) This invention is an open-end spinning unit that is equipped with a number of spinning units that twist and continuously draw out the fibers guided to the converging section in the rotor. This invention relates to a rotor drive device for a spinning machine.

(Prior Art) Generally, in this type of open-end spinning frame, the rotor is rotationally driven by pressing the rotation shaft of the rotor against a common drive belt for all spindles. This belt drive method has the disadvantage that the transmission efficiency between the belt and the drive pulley, guide pulley, or rotor rotating shaft is poor and power consumption per spindle is large. Furthermore, since a radial load is applied to the bearing that supports the rotating shaft of the rotor, there is a problem that the bearing wears out prematurely. When the rotor rotates at an extremely high speed, the above problem becomes more noticeable.

In order to solve this problem, Japanese Patent Publication No. 51-13778, published on May 4, 1975, proposes a device in which each rotor shaft is directly connected to an individual electric motor and driven. In this open-end spinning machine, as shown in Fig. 4, each individual electric motor M has three power sources.
Electric power is supplied from 1 through an inverter 32 as a variable frequency power source.

(Problems to be solved by the invention) In the conventional device, the rotation speed of each individual electric motor M is controlled by an inverter 32 common to all the spindles,
During normal spinning operation, the rotor is rotated at a very high speed, and during yarn piecing, the frequency of the inverter 32 is changed to a low frequency to lower the rotation of the individual electric motor M. For this reason, it is necessary to reduce the rotational speed of the rotors of all the spindles in order to join the threads of one spindle, resulting in a problem of reduced productivity. In order to perform the yarn splicing operation while the rotor is rotating at an ultra-high speed, the tolerance of the operation timing of each mechanism for performing the yarn splicing operation becomes extremely small, making it difficult to splice the yarn.
In particular, it becomes more difficult to splice yarn using automatic machines.

Structure of the invention (means for solving the problems) In order to solve the above problems, in this invention, each rotor shaft is directly connected to a pole number switching electric motor driven by a common variable frequency power supply for all spindles,
An electromagnetic switch for switching the number of poles of the electric motor was provided, and a control section for controlling the electromagnetic switch was also provided.

(Function) In this device, during normal spinning, the pole number switching electric motor that drives the rotor of each spinning unit is driven to rotate at high speed by a variable frequency power supply common to all spindles. The pole number switching motor for each weight can be driven to rotate at a low speed by switching the number of poles independently from other weights via an electromagnetic switch controlled by the control unit.
Therefore, during yarn splicing work, the number of poles of the electric motor for only the spinning spindle is changed, and after shifting to low speed rotation, the yarn splicing work is performed.

(Example) Examples 1 to 3 of this invention are explained below.
This will be explained according to the diagram. The rotor shaft 2 of each spinning unit 1 is directly connected to an independent pole number switching electric motor Mp, and the pole number switching electric motor Mp is connected to a power source 3 common to all spindles.
and is connected to an inverter 4 as a variable frequency power source. The pole number switching motor Mp of this embodiment is a single winding type pole number switching motor, and has two sets of connection terminals U1, V1, and V1 for passing current through the coil.
It has W1, U2, V2, and W2. Each connection terminal
Each wiring connecting U1, V1, W1, U2, V2, W2 and inverter 4 has an electromagnetic switch MS1.
1, MS12 is connected. One connection terminal
A short-circuit electromagnetic switch MS1 is installed in the middle of the wiring connecting U1, V1, W1 and the one electromagnetic switch MS12.
1A is connected. Also, the other electromagnetic switch
A series circuit of an electromagnetic switch MS11B and a resistor 5 is connected in parallel to MS11.

Each spinning unit 1 is provided with a yarn breakage detection device 6 having a detection section 6a, and each of the electromagnetic switches MS
11, MS11A, MS11B, MS12 and the yarn breakage detection device 6 receive the yarn breakage detection signal from the yarn breakage detection device 6 and the signal from the automatic yarn splicing machine 7 and switch the respective electromagnetic switches MS11, MS11A, MS11.
B, is connected to the control unit 8 that controls the MS 12. Further, the automatic yarn splicing machine 7 is capable of transmitting and receiving signals to and from the control section 8 at the yarn splicing stop position corresponding to each spinning unit 1.

Next, the operation of the apparatus configured as described above will be explained. During normal spinning operation, the electromagnetic switch
MS11 and the short-circuit electromagnetic switch MS11A are held in a closed state, and the pole number switching motor Mp is supplied with current from the connection terminals U2, V2, and W2 and acts as a two-pole motor. The rotor is driven to rotate at high speed. If yarn breakage occurs in this state, a yarn breakage detection signal is sent from the yarn breakage detection device 6 of the spinning unit 1 where the yarn breakage occurred to the control unit 8, and the control unit 8 switches the electromagnetic switch that had been closed until then.
When opening MS11 and MS11A, the electromagnetic switch
Close MS12. This allows pole number switching motors to
Current is supplied to Mp from connection terminals U1, V1, and W1, and it operates as a four-pole motor, reducing its rotational speed by half. In this state, the automatic yarn splicing machine 7 stops at a position corresponding to the spinning unit 1 in the broken yarn state for yarn splicing work, and performs the yarn splicing work. Since the rotational speed of the rotor is half of the rotational speed during normal spinning operation, the tolerance range for yarn splicing timing is widened, making yarn splicing work easier.

When the yarn splicing work by the automatic yarn splicing machine 7 is completed in this state, a yarn splicing completion signal is sent from the automatic yarn splicing machine 7 to the control unit 8, and based on the signal, the control unit 8 opens the electromagnetic switch MS12 and shorts it. Close the electromagnetic switch MS11A for the rotation speed and the electromagnetic switch MS11B for controlling the rise of the rotation speed. As a result, the connection terminals U1, V1, and W1 are short-circuited again in the pole number switching motor Mp.
Current is supplied from U2, V2, and W2, and it acts as a two-pole motor. At this time, since power is supplied to the pole number switching electric motor Mp through the resistor 5, the rotational speed rises slowly, making it easier to control the winding side. Then, after reaching a predetermined high speed rotation, the electromagnetic switch MS11 is closed by a signal from the control unit 8, and the electromagnetic switch MS11B is opened, and the pole number switching electric motor Mp enters a normal operating state.

Note that this invention is not limited to the above-described embodiment; for example, instead of switching the pole number of the pole number switching motor Mp at the same time as yarn breakage, the automatic yarn splicing machine 7 may correspond to the yarn breakage spinning unit 1. The structure may be such that the number of poles is changed after stopping at the position. In addition, without providing a series circuit between the electromagnetic switch MS11B and the resistor 5, the electromagnetic switch for two-pole operation can be installed immediately after yarn piecing is completed.
The MS11 may be in the ON state. In this case, the rotational speed rises suddenly. Furthermore, the pole number switching of the pole number switching electric motor Mp is not limited to two poles and four poles, but may be configured to switch between other pole numbers.

Effects of the invention As detailed above, according to this invention, even though the electric motor of each spinning unit is driven via a common variable frequency power source for all spindles, when splicing yarn due to yarn breakage, the spinning Since the rotational speed of the electric motor of the spinning unit can be lower than the rotational speed during normal spinning operation, the tolerance range for yarn splicing timing is widened, making it possible to easily and reliably perform yarn splicing work. It has a great effect.

[Brief explanation of the drawing]

Figures 1 to 3 show an embodiment of this invention, in which Figure 1 is an electric circuit diagram, Figure 2 is a diagram showing the connection state of the coil and connecting terminal, and Figure 3 is a thread FIG. 4 is a diagram showing the rotation speed of the rotor and the state of each electromagnetic switch from the time of yarn breakage to the time of return to normal operation after completion of yarn splicing, and FIG. 4 is an electric circuit diagram of the conventional device. Spinning unit 1, inverter 4 as a variable frequency power source, resistor 5, automatic splicing machine 7, control unit 8, pole number switching motor Mp, electromagnetic switches MS11, MS11
A, MS11B, MS12.

Claims (1)

[Scope of utility model registration request] In an open-end spinning machine equipped with a number of spinning units that twist and continuously draw out the fibers led to the convergence section within the rotor, each rotor shaft is driven by a variable frequency power supply common to all spindles. A rotor drive device for an open-end spinning machine, which is directly connected to a pole number switching motor, and includes an electromagnetic switch for switching the number of poles of the motor, and a control section for controlling the electromagnetic switch.