JPH057276Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to an edge tracking device for a tenter used for tentering a fabric.

(Prior art) When the edge position of the fabric supplied to the tenter shifts from side to side, a tenter rail located on the entrance side of the tenter is used to ensure that the edge of the fabric is always held securely on the tenter clip or pin plate. A selvage tracking device is used that slides the tenter rail from side to side according to the displacement of the selvage of the fabric. In order to change the sliding speed, a DC motor is used to slide the tenter rail, the direction and magnitude of displacement of the edge of the fabric relative to the neutral position are detected, and the DC motor is activated according to the direction of this displacement. It is known to rotate forward or reverse, and to increase or decrease the forward rotation speed or reverse rotation speed depending on the magnitude of the displacement.

(Problem to be solved by the invention) However, since the above device used a DC motor for sliding the tenter rail, the commutator connected to the armature winding and the carbon Electric current is passed through the armature windings by making contact with the brushes. Therefore, while the armature is rotating, the commutator and carbon brushes constantly rub against each other, causing failures due to poor contact, and it is necessary to replace worn carbon brushes. Therefore, their handling and maintenance were troublesome.

This idea eliminates the need for carbon brushes by using a combination of an induction motor and an inverter for sliding the tenter rail, and also changes the sliding speed of the tenter rail depending on the magnitude of the displacement of the edge. This is what I did.

(Means for Solving the Problems) In this invention, a feeler bar is brought into contact with the edge of the fabric just before it is held in the tenter chain on the fabric entrance side of the tenter, and an electric signal of a magnitude corresponding to the displacement of the feeler bar is transmitted. An output edge feeler is provided, and upon receiving the output signal of the edge filler, the edge feeler outputs a forward rotation speed signal and a reverse rotation speed signal proportional to the positive direction displacement and negative direction displacement, respectively, with respect to the neutral point of the feeler bar. At the same time, a preamplifier that outputs a reverse rotation command signal when outputting the reverse rotation speed signal is connected, and the output terminals of the forward rotation speed signal and reverse rotation speed signal of this preamplifier are connected to the power supply of the induction motor for sliding the tenter rail on the entrance side. It is connected to a speed signal terminal of a speed control inverter interposed in the circuit, and an output terminal of the preamplifier for a reverse rotation command signal is connected to an input terminal for reverse command of the inverter.

(Function) The output signal of the edge filler is converted into a control signal for the inverter by the preamplifier, and the feeler bar of the edge feeler is displaced in the positive direction with respect to the neutral point, that is, inward of the fabric width. When this occurs, a forward rotation speed signal with a voltage proportional to this amount of displacement is input to the inverter to rotate the induction motor in the forward direction, causing the entrance side tenter rail to slide outward at a speed proportional to the amount of displacement. On the other hand, when the feeler bar is displaced in the opposite direction to the neutral point, that is, outward of the fabric width, a reverse speed signal with a voltage proportional to the amount of displacement and a reverse rotation command to reverse the induction motor are generated. A signal is input to the inverter to rotate the induction motor in the opposite direction, causing the entrance tenter rail to slide inward at a speed proportional to the displacement.

(Example) In FIG. 1, a tenter chain 2 runs perpendicularly to the plane of the paper in a chain guide groove 1a of a tenter rail 1, and a pin plate holder is attached to a sliding plate 3 fixed to each link of this tenter chain 2. A pin plate 5 is fixed via 4, and the fabric F is locked to this pin plate 5 on the tenter entrance side. The tenter rail 1 is formed to be slidable in the left-right direction, and is moved to follow the edge of the fabric F by rotating a screw shaft (not shown) in the left-right direction.

The selvage end filler 10 has a downward feeler bar 11, and is biased so that the lower end of the feeler bar 11 lightly contacts the selvage end of the fabric F. Furthermore, the edge feeler 10 has a built-in non-contact displacement sensor that detects the inclination angle of the feeler bar 11, and outputs an electrical signal of a voltage corresponding to the displacement of the feeler bar 11.

The preamplifier 20 receiving the output signal of the ear end feeler 10 includes four operational amplifiers OP ₁ , OP ₂ , OP ₃ , OP ₄ and two limit switches LS ₁ , LS ₂ as shown in FIG. The input terminal A connected to the edge filler 10 is the positive phase input terminal of the first operational amplifier OP ₁ , the negative phase input terminal of the second operational amplifier OP ₂ , and the negative phase input terminal of the third operational amplifier OP ₃ . Each is connected to the input terminal via a first resistor _R1 .

The positive phase input terminal and the negative phase input terminal of the first operational amplifier OP ₁ are respectively grounded via the second resistor R ₂ , and the output terminal is connected to the rectifying element K, the first limit switch LS 1 and the second limit switch LS ₁ arranged in series. 1 resistance R ₁
It is connected to the anti-phase input terminal of the fourth operational amplifier OP ₄ via. Then, _{a first}
Resistor R ₁ is connected, and the graph in Figure 3 (however,
The horizontal axis represents the displacement signal input from the ear end filler 10 to the input terminal A of the preamplifier 20, and the vertical axis represents the output signal at point B between the rectifying element K and the first limit switch _LS1 . ), among the displacement signals, only the reverse rotation speed signal is output to the point B. In addition, the first limit switch LS ₁ is
This is a switch that sets the limit when the tenter rail 1 slides inward in the width direction, and opens when this limit is reached.

Further, the positive phase input terminal of the second operational amplifier OP ₂ is grounded via the first resistor R ₁ , and the output terminal is
Rectifier K and second limit switch arranged in series
The fourth operational amplifier via LS ₂ and the first resistor R ₁
Connected to the negative phase input terminal of OP ₄ . And the second
A first resistor _R1 is connected between the negative phase input terminal of the operational amplifier _OP2 and the second limit switch _LS2 , and the fourth
The graph in the figure (however, the horizontal axis is the displacement signal input from the ear end feeler 10 to the input terminal A of the preamplifier 20, and the vertical axis is the output signal at point C between the rectifying element K and the second limit switch LS ₂₎ . Take it as the axis.)
As shown in the figure, only the normal rotation speed signal among the displacement signals is outputted to the point C. The second limit switch _LS2 is a switch that sets a limit when the tenter rail 1 slides outward in the width direction, and is opened when this limit is reached.

Further, the positive phase input terminal of the third operational amplifier OP ₃ is grounded via the first resistor R ₁ , and the output terminal is
Grounded via photocoupler PC. and,
A rectifying element K is connected between the negative phase input terminal of the third operational amplifier OP ₃ and the photocoupler PC, and the graph shown in FIG. The displacement signal is plotted on the horizontal axis, and the output signal at the output terminal D of the third operational amplifier _OP3 is plotted on the vertical axis.) When the displacement signal is a reverse speed signal, a positive voltage is output at the point D. The photocoupler contact PCa of the inverter circuit, which will be described later, is closed via the optical signal emitted by the photocoupler PC.

The positive phase input terminal of the fourth operational amplifier OP ₄ is grounded via the first resistor R ₁ , and the output terminal E is connected to the inverter 30 . A _second
A resistor R ₂ is connected, the output of the above point B and the output of the point C are added, and the displacement signal input to the input terminal A is taken as the horizontal axis, and the output signal at the output terminal of the fourth operational amplifier OP ₄ is expressed as As shown in the graph of FIG. 6 plotted on the vertical axis, a V-shaped addition signal is output and input to the speed signal terminal of the inverter 30.

The above-mentioned inverter 30 is interposed in the power supply circuit in order to convert the power supply frequency of the above-mentioned tenter rail 1 sliding induction motor 40,
When a speed signal is input from the fourth operational amplifier OP ₄ to the speed signal terminal O, the power supply frequency of the induction motor 40 is changed to increase or decrease its speed, and the photocoupler contact PCa of the input terminal P for reverse rotation command performs the third calculation. When closed by the output of amplifier OP ₃ , the direction of rotation of induction motor 40 is reversed.

In the above structure, when the tenter rail 1 is within a predetermined swing range, the first limit switch
When LS ₁ and second limit switch LS ₂ are each closed, tenter rail 1 swings left and right following the edge of fabric F. However, when the limit of the swing range is reached and either the first limit switch LS ₁ or the second limit switch LS ₂ opens, the tracking on the open side stops, thereby preventing danger.

(Effect of the invention) This invention uses an induction motor to swing the tenter rail, and an inverter interposed in the power supply circuit of the induction motor receives a forward rotation speed signal and a reverse rotation speed signal based on the displacement of the edge of the fabric. input to change the power frequency, and when inputting the reverse speed signal, input the reverse command signal at the same time to perform phase conversion.
Since the induction motor is rotated forward or reverse and the speed is increased or decreased, the swinging speed can be increased or decreased depending on the displacement of the ear end, and the carbon fiber required when using a DC motor can be adjusted. This eliminates the need for brushes, and eliminates the need to replace carbon brushes due to poor contact or wear.

[Brief explanation of the drawing]

Figure 1 is a block diagram of an embodiment of this invention, Figure 2 is a block diagram of an embodiment of this invention.
The figure is a circuit diagram of the preamplifier, Figure 3 is a graph explaining the operation of the first operational amplifier OP ₁ , Figure 4 is a graph explaining the operation of the second operational amplifier OP ₂ , and Figure 5 is a graph explaining the operation of the second operational amplifier OP 2. A graph explaining the operation of the amplifier _OP3 , and FIG. 6 is a graph explaining the operation of the fourth operational amplifier _OP4 . DESCRIPTION OF SYMBOLS 1... tenter rail, 2... tenter chain, 10... edge feeler, 11... feeler bar, 20... preamplifier, 30... inverter, 40... induction motor.

Claims (1)

[Scope of utility model registration request] A selvage feeler is provided on the fabric inlet side of the tenter, and the selvage feeler is placed in contact with the selvage of the fabric just before it is held in the tenter chain, and outputs an electric signal of a magnitude corresponding to the displacement of the feeler bar. , receives the output signal of the edge feeler and outputs a forward rotation speed signal and a reverse rotation speed signal proportional to the positive direction displacement and negative direction displacement, respectively, with respect to the neutral point of the feeler bar, and also outputs a reverse rotation command signal when the reverse rotation speed signal is output. The speed signal terminal of the inverter for speed control is connected to a preamplifier that outputs the same, and the output terminals of the forward speed signal and reverse speed signal of this preamplifier are interposed in the power supply circuit of the induction motor for sliding the tenter rail on the entrance side. , and an output terminal for a reverse command signal of the preamplifier is connected to a reverse command input terminal of the inverter.