JPH0368746B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a roller contact type applicator for applying a liquid such as wax or a solvent, and particularly to control of the rotational speed of the applicator roller.

Conventionally, the rotation control of the rollers of this type of device involves a method in which a mechanical drive shaft and the rollers are connected via a reducer and a change gear, and the rollers are rotated in proportion to the machine speed, that is, the yarn speed. Alternatively, a single motor is connected to the roller and the roller is operated at a constant rotation rate regardless of the speed of the machine.

In the former control method, when changing the amount of wax etc. applied, the change is always in stages,
In addition, it is necessary to replace the chain gear, which is a time-consuming process, and in particular, when trying to achieve stepless control, a large number of gears are required, and the most appropriate gear is selected from among them using numerical tables. Requires complicated operations.

In the latter control method, although the control itself is stepless, the speed of the machine, that is, the speed of the yarn, and the rotational speed of the rollers are not related, so when trying to obtain a constant amount of yarn, the Depending on the change in speed, the rotational control of the individual motor must also be changed each time. This means that the applied amount is not constant, especially during acceleration or deceleration.

Furthermore, both have the following drawbacks. In other words, the rotation speed of the rollers in this type of device is
Normally, the yarn speed is very low, 1 rpm or less, even when operating at high speed, for example 200 m/min, and depending on the viscosity of the wax solution, the wax solution scooped up from the roller surface is transferred to the roller by the action of gravity. receives a downward force on the surface of As the rotation of the roller becomes even more extreme, the amount of wax solution reaching the top of the roller tends to decrease. Especially for yarn processing etc., the machine can be operated at low speed e.g.
When operating at 10 m/min, the number of rotations of the roller is 0.1 rpm or less, and this tendency becomes noticeable.

The present invention improves these drawbacks and makes it possible to easily and steplessly change the amount of wax solution etc. attached to the yarn, and to maintain the amount of wax applied at a constant value even if the yarn speed is changed. It is to do so.

Of the two conventional methods, the present invention belongs to the latter, that is, the single motor drive method. That is, in the control method of the present invention, a variable speed motor whose rotational speed can be controlled is connected directly or via a reducer to a roller that applies liquid such as wax, and the rotational speed of this variable speed motor is adjusted to the speed of the yarn sheet. component proportional to and a predetermined value (constant value)
The feature is that the control is performed in proportion to the sum signal obtained by adding . The rotational speed of the roller, that is, the variable speed motor, has a large proportion of the above-mentioned constant value in the region where the speed of the thread sheet is low, and an appropriate rotational speed is obtained, which compensates for the decrease in the amount of wax scooped up to the upper part of the roller. , In addition, in a region where the speed of the yarn sheet is high, the ratio of the above constant value is small and is approximately proportional to the speed of the yarn sheet. Here, the above-mentioned predetermined value, that is, the constant value, is determined in relation to the surface speed of the roller and the static falling speed of the works solution, etc. on the roller surface. The present invention is also characterized in that it provides an effective method for setting this value. In this way, even if the thread speed changes, the amount of wax solution lifted to the top of the roller can be set to be approximately constant.
The relationship between the thread speed and roller rotation speed will be described in detail later with reference to FIG. 2, but y=ax+b
It is expressed by the graphical formula of

On the other hand, the application of the wax solution requires that the thread sheet be attached to the position where it contacts the surface of the roller, that is, the upper surface of the roller. However, when the wax solution is supplied for the first time or after the roller is stopped for a long time, the wax solution on the surface of the roller descends due to gravity, and almost no wax solution adheres to the roller. Therefore, before starting work, it is necessary to rotate the roller at least half a turn to apply the wax solution to the surface of the roller.

For this reason, conventional devices have a structure in which a mechanical clutch is provided between the roller and a speed reducer, etc., and the drive section is once disconnected from the roller, and the roller is manually rotated.

The present invention enables the variable speed motor to be started and stopped by a push button or a switch while the thread is not running, to encourage the rotation of the rollers and to quickly prepare for work. A timer is used to automatically rotate the rollers about half a turn when the machine is started after being stopped for a long time, so that preparations are completed without excessive wax adhering to the rollers.

Hereinafter, the structure and operation of the present invention will be specifically explained based on an embodiment shown in the drawings.

First, FIG. 1 shows an outline of the control thread. The thread sheet 1 is traveling at a constant speed, comes into contact with the upper surface of the coating roller 2 on the way, passes through the guide roll 7, and is wound around the beam 14. The roller 2 is cylindrical and in a horizontal state,
Its lower surface is in contact with a liquid such as a wax solution 3, and is connected to a variable speed motor 5 via a speed reducer 4. On the other hand, a tachometer generator 8 is connected to the guide roll 7, and its output signal A is applied to one end of one voltage dividing variable resistor 9. Therefore, this output signal A becomes an output signal B by an arbitrarily changeable proportionality constant of the variable resistor 9, and is outputted to the summing point 15. The other variable resistor 10 is grounded at one end and receives a constant voltage V at the other end, and its movable end is connected to the summing point 15 to provide an output signal C. In this way, an output signal B proportional to the speed of the yarn sheet 1 and an output signal C of a predetermined value are added to the addition point 15.
is applied, becomes a sum signal, and is sent to the next summing point 16 via the contactor 11. Here, the contactor 11 is closed only while the yarn sheet 1 is running. The sum signal D is therefore sent as a speed command signal to the control amplifier 6 of the variable speed motor 5 via the summing point 16 only during the running of the yarn sheet 1.

On the other hand, a tachometer generator 12 is connected to the variable speed motor 5, and its output signal E is
This signal is negatively fed back to the summing point 16 on the input side of the control amplifier 6, and acts as a feedback signal for the variable speed motor 5. In this way, the rotational speed of the variable speed motor 5 is controlled by the speed command signal, that is, the sum signal D.
is controlled to the target speed value in proportion to. Note that the contactor 11 is opened and closed by detecting the voltage level of the output signal A. Further, the output signal A may not be detected from the tachometer generator 8, but may be a voltage for commanding the speed of the yarn, for example, a command voltage of a motor for driving the yarn sheet.

Since the control system is as described above, the rotational speed Va of the roller 2 can be calculated from the general graph formula y=ax+b as shown in FIG. It becomes Vb+b. Here too,
When the contactor 11 is always closed, the rotational speed Va of the roller 2 changes along the straight line b-a, but
When the yarn speed Vb is 0 and the roller 2 rotates,
Since this is inconvenient, when the yarn speed Vb becomes almost 0, the contactor 11 cuts off the input of the sum signal D and stops the rotation of the roller 2. As a result, the rotational speed Va of the roller 2 is set so as to follow the order of straight line 0-ba in the graph of FIG.

In the graph of FIG. 2, changing the coefficient of the variable resistor 9 corresponds to changing the slope of the straight line a-b, that is, the coefficient K of the above equation, and changing the coefficient of the variable resistor 10. is the straight line 0-b
This corresponds to adjusting the length of C, that is, the level of the output signal C.

Next, FIG. 3 shows the relationship between the yarn speed Vb and the rotational speed Va of the roller 2 on the time axis t. now,
As will be described in detail later, after adjusting the variable resistor 10 in relation to the falling speed of the wax solvent, by adjusting the amount of wax solvent 3 applied to the yarn using the variable resistor 9, the yarn speed Vb can be adjusted. In addition to changes,
You can receive a constant amount even when accelerating or decelerating. Furthermore, in speed control of the variable speed motor 5, in the conventional control method, comparison control may not be maintained in the low rotation range, but with the control method of the present invention, such characteristics can be corrected.

Furthermore, if the push button switch 13 is turned on after the machine has been stopped for a long time and before starting operation, the constant voltage V becomes the speed command signal for the control amplifier 6, and the roller 2 rotates, causing the surface of the roller 2 to The wax solution 3 will adhere and the preparation work can be done easily.
Replacing the push button switch 13 with a timer that operates for a certain period of time when the push button switch 13 is started after being stopped for a long time,
It is advantageous that the preparatory work can be carried out automatically if the roller 2 is rotated approximately half a turn. In addition, at the addition points 15 and 16, the plus sign indicates the electrical polarity for rotating the variable speed motor 5 in the forward direction, and the minus sign indicates the polarity for rotating the variable speed motor 5 in the reverse direction.

Here, the relationship between the rotational speed Va of the roller 2 and the amount of adhered viscous fluid such as the wax solution 3 will be analyzed with reference to FIGS. 4 and 5. A viscous fluid such as the wax solution 3 has a falling speed of 0 in the part where it is in contact with the surface of the roller 2, and
It is thought that as the object moves away from the surface in a direction perpendicular to the tangent, it falls due to gravity with a certain velocity gradient related to viscosity. From this theory, it is assumed that the falling speed Vc of the wax solution 3 on the surface increases in proportion to the distance from the surface of the roller 2.

Now, in FIGS. 4 and 5, regarding the part P of the wax solution 3 in the tank that is not affected by surface tension, the amount of wax solution 3 that is lifted by the rotation of the roller 2 and falls due to gravity. Consider the amount of trend wax solution 3. This 2
By determining the difference between the two amounts, the amount Q of the wax 3 that adheres to the surface of the roller 2 and is continuously lifted as the roller rotates can be determined. The initial amount of wax solution 3 lifted by roller 2, that is, the thickness W in the direction perpendicular to the tangent to the surface of roller 2, is approximately equal to It is considered to be constant.

On the other hand, when a wax solution with a thickness of W is applied to the surface of the roller 2 and the roller 2 is kept stationary, if the static falling speed at the outer circumference of point P is Vc, this static falling speed Vc is the same as the roller 2 rotating. It is considered to be approximately constant regardless of the rotational speed Va of the roller 2. On the other hand, since the static falling speed or relative speed of the part where the wax solution 3 is in contact with the surface of the roller 2 is considered to be 0, the average falling speed or average relative speed of the wax solution 3 with respect to the thickness W is Vc/2. . The amount Q of wax solution that adheres to the roller 2 per unit time corresponds to the value obtained by subtracting the falling amount (shaded area in Figure 5) from the initial waiting amount, so it can be expressed by the following formula ( 1) holds true.

Q=Va×W×L-1/2Vc×W×L ……(1) Here, L is the length of the roller 2.

Now, since the purpose of the control of this invention is to make the amount Q of the wax solution 3 proportional to the yarn speed Vb, the relationship can be expressed by the following equation (2) using the proportionality constant k.
It is expressed as follows.

Q=k×Vb×W×L...(2) In order to obtain the relationship of formula (2) above, formula (1) and formula
Equation 3 below can be obtained from (2).

k×Vb=Va−1/2Vc Va=k×Vb+1/2Vc ……(3) From the above equation, the amount Q of wax solution 3 and yarn speed Vb
becomes proportional if the rotation speed Va on the surface of the roller 2 is set to a constant speed corresponding to Vc/2 plus a speed proportional to the yarn speed Vb.

In FIG. 4, the solid line indicates Va≫Vb/2, and the dotted line indicates Va≈Vc/2.

The output signal C is set by rotating the roller 2 at high speed, then stopping it, and measuring the static falling velocity Vc of the wax solution 3 on the outer periphery of point P. This is done by adjusting the level (predetermined value) corresponding to the speed Va using the variable resistor 10.

In the present invention, the rotation of the roller for contact application is performed steplessly in proportion to a constant value + yarn speed.
This eliminates the need for change gears, which makes operation easier, and prevents sticking spots during acceleration and deceleration, as well as sticking spots at low speeds. Therefore, the amount of liquid applied to the yarn sheet can be controlled with high precision.

[Brief explanation of drawings]

Fig. 1 is a system diagram of the control method of the present invention, Fig. 2 is a graph of roller rotation speed vs. yarn speed, Fig. 3 is a graph of the relationship between roller rotation speed and yarn speed and time, and Fig. 4 is a graph of the relationship between roller rotation speed and yarn speed. An explanatory diagram showing the relationship with the amount of liquid agent adhered, FIG. 5 is an enlarged model diagram at point P in FIG. 4. 1... Thread sheet, 2... Roller, 3... Wax solution, 4... Speed reducer, 5... Variable speed motor, 6
... Control amplifier, 7 ... Guide roll, 8 ... Tachometer generator, 9, 10 ... Variable resistor, 11
...Contactor, 12...Tachogenerator, 13...
...Push cap switch, 14...Beam, 15,1
6...Additional points.

Claims (1)

[Scope of Claims] 1. For driving the roller in a roller contact type liquid application device that applies the liquid to yarn by bringing a yarn sheet into contact with the surface of a coating roller that rotates in the liquid. A method for controlling a motor for a roller contact type liquid agent application device, characterized in that the rotational speed of the variable speed motor is controlled by comparing it with a sum signal obtained by adding a signal proportional to the speed of the yarn sheet and a signal of a predetermined value. 2. Claim 1, characterized in that the proportionality constant of the signal proportional to the speed of the yarn sheet and the signal value of the predetermined value can be arbitrarily varied.
A method for controlling a motor of a roller contact type liquid dispensing device as described in 1. 3. Claim 1 or 2, characterized in that when the roller is operated after being stopped for a long time, the roller automatically rotates at high speed for about half a turn or more and then enters a normal operating state. A motor control method for a roller contact type liquid dispensing device. 4. The roller contact type liquid agent according to claim 1, 2, or 3, wherein the predetermined value is set in relation to the rotational speed of the roller and the falling speed of the liquid agent on the roller surface. A motor control method for an applicator.