JPH0745143A - Method and apparatus for twisting litz wire - Google Patents

Abstract

PURPOSE:To accurately control the twisting pitch by improving a twisting method and twisting apparatus for twisting litz wires. CONSTITUTION:A bobbin 1 is rotated by a bobbin-driving mechanism 7 at a rotational speed Nb while, on the other hand, a flyer 3 is rotated by a flyer- driving mechanism 9 at a rotational speed Nf. An automatic control device 8 has inputted thereto from a rotary encoder 6 a signal that represents the travel speed V of a center wire element 4a, has inputted thereto from a non- contact sensor 10 a signal that represents the distance L to thereby calculate the winding diameter D and calculate the travel speed V. Further, the rotational speeds Nf and Nb are controlled so that the ratio between the travel speed V and the rotational-speed difference (Nf-Nb) may be kept constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for twisting a plurality of individually insulated wires to twist a litz wire, and an apparatus for carrying out the above method.

[0002]

2. Description of the Related Art A litz wire has a reduced skin effect and a reduced radio frequency resistance, and is formed by twisting and braiding individually insulated wires (hereinafter simply referred to as wires). To reduce the skin effect, each strand is sequentially braided to occupy all positions in the cross section of this strand. Therefore, the individual wires that make up the litz wire (hereinafter,
The number of strands) is 3, 7, 19 or more. FIG. 4 is a schematic drawing of the cross-sectional shape of various litz wires, and (A) is a cross-sectional view of a three-strand litz wire,
(B) is a sectional view of a 7-strand Litz wire, and (C) is a sectional view of a 19-strand Litz wire. The present invention can be applied to a litz wire having 19 strands or more. FIG. 3 is a view for explaining a method for twisting a litz wire according to a conventional technique, and is a perspective view schematically illustrating a litz wire twisting device, in which an arrow indicating a rotation direction is added. is there. Bobbin 1 is bobbin shaft 2
Supported by a rotary drive mechanism (not shown),
Rotation speed N around the center line ZZ as indicated by an arc arrow Nb
It is rotated at b (r.p.m.). On the other hand, the flyer 3 is supported by a rotary drive mechanism (not shown), and is concentric with the bobbin 1 around the center line ZZ as indicated by an arc arrow Nf, that is, in the same direction as the bobbin 1 with a rotation speed N.
It is rotated at f (r.p.m.). A large number of wires (strands, 7 in this example) 4a to 4g are supplied toward the inlet 3a of the flyer 3, and these wire strands are collectively sent out from the flyer outlet 3b. With the above configuration and operation, the seven wire strands 4a to 4g
Is twisted into a stranded wire 5 and wound on the bobbin 1.
The mechanism of the above twisting action will be described in more detail below. When the flyer 3 makes one rotation, the wire is twisted once. Therefore, assuming that the bobbin 1 is stationary, the flyer 3 is twisted once while the stranded wire 5 is wound around the bobbin 1 once by one rotation. Assuming that the winding diameter of the twisted wire 5 being wound around the bobbin 1 in the illustrated state is D, one rotation of the flyer 3 causes the twisted wire 5 having a length of πD.
Is wound around the bobbin 1, and the twisted wire is twisted once during this time. However, since the twist is too weak (the twist pitch is too long), the bobbin 1 is rotated in the same direction as the fry and 3 at a rotation speed lower than that of the flyer 3 to strengthen the twist (shorter the twist pitch). To do. Now, Nf = 5000r. P. m Nb = 4980r. p. Consider the state of m 2.

The speed difference between the flyer 3 and the bobbin 1 is Nf-
Nb = 5000-4980 (rpm) = 20r.
p. Since it is m, when considering one minute, the twisted wire 5 is wound around the twisted wire wound around the bobbin 1 and wound 20 times. Its length is πD × 20.

Since the flyer 3 rotates 5000 times in this 1 minute, the twisted wire 5 is twisted 5000 times.

Therefore, the twisted wire pitch (length / number of twists) is
It becomes (πD × 20) / 5000.

As is clear from the prior art relating to the above-mentioned twisted wire principle, the twisted wire pitch = πD (Nf-Nb) / Nf (1), the rotational speed Nf of the flyer 3 and the bobbin 1 The litz wire can be configured with an arbitrary twist pitch by appropriately selecting the rotation speed Nb.

[0007]

Among the four kinds of numerical values constituting the equation (1) for determining the twisted wire pitch according to the prior art, π is a constant and Nf and Nb can be easily controlled. However, the winding diameter D of the twisted wire is a variable and increases with the passage of time. For this reason, if Nf and Nb are kept constant and the twisted wire is twisted, the twisted wire pitch will gradually increase. In order to eliminate such problems, the rotation speed Nf of the flyer 3
A technique for controlling the rotation speed Nb of the bobbin 1 according to a precalculated position is well known, and is generally widely used. However, with technological advances in wireless engineering, electrical components have become extremely small and highly precise, and the demands on the litz wire for shape and dimensional accuracy have become extremely severe. Therefore, as in the prior art, it is necessary to ignore the subtle changes in many influential factors related to the winding work and simply control the rotation speed as calculated in advance to meet the demand (high accuracy) of the times. I can't cut it. The present invention has been made in view of the above circumstances, and provides a twisting method capable of significantly improving the accuracy of a twisted wire pitch, and a twisting apparatus suitable for carrying out the above twisting method. The purpose is to do.

[0008]

The basic principle of the present invention created in order to achieve the above-mentioned object will be summarized as follows. That is, considering the above-mentioned formula (1), the circular constant π is an invariable constant and the rotational speed Nf,
Nb can be controlled directly with relative ease. Therefore, the present invention detects the value of D in the equation (1) and controls the rotation speeds Nf and Nb based on this value. Further, considering with reference to FIG. 3 described above, the value of πD in the equation (1) is the length of one turn around which the twisted wire 5 is wound. The length of one round is the length of travel of the wire in terms of the time (cycle) required for the flyer to make one rotation, and the speed of travel of the wire in terms of unit time. Focusing on these points, measuring the winding diameter D and the traveling speed of the wire are the same in principle, and either method may be used. A first method according to the present invention as a concrete means based on the above-described principle is to supply a plurality of wires to the inlet side of a flyer and feed the plurality of wires from an outlet of the flyer while A bobbin that is rotated at a rotation speed Nf and that winds a plurality of wires fed from the exit of the flyer,
Rotation speed N such that Nb <Nf in the same direction as the flyer.
In the litz wire twisting method for twisting the plurality of wires by rotating at b, the traveling speed V of the wires is detected for at least one of the plurality of wires supplied to the flyer. , The differential speed Nf-Nb between the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin, and the flyer so as to keep the ratio between the differential speed Nf-Nb and the traveling speed V constant. It is characterized in that at least one of the rotation speed Nf and the rotation speed Nb of the bobbin is controlled.

The second invention method based on the above-mentioned principle is
In the same case as the first invention, the diameter dimension D of the uppermost layer of the twisted wire wound around the bobbin is detected in a non-contact manner, and based on the rotation speed Nb of the bobbin and the diameter D. Then, the linear velocity V'of the wound twisted wire is calculated, and the differential speed Nf-Nb between the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin is calculated to obtain the differential speed Nf- At least one of the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin is controlled so that the ratio between Nb and the linear velocity V'is kept constant.

In order to carry out the above-described method of the invention, the structure of the litz wire twisting device according to the present invention is a flyer for collectively feeding a plurality of supplied wires,
A litz wire having a flyer drive mechanism that supports and rotates the flyer, a bobbin that winds a wire sent from the flyer, and a bobbin drive mechanism that supports the bobbin and rotates concentrically with a rotation axis of the flyer. In the twisted wire device, the sensor that directly or indirectly detects the speed at which the wire passes through the flyer and the output signal of the sensor are input, and an operation command is given to the fly, the drive mechanism, and the bobbin drive mechanism. An automatic control device for controlling the operation of the wire is provided, and the automatic control device has a constant ratio between the speed difference of the rotation speed of the flyer and the rotation speed of the bobbin and the speed of the wire. As described above, the flyer drive mechanism and the bobbin drive mechanism are controlled. As the sensor for directly detecting the speed of the wire, for example, a rotary encoder having a pulley around which the wire is wound can be considered. Further, as a sensor that indirectly detects the speed of the wire, a non-contact sensor that measures the winding diameter of the twisted wire wound around the bobbin can be considered.

[0011]

[Operation] The twist pitch of the litz wire is the unit length of the twist wire /
Determined by the number of twists. Then, the number of twists exactly matches the number of rotations of the flyer. Therefore, the present invention is applied to detect the unit length of the stranded wire (the running speed of the wire when a time factor is added to this), and based on the detected value, the rotational speed difference between the flyer and the bobbin. The twist pitch can be accurately controlled by controlling the.

When the rotational speed is controlled according to the previously calculated value as in the prior art, various error factors are introduced. However, when the unit length of the stranded wire (running speed, winding diameter, and the technical significance are equivalent) is measured as in the present invention, the result of a complicated and influential influence of various error factors If the unit length per hour (wire traveling speed), which is a numerical value, is detected and the rotational speed difference between the flyer and the bobbin is controlled based on this detected value, no more errors will be mixed in. The twist pitch can be controlled accurately.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the method and apparatus of the present invention will be described with reference to FIG. 1 and FIG. FIG. 1 is a perspective view schematically showing a working state in one embodiment of a litz wire twisting method according to the present invention. This embodiment is an improvement of the conventional example shown in FIG. 3 by applying the present invention, and those denoted by the same reference numerals as those in FIG. . 4a to 4g are seven wire strands as a material for forming the twisted wire 5, and among them, 4a is a central wire strand. However, when implementing the present invention, there is no particular restriction on the number of wire strands. This example is intended to form the 7-strand litz wire shown in FIG. 4 (B), and one of the 7 litz wires 4a to 4g should be located at the center. Lines (shown with spots) 4a are present. When viewed as a material before twisted wire processing, the seven litz wires 4a to 4g are members similar to each other, and one of them is twisted while guiding so as to be located at the center. In the 19-strand litz wire shown in FIG. 4 (C), the wire strand of 4k in the drawing (shown with spots) is the central wire strand. 3 shown in FIG.
3 wire strands 4h to 4j in the main twisted litz wire
Are equal to each other, and there is no distinction between the central wire strand and the non-central wire strand. In FIG. 1, 4a is a wire strand that is guided as centrally as possible. In this embodiment, the rotary encoder 6 detects the traveling speed V of the center wire 4a. Although not shown in the drawings, as an embodiment different from this, it is possible to detect the traveling speed other than the center wire strand. Then, the rotational speed Nb of the bobbin 1 is controlled while keeping the rotational speed Nf of the flyer 3 constant, and the ratio between the rotational speed difference (Nf-Nb) between the flyer 3 and the bobbin 1 and the traveling speed V is kept constant. keep. Thereby, regardless of the change in the winding diameter D of the twisted wire wound around the bobbin 1, the twisted wire is performed at a constant twist pitch, and high accuracy is obtained. Figure 2
Is a schematic perspective view showing one embodiment of a litz wire twisted wire device according to the present invention configured to carry out the above-mentioned invention method,
It is the figure which added the drive mechanism, the sensor, and the control system. Reference numeral 7 denotes a bobbin drive mechanism, which supports the bobbin 1 via the bobbin shaft 2 and moves the bobbin 1 in a circular arc arrow N according to an operation command given from the automatic control device 8.
In the b direction, the rotation speed Nbr. p. Rotate at m. Reference numeral 9 denotes a flyer driving mechanism, which supports the flyer 3 and is concentric with the rotation axis ZZ of the bobbin 1 and has a circular arc arrow Nf.
In the same direction as the bobbin 1 in accordance with the operation command of the automatic control device 8, the rotation speed Nfr. p. Rotate at m.
The rotary encoder 6 has a wire wire 4 to be the center.
The rotation speed of the pulley 1 around which a is wound is detected, and a detection signal is sent to the automatic control device 8. The automatic control device 8 calculates the traveling speed V of the central wire 4a based on the output signal of the rotary encoder 6, and determines the differential speed (Nf-Nb) between the rotational speed Nf of the flyer 3 and the rotational speed Nb of the bobbin 1. )
The rotation speed is controlled so as to be proportional to the speed V.

The wire running speed is detected by the rotary encoder 6 for the center wire element wire 4k in the case of twisting 19 strands as shown in FIG. 4 (C). Further, even in a litz wire composed of a larger number of wire strands, each has a center wire strand, so that the wire strand guided to become the center wire strand is wound around the pulley of the rotary encoder. In the case of twisting a three-strand litz wire as shown in FIG. 4 (A), since there is no distinction between the center wire element wire and the non-center wire element wire, three wire element wires 4
It suffices to wind any one of h to 4j around the pulley to detect the traveling speed V.

As an embodiment different from the above, a non-contact type distance sensor 10 is installed to detect the distance L to the outer circumference of the winding diameter of the twisted wire 5 being wound around the bobbin 1, and the output signal is automatically controlled. Input to the device 8. The automatic control device 8
Calculates the winding diameter D of the twisted wire 5 based on the distance L and calculates the traveling speed V of the wire from the value D and the rotation speed Nb, and controls the rotation speed in the same manner as in the above embodiment. To do. The non-contact type distance sensor is used in the present embodiment because the contact type sensor cannot be used because it may interfere with the flyer 3.

[0016]

The twist pitch of the litz wire is determined by the unit length of the twisted wire / the number of twists. Then, the number of twists exactly matches the number of rotations of the flyer. Therefore,
The present invention is applied to detect the unit length of a stranded wire (the wire running speed when a time factor is added to the stranded wire) is detected, and the rotational speed difference between the flyer and the bobbin is controlled based on the detected value. By doing so, the twist pitch can be accurately controlled.

When the rotational speed control is performed according to the previously calculated value as in the prior art, various error factors are introduced. However, when the unit length of the stranded wire (running speed, winding diameter, and the technical significance are equivalent) is measured as in the present invention, the result of a complicated and influential influence of various error factors If the unit length per hour (wire traveling speed), which is a numerical value, is detected and the rotational speed difference between the flyer and the bobbin is controlled based on this detected value, no more errors will be mixed in. It has an excellent practical effect that the twist pitch can be accurately controlled.

[Brief description of drawings]

FIG. 1 is a perspective view schematically illustrating a working state in one embodiment of a litz wire twisting method according to the present invention.

FIG. 2 is a schematic perspective view showing one embodiment of a litz wire twisted wire device according to the present invention configured to carry out the above-mentioned method of the present invention, in which a drive mechanism, a sensor, and a control system are added. .

FIG. 3 is a view for explaining a method for twisting a litz wire according to a conventional technique, and is a perspective view schematically showing a twisting device for a litz wire, in which an arrow indicating a rotation direction is added. Is.

FIG. 4 is a schematic drawing of the cross-sectional shape of various litz wires, in which (A) is a cross-sectional view of a three-strand litz wire, and (B).
Is a cross-sectional view of a 7-strand litz wire, and (C) is a cross-sectional view of a 19-strand litz wire.

[Explanation of symbols]

1 ... Bobbin, 2 ... Bobbin shaft, 3 ... Flyer, 3a ... Flyer inlet, 3b ... Flyer outlet, 4a ... Central wire strand, 4b-4j ... Wire strand, 4k ... Central wire strand,
5 ... Stranded wire, 6 ... Rotary encoder, 7 ... Bobbin drive mechanism, 8 ... Automatic control device, 9 ... Flyer drive mechanism, 10 ...
Non-contact type distance sensor, D ... Winding diameter of stranded wire wound on bobbin, L ... Detection distance of non-contact distance sensor, Nb ... Rotation direction and rotation speed of bobbin, Nf ... Rotation direction and rotation speed of flyer, V: Wire traveling speed.

Claims (5)

[Claims] 1. A plurality of wires are supplied to an inlet side of a flyer, and while the plurality of wires are paid out from an outlet of the flyer, the flyer is rotated at a rotation speed Nf, and from the outlet of the flyer. A bobbin that winds a plurality of wires that are fed out, in the same direction as the flyer,
A litz wire twisting method for twisting a plurality of wires by rotating at a rotation speed Nb such that Nb <Nf, wherein at least one of the plurality of wires supplied to the flyer has a speed of the wire. The traveling speed V is detected, the differential speed Nf-Nb between the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin is calculated, and the ratio between the differential speed Nf-Nb and the traveling speed V is made constant. A litz wire twisting method, characterized in that at least one of the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin is controlled so as to keep it. 2. A plurality of wires are supplied to the inlet side of the flyer, and while the plurality of wires are fed from the outlet of the flyer, the flyer is rotated at a rotation speed Nf, and from the outlet of the flyer. A bobbin that winds a plurality of wires that are fed out, in the same direction as the flyer,
In the litz wire twisting method of twisting the plurality of wires by rotating at a rotation speed Nb such that Nb <Nf, the diameter dimension D of the uppermost layer of the twisted wire wound around the bobbin is not contacted. And the linear velocity V'of the wound and twisted wire is calculated based on the bobbin rotational speed Nb and the diameter D, and the flyer rotational speed Nf and the bobbin rotational speed are calculated. The differential speed Nf-Nb with Nb is calculated, and the rotational speed Nf of the flyer and the rotational speed Nb of the bobbin are controlled so that the ratio between the differential speed Nf-Nb and the linear speed V'is kept constant. A method for twisting a litz wire, which comprises controlling at least one of them. 3. A flyer that collectively feeds a plurality of supplied wires, a flyer drive mechanism that supports and rotates the flyer, a bobbin that winds the wire that is fed from the flyer, and a bobbin that supports the bobbin. A litz wire twisting device having a bobbin drive mechanism that rotates concentrically with the rotation axis of the flyer, a sensor that directly or indirectly detects the speed at which the wire passes through the flyer, and an output signal of the sensor. And an automatic control device for giving an operation command to the fly, the drive mechanism, and the bobbin drive mechanism to control the operation thereof,
And, the automatic control device controls the flyer drive mechanism and the bobbin drive mechanism so that the ratio of the speed difference between the rotation speed of the flyer and the rotation speed of the bobbin and the speed of the wire becomes constant. A twisting device for litz wire, which is characterized in that 4. The sensor for detecting the speed of the wire is a tachometer having a pulley around which at least one of the plurality of wires supplied to the flyer is wound. The litz wire twisting device according to claim 3. 5. The sensor for detecting the speed of the wire is a distance meter for non-contactly detecting the distance to the wire wound on the bobbin, and the automatic control device is the above-mentioned. The litz wire twisting device according to claim 3, which has a function of calculating the speed of the wire wound around the bobbin based on the detection signal of the range finder.