JP3527870B2 - Brake equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention controls tension in a device for winding a slender object such as a thread, tape, or electric wire.
The present invention relates to a brake device used in a tension control device that can accurately measure a winding length and a yarn amount, and particularly relates to a braking force that can be controlled by a current command value and a rotational speed of a rotating shaft. The present invention relates to a high-accuracy, low-power-consumption braking device having a structure capable of exerting a constant braking force.

[0002]

2. Description of the Related Art FIG. 5 shows a conventional thread,
FIG. 3 is a schematic view showing an example of the installation state of a brake device used for a winding device for a tape, an electric wire, etc., in which 100 is a yarn to be wound, 101 and 105 are guide rollers, 103 is a brake roller, 104 is a brake, and 106. Is a winding core metal, 1
Reference numeral 07 is a winding motor.

In the brake device shown in FIG. 5, a yarn 100 to be wound is wound around a brake roller 103 through a guide roller 101, and a winding motor 107 is wound by a winding core metal 106 through a guide roller 105. The structure is such that the brake 104 applies a predetermined tension to the yarn.

There are various types of conventional braking devices used in a winding device for winding thread, tape, electric wire, etc., as shown in FIG. 5, and the features and problems thereof are listed below. Become.

(1) A general-purpose hysteresis brake is used, which has a structure in which a rotor formed of a magnetic material having hysteresis and a stator having a plurality of windings face each other. The wire is energized to generate a multi-pole magnetic flux, and the braking force is generated by the hysteresis loss generated in the rotor having the hysteresis characteristic, so that electric power to be supplied to a plurality of windings is required.

(2) In a structure in which a rotor made of a magnetic material having a large hysteresis coefficient and a multi-pole magnetized magnet are arranged so as to face each other with an air gap therebetween. The braking force is generated by the hysteresis loss generated between the magnetic flux and the rotor with a large hysteresis coefficient. Since there is no winding and no power loss occurs, the braking force is controlled by changing the distance between the magnet and the hysteresis member. Therefore, it cannot be controlled to be variable by an electric signal. There is also a problem that when the rotation speed of the brake changes, the hysteresis loss changes and the braking force changes.

(3) It has the same structure as a DC motor in which a rotor provided with a multi-pole magnetized magnet and a stator provided with an iron core having a plurality of windings face each other. A structure having a structure in which a braking force is generated by energizing a plurality of windings of a stator having an iron core to generate a multi-pole magnetic pole, and an electromagnetic force generated between the rotor and a magnetic flux of a rotor magnet via an air gap, Electric power is required for energization, and when the rotational speed changes due to the hysteresis loss of the iron core, the braking force changes.

(4) With the structure in which the above motor is used as a generator, an induced voltage is generated in the winding due to the rotation of the rotor, and an energizing circuit is connected to the winding to cause a regenerative current to flow. The braking force is controlled by controlling the current, and there is a problem that the braking force changes when the rotation speed changes due to the hysteresis loss of the iron core.

[0009]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention (1) to (4)
In various prior arts shown in (a), since a large number of braking devices are used in the winding device for (a) yarn and the like, a large amount of electric power is required to generate the braking force.

(B) In the yarn winding device, when the diameter of the winding bobbin increases with the winding amount, the yarn speed increases, and when the winding speed is changed to control the yarn speed, Since the rotation speed of the brake changes and the braking force changes, it is necessary to make a correction in the control circuit or the like.

(C) The brake force cannot be continuously varied.

(D) The yarn length cannot be accurately measured due to the change in the outer diameter of the winding bobbin. There was such a problem.

An object of the present invention is to control a tension of a device for winding a slender object such as a yarn, a tape and an electric wire, and to use it for a tension control device capable of measuring a winding length and a yarn amount. It is to provide a brake device with high accuracy and low power consumption.

[0014]

In order to achieve the above-mentioned object of the present invention, a structure as set forth in the claims is adopted. That is, as described in claim 1,
A braking device having a structure in which a braking force acts on the rotating shaft when the rotating shaft is rotated from the outside, and the braking device has N in the circumferential direction.
A magnet having poles and S poles alternately magnetized and a yoke made of a magnetic material are fixed to the rotary shaft via a gap,
A coreless stator winding was disposed in the air gap, and a terminal of the stator winding was connected to a current control device capable of controlling a predetermined current value to rotate the rotary shaft from the outside. At this time, a current flows through the current control device due to an induced voltage generated in the stator winding, and a braking force acts on the rotating shaft.

Further, as described in claim 2, claim 1
In the brake device described in the paragraph (1), the magnet is formed in a disc shape, and an N pole and an S pole are alternately magnetized in a circumferential direction on an end surface of the magnet, and the yoke is made of a magnetic disc. The coreless stator winding is a braking device having a structure arranged on a plane substantially perpendicular to the rotation axis.

Further, as described in claim 3, claim 1
In the brake device described in the paragraph (1), the magnet is formed in a cylindrical shape, and N poles and S poles are alternately magnetized in a circumferential direction on an inner peripheral surface thereof, and the yoke is formed of a magnetic cylinder. The coreless stator winding is a brake device having a cylindrical structure that is substantially parallel to the rotation axis.

Further, as described in claim 4, claim 2
In the brake device described in the paragraph (1), a rotor integrally fixed to a rotor boss is fixed to the rotary shaft, and a magnet having N and S poles alternately magnetized in a circumferential direction is fixed to an end surface of the rotor. A brake device having a structure in which a preset number of through holes in the axial direction are provided in a yoke formed of the rotor boss and a magnetic material.

Further, as described in claim 5, claim 1
The braking device according to any one of claims 1 to 4, wherein the current control device connected to the stator winding is:
The brake device has a control circuit that controls a current of a stator winding to a predetermined current value by commanding a current command value with a pulse width modulation (PWM) signal.

Further, as described in claim 6, claim 1
The brake device according to claim 5, wherein the current control device is a current control device in which a circuit for converting a current value command signal based on a PWM signal into a voltage and a power transistor and a current detection resistor are connected in series. And a DC voltage output obtained by converting the output of the stator winding of the brake device by a full-wave rectification circuit, and connecting the circuit to the current control circuit.
A braking device having a control circuit for controlling the current of the stator winding to match the current value command signal.

Further, as described in claim 7, claim 1
The brake device according to any one of claims 1 to 6, wherein the brake device includes a converter that converts an output voltage of the stator winding into a pulse voltage proportional to a frequency of the output voltage. is there.

[0021] Further, as described in claim 8, claim 1
The brake device according to any one of claims 1 to 7, wherein the coreless stator winding is a brake device in which three-phase windings are star-connected.

According to the present invention, as described in claims 1 to 8, when a rotating shaft is rotated from the outside, a braking force acts on the rotating shaft, which is NS alternating in the circumferential direction. A magnet magnetized to the magnet and a yoke made of a magnetic material through the magnet and a gap, and fixed to the rotary shaft,
A coreless stator winding is arranged in the gap between the yoke and the magnet, and a current control device capable of controlling a predetermined current is connected between the terminals of the stator winding to rotate the rotary shaft from the outside. At this time, an induced voltage generated in the stator winding causes a current to flow through the current control device, so that a braking force acts on the rotating shaft.

With this structure, the rotating shaft, the magnet, and the yoke are integrally rotated, and the stator is provided with a coreless winding without an iron core. Since there is no loss due to the hysteresis of the iron part of the magnetic circuit due to the rotation of the rotating shaft, there is no change in the braking force due to the rotation speed, and there is little power consumption, which is an excellent feature that was not obtained with the conventional technology. This is a braking device having an effect.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> FIG. 1 is a sectional view showing the structure of a brake device exemplified in the first embodiment.
It has substantially the same structure as an axial gap type brushless motor, 1 is a rotary shaft, 2 is a roller fixed to the rotary shaft 1, 3 is a bracket which is a base of a brake device, and 4 is the rotary shaft which is rotatable. Bearing 5 to hold, 5 to rotor
a is a rotor boss, 5b is a through hole of the rotor boss provided in the rotor boss, 6 is a magnet, 7 is a yoke, 7b is a through hole of the yoke, 8 is a gap between the magnet 6 and the yoke 7, 9 is an insulating wiring substrate, Reference numeral 10 is a stator winding, and 11 is a current controller provided on the insulating wiring board.

The structure shown in FIG. 1 has a base bracket 3
A roller 2 is fixed to one end of a rotary shaft 1 rotatably supported by a bearing 4 provided on the rotor 5, and a rotor 5 integrated with a rotor boss 5a and a magnet 6 fixed to the rotor 5 are attached to the other end. A yoke 7 is fixed to the magnet 6 via a gap 8 and an insulating wiring board 9 and a stator winding 10 provided on the insulating wiring board 9 are arranged in the gap 8. The insulated wiring board 9 is equipped with a current control device 11 for supplying a predetermined current to the stator winding 10.

The rotor boss 5a of the rotor 5 is provided with a rotor boss through hole 5b in the axial direction, and the yoke 7 is provided with a yoke through hole 7b in the axial direction. The flow of air indicated by the arrow generated by the rotation of 7 reduces the pressure in the gap, and the through hole 5b of the rotor boss in the axial direction of the rotor and the through hole 7 of the axial yoke provided in the yoke 7 are formed.
A flow of air for cooling the stator winding 10 is generated via b.

In the braking device of the present invention shown in FIG. 1 in the first embodiment, when the roller 2 fixed to the rotary shaft 1 is externally rotated, the magnetic flux of the magnet 6 and the stator winding 10 act. An induced voltage having a frequency proportional to the rotation speed of the roller 2 is generated in the stator winding 10, and a current flows through the current control device 11 shown in FIG. 1, and the magnetic flux generated in the stator winding 10 by this current. And the magnetic flux of the magnet 6 act to generate an electromagnetic force on the magnet 6 and a braking force on the roller 2.

The braking force generated at this time is that the magnitude of the induced voltage generated in the stator winding 10 is proportional to the rotation speed of the roller 2, and the impedance of the energizing circuit by the current controller 11 is constant. If so, the current flowing through the stator winding 10 is proportional to the rotation speed, and the braking force is proportional to the rotation speed of the roller 2.

The magnet 6 integrated with the rotor 5
And the yoke 7 are fixed to the rotary shaft 1 and integrally rotate, so that there is no change in the magnetic flux passing through the yoke 7, so that no hysteresis loss occurs in the yoke 7 and the stator has an iron core. Since it has a coreless structure, there is no hysteresis loss due to the iron core even in the stator, and there is no change in the braking force due to the iron core, so there is no need to correct the braking force due to changes in rotational speed.

Therefore, in order to control the braking force to a constant value regardless of the change in the rotation speed of the rotor 2, the control command of the current control device 11 is set to the current flowing through the stator winding 10 regardless of the rotation speed. It suffices to control so that is constant.

FIG. 2 is a circuit diagram showing the configuration of the current control device 11 used in the brake device according to the present invention. The three-terminal outputs of the stator windings 10 of the six motors are composed of six diodes. The DC output of the full-wave rectifier 21, the + side terminal of the DC output of the full-wave rectifier 21 is connected to the collector of the power transistor 22, and the emitter of the power transistor 22 and the current detection resistor 23 are connected in series. Connect to the negative terminal of.

On the other hand, the input terminal Vcc of the power supply used for the controller and the PWM (pulse width modulation) for inputting the current command value
A transistor 24 of the DC voltage conversion circuit, which has a control terminal, a GND (ground) terminal, and a rotation pulse output terminal;
A first operational amplifier 25, and a PWM control terminal is connected to the base of the transistor 24 of the DC voltage conversion circuit by a resistor 2
6, the collector of the transistor 24 is connected to Vcc via the resistor 27, the emitter is connected to GND, and the collector is connected to the parallel circuit of the resistor 29 and the capacitor 30 via the resistor 28. , The upper end of the parallel circuit is connected to the + side input terminal of the first operational amplifier 25, the lower end is connected to GND, the-side terminal of the first operational amplifier 25 is connected to the emitter of the power transistor 22, The output of the operational amplifier 25 is the power transistor 2
It is connected to two bases.

Also, one terminal of the full-wave rectifier 21 on the AC side is connected to the minus terminal of the second operational amplifier 34, and two resistors 32 and 33 are connected to Vcc and the GND tube. It is connected to the + side terminal of the second operational amplifier 34, and the output of the second operational amplifier 34 is connected to the rotation pulse output terminal.

The operation of the current control device 11 shown in FIG.
An input voltage obtained by modulating a current command value with a PWM signal is input to the WM control terminal, demodulated by the transistor 24 of the DC voltage conversion circuit, and converted into a DC voltage proportional to the modulation duty by the parallel circuit of the resistor 29 and the capacitor 30, The voltage of the current detection resistor 23 is constantly input to the + side terminal of the first operational amplifier 25 and compared with the emitter voltage of the power transistor 21 (voltage of the current detection resistor 23) input to the − side terminal. Is controlled so as to coincide with the DC voltage proportional to.

By operating in this way, the roller 2
The current is controlled so that the voltage of the current detection resistor 23 matches the voltage proportional to the current command value even if the rotation speed of the stator winding changes and the induced voltage of the stator winding 10 changes. The current of 10 becomes constant and the braking force is kept constant.

The pulse signal generating circuit for detecting the rotational speed is a circuit for obtaining a pulse signal having a frequency proportional to the rotational speed of the rotor from the AC voltage of the induced voltage of the stator winding 10, The reference voltage obtained by dividing the power supply voltage Vcc input to the + terminal of the operational amplifier 34 circuit by the resistors 32 and 33 is compared with the AC voltage input to the − terminal, and the amplitude of the AC voltage exceeds the reference voltage. The pulse voltage that is sometimes output to the output terminal is output from the rotating pulse terminal as a pulse signal having a frequency proportional to the rotation speed of the rotor.

A conversion device for detecting the rotation speed from the interval of the pulse signals is provided, and the product length of the output of the conversion device and the diameter of the roller 2 can be used to accurately detect the yarn feed length (yarn amount). .

<Embodiment 2> In the brake device illustrated in Embodiment 2, the rotor magnet is of a cylindrical type, and a cylindrical yoke is provided on the inner peripheral surface of the rotor through a gap. The structure is almost the same as that of the radial gap type coreless motor in which the cylindrical coreless stator winding is arranged in the void of FIG. 3, and FIG. 3 is a sectional view showing the structure. In FIG. 3, 41 is a rotary shaft, 45
Is a rotor, 46 is a magnet, 47 is a yoke, 48 is a gap between the magnet 46 and the yoke 47, 49 is an insulating substrate, and 40 is a stator winding.

The second embodiment shown in FIG. 3 has a rotary shaft 41.
A cylindrical rotor 45 and a cylindrical magnet 46 fixed to the inner peripheral surface of the rotor 45, and a cylindrical yoke 47 fixed to the rotary shaft 41 via the magnet 46 and a gap 48 so as to be integrated. It has a rotating structure. A coreless stator winding 40 formed in a cylindrical shape is arranged together with an insulating substrate 42 in a gap between the magnet 46 and the yoke 47.

When the revolving shaft 41 is rotated, the stator winding 40
The magnetic flux of the magnet 46 acts on the coil to generate an induced voltage proportional to the rotation speed, and the same current control device 11 as that of the first embodiment (FIG. 1) is connected to the terminal of the stator winding 40 to set a predetermined constant value. When an electric current is applied, a braking force proportional to the electric current is generated on the rotating shaft 41. Then, the rotor 45 and the yoke 47
And are fixed to the rotary shaft 41 and rotate integrally,
Since the magnetic flux passing through the rotor 45 and the yoke 47 does not change, hysteresis loss does not occur. Also, since the stator winding is coreless and there is no iron core, hysteresis loss does not occur, there is no braking force due to hysteresis loss, and there is no change in rotation speed. The variation of the braking force does not occur as in the first embodiment.

FIG. 4 shows the braking force measured by changing the rotation speed (rotation speed) in the braking device according to the present invention and the braking device according to the prior art (especially the generator type having a stator having an iron core). In the experimental data showing the relationship with the braking torque), the solid line is the braking device of the present invention, and the broken line is the braking device according to the prior art. In the prior art, the braking force rapidly increases due to the increase of the rotation speed, whereas the braking device of the present invention shows that the braking force hardly changes even when the rotation speed changes, and is almost constant. Shows.

In the above-described first and second embodiments, the stator winding 10 or 40 has a phase difference of 3 degrees with an electrical angle of 120 degrees.
A phase winding and a star connection are desirable. In the delta connection, if there is a slight unbalanced voltage in each phase winding, a circulating current flows between the windings of each phase, which causes extra brake force, and this circulating current is generated by the current control device 11. Since it does not pass through, it is out of control and may cause a problem of impairing the linearity with respect to the rotation speed. Moreover, when the phase difference of the three phases is 120 degrees, the conduction waveform of each phase is 120 degrees conduction,
The torque ripple of the braking force is also small.

The features of the braking device of the present invention exemplified in the first and second embodiments will be listed.

(A) Comparing the required electric power in a system using a large number of brake devices, for example, when the number of revolutions is 3000 (times / minute), 5 × 10 ⁻⁴ kgm (50 gc)
In the braking device that generates the torque of m), the conventional hysteresis brake is 3 W, and 3 units per 100 units.
A power supply of 00 W is required, but a power supply of the brake control device of the present invention is 0.1 W, and a power supply of 10 W for 100 units is sufficient.

(B) Since there is no iron loss, the braking force does not change depending on the rotation speed, and a constant braking force can be applied. Therefore, there is a merit that correction by a control circuit or the like is unnecessary.

(C) A long life can be expected with the brushless motor structure.

(D) The coreless structure has no torque ripple, and the stator winding is energized at 120 degrees, so that the torque ripple is small and a highly accurate braking force can be generated.

(E) Since the stator winding has a three-phase star connection, a circulating current between the windings does not occur, so that a highly accurate braking force can be generated.

(F) Since the rotational speed can be detected from the induced voltage of the stator winding, when it is used in the tension control device,
There is an advantage that the feeding amount of the thread or the like can be accurately measured.

[0050]

As described in detail above, in the brake device of the present invention, the braking force can be controlled by the current command value, and the braking force can be kept constant regardless of the rotation speed of the rotary shaft. Therefore, it is possible to provide a highly accurate brake device that consumes less power and is used in a tension control device that winds an elongated object such as a thread, tape, or electric wire. Further, there is an effect that a rotation pulse signal can be generated from the induced voltage of the stator winding with a simple configuration to accurately measure the winding length and the yarn amount.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a structure of a brake device exemplified in a first embodiment of the present invention.

FIG. 2 is a circuit diagram of a current control device of the brake device illustrated in the first embodiment of the present invention.

FIG. 3 is a cross-sectional view showing the structure of the brake device exemplified in the second embodiment of the present invention.

FIG. 4 is a graph showing the relationship between the brake torque and the rotation speed of the brake device illustrated in the first and second embodiments of the present invention.

FIG. 5 is a schematic diagram showing a configuration of a brake device used in a conventional winding device.

[Explanation of symbols]

1 ... Rotation axis 2 ... Laura 3 ... Bracket 4 ... Bearing 5 ... rotor 5a ... rotor boss 5b ... through hole of rotor boss 6 ... Magnet 7 ... York 7b ... through-hole of yoke 8 ... void 9 ... Insulated wiring board 10 ... Stator winding 11 ... Current control device 21 ... Full wave rectifier 22 ... Power transistor 23 ... Current detection resistor 24 ... Transistor 25 ... 1st operational amplifier 26 ... Resistance 27 ... Resistance 28 ... Resistance 29 ... resistance 30 ... Capacitor 32 ... resistance 33 ... Resistance 34 ... Second operational amplifier 40 ... Stator winding 41 ... Rotary axis 45 ... rotor 46 ... Magnet 47 ... York 48 ... Air gap between magnet and yoke 49 ... Insulating substrate 100 ... Thread to be wound 101 ... Guide roller 103 ... Brake roller 104 ... Brake 105 ... Guide roller 106 ... Winding core metal 107 ... Winding motor

─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Kei Maruyama 172 Itazawa-cho, Yamatokoriyama City, Nara Nitta Stock Company Nara Factory (72) Inventor Tomohiro Agaya 172 Ikezawa-cho, Yamatokoriyama City, Nara Nitta Stock Company Nara In the factory (56) Reference JP 62-25860 (JP, A) JP 59-97951 (JP, A) JP 4-352996 (JP, A) JP 8-65955 (JP, A) ) JP-A-6-284687 (JP, A) JP-A-56-122757 (JP, A) SAIKAI 61-55229 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H02K 49/00-49/12

Claims (8)

(57) [Claims] 1. A braking device having a structure in which a braking force acts on the rotating shaft when the rotating shaft is rotated from the outside, and a magnet having N and S poles alternately magnetized in a circumferential direction, A yoke made of a magnetic material is fixed to the rotating shaft through a gap, a coreless stator winding is arranged in the gap, and a predetermined current value is controlled at the terminal of the stator winding. By connecting a possible current control device, when the rotary shaft is rotated from the outside, a current flows through the current control device due to an induced voltage generated in the stator winding, and a braking force is applied to the rotary shaft. A brake device having a structure that works. 2. The braking device according to claim 1, wherein:
The magnet is formed in a disk shape, and N poles and S poles are alternately magnetized in the circumferential direction on the end surface of the magnet. The yoke is formed of a magnetic disk and the coreless stator winding. The brake device is arranged on a plane substantially perpendicular to the rotation axis. 3. The braking device according to claim 1, wherein:
The magnet is formed in a cylindrical shape, and N poles and S poles are alternately magnetized in a circumferential direction on an inner peripheral surface of the magnet. The yoke is formed of a magnetic cylinder, and the coreless stator winding. The brake device is arranged in a cylindrical shape substantially parallel to the rotation axis. 4. The brake device according to claim 2, wherein:
A rotor integrally fixed to the rotor boss is fixed to the rotary shaft, and a magnet having N and S poles alternately magnetized in the circumferential direction is fixed to the end surface of the rotor, and is formed of the rotor boss and a magnetic material. The brake device, wherein a predetermined number of through holes in the axial direction are provided in the formed yoke. 5. The brake device according to claim 1, wherein the current control device connected to the stator winding changes the current command value by pulse width modulation (PW).
M) A brake device having a control circuit for controlling the current of the stator winding to a predetermined current value instructed by a signal. 6. The brake device according to claim 1, wherein the current control device is P
A circuit for converting a current value command signal by a WM signal into a voltage and a current control circuit in which a power transistor and a current detection resistor were connected in series were provided, and the output of the stator winding of the brake device was converted by a full-wave rectification circuit. A brake device comprising a control circuit that connects a DC voltage output to the current control circuit and controls the current of the stator winding so as to match the current value command signal. 7. The brake device according to claim 1, further comprising a converter for converting an output voltage of the stator winding into a pulse voltage proportional to a frequency of the output voltage. A braking device characterized by being provided. 8. The brake device according to claim 1, wherein the coreless stator winding is formed by star-connecting three-phase windings. .