JP6064165B2 - Drum drive - Google Patents

Description

  The present invention is used in clothing processing apparatuses such as drum-type washing machines, drum-type washing / drying machines, drum-type clothes dryers used in general homes or offices, factories, construction sites, etc. In order to stir fresh concrete, etc., solid, liquid, powder, fluid, etc. are contained in a cylindrical drum, and rotating on a rotating shaft with an angle from the vertical, the action of the gravity of the earth changes, The present invention relates to an agitated drum driving device.

  Conventionally, when switching from the synchronous operation mode to the position feedback operation mode, this type of device estimates the torque of the motor during the synchronous operation mode and sets a control constant (see, for example, Patent Document 1).

  FIG. 10 shows a conventional apparatus described in Patent Document 1. In FIG. As shown in FIG. 10, a permanent magnet motor 1 and a motor driving device 2 that controls the permanent magnet motor 1 are provided. The motor driving device 2 includes a control unit 3, a power conversion circuit 4, and current detection means 5. The control unit 3 includes a current controller 9, 10, a voltage command value generator 11, a dq / 3φ converter 12, an axis error calculator 13, a load estimator 14, an integral term initial value calculator 15, and a speed controller 16. , Control changeover switches 17, 18, subtractors 20, 21, 22, 23, PLL controller 24, and integrator 25, and current detection means 5 is motor current detection means 27, 28, 3φ / converter. 29.

  During the synchronous operation mode, by operating the load estimator 14 and the integral term initial value calculation unit 15 and then operating the control changeover switches 17 and 18, the position feedback operation mode with the q-axis current corresponding to the load torque. Thus, the occurrence of a speed change at the time of switching from the synchronous operation mode to the position feedback operation mode is suppressed.

JP 2007-037352 A

  However, in the conventional configuration, when the load torque pulsates, a period for making the frequency command constant during the synchronous operation mode is provided in order to calculate the average torque in the period, and this period is defined as the load torque pulsation period 1 Although it can drive stably by setting it as the period or more, it had the subject that it cannot respond to the non-periodic load torque fluctuation at the time of drum starting.

  The present invention solves the above-mentioned conventional problems, and is stable at the time of starting the drum with a non-periodic load torque fluctuation caused by the contents of the drum (laundry, food, waste, ready-mixed concrete, etc.). It is an object of the present invention to provide a drum driving device that can be driven in a continuous manner.

In order to solve the above-described conventional problems, a drum driving device of the present invention includes a drum having a rotation shaft having an angle with respect to vertical, a drum motor having a permanent magnet in a rotor, and driving the drum, An inverter circuit for supplying a current to the drum motor, wherein the inverter circuit includes a first operating means, a second operating means, and a switching means; and the first operating means is a magnetic pole position of the rotor The second operating means generates a signal corresponding to the magnetic pole position of the rotor, and the switching means controls the drum motor with a signal from the first operating means. After the start, the second rotation angle of the drum from the start becomes 90 degrees first.
The first operating means increases the frequency of the current supplied to the drum motor with the passage of time, and the rate of increase in the frequency is determined by the first operating means. The average increase rate in the second period following the first period is larger than the average increase rate in the first period including the time from the start of operation by the driving means until the drum motor actually starts to move. It is what.

As a result, when the drum starts with a non-periodic load torque fluctuation caused by the drum contents, the period until the drum rotates 90 degrees and the drum contents collapse due to gravity and the load torque fluctuates greatly is reduced. Stable with respect to fluctuations in the phase, current and voltage of the permanent magnet due to load torque fluctuations by operating with the first driving means independent of the magnetic pole position and switching to the second driving means after that time. Can be driven.
Further, the rotational speed of the drum can be stably accelerated.
Furthermore, the frequency of the current is increased at an optimal increase rate according to the state of the load torque, and the drum rotation speed can be stably accelerated.

  The drum driving device of the present invention can be stably driven at the time of starting of the drum accompanied by non-periodic load torque fluctuation caused by the contents of the drum.

Block diagram of drum driving apparatus according to Embodiment 1 Detailed block diagram of first operating means 72 and switching means 74 of Embodiment 1 Operation waveform diagram of first driving means 72 of embodiment 1 Detailed block diagram of second operating means 73 of embodiment 1 Detailed block diagram of motor current control unit 75 of the first embodiment Waveform diagram showing changes of each variable before and after the switching operation of the first embodiment Current vector diagram before and after the switching operation of the drum drive device of the first embodiment Sectional drawing which showed the state of the rotation angle of the drum 51 of the drum drive device of Embodiment 1 Waveform diagram showing change in output of angular velocity setter 83 during operation of the first driving means of the first embodiment Block diagram of a conventional drum drive device

  A drum driving device according to a first aspect of the present invention includes a drum having a rotating shaft having an angle with respect to vertical, a drum motor having a permanent magnet in a rotor and driving the drum, and an inverter for supplying current to the drum motor The inverter circuit includes first operating means, second operating means, and switching means, and the first operating means generates a signal independent of the magnetic pole position of the rotor. The second operating means generates a signal corresponding to the magnetic pole position of the rotor, and the switching means activates the drum motor with a signal from the first operating means, and the drum from the start-up. The signal is switched to the signal from the second operating means after the time when the rotation angle of the first becomes 90 degrees.

  As a result, when the drum starts with a non-periodic load torque fluctuation caused by the drum contents, the period until the drum rotates 90 degrees and the drum contents collapse due to gravity and the load torque fluctuates greatly is reduced. Stable against fluctuations in rotor magnetic pole position, current and voltage due to load torque fluctuations by operating with first driving means independent of magnetic pole position and switching to second driving means after that time It is possible to provide a drum drive device that can be driven automatically.

Further, the first operating means, the frequency of the current supplied to the drum motor, is intended to increase with time.

  Thereby, the rotational speed of the drum can be stably accelerated.

Furthermore, the increase rate of the frequency of the current supplied to the drum motor is higher than the average increase rate in the first period including the period from the start of operation by the first operation means until the drum motor actually starts to move. The average rate of increase in the second period following the period of 1 is larger.

  As a result, the frequency of the current is increased at an optimum increase rate in accordance with the state of the load torque, and the drum rotation speed can be stably accelerated.

In the drum driving device of the second invention, in particular, the first operating means of the first invention changes the magnitude of the current vector supplied to the drum motor in accordance with the time from activation. .

  Thereby, the optimal electric current according to the state of load can be supplied with respect to the drum motor from an inverter, and the rotational speed of a drum can be accelerated stably.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a block diagram of a drum driving device according to the first embodiment of the present invention. In the present embodiment, the drum driving device performs washing and is generally called a drum type washing machine or the like.

  In FIG. 1, a drum 51 is rotatably supported by bearings 52 and 53 in a state having an angle of 90 degrees with respect to the vertical, that is, in a state having a horizontal rotation axis, and a laundry 54 such as clothing is provided therein. Is supposed to enter.

  Here, the term “vertical” as used in the present application indicates the direction of gravity, and is synonymous with vertical or perpendicular to horizontal.

  The drum 51 includes a small pulley 62, a belt 63, a belt 60, a four-pole drum motor 60 configured by rotatably holding a rotor 59 having permanent magnets 55, 56, 57, 58 including rare earth such as neodymium and dysprosium. It is rotated by being decelerated to 1/10 through the large pulley 64.

  A resin outer container 66, a water supply valve 67, a drain valve 68, and a lid 69 are provided outside the drum 51, and washing can be performed by applying water and a detergent to the laundry 54 of the drum 51. It is possible.

  An inverter circuit 71 that supplies current to the drum motor 60 is provided. The inverter circuit 71 includes a first operating unit 72, a second operating unit 73, a switching unit 74, and a motor current control unit that controls the output current by dividing it into a first current component Id and a second current component Iq. 75. The first operating means 72 generates a signal S1 independent of the magnetic pole position of the rotor 59. The second operating means 73 generates a signal S2 corresponding to the magnetic pole position of the rotor 59. The switching unit 74 first starts the drum motor 60 by connecting the signal S1 from the first operating unit to the motor current control unit 75, and the time when the rotation angle of the drum 51 from the start becomes 90 degrees first. Thereafter, the input to the motor current control unit 75 is switched to the signal S2 from the second operating means 73.

In FIG. 1, each of S1 and S2 is shown by a single line, but in actuality, it is constituted by three sets of the second current component set value Iqr, phase θ, and electric angular velocity ω of the motor. Has been.

  Further, in the present embodiment, the switching means 74 is switched from S1 to S2 in response to the digital signal F changing after the first operating means 72 has been activated for a predetermined time.

  FIG. 2 shows a detailed block diagram of the first operating means 72 and the switching means 74 of the present embodiment.

  In FIG. 2, a timer 80 that measures the time from activation outputs a time signal t and is input to a time limiter 81, a current setting unit 82, and an angular velocity setting unit 83.

  The current setter 82 outputs to the switching means 74 as Iqr1, the angular velocity setter 83 outputs to the switching means 74 as ω1, and further passes through an integrator 86 that performs time integration of ω, and is also output as θ. .

  The switching means 74 selects S1 when the F signal is low, and selects S2 when the F signal is high, and outputs Iqr, θ, and ω signals.

  FIG. 3 shows an operation waveform diagram of the first operating means 72 of the present embodiment.

  (A) shows the logic of the signal F, (A) shows Iqr1, (C) shows ω1, and (D) shows θ1 on the horizontal axis.

  In the period in which the first driving means operates effectively, that is, in the period of 3.0 seconds from the start when the signal F is low, Iqr1 is a straight line from 3A to 6A in the first 1.0 second period. In the subsequent 2.0 seconds, 6A is maintained, and ω1 is assumed to increase linearly. As described above, the first operating means 72 changes the magnitude of the current vector supplied to the drum motor 60 according to the time from the start.

  As for the value of Iqr1, if the value is increased, the torque for driving the drum motor 60 can be increased. However, if the initial value is increased too much, the permanent magnet in the drum motor 60 is rapidly attracted and abnormal noise or May cause vibration. In order to avoid this, it is better to set a smaller value in the initial stage of startup than the value of Iqr1 set when the maximum driving torque is required.

  The motor phase θ1 is obtained by integrating ω1 over time, but is expressed using a variable that is reset to 0 when it reaches 2π (360 degrees), so the waveform is as shown in (d). At t = 3.0 seconds, θ1 is exactly 0, and the motor electrical angle is 20π radians (10 rotations = 3600 degrees) in 3.0 seconds when the first driving means operates. However, since the drum motor 60 has four poles and the pulleys 62 and 64 are decelerated by one tenth, the rotation angle of the drum 51 is ideally performed from start to finish. If it is assumed that it has been broken, it is 180 degrees (0.5 rotations).

  However, in reality, depending on the position of the drum motor 60 in the rotational direction at the time t = 0 seconds, the actual rotation of the drum motor 60 until it settles in a synchronous state varies by about a quarter of a plus or minus rotation. The rotation angle of the drum 51 for 3.0 seconds is 171 to 189 degrees, but is a value of 90 degrees or more.

When the time limiter 81 raises the F signal from low to high at t = 3.0 seconds, the switching means 74 that has received the F signal switches the signal from S1 to S2, and the second operating means 73. To switch to.

  As for Idr, in the present embodiment, 0 A is selected from the switching means 74 when the F signal is low, and -3.8 A is selected and output when it is high.

  FIG. 4 shows a detailed block diagram of the second operating means 73 of the present embodiment.

  In FIG. 4, the speed error amplifying means 90 is the difference between ω obtained from the speed setting means 89 for outputting the angular speed set value ωr of the drum motor 60 and the switching means 74, that is, PI (proportional and integral) from the speed error. The elements are acted and added to output Iqr2, and the torque is adjusted so as to achieve a set speed.

  The phase error estimator 91 receives Id, Iq, Vd, Vq, and ω from a motor current control unit 75 described later, and parameters such as an induced electromotive force constant, q-axis inductance, and resistance value of the drum motor 60. Is used to calculate the difference Δθ between the phase θ currently used by the motor current control unit 75 and the phase where the voltage equation of the drum motor 60 is established.

  In the present embodiment, (Vd−Ra · Id + ω · Lq · Iq) is divided by (Vq−Ra · Iq−ω · Lq · Id), and its arctangent function is taken and the sign is reversed. The calculated value is calculated as an error Δθ of the actual dq phase with respect to the dq coordinate used by the control.

  The convergence means 92 has a speed estimation means 93 and an integrator 94. The speed estimation means 93 uses permanent magnets 55, 56, PI (proportional / integral) so that Δθ converges to zero. The angular velocity ω2 of 57 and 58 is calculated. Further, ω2 is output as the estimated phase θ2 by calculating the time integration in the integrator 94.

  During the period when F is low, the integrator 94 is constantly updated so that Δθ is output as θ2, and the speed estimation means 93 is also constantly updated so that ω2 becomes ω. Is to be done.

  In a state where the operation of the second operating means 73 is valid, the drum motor 60 is operated without the position sensor by the action of the phase error estimator 91 and the converging means 92.

  In the present embodiment, the phase error estimator 91 uses the above-described calculation formula of Δθ, but is not limited thereto, and values related to the voltage and current supplied to the drum motor 60 and the drum motor 60 The parameter may be used to derive a value related to the phase error Δθ or the d-axis voltage difference. In short, the drum motor 60 is operated while generating a signal corresponding to the magnetic pole position of the rotor 59. Anything that can be done.

  The cosine amplifier 95 outputs an Iref value obtained by multiplying the cosine function of Δθ by the Iqr value from the switching means 74. The speed error amplifying means 90 outputs an output value during a period when F is low. The value of the internal integrator is constantly updated so that Iqr2 becomes equal to the Iref value.

FIG. 5 shows a detailed block diagram of the motor current control unit 75 of the present embodiment.
The motor current control portion 75 supplies a three-phase current from the inverter circuit 71 to the drum motor 60. The input θ value is a permanent value when the magnetomotive force due to the U-phase current is used as a reference. If the direction of the magnetic flux by the magnets 55, 56, 57, and 58, that is, the true d-axis phase is correctly matched, the input Idr is the first parallel to the magnetic flux of the permanent magnets 55, 56, 57, and 58. 1 and Iqr is a second current component that is orthogonal to it and advanced in phase by +90 degrees (π / 2), and is controlled to a desired current vector.

  5, current error amplifiers 98 and 99, coordinate converters 100 and 101, a PWM power module 103, a DC power supply 104, and a current detection circuit 105 are included. The current error amplifier 98 includes a set value Idr and a coordinate converter 101. The difference in the output Id is calculated as PI (proportional / integral) and output as Vd.

  The current error amplifier 99 calculates the difference between the set value Iqr obtained from the switching means 74 and the output Iq of the coordinate converter 101 in a similar manner PI (proportional / integral) and outputs it as Vq.

  The coordinate converter 100 receives Vd, Vq, and θ output from the current error amplifiers 98 and 99 and converts them into Vu, Vv, and Vw using Equation 1 or the like.

  As described above, the use of the three phases has an effect that the drum motor 60 and the inverter circuit 71 have a relatively simple configuration and can transmit power continuously and smoothly. It is not limited, and may be two-phase, four-phase, five-phase, and the like.

  The PWM power module 103 is composed of six stone IGBTs (not shown), an electronic circuit, and the like. The PWM power module 103 receives a DC voltage of 280 V from the Vu, Vv, Vw and the DC power supply 104, and performs PWM (pulse width modulation). While performing, three-phase alternating current is output from U, V, and W, and a current of several amperes is supplied to the drum motor 60. Specifically, the microcomputer is configured as a single chip. It is configured as an integrated body of a pulse width modulator and a power portion provided in a separate package.

  For the U phase and the W phase, the instantaneous values of the current values Iu and Iw are detected by passing through the detection elements 106 and 107 of the current detection circuit 105 and input to the coordinate converter 101.

  Note that the detection elements 106 and 107 detect a current value from the magnetic field by detecting a current value from a magnetic path by a current to be detected, or a voltage drop of a resistance called a shunt resistor. Things are available.

  Although the V-phase current Iv is not detected in the present embodiment, Iv is also obtained from the input Iu and Iw from the relationship of Iu + Iv + Iw = 0. For example, the d-axis current Id and the q-axis current Iq are calculated using θ.

  FIG. 6 is a waveform diagram showing the change of each variable before and after the switching operation by the output F of the switching means 74 of the present embodiment, with the time on the horizontal axis slightly enlarged.

  6A and 6B, both are input / output signals of the switching means 74. (A) is Iqr1 by a broken line, Iqr2 by a dashed line, Iqr by a solid line, (A) is ω1 by a broken line, ω2 by a dashed line, and ω by a solid line. (C) indicates θ1 by a broken line, θ2 by a one-dot chain line, and θ by a solid line.

  Due to the action of the switching means 74, θ = θ1 at t <3.0 seconds, and θ = θ2 at t> 3.0 seconds.

  As for Iqr2 at t <3.0 seconds, the integral component is continuously updated so that the output Iref value from Iqr1 through cosine amplifier 95 becomes the output of speed error amplifying means 90, that is, Iqr2, as described above. , Ω2 are set to be the same value as ω1 and θ2 is always set to be equal to Δθ.

  Here, Iqr1, ω1, and θ1 at t> 3.0 seconds are not described because they have little meaning.

  FIG. 7 shows the current vector before and after the switching operation by the switching means 74 on the true dq coordinate in the drum driving device of the present embodiment.

  Iqr1, which is the Iqr value immediately before switching, has a length of 6A, which is the value of Iqr1, but has a slope of Δθ in the first quadrant as the direction, and the true q-axis component is a cosine amplifier. An output of 95, that is, an Iref value obtained by multiplying Iqr1 by a cosine of Δθ, and immediately after switching, a change to Iqr2 = Iref is made.

  As a result, an effect similar to that of setting the initial value of the integrator for speed control described in Patent Document 1 can be obtained.

  In the case of a washing machine or the like, the load torque is suddenly reduced at the moment when the laundry 54 collapses, so that further overshoot of the angular velocity of the drum 51 is likely to occur. However, the Iref value is It is also effective in suppressing such overspeed.

  On the other hand, with respect to the phase θ, since θ1 is exactly 0 (a multiple of 2π) at the time of switching, by adding Δθ to this (that is, jumping phase advance), FIG. As shown in the figure, correction from the γ1 axis to the correct d-axis is performed, and thereafter, the second operation means 73 can be operated satisfactorily.

  In the present embodiment, the calculation of the desired values of Vd and Vq after switching is somewhat complicated for the current error amplifiers 98 and 99 that perform PI type error amplification. Is not operated at the time of switching, but there is no problem with respect to these currents because the design can respond in a relatively short time.

  FIG. 8 is a cross-sectional view showing a state of the rotation angle of the drum 51 of the drum driving device of the present embodiment.

  8, (a) shows the state of the drum 51 at the start of activation, and shows a state where the laundry 54 is stacked in the drum.

  Point O is the center of the drum 51 and serves as a rotation axis.

  Similarly, (a) shows a state in which the drum 51 is first rotated 90 degrees from the starting time shown in (a). In (a), when the upper surface of the laundry 54 is stacked so as to be horizontal, the positional relationship between the drum 51 and the laundry 54 is similarly maintained until the time point (a).

  (C) is the state where the rotation angle of the drum 51 from the start is 100 degrees. When the rotation of the drum 51 exceeds 90 degrees, the gravity that has been working in the direction to keep the laundry 54 that has been stacked up until then will work in the direction of turning away. (C) is a state in which a part of the laundry 54 falls and is struck against the inner wall of the drum 51 and stacked again.

  In the process from (a) to (c), the situation of the drum 51 varies greatly. First, at a stage where a part of the laundry 54 is falling in the drum 51, the load corresponding to the falling laundry 54 is released from the rotational movement of the drum 51, so the load on the drum motor 60 is reduced. . Next, at the moment when the dropped laundry 54 is struck against the inner wall of the drum 51, the drum 51 receives a large impact and generates a vibration in the vertical direction. It becomes the size of.

  Here, the control suitable for this situation is considered from the characteristics of the first operating means and the second operating means.

  First, the first operating means supplies a current independent of the magnetic pole position of the rotor 59, and if the magnitude of the current vector that can be rotated at the assumed load is secured, Even if vibration or load fluctuation occurs, the current supply is continued.

  On the other hand, the second operating means supplies a current corresponding to the magnetic pole position of the rotor 59. In the present embodiment, the magnetic pole of the rotor 59 is determined from the current flowing through the drum motor 60, the applied voltage, the angular velocity, and the like. The position is estimated and a current corresponding to the result is supplied. In contrast to this estimation, a sudden increase or decrease in load or vibration of the drum 51 induces large fluctuations in current, voltage, and angular velocity, and causes large errors. Therefore, it is stable when driven by the second driving means in this situation. May not be possible. Therefore, in the process from (a) to (c), the driving by the first operating means is suitable.

  In the present embodiment, it is assumed that a part of the laundry 54 falls when the rotation angle of the drum 51 is 100 degrees. However, this rotation angle varies depending on the water content of the laundry 54 and the state of entanglement. The only universal condition is that it exceeds 90 degrees.

  (D) is a state where the rotation angle of the drum 51 is 180 degrees.

Also in the process from (c) to (d), the laundry 54 that has reached the upper side in the vertical direction in the drum 51 falls and is struck down, but this process occurs continuously thereafter. Therefore, the laundry 54 is always a mixture of the following three states. That is, one that is rotating in conjunction with the drum 51, one that is falling off the inner wall of the drum 51, and one that is being struck against the inner wall of the drum 51. Considering the total load on the drum motor 60, the load received from the laundry 54 in this process is the sum of the above three states, and the sum is almost constant as long as it is continuously generated.

  In this state, disturbance to the driving of the second driving means is small and stable driving can be realized. In such a situation, the second driving means, which can be driven while estimating the load state, can be operated with higher accuracy and energy saving than the first driving means. Driving with two driving means is suitable.

  As described above, according to the present embodiment, the switching unit 74 starts the drum motor 60 with the signal from the first operating unit 72, and after the time when the rotation angle of the drum 51 from the start becomes 90 degrees first. In addition, by switching to the signal from the second operating means 73, when the drum 51 is started with non-periodic load torque fluctuation caused by the contents of the drum 51, the drum 51 rotates 90 degrees and the drum 51 is caused by gravity. The period until the contents collapse and the load torque largely fluctuates is operated by the first operating means 72 independent of the magnetic pole position of the rotor 59, and after that time, the load is changed to the second operating means 73. It is possible to provide a drum driving device that can be stably driven against fluctuations in the magnetic pole position, current, and voltage of the rotor 59 caused by torque fluctuations.

  In the present embodiment, the angular velocity of the drum motor 60 set by the first driving means is linearly increased, that is, constant acceleration, but is not limited thereto. When a large load is applied at the time of activation, for example, when the laundry 54 contains a large amount of water, it is possible to drive more stably with a small acceleration at the beginning of activation driven by the first driving means. This is the first period. However, when the acceleration is small, there is a problem that it takes a long time to reach a desired speed. In order to avoid this, the acceleration may be increased when a predetermined angular velocity at which a stable rotational force is obtained by inertia is reached. This is the second period. That is, the average increase rate of the frequency of the current supplied to the drum motor 60 is higher than the second period after the drum motor 60 following the first period starts moving than the first period including the period until the drum motor 60 starts moving. The average rate of increase over the period is greater. Thereby, the time to reach a desired speed can be shortened while stably starting. FIG. 9A is a waveform diagram showing this acceleration state. Since the acceleration is small in the first period, the inclination of the angular velocity is small, and in the second period, the inclination of the angular velocity is large because the acceleration is large.

  Further, the acceleration during the first period and the second period may change continuously. For example, if the acceleration is linearly changed during driving by the first driving means, the change in speed is shown in FIG. As shown in Fig. 9 (b), it becomes a quadratic function, the acceleration at the initial stage of startup is small, the acceleration can be increased as the angular velocity increases, and the time to reach the desired speed can be shortened while starting up stably. be able to.

  It is also possible to provide a third period, a fourth period, and the like after the second period. For example, when the desired angular velocity is reached in the second period, the third period after which the acceleration is zero. By providing this, it is possible to stably switch to the second driving means while maintaining a desired angular velocity.

  In the present embodiment, the coordinate converters 100 and 101 use simple ones that add the direction cosines using only the cosine functions (cosine) shown in Equations 1 and 2, respectively. As long as the microcomputer environment can calculate the sine function (sine) in a short time, Formula 3 and Formula 4 may be used. In some cases, the calculation time can be shortened, and can be used appropriately. .

  In the present embodiment, the drum motor 60 is configured to rotationally drive the drum 51 via the pulleys 62 and 64 and the belt 63, and there is a constant mechanical reduction (1/10). Therefore, the torque required for the drum motor 60 can be reduced, which is advantageous for downsizing and cost reduction of the apparatus.

  However, the pulleys 62 and 64 and the belt 63 are not necessarily used. For example, a gear (gear) is used for deceleration, or the drum 51 and the drum motor 60 are directly connected to each other without mechanical deceleration. In any case, a viewpoint is set on the rotation angle of the drum 51 to be finally driven.

  Further, in the present embodiment, the drum rotation axis has an angle of 90 degrees with respect to the vertical, that is, shows a drum driving device in which the rotation axis is horizontal. However, when the drum moment caused by the earth's gravity, that is, the torque, is generated to a greater or lesser extent, with an angle of about 10 degrees with respect to the vertical, for example, a washing machine called a vertical type is configured. Even if it exists, the tendency for the torque by the effect | action of gravity to generate | occur | produce will fully generate | occur | produce, and the effect of this invention can be anticipated.

  As described above, the drum driving apparatus according to the present invention generates a current that needs to be supplied from the inverter circuit to the drum motor in a state where the rotation angle of the drum that requires a large torque is approximately 90 degrees after the start. Since it can be effectively reduced, a vertical drum driving device, a drum type drum driving device, a drum type washing / drying machine having a rotating shaft of a drum having an angle with respect to the vertical used in general households, etc. It may be a drum-type dryer or a vertical washing machine, and may have improved usability by using a rotary shaft having an angle from the vertical. Furthermore, it can also be applied to applications such as a rotary cooker that handles food, a rotating drum that treats waste, and a concrete mixer that stirs concrete powder and earth and sand.

Reference Signs List 51 Drum 55, 56, 57, 58 Permanent magnet 59 Rotor 60 Drum motor 71 Inverter circuit 72 First operating means 73 Second operating means 74 Switching means 93 Speed estimating means 89 Speed setting means 90 Speed error amplifying means

Claims (2)

A drum having a rotation axis having an angle with respect to the vertical;
A drum motor having a permanent magnet in the rotor and driving the drum;
An inverter circuit for supplying current to the drum motor,
The inverter circuit has first operating means, second operating means and switching means,
The first operating means generates a signal independent of the magnetic pole position of the rotor;
The second operating means generates a signal corresponding to the magnetic pole position of the rotor,
The switching means starts the drum motor with a signal from the first operating means, and the signal from the second operating means after the time when the rotation angle of the drum from the start is 90 degrees for the first time. in the drum drive system to switch to,
The first operating means increases the frequency of the current supplied to the drum motor as time elapses, and the rate of increase in the frequency is such that the drum motor actually starts moving from the start of operation by the first operating means. A drum driving device characterized in that the average increase rate in the second period following the first period is larger than the average increase rate in the first period including the above . 2. The drum driving apparatus according to claim 1, wherein the first operation unit changes a magnitude of a current vector supplied to the drum motor in accordance with a time from activation.