JPH04236983A - Washing machine - Google Patents

Abstract

PURPOSE:To reduce abrasion of a stopping pawl for prohibiting rotation of a rotary shaft of a motor for rotating a washing tank. CONSTITUTION:An inverter circuit INV for driving a motor 6 for rotating a washing tank and rotation position detecting means LS1, LS2 for detecting if a clothing in/out port 3b provided in the washing tank 3 is at a predetermined position are provided. When the rotation position detecting means LS1, LS2 detect that the clothing in/out port 3b is at the predetermined position, the rotation direction of an ignition signal for making a control rectifier element for phase control conductive at the inverter circuit INV is inverted, and the phase rotation direction of the output voltage of the inverter circuit is inverted, so the rotation direction of the motor 6 is inverted. By holding the washing tank 3 at a predetermined rotation position, stopping pawls 11, 12 are engaged with a gear 8 to prohibit rotation of the washing tank 3.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine that performs washing by rotating a drum-shaped washing tub provided in an outer tub.

0002

2. Description of the Related Art FIG. 7 is a schematic perspective view of a conventional washing machine of this type. An outer tub 2 is supported within a frame 1, and a horizontal drum-shaped washing tub 3 made of synthetic resin is rotatably supported within the outer tub 2. The upper surface of the frame 1 and the upper circumferential surface of the outer tub 2 are provided with clothing openings (not shown) through which clothing can be taken in and out. Further, a clothes entrance/exit (not shown) is also provided in a part of the outer peripheral surface of the washing tub 3. On the front side of the upper surface of the frame 1, there is provided a group of operation keys 4 for instructing the start of washing, the contents of washing, etc. The clothing entrance/exit provided on the top of the frame 1 is covered by the lid 5.
It can be opened and closed.

FIG. 8 is a rear view of the inside of the frame 1, and FIG.
is a vertical cross-sectional view of the outer tub 2 and the washing tub 3. A three-phase motor 6 is attached to the lower surface of the outer tank 2, and a small-diameter pulley 7 and a gear 8 are attached to its rotating shaft 6a. Washing tub 3
A large-diameter pulley 9 is attached to the rotating shaft 3a for rotating the , and a V-belt 10 is stretched between the pulleys 7 and 9. A permanent magnet M is attached to the surface of the pulley 9 facing the outer surface of the outer tank 2. Two reed switches LS1 and LS are provided on the outer surface of the outer tank 2 at positions facing the permanent magnets M and separated by an appropriate distance in the circumferential direction of the pulley 9.
2 is installed. Reed switch LS1, LS2
A signal indicating that the permanent magnet M has been detected is given to a control circuit (not shown). On the sides of the gear 8 attached to the rotating shaft 6a of the motor 6, the intermediate part is rotatably supported, and the ends of the gear 8 are engaged with and detachable from the gear 8. They are spaced apart in the direction. The tip side of the locking claws 11 and 12 and the spring support part 13
, 14 are tensioned between coil springs 15, 16, which urge the locking claws 11, 12 so that the tips of the locking claws 11, 12 are separated from the gear 8.

The proximal ends of the locking claws 11 and 12 are connected via a connecting pin 17, one end of a wire 18 is attached to the connecting pin 17, and the other end of the wire 18 is connected to a wire of a torque motor 19. It is attached to the attachment part 19a. When the torque motor 19 is rotated in one direction,
Pull the wire 18 toward the torque motor 19 side and lock the locking claw 1.
When the ends of the wires 1 and 12 move toward the gear 8 side and rotate in the other direction to loosen the tension on the wire 18, the locking claws 11 and 1
The tips of the gears 2 and 2 are separated from the gear 8 by the urging force of the coil springs 15 and 16. A clothing opening 3b is provided in a part of the outer circumferential surface of the washing tub 3 and can be opened and closed by a sliding lid 20 that slides along the outer circumferential surface. Further, on the inner circumferential surface of the washing tub 3, baffles 3c, 3 having a triangular cross section, are formed to bulge toward the axis of the washing tub 3.
c, 3c are arranged at three equal intervals in the circumferential direction. The reed switches LS1, LS2 and the mounting positions of the permanent magnet M are associated with each other so that the permanent magnet M is located between the reed switches LS1 and LS2 when the clothing opening 3b is at the uppermost position.

Next, the operation of this washing machine will be explained. The lid 5 is opened and the clothes to be washed are sequentially put into the washing tub 3 through the respective clothes entrances and exits. And clothes entrance 3 of washing tub 3
After closing b with the sliding lid 20, the lid 5 is closed and a desired key of the operation key group 4 is operated. Then, after water is supplied to the washing tub 3, the three-phase motor 6 is driven, and rotational force is applied to the washing tub 3 via the V-belt 10, causing the washing tub 3 to rotate in one direction. When the washing tub 3 rotates in one direction for a predetermined period of time, the direction of rotation is then reversed, and the washing tub 3 is rotated in the other direction for a predetermined period of time, and this operation is repeated to perform washing. The washing is finished,
When rinsing is completed, the water in the washing tub 3 is drained, and then the washing tub 3 is rotated in one direction again to dehydrate the washed clothes. When the dewatering process is completed, hot air is blown into the washing tub 3 to dry the washed clothes. When this drying process is completed, the power supply to the three-phase motor 6 is temporarily stopped, and a predetermined braking is performed to stop the rotation of the washing tub 3. Then again 3
Power is supplied to the phase motor 6, and the three-phase motor 6 is then rotated at a low speed to rotate the washing tub 3, for example, in the direction indicated by the arrow L.

[0006] When the reed switch LS2 detects the permanent magnet M, that is, when the clothing entrance/exit 3b is in the uppermost position, the voltage of two phases of the three-phase voltages feeding the three-phase motor 6 is activated by the relay. The direction of rotation of the three-phase motor 6 is reversed by using and replacing the three-phase motor 6. Then, the washing tub 3 rotates in the reverse direction in the direction indicated by the arrow R, and when the reed switch LS1 detects the permanent magnet M again, the two-phase voltage is switched back to its original state and the three-phase motor 6 is rotated in the reverse direction again. let me,
Rotate the washing tub 3 in the direction shown by arrow L. With this operation, the washing tub 3 is rotated back and forth so that the permanent magnet M is located between the reed switches LS1 and LS2, and the clothes opening 3b is held at the uppermost position.

On the other hand, when the reed switch LS2 first detects the permanent magnet M, it drives the torque motor 19 and starts pulling the wire 18 against the urging force of the coil springs 15 and 16. Then, the locking claw 11,
12 gradually approaches the gear 8, and when the clothing opening 3b is held at the uppermost position, the locking pawls 11 and 12 engage with the gear 8, and the three-phase motor 6 The rotating shaft 6a is prevented from rotating, thereby preventing the washing tub 3 from rotating, and the power supply to the three-phase motor 6 is stopped to complete a series of washing operations. Thereafter, the user operates the lid 5 upward, slides the sliding lid 20 of the clothes entrance 3b of the washing tub 3 to open the clothing entrance 3b, and takes out the washed clothes from the washing tub 3. When commanding the start of the next washing operation, the torque motor 19 is first driven to loosen the tension on the wire 18, causing the locking pawls 11 and 12 to separate from the gear 8, and then the above-mentioned washing operation is started. Start operation. In this way, by stopping the washing tub 3 at a predetermined rotational position, even if the clothes in the washing tub 3 are concentrated at one of the baffle 3c positions, the weight of the clothes prevents the clothes from being concentrated. Washing tub 3 with the part at the lowest position
The rotation of the washing tub 3 does not stop at the rotation position.

[0008]

[Problems to be Solved by the Invention] By the way, in order to hold the washing tub at a predetermined rotational position, the direction of rotation of the three-phase motor can be changed by changing the voltage of two phases of the three-phase voltage supplied to the three-phase motor using a relay. If the voltages of the two phases are switched, the current of the three-phase motor will be cut off instantaneously, and even if the two-phase voltages are switched, the current will not respond immediately, resulting in
Phase motor response is poor. Therefore, the rotation amount of the washing tub becomes large, and the rotating position of the washing tub when the rotation of the washing tub is stopped varies. Also, when the washing tub is rotating back and forth with a large amount of rotation, the gear Since the locking pawl approaches and makes contact with the locking pawl, there is a problem that the locking pawl is easily worn out and its function is quickly impaired. In view of such circumstances, the present invention can stop the washing tub at a predetermined rotational position with high precision,
To provide a washing machine in which a locking pawl for preventing rotation of a washing tub is less worn.

[0009]

[Means for solving the problems] A washing machine according to the present invention includes:
A washing machine comprising a drum-shaped washing tub, a rotational position detection means for detecting that the washing tub is at a predetermined rotational position, and a motor for rotationally driving the washing tub, the washing machine generating a voltage for driving the motor. and means for reversing the phase rotation of the output voltage of the inverter circuit when the rotational position detection means detects a predetermined rotational position of the washing tub.

0010

[Operation] The output voltage of the inverter circuit drives the motor that rotates the washing tub. When the rotational position detection means detects that the washing tub is at a predetermined rotational position, the phase rotation of the output voltage of the inverter circuit is reversed. When the phase rotation of the output voltage is reversed, the direction of rotation of the motor is reversed while the motor continues to be energized. This improves the responsiveness of reversing the rotational direction of the motor, and reduces the amount of reciprocating rotation of the washing tub.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below with reference to drawings showing embodiments thereof. FIG. 1 is a schematic perspective view of a washing machine according to the present invention. An outer tub 2 shaped like a horizontal drum is supported within a frame 1, and a washing tub 3 made of synthetic resin and shaped like a horizontal drum is rotatably supported within the outer tub 2. The upper surface of the frame 1 and the upper circumferential surface of the outer tub 2 are provided with clothing openings (not shown) for taking in and out clothing at opposing positions, respectively. Further, a portion of the outer circumferential surface of the washing tub 3 is also provided with a clothing opening, which will be described later, and which can be opened and closed by a sliding lid (not shown). On the front side of the upper surface of the frame 1, a group of operation keys 4 are provided for instructing the start of washing, the contents of washing, etc. A clothing entrance and exit provided on the upper surface of the frame 1 can be opened and closed by a lid 5.

FIG. 2 is a rear view of the inside of the frame 1, and FIG.
is a vertical cross-sectional view of the outer tub 2 and the washing tub 3. A three-phase motor 6 is attached to the lower surface of the outer tank 2, and a small-diameter pulley 7 and a gear 8 are attached to its rotating shaft 6a. An inverter circuit INV for supplying a driving voltage to the motor 6 is provided at the bottom of the frame 1. A large-diameter pulley 9 is attached to a rotating shaft 3a for rotating the washing tub 3, and a V-belt 10 is stretched between the pulleys 7 and 9. A permanent magnet M is attached to the pulley 9 on a surface facing the outer surface of the outer tank 2. Two reed switches LS1 and LS2 are mounted on the outer surface of the outer tank 2 at positions facing the permanent magnet M and spaced apart by an appropriate length in the circumferential direction of the pulley 9. On the sides of the gear 8 attached to the rotating shaft 6a of the motor 6, the intermediate part is rotatably supported, and the ends of the gear 8 are engaged with and detachable from the gear 8. They are spaced apart in the direction. Coil springs 15, 16 are installed between the tips of the locking claws 11, 12 and the spring supports 13, 14.
is stretched, thereby urging the locking claws 11, 12 so that the tips of the locking claws 11, 12 are separated from the gear 8.

The proximal ends of the locking claws 11 and 12 are connected via a connecting pin 17, one end of a wire 18 is attached to the connecting pin 17, and the other end of the wire 18 is connected to a wire of a torque motor 19. It is attached to the attachment part 19a. When the torque motor 19 is rotated in one direction,
Pull the wire 18 toward the torque motor 19 side and lock the locking claw 1.
When the tips of wires 1 and 12 move toward the gear 8 and rotate in the other direction, the tension on the wire 18 is loosened and the locking pawl 11
, 12 are separated from the gear 8 by the urging force of the coil springs 15, 16. A clothing opening 3b is provided in a part of the outer peripheral surface of the washing tub 3 and can be opened and closed by a washing lid 20 that slides along the outer peripheral surface. Further, on the inner circumferential surface of the washing tub 3, three baffles 3c, 3c, 3c having a triangular cross section and bulging toward the axis of the washing tub 3 are arranged at three equal intervals in the circumferential direction. The mounting positions of the reed switches LS1, LS2 and the permanent magnet M are correlated so that the permanent magnet M is located between the reed switches LS1 and LS2 when the clothing opening 3b is at the uppermost position.

FIG. 4 is a circuit diagram showing a control circuit for the three-phase motor 6. As shown in FIG. The voltage of the three-phase AC power supply 3P is input to the rectifier circuit REC via a switch (not shown). Rectifier circuit R
The output voltage rectified by EC is sent to the inverter circuit INV.
The output voltage is supplied to the three-phase motor 6 as the drive voltage for the three-phase motor 6. The control unit CTR has
Detection signals from the reed switches LS1 and LS2 are applied, and an inversion command signal output from the control unit CTR is applied to the inverter circuit INV. When the inverter circuit INV is given an inversion command signal while generating an output voltage, the inverter circuit INV has six stages (not shown) that give an ignition signal to six control rectifying elements (not shown) that control conduction of the input voltage. The direction of rotation of the ring counter is reversed as shown in the timing chart of the firing signal shown in Figure 5, and if the direction of rotation of the ring counter is reversed, the phase rotation of the output voltage of the inverter circuit INV is reversed. . Therefore, the direction of rotation of the three-phase motor 6 driven by the output voltage of the inverter circuit INV can be reversed.

[0015] When the rotational direction of the three-phase motor 6 is reversed in this way, the power supply to the three-phase motor 6 is cut off even momentarily, as in the case of exchanging the voltages of two phases among the three-phase voltages. The three-phase motor 6 will immediately reverse rotation. In addition, in Figure 5, the frequency of the output voltage is 40H.
The timing of ignition in the case of z is shown. Next, the operation of the washing machine configured as described above will be explained with reference to the flowchart of FIG. 6 showing the control contents of the control section. First, the lid 5 is opened and the clothes to be washed are sequentially put into the washing tub 3 through the respective clothes entrances and exits. After closing the clothes entrance 3b of the washing tub 3 with the sliding lid 20, the lid 5 is closed and a desired key of the operation key group 4 is operated. Then washing tub 3
After water is supplied, the three-phase motor 6 is driven, and rotational force is applied to the washing tub 3 via the V-belt 10, causing the washing tub 3 to rotate in one direction. When the washing tub 3 rotates in one direction for a predetermined period of time, the direction of rotation is then reversed, and the washing tub 3 is rotated in the other direction for a predetermined period of time, and this operation is repeated to perform washing. When washing is completed and rinsing is completed, the water in the washing tub 3 is drained, and then the washing tub 3 is rotated in one direction again to dehydrate the washed clothes. When the dewatering process is completed, hot air is blown into the washing tub 3 to dry the washed clothes.

When this drying process is completed, the three-phase motor 6
The rotation of the washing tub 3 is stopped by temporarily stopping power supply to the washing tub 3 and applying a predetermined brake. Thereafter, power is supplied to the three-phase motor 6 again to rotate the three-phase motor 6 at a low speed (S1), and the washing tub 3 is rotated, for example, in the counterclockwise direction indicated by the arrow L. Then, the reed switch LS1 detects the permanent magnet M and turns on, while the reed switch LS2 is not turned on, that is, the permanent magnet M detects the permanent magnet M and turns on.
2 (S2),
The three-phase motor 6 is driven until this state is reached. When it is determined that the reed switch is located between LS1 and LS2, the torque motor 19 is driven (S3).
, the wire 18 begins to be pulled against the urging force of the coil springs 15 and 16. Next, reed switch LS2
is turned on (S4), and the reed switch L is turned on (S4).
When determining that S2 is turned on, the control unit CTR gives an inversion command signal to the inverter circuit INV to invert the phase rotation of the output voltage of the inverter circuit INV (S5
). As a result, the 3-phase motor 6 can be
The rotational direction of the phase motor 6 is immediately reversed to the right rotational direction indicated by the arrow R (S6), and the permanent magnet M approaches the reed switch LS1.

Next, it is determined whether or not the washing tub 3 is at a predetermined rotational position at which the three-phase motor 6 can be stopped (S7). Wait until the stop point 6 is reached, and when it is determined that the stop point has come, apply DC voltage to the 3-phase motor 6 and start the 3-phase motor 6.
The rotation of the phase motor 6 is stopped by the DC brake (S
8). At this time, the locking pawls 11 and 12 operated by the torque motor 19 are engaged with the gear 8 to prevent the rotation shaft 6a of the three-phase motor 6 from rotating. and 3 phase motor 6
If it is determined that the rotation has been prevented (S9), the power supply to the three-phase motor 6 is stopped,
The control operation for stopping the washing tub 3 at a predetermined rotational position is completed.

Furthermore, when the washing tub 3 is rotated clockwise in the direction opposite to the rotation direction described above, that is, in the direction indicated by the arrow L, it is determined whether or not the reed switch LS1 is turned on (S10).
). When it is determined that the inverter circuit INV is turned on, the control unit CTR gives an inversion command signal to the inverter circuit INV and inverts the phase rotation of the output voltage of the inverter circuit INV in the same manner as described above (S11). As a result, the rotational direction of the three-phase motor 6 is immediately reversed, and the washing tub 3 is rotated in the counterclockwise direction indicated by the arrow L (S12). Then, the permanent magnet M approaches the reed switch LS2. Next, 3-phase motor 6
It is determined whether or not the washing tub 3 is at a predetermined rotational position at which it can be stopped (S7), and it waits until the 3-phase motor 6 stops. When it is determined that the 3-phase motor 6 has stopped, the 3-phase motor is rotated in the direction indicated by the arrow L. The control operation for stopping the washing tub 3 from rotating and stopping the washing tub 3 at a predetermined rotational position is completed in the same manner as when the washing tub 3 is rotated.

When the washing tub 3 is stopped at a predetermined rotational position in this manner, the clothes opening 3b is always located at the uppermost position, regardless of whether the washing tub 3 is rotated in the direction of arrow L or arrow R. I will do it. Therefore, after operating the lid 5 upward, the sliding lid 20 of the clothes entrance 3b of the washing tub 3 is operated to open the clothing entrance 3b, and the washed clothes are taken out from the washing tub 3. Note that when a command to start the washing operation is given, the torque motor 19 is first driven to loosen the tension on the wire 18, and after separating the locking pawls 11 and 12 from the gear 8, the above-mentioned washing operation is started. It turns out. In this way, when the rotation of the washing tub 3 is stopped, even if the clothes in the washing tub 3 are concentrated at one of the baffles 3c, the weight of the clothes will cause the clothes to be placed at the lowest position. The rotation of the washing tub 3 does not stop at the rotational position of the washing tub 3.

The washing machine of the present invention has a three-phase motor 6.
The rotation direction of the three-phase motor 6 is reversed by reversing the phase rotation of the output voltage of the inverter circuit INV for driving the three-phase motor 6.
The current is not cut off even momentarily, the three-phase motor can be quickly reversed, and the responsiveness of the three-phase motor 6 is improved. This prevents the rotational position of the washing tub 3 from varying greatly when it is stopped. In addition, since the amount of rotation of the washing tub back and forth is reduced, the period of contact between the locking claws 11, 12 and the gear 8 is shortened, and the wear of the locking claws 11, 12 is significantly reduced. The reliability of the function of preventing rotation can be greatly increased. In addition, in this embodiment, the washing tub 3
is driven by a three-phase motor 6, but it is not limited to a three-phase motor. Further, even if the washing tub 3 is shaped like a vertical drum and its rotation is stopped when the clothes opening reaches the frontmost position of the frame 1, the same effect can be obtained by applying the present invention.

[0021]

As described in detail above, the present invention reverses the phase rotation of the output voltage of the inverter circuit that supplies power to the motor that rotates the washing tub when it is detected that the washing tub is at a predetermined rotational position. to reverse the rotation direction of the motor. Therefore, when reversing the rotation direction of the motor, the motor current is not cut off and the motor immediately reverses, improving responsiveness.
The amount of reciprocating rotation required to hold the washing tub at a predetermined rotational position is reduced, the contact time between the locking pawl and the gear is shortened, and wear of the locking pawl can be significantly reduced. Also,
Since the amount of reciprocating rotation of the washing tub is reduced, excellent effects such as being able to reduce variations in the rotation stop position of the washing tub can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a schematic perspective view of a washing machine according to the present invention.

FIG. 2 is a rear view of the frame in FIG. 1;

3 is a longitudinal sectional view of the outer tub and washing tub in FIG. 1. FIG.

FIG. 4 is a circuit diagram of a control circuit for a three-phase motor.

FIG. 5 is a timing chart of a firing signal of an inverter circuit.

FIG. 6 is a flowchart showing control details of a control unit.

FIG. 7 is a schematic plan view of a conventional washing machine.

8 is a rear view of the inside of the frame in FIG. 7. FIG.

9 is a longitudinal sectional view of the outer tub and the washing tub in FIG. 7. FIG.

[Explanation of symbols]

1 Frame 2 Outer tank ３　　　　　Washing tub 3b Clothes entrance 6 3 phase motor 8 Gears 11, 12 Locking claw 15, 16 Coil spring 19 Torque motor INV Inverter circuit

Claims (1)

[Claims] 1. A washing machine comprising a drum-shaped washing tub, rotational position detection means for detecting that the washing tub is at a predetermined rotational position, and a motor for rotationally driving the washing tub, the washing machine comprising:
The washing machine includes an inverter circuit that generates a voltage for driving the motor, and a means for reversing the phase rotation of the output voltage of the inverter circuit when the rotational position detection means detects a predetermined rotational position of the washing tub. A washing machine with special features.