JPH0531021B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a motor actuator for transmitting the rotational output of a motor to an operating member of a controlled device via a clutch and a heart-shaped cam.
In particular, it concerns the method of driving the clutch and the motor in chronological order during the return of the actuating member.

Prior Art This type of motor actuator is used as a drive source for a drain valve of a washing machine, a ventilation fan shutter, or a damper for a refrigerator as a controlled device.

For example, the invention disclosed in Japanese Patent Application Laid-Open No. 129097/1983 uses a motor actuator as a driving source for a drain valve of a washing machine. In that invention, the rotational force of the motor is transmitted to a pulley via a clutch and a reduction gear, and the winding force of this pulley causes a drain valve to be biased in the closing direction by a return spring. It is driven in the direction of opening. In this case, the clutch is operated by an electromagnetic solenoid.

Once winding is complete, the motor automatically stops, but the clutch remains engaged. For this reason, the return force of the drain valve spring is increased by the deceleration gear, and
It acts on the rotor of the motor via the clutch. During this time, since the motor is applying a predetermined rotational force based on static torque, the drain valve remains open regardless of whether the motor is stopped.

However, if the clutch is then set to the OFF state, the static torque from the motor is cut off by the clutch and no longer acts on the output gear, so the drain valve is biased against the return spring. Then, while rotating the gear train, it almost instantly returns to the closed direction. At this time, since the elasticity of the return spring is set to be strong in order to ensure a reliable closed state, a large impact force is applied when the drain valve returns, and this generates a large impact noise.

OBJECT OF THE INVENTION Accordingly, an object of the present invention is to prevent impact force from being applied and at the same time to prevent impact noise when a controlled device such as a drain valve is reset.

SUMMARY OF THE INVENTION Therefore, the present invention provides a motor, a heart-shaped cam rotationally driven by the motor, a clutch interposed in a path for transmitting the rotation of the motor to the cam, and a clutch driven reciprocally by the cam. and a biasing member that biases the operating member in a direction from the top of the cam back to the recess, the operating member being moved from the top of the cam to the recess by driving of the motor. In the process, just before the operating member moves to the bottom of the recess of the cam, transmission of rotational force by the clutch is cut off, and the urging force of the urging member causes the operating member to move to the bottom of the recess of the cam. I'm trying to get it back. Therefore, compared to the case where the operating member is moved to the bottom of the cam by the motor until the end, positional errors such as insufficient or overfeeding of the cam can be reliably prevented.

Configuration of Motor Actuator FIG. 1 shows the configuration of a motor actuator 1. As shown in FIG. A motor 2 serving as its driving source is built into a space formed by a cup-shaped case 3 and a core case 4. And rotor 5 of motor 2
is a permanent magnet, and is rotatably supported by the rotor shaft 6 at the center of the case 3 and by a base plate 7 attached to the opening surface of the core case 4. Note that the case 3 and core case 4 are partially cut and raised so that the rotor 5
Pole teeth 8 are formed at the outer circumferential position, and a rotating magnetic field is generated by the outer excitation coil 9.

A pinion 10 integrated with the rotor shaft 6
is meshed with gear 11 as a gear train for deceleration. This gear 11 is rotatably supported by an intermediate shaft 12 fixed to the core case 4.
The boss 11a is frictionally engaged with the anti-reverse lever 13. When the rotor 5 is reversed due to the frictional rotational force from the gear 11, the reversal prevention lever 13 hits the tip of the reversal prevention pawl 14 formed integrally with the pinion 10. Then, an impact force is applied to the rotor 5 in the forward rotation direction, and the rotor 5 is
is restricted to rotate in the forward direction.

The gear 11 also serves as the clutch plate 16 of one side of the meshing type clutch 15, and the clutch teeth 16a thereof face the clutch teeth 17a of the other clutch plate 17. This other clutch plate 17 is inserted into the intermediate shaft 12 so as to be rotatable and slidable in the axial direction, and is supported by a coil spring 18 provided between this and the clutch plate 16. Therefore, it is always biased in the direction of separation. The hollow shaft 19, which is integral with the clutch plate 17, protrudes outward from the bearing portion 7a of the base plate 7 and is in contact with the tongue piece 20a of the operation plate 20. This operation plate 20 is
At one end, the support part 21a of the mounting plate 21 allows
It is rotatably supported, and the other end is connected by a pin 24 to a plunger 23 of an electromagnetic solenoid 22 fixed to a mounting plate 21.

Furthermore, the clutch plate 17 is inserted inside the gear 25. That is, this gear 25
is engaged with the large teeth of the compound gear 26, and is rotatably supported by the boss 25a on the bearing part 7a of the main plate 7 in a state concentric with the intermediate shaft 12. Integral engagement claw 25b
The engagement hole 17 formed in the clutch plate 17 at the part
b so that it can rotate together with the clutch plate 17.

In this way, the clutch 15 is interposed in a path for transmitting the rotation of the motor 2 to a cam 34, which will be described later.

The compound gear 26 meshes with the large teeth of the compound gear 27 with its small teeth,
Further, the small teeth of this gear 27 mesh with a gear 28 of an output shaft 29. Note that these gears 26 and 27 are rotatably supported by shafts 30 and 31 fixed between core case 4 and base plate 7, respectively. Further, the output shaft 29 is rotatably supported by bearings 32 and 33 fixed to the core case 4 and the base plate 7, respectively.
The tip supports a heart-shaped cam 34 as shown in FIG. This cam 34 is in contact with a roller 36 of an operating member 35. The operating member 35 controls, for example, the drain valve 37a of the controlled device 37, and is always urged by a spring 38 in a direction that contacts the contour of the cam 34.

Here, the spring 38 is connected to the operating member 3 which will be described later.
5 from the top of the cam 34 in the direction of returning it to the recessed portion, and constitutes a biasing member that applies a returning force to the operating member 35.

Configuration of Power Supply Circuit Next, FIG. 3 shows a power supply circuit 39 for the motor 2 and the electromagnetic solenoid 22. motor 2,
and electromagnetic solenoid 22 are connected to power terminals 42 and 41 by switches 40 and 41, respectively.
43 in series. Therefore,
These power supply states can be controlled independently by switches 40 and 41. Note that these switches 40 and 41 are configured as contacts of a mechanical sequence cam or contacts of a relay, and are turned on and off in a predetermined order.

Driving method of the present invention FIG. 4 shows a time chart according to the driving method of the present invention. In this time chart, the controlled device 37 controls the opening and closing of a drain valve 37a of an electric washing machine according to the above embodiment.

As already mentioned, the controlled device 3 to be controlled
7, that is, the drain valve 37a is always urged in the closing direction by the spring 38. At this time, the roller 36 is in contact with the recess 34a of the cam 34, as shown in FIG.

When the drain valve 37a is opened, at a certain time _t1 , before the clutch 15 is set to the engaged state,
The motor 2 is turned into a rotating state by being energized. That is, first, the switch 40 is set to the on state. As a result, the motor 2 is in the no-load state.
It begins to rotate under the starting torque. At this startup, the motor 2 is connected to the controlled device 37 (drain valve 37a).
Since no load has been applied to the motor 2, the hunting phenomenon does not occur in the motor 2, and there is no possibility that the motor 2 cannot be started. Furthermore, since no hunting phenomenon occurs, there is no start delay time, and the safety factor at the start of operation is improved.

Of course, as already mentioned, if the rotation direction of the rotor 5 is in the opposite direction at this starting point, the gear 11 transfers the rotational force in the reverse direction to the reverse prevention lever 1.
3, and its tip is connected to the anti-reverse claw 14.
In order to rotate the rotor 5 to a position corresponding to
The correct rotation direction is regulated by the impact force between the reverse rotation prevention lever 13 and the reverse rotation prevention claw 14. In addition, during this reverse operation, the controlled equipment 3 on the load side
Since the correction operation of the rotational direction of the rotor 5 has already been completed before the rotational force is transmitted to the cam 3
4 is not temporarily reversed, and therefore the accuracy of the stopping position of the cam 34 is improved.

Then, at time _t2 when a predetermined time has elapsed, the switch 41 is turned on, so the clutch plate 17 is pushed by the operation plate 20 and approaches the opposing clutch plate 16, causing the clutch teeth 16a to close. ，
Clutch 15 transmits the rotation of gear 11 to gear 25 by meshing with gear 17a. In this way, the rotation of the rotor shaft 6 is transmitted to the cam 34 via the output shaft 29 while being decelerated by the wheel train. At this time, the roller 36 approaches the top 34b from the concave portion 34a along the heart-shaped contour by constant velocity movement.

When the roller 36 reaches the top 34b, the operating member 35 has been displaced the most against the spring 38, so the drain valve 37a of the controlled device 37 is in an open state. At this time _t3 , switch 40 is set to the off state. However, since the switch 41 is still in the energized state, a small static torque of the rotor 5 is acting on the input side of the wheel train, that is, the rotor shaft 6, due to the engaged state of the clutch 15. The shaft 29 receives a component force in the direction of reverse rotation from the operating member 35 and the roller 36, but is set in a state in which it does not rotate in reverse. Therefore, as long as the electromagnetic solenoid 22 is energized, even if the motor 2 is de-energized,
The controlled device 37, that is, the drain valve 37a remains open. The energization time (t ₁ → t ₃ ) of the motor 2 is determined from the time t ₂ when the electromagnetic solenoid 22 is turned on, or from the time t ₁ when the motor 2 is energized, using an electrical timer circuit or a sequence cam. , is set by regulating a predetermined time.

Note that when the drain valve 37a is in the open state, the roller 36 is moved toward the top 34 as shown in FIG.
It touches the outline of the cam 34 slightly past the apex of b.

Thereafter, when the drain valve 37a is closed again, the motor 2 is turned on by the switch 40 at a certain time point _t4 while the electromagnetic solenoid 22 remains energized. As a result, the cam 34 is again driven in the same rotational direction by the motor 2, so that the roller 36 of the operating member 35 is rotated at the top 34b.
It moves in the direction approaching the concave portion 34a. In this way, the drain valve 37a is biased by the spring 38 and operates in the closing direction along the contour of the heart-shaped cam 34 in synchronization with its rotation. Therefore, in this process, the drain valve 37a
The door will not close suddenly, and no impact noise will be generated at that time.

At time _t6 when a predetermined time has elapsed, the switch 40 is turned off, so the motor 2 automatically stops.

Before this motor 2 stops, the switch 41
As a result, the electromagnetic solenoid 22 is set to the OFF state. Therefore, at the time t ₅ , the clutch 15
cuts off the transmission of rotational force in the wheel train. At this point, the motor 2 continues to rotate under no load in order to forcefully separate the clutch plates 16 and 17, and stops after a predetermined delay time (t ₅ →t ₆ ). become.

At the time _t5 when clutch 15 is disengaged, gear 2
5, 26, 27, and 28 are no longer affected by the rotational force from the motor 2 side, and are in a state where they can rotate with a predetermined torque when viewed from the output shaft 29 side, so the spring 38 becomes the driving force, and cam 34
In order to forcibly rotate the drain valves 37a in the same direction, the drain valve 37a moves in the direction of self-closing due to the force of the spring 38. Furthermore, at this time as well, there is no impactful return, but rather, the cam 34 is rotated slowly and with a small stroke, so almost no impact noise is generated.

For this operation, the angle between the axis of the operating member 35 and the normal at the point of contact with the cam 34, that is, the pressure angle, is set within a range that allows the spring 38 to rotate the cam 34. In other words, the return force of the drain valve 37a, that is, the tangential force generated by the elasticity of the spring 38 at the contour portion of the cam 34 rotates the gears 25, 26, 27, and 28 while driving them at an increased speed. It has to be something you can get.

When there is a power outage or an emergency stop is required while the drain valve 37a is open, the force of the spring 38 is such that the heart-shaped cam 34 can be forcibly rotated together with the gears 26, 27, and 28. naturally returns to the operation start position, that is, the position of the recess 34a. Of course, such a natural return operation cannot be performed if the roller 36 is at the apex of the cam 34, since the cam 34 cannot rotate in any direction. It is something that will be done. In addition, drain valve 3
In the process of 7a moving from the closed state to the open state,
The control device 37 is set to an inactive state as necessary to prevent danger.

In this way, the cam 34 has the recess 34a and the top 34b.
During the movement of the operating member 35 from the top 34b to the recess 34a, the electromagnetic solenoid 22 is turned off, and then the operating member 35
The self-returning force of the roller 36 of the operating member 35
falls to the bottom of the recess 34a of the cam 34 and stops at that position, so the error in the stopping position of the cam 34 when the motor 2 drives the cam 34 to the end can be eliminated. Of course, even if the operating member 35 passes the recess 34a and approaches the next heart-shaped outline, it is forcibly returned in the opposite direction, so no position error occurs in this case either.

Note that the clutch 15 is equipped with an electromagnetic solenoid 22.
In addition, the controlled device 37 is not limited to the drain valve 37a as in the embodiment, but may be a shutter of a ventilation fan or a damper of a refrigerator. Further, the cam 34 can also be configured as a half-heart-shaped cam, as shown by the dashed line in FIG.

Effects of the Invention In the present invention, when the operating member of a controlled device returns, the heart-shaped cam is driven by the rotational force of the motor, and the operating member moves from the top of the cam, that is, the temporary stop position, to the lower part, that is, the operation start position. Since the controlled device moves to just before , there is no impact when the controlled device returns, and the impact noise is also reduced, compared to the conventional example in which the control member returns naturally using the coil spring itself. Also, in the event that a power outage or emergency shutdown becomes necessary during the recovery process,
The return force from the biasing member of the operating member automatically rotates the cam to the predetermined operation start position (bottom of the recess).
Therefore, subsequent necessary operations can always be started from the point at which the operation started.

In particular, the invention provides that the clutch is set to the OFF state just before the operating member reaches the bottom of the recess;
After the rotation transmission path from the motor to the cam is cut off, the operating member reaches the bottom of the recess of the cam by the return force of the biasing member, and remains stable at the most stable position of the recess, that is, at the bottom. Since the motor stops, it is possible to reliably prevent over-feeding or under-feeding of the cam compared to when the motor drives the cam all the way to the end. Therefore, when the motor is subsequently started, the actuating member always starts from the lower part of the recess of the cam, thereby ensuring the necessary movement.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along the gear train of the motor actuator, FIG. 2 is a plan view of the cam, FIG. 3 is a circuit diagram of the power supply circuit, and FIG. 4 is a time chart. 1...Motor actuator, 2...Motor,
5... Rotor, 10... Pinion, 11... Gear, 15... Clutch, 20... Operation plate,
22... Electromagnetic solenoid, 26, 27, 28...
Gear, 34...Cam, 35...Operation member, 37...
...Controlled equipment, 38...Spring, 39...Power supply circuit, 40, 41...Switch.

Claims (1)

[Claims] 1. A motor, a full or half heart-shaped cam driven by the motor, and a clutch interposed in a path for transmitting the rotation of the motor to the cam;
A motor actuator having an operating member that is reciprocated by the cam, and an urging member that urges the operating member in a direction from the top of the cam back to the recess, the operating member being moved from the top of the cam to the recess. During the movement process driven by the motor, just before the operating member moves to the bottom of the recess of the cam, transmission of rotational force by the clutch is cut off, and the urging force of the urging member causes the operating member to move. A method for driving a motor actuator, characterized by returning the cam to the bottom of a recess.