JP4309603B2 - Actuator - Google Patents

Description

[0001]
【Technical field】
The present invention relates to a motor-driven actuator.
[0002]
[Prior art and its problems]
As a motor-driven actuator, an actuator arm that can move forward and backward, a motor that drives the actuator arm to rotate in either forward or reverse direction, and when the energization of the motor is stopped, There is known a type having spring means for moving the spring. This actuator is used, for example, as an actuator of a vehicle door lock mechanism, and releases the lock mechanism by movement of an actuator arm when the motor is energized. When the energization of the motor is released, the actuator arm is restored by the force of the spring means. At the time of this restoration, the following problem occurs.
[0003]
That is, when the circuit including the motor is an open circuit when the motor is de-energized, the rotation of the motor is free, and the actuator arm is suddenly restored by the force of the spring means, and other members (stopper members) ) Will cause a loud collision sound. On the other hand, if the circuit including the motor is closed when the motor is de-energized, a counter electromotive force is generated when the rotational force is applied to the motor via the actuator arm that is restored by the spring force. Try to turn in the direction against the force). Therefore, the return of the actuator arm is delayed as compared with the case where an open circuit is used. When the return of the actuator arm is delayed, the door cannot be locked in the following cases.
[0004]
For example, suppose that the motor of the actuator is rotated in the unlocking direction via the switch means to release the locking mechanism, and the motor is immediately de-energized. Then, although the vehicle door lock is released, when the opened door is closed immediately after that, the actuator arm may not yet return. At this time, the door cannot be locked.
[0005]
OBJECT OF THE INVENTION
An object of the present invention is to obtain a motor-driven spring force return actuator capable of setting the return speed of an actuator arm that is returned by a spring force to an appropriate speed based on the above problem awareness of the conventional actuator.
[0006]
Summary of the Invention
The present invention includes an actuator arm that can be moved forward and backward, a motor that rotationally drives the actuator arm in either the forward or reverse direction, and the motor and the actuator arm that are connected to the other of the forward and reverse sides when energization of the motor is stopped. In the actuator arm having the spring means to be moved to the motor, switch means for controlling energization / non-energization to the motor in the motor drive circuit, and power supply to the motor when the motor is de-energized by the switch means A closed circuit formed between the terminals, and in this closed circuit, the current direction when the motor is energized is the forward direction, and when the motor is not energized, the current direction when the motor is energized by reverse rotation of the motor A single diode that absorbs the current generated in the same direction as the It is characterized in that to control the braking force applied to.
According to this configuration, by selecting the characteristics of the PN junction element inserted in the closed circuit, an appropriate braking force is applied to the motor when it is not energized. Speed.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4 show a mechanical configuration of a lock mechanism of a vehicle tailgate door to which an actuator of the present invention is applied. As shown in FIG. 1, a tailgate (vehicle door) 13 is pivotally attached to an upper end portion of a rear opening 11 of a van type vehicle body 10 by a pivot shaft 12 in the vehicle left-right direction. A tailgate striker (striker) 14 is fixed to the lower end portion of the rear opening 11, and a tailgate lock mechanism (locking mechanism) that holds and releases the striker 14 at the lower end portion (free end portion) of the rear opening 11. 20 is provided.
[0008]
2 and 3 show a basic configuration of the lock mechanism 20. A hook 22 and a ratchet 23 are pivotally attached to the base plate 21 having the striker entry groove 21a into which the striker 14 enters, by shafts 22a and 23a located on both sides of the striker entry groove 21a. The hook 22 includes a gripping groove 22b that grips the striker 14, and when the striker 14 enters the striker entry groove 21a, the striker 14 is received in the gripping groove 22b and rotates about the shaft 22a. The ratchet 23 has a lock portion 23b that engages with the locking surface 22c of the hook 22 rotated by the striker 14 in this way. When the lock portion 23b engages with the locking surface 22c, the hook 22 Is held in the locked position. The hook 22 is urged to rotate in a direction to open the striker 14 by a torsion spring 22d, and the ratchet 23 is urged to rotate in a direction in which the lock portion 23b is engaged with the locking surface 22c by the torsion spring 23d. Yes.
[0009]
An intermediate lever 24 is pivotally attached to the base plate 21 by another shaft 24a. One arm 24 b of the intermediate lever 24 is engaged with the ratchet 23, and a pin 24 d implanted in the other arm 24 c is engaged with the actuator arm 31 of the actuator 30. The intermediate lever 24 is urged in a direction away from the ratchet 23 by a torsion spring 24f, and the rotation urging end is regulated by a stopper 24g. In a state where the hook 22 is gripping the striker 14 (a state where the lock portion 23b of the ratchet 23 is engaged with the engaging surface 22c of the hook 22), the intermediate lever 24 is opposed to the torsion spring 24f as shown in FIG. When the ratchet 23 is rotated in the clockwise direction (unlock direction), the ratchet 23 is rotated in the counterclockwise direction (unlock direction), and the engagement between the lock portion 23b and the locking surface 22c is released. As a result, the hook 22 rotates in the direction to open the striker 14 by the force of the torsion spring 22d, and the lock mechanism 20 is unlocked, so that the tailgate 13 can be opened.
[0010]
The actuator 30 (actuator arm 31) has a function of imparting a rotational movement in the unlocking direction to the intermediate lever 24 against the force of the torsion spring 24f. The rotational movement in the unlocking direction with respect to the ratchet 23 can be given by a key cylinder or other mechanism in addition to the actuator 30, but the present embodiment is characterized by the actuator 30. Illustration of the mechanism is omitted.
[0011]
As shown in FIG. 4, the actuator 30 includes a drive motor 33, a worm wheel 34 pivotally attached to a shaft 34a, and a sector gear 35 pivotally attached to a shaft 35a. A worm 33 a fixed to the output shaft of the drive motor 33 meshes with the worm wheel 34, and a gear 34 b fixed coaxially to the worm wheel 34 meshes with the sector gear 35. The above-described actuator arm 31 engaged with the intermediate lever 24 is fixed to the shaft 35 a and rotates integrally with the sector gear 35. The drive motor 33 is a direct current motor that rotates (only) in a predetermined direction when energized. The rotation of the drive motor 33 causes the worm 33a, worm wheel 34, gear 34b, and sector gear 35 to pass through. As a result, the actuator arm 31 rotates in the unlocking direction (counterclockwise in FIGS. 3 and 4, on-direction). On the other hand, the sector gear 35 is coaxially provided with a torsion spring 35b that urges the sector gear 35 (actuator arm 31) to rotate in the direction opposite to the unlocking direction, and when the drive motor 33 is de-energized. The drive motor 33 is rotated in the direction opposite to that during energization by the spring force of the torsion spring 35b (and the spring force of the torsion spring 24f). The speed reduction mechanism from the worm 33a to the sector gear 35 is a speed reduction mechanism that allows this reverse rotation.
[0012]
In this embodiment, the power supply terminals 33a and 33b of the drive motor 33 are short-circuited and closed when the energization is canceled so that the return speed of the actuator arm 31 (drive motor 33) when the energization to the drive motor 33 is released becomes appropriate. The circuit is characterized in that a PN junction element, for example, a diode, having a forward current direction when energized is inserted in the closed circuit.
[0013]
5 to 7 show an embodiment of a drive circuit including the drive motor 33. FIG. 5 to 7, the actuator 30 and its switch circuit 40 are shown as separate blocks. The switch circuit 40 includes a switch 41 that is turned on and off. When the switch 41 is on, the DC power supply 42 and the drive motor 33 are connected, and the drive current from the DC power supply 42 is applied to the motor 33. . On the other hand, when the switch 41 is off, the connection between the drive motor 33 and the DC power source 42 is cut off, and both power supply terminals 33a and 33b of the drive motor 33 are short-circuited to form a closed circuit. The switch 41 (switch circuit 40) is provided in the tailgate 13 as shown in FIG. 2, for example.
[0014]
In this closed circuit, a diode 50 is inserted in such a direction that the current direction during energization is the forward direction. 5 to 7 show variations of the position where the diode 50 is inserted. In FIG. 5, the diode 50 is inserted in the actuator 30, and in FIG. A diode 50 is provided on the OFF terminal side of 41, and in FIG. 7, the diode 50 is provided in a harness (connection) 43 that connects the actuator 30 and the switch circuit 40. In the embodiment of FIG. 4, a diode 50 is provided in the harness 43.
[0015]
According to the actuator 30 having the above-described configuration, the lock mechanism 20 can be operated as follows. When the switch 41 of the switch circuit 40 is turned on in the locked state of the lock mechanism 20, the direct current 42 and the drive motor 33 are directly connected. That is, power is supplied from the DC power source 42 to the drive motor 33 via the diode 50. Then, the drive motor 33 rotates the actuator arm 31 in the unlocking direction (counterclockwise direction in FIGS. 3 and 4, the on direction) via the worm 33 a, worm wheel 34, gear 34 b, and sector gear 35. When the actuator arm 31 pivots in the unlocking direction, the intermediate lever 24 pivots in the unlocking direction against the torsion spring 24f, and the ratchet 23 pivots in the unlocking direction to lock the locking portion 23b and the locking surface 22c. Is released, the hook 22 opens the striker 14 by the force of the torsion spring 22d, and the lock mechanism 20 is unlocked.
[0016]
When the switch 41 is turned off, the power supply to the drive motor 30 is cut off, and at the same time, a closed circuit that short-circuits the power supply terminals 33a and 33b of the motor 33 is configured. Then, the actuator arm 31 is rotated in a direction opposite to that during energization by the spring force of the torsion spring 35 and the torsion spring 24f. Accordingly, the drive motor 33 rotates in the direction opposite to that when energized, and as a result, the drive motor 33 generates a current in the same direction as when energized . However, since the generated current is absorbed by the diode 50, an appropriate braking force can be applied to the drive motor 33. That is, the return speed of the drive motor 22 can be set as appropriate according to the characteristics of the diode 50 inserted in the closed circuit. Thus, even when the tailgate 13 is closed immediately after the lock is released, it is possible to prevent a situation in which the door lock becomes impossible, and no large operation noise is generated when the drive motor 33 is returned. The diode 50 (PN junction element) only needs to have a low resistance with respect to the current direction during energization and a high resistance with respect to the direction opposite to the current direction during energization.
[0017]
As described above, in the present embodiment, since the diode 50 is inserted in the closed circuit in a direction in which the current direction during energization is the forward direction, an appropriate braking force can be applied to the drive motor 33 when energization is released. The diode 50 is preferably incorporated in the drive motor 33 (actuator) for the purpose of improving theft resistance. Even when the diode 50 is inserted outside the drive motor 33, it can be inserted as close to the drive motor 33 as possible. desirable.
[0018]
In the illustrated embodiment, the present invention is applied to an actuator in which the actuator arm 31 swings around a shaft 35a. However, the rotation of the drive motor 33 is reciprocated by a known mechanism such as a rack and pinion mechanism. The present invention can be similarly applied to an actuator that converts motion.
[0019]
【The invention's effect】
According to the present invention, it is possible to obtain a motor-driven spring force return actuator that can set the return speed of an actuator arm that is returned by a spring force to an appropriate speed.
[Brief description of the drawings]
FIG. 1 is a perspective view of a vehicle showing an embodiment of a vehicle door (tailgate) having an actuator according to the present invention as viewed from the rear.
2 is a cross-sectional view taken along line II-II in FIG.
FIG. 3 is a view taken along the line III-III in FIG. 2;
4 is a partially exploded front view showing a configuration example of an actuator in FIG. 3. FIG.
FIG. 5 is a circuit diagram showing an embodiment of an actuator according to the present invention.
FIG. 6 is a circuit diagram showing another embodiment.
FIG. 7 is a circuit diagram showing still another embodiment.
[Explanation of symbols]
10 Vehicle Body 11 Rear Opening 12 Axis 13 Tail Gate (Vehicle Door)
14 striker 20 tail gate lock mechanism 21 base plate 21a striker entry groove 22 hook 23 ratchet 24 intermediate lever 30 actuator 31 actuator arm 32 housing 33 drive motor 33a worm 34 worm wheel 35 sector gear 35b torsion spring 40 switch circuit 41 switch 42 DC power supply 50 diode

Claims (2)

An actuator arm that can move forward and backward, a motor that rotationally drives the actuator arm in either the forward or reverse direction, and a spring that moves the motor and the actuator arm to the other of the forward and reverse directions when energization of the motor is stopped An actuator arm having means,
In the motor drive circuit, there is provided switch means for controlling energization / non-energization to the motor, and a closed circuit formed between power supply terminals to the motor when the switch means is not energized to the motor,
In this closed circuit, the current direction when the motor is energized is the forward direction, and when the motor is not energized, a diode that absorbs current generated in the same direction as the current direction when the motor is energized by reverse rotation of the motor is interposed Let
An actuator characterized in that the braking force applied to the motor when the motor is not energized is controlled only by this diode . 2. The actuator according to claim 1, wherein the actuator arm reciprocates forward and backward about an axis.

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