JP2712779B2 - Ultrasonic motor device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to an ultrasonic motor device for driving internal and external equipment such as a door mirror of an automobile.

(Prior Art) As an ultrasonic motor device, there is, for example, one shown in a piezoelectric element of a surface acoustic wave motor disclosed in Japanese Patent Application Laid-Open No. 60-22480.

Such a conventional general ultrasonic motor applies a voltage of a different frequency to an ultrasonic vibrator (stator) configured by fixing a piezoelectric body to an elastic body by detecting its distortion state, that is, vibration, The rotor, which is pressed against the stator by applying progressive vibration thereto, that is, the moving body is moved to drive a fixture device such as a door mirror, and the resonance state when the motor is driven is automatically tracked and driven.

(Problems to be Solved by the Invention) However, such a conventional ultrasonic motor device simply detects the distortion state of the piezoelectric body when the motor is driven and automatically tracks the resonance state of the motor. Therefore, if a torque greater than the holding torque is applied between the rotor and the stator due to an external force applied to the mirror or the like when the motor is not driven, the sliding surfaces are worn and the durability of the motor is impaired. Or, it produces an unpleasant sound due to slip. There was a problem.

The present invention solves the above problems by providing an ultrasonic motor device that significantly reduces wear generated between a rotor and a stator due to an external force when the motor is not driven, and that does not generate unpleasant noise due to slippage. It is intended to solve.

[Constitution of the Invention] (Means for Solving the Problems) In order to achieve the above object, according to the present invention, an ultrasonic transducer in which a plurality of electrostrictive elements are fixed to an elastic body is brought into pressure contact with the elastic body. A moving body, a first circuit device and a second circuit device that generate vibrations of frequencies different in phase from each other in time in the electrostrictive element, detecting means for detecting vibration of the vibrator, and driving the moving body When the first circuit device and the second circuit device are both driven at the time of driving, and when the vibration of the vibrator is detected by the detection means when the moving body is not driven, the first circuit device and the second circuit device are driven. And a control device for driving one or both of the circuit devices described above, and an equipment device such as a door mirror connected to the moving body.

(Operation) For example, if the door mirror or the like hits an external human arm or the like and moves forward or backward while the motor is not operated and is stationary, a slip occurs between the rotor and the stator of the motor. The vibration based on the slip is detected by the detection means and an output is generated to the control means. When the control means outputs to both the first and second circuit devices by this output,
Because the rotor vibrates in that direction due to progressive vibration,
Wear of the sliding surface can be reduced. Also, no unpleasant sound is generated. Further, when the control means outputs to one of the first and second circuit devices, the contact area of the sliding surface is reduced by the standing wave vibration, so that the wear of the sliding surface can be similarly reduced, and There is no pleasure.

Hereinafter, the present invention will be described with reference to the drawings. Fig. 1 ~
FIG. 8 is a view showing an embodiment of the invention to which a door mirror is applied.

First, the structure will be described with reference to FIG. 3 in a front view and FIG. 4 in a top view. The base 10 is attached to a door and supports a flapper (door mirror body) 40. On this base 10,
Plate 20 is fixed with screws 10a. The center shaft 30 is press-fitted into the plate 20 and is detented on the plate 20, so that even if a torque is applied around the shaft, the center shaft 30 does not rotate.

Further, the mount bracket 50 is fixed to the mirror flapper 40 with screws (the flapper 40 and the bracket 50 may be integral parts), and the joint gear 70 is passed through the joint shaft 60 (with the terminal gear 31). A bearing 80 is incorporated between the end of the joint shaft 60 (upper side in the figure) and the mount bracket 50. Further, a cap 90 is pressed against the other end portion (the lower part in the figure) of the joint shaft 60, and the pressing force can be adjusted by a ball plunger 91 in the cap 90. The ball plunger 91 is adjusted so that the joint shaft 60 has low sliding resistance. The center shaft 30 is passed through a center shaft hole of an assembly part (integral part in FIG. 3) of the mirror flapper 40 and the mount bracket 50 described above,
Further, a center gear (gear) 110 to which the limit switch 101 is fixed is also penetrated. However, the center gear 110 is fixed to the center shaft 30 and further meshes sufficiently with the gear portion (planetary gear) 31 of the joint shaft 60.

The limit switch 101 is mounted on the mounting bracket 59.
It is fixed to.

Here, the limit switch 101 is shown in FIGS.
As shown in FIG. 3C, the circuit comprises a closing operation terminal 25, a closing operation pattern section 39, an opening operation terminal 26, and an opening operation pattern section 38.

The motor gear 130 is fixed to the shaft of the ultrasonic motor 120. The gear 130 is designed to mesh with the joint gear 70. In this state, the ultrasonic motor 120 is mounted on the mounting bracket 5
It is fixed on the upper surface of the “0” with the screw 120a. Hole 4 of mirror flapper 40
At 1a, fix the mirror cover 140 with screws, and remove all the assembly parts (except for the base 10) as described above.
Inside.

In addition, as for the structure, only the left side of the vehicle has been described above, but the right and left sides may be made differently on the right side. In the present embodiment, the limit switch 10
Although the terminals 25 and 26 of the 1 move, the pattern units 38 and 39 may move. The above-mentioned switch may be any other switch that can detect the position of the door mirror.

The base 10, the mirror body 40, and the cover 140 constitute a door mirror device 190.

As shown in FIG. 1, a detailed structure of the ultrasonic motor 120 is entirely protected on the upper side by a case 41, and the lower side of the bracket 50 in contact with the first arm 11 is closed by a substrate 63. It is configured such that water, oil, dust and the like do not easily enter, thereby preventing torque reduction and key noise. The drive shaft 19 is provided at the center of the ultrasonic motor 120, and is supported by a ball plunger 47 via a disc spring 43 and a bush 45 at the upper end of the drive shaft 19. A rotor 49 is mounted near the upper end of the drive shaft 19, and a substantially center of an upper surface of the rotor 49 is supported by the disc spring 43 via a rubber 51. The lower side of the peripheral portion of the rotor 49 is pressed against the elastic body 53, and a piezoelectric body (electrostrictive element) 55 is provided below the elastic body 53. The elastic body 53 and the piezoelectric element 55 constitute an ultrasonic transducer (stator) 53a.
A radial bearing 59 is provided below the inner peripheral portion of the elastic body 53 near the drive shaft 19, and the middle of the elastic body 53 is fixed to the substrate 63 by screws 57. Also, case 41
A mode 61 for electric wiring is inserted into the ultrasonic motor 120 through the space between the substrate and the board 63, and an operation signal is supplied to the ultrasonic motor 120 via the cord. The drive shaft 19 is fitted and fixed to the motor gear 130, and the joint gear 7
Transmit the driving force to 0.

The ball plunger 47, which supports the upper end of the drive shaft 19, adjusts the pressing force, thereby controlling the ultrasonic motor 120.
Is to adjust the output torque. FIG. 5 is a graph showing the relationship between the output torque and the applied pressure adjusted by the ball plunger 47. As shown in FIG. It can be easily set in the pressure adjustment range. By configuring the output torque with the ball plunger 47 in this manner, the workability of the adjustment can be improved and the performance can be stabilized.

FIG. 2 is a drive control circuit of the ultrasonic motor 120.
As shown in the figure, the piezoelectric body 55 of the ultrasonic motor 120 is divided into four parts, 55a, 55b, 55s, and 55g, and the sine wave drive signal and the sine wave drive signal are transmitted from two opposing transformers 71 and 72. The cosine wave signal having a 90 ° phase difference with respect to the
a, 55b, and the drive shaft 19 of the ultrasonic motor 120 rotates. In addition, the operation SW signal E
8 outputs a positive / inverted signal. If the opening / closing reverse signal of the operation SW signal is input, a sign in which the opposite of the above-mentioned positive and cosine is reversed is supplied from the transformers 71 and 72 to the dividing portions 55a and 55b of the piezoelectric body 55. , The drive shaft 19 rotates in the opposite direction.

In the circuit device 1, a circuit including the truss 71 for generating a sine wave signal is referred to as a first circuit device, and a circuit including a transformer 72 for generating a cosine signal is referred to as a second circuit device.

Here, 55s constitutes a polarization, that is, a motor electrode (detection means) capable of detecting the vibration state of the piezoelectric body 55, that is, the S-phase vibration in the strain state, as an output. Electrodes. Reference numeral 78a denotes control means provided in the CPU 78. The control means 78a receives the operation switch signal E, the door mirror open / closed state detection signal F, and the F / B signal G when the motor of the piezoelectric body 55s is operated or the slip detection signal H when the motor is not operated.
The control signal is generated together with the CPU 78.

In the figure, 73 is a power transistor, 74 is a ring counter for generating a divide-by-4 forward / reverse signal, 75 is a voltage controlled oscillator,
76 is a D / A converter, 152 is an A / D converter, and 153 is a rectifier.

The back side of the motor 120 in FIG. 2 is grounded over the entire surface.

Next, the operation of the above embodiment will be described with reference to FIGS. 7 (a), (b) and (c).

(A): During normal operation: FIG. 7 (b) is a diagram showing a mirror flapper, that is, a state in which the door mirror body 40 is open (functioning as a mirror). In this open state, when a close switch (not shown) is operated, a drive signal for closing is supplied to the ultrasonic motor 120 via the closing operation terminal 25 of the limit switch 101 and the closing operation pattern section 39, whereby The drive shaft 19 of the ultrasonic motor 120 rotates clockwise in FIG. 7B. This rotation is from the drive shaft 19 to the motor gear.
130, the joint gear 70, and the joint shaft 60 are transmitted to the planetary gear 31 so that the planetary gear 31 tries to rotate in the counterclockwise direction.
, The planetary gear 31 cannot rotate the center gear 110, and revolves around the center gear 110 in a counterclockwise direction by the reaction force.
7A, the mirror flapper, that is, the door mirror body 40 is closed (retracted) as shown in FIG.

In the closed state of FIG. 7A, an open switch (not shown) is operated, and an open / close drive signal is supplied to the ultrasonic motor 120 via the open operation terminal 26 of the limit switch 101 and the open operation pattern section 38. Then, the ultrasonic motor 120
The drive shaft 19 rotates counterclockwise in the opposite direction. This rotation also causes the planetary gear 31 to rotate in the clockwise direction, but revolves clockwise around the center gear 110 due to the reaction force from the fixed center gear 110, causing the seventh gear to rotate.
The position shown in FIG. 7A is moved to the position shown in FIG. 7B, whereby the mirror flapper door mirror body 40 is opened.

(B) At the time of external force operation: Next, an operation when the mirror flapper 40 of the electric folding door mirror moves rearward or forward by hitting, for example, a human arm or another object, will be described.

As shown in FIG. 7 (b), when an object collides with the mirror flapper 40 and an external force acts on the mirror flapper 40 as shown by an arrow 99 in a state where the mirror flapper 40 is open, the center of the mirror flapper 40 is A force that rotates clockwise around the shaft 30 acts. As a result, the planetary gear 31 revolves clockwise around the center gear 110 while rotating in the counterclockwise direction, and attempts to move to the position shown in FIG. 7A. During this movement, joint shaft 60 rotates counterclockwise with planetary gear 31 rotating counterclockwise, and joint gear 70 also rotates counterclockwise. Joint gear
When 70 rotates counterclockwise, motor gear 130 meshing with joint gear 79 tends to rotate clockwise. In this case, if the rotational force is small, the motor gear 130
Since the stator 53a composed of the elastic body 53 and the piezoelectric body 55 is held in pressure contact with the rotor 49 in the ultrasonic motor 120 connected via the drive shaft 19, the motor gear 1
30 does not rotate, but when the rotational force of the motor gear 130 exceeds a predetermined value, the sliding surface between the rotor 49 and the stator 53a of the ultrasonic motor 120 slips, and the holding between them is released, and the ultrasonic motor 120 Rotor 49 rotates. As a result, the mirror flapper 40 changes from the state of FIG. 7 (b) to the state of FIG. 7 (c). Conversely, when an object collides from the direction opposite to the arrow 99, a force opposite to that described above is applied, and the ultrasonic motor 120
Rotor 49 rotates similarly. As a result of this collision, the mirror flapper 40 is closed as shown in FIG.

When the mirror receives a force from the closed state to the open side by such an external force action in the direction of arrow 99 or the opposite direction, or
When a force is applied in the closing direction from the over-open state or the open state, in the former case, the opening operation terminal 26 and the pattern section 38
In the latter case, the motor is driven to the closed state by the contact between the closing operation terminal 25 and the pattern portion 39.

That is, since the motor is spontaneously operated and rotated in the direction of the external force, abrasion occurs on the sliding surface between the stator and the rotor of the motor, so that no abnormal noise is generated.

In the above embodiment, only the left side of the electric door mirror is shown, but the right side can be similarly configured by creating each part with a right and left difference. Although the limit switch 101 is configured so that its terminals 25 and 26 move, it can be configured so that the pattern sections 39 and 39 move. Further, the limit switch 101 may be any switch as long as the position of the door mirror can be detected.

Further, as described above, when the motor 120 is not operated, the mirror wrapper 40 receives a strong external force, for example, manually from the arrow 99 or from the opposite direction, and slides between the rotor 49 and the stator 53 in the ultrasonic motor 120. The surface slips sixth
As shown in the figure, a sine wave of about 100 kHz is generated from the piezoelectric body 55s, and the output can detect that the rotor 49 has rotated.

That is, as shown in FIG. 2, the control means 78a of the CPU 78 inputs a slip detection signal H at the time of non-operation together with the F / B signal G at the time of operation and a signal from the electrode 55s. The circuit device 1 is operated by the input of both signals of the door mirror open / close state signal F and the motor 120 is driven.

Further, when vibration is detected when the ultrasonic motor 120 is not operating, the control means 78a outputs the signal to one of the first circuit device and the second circuit device of the circuit device 1 to output a sine wave or a cosine wave. The output may be such that (standing wave) vibration is generated in the elastic body (stator) 53. In this case the rotor
Surface waves are generated on the sliding surface with the surface 49, and the area of the contact portion is reduced accordingly, so that the occurrence of wear and abnormal noise can be reduced.

As described above, in the embodiment of the present invention, by using the components of the ultrasonic motor as it is, the ultrasonic motor in a non-operation state when receiving an external force is operated, and the wear of the sliding surface and the generation of abnormal noise are reduced. This is characterized in that it can be prevented, and this can be achieved with a low cost and a simple configuration.

In the above embodiment, the slip vibration detection is performed by the electrode 55S. However, the slip vibration may be detected by another external detection unit.

FIG. 8 is a flowchart for detecting a manual slip when the ultrasonic motor is not operating as described above and rotating the door mirror. This will be described. First, the position of the mirror flapper is detected (step 200). It can be seen that this position detection is turned ON / OFF depending on whether or not the terminal 26 and the pattern portion 38 in FIG. 7 are in contact with each other. Thereby, it can be determined with respect to FIGS. 7A and 7B. In this embodiment, (b) and (c)
Cannot be determined, but there is no problem. The motor driving direction is determined by this, but (b) and (c) do not need to be determined because they are in the same direction.

If the terminal 26 and the pattern portion 38 are not in contact (OFF), the process proceeds from step 201 to 210. If contact (ON), go to 220. In step 210, if the frequency signal due to slip comes from the (door mirror open state), the CPU determines that a force for manual storage is acting, and drives the door mirror by motor in the closing direction (step 21).
1). Otherwise, it is only necessary to loop in step 210. The process proceeds from step 211 to step 212. If the door mirror is closed (the terminal 25 and the pattern unit 39 are turned off), the motor stops in step 213. Otherwise, 120 will continue to drive until the door mirror closes. Also, as described above, when the process proceeds to step 220 by step 201, the process similarly proceeds to step 213 at last. Although not shown in the present embodiment even within the loop of FIG. 8, when the operation SW operated by the operator is operated,
After exiting from this loop, the ultrasonic motor 120 is turned forward or reverse according to the operation switch so that normal operation is performed.

In FIG. 8 showing this flow, a frequency signal generated from the piezoelectric body 55s is used as the slip detection signal, but a voltage signal of usually 5 V or more can be used depending on the slip speed in the ultrasonic motor 120.

As described above, in an electric door mirror device using an ultrasonic motor, when a mirror hits a person or another obstacle, the rotor of the motor is instantaneously hit.
A slip between the stators is detected and a traveling wave or a standing wave is generated in the stators to drive the motor to easily rotate the mirror in the direction of the external force. In addition to reducing the impact of people or other obstacles or the impact of the door mirror body,
Safety can be improved.

 9 to 11 show another embodiment.

This embodiment is applied to an electric sun visor. To explain the configuration, a sun visor body 203 is supported by a sun visor support rail 201 and a sun visor drive rail 202, and a slider 204 that slides in the drive rail 202 at the center of the sun visor body 203 is fixed to the sun visor body 203 by a ring 205. I have.

A wire 206 is connected to the slider 204. A motor 207 is fixed between the ceiling lining 208 and the roof panel 209 to move the wire 206 back and forth. In the figure, reference numeral 210 denotes a front window.

FIG. 10 is a view in the direction of arrow A (side view) of FIG.
FIG. 11 shows these separately.

In addition, the front end of the sun visor 203a is
By retracting the windshield upper garnish 211
It is possible to fill the gap between the slide openings and prevent the sun visor 203a from rattling.

When the sun visor 203a is manually pulled out, it becomes a projection for catching by hand. In addition, as shown in FIGS. 13 and 14, a pantograph 212 is built in the sun visor body 203c so that the bellows 213 can be extended and retracted, and when retracted, the wire 206 can be retracted even when stretched by pulling the wire 206 with the motor 207. Becomes With this structure, it can be made effective when light-shielding properties are required.

 Next, the operation of this embodiment will be described.

In the retracted state of the sun visor 203, the motor 206 is rotated to push the wire 206 forward, and the slider 204 is moved forward. When the slider 204 moves in the drive rail 202, the sun visor body 203 projects forward, and the slider 2
When 04 moves forward from the point A, the sun visor body 203 rotates toward the driver and descends. That is, it swings down to block the sun rays. In the case of storing, when the motor 206 is rotated in the reverse direction, the sun visor 203 stores the data in the reverse operation.

Next, the application of the main body to the electric sun visor shown in FIGS. 9 to 14 will be described. As in the case of the door mirror, the opening and closing of the sun visor may be performed by the operation switch as shown in FIG. The ultrasonic motor 207 is operated by turning ON / OFF the operation SW, and the sun visors 203, 203a, 203c are opened and closed. When the motor 207 is not operated, the operation can be performed in the same manner as in FIG. 8 of the flowchart. That is, the mirror is replaced with a sun visor to detect the position of the sun visor, and similarly, the slip detection of the sun visor is manually performed by the electrode 55c in FIG. 2, and the steps in the flow shown in FIG. 8 may be followed. For detecting the position of the sun visor, for example, a limit switch for detecting lock may be provided in the sun visor drive rail 202.

Next, FIGS. 15 (a), (b) and (c) show examples of application to an electric sun visor with a side visor. (A) is a view as viewed from obliquely above, (b) is a view as viewed from above in the vehicle body,
(C) is a sectional view taken along the line CC of (b).

The side visor 302 is attached to the back surface of the slide sun visor 301, and two protrusions 303 are attached to the slide sun visor 301 so as to hit the side visor 302 when the side visor 302 is stored. One side of the side visor 302 is supported by a ball joint 304. 305 is an inside mirror 306, and OX is a vehicle center line.

Further, as shown in FIG. 16, by using the above-mentioned projection 303 as the switch 307, the slide sun visor cannot be stored when the side visor 302 is used, and the switch is turned on by storing the side visor, and the slide sun visor is stored. Can be done.

 Next, the operation of the present embodiment will be described.

Since the side visor 302 is constantly pressed by the projection 303 during storage, the slide sun visor 301 slides out and at the same time, the lower end of the side visor 302 also floats up, making it easy to catch a hand. Further, the support of the side visor 302 can be adjusted on the side regardless of the angle of the slide sun visor 306 because the ball joint 303 is provided on one side.

Here, the flow at the time of slip detection according to the present invention to the slide electric sun visor with the side visor will be described.
This will be described with reference to FIG.

First, this flow starts when the ignition key of the car is turned on. At this time, the CPU 78 detects the sun visor position detection (step 300) in the same manner as the door mirror open / closed state detection signal F shown in FIG. If the sun visor is open at this time, go to step 302. Otherwise go to step 320. In step 302, this step 302 is looped whenever the operator uses the side visor and goes out of the sun visor. Otherwise (if the side visor is stored in the sun visor), go to step 310. The subsequent steps in the flow are exactly the same as those in FIG. However, when the operation switch not described in FIG. 8 is operated, the user is separated from the flow. However, in the present flow (FIG. 17), when the operation SW is operated in step 302, no priority is given. this is,
If the side visor is operated in a state where it is not stored in the sun visor, the side visor, the sun visor, and the like may be damaged.

As described above, when the sun visor is moved by input (manual) without pressing the operation switch, such as at the time of panic due to wandering while driving, in the electric sun visor device using the ultrasonic motor with or without the side visor, In addition, since the motor is driven by detecting the slip between the rotor and the stator of the motor, wear of the sliding surface between the rotor and the stator or generation of abnormal noise can be prevented, and the sun visor can be easily opened and closed, and the operation can be performed. Safety inside can be improved.

In the 37th embodiment described above, an example of application to an automobile equipment device is shown, but the present invention is not limited to an automobile.

[Effects of the Invention] As described above, according to the present invention, when the motor is not driven, the slip vibration is detected when a torque greater than the holding torque is applied between the rotor and the stator in the ultrasonic motor by an external force. Since the configuration is such that the motor can be driven, it is possible to obtain an effect that the durability can be prevented from being deteriorated due to wear of the sliding surface of the motor.

[Brief description of the drawings]

1 is a sectional view of an ultrasonic motor according to a first embodiment of the present invention, FIG. 2 is a block diagram of a drive circuit of the first embodiment, FIG. 3 is a front view of the first embodiment, and FIG. FIG. 5 is an output torque-pressure characteristic diagram, FIG. 6 is an S-phase output waveform diagram due to slip vibration, FIG. 7 is a top view showing a door mirror state of the first embodiment, and (a) is closed. , (B) is open, (c)
FIG. 8 is a view showing an over-open state, FIG. 8 is a flowchart of the first embodiment when the door mirror manual rotation slip detection motor is not operated,
9 is a perspective view showing a schematic configuration of the second embodiment, FIG. 10 is an operation state diagram of the second embodiment, FIG. 11 is an explanatory diagram of the operation of the slider of the second embodiment, and FIG. 13 is a side view showing another configuration of the second embodiment, FIG. 13 is a side view showing still another configuration of the second embodiment, FIG. 14 is a perspective view of FIG. 13, and FIG. 15 is a third embodiment. (A) is a perspective view as viewed obliquely from above and front, (b) is a perspective view as viewed from above in a vehicle compartment,
(C) is a sectional view taken along the line CC of (b), and FIG. 16 is FIG. 15 (c).
FIG. 17 is a schematic view of storing the side visor, and FIG. 17 is a flowchart of the manual slip detection of the sun visor when the motor is not operated. 10 Base, 2 Plate 30 Center shaft 40 Door mirror body (flapper) 43 Spring 49 Rotor (rotor, operation) 50 Bracket 53 53 Elastic body 53A ... Stator (ultrasonic transducer) 55 ... Piezoelectric body (electrostrictive element) 55C ... S-phase detection electrode (detection means) 78 ... CPU, 78a ... control means 101 ... limit switch 120 ... ultrasonic motor 190 Door mirror device 203 Sun visor 206 Ultrasonic motor 301 Slide sun visor 302 Side visor

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masayuki Nita 2 Takaracho, Kanagawa-ku, Yokohama-shi, Kanagawa Nissan Motor Co., Ltd. (56) References JP-A-1-185174 (JP, A) JP-A-61 -41643 (JP, A) JP-A-2-179279 (JP, A) JP-A-3-265475 (JP, A)

Claims (1)

(57) [Claims] An ultrasonic transducer having a plurality of electrostrictive elements fixed to an elastic body, a moving body pressurized and contacted with the elastic body, and vibrations having frequencies different in phase with respect to time are generated in the electrostrictive elements. A first circuit device and a second circuit device to be driven, a detecting means for detecting the vibration of the vibrator, and driving both the first circuit device and the second circuit device when driving the moving body. And control means for driving one or both of the first circuit device and the second circuit device when the vibration of the vibrator is detected by the detection means when the moving body is not driven, and connected to the moving body. Ultrasonic motor device having an equipment device such as a closed door mirror.