JP2003102184A - Actuator, wiper, display, and motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an actuator capable of driving a bar-like member, in a simple structure without using electromagnetic motor or the like. SOLUTION: A drive body 1, using a bimorph piezoelectric element, is mounted onto a rotary shaft 2. The shaft is rotatably supported by a holder 12 of a bearing. A leaf spring 13 is mounted to the top end part of the holder 12. The leaf spring 13 is elastically in contact with a top end part of the rotary shaft 2, and imparts rotation resistance against the rotary shaft 2 by friction force, when the rotary shaft 2 is rotated. A driver impresses a voltage, having a saw-tooth shaped waveform to the driving body 1 through wiring passing in the hollow rotary shaft 2. The drive body is vibrated to the right and left by the saw-tooth shaped voltage, and rotatingly driven in a predetermined direction on the rotary shaft 1, due to the differences in inertia forces caused by a difference of displacement speeds.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator in which a driving body oscillates or rotationally moves around a rotation axis, and particularly to an instrument such as a wiper device or a speedometer attached to an automobile or an outdoor surveillance camera. It relates to technology that is effective when applied.

[0002]

2. Description of the Related Art Conventionally, it has been known in the industrial field to obtain a certain action and effect such as wiping of a glass surface and numerical indication by driving a rod-shaped member such as a wiper blade for an automobile, a speedometer, a hand of a timepiece. Not only can it be found in everyday life, too. In order to drive such a rod-shaped member, an electromagnetic motor or an actuator that is rotationally driven by hydraulic / pneumatic pressure is generally used for the shaft portion.

[0003]

However, since such an electromagnetic motor has a considerable size itself, there is a problem that it is restricted in design and installation. For this reason, for example, on the front surface of a small CCD camera, although it is desirable to attach a wiper device to secure the field of view, there is an adverse effect such that the wiper device must be abandoned due to space limitations. It was In addition, a conventional drive structure using an electromagnetic motor or the like often requires a reduction mechanism and a link mechanism in addition to the motor, which tends to increase the weight of the device and increase the cost. There was also a problem.

An object of the present invention is to provide an actuator or the like that can drive a rod-shaped member with a simple structure without using an electromagnetic motor or the like.

[0005]

SUMMARY OF THE INVENTION An actuator of the present invention is a drive body having a vibrating portion at least in a part thereof, a shaft member to which the drive body is attached, and a bearing for rotatably supporting the shaft member. And a resistance imparting means for imparting a rotational resistance force to the shaft member when the shaft member rotates.

In the actuator of the present invention, the shaft member supported by the bearing portion rotates in response to the vibration of the driving body, and the driving body performs rotational movement or swinging movement. That is,
As a basic configuration, it is possible to rotate the drive body with a simple configuration including four points of the drive body, the shaft member, the bearing portion, and the resistance applying means. Therefore, it is possible to realize a small and lightweight actuator that rotationally drives a driving body formed of a rod-shaped member or the like without using an electromagnetic motor or a link mechanism. As a result, there is no restriction on the installation location of the actuator due to the motor or the link, the layout property of the apparatus is improved, and the actuator that is rotationally driven can be attached to a small and small place.

In the actuator, the resistance applying means may be configured to apply a rotational resistance to the shaft member by a frictional force. In this case, the resistance force applying means may be provided in the bearing portion, and as the resistance force applying means, a leaf spring elastically contacting the shaft member is adopted, and the leaf spring is used as an end portion or a side portion of the shaft member. You may arrange | position so that it may contact elastically. Further, the resistance applying means may be provided on the shaft member, and it is also possible to use an engaging piece elastically contacting the bearing portion as the resistance applying means.

Further, in the actuator, the driving body may be formed of a bimorph type piezoelectric element, for example. In this case, a voltage having a sawtooth waveform may be applied to the piezoelectric element.

Further, in the actuator, a gap extending in the axial direction may be formed inside the shaft member, and wiring for power supply to the driving body may be provided through the gap. In addition, in the actuator, a plurality of the driving bodies may be attached to the shaft member.

On the other hand, the wiper device of the present invention comprises a wiper blade provided on the wiping surface and provided with a driving body having a vibrating portion at least in a part thereof, a shaft member to which the wiper blade is attached, It is characterized by having a bearing portion that rotatably supports the shaft member, and a resistance force applying unit that applies a rotational resistance force to the shaft member when the shaft member rotates.

In the wiper device of the present invention, the wiper blade supported by the bearing portion rotates in response to the vibration of the driving body, and the wiper blade performs rotational movement or swinging movement. Therefore, it is possible to realize a small and lightweight wiper device that rotates and drives the wiper blade without using an electromagnetic motor or a link mechanism. As a result, there are no restrictions on the installation location of the wiper device due to motors and links,
The layout of the device can be improved, and the wiper device can be attached to a small space.

Further, the wiper device may be arranged in front of a CCD camera, and the wiper device may be provided in a CC.
You may make it accommodate in the wiper unit which can be attached to the front surface of a D camera. Further, the wiper device may be applied to a CCD camera mounted on an automobile.

Further, the display device of the present invention rotatably supports the pointer formed by the driving body having a vibrating portion at least in a part thereof, the shaft member to which the pointer is attached, and the shaft member. It is characterized by comprising a bearing portion and a resistance force applying means for applying a rotational resistance force to the shaft member when the shaft member rotates.

In the display device of the present invention, the pointer, which is supported by the bearing portion, rotates in response to the vibration of the driving body, and the pointer makes a rotational movement or a swinging movement. Therefore, it is possible to realize a small and lightweight display device in which the hands are rotated and driven without using the electromagnetic motor. In addition, in the present invention, not only the case where the pointer itself is formed by the driving body, but also the mode in which the driving body is added to the separately formed pointer is possible. Further, not only the case where the pointer is directly attached to the shaft member, but also a mode in which the driver having the pointer is attached is possible.

In this case, the display device may be a speedometer which displays the vehicle speed by the pointer. In addition, it is possible to further install a pointer position detection sensor for detecting the position of the pointer on the display device.

Further, in the motor of the present invention, at least a part thereof has a vibrating portion, a rotating shaft to which the driving body is attached, a bearing portion for rotatably supporting the rotating shaft, and And a resistance applying means for applying a rotational resistance to the rotating shaft when the rotating shaft rotates.

In the motor of the present invention, the rotary shaft rotates in a predetermined direction according to the vibration of the driving body. In this case, for example, a bimorph type piezoelectric element or the like is used as the driving body, and the portion that applies the driving force to the rotating shaft can be configured to be lightweight. For this reason, it is possible to form a motor that is small and lightweight and has a small inertia and excellent responsiveness.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION (Embodiment 1) Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a conceptual diagram showing the basic configuration of an actuator according to the present invention, and FIG. 2 is a perspective view showing the configuration of an oscillating actuator which is Embodiment 1 of the present invention.

As shown in FIG. 1, an actuator according to the present invention includes a flat plate-shaped drive body 1, a rotary shaft (shaft member) 2 to which the drive body 1 is attached, and a bearing portion 3 supporting the rotary shaft 2. It consists of The driving body 1 is formed of a bimorph piezoelectric element which is one of electro-mechanical conversion elements, and a voltage is appropriately applied from a driver 5 via the wiring 4. As a result, the entire driving body 1 bends with the mounting portion to the rotating shaft 2 as a base portion, and the tip end thereof operates in the X direction in FIG. Further, the rotating shaft 2 is rotatably supported by the bearing portion 3 and, at the time of its rotation, a rotational resistance force is applied in a direction in which the rotation is restricted. This rotational resistance force is applied in the form of frictional force, for example, and is applied by the leaf spring 13 in the actuator of FIG.

Here, in the actuator 11 of FIG.
The rotary shaft 2 to which the driving body 1 is attached is attached to the holder 12. The holder 12 plays the role of the bearing portion 3 in FIG. 1, and the rotary shaft 2 is rotatably attached thereto. In the actuator 11,
A piezoelectric element having a length of 20 mm and a height of 3 mm is used as the driving body 1, and the rotary shaft 2 is formed to have a diameter of 4 mm.

A leaf spring (resistance force imparting means) 13 is attached to the upper end of the holder 12 so as to impart a rotational resistance force by frictional force at the top (end) of the rotary shaft 2. As will be described later, in the actuator, the rotational resistance force applied to the rotary shaft 2 is a point that governs its operation, and how to stably apply the rotational resistance force is a major issue. In this case, it is possible to insert a screw into the rotary shaft and adjust the rotation resistance force by the degree of tightening, but the adjustment allowance is small and a stable resistance force cannot be obtained. Therefore, in the actuator 11, the leaf spring 13 is used to apply a rotational resistance force to the rotary shaft 2 by a frictional force, and an appropriate and stable load is applied to the rotary shaft to stabilize the rotational resistance force.

In this case, the leaf spring 13 is fixed to the holder 12 by the set screw 24. A fitting hole 14 is formed at the tip of the leaf spring 13, and the rotary shaft 2 is formed therein.
The small-diameter portion 15 formed on the upper part of the is fitted. Then, the lower surface of the leaf spring 13 elastically contacts the end surface of the step portion of the rotary shaft 2 where the small diameter portion 15 is formed, and imparts a rotational resistance force to the rotary shaft 2. As a result, a stable load can be applied to the rotary shaft 2 with a simple and compact structure, and a stable rotational resistance force can be applied.

In addition, since the rotary shaft 2 and the bearing portion 3 are used here as the portion for imparting the rotational resistance force, the resistance force can be imparted by using originally necessary components, and therefore a large number of dedicated components are added. It is possible to realize the rotation resistance imparting structure. Furthermore, since the resistance imparting structure is provided on the rotary shaft 2, even when the present actuator is applied to, for example, a wiper device, dust is unlikely to be applied and sealing can be easily performed. Therefore, the friction coefficient between the leaf spring 13 and the rotary shaft 2 can be stabilized, and a stable rotation resistance force can be given.

The leaf spring may be in elastic contact with the side portion of the rotary shaft 2 as shown in FIG. In this case, a small diameter portion 16 and a flange portion 17 are formed on the rotary shaft 2. A recess 18 is formed in the holder 12, and the flange portion 17 is placed on the upper surface of the holder 12 to accommodate the small diameter portion 16 in the recess 18. A leaf spring 19 is arranged so as to close the opening of the recess 18, and the leaf spring 19 is elastically contacted with the small diameter portion 16 to impart a rotation resistance force to the rotary shaft 2.

Further, when applying the rotational resistance force to the rotary shaft 2, not only the structure for providing the bearing unit 3 side as described above, but also the structure for providing the rotary shaft 2 side can be adopted. is there. That is, as shown in FIG. 4, a clip-shaped engaging piece 20 may be provided on the rotating shaft 2 and the engaging piece 20 may be fitted into a mounting hole 21 formed in the bearing portion 3 to obtain a frictional force.
In this case, the engaging piece 20 is divided into four pieces at the tip of the rotary shaft 2, and is inserted into the mounting hole 21 while bending so as to be recessed inward. Then, the locking portion 22 at the tip projects to the outside of the mounting hole 21 and engages with the lower surface of the bearing portion 3. At this time, the engagement piece 20 is elastically returned, and the outer surface thereof is attached to the mounting hole 21.
Elastically contacts the inner surface of the. Thereby, the engagement piece 20
A frictional force is generated between the mounting hole 21 and the mounting hole 21, and a rotational resistance force is applied to the rotating shaft 2.

FIG. 5 is an explanatory view showing a power supply structure in the actuator of FIG. In the actuator 11,
The rotating shaft 2 is hollow, and a void 23 is formed inside the rotating shaft 2 along the axial direction. As shown in FIG. 5, a wiring 4 for supplying electric power to the driving body 1 is passed through the void 23. That is, the actuator 1
In No. 1, the wiring is not routed outside the driving body 1, but the wiring is housed inside the device. Therefore, although the wiring 4 itself is twisted to some extent in accordance with the operation of the driving body 1, the wiring 4 is not rotated together with the driving body 1 and damage to the wiring 4 can be prevented. Further, the wiring 4 can be smoothly passed through the inside of the apparatus main body, and the wiring 4 is not exposed outside the apparatus,
It is also possible to improve the waterproofness of the electric system.

On the other hand, the actuator 11 performs a rotary motion about the rotary shaft 2 by applying a sawtooth voltage as shown in FIG. FIG. 6 is an explanatory diagram showing the waveform of the voltage applied to the actuator 11, and FIG. 7 is an explanatory diagram showing the behavior of the driving body 1 when the voltage of FIG. 6 is applied. In this case, the driving body 1 is displaced rightward in FIG. 7 when the voltage is +, and is displaced leftward in the drawing when the voltage is −.

Therefore, when the applied voltage is changed as shown in FIG. 6, first, the voltage is ± 0 in the case of (1) of FIG. 6, and the driving body 1 is in the stopped state at the initial position P ₀ . Next, FIG.
When the voltage is changed to the state of (2), since it is + voltage, the driving body 1 is displaced rightward as shown in FIG. 7 (1 → 2). After that, the voltage changes from + to − as shown in (2 → 3) of FIG.
When the driving force is changed to, the driving body 1 also changes accordingly.
→ Displace to the left as shown in 3).

In this case, since the voltage change of (2 → 3) in FIG. 6 is rapid, there is a difference in the deformation speed of the driving body 1 from the case where the voltage changes slowly as shown in (1 → 2) of FIG. Occurs. That is, the driving body 1 bends slowly at (1 → 2) and sharply bends at (2 → 3). At that time, the driver 1
An inertial force that tends to remain in place is generated due to its weight. Then, from the deformation speed difference of the driving body 1, (1 →
The inertial force in the case of (2 → 3) is larger than the inertial force in the case of 2).

A rotational resistance force applied to the rotary shaft 2 acts on the inertial force. That is, the inertial force and the frictional force oppose each other as the driving body 1 is deformed. In the actuator, the rotational resistance Fr is set to be larger than the inertial force F ₁₂ when (1 → 2) and smaller than the inertial force F ₂₃ when (2 → 3) (F ₁₂ <Fr
<F ₂₃ ). Therefore, the inertial force F _{12 in} the case of (1 → 2) is
The rotation resistance force Fr cancels the driving force, and the driving body 1 is slowly displaced by an angle corresponding to the voltage value. In contrast, in the case of (2 → 3) is an inertial force F ₂₃ is not canceled by the rotation resistance force Fr. Therefore, the driving body 1 is rapidly displaced in the opposite direction according to the voltage change, but the angle corresponding to the voltage value cannot be displaced, and the driving body 1 cannot be completely returned.

That is, in the case of (2 → 3), the driving body 1
The influence of its own inertia becomes large, and the displacement amount of the driving body 1 to the left becomes smaller than the displacement amount to the right of (1 → 2). Therefore, the driving body 1 moves to the right side in the figure by the difference in the displacement amount. In FIG. 7, the line segment Q indicates the center position of the driving body 1 after one reciprocating vibration, and
As shown in → 3) and (4 → 5), it is understood that this line segment Q is also moving to the right along with the vibration of the driving body 1 (Q ₁
→ Q _2). The alternate long and short dash line P ₀ in FIG.
The position (initial position) of the driving body 1 in the case of (1) is shown.

With a sawtooth-shaped applied voltage, as shown in FIG.
After the voltage changes abruptly at (3), the voltage gradually changes to the + side at (3) → (4), and the driver 1 adjusts to the voltage change as shown in FIG. 7 (3 → 4). Displaces to the right like.
In this case, since the voltage change rate is small, the influence of the inertia of the driving body 1 is small, and the driving body 1 is displaced rightward by the displacement amount corresponding to the voltage. When the voltage reaches (4) in FIG. 6, the voltage again suddenly changes to (5). At this time, as described above, the inertial force is generated based on the speed difference of the deformation of the driving body 1, and
→ The displacement amount of the driving body 1 to the left in 5) is shown in Fig. 7 (3
→ It becomes smaller than the displacement to the right in 4). Therefore,
The driver 1 moves to the right side in the figure by the difference in displacement amount, and the line segment Q also moves to the right side.

When the sawtooth voltage is applied in this manner, the inertial force based on the speed difference of the deformation of the driving member causes the driving member 1 to move.
Gradually moves to the right as shown in FIG. 7 and rotates counterclockwise (see the operation of the line segment Q). That is, by repeating the operation of slowly bending and rapidly returning, the driving body 1 self-propels on the displacement side when slowly bending. Then, contrary to FIG. 6, the voltage change is slowly changed to the − side, and suddenly +
By changing to the side, the driving body 1 rotates to the left (clockwise) in FIG. 7. Therefore, by switching the voltage change pattern, the driving body 1 can be appropriately reciprocated, and an oscillating actuator can be configured without using a motor or a link mechanism.

Thus, in the actuator 11,
It becomes possible to rotate the driving body 1 with a simple structure. In this case, an electromagnetic motor or a link mechanism is not required to drive the driving body 1, and a small and lightweight actuator for rotating and driving a rod-shaped member can be realized without using these. As a result, there is no restriction on the installation position of the actuator due to the motor or the link, the layout property of the device is improved, and the actuator that is rotationally driven can be attached to a small and small place.

(Second Embodiment) Next, as a second embodiment of the present invention, an example in which the actuator 11 of FIG. 2 is applied to a wiper device of a CCD camera will be described. Figure 8
It is explanatory drawing which shows the structure, and one part is fractured and shown. In the following embodiments, the same members, parts and the like as those in the first embodiment will be designated by the same reference numerals and the description thereof will be omitted.

Recently, an automobile equipped with a CCD camera has been introduced so that a vehicle or a person approaching the vehicle can be visually recognized at an intersection with poor visibility, a T-shaped road, or the like without making the vehicle deeply enter the intersection. . There, CCD cameras are placed inside the side bumpers and front grille,
The left and right images obtained there are displayed on the in-vehicle display. However, in rainy weather or the like, there are cases in which the function of ensuring the visibility cannot be fully achieved due to water droplets attached to the glass surface in front of the CCD camera. In this case, the field of view can be secured by attaching a wiper device to the front of the CCD camera. However, as described above, since a motor is required to drive the wiper blade, the size of the entire apparatus becomes large, and there is a problem that it cannot be mounted in a narrow space.

On the other hand, the wiper device using the actuator according to the present invention does not require a motor, and the entire device can be made small. As shown in FIG. 8, the wiper device 31 includes the actuator 11 of FIG.
Is attached to the cover 32, and is formed as a wiper unit that can be externally attached to the front surface of the CCD camera 33.

In this case, a rubber blade rubber 34 is attached to the driving body 1, and a wiper blade 35 is attached.
Is formed. The wiper blade 35 is CC
Glass surface (wiping surface) 36 provided on the front surface of the D camera 33
The upper part is swingably provided about the rotary shaft 2.
Then, by appropriately applying a voltage to the driving body 1 from a driver (not shown), the wiper blade 35 oscillates on the glass surface 36, and water drops and dust on the surface are removed.

As described above, the wiper device 31 does not require an electromagnetic motor or a link mechanism for driving the blade, so that the wiper device can be reduced in size and weight. Further, since the blade position is not restricted by the motor or the link, the layout property of the device is improved. Therefore, it becomes possible to install the wiper device in a narrow and small place, and the CC for the vehicle is mounted.
The wiper device can be attached not only to the D camera but also to a portion where the wiper device has not been conventionally installed due to the installation space. In addition, the wiper device 31
Has a unit structure that is integrated with the cover 32, so that it does not require any additional work on the CCD camera 33 main body.
It can be mounted on the front surface of the CCD camera 33.

In the wiper device 31 described above, an example in which the actuator using the configuration of FIG. 2 is applied is shown, but the actuator portion may have the configuration of FIG. Further, in the wiper device 31, the leaf spring 13 can be eliminated when the blade rubber 34 imparts a rotational resistance force.

(Third Embodiment) Further, as a third embodiment of the present invention, an example in which the actuator 11 of FIG. 2 is applied to a speedometer will be described. 9A and 9B are explanatory views showing the structure thereof. FIG. 9A is a front view of the speedometer, and FIG. 9B is a sectional view of a pointer portion.

In this embodiment, as shown in FIG.
The driver 1 is used as the pointer 42 of the speedometer 41. That is, the pointer 42 itself is formed by the piezoelectric element. In this case, the pointer 42 is the meter display plate 4
It is fixed to the rotary shaft 2 which is arranged so as to project from 3.
The rotating shaft 2 is rotatably supported by a ring-shaped bearing portion 3 provided on the back surface side of the meter display plate 43. The rotary shaft 2 is slightly press-fitted into the bearing portion 3, and a rotational resistance force is applied to the rotary shaft 2 there. That is, here, the bearing portion 3
It is itself a resistance imparting means.

At the lower end of the rotary shaft 2, there is provided a sensor plate 44 having a plurality of magnetic poles magnetized along the circumferential direction. A rotation sensor (pointer position detection sensor) 45 is installed near the sensor plate 44. The rotation sensor 45 is a sensor that detects to which position the pointer 42 has moved as a result of energization of the driving body 1, and detects the rotation angle of the pointer 42 by capturing the magnetic pole change accompanying the rotation of the sensor plate 44. .

Then, from the driver 5 to the driving body 1,
By applying a voltage according to the vehicle speed, the pointer 42 rotates around the rotation shaft 2 on the meter display plate 43. At that time, the rotation sensor 45 detects the rotation angle of the pointer 42 and controls the pointer 42 to move to an appropriate position.

As described above, in the speedometer 41, the pointer drive mechanism can be incorporated by utilizing the volume of the pointer portion, and the electromagnetic motor for driving the pointer 42 becomes unnecessary. Therefore, the size and weight of the meter can be reduced, and
The layout of the device is also improved. Further, since the pointer 42 formed by the driving body 1 can be installed by simply inserting it into the rotary shaft 2 protruding from the meter display plate 43, the assembling property can be improved. In this case, it is also possible to adopt a configuration as shown in FIG. 4 for the rotary shaft 2 and insert it into the bearing portion 3 provided on the back of the meter display plate 43.

In the present embodiment, not only the pointer 42 is constituted by the driving body 1, but also the driving body 1 may be attached to the pointer made of synthetic resin or metal. Moreover, the said structure can be used also for general instruments and clocks which have a pointer. In particular, since the pointer 42 is held on the spot due to the rotational resistance force even when the energization is stopped, it is suitable for an instrument with a small change in numerical value, an instrument for displaying a measured value in a stationary needle type, and the like. Furthermore, since it is possible to display numerical values without always energizing, it is possible to save electric power.

(Fourth Embodiment) In addition, as a fourth embodiment of the present invention, a motor using the actuator 11 of FIG. 2 will be described. FIG. 10 is an explanatory diagram showing the configuration. In the actuator 11, not only the swinging motion of the wiper device but also the swinging actuator may be configured to form the motor 51 as shown in FIG. Further, the number of the driving bodies 1 used therein is not limited to one, and it is possible to attach a plurality of driving bodies 1 to the rotary shaft 2 to enhance the output.

In the motor 51, the two driving bodies 1 are attached to the rotary shaft 2, and the housing 52 is provided so as to cover them. The rotating shaft 2 is a base plate 5
3 is rotatably supported by a bearing (bearing portion) 54 attached to No. 3 and a metal bearing 55 attached to the upper surface of the housing 52. In this case, the rotary shaft 2 is attached to the metal bearing 55 slightly like a press fit, and the metal bearing 55 adds a rotational resistance force.

The rotary shaft 2 is hollow, and a wiring 4 for supplying electric power to the driving body 1 is provided in the void 23 inside the rotary shaft 2.
Has been passed through. Further, a slip ring 56 connected to the wiring 4 is attached to the upper part of the rotary shaft 2,
A voltage is applied from the driver 5 via the slip ring 56. The slip ring 56 is housed in a case 57 attached to the upper part of the housing 52.

When the sawtooth voltage as described above is applied to such a motor 51, the driving body 1 as shown in FIG.
By the action of, the rotating shaft 2 can be rotated in a desired direction. In this case, the output torque of the rotary shaft 2 can be controlled by the applied voltage value to the driving body 1. Further, by changing the frequency of the sawtooth voltage, the rotation speed (rotation speed) of the rotary shaft 2 can be changed. Further, the output torque can be appropriately changed depending on the number of the installed driving bodies 1. In this case, for example, a slip ring 56 may be provided for each driving body 1, and the number of driving bodies 1 to which a voltage is applied may be changed to adjust the output.

Further, in the motor 51, the rotating shaft 2 is driven by the driving body 1 composed of a bimorph type piezoelectric element or the like, so that the portion for applying the driving force to the rotating shaft 2 can be made lightweight. For this reason, it is possible to form a motor that is small and lightweight and has a small inertia and excellent responsiveness.

The number of the driving bodies 1 installed in the motor 51 is not limited to two. Further, it is also possible to adopt a configuration in which a leaf spring, rubber or the like is brought into sliding contact with the rotation shaft 2 as the rotation resistance adding means. Furthermore, the slip ring 56
Need only be capable of supplying electric power to a rotating object, and for example, a commutator may be attached instead.

It is needless to say that the present invention is not limited to the above-mentioned embodiment, and can be variously modified without departing from the scope of the invention. For example, in the above-described embodiment, the example in which the rotational resistance force is applied by the frictional force has been described, but this can be performed by a brake using magnetism or an electromagnetic brake. Further, also in the case of frictional force, the applying means is not limited to the leaf spring, and it is also possible to apply the rotational resistance force by a coil spring or rubber which is internally or externally provided in the rotating shaft. Further, as the leaf spring that imparts the rotational resistance force, not only the bearing portion but also the one attached outside the actuator can be used. For example, in the wiper device 31 shown in FIG.
You may attach the leaf spring 13 to 2.

In addition, the driving body 1 does not necessarily have to vibrate in its entirety, and if the movement as shown in FIG. Is. Needless to say, the size of the driving body 1 is merely an example, and the size is not limited to the above size. Further, the voltage applied to the driving body 1 is not limited to the saw-toothed one as described above.

[0055]

According to the actuator of the present invention, a shaft member to which a driving member having a vibrating portion is attached, a bearing portion rotatably supporting the shaft member, and a rotational resistance force to the shaft member are provided. Since the resistance applying means for applying is provided, it is possible to rotate the driving body with a simple configuration. Therefore, it is possible to realize a small and lightweight actuator that rotationally drives a driving body without using an electromagnetic motor or a link mechanism. As a result, there is no restriction on the installation location of the actuator due to the motor or the link, the layout property of the apparatus is improved, and the actuator that is rotationally driven can be attached to a small and small place.

Further, according to the wiper device of the present invention, the shaft member, which is disposed on the wiping surface and has the drive member having the vibrating portion at least in a part thereof, is attached, and the shaft member. A bearing portion that rotatably supports,
Since the resistance applying means for applying the rotational resistance to the shaft member is provided, it is possible to realize a small and lightweight wiper device that rotationally drives the wiper blade without using an electromagnetic motor or a link mechanism. As a result, there are no restrictions on the installation location of the wiper device due to motors and links,
The layout of the device can be improved, and the wiper device can be attached to a small space.

Further, according to the display device of the present invention, a shaft member to which a pointer formed by a driving body having a vibrating portion is attached at least at a part thereof, and a bearing portion rotatably supporting the shaft member. Since the resistance force applying means for applying the rotation resistance force to the shaft member is provided, it is possible to realize a small and lightweight display device for rotationally driving the pointer without using an electromagnetic motor.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a basic configuration of an actuator according to the present invention.

FIG. 2 is a perspective view showing a configuration of a swing-type actuator that is Embodiment 1 of the present invention.

FIG. 3 is an explanatory diagram showing another example of a rotational resistance imparting structure in the actuator of FIG.

FIG. 4 is an explanatory diagram showing still another example of the rotational resistance imparting structure in the actuator of FIG.

5 is an explanatory diagram showing a power supply structure in the actuator of FIG. 2. FIG.

FIG. 6 is an explanatory diagram showing a waveform of a voltage applied to the actuator of FIG.

FIG. 7 is an explanatory diagram showing the behavior of the driving body when the voltage of FIG. 6 is applied.

8 is an explanatory diagram showing a configuration of a wiper device that is Embodiment 2 of the present invention to which the actuator of FIG. 2 is applied,
This is a partially broken view.

9A and 9B are explanatory views showing the configuration of a speedometer that is Embodiment 3 of the present invention to which the actuator of FIG. 2 is applied, where FIG. 9A is a front view of the speedometer, and FIG. 9B is a sectional view of a pointer portion. Is.

10 is an explanatory diagram showing the configuration of a motor that is Embodiment 4 of the present invention to which the actuator of FIG. 2 is applied.

[Explanation of symbols]

1 driver 2 rotating shafts (shaft members) 3 Bearing 4 wiring 5 drivers 11 Actuator 12 holder 13 Leaf spring (resistance force applying means) 14 Fitting hole 15 Small diameter part 16 Small diameter part 17 Flange 18 recess 19 leaf spring 20 engagement piece 21 mounting holes 22 Locking part 23 void 24 Set screw 31 Wiper device 32 covers 33 CCD camera 34 blade rubber 35 Wiper blade 36 Glass surface (wiping surface) 41 speedometer 42 pointer 43 meter display board 44 sensor plate 45 rotation sensor 51 motor 52 housing 53 Base plate 54 Bearing 55 Metal bearings (resistance imparting means) 56 slip ring 57 cases

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shu Kasai             Gunma Prefecture Kiryu-shi Hirosawa-cho 1-26-181 Stock             Company Mitsuba (72) Inventor Yuko Kawakura             Gunma Prefecture Kiryu-shi Hirosawa-cho 1-26-181 Stock             Company Mitsuba (72) Inventor Shigeki Aoki             Gunma Prefecture Kiryu-shi Hirosawa-cho 1-26-181 Stock             Company Mitsuba F-term (reference) 5H680 AA19 BB16 BC01 DD01 DD15                       DD23 DD24 DD37 DD65 DD67                       FF32

Claims (20)

[Claims] 1. A drive body having a vibrating part in at least a part thereof, a shaft member to which the drive body is attached, a bearing portion rotatably supporting the shaft member, and a rotating member for rotating the shaft member. An actuator, comprising: a resistance applying unit that applies a rotational resistance to the shaft member. 2. The actuator according to claim 1, wherein the resistance applying means applies a rotational resistance to the shaft member by a frictional force. 3. The actuator according to claim 2, wherein the resistance applying means is provided in the bearing portion. 4. The actuator according to claim 3, wherein the resistance applying means is a leaf spring elastically contacting the shaft member. 5. The actuator according to claim 4, wherein the leaf spring elastically contacts the end of the shaft member. 6. The actuator according to claim 4, wherein the leaf spring elastically contacts a side portion of the shaft member. 7. The actuator according to claim 2, wherein the resistance applying means is provided on the shaft member. 8. The actuator according to claim 7, wherein the resistance applying means is an engagement piece that elastically contacts the bearing portion. 9. The actuator according to claim 1, wherein the driving body is formed by a piezoelectric element. 10. The actuator according to claim 9, wherein a voltage having a sawtooth waveform is applied to the piezoelectric element. 11. The actuator according to claim 1, wherein the shaft member has a void therein that extends in the axial direction, and a wire for feeding power to the driving body through the void. An actuator characterized by performing. 12. The actuator according to claim 1, wherein a plurality of the driving bodies are attached to the shaft member. 13. A wiper blade provided on a wiping surface, the wiper blade having a driving body having a vibrating portion at least in a part thereof, a shaft member to which the wiper blade is attached, and a rotatably supporting the shaft member. A wiper device, comprising: a bearing portion that performs rotation and a resistance applying unit that applies a rotational resistance to the shaft member when the shaft member rotates. 14. The wiper device according to claim 13, wherein the wiper device is provided in front of a CCD camera. 15. The wiper device according to claim 13, wherein the wiper device is housed in a wiper unit attachable to a front surface of a CCD camera. 16. The wiper device according to claim 14, wherein the CCD camera is mounted on an automobile. 17. A pointer formed by a driving body having a vibrating portion at least in a part thereof, a shaft member to which the pointer is attached, a bearing portion rotatably supporting the shaft member, and the shaft member. And a resistance imparting means for imparting a rotational resistance force to the shaft member during rotation of the display device. 18. The display device according to claim 17, wherein
The display device is a speedometer that displays a vehicle speed by the pointer. 19. The wiper device according to claim 17, wherein the display device includes a pointer position detection sensor that detects the position of the pointer. 20. A drive body having a vibrating portion at least in a part thereof, a rotary shaft to which the drive body is attached, a bearing portion rotatably supporting the rotary shaft, and a rotary shaft when the rotary shaft rotates. A resistance applying unit that applies a rotation resistance to the rotating shaft.