JPH0525991U - Ultrasonic motor support structure - Google Patents

Abstract

(57) [Summary] (Modified) [Configuration] An ultrasonic motor support structure having a cylindrical ultrasonic motor 40, a pipe, and a holder, and the ultrasonic motor 40 being housed inside the pipe. At the end of the stator,
A support 16 having at least a cylindrical base 19 and a small diameter portion smaller than the base 19 is formed, the end surface of the base 19 is attached to the inner surface of the holder, and the rotor 34 is fixed to the inner surface of the pipe. [Effect] The ultrasonic motor can be stably supported in a state where the influence on the vibration mode characteristics of the ultrasonic motor is reduced. Since most of the ultrasonic motor can be stored in the pipe, the size of the supporting structure itself of the ultrasonic motor can be reduced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 It is an ultrasonic motor support structure when using an ultrasonic motor that generates a rotational driving force, and does not affect the characteristics of the vibration mode of the ultrasonic motor and does not cause a reduction in the rotational driving force. The present invention relates to an ultrasonic motor support structure that stably stores an ultrasonic motor.

[0002]

[Prior Art]

 The ultrasonic motor has a very high electro-mechanical conversion efficiency, can generate a large driving torque at a constant voltage and at a low speed. Above all, composite oscillator ultrasonic motors that generate stable rotating torque even at low speeds and are easy to control are expected to be used in various fields. FIG. 9 shows an example of a conventional ultrasonic motor support structure that houses this composite oscillator ultrasonic motor. The cylindrical composite vibrator ultrasonic motor 62 includes a stator in which a stator bottom 48, a torsional vibration element 50, a hold block 52, a longitudinal displacement type piezoelectric element 54, and a stator head 56 are sequentially connected by a central axis 60, and a stator. It is generally configured by a rotor 64 that slides with the head 56. The rotor 64 is also connected to the stator by the central shaft 60. The torsional vibration element 50 is a multilayer piezoelectric body made of a piezoelectric material such as lead zirconate titanate or the like, and generates a rotational driving force. The longitudinal displacement type piezoelectric element 54 acts as a clutch during operation. The rotor 64 is pressed against the stator by a spring 66 with a constant pressure.

In the composite vibrator ultrasonic motor 62 having this configuration, the applied voltage having the resonance frequency of the torsional vibration element 50 is applied to the torsional vibration element 50 and the vertical displacement type piezoelectric element 54, respectively. Then, torsional vibration is generated in the torsional vibration element 50, and the longitudinal displacement type piezoelectric element 54 expands and contracts. The rotor 64 can be continuously rotated in one direction by a combination of these vibrations.

Further, the ultrasonic motor support structure shown in FIG. 9 is roughly configured by a holder 44 and a pipe 42 in addition to the ultrasonic motor 62. Spokes 58, 58 are provided between the rotor 64 of the ultrasonic motor 62 and the pipe 42, and the rotational force of the rotor 64 is transmitted to the pipe 42 via the spokes 58, 58.

Further, a flange 46 is provided on the node portion of the ultrasonic motor 62 in the torsional vibration mode. The flange 46 is fixed to the holder 44 and supports the ultrasonic motor 62. It is indispensable that the flange 46 that supports the ultrasonic motor 62 is provided at the node of the torsional vibration mode, and if it is provided at this node, the characteristics of the torsional vibration mode of the torsional vibration element 50 are adversely affected. Instead, the ultrasonic motor 62 can be supported. Further, the node portion in the torsional vibration mode generally occurs at the edge of the hold block 52 on the side of the torsional vibration element 50.

In the ultrasonic motor support structure having the above structure, when the rotor 64 of the ultrasonic motor 62 rotates, its rotational driving force is transmitted to the pipe 42 via the spokes 58, and the pipe 42 rotates. Therefore, the rotational driving force of the ultrasonic motor 62 can be effectively used by attaching the object to which power is supplied to the pipe 42. For example, when this ultrasonic motor supporting structure is provided at the upper end of the window frame and is used as a blind winder, if one end of the blind is attached to the pipe 42, the rotation of the pipe 42 and It can be wound up.

[0007]

[Problems to be solved by the device]

 In the ultrasonic motor support structure having the above-described structure, since the ultrasonic motor 62 is supported by the flange 46, the holder 44 becomes large in size in the radial direction by the amount of the flange 46 provided. Further, since the flange 46 needs to be provided at the node in the vibration mode of the ultrasonic motor 62, in order to store the torsional vibration element 50 and the stator bottom 48, the holder 44 is increased in size in the longitudinal direction. It was something that ended up. Such an increase in the size of the holder 44 is not only unattractive when the ultrasonic motor is attached, but also requires a special installation place for the ultrasonic motor, and the attachment itself is difficult, which is very inconvenient. In particular, when used as a blind winder, a gap was created at the side edge of the blind compared to the window frame.

The present invention has been made to solve the above-mentioned problems, and by forming a support on the stator, the ultrasonic motor can be stably operated without adversely affecting the characteristics of the vibration mode of the ultrasonic motor. It is something to support.

[0009]

[Means for Solving the Problems]

 The ultrasonic motor supporting structure of the present invention has an ultrasonic motor in which a cylindrical stator and a rotor are connected in series on a central axis, a pipe, and a holder. The ultrasonic motor is stored inside the pipe and the end of the pipe is An ultrasonic motor support structure in which a portion is rotatably mounted on a holder, and a support having at least a cylindrical base and a small-diameter portion smaller than the base is formed at the end of the stator. The end face is attached to the inner surface of the holder, and the rotor is fixed to the inner surface of the pipe.

[0010]

[Action]

 In the ultrasonic motor supporting structure of the present invention, the supporting body is formed at the end portion of the stator, and the supporting body is fixed to the holder, so that the ultrasonic motor can be stably supported. At this time, the small diameter portion is formed on the support, so that the influence on the characteristics of the vibration mode of the ultrasonic motor can be reduced. Therefore, the ultrasonic motor can be stably stored in the pipe without adversely affecting the characteristics of the vibration mode.

[0011]

【Example】

 An embodiment of the present invention will be described with reference to FIG. A cylindrical composite vibrator ultrasonic motor 40 has a stator bottom 22, an aluminum ring 23, a torsional vibration element 24, a hold block 26, a longitudinal displacement type piezoelectric element 28, and a stator head 30 which are connected in sequence with a central axis 20. It is roughly composed of a stator and a rotor 34 that slides on the stator head 30. The rotor 34 is also rotatably connected to the stator by the center shaft 20. The torsional vibration element 24 is a laminated piezoelectric body made of a piezoelectric material such as lead zirconate titanate (PZT), and generates a rotational driving force. The longitudinal displacement type piezoelectric element 28 acts as a clutch during operation. The rotor 34 is pressed against the stator by a spring 36 with a constant pressure.

In the composite vibrator ultrasonic motor 40 having this structure, the applied voltage of the resonance frequency of the torsional vibration element 24 is applied to the torsional vibration element 24 and the vertical displacement type piezoelectric element 28, respectively. Then, torsional vibration occurs in the torsional vibration element 24, and the longitudinal displacement type piezoelectric element 28 expands and contracts. By combining these vibrations, the rotor 34 can be continuously rotated in one direction.

Further, as shown in FIG. 1, the ultrasonic motor support structure of the present embodiment is roughly composed of a holder 12 and a pipe 10 in addition to the ultrasonic motor 40. The pipe 10 has a cylindrical shape, the ultrasonic motor 40 is housed therein, and the pipe 10 itself receives the rotational force of the ultrasonic motor 40 to rotate. The holder 12 is provided at the end of the pipe 10, and the holder 12 is fixed to a building material or the like at the place where the ultrasonic motor is installed. Further, the pipe 10 and the holder 12 slide on the sliding portions 14, 14, which are made of oiles metal or the like. Spokes 32, 32 are provided between the rotor 34 of the ultrasonic motor 40 and the pipe 10, and the rotational force of the rotor 34 is transmitted to the pipe 10 via the spokes 32, 32. Incidentally, the spokes 32, 32 may be circular ones as well as radial ones centering on the rotor 34.

Further, in the ultrasonic motor support structure of this embodiment, the support body 16 is provided on the stator bottom 22. Further, the support 16 is adhered to the central portion of the inner side surface 38 of the holder 12. The support 16 has a cylindrical small-diameter portion 18 and a column-shaped pedestal 19 which is thicker than the small-diameter portion 18. The support 16 may be made of stainless steel or the like. The support 16 may be formed separately from the ultrasonic motor and attached to the end of the stator bottom 22, or may be integrated with the stator bottom 22. In the configuration of the present embodiment in which the support 16 having the small diameter portion 18 is interposed between the stator bottom 22 and the inner side surface 38, since the node portion of the vibration mode is generated on the mounting surface of the support 16 to the holder 12, Even if the support 16 is fixed to the holder 12, the adverse effect on the characteristics of the vibration mode is extremely small. Therefore, the characteristics of the vibration mode are not adversely affected, so that the ultrasonic motor 40 can be stably supported without lowering the rotational driving force.

In the ultrasonic motor support structure of the present embodiment, when the rotor 34 of the ultrasonic motor 40 rotates, the rotational driving force is transmitted to the pipe 10 via the spokes 32 and the pipe 10 rotates. Therefore, the rotational driving force of the ultrasonic motor 40 can be effectively used by attaching the object to which power is supplied to the pipe 10. For example, when this ultrasonic motor supporting structure is installed on the upper end of the window frame and is used as a blind winder, if one end of the blind is attached to the pipe 10, the pipe 10 rotates and the blind winds up. Can be done.

In the ultrasonic motor supporting structure of the present embodiment, unlike the ultrasonic motor supporting structure of the conventional example, since the flange of the vibration mode generated in the vicinity of the hold block is not provided, the holder 12 is unnecessary and large. There is no change. That is, most of the ultrasonic motor 40 can be stored inside the pipe 10, and the holder 12 can be downsized. Therefore, the ultrasonic motor support structure of the present embodiment is easy to install, does not cause a gap or the like due to installation of the ultrasonic motor, and improves the appearance.

It should be noted that the present invention is a support structure for an ultrasonic motor, and the ultrasonic motor is not limited to the composite oscillator ultrasonic motor as in the present embodiment, but may be, for example, a traveling waveform ultrasonic motor. Of course, it can be applied to the above.

Test Example The characteristics of the vibration mode of the support 16 under various conditions described below were examined. 2 to 8 shown in the test example, each (a) diagram is a side view of the ultrasonic motor used in each test, (b) a characteristic diagram of the torsional vibration mode, and (c). ) The figure is the characteristic diagram of the longitudinal vibration mode. In the characteristic diagram of each vibration mode, the center straight line is the center axis of the vibration mode, the F line is the characteristic of the vibration mode in which the end face of the support is not fixed, and the C line is the end face of the support. This is the characteristic of the vibration mode in the applied state. Furthermore, in the ultrasonic motor used in each test, the stator bottom 22 and the support 16 are integrated.

<Test 1> First, the characteristics of the vibration mode of the ultrasonic motor in the state where the support was not formed were measured. The results are shown in Figure 2.

As is apparent from FIG. 2, in the ultrasonic motor having no support, the node portion of the torsional vibration mode is generated at the edge of the hold block 26 on the torsional vibration element 24 side (FIG. 2B). It can be seen that the node in the longitudinal vibration mode occurs in the longitudinal displacement type piezoelectric element 28 (FIG. 2C), and the stator bottom 22 vibrates greatly. Therefore, it is apparent that if the end surface 21 of the stator bottom 22 is directly fixed to the holder 12, the characteristics of the vibration mode of the ultrasonic motor are adversely affected.

<Test 2> The characteristics of each vibration mode of the ultrasonic motor in which the pedestal 19 thicker than the small-diameter portion 18 is not formed on the support 16 and the ultrasonic motor formed were examined. That is, in FIG. 3, it is an ultrasonic motor in which a pedestal 19 having the same thickness as that of the small diameter portion 18 is formed, and in FIG. 4, an ultrasonic motor in which a pedestal 19 thicker than the small diameter portion 18 is formed. It is a motor.

Comparing FIG. 3 and FIG. 4, the difference between the torsional vibration modes in the state where the end face 17 of the support 16 is not fixed (F line) and the state where it is fixed (C line) is greater than that in FIG. It can be seen that the ultrasonic motor in FIG. 4 is smaller than the ultrasonic motor. The difference between the longitudinal vibration modes of the state where the end face 17 of the support 16 is not fixed (F line) and the state where it is fixed (C line) is the ultrasonic motor of FIG. 4 rather than the ultrasonic motor of FIG. It turns out that is smaller. That is, it can be seen that the ultrasonic motor of FIG. 4 has a smaller effect on the vibration mode due to the end surface 17 of the support 16 being fixed than the ultrasonic motor of FIG. In other words, it can be understood that by providing the pedestal 19 thicker than the small-diameter portion 18 (in other words, by forming the small-diameter portion 18 with respect to the pedestal 19), the influence on the characteristics of the vibration mode of the ultrasonic motor can be reduced. ..

<Test 3> The dependence of the vibration mode on the length of the small diameter portion 18 of the support 16 was examined. That is, in FIG. 5, it is an ultrasonic motor in which the small diameter portion 18 is long, and in FIG. 6, it is an ultrasonic motor in which the small diameter portion 18 is short.

As is apparent from FIGS. 5 (c) and 6 (c), the ultrasonic motor having the small diameter portion 18 shown in FIG. 5 has a longer length than the ultrasonic motor having the small diameter portion 18 having a shorter length. It can be seen that the characteristics of the vibration mode are more similar when the end surface 17 of the support 16 is not fixed (F line) and is fixed (C line). That is, it can be seen that the ultrasonic motor of FIG. 5 has a smaller influence on the vibration mode due to the fixed end surface 17 of the support 16 than the ultrasonic motor of FIG. That is, when the small diameter portion 18 is longer than it is short, the influence on the characteristics of the vibration mode when the end face 17 of the support 16 is fixed can be reduced.

<Test 4> The dependence of the vibration mode on the thickness of the small diameter portion 18 of the support 16 was examined. That is, in FIG. 7, the ultrasonic motor has a small diameter portion 18 with a small thickness, and in FIG. 8, the small diameter portion 18 has a large thickness.

As is apparent from both the torsional vibration mode and the longitudinal vibration mode of FIGS. 7 and 8, the ultrasonic motor of FIG. 7 has the end face 17 of the support body 16 fixed more than the ultrasonic motor of FIG. It can be seen that the characteristics of the vibration mode in the unfixed state (F line) and the fixed state (C line) are similar. That is, it can be seen that the ultrasonic motor of FIG. 7 is less affected by fixing the end surface 17 of the support 16 than the ultrasonic motor of FIG. That is, if the small diameter portion 18 is thinner than thick, the influence on the vibration mode characteristics of the ultrasonic motor can be reduced.

From the above test results, the following four points become clear. By forming the support having the small diameter portion and the pedestal at the end of the stator bottom, it is possible to reduce the influence on the vibration mode characteristics of the ultrasonic motor even if the end surface of the support is fixed to the holder. The larger the pedestal, the smaller the influence on the characteristics of the vibration mode of the ultrasonic motor when the end surface of the support is fixed. The longer the small diameter portion, the smaller the influence on the characteristics of the vibration mode of the ultrasonic motor can be reduced when the end face of the support is fixed. The smaller the small diameter portion, the smaller the influence on the characteristics of the vibration mode of the ultrasonic motor when the end surface of the support is fixed. That is, the influence on the vibration mode characteristics of the ultrasonic motor can be further reduced by forming a long support with a large pedestal and a small small diameter portion at the end of the stator bottom.

[0028]

[Effect of the device]

 The ultrasonic motor supporting structure of the present invention has an ultrasonic motor in which a cylindrical stator and a rotor are connected in series on a central axis, a pipe, and a holder. The ultrasonic motor is stored inside the pipe and the end of the pipe is An ultrasonic motor support structure in which a portion is rotatably attached to a holder, and a substantially cylindrical support body having at least a column and a small diameter portion thinner than the column is formed at an end of the stator. The end surface of the pedestal is attached to the holder, and the rotor is fixed to the inner surface of the pipe.

In the structure in which the ultrasonic motor is supported by interposing the support having the small diameter portion between the stator and the holder, the ultrasonic wave is generated in a state where the influence on the characteristics of the vibration mode of the ultrasonic motor is minimized. The motor can be supported stably. Further, since it is not necessary to provide a supporting member such as a flange on the ultrasonic motor and most of the ultrasonic motor can be stored in the pipe, the size of the supporting structure of the ultrasonic motor itself can be reduced. be able to. Therefore, not only can the installation location be reduced at the time of attachment, but also the attachment itself can be facilitated. Also, the appearance is significantly improved.

[Brief description of drawings]

FIG. 1 is a side view of an ultrasonic motor support structure of this embodiment.

2 is a characteristic result of a vibration mode of Test 1, and FIG.
2 is a side view of the ultrasonic motor used in Test 1, and FIG.
(B) is a characteristic result of the torsional vibration mode of Test 1,
FIG. 2C shows the characteristic result of the longitudinal vibration mode of Test 1.

FIG. 3 is a characteristic result of a vibration mode of Test 2, and FIG.
3 is a side view of the ultrasonic motor used in Test 2, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 2,
FIG. 3C shows the characteristic result of the longitudinal vibration mode of Test 2.

4 is a characteristic result of a vibration mode of Test 2, and FIG.
4 is a side view of the ultrasonic motor used in Test 2, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 2,
FIG. 4C shows the characteristic result of the longitudinal vibration mode of Test 2.

5 is a characteristic result of a vibration mode of Test 3, and FIG.
5 is a side view of the ultrasonic motor used in Test 3, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 3,
FIG. 5C shows the characteristic result of the longitudinal vibration mode of Test 3.

6 is a characteristic result of a vibration mode of Test 3, and FIG.
6 is a side view of the ultrasonic motor used in Test 3, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 3,
FIG. 6C shows the characteristic result of the longitudinal vibration mode of Test 3.

7 is a characteristic result of the vibration mode of Test 4, and FIG.
7 is a side view of the ultrasonic motor used in Test 4, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 4,
FIG. 7C shows the characteristic result of the longitudinal vibration mode of Test 4.

8 is a characteristic result of the vibration mode of Test 4, and FIG.
8 is a side view of the ultrasonic motor used in Test 4, and FIG.
(B) is the characteristic result of the torsional vibration mode of Test 4,
FIG. 8C shows the characteristic result of the longitudinal vibration mode of Test 4.

FIG. 9 is a side view of a conventional ultrasonic motor support structure.

[Explanation of symbols]

 Reference Signs List 10 pipe 12 holder 16 support 17 end face 18 small diameter part 19 pedestal 20 center axis 22 stator bottom 24 torsional vibration element 28 longitudinal displacement type piezoelectric element 34 rotor 38 inner side surface 40 ultrasonic motor 42 pipe 44 holder 46 flange 48 stator bottom 50 twisting Vibration element 54 Vertical displacement type piezoelectric element 58 Spoke 60 Central axis 62 Ultrasonic motor 64 Rotor

Claims (1)

[Scope of utility model registration request] 1. An ultrasonic motor comprising a cylindrical stator and rotor connected to each other about a central axis, a pipe, and a holder. The ultrasonic motor is housed inside the pipe and the end of the pipe is rotated by the holder. An ultrasonic motor support structure freely mounted, wherein a support having at least a column-shaped column and a small diameter portion smaller than the column is formed at an end portion of the stator, and an end surface of the column is formed on the end surface of the holder. An ultrasonic motor support structure, characterized in that the rotor is attached to the inner surface and the rotor is fixed to the inner surface of the pipe.