JPH1184451A - Driving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve rigidity around the joining parts of electromechanical conversion elements to driving members, without increasing the number of parts and to suppress the radiation and vibration of the electromechanical conversion elements by adopting such a constitution that entire length ranges including the circumferences of the joining parts of the electromechanical conversion elements to the driving members are covered with covering walls. SOLUTION: In a driving mechanism A, the covering wall 61 for covering a piezo element 22 of a supporting member 15 on a moving frame 3 is formed to extend from the part being on the side of the piezo element 22 and facing it, to a part 21 for fixing the piezo element 22 to the moving frame 3. Further, in a driving mechanism B, the covering wall 62 for covering a piezo element 42 of a supporting member 35 on a fixing frame 4 is formed to extend from the part being on the side of the piezo element 42 and facing it, to a part 41 for fixing the piezo element 42 to the fixing frame 4. By such a constitution, the piezo elements 22 and 42 are protected in such a manner that the entire length ranges including the circumferences of the joining parts to driving shafts 14 and 34 as the driving members are covered with the covering walls 61 and 62.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving apparatus for driving an electromechanical transducer using mechanical movement.

[0002]

2. Description of the Related Art A driving apparatus of this type uses a piezo element known as an impact actuator, for example, and obtains a driving force by vibrating a driving member bonded to one end of the piezo element. FIG. 3 shows a conventional example in which such a drive device is applied to a mechanism that automatically corrects camera shake of a lens system that performs photographing and projection. The lens frame a holding the lens group 1 moves with respect to the moving frame b concentric with the lens frame a in the Y direction perpendicular to the X direction by the fitting portions c and d on both sides on the diameter line in the X direction. The moving frame b is held so as to be able to move in the X direction with respect to the fixed frame e concentric with the moving frame b by fitting portions f and g on both sides on the diameter line in the Y direction. .

[0003] As a result, the ball frame a can move in the XY2 directions perpendicular to each other via the moving frame b with respect to the fixed frame e.
By controlling the movement in these two directions, the camera shake of the lens 1 system is corrected. The driving mechanism for this Y-direction correction includes a piezo element h on the moving frame b side, a driving member i adhesively fixed to the piezo element h, and a ball frame a , The vibration of the driving member i when the piezo element h is driven is transmitted to the moving element j, and the ball frame a The position of the lens 1 system is corrected in the Y direction via. Further, the drive mechanism for correcting in the X direction includes a piezo element k on the side of the fixed frame e and a driving member m adhesively bonded to one of the fitting portions f of the movable frame b and the fixed frame e; And a movable element n fitted so as to be frictionally driven by the driving member m,
The vibration of the driving member m when the piezo element k is driven is transmitted to the moving element n, and the position of the lens system l is corrected in the X direction via the moving frame b.

[0004]

By the way, the piezo elements h and k are vibrated at a high frequency, and the heat generated by the vibrations and the vibration itself may adversely affect the performance of the above-mentioned conventional drive device. is there. Further, the driving members i and m and the piezo elements h and k are small members arranged in a small space of the lens 1 system. And sometimes it is damaged early by the influence of vibration.
Excessive vibration of the piezo elements h and k may cause optical blurring of the lens 1 system. The heat generated by the piezo elements h and k affects the movement of the piezo elements h and k and causes the desired characteristics to not be obtained.

SUMMARY OF THE INVENTION An object of the present invention is to provide a drive device capable of improving rigidity around a joint between an electromechanical transducer and a driving member without increasing the number of parts, and suppressing heat radiation and vibration of the electromechanical transducer. Is to do.

[0006]

According to the present invention, there is provided an electromechanical transducer, a base having one end of the electromechanical transducer fixed by using a fixing portion connected to the one end, and the like. A drive member coupled to the other end and displaced together with the electromechanical transducer, a support member fixed to the base and supporting the drive member so as to guide the drive member in the displacement direction, and a moving member driven by the drive member The basic configuration of the drive device having, when the electromechanical conversion element is driven, the other end side starting from the portion fixed to the base,
With the driving member fixed to the other end, the movable member is displaced from the fixed portion as a starting point, and the moving member driven by the driving member is driven to move by the displacement.

In particular, in order to achieve the above object, the present invention provides a method for extending an electromechanical transducer from a portion of a support member on the base facing the electromechanical transducer to a fixing portion of the electromechanical transducer to the base. One feature is that a covering wall that covers the mechanical conversion element is formed.

As described above, since the electromechanical transducer is covered by the covering wall extending from the support member of the base to the fixing portion of the electromechanical transducer to the base, the electromechanical transducer is connected to the drive member. Since the entire length range including the periphery of the portion is covered and protected by the covering wall, the rigidity of the coupling portion between the electromechanical transducer and the driving member thereof is improved, and the component may be damaged early due to external force or vibration. Will be resolved. Further, since the covering wall is integral with the supporting member and the number of parts does not increase, it does not cause an increase in cost.

According to the present invention, a fixing portion fixed to one end of the electromechanical transducer is fixed to the base, and a support member on the base extends from a portion facing the electromechanical transducer to the fixing portion. Also, a tunnel-like covering wall for covering the electromechanical transducer between the base and the electromechanical transducer is formed.

As described above, since the covering wall that covers the electromechanical transducer is a tunnel-shaped covering wall that extends from the support member of the base to the fixing portion of the electromechanical transducer to the base, the electromechanical transducer and the electromechanical transducer can be connected to each other. Since the entire area around the entire length of the electromechanical transducer including the coupling portion with the driving member is covered, the functions of the protection, heat dissipation, and vibration suppression by the covering wall are further increased, and the durability is further improved.

According to the present invention, a fixing portion fixed to one end of the electromechanical transducer is fixed to the base, and a support member on the base extends from a portion facing the electromechanical transducer to the fixing portion. Further, the present invention is also characterized in that a groove-like covering wall for covering the electromechanical transducer from both sides on the base is formed.

As described above, the covering wall covering the electromechanical transducer is a concave groove-shaped covering wall extending from the support member of the base to the fixing portion of the electromechanical transducer on the base.
A simple form in which the covering wall is open in a concave groove shape while covering the entire length of the electromechanical transducer including the coupling portion between the electromechanical transducer and the driving member from both sides and securing the protection function by the covering wall. Therefore, the manufacturing is easy and the cost can be reduced accordingly. Exposing both the electromechanical transducer and the driving member is convenient for inspection and maintenance.

The present invention is also characterized in that a space around the electromechanical transducer formed by the base and the covering wall is filled with an elastic material having high thermal conductivity.

Since the space around the electromechanical transducer between the base and the covering wall is filled with the elastic material as described above, the vibration of the electromechanical transducer can be absorbed and attenuated. Reduce the effect of vibration of the conversion element,
Durability and driving accuracy can be improved. In addition, since the elastic member is made of a material having good heat conductivity, heat conduction from the electromechanical transducer to the covering wall is promoted, and heat radiation characteristics are improved. In this case, it is desirable that the covering wall is a metal member integrated with the support member.

The present invention is also characterized in that the support member is provided at a plurality of positions in the displacement direction of the drive member, and the cover wall is formed on the side facing the electromechanical transducer. I have.

As described above, when the supporting member is provided at a plurality of positions in the displacement direction of the driving member, the driving member is supported at an optimal position in consideration of the positional relationship with the moving member driven by the driving member. By providing the covering wall on the side of the support member facing the electromechanical transducer, the above-described configuration, operation, and effect can be satisfied regardless of the plurality of support members.

The present invention is described in the following detailed description,
It also has other features shown in the drawings, and these features, including the features described above, can be independently employed as necessary, or can be employed in combination.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Some embodiments of the driving device according to the present invention will be described below in detail with reference to FIGS.

(Embodiment 1) Embodiment 1 is an example of a driving device used in a mechanism for automatically correcting camera shake of a lens system for photographing and projection, as in the conventional example.
The correction of camera shake is performed by moving the annular ball frame 2 in the XY2 directions orthogonal to each other around the optical axis L while holding the lens group 1. For this purpose, the ball frame 2 is supported by a metal-made annular moving frame 3 concentric with the ball frame 2 so as to be movable in, for example, the Y direction among the two directions.
Supports the concentric annular fixed frame 4 so as to be movable in the remaining X direction. As a result, the position of the ball frame 2 is independently adjusted in the Y direction with respect to the optical axis L by the movement in the Y direction with respect to the moving frame 3 in a sandwich state sandwiched between the moving frame 3 and the fixed frame 4. The position of the moving frame 3 is adjusted in the X direction together with the moving frame 3 with respect to the optical axis L by accompanying the movement of the moving frame 3 in the X direction with respect to the fixed frame 4.

The supporting structure of the ball frame 2 for the moving frame 3 and the supporting structure of the moving frame 3 for the fixed frame 4 for these purposes may have any specific configuration.

In the case of the present embodiment, the support mechanism for the ball frame 2 with respect to the moving frame 3 utilizes the fitting portions 6 and 7 provided on both sides of the ball frame 2 and the moving frame 3 on the diameter line in the X direction. I have.

The fitting portion 7 is attached to a pair of bifurcated bearing pieces 11, 11 integrally arranged on the side of the ball frame 2 so as to be parallel to the plane of the ball frame 2 and arranged in the Y direction. The guide shaft 12 which is parallel to the plane of the moving frame 3 fixedly provided on the side of the movable frame 3 and is oriented in the Y direction is fitted so as to slide in the Y direction. The fitting portion 6 includes a bearing portion 13 having a bearing hole 13a parallel to the plane of the ball frame 2 and directed in the Y direction, which is provided integrally with a side portion of the ball frame 2; And a drive shaft 14 which is parallel to the flat surface and is oriented in the Y direction so as to be slidable in the Y direction. By the guidance of the fitting portions 6 and 7 on both sides on the diameter line in the X direction, the ball frame 2 and the moving frame 3 face each other in parallel, and the ball frame 2 moves while maintaining such a facing state. The frame 3 can be moved in the Y direction.

The driving mechanism A of the ball frame 2 with respect to the moving frame 3 is
The driving source is a piezo element 22 as an example of the electromechanical conversion element. However, any element having an electromechanical conversion function can be used. Piezo element 22
The piezo element 22 is mounted on the moving frame 3 on one end 22a side by providing a fixed portion 21 fixed to one end 22a of the It is fixed so that it can be displaced in the Y direction from the fixing part 21 as a starting point. However, this fixing method may be performed by various methods. For example, the moving frame 3 may be fixed to a step surface formed on the surface itself.
The other end 22b of the piezo element 22 is bonded to the drive shaft 14 in the Y direction by bonding or the like, and is displaced in the Y direction together with the piezo element 22 from the fixed portion 21 as a starting point.
The drive shaft 14 is supported by a pair of support members 15 provided integrally or fixed on the moving frame 3 and arranged in the Y direction so as to be guided in the displacement direction, and a portion between the support members 15 is a ball. By being frictionally fitted to the bearing hole 13 a of the bearing portion 13 of the frame 2, it is frictionally coupled to the bearing portion 13, and the displacement in the Y direction when the drive shaft 14 is driven by the piezo element 22 is ball through the bearing portion 13. The image is transmitted to the frame 2, and the ball frame 2 is driven in the Y direction to correct the camera shake in the Y direction.

The support mechanism for the movable frame 3 with respect to the fixed frame 4 is as follows.
The fitting portions 26 and 27 provided on both sides of the moving frame 3 and the fixed frame 4 on the diameter line in the Y direction are used. The fitting portion 27 is provided on a pair of bifurcated bearing pieces 31, 31 integrally arranged on the side of the moving frame 3 so as to be parallel to the plane of the moving frame 3 and to be arranged in the X direction. The guide shaft 32, which is parallel to the plane of the fixed frame 4 and fixed in the X direction and is oriented in the X direction, is fitted so that it can slide in the X direction. Fitting part 2
Reference numeral 6 denotes a bearing portion 33 provided integrally with a side portion of the moving frame 3 and having a bearing hole 33a parallel to the plane of the moving frame 3 and oriented in the X direction.
And a drive shaft 34 provided on the side of the fixed frame 4 in a direction perpendicular to the optical axis L so as to be slidable in the X direction. By the guidance of the fitting portions 26 and 27 on both sides on the diameter line in the X direction, the moving frame 3 and the fixed frame 4 face each other in parallel, and the moving frame 3 is fixed while maintaining such a facing state. The frame 4 can be moved in the X direction.

Drive mechanism B for moving frame 3 with respect to fixed frame 4
Uses a piezo element 42 as an example of an electromechanical conversion element as a driving source. However, any element having an electromechanical conversion function can be used. A fixing portion 41 fixed to one end 42a of the piezo element 42 is provided, and the fixing portion 41 is integrally formed on or fixed to the fixing frame 4 to be fixed. So that it can be displaced in the X direction from the fixing part 41 as a starting point. However, this fixing method may be performed by various methods, and for example, it may be fixed to a step surface formed on the surface of the fixing frame 4 itself. The other end 42b of the piezo element 42 is connected to the drive shaft 34 oriented in the X direction by bonding or the like.
2 is displaced in the X direction with the fixed part 41 as a starting point. The drive shaft 34 is provided integrally on the fixed frame 4 or supported by a pair of fixed support members 35 arranged in the X direction so as to be guided in the displacement direction.
5 is friction-coupled to the bearing 33 by frictionally fitting the portion between the bearing holes 33a of the bearing 33 of the moving frame 3,
The displacement in the X direction when the drive shaft 34 is driven by the piezo element 42 is transmitted to the moving frame 3 via the bearing 33,
The moving frame 3 is driven in the X direction together with the ball frame 2 to correct the camera shake in the X direction.

The current position in the XY2 direction of the ball frame 2 as a reference for correcting camera shake by the drive mechanisms A and B is provided at one position on the diameter line in the X direction and one position on the diameter line in the Y direction of the ball frame 2. LEDs 51 and 52 are provided, for example, LE
The position of D51 in the X direction is set to the corresponding PS on the fixed frame 4.
The position information detected by the D53 (semiconductor position detector) and the position of the LED 54 in the Y direction are indicated by the corresponding fixed frame 4.
Judgment is performed from the position information detected by the PSD 54 above, and the camera shake correction is performed while feeding back the information of the detected current position. Each drive mechanism A, B from the optical axis L
The distance to is almost equal.

In the first embodiment, in particular, in the driving mechanism A, the portion of the support member 15 on the moving frame 3 on the piezo element 22 side from the portion facing the piezo element 22 to the moving frame 3 of the piezo element 22 is moved. A cover wall 61 extending to the fixing portion 21 and covering the piezo element 22 is formed. The driving mechanism B also extends from the portion of the support member 35 on the fixed frame 4 on the piezo element 42 side facing the piezo element 42 to the fixing portion 41 of the piezo element 42 to the fixed frame 4, and moves the piezo element 42. A covering wall 62 is formed. These covering walls 6
As for the reference numerals 1 and 62, specific conditions for how and how to cover the exposed portions of the piezo elements 22 and 42 may be set as necessary.

As described above, the piezo elements 22 and 42 are supported by the supporting members 15 and 3 on the moving frame 3 and the fixed frame 4 as the supporting base.
The piezo elements 22 and 42 are covered by the covering walls 61 and 62 extending from the base member 5 to the fixing portions 21 and 41, so that the piezo elements 22 and 42 cover the entire length including around the joint with the driving shafts 14 and 34 as the driving members. Since they are covered and protected by 61 and 62, the stiffness of the piezo elements 22 and 42 and the connection between them and the drive shafts 14 and 34 is improved, and early breakage due to the influence of external force or vibration is eliminated. Is done.

Furthermore, the covering walls 61 and 62 are
Since the number of parts does not increase because the components are integrated with the components 5 and 35, the cost does not increase.

As shown in FIG. 1, the surrounding walls 61 and 62 of the first embodiment are
2 and 42 are formed in a tunnel shape to cover between the ball frame 2 and the moving frame 3, so that the entire length of the piezo elements 22 and 42 including the coupling portion between the piezo elements 22 and 42 and the drive shafts 14 and 34 is provided. Since the entire surrounding area is covered, the protection function of the covering walls 61 and 62 is further increased, and the durability is further improved.

The covering walls 61 and 62 are fixed to the fixing portions 21 and 4.
1 may be integrally formed, or a driving member may be coupled to the other end of the electromechanical conversion element having one end fixed on the base, and the moving member driven by the driving member may be moved by the displacement of the electromechanical conversion element. The present invention can be applied to any driving device that drives.

In this embodiment, an elastic member 63 having high thermal conductivity is provided in the space around the piezo elements 22 and 42 formed by the moving frame 3 and the fixed frame 4 serving as the base and the covering walls 61 and 62. It has been filled. Such an elastic member 63
Examples include silicone rubber for heat diffusion. As described above, the space around the piezo elements 22, 42 between the movable frame 3 or the fixed frame 4 and the covering walls 61, 62 is filled with the elastic member 63, so that the vibration of the piezo elements 22, 42 is absorbed. Therefore, the influence of the vibration of the piezo elements 22 and 42 can be reduced, and the durability and driving accuracy can be further improved. Moreover, since the elastic member 63 is made of a material having good heat conductivity, heat conduction from the piezo elements 22 and 42 to the covering walls 61 and 62 is promoted, and heat dissipation is improved. In this case, the covering walls 61 and 62 are
Desirably, it is a metallic member integral with 35.

The support members 15 and 35 are connected to the drive shaft 1.
It is also characterized in that the cover wall is formed on two sides of the electromechanical conversion element which are provided at two places in the displacement direction of the electromechanical transducers 4 and 34.

As described above, the support members are provided at a plurality of positions in the displacement direction of the drive member, and the cover walls 61 and 62 are provided on the side opposed to the piezo elements 22 and 42.
Are integrally formed, and the support members 15 and 35 are
4, a bearing member 13 which is a moving member driven by the displacement of
While supporting the drive shafts 14 and 34 at an optimum position in consideration of the positional relationship between the frame 33 and the frame 2 and the moving frame 3 integrated therewith, the piezo elements 22 and 4 of the support members 15 and 35 are supported.
By providing the covering walls 61 and 62 on the side opposite to 2, the above-described configuration and operation and effect can be satisfied regardless of the plurality of supporting members 15 and 35.

(Embodiment 2) In Embodiment 2, as shown in FIG. 2, the fixing portions 21, 41 fixed to one ends of piezo elements 22, 42, which are driving sources, are the case of Embodiment 1. Are fixed to the moving frame 3 and the fixed frame 4 as described above, and from the portions of the support members 15 and 35 on the moving frame 3 and the fixed frame 4 facing the piezo elements 22 and 42,
This embodiment differs from the first embodiment in that the piezo elements 22 and 42 are formed in a concave groove shape extending from the both sides on the moving frame 3 and the fixed frame 4 so as to extend to 41. Since other configurations are the same as those of the first embodiment, the same members are denoted by the same reference numerals, and redundant description will be omitted.

As described above, the covering walls 61 and 62 covering the piezo elements 22 and 42 are moved from the support members 15 and 35 of the moving frame 3 and the fixed frame 4 on the moving frame 3 and the fixed frame 4 of the piezo elements 22 and 42. With the groove-shaped covering walls 61 and 62 extending to the fixing portions 21 and 41, the piezo elements 22 and
Piezo element 2 including a connection portion between drive shaft 42 and drive shafts 14 and 34
Covering the entire length of 2, 42 from both sides, covering walls 61, 6
2, the covering walls 61 and 62 are formed in a simple shape with concave grooves while ensuring the functions of protection, heat dissipation, and vibration suppression, thereby facilitating manufacture and reducing cost. And the piezo elements 22, 42 and the drive shaft 1
Exposure of both 4 and 34 is convenient for inspection and maintenance.

[0037]

According to one aspect of the present invention, the electromechanical transducer and its drive are protected because the entire length of the electromechanical transducer, including around the joint with the driving member, is covered and protected by the covering wall. The rigidity of the connecting portion with the member is improved, and it is possible to prevent the device from being damaged early due to an external force or vibration. In addition, it is easy to dissipate heat generated when the electromechanical transducer is driven by the cover wall, and it is possible to suppress the influence of heat on the electromechanical transducer and the surroundings, and to prevent the occurrence of drive deviation. In addition, since vibration when the electromechanical transducer is driven can be suppressed, both the durability and the driving accuracy are improved. Further, since the covering wall is integral with the supporting member and the number of parts does not increase, it does not cause an increase in cost.

According to another feature of the invention, the covering wall is tunnel-shaped and covers the entire area around the entire length of the electromechanical transducer element including the connection between the electromechanical transducer element and the driving member. The protection function is further increased, and the durability is improved accordingly.

According to still another feature of the present invention, since the covering wall has a concave groove shape, the entire length of the electromechanical transducer including the connecting portion between the electromechanical transducer and the driving member is covered from both sides. Since the covering wall has a simple form in which the covering wall has a concave groove shape while securing the protection function by the covering wall, it is easy to manufacture and the cost can be reduced accordingly, and the electromechanical conversion element and the drive Exposing both members is convenient for inspection and maintenance.

According to another feature of the present invention, the elastic material filled in the space around the electromechanical transducer between the base and the covering wall absorbs and attenuates the vibration of the electromechanical transducer, The effect of the vibration of the electromechanical transducer can be reduced, and the durability and driving accuracy can be improved. In addition, since the elastic member has good heat conductivity, heat conduction from the electromechanical transducer to the covering wall is promoted, and heat radiation characteristics are improved.

According to still another feature of the present invention, while the driving member is supported by the plurality of support members at an optimum position in consideration of the positional relationship with the moving member that follows the driving member, the electric power of the plurality of support members is reduced. By providing the covering wall on the side facing the mechanical conversion element, it is possible to satisfy the above-described configuration and operation and effect irrespective of the plurality of support members.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a lens-system image stabilizing apparatus employing a driving device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing a lens-system image stabilizing device employing a driving device according to a second embodiment of the present invention.

FIG. 3 is an exploded perspective view showing a lens-system image stabilizing device employing a conventional driving device.

[Explanation of symbols]

 2 Ball frame 3 Moving frame 4 Fixed frame 6, 7, 26, 27 Fitting part 14, 34 Drive shaft 15, 35 Support member 21, 41 Fixed part 22, 42 Piezo element 22a, 42a One end 22b, 42b Other end 61, 62 covering wall 63 elastic member

Claims (5)

[Claims] An electromechanical transducer, a base member to which one end of the electromechanical transducer is fixed, a driving member coupled to the other end of the electromechanical transducer, and displaced from the fixed portion together with the electromechanical transducer. An electromechanical transducer of the support member, comprising: a support member fixed to the base and supporting the drive member so as to guide the drive member in the displacement direction; and a moving member driven by the drive member. From the part opposite to
A drive device, wherein a cover wall extending to a fixing portion of the electromechanical transducer to the base is formed to cover the electromechanical transducer. 2. An electromechanical transducer, a fixed part coupled to one end of the electromechanical transducer, and coupled to the other end of the electromechanical transducer and displaced from the fixed part together with the electromechanical transducer from the fixed part. A drive member, a base holding the fixed portion to hold the electromechanical transducer and the drive member, a support member fixed to the base, and supporting the drive member so as to guide the drive member in the displacement direction; And a moving member driven by a member, wherein:
A driving device, wherein a tunnel-shaped covering wall extending to the fixing portion and covering an electromechanical transducer with the base is formed. 3. An electromechanical transducer, a fixed part coupled to one end of the electromechanical transducer, and coupled to the other end of the electromechanical transducer and displaced with the electromechanical transducer from the fixed part as a starting point. A drive member, a base holding the fixed portion to hold the electromechanical transducer and the drive member, a support member fixed to the base, and supporting the drive member so as to guide the drive member in the displacement direction; And a moving member driven by a member, wherein:
A driving device, wherein a groove-like covering wall extending to the fixing portion and covering the electromechanical transducer from both sides on the base is formed. 4. The drive device according to claim 1, wherein a space around the electromechanical transducer formed by the base and the cover wall is filled with an elastic material having high thermal conductivity. 5. The device according to claim 1, wherein the support member is provided at a plurality of positions in the displacement direction of the drive member, and the cover wall is formed on a side of the support member facing the electromechanical transducer. The driving device according to claim 1.