JP2009247163A - Driving device and lens driving device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a driving device which enables connection of a lead wire supplying voltage to an electromechanical transducing element working as a driving source for axial move at a spot separated from an operation portion in a simplified arrangement to facilitate handling of the lead wire that does not hamper the move of a driven member, thereby: improving operation stability; facilitating assembling; and reducing costs. <P>SOLUTION: With a friction engagement member 13 disposed on a retaining member 11, a drive member 12 is set longitudinally along the retaining member 11 so that one end of the drive member 12 is supported in a state of friction engagement. The electromechanical transducing element 14 is fixed to the other end face of the drive member 12, and the driven member 15 is fixed to the other end face of the electromechanical transducing element 14. The drive member 12 has an external face at least having conductivity, and at least a fixed end external face (peripheral face or end face) facing the electromechanical transducing element 14 is close to a surface bearing one electrode 14a and is connected electrically to one electrode 14a via a conductive connection means 16. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention uses an electro-mechanical conversion element as a drive source for moving a driven object in its expansion / contraction direction, and controls the relative magnitude of the inertial force of the driven object and the frictional engagement force of the support portion by pulse control. The present invention relates to a driving device that can reciprocate an object in the axial direction and a lens driving device that drives a lens in the optical axis direction.

  Conventional lens drive devices include a lens frame that holds the lens, a guide shaft that guides the lens frame in the optical axis direction, a spring that biases the lens frame in one direction in the optical axis direction, and a part of the lens frame that cannot be rotated. A nut having a female screw held on the motor, a motor fixed to the base, and the like. As described above, the configuration using the motor as the drive source has a problem that the number of parts is large, the structure is complicated, the assembly is difficult, the cost is high, and the lens drive is delayed.

  Thus, for example, Patent Documents 1 to 5 propose using a piezoelectric element as a driving source of the lens driving device. Conventional drive devices using piezoelectric elements are generally known in the impact method (IDM), stick / slip method, smooth impact method (SIDM), and the like.

  The lens driving device of Patent Document 1 is configured by fixing a driving member to a piezoelectric element, frictionally engaging a driven member to the driving member, and inputting a driving pulse for expanding and contracting the piezoelectric element to reciprocate the driving member. Thus, the driven member is moved relative to the driving member.

  In the lens driving device of Patent Document 2, as a means for improving the efficiency of connecting lead wires of a piezoelectric element, a connection socket configured to be attachable to the piezoelectric element and a connection position of a wiring board made of a conductor are provided. It is the structure provided with the extending contact piece.

  The lens driving device of Patent Document 3 includes a driving shaft fixed to one end of an electro-mechanical conversion element, and a lens barrel frictionally engaged with the driving shaft by a pressure contact spring and a friction plate. When a pulse voltage is applied to the electro-mechanical conversion element, the electro-mechanical conversion element expands and contracts and the drive shaft changes to move the lens barrel frictionally engaged with the drive shaft.

  The lens driving device disclosed in Patent Document 4 has an input terminal that is connected to an electrode of a piezoelectric element and is provided at a position of a non-expandable portion as a means for reducing the influence of a connection portion of a wiring member connected to the piezoelectric element on the operation of the piezoelectric element. And the printed wiring board is soldered to the input terminal at the non-stretched position.

  In each of the above four examples, one end surface of the piezoelectric element in the expansion / contraction direction is fixed to the fixing member, the driving member is fixed to the other end surface, and the driven member is frictionally engaged with the driving member. Structure.

Japanese Patent No. 2633066 JP 2007-267538 A JP 7-274544 A JP 2007-274777 A

  However, it is considered that the driving device using the piezoelectric element of Patent Documents 1 to 4 is very difficult to process the lead wire for supplying voltage to the piezoelectric element as the camera module is downsized.

  In addition, the lens driving device using the piezoelectric element described in the embodiment according to Patent Document 1 has a problem that it is difficult to electrically connect the piezoelectric element and to manufacture the lens. When the driving device is downsized, the piezoelectric element is also used with a small size. To connect a lead wire extending from the piezoelectric element, tweezers are used to solder the positive electrode and the negative electrode of the piezoelectric element. It becomes. Such a connection work of the lead wires of the piezoelectric element is a very fine work, and the workability is very poor.

  Further, in the lens driving device using the piezoelectric element described in the embodiment according to Patent Document 2, the voltage supply means to the electro-mechanical conversion element includes a connection socket, a contact piece 1, a contact piece 2, and a support member. Since at least three types and four parts are required, there is no cost advantage, and the structure goes against the downsizing.

  Further, in the lens driving device using the piezoelectric element described in the embodiment according to Patent Document 3, two lead wires for supplying a voltage to the electro-mechanical conversion element are arranged close to each other and the electro-mechanical conversion element is arranged. Since it is attached to the upper surface, it is thought that it is very difficult to process the lead wires.

  Further, in the lens driving apparatus using the piezoelectric element described in the embodiment according to Patent Document 4, the apparatus is miniaturized, the piezoelectric element is further miniaturized, and the non-stretchable portion with respect to the entire length of the piezoelectric element The ratio of the occupancy is very small, the assembly workability is poor, and the contacts are minute, so there is a risk of causing contact failure due to the influence of vibration of the piezoelectric element.

  The present invention has been made in view of the above circumstances, and its object is to connect at least one lead wire for supplying a voltage to the electromechanical conversion element to a non-operation member and Ease of processing and simplification of structure can be achieved, the reaction force of the lead wire does not hinder the mobility of the driven member, and the operational stability is improved, the structure is simple and easy to assemble, and the cost It is an object of the present invention to provide a driving device that leads to reduction and a lens driving device that drives a lens in the optical axis direction.

  The drive device according to the present invention includes a holding member, a drive member, a friction engagement member that is provided on the holding member and supports the drive member in a friction engagement state, and an end surface of the drive member in a telescopic direction. An electro-mechanical conversion element having an end surface fixed thereto, and a driven member fixed to the other end surface of the electro-mechanical conversion element, wherein the driving member has at least an outer surface conductive, and the outer surface Is electrically connected to one electrode of the electromechanical conversion element by a conductive connecting means.

  According to the driving device of the present invention, when a control voltage is applied to the lead wire, the electromechanical conversion element expands and contracts in the horizontal direction by the application of the control voltage, and the quick extension and the slow contraction are alternately performed. When the driven member is moved by a small step in the direction of the friction engagement member and the slow extension and the rapid contraction are alternately performed, the driven member is moved by a small step in a direction away from the friction engagement member. .

  Further, according to the driving device of the present invention, the electrical connection between one of the electrodes and the driving member only needs to be pointed to the solder, and the electrical connection by the point-like conductive connecting means (for example, soldering) is realized. The drive member can be assembled to the frictional engagement member without a lead wire, and the lead wire for supplying voltage to one of the electrodes can be attached at any part of the drive member. In addition, since it is possible to make a connection with a member that is electrically connected to the drive member, the lead wire can be connected at a position far away from the electro-mechanical conversion element, and the electrical connection to one electrode can be performed. Connection can be realized.

In the drive device having the above-described configuration, the friction engagement member is configured such that at least a part of an engagement support surface that frictionally supports the drive member has conductivity. -It is preferably electrically connected to one electrode of the mechanical transducer.
According to this configuration, since the lead wire can be attached to the fixing member (friction engagement member), the movement performance with respect to the driven member due to the reaction force of the lead wire is not hindered, and it contributes to the improvement of the operation stability. In addition, there is no concern of problems such as disconnection.

In the drive device having the above-described configuration, the friction engagement member includes an engagement fixing member provided on the holding member and having a recess for receiving and guiding the drive member, and a spring member fixed to the engagement fixation member. Thus, at least one of the engagement fixing member and the spring member is made of a conductive material, and is electrically connected to one electrode of the electromechanical conversion element via the drive member.
According to this configuration, the friction engagement member that is electrically connected to the drive member can be simply configured, and the lead wire can be connected to the upper surface of the engagement fixing member or the spring member, so that a stable voltage supply can be achieved. Yes.

In the driving device configured as described above, at least a part of the outer surface of the driven member has conductivity, and a part of the outer surface and the other electrode of the electromechanical conversion element are electrically conductive connecting means. It is preferable that a lead wire is connected to a part of the outer surface of the driven member by a conductive connecting means.
According to this configuration, it is possible to realize the attachment of the lead wire at a site away from the electro-mechanical conversion element and at a site where soldering is easily performed.

In the driving device configured as described above, at least a part of the outer surface of the driven member has conductivity, and a part of the outer surface and the other electrode of the electromechanical conversion element are connected by a conductive connecting means. Furthermore, the guide member made of a conductive material provided on the driven member and electrically connected to a part of the outer surface, and at least the surface of the holding member in contact with the guide member is made electrically conductive. It is preferable that it is connected to.
According to this configuration, it is possible to realize the attachment of the lead wire at a site away from the electro-mechanical conversion element and at a site where soldering is easily performed.

A lens driving device according to the present invention includes the driving device according to any one of claims 1 to 5 as lens driving means for driving a lens in an optical axis direction.
According to the lens driving device of the present invention, when a control voltage is applied to the lead wire, the electromechanical conversion element expands and contracts in the horizontal direction by applying the control voltage, and alternately performs rapid expansion and slow contraction. When the driven member is moved by a small step in the direction of the friction engagement member, and when the slow extension and the rapid contraction are alternately performed, the driven member is moved by a small step in a direction away from the friction engagement member. To do. Thereby, the lens can be driven in the optical axis direction. According to the lens driving device of the present invention, the movement speed of the lens (lens frame) in the optical axis direction can be increased or decreased while the structure is simplified and reduced in size, and the time required for the movement is shortened. The lens feed amount (movement amount) can be finely adjusted.

  According to the driving device and the lens driving device configured as described above, at least one of the lead wires for supplying a voltage to the electromechanical conversion element can be connected to a non-operational member, facilitating the lead wire processing and simplifying the structure. It can be achieved, and the reaction force of the lead wire does not hinder the mobility of the driven member, the operation stability is improved, the structure is simple and easy to assemble, and the driving device and the lens that lead to cost reduction are lighted. A lens driving device that drives in the axial direction can be provided.

  Hereinafter, a drive device according to an embodiment of the present invention will be described with reference to the accompanying drawings.

(First embodiment)
1 to 4 are views showing a driving apparatus according to the first embodiment of the present invention.
In the driving device 1A, the friction engagement member 13 is fixed on the holding member 11, and the driving member 12 is fixed to one end surface in the expansion / contraction direction of the electromechanical conversion element 14 and driven to the other end surface. An assembly in which the member 15 is fixed is set as a horizontal axis so as to follow the holding member 11, and a portion near the base end of the drive member 12 is supported in a friction engagement state by the friction engagement member 13. In addition, two lead wires 17 and 19 for supplying a control voltage to the electrodes 14a and 14b on the upper and lower surfaces of the electro-mechanical conversion element 14 are provided.

An outline of the operation of the drive device 1A will be described (details will be described later).
When a pulsed control voltage is applied to the lead wires 17 and 19 and the electro-mechanical conversion element 14 expands and contracts in the horizontal direction by the application of the control voltage, and rapid extension and slow contraction are performed alternately, the driven When the member 15 is moved by a small step in the direction of the friction engagement member 13 and the slow extension and the rapid contraction are alternately performed, the driven member 15 is moved by a small step in a direction away from the friction engagement member 13. To do.

The holding member 11 is a so-called base, and in this embodiment, the holding member 11 may be configured using either a conductive material or a non-conductive material.
The driving member 12 is a so-called horizontal slide shaft, and is made of CFRP (carbon fiber composite material) having a small mass to increase the inertial force, or a carbon-based sintered body, or another conductive material having a small mass suitable for the shaft material. It is selected and formed into a round bar shape.
The friction engagement member 13 is a so-called linear guide bracket for the drive member 12 and horizontally supports the drive member 12 in the friction engagement state. In this embodiment, the friction engagement member 13 includes an engagement fixing member 13a and a spring member 13b. The engagement fixing member 13a is fixed to the upper surface of the holding member 11, and has a recess (V-shaped recess or semi-cylindrical recess) 13a ′ that receives and guides the drive member 12. The spring member 13b is covered with the driving member 12 received by the concave portion (V-shaped concave portion or semi-cylindrical concave surface portion) 13a ', and is fixed to the engaging fixing member 13a by a fastening tool (child screw) 24 and fixed to the driving member 12. Apply frictional engagement force.
The electro-mechanical conversion element 14 is a piezoelectric element that expands and contracts slightly when a voltage is applied. Here, the electro-mechanical conversion element 14 has a rectangular parallelepiped shape and includes electrodes 14a and 14b on the upper and lower surfaces. One of the electrodes 14a and 14b is a positive electrode and the other is a negative electrode. The electromechanical conversion element 14 has a function of expanding and contracting when a control voltage is applied between the electrodes 14a and 14b.
The driven member 15 is a member to be moved, and is formed to be larger or made of a material having a larger mass than the driving member 12 and the electro-mechanical conversion element 14 so that an operation principle using inertial force can be realized. Therefore, the driving member 12 and the electromechanical conversion element 14 are formed so as to be considerably larger than the total weight.

As an electrical connection structure between one electrode (lower surface side electrode) 14a and the lead wire 17, in this embodiment, the drive member 12 made of a conductive material and one electrode 14a of the electromechanical conversion element 14 are electrically conductive. The spring member 13b is made of a metal material having elasticity and conductivity, and the lead wire 17 is conductively connected to the upper surface of the spring member 13b. It is attached by means (soldering or conductive adhesive) 18. The conductive connection means 16 is provided when the drive member 12 and the electromechanical conversion element 14 are fixed.
Accordingly, the lead wire 17 is not attached to the electrode 14a on the lower surface of the electromechanical conversion element 14 where it is difficult to attach the lead wire 17, and the lead wire 17 is attached at a position that is far away from the electrode 14a and is easy to attach. However, the electrode 14a and the lead wire 17 are electrically connected. Thereby, since the lead wire 17 also moves simultaneously due to the expansion and contraction of the electromechanical conversion element 14, the concern that troubles such as hindrance to the operation due to the reaction force of the lead wire and disconnection of the lead wire are eliminated.

  As an electrical connection structure between the other electrode (upper surface side electrode) 14b of the electromechanical conversion element 14 and the lead wire 19, in this embodiment, the lead wire 19 is electrically connected to the other electrode 14b positioned on the upper surface. Are connected by the sex connection means 20.

The operation of the driving device 1A will be described.
When the pulsed control voltage applied to the lead wires 17 and 19 rises instantaneously, and the electro-mechanical conversion element 14 expands instantaneously in the horizontal direction, the inertial force of the driven object 15 is increased. Since the frictional engagement force by the frictional engagement member 13 is greater, the driven member 15 stops at the stationary position. At this time, the position where the frictional engagement member 13 holds the drive member 12 is at the electromechanical conversion element 14. It shifts to a state where it has moved a small step in the approaching direction. Then, the fall of the pulsed control voltage applied to the lead wires 17 and 19 is performed slowly over time, so that when the electromechanical conversion element 14 slowly contracts in the horizontal direction, Since the inertial force of the driven object 15 is smaller than the frictional engagement force by the frictional engagement member 13, the driven member 15 moves in the direction of the frictional engagement member 13 by the size of the contraction of the electromechanical conversion element 14.
Therefore, when the control voltage applied to the lead wires 17 and 19 is one in which the electromechanical conversion element 14 alternately performs instantaneous extension and slow contraction in the horizontal direction, the driven member 15 is rubbed. It moves in the direction of the engaging member 13.

Further, the rise of the pulsed control voltage applied to the lead wires 17 and 19 is performed slowly over time, so that when the electro-mechanical conversion element 14 is slowly extended in the horizontal direction, the driven Since the inertial force of the object 15 is smaller than the frictional engagement force by the frictional engagement member 13, the driven member 15 is moved by the size of the extension of the electromechanical conversion element 14. At this time, the frictional engagement member 13 is driven. The position where the member 12 is held does not change. Then, the falling of the pulsed control voltage applied to the lead wires 17 and 19 is performed instantaneously. As a result, when the electromechanical transducer 14 contracts instantaneously in the horizontal direction, the driven object 15 Since the inertial force is larger than the frictional engagement force by the frictional engagement member 13, the driven member 15 stops at the stationary position. At this time, the drive member 12 holds the drive member 12 at the position where the frictional engagement member 13 is held. It shifts to a state where it moves by a small step in a direction away from the friction engagement member 13.
Therefore, when the control voltage applied to the lead wires 17 and 19 is one in which the electromechanical conversion element 14 alternately performs slow expansion and instantaneous contraction in the horizontal direction, the driven member 15 is subjected to friction. A small step moves in a direction away from the engaging member 13.
When the positive and negative of the electrodes 14a and 14b of the electromechanical conversion element 14 are reversed, the control voltage applied to the lead wires 17 and 19 becomes a negative value.

  According to the driving apparatus 1A of this embodiment, the electromechanical conversion element 14 is used as a driving source for moving the driven object 15 in the expansion and contraction direction, and the inertial force of the driven object 15 and the frictional engagement force of the frictional engagement member 13 are used. It is possible to reciprocate the driven object 15 in the axial direction by controlling the relative magnitude of.

  According to the drive device 1A of this embodiment, since one electrode 14a provided on the opposite surface of the electromechanical conversion element 14 and the outer surface having conductivity of the drive member 12 are close to each other, For the electrical connection between the electrode 14a and the driving member 12, it is only necessary to point the solder, and the electrical connection by the point-like conductive connection means (for example, soldering) 16 is realized. The conductive connecting means (for example, soldering) 16 can be installed before the drive member 12 is assembled to the friction engagement member 13. For this reason, the drive member 12 can be assembled to the friction engagement member 13 without the lead wire 17 being provided, and the assembly is facilitated. After the assembly, the lead wire 17 for supplying a voltage to the one electrode 14a is attached to a member (in this embodiment, the spring member 13b) that is electrically connected to the drive member 12. Therefore, the lead wire can be connected at a position far away from the electro-mechanical conversion element 14, and electrical connection to one electrode 14a can be realized. If the electro-mechanical conversion element 14 is a rectangular parallelepiped and is provided with two electrodes distributed on the upper and lower surfaces, the lower electrode on which the lead wire is difficult to be provided is selected as the one electrode 14a. The connecting operation of the lead wire 19 to the other electrode 14 b can be easily performed on the upper surface of the driving member 12.

  According to the drive device of this embodiment, the lead wire 17 can be connected to the upper surface position of the member 13 that does not move at a position far away from the electro-mechanical conversion element 14, and electrical connection to one electrode 14a is achieved. Since it can be realized and attached to the member 13 that does not move, it does not hinder the movement performance with respect to the driven member 15 due to the reaction force of the lead wire 17 and contributes to the improvement of operational stability, and there is a problem such as disconnection. There are no concerns that arise.

  According to the drive device of this embodiment, the friction engagement member 13 that is electrically connected to the drive member 12 can be simply configured, and the connection work of the lead wire 17 can be performed with respect to the upper surface of the engagement fixing member 13a or the spring member 13b. Can be performed stably.

  According to the driving device of this embodiment, since the lower electrode 14a is selected as one electrode 14a and is connected to the friction engagement member 13 by point-shaped soldering, the electromechanical conversion element 14 is very small. However, since the electrode on the upper surface side of the electromechanical conversion element 14 can be selected as the other electrode 14a, the lead wire 19 can be easily connected by the conductive connecting means 20.

(Second Embodiment)
5 and 6 are diagrams showing a moving device according to the second embodiment of the present invention. The drive device 1B includes an assembly including a holding member 11, a drive member 12, a friction engagement member 13, an electro-mechanical conversion element 14, and a driven member 15 according to the first embodiment. Is the same. Further, the electrical connection structure between one electrode (lower surface side electrode) 14a and the lead wire 17 is the same as that of the driving apparatus 1A of the first embodiment. Further, when a control voltage is applied to the lead wires 17 and 19, the electromechanical conversion element 14 expands and contracts, and the relative magnitude between the inertial force of the driven object and the frictional engagement force by the frictional engagement member at this time The operating principle by which the driven object can be reciprocated in the axial direction by controlling the height is the same as in the case of the driving apparatus 1A of the first embodiment. Therefore, detailed description of these components is omitted.

  In the driving device 1B, as an electrical connection structure between the other electrode (upper surface side electrode) 14b and the lead wire 17, the driven member 15 is made of a conductive material, and the upper surface and the electromechanical conversion element 14 are connected. In the first embodiment, the first electrode 14b is connected to the driven member 15 by the conductive connecting means 21 and the lead wire 19 is connected to the driven member 15 by the conductive connecting means 20. This is different from the case of the driving device 1A. In this embodiment, it is sufficient that the driven member 15 has at least an upper surface (a part of the outer surface) having conductivity.

  According to the driving device 1B of the second embodiment, the other electrode 14b of the electro-mechanical conversion element 14 and the driven member 15 can be electrically connected by the point-like conductive connection means 21, and further, The lead wire 19 for supplying a voltage to the other electrode 14b can be attached to the upper surface of the sufficiently large driven member 15 by soldering, not to the electromechanical conversion element 14 which is a minute member. Accordingly, it is possible to realize the lead wire attachment at a site away from the electro-mechanical conversion element 14 and at a site where soldering can be easily performed.

(Third embodiment)
7 and 8 are views showing a driving apparatus according to the third embodiment of the present invention. The drive device 1C includes an assembly including a holding member 11, a drive member 12, a friction engagement member 13, an electromechanical conversion element 14, and a driven member 15 according to the first embodiment. Same as 1A. Further, the electrical connection structure between one electrode (lower surface side electrode) 14a and the lead wire 17 is the same as that of the driving apparatus 1A of the first embodiment. Further, when a control voltage is applied to the lead wires 17 and 19, the electromechanical conversion element 14 expands and contracts, and the relative magnitude between the inertial force of the driven object and the frictional engagement force by the frictional engagement member at this time The operating principle by which the driven object can be reciprocated in the axial direction by controlling the height is the same as in the case of the driving apparatus 1A of the first embodiment. Therefore, detailed description of these components is omitted.

  In the driving device 1C, as an electrical connection structure between the other electrode (upper surface side) 14b and the lead wire 17, at least the outer surface of the driven member 15 has conductivity, and the outer surface and the electromechanical conversion are provided. The other electrode 14 b of the element 14 is connected by the conductive connection means 21, and a conductive floor plate 23 is provided on an area surface corresponding to at least the driven member 15 of the holding member 11. Since the lower surface of the driven member 15 is received by the provided guide member 22 made of a conductive material so as to be relatively slidable, the floor plate 23 and the other electrode 14b are electrically connected. The lead wire 19 is connected to the conductive connecting means 20. Note that the surface of the same area may be subjected to conductive plating or painting instead of the floor plate 23.

  According to the driving device 1C of the third embodiment, the electrical connection between the other electrode 14b of the electromechanical conversion element 14 and the driven member 15 is performed, and the driven member 15 and the holding member are further connected. 11 is electrically connected between at least the driven member 15 and the corresponding area surface, and the lead wire 19 for supplying a voltage to the other electrode 14b is connected to the electro-mechanical conversion element 14 which is a minute member. However, it can be attached to the upper surface of the sufficiently large holding member 11 by soldering. Accordingly, it is possible to realize the lead wire attachment at a site away from the electro-mechanical conversion element 14 and at a site where soldering can be easily performed. Further, since the lead wire 19 also moves simultaneously due to the expansion and contraction of the electromechanical conversion element 14, the concern that troubles such as hindrance to the operation due to the reaction force of the lead wire and disconnection of the lead wire are eliminated.

FIG. 9 is a diagram showing a lens driving device 2 that is a combination of the lens holding guide device 30 and the driving device 1A of the first embodiment. The lens holding guide device 30 includes a lens holder 31 that holds the lens G and guides the lens G in the direction of the optical axis L in a floating state. That is, the pair of guide brackets 32 and 33 projecting from the lens holder 31 on both sides are engaged and guided by the guide columns 34 and 35 and are coiled around the guide pins 37 erected from the bracket 36. 38 is compressed by an upper pressing member (not shown) and biased downward. In the lens holding guide device 30, a joint pin 39 protruding from one side surface is located in a vertical plane with respect to the optical axis L, and a drive device 1 </ b> A is provided below the joint pin 39.
In the driving device 1A, the axis of the assembly of the driving member 12, the electro-mechanical conversion element 14, and the driven member 15 exists in a vertical plane with respect to the optical axis L and passes at a right angle below the articulation pin 39. It is equipped as such.
In this embodiment, the upper surface of the driven member 15 of the driving apparatus 1A is an inclined surface 15a that descends toward the overhanging end, and the connecting pin 39 is placed on the inclined surface 15a.

According to the lens driving device 2 of this embodiment, when a control voltage is applied to the lead wires 17 and 19 so that the electromechanical conversion element 14 performs rapid extension and slow contraction alternately, Since the driving member 15 moves in the direction of the friction engagement member 13 and the connecting pin contact level of the inclined surface 15a is lowered, the lens holder 31 is lowered by the weight of the lens holder 31 and the bias of the coil spring 38.
Further, when the electromechanical conversion element 14 performs slow extension and rapid contraction alternately, the driven member 15 moves away from the friction engagement member 13, and the connecting pin of the inclined surface 15a is moved. At this time, the inclined surface 15a causes a wedge action to lift the connecting pin 39 against the weight of the lens holder 31 and the bias of the coil spring 38. Accordingly, the lens holder 31 is raised.

  According to the lens driving device 2 of this example, since the driving device 1A of the first embodiment is used, the effects of the driving device 1A are obtained, and in addition, the structure is simple and easy to assemble, and the cost is reduced. It is possible to provide a lens driving device that produces effects such as reduction.

(Other embodiments and modifications)
The first to third embodiments and examples according to the present invention have been described with reference to the drawings. However, the present invention is not limited to this, and various design changes and modifications can be made without departing from the gist. Process changes are possible, and such changes are included in the technical scope.

(About the drive member 12)
The drive member 12 is formed in a round bar shape in the above embodiment, but may be configured in a square bar shape or the like because it is a component that does not require the function of the rotating shaft. The drive member 12 is made of CFRP or the like, which is a conductive material having a small mass in the above-described embodiment, but may be any structure as long as at least the outer surface has conductivity. For example, a configuration in which the outer surface is plated in a rod shape from a non-conductive material having a small mass suitable for the shaft material may be used.

(About the friction engagement member 13)
The friction engagement member 13 may be configured to be electrically connected to one electrode 14a of the electro-mechanical conversion element 14 via the drive member 12, and the largest idea is that the drive member 12 is supported by friction engagement. It suffices that at least a part of the engaging support surface (through hole inner surface portion) to be electrically connected is electrically connected. In the above embodiment, the spring member 13b is made of a conductive material, the engagement fixing member 13a is made of a non-conductive material, and the lead wire 17 is attached to the spring member 13b. Conversely, the spring member 13b may be made of a non-conductive material, the engagement fixing member 13a may be made of a conductive material, and the lead wire 17 may be attached to the engagement fixing member 13a. Further, both may be made of a conductive material.

(About the driven member 15)
In the third embodiment, the other electrode 14 b of the electromechanical conversion element 14 and the floor plate 23 may be electrically connected via the driven member 15. Therefore, it is only necessary that at least the outer surface of the driven member 15 has conductivity. Further, the driven member 15 is preferably made of a conductive metal material (for example, a copper alloy) having a large mass, but even if the outer surface of a non-conductive material having a large mass is provided with conductive plating. good.

(About the holding member 11)
In the third embodiment, the holding member 11 may be made of a conductive material and the floor plate 23 may be eliminated. In this case, when the engaging and fixing member 13a is made of a conductive material, the holding member 11 and the engaging and fixing member 13a are insulated to prevent a short circuit between the lead wire 17 and the lead wire 19.
In the third embodiment, at least the outer surface of the driven member 15 has conductivity, and the outer surface and the other electrode 14b of the electromechanical conversion element 14 are connected by the conductive connecting means 21, and The floor plate 23 of the area surface corresponding to at least the driven member 15 of the holding member 11 has conductivity,
Since the lower surface of the driven member 15 is received by the guide member 22 made of a conductive material provided on the floor plate 23 so as to be relatively slidable, the floor plate 23 and the other electrode 14b are electrically connected. In addition, any structure may be used as long as the lead wire 19 is connected to the floor plate 23 by the conductive connecting means 20.

  The drive device and lens drive device of the present invention can speed up or slow down the movement speed of the lens (lens frame) in the optical axis direction while achieving simplification and downsizing of the structure, and the time required for movement can be reduced. Since it can be shortened and the feed amount (movement amount) of the lens can be finely adjusted, it can be applied as a drive device for a digital camera and is also useful as a drive device for other lens optical systems.

It is a perspective view of the drive device concerning a 1st embodiment of the present invention. It is a front view of the drive device of FIG. It is a disassembled perspective view of the drive device of FIG. FIG. 2 is an electro-mechanical conversion element of a main part of the drive device of FIG. 1. It is a perspective view of the drive device concerning a 2nd embodiment of the present invention. It is a front view of the drive device of FIG. It is a perspective view of the drive device concerning a 3rd embodiment of the present invention. It is a front view of the drive device of FIG. It is a perspective view which shows the lens drive device which combines a lens holding | maintenance guide apparatus and the drive device of 1st Embodiment.

Explanation of symbols

1A, 1B, 1C driving device (lens driving means)
2 Lens drive device 11 Holding member 12 Drive member 13 Friction engagement member 13a Engagement fixing member 13a 'Recess 13b Spring member 14 Electro-mechanical conversion element 14a One electrode 14b The other electrode 15 Driven member 16 Conductive connection means ( Soldering or conductive adhesive)
17 Lead wire 18 Conductive connection means (soldering or conductive adhesive)
19 Lead wire 20 Conductive connection means (soldering or conductive adhesive)
21 Conductive connection means (soldering or conductive adhesive)
22 Guide member 23 Base plate

Claims (6)

A holding member, a drive member, a friction engagement member provided on the holding member and supporting the drive member in a friction engagement state, and an electric member having one end face in an expansion / contraction direction fixed to an end face of the drive member A mechanical conversion element, and a driven member fixed to the other end surface of the electro-mechanical conversion element,
The drive member has at least an outer surface conductive, and the outer surface is electrically connected to one electrode of the electro-mechanical conversion element by a conductive connection means.
A drive device characterized by that. In the friction engagement member, at least a part of an engagement support surface that frictionally supports the drive member has conductivity, so that one of the electro-mechanical conversion elements is interposed via the drive member. Electrically connected to the electrode,
The drive device according to claim 1. The friction engagement member includes an engagement fixing member provided on the holding member and having a recess for receiving and guiding the driving member, and a spring member fixed to the engagement fixing member. And at least one of the spring members is made of a conductive material, and is electrically connected to one electrode of the electro-mechanical conversion element via the drive member,
The drive device according to claim 1, wherein the drive device is provided. At least a part of the outer surface of the driven member has conductivity, and a part of the outer surface and the other electrode of the electromechanical conversion element are connected by a conductive connection means, and A lead wire is connected to a part of the outer surface of the driven member by a conductive connecting means,
The drive device according to any one of claims 1 to 3, wherein the drive device is provided. At least a part of the outer surface of the driven member has conductivity, a part of the outer surface and the other electrode of the electromechanical conversion element are connected by a conductive connecting means, and the driven member A guide member made of a conductive material provided on the member and electrically connected to a part of the outer surface, and at least a surface of the holding member in contact with the guide member is electrically connected, and is electrically connected;
The drive device according to any one of claims 1 to 3, wherein the drive device is provided.   A lens driving device comprising the driving device according to claim 1 as lens driving means for driving the lens in the optical axis direction.

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