JP2020193687A - Spring member, actuator and lens driving device - Google Patents

Abstract

To provide a spring member that can utilize characteristics of both a leaf spring and a viscoelastic body, and make efficient an operation to connect a movable body and a fixed body.SOLUTION: A spring member 10 has a leaf spring 8 and a viscoelastic body 9 fixed to the leaf spring 8, and the viscoelastic body 9 is arranged at a spring part 80 of the leaf spring 8. Characteristics of both the leaf spring 8 and the viscoelastic body 9 can, therefore, be utilized, so desired vibration characteristics are easily obtained. Further, the viscoelastic body 9 can suppress the leaf spring 8 from deforming large owing to an impact to become unable to restore itself into its original shape to have high impact resistance. The leaf spring 8 comprises arms 83 which extend spirally between a first fixed part 81 and a second fixed part 82, and also comprises a slit-shaped separation hole 89 provided between adjacent arms 83. The viscoelastic body 9 comprises a filling part 90 arranged in the separation hole 89 and a part protruding from the spring part 80 to both sides in a plate thickness direction LA (surface outward direction).SELECTED DRAWING: Figure 1

Description

The present invention relates to a spring member that connects a fixed body and a movable body, an actuator that vibrates the movable body with respect to the fixed body, and a lens driving device that moves a lens in the optical axis direction.

Some actuators include a fixed body and a movable body, and a magnetic drive mechanism for driving the movable body, and the movable body and the fixed body are connected by a connecting body. The actuator (linear actuator) of Patent Document 1 includes a spring member that connects the movable body and the fixed body, and a viscoelastic member that is arranged at a position where the movable body and the fixed body face each other in the vibration direction of the movable body. The viscoelastic member is a gel-like damper member such as a silicone gel. The movable body is oscillatedly supported by the spring member with respect to the fixed body. Further, when the movable body vibrates, the gel-like damper member is deformed in the crushing direction, so that the resonance between the spring member and the movable body is suppressed. As a result, excessive vibration of the movable body can be suppressed, and collision between the movable body and the fixed body can be suppressed.

Japanese Unexamined Patent Publication No. 2016-032417

In Patent Document 1, the movable body and the fixed body are connected by using both the spring member which is an elastic member and the gel-like damper member which is a viscoelastic member, but the spring member and the gel-like damper member are separate members. , Since they are placed in different places, the process of attaching the two members individually must be performed. Therefore, the work of connecting the movable body and the fixed body cannot be made efficient.

If the movable body and the fixed body are connected only by the spring member without using the gel-like damper member, excessive vibration of the movable body cannot be suppressed, and the movable body and the fixed body may collide with each other. Further, although the spring member is thin and easy to fix, once it is extended due to an impact or the like, it cannot return to its original shape. Therefore, there is a problem that it is easily broken by impact. Further, when responding to a design change such as a change in vibration characteristics, it is necessary to change the spring shape, but it cannot be said that it is easy.

On the other hand, when the movable body and the fixed body are connected only by the gel-like damper member without using the spring member, there is a limit even if the spring constant is increased, so that it is difficult to achieve the desired vibration characteristics. Further, if the spring constant is increased, the gel-like damper member becomes larger and heavier. Further, since the gel-like damper member is directly fixed to the movable body and the fixed body, it is difficult to select a usable adhesive when a poorly adhesive silicone gel is used as the gel-like damper member.

In view of the above problems, an object of the present invention is to propose a spring member that can utilize the characteristics of both a leaf spring and a viscoelastic body and can streamline the work of connecting a movable body and a fixed body.

In order to solve the above problems, the spring member according to the present invention includes a leaf spring and a viscoelastic body fixed to the leaf spring, and the leaf spring is first fixed to be fixed to a movable body. A portion, a second fixing portion fixed to the fixed body, and a spring portion connecting the first fixing portion and the second fixing portion are provided, and the viscoelastic body is arranged on the spring portion. It is characterized by that.

In the spring member of the present invention, a viscoelastic body is arranged in the spring portion of the leaf spring. Therefore, since the characteristics of both the leaf spring and the viscoelastic body can be utilized, it is easy to achieve the desired vibration characteristics. In addition, the viscoelastic body can prevent the leaf spring from being greatly deformed by an impact or the like and unable to return to its original shape. Therefore, the impact resistance is higher than when only the leaf spring is used. Further, since the leaf spring is thin, it is suitable for miniaturization and weight reduction as compared with the case where only a viscoelastic body is used. Further, since the fixing portion for the movable body and the fixed body is a leaf spring portion, it is easier to select an adhesive material than in the case of directly fixing a poorly adhesive viscoelastic body. Further, since it can be handled as one member, the work of connecting the movable body and the fixed body can be made more efficient.

In the present invention, the viscoelastic body is preferably arranged in a range including at least a part of a notch or a hole provided in the spring portion. In this way, the viscoelastic body can be arranged within the leaf thickness of the leaf spring, and the notch or the portion surrounding the hole can be connected in the in-plane direction of the leaf spring. Further, since the viscoelastic body is difficult to separate from the leaf spring and the viscoelastic body and the leaf spring can be deformed integrally, it is easy to utilize the characteristics of both the leaf spring and the viscoelastic body.

In the present invention, the viscoelastic body is thicker than the plate thickness of the spring portion and protrudes from the spring portion in at least one side in the plate thickness direction. For example, the viscoelastic body protrudes from the spring portion on both sides in the plate thickness direction (out-of-plane direction). In this way, the viscoelastic body can be made thicker than the leaf spring, so that the characteristics of the viscoelastic body can be easily utilized. In addition, the viscoelastic body is difficult to separate from the leaf spring, and the leaf spring can be protected by the viscoelastic body, so that the durability of the spring member can be improved.

Alternatively, in the present invention, the viscoelastic body may adopt a configuration in which the viscoelastic body is arranged within the plate thickness of the spring portion. In this way, a spring member having the characteristics of both a leaf spring and a viscoelastic body can be obtained while being thin.

In the present invention, the hole is a slit-shaped separation hole extending between the first fixing portion and the second fixing portion, and the separation hole is formed by the viscoelastic body arranged in the separation hole. It is preferable that the surrounding portions are connected in the in-plane direction of the leaf spring. By providing the leaf spring with a separation hole in this way, the leaf spring can be made elastic. Further, since the portion surrounding the separation hole can be connected in the in-plane direction by a viscoelastic body, it is possible to prevent the leaf spring from being deformed too much in the out-of-plane direction. Therefore, the impact resistance of the spring member can be improved. Further, the viscoelastic body arranged in the separation hole can increase the rigidity of the spring member in the in-plane direction.

In the present invention, the first fixing portion and the second fixing portion are annular, the second fixing portion is arranged on the outer peripheral side of the first fixing portion, and the spring portion is the first fixing portion and the said. An arm extending spirally between the second fixing portions is provided, and the hole is a slit-shaped separation hole provided between the adjacent arms, and is provided by the viscoelastic body arranged in the separation hole. It is preferable that the arms located on both sides of the separation hole are connected in the in-plane direction of the leaf spring. By providing the arm spirally extending from the inner peripheral side to the outer peripheral side in this way, the leaf spring can be elastically deformed in the out-of-plane direction. Therefore, the movable body fixed to the first fixed portion can be vibrated in the direction perpendicular to the leaf spring with respect to the fixed body fixed to the second fixed portion. Further, the viscoelastic body arranged in the separation hole can increase the rigidity of the spring member in the in-plane direction. Therefore, it is possible to prevent the movable body fixed to the first fixing portion from moving in the in-plane direction of the leaf spring.

In the present invention, it is preferable to provide a film fixed to the surface of the viscoelastic body. In this way, the spring member can be easily handled because the viscoelastic body can be prevented from coming into direct contact with the viscoelastic body. Further, the spring member can be easily fixed to another member via the film.

In the present invention, it is preferable to include an insert component in which a part is embedded in the viscoelastic body. In this way, the insert component can be fixed to the viscoelastic body without using an adhesive. Therefore, the insert component can be easily fixed, and the other component and the spring member can be fixed by using the insert component.

Next, the actuator according to the present invention is fixed to the spring member, the fixed body fixed to the second fixing portion of the spring member, and the first fixing portion of the spring member, and is fixed by the spring member. It is characterized by including a movable body connected to the fixed body and a magnetic drive mechanism for vibrating the movable body in the plate thickness direction of the spring member.

Next, the lens driving device according to the present invention includes the spring member, a fixed body fixed to the second fixing portion of the spring member, and a lens, and is attached to the first fixing portion of the spring member. It is characterized by including a movable body to be fixed and a lens driving mechanism for moving the movable body in the optical axis direction of the lens.

According to the present invention, since the viscoelastic body is arranged in the spring portion of the leaf spring, the characteristics of both the leaf spring and the viscoelastic body can be utilized. Therefore, it is easy to achieve the desired vibration characteristics. In addition, the viscoelastic body can prevent the leaf spring from being greatly deformed by an impact or the like and unable to return to its original shape. Therefore, the impact resistance is higher than when only the leaf spring is used. Further, since the leaf spring is thin, it is suitable for miniaturization and weight reduction as compared with the case where only a viscoelastic body is used. Further, since the fixing portion for the movable body and the fixed body is a leaf spring portion, it is easier to select an adhesive material than in the case of directly fixing a poorly adhesive viscoelastic body. Further, since it can be handled as one member, the work of connecting the movable body and the fixed body can be made more efficient.

It is a top view and a cross-sectional view of the spring member which concerns on Embodiment 1 of this invention. It is a top view of a leaf spring and a partially enlarged view thereof. It is explanatory drawing of the manufacturing method of the spring member of FIG. It is sectional drawing of the actuator provided with the spring member of FIG. It is sectional drawing of the lens drive device provided with the spring member of FIG. It is a top view of the spring member which concerns on Embodiment 2. FIG. It is sectional drawing of the spring member which concerns on Embodiments 3-5. It is sectional drawing of the spring member which concerns on Embodiment 6. It is sectional drawing of the spring member which concerns on Embodiment 7.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the plate thickness direction of the leaf spring 8 in the spring member 10 is LA, one side of the plate thickness direction LA is LA1, and the other side of the plate thickness direction LA is LA2. Further, the axis L is the central axis direction of the movable body 3 in the actuator 1, and one side in the direction in which the axis L extends (axis L direction) is L1 and the other side in the axis L direction is L2. When the movable body 3 and the fixed body 2 are connected by the spring member 10, the leaf thickness direction LA of the leaf spring 8 and the axis L coincide with each other.

[Embodiment 1]
(overall structure)
1 (a) is a plan view of the spring member 10 according to the first embodiment of the present invention, and FIG. 1 (b) is a cross-sectional view of the spring member 10 according to the first embodiment of the present invention (FIG. 1 (a). ) AA cross-sectional view). FIG. 2 is a plan view of the leaf spring 8 and a partially enlarged view thereof. As shown in FIG. 1, the spring member 10 includes a circular leaf spring 8 and a viscoelastic body 9 fixed to the leaf spring 8. In this embodiment, the leaf spring 8 is made of metal. A leaf spring 8 made of a material other than metal may be used. For example, the leaf spring 8 may be made of resin. The viscoelastic body 9 is arranged in the central portion of the leaf spring 8. The viscoelastic body 9 is thicker than the plate thickness of the leaf spring 8 and projects from the leaf spring 8 to both sides in the plate thickness direction LA. In this embodiment, the viscoelastic body 9 is a gel-like damper member. For example, as the viscoelastic body 9, a silicone gel having a needle insertion degree of 90 degrees to 110 degrees can be used.

As shown in FIGS. 1 and 2, the leaf spring 8 includes an annular first fixing portion 81, an annular second fixing portion 82 arranged on the outer periphery of the first fixing portion 81, and a first fixing portion 81. A spring portion 80 for connecting the second fixing portion 82 is provided. The spring portion 80 elastically deforms in the leaf thickness direction LA of the leaf spring 8. The spring portion 80 includes a plurality of arms 83 extending in the circumferential direction. Each arm 83 has an inner connecting portion 84 connected to the first fixing portion 81, an outer connecting portion 85 connected to the second fixing portion 82, and a circumferential direction from the inner connecting portion 84 toward the outer connecting portion 85. A spiral portion 86 extending to one side CCW is provided.

The spring portion 80 includes a slit-shaped separation hole 89 extending between the first fixing portion 81 and the second fixing portion 82. The separation holes 89 are provided one by one between the adjacent arms 83, and extend spirally along the shape of the arms 83 described later. The leaf spring 8 is provided with a plurality of separation holes 89 at equal intervals in the circumferential direction. In this embodiment, three separation holes 89 are provided. Each separation hole 89 extends from the inner connection portion 84 of each arm 83 to the outer connection portion 85.

The viscoelastic body 9 is arranged in the spring portion 80 of the leaf spring 8. As shown in FIG. 1A, in the present embodiment, the viscoelastic body 9 has a circular shape slightly larger than the spring portion 80 when viewed from the plate thickness direction LA, and the outer peripheral portion of the viscoelastic body 9 is the second. It covers the inner peripheral portion of the fixed portion 82. Further, the inner peripheral portion of the viscoelastic body 9 covers the entire first fixed portion 81. The viscoelastic body 9 is a member thicker than the plate thickness of the leaf spring 8, and projects from the leaf spring 8 toward at least one side in the plate thickness direction LA.

As shown in FIG. 1B, in the present embodiment, the viscoelastic body 9 is arranged in the filling portion 90 arranged in the separation hole 89 of the leaf spring 8 and LA1 on one side of the leaf spring 8 in the plate thickness direction LA. A first protruding portion 91 to be formed and a second protruding portion 92 arranged on the other side LA2 of the leaf spring 8 in the plate thickness direction LA are provided. The height (thickness) of the first protruding portion 91 and the second protruding portion 92 in the plate thickness direction LA is the same, but may be different.

(Detailed shape of the arm)
As shown in FIG. 2, the leaf spring 8 includes a first arm 83A, a second arm 83B arranged on one side CCW in the circumferential direction with respect to the first arm 83A, and a second arm as a plurality of arms 83. It is provided with three third arms 83C arranged on one side CCW in the circumferential direction with respect to 83B. Each of the three arms 83 includes an inner connecting portion 84, an outer connecting portion 85, and a spiral portion 86, as described above. The inner connecting portion 84 projects from the first fixing portion 81 toward the outer peripheral side, and is connected to the spiral portion 86 in a bent shape. Further, the outer connecting portion 85 projects from the second fixing portion 82 toward the inner peripheral side, and is connected to the spiral portion 86 in a bent shape.

The spiral portion 86 of each arm 83 extends in the circumferential direction over an angle range larger than the angle range (360 °) for one circumference. Therefore, when viewed from the radial direction, the four spiral portions 86 overlap each other at any angle position, and the four spiral portions 86 are arranged in all directions intersecting the plate thickness direction LA. Therefore, the leaf spring 8 has high rigidity in the direction orthogonal to the leaf thickness direction LA.

The spiral portion 86 of each arm 83 includes a plurality of bent portions 87 separated in the circumferential direction. In the present embodiment, the spiral portion 86 of each arm 83 has a first bent portion 87A closest to the inner connecting portion 84 in the circumferential direction and a CCW on one side in the circumferential direction of the first bent portion 87A as a plurality of bent portions 87. A second bent portion 87B located at 1 and a third bent portion 87C located at one CCW in the circumferential direction of the second bent portion 87B are provided.

The bent portion 87 includes an inclined portion 871 inclined with respect to the circumferential direction, a first bent portion 872 bent from one end (end portion on the outer peripheral side) of the inclined portion 871 to one CCW in the circumferential direction, and an inclined portion 871. A second bent portion 873 bent from the other end (the end on the inner peripheral side) to the other side CW in the circumferential direction is provided. Since the bent portion 87 has a shape that is bent in a plane orthogonal to the plate thickness direction LA in this way, the rigidity in the direction orthogonal to the plate thickness direction LA of each arm 83 is high by providing the bent portion 87. .. Therefore, the leaf spring 8 has high rigidity in the direction orthogonal to the leaf thickness direction LA.

In the leaf spring 8, three arms 83 are arranged at intervals of 120 ° in the circumferential direction, and each arm 83 has three bent portions 87 (first bent portion 87A, second bent portion 87B, third bent portion 87). Parts 87C) are arranged at intervals of 120 ° in the circumferential direction. Further, the inner connecting portion 84 and the first bent portion 87A are arranged at 120 ° intervals, and the third bent portion 87C and the outer connecting portion 85 are arranged at 120 ° intervals. The first bent portion 87A, the second bent portion 87B, and the third bent portion 87C have similar shapes, and the length of the inclined portion 871 is longer in the order of the first bent portion 87A, the second bent portion 87B, and the third bent portion 87C. It is increasing.

With such an arrangement, in the leaf spring 8, the first bent portion 87A, the second bent portion 87B, and the third bent portion 87C provided on the arms 83 different from each other are arranged in a row from the inner peripheral side to the outer peripheral side. .. Further, since the inner connecting portion 84 is arranged on the inner peripheral side of the first bent portion 87A and the outer connecting portion 85 is arranged on the outer peripheral side of the third bent portion 87C, the five bent portions are arranged from the inner peripheral side to the outer peripheral side. They are lined up in a row to the side. A configuration in which five bent portions are arranged in a row from the inner peripheral side to the outer peripheral side is provided at three locations at equal angular intervals in the leaf spring 8.

(Manufacturing method of spring member)
FIG. 3 is an explanatory view of a method of manufacturing the spring member 10 of FIG. The spring member 10 is manufactured by using a mold in which the first mold member 110 in which the circular recess 111 is formed, the second mold member 120 in which the circular recess 111 is formed, and the spacer 130 are assembled. First, the spacer 130 is arranged and assembled between the first mold member 110 and the second mold member 120, and at that time, the circular recess 111 of the first mold member 110 and the circular recess 121 of the second mold member 120 are assembled. A leaf spring 8 is arranged between them. On the surface of the leaf spring 8, a primer is applied in advance to the portions facing the circular recess 111 and the circular recess 121. Next, the space between the circular recesses 111 and 121 is filled with the gel material 140, the gel material 140 is cured together with the mold, and the viscoelastic body 9 is formed.

For example, when a thermosetting gel material 140 is used, the gel material 140 is heat-cured by placing the entire mold in a constant temperature bath and keeping the gel material 140 at a specified temperature for a specified time. When the gel material 140 is heat-cured, the portion in contact with the primer reacts with the primer and is fixed to the surface of the leaf spring 8 and the inner surface of the separation hole 89. Therefore, the cured viscoelastic body 9 is fixed to the leaf spring 8 by the adhesive force of the viscoelastic body 9 itself without using an adhesive.

Subsequently, after the mold is taken out from the constant temperature bath, the second mold member 120 and the spacer 130 are removed from the first mold member 110, and then the spring member 10 is removed from the first mold member 110 using a protrusion pin or the like. As a result, the filling portion 90 of the viscoelastic body 9 is arranged in the separation hole 89 of the leaf spring 8, and the first protruding portion 91, which is an inverted shape of the circular recess 111, and the circular recess 121 are formed on the surface of the leaf spring 8. The spring member 10 in which the second protruding portion 92 having an inverted shape is arranged is completed.

Instead of using a mold member having an inverted concave portion of the viscoelastic body 9, a spacer having the same thickness as that of the viscoelastic body 9 is arranged between the upper and lower mold members to form a mold. You may. In this way, it is easy to respond to changes in the thickness of the viscoelastic body 9.

(Actuator with spring member)
FIG. 4 is a cross-sectional view of the actuator 1 provided with the spring member 10 of FIG. The actuator 1 includes a fixed body 2 and a movable body 3, a spring member 10 that connects the fixed body 2 and the movable body 3, and a magnetic drive mechanism 6 that moves the movable body 3 relative to the fixed body 2 in the axis L direction. To be equipped. The magnetic drive mechanism 6 includes a magnet 61 arranged on the movable body 3 and a coil 62 arranged on the fixed body 2. It is also possible to reverse the arrangement of the magnet 61 and the coil 62.

The spring member 10 connects the movable body 3 and the fixed body 2 at two positions separated in the axis L direction, and supports the movable body 3 so as to be movable in the axis L direction. In the present embodiment, the spring member 10 includes a first spring member 10A arranged at the end of the movable body 3 on the L1 side and a second spring member 10B arranged at the end of the movable body 3 on the L2 side. In the first spring member 10A, the first fixing portion 81 is fixed to the end portion of the movable body 3 on the L1 side, and the second fixing portion 82 is fixed to the fixed body 2. Further, in the second spring member 10B, the first fixing portion 81 is fixed to the end portion of the movable body 3 on the L2 side, and the second fixing portion 82 is fixed to the fixed body 2.

(Fixed body)
The fixed body 2 includes a resin case 20 and a holder 4 held by the case 20. The case 20 includes a tubular case 21, a first lid member 22 fixed to the end of the tubular case 21 on the L1 side, and a second lid member 23 fixed to the end of the tubular case 21 on the L2 side. To be equipped with. The first lid member 22 includes an facing surface 221 that faces the end of the movable body 3 on the L1 side in the L direction of the axis. Further, the outer peripheral portion of the first lid member 22 projects toward the holder 4 side (L2 side). As shown in FIG. 4, the outer peripheral portion of the first spring member 10A is sandwiched between the outer peripheral portion of the first lid member 22 and the holder 4, and is fixed to the fixed body 2.

The second lid member 23 includes an facing surface 231 that faces the end of the movable body 3 on the L3 side in the L direction of the axis. At the end of the tubular case 21 on the L2 side, an annular projecting portion 29 projecting toward the inner peripheral side is provided. As shown in FIG. 4, the outer peripheral portion of the second spring member 10B is sandwiched between the annular protrusion 29 and the outer peripheral portion of the second lid member 23 and fixed to the fixed body 2.

The holder 4 includes an annular portion 42 arranged on the L2 side of the outer peripheral portion of the first lid member 22, and a coil fixing portion 43 projecting from the inner peripheral portion of the annular portion 42 toward the L2 side. The coil 62 is wound around the outer peripheral side of the coil fixing portion 43. The terminal pin 64 projects radially outward from the terminal holding portion 44 provided on the annular portion 42. A substrate 63 connected to the coil wire via a terminal pin 64 is fixed to the tubular case 21. The substrate 63 is arranged in a recess 24 provided on the outer peripheral surface of the tubular case 21.

(Movable body)
The movable body 3 includes a shaft 31 extending in the axial L direction at the center of the fixed body 2 in the radial direction, a magnet 61 fixed at substantially the center of the shaft 31 in the axial L direction, and a first yoke that overlaps the magnet 61 on the L1 side. 32, a second yoke 33 that overlaps the magnet 61 on the L2 side, a weight 30 that abuts on the first yoke 32 from the L1 side, a first receiving member 36 that abuts on the weight 30 from the L1 side, and a second yoke 33. A second receiving member 37 that comes into contact with the L2 side is provided. A first member 38 that fits from the L1 side to the end on the L1 side of the shaft 31 is attached to the end on the L1 side of the movable body 3, and L2 on the shaft 31 is attached to the end on the L2 side of the movable body 3. A second member 39 that fits from the L2 side is attached to the end on the side.

A first annular groove 361 that opens on the L1 side is provided between the first receiving member 36 and the outer peripheral surface of the shaft 31. The first member 38 includes a tubular portion 381 into which the end portion of the shaft 31 is fitted, and a disc portion 382 that extends from the end portion of the tubular portion 381 on the L1 side to the outer peripheral side, and the tubular portion 381 is the first receiver. It is fitted in the first annular groove 361 of the member 36. The disk portion 382 faces the facing surface 221 provided at the center of the first lid member 22 in the radial direction in the axis L direction. The first spring member 10A is sandwiched between the end portion of the first receiving member 36 on the L1 side and the inner peripheral portion of the disk portion 382 and fixed to the movable body 3.

Similarly, a second annular groove 371 that opens on the L2 side is provided between the second receiving member 37 and the outer peripheral surface of the shaft 31. The second member 39 includes a tubular portion 391 into which the end portion of the shaft 31 is fitted, and a disc portion 392 extending from the end portion of the tubular portion 391 on the L2 side to the outer peripheral side, and the tubular portion 391 is the second receiver. It is fitted in the second annular groove 371 of the member 37. The disk portion 392 faces the facing surface 231 provided at the center of the second lid member 23 in the radial direction in the axis L direction. The second spring member 10B is sandwiched between the end portion of the second receiving member 37 on the L2 side and the inner peripheral portion of the disk portion 392 and fixed to the movable body 3.

The magnet 61 has a cylindrical shape and is magnetized so as to be polarized into the north and south poles in the L direction of the axis. The shaft 31 extends in the axis L direction at the center of the fixed body 2 in the radial direction. On the outer peripheral side of the magnet 61, a coil fixing portion 43 provided on the holder 4 is arranged coaxially with the magnet 61. Therefore, the magnet 61 and the coil 62 are arranged coaxially.

The first yoke 32 is a magnetic plate whose outer diameter dimension is slightly larger than the outer diameter dimension of the magnet 61. The outer peripheral surface of the first yoke 32 projects radially outward from the outer peripheral surface of the magnet 61. The first yoke 32 is fixed to the surface of the magnet 61 on the L1 side by a method such as adhesion. The second yoke 33 is composed of two magnetic plates (first magnetic plate 34, second magnetic plate 35). The first magnetic plate 34 includes an end plate portion 341 arranged on the L2 side of the magnet 61, and a cylindrical side plate portion 342 extending from the outer edge of the end plate portion 341 to the L1 side. The side plate portion 342 is arranged on the outer peripheral side of the coil fixing portion 43. The second magnetic plate 35 has a disc shape slightly smaller than the end plate portion 341 of the first magnetic plate 34. The second magnetic plate 35 is laminated on the end plate portion 341 of the first magnetic plate 34 on the L2 side and welded to the end plate portion 341. In the second yoke 33, the second magnetic plate 35 is fixed to the surface of the magnet 61 on the L2 side by a method such as adhesion.

(Actuator operation)
When the actuator 1 energizes the coil 62, the magnetic drive mechanism 6 generates a driving force for driving the movable body 3 in the axis L direction. When the energization of the coil 62 is turned off, the movable body 3 returns to the origin position by the returning force of the spring member 10. Therefore, by intermittently energizing the coil 62, the movable body 3 vibrates in the axis L direction.

(Main effect of Embodiment 1)
As described above, the spring member 10 of the first embodiment has the leaf spring 8 and the viscoelastic body 9 fixed to the leaf spring 8, and the leaf spring 8 is the first fixed body connected to the movable body 3. A spring portion 80 is provided which connects the portion 81, the second fixing portion 82 connected to the fixed body 2, and the first fixing portion 81 and the second fixing portion 82, and the viscoelastic body 9 is arranged in the spring portion 80. Will be done.

Further, the actuator 1 provided with the spring member 10 of the first embodiment is fixed to the fixed body 2 fixed to the first fixing portion 81 of the spring member 10 and the second fixing portion 82 of the spring member 10, and is fixed to the spring member 10. A movable body 3 connected to the fixed body 2 and a magnetic drive mechanism for vibrating the movable body 3 in the plate thickness direction of the spring member 10 are provided.

In the spring member 10 of the first embodiment, the viscoelastic body 9 is arranged in the spring portion 80 of the leaf spring 8. Therefore, since the characteristics of both the leaf spring 8 and the viscoelastic body 9 can be utilized, it is easy to achieve the desired vibration characteristics. Further, the viscoelastic body 9 can suppress that the leaf spring 8 is greatly deformed due to an impact or the like and cannot return to the original shape. Therefore, the impact resistance is higher than when only the leaf spring 8 is used. Therefore, the durability of the actuator 1 can be improved. Further, since the leaf spring 8 is thin, it is suitable for miniaturization and weight reduction as compared with the case where only the viscoelastic body 9 is used. Further, since the fixing portions for the movable body 3 and the fixed body 2 are the first fixing portion 81 and the second fixing portion 82 provided on the leaf spring 8, the viscoelastic body 9 having poor adhesiveness is more than directly fixed. , It is easy to select the adhesive. Further, since it can be handled as one member, when the actuator 1 is used as a connecting body for connecting the movable body 3 and the fixed body 2, the step of connecting the movable body 3 and the fixed body 2 can be made more efficient.

In the first embodiment, the viscoelastic body 9 is arranged in a range including the separation hole 89 provided in the spring portion 80. Therefore, the viscoelastic body 9 is difficult to separate from the leaf spring 8, and the viscoelastic body 9 and the leaf spring 8 are integrally deformed, so that the characteristics of both the leaf spring 8 and the viscoelastic body 9 can be easily utilized.

In this embodiment, the spring portion 80 is provided with the separation hole 89, but the leaf spring 8 may be configured such that the spring portion 80 is provided with a notch. In this case, the same effect can be obtained by arranging the viscoelastic body 9 in the range including the notch.

In the first embodiment, the viscoelastic body 9 is thicker than the plate thickness of the spring portion 80, and protrudes from the spring portion 80 to both sides in the plate thickness direction LA (out-of-plane direction). In this way, the viscoelastic body 9 can be made thicker than the leaf spring 8, so that the characteristics of the viscoelastic body 9 can be easily utilized. Further, since the viscoelastic body 9 is difficult to separate from the leaf spring 8 and the leaf spring 8 can be protected by the viscoelastic body 9, the durability of the spring member 10 can be enhanced.

In the first embodiment, since the viscoelastic body 9 is arranged in the slit-shaped separation hole 89 extending between the first fixing portion 81 and the second fixing portion 82, the leaf spring 8 sandwiches the separation hole 89. The portions facing each other are connected in the in-plane direction of the leaf spring 8. When the leaf spring 8 is provided with the slit-shaped separation hole 89 in this way, the portion divided by the separation hole 89 becomes an elastically deformable arm 83. Therefore, the leaf spring 8 can be made elastic. Further, by arranging the viscoelastic body 9 in the separation hole 89, it is possible to prevent the leaf spring 8 from being deformed too much when it is deformed in the out-of-plane direction. Therefore, the impact resistance of the spring member 10 can be improved. Further, the viscoelastic body 9 arranged in the separation hole 89 can increase the rigidity of the spring member 10 in the in-plane direction.

In the first embodiment, the first fixing portion 81 and the second fixing portion 82 are annular, and the second fixing portion 82 is arranged on the outer peripheral side of the first fixing portion 81. The spring portion 80 includes an arm 83 extending spirally between the first fixing portion 81 and the second fixing portion 82, and also includes a slit-shaped separation hole 89 provided between adjacent arms 83. Then, the viscoelastic bodies 9 arranged in the separation holes 89 connect the arms 83 located on both sides of the separation holes 89 in the in-plane direction of the leaf spring 8. By providing the arm 83 spirally extending from the inner peripheral side to the outer peripheral side in this way, the leaf spring 8 can be elastically deformed in the out-of-plane direction. Therefore, the movable body 3 fixed to the first fixed portion 81 can be supported in a state in which it can vibrate in a direction perpendicular to the leaf spring 8 with respect to the fixed body 2 fixed to the second fixed portion 82. it can. Further, the viscoelastic body 9 arranged in the separation hole 89 can increase the rigidity of the spring member 10 in the in-plane direction. As a result, it is possible to prevent the movable body 3 fixed to the first fixing portion 81 from moving in the in-plane direction of the leaf spring 8. Therefore, when the actuator 1 vibrates the movable body 3, the movable body 3 vibrates. It is possible to suppress the movement in the direction intersecting the direction (axis L direction). Therefore, since the collision between the movable body 3 and the fixed body 2 can be suppressed, the impact resistance of the actuator 1 can be improved.

(Lens drive device with spring member)
FIG. 5 is a cross-sectional view of the lens driving device 1A provided with the spring member of FIG. The spring member 10 of the first embodiment can be used as a connecting body for connecting the movable body 3A and the fixed body 2A in the lens driving device 1A for moving an optical element such as a lens in the optical axis direction. As shown in FIG. 5, the lens driving device 1A has a fixed body 2A and a movable body 3A, a spring member 10 connecting the fixed body 2A and the movable body 3A, and an axis L of the movable body 3A with respect to the fixed body 2A. A magnetic drive mechanism 6 for relative movement in a direction is provided. The magnetic drive mechanism 6 is a lens drive mechanism, and includes a magnet 61 arranged on the movable body 3A and a coil 62 arranged on the fixed body 2A. It is also possible to reverse the arrangement of the magnet 61 and the coil 62.

The fixed body 2A includes a first case 25 and a second case 26, an image sensor 27 held in the second case 26, and a coil holder (not shown). The coil holder may be integrally formed with the first case 25 or the second case 26, or a separate member may be fixed to the first case 25 or the second case 26. The movable body 3A is an optical module including a lens 51 and a lens holder 52 that holds the lens 51. The magnet 61 is directly or indirectly fixed to the lens holder 52. Further, the end portion of the lens holder 52 on the L1 side projects toward the L1 side from the opening provided in the first case 25. The optical axis of the lens 51 coincides with the axis L of the movable body 3A, and the image sensor 27 is arranged on the optical axis (axis L) of the lens 51.

The spring member 10 connects the movable body 3A and the fixed body 2A at two positions separated in the axis L direction, and supports the movable body 3A so as to be movable in the axis L direction. In the present embodiment, the spring member 10 includes a first spring member 10A arranged at the end of the movable body 3A on the L1 side and a second spring member 10B arranged at the end of the movable body 3A on the L2 side. In the first spring member 10A, the first fixing portion 81 is fixed to the end portion of the movable body 3 on the L1 side, and the second fixing portion 82 is fixed to the fixed body 2. Further, in the second spring member 10B, the first fixing portion 81 is fixed to the end portion of the movable body 3 on the L2 side, and the second fixing portion 82 is fixed to the fixed body 2.

(Operation of lens drive device)
In the lens driving device 1A, when the coil 62 is energized, the magnetic driving mechanism 6 generates a driving force for driving the movable body 3A in the axis L direction. As a result, the position of the lens 51 on the optical axis (axis L) is adjusted. Therefore, the optical module provided with the lens 51 can be focused.

As described above, the spring member 10 can utilize the characteristics of both the leaf spring 8 and the viscoelastic body 9, and therefore has higher impact resistance than the case where only the leaf spring 8 is used. Therefore, the durability of the lens driving device 1A can be improved. Further, since the leaf spring 8 is thin, it is suitable for downsizing and weight reduction of the lens driving device 1A as compared with the case where only the viscoelastic body 9 is used. Further, since the fixing portions for the movable body 3 and the fixed body 2 are the first fixing portion 81 and the second fixing portion 82 provided on the leaf spring 8, the viscoelastic body 9 having poor adhesiveness is more than directly fixed. , It is easy to select the adhesive. Further, since it can be handled as one member, when it is used as a connecting body for connecting the movable body 3 and the fixed body 2 in the lens driving device 1A, the step of connecting the movable body 3 and the fixed body 2 can be made more efficient.

[Embodiment 2]
FIG. 6 is a plan view of the spring member 10C according to the second embodiment. The first embodiment has a configuration in which the viscoelastic body 9 is arranged in the entire spring portion 80 and the viscoelastic body 9 is arranged in the entire separation hole 89, but the range in which the viscoelastic body 9 is arranged is the same as that in the first embodiment. May be different. As shown in FIG. 6, the spring member 10C of the second embodiment includes viscoelastic bodies 9C partially arranged at a plurality of positions of the spring portion 80. By limiting the position and size of the viscoelastic body 9 in this way, the vibration characteristics of the leaf spring 8 can be utilized.

[Embodiment 3]
FIG. 7A is a cross-sectional view of the spring member 10D according to the third embodiment. In the first embodiment, the viscoelastic bodies 9 protrude on both sides of the leaf spring 8 in the plate thickness direction LA, but the viscoelastic bodies project only on either side of the leaf spring 8 in the plate thickness direction LA. It can also be configured to. The spring member 10D shown in FIG. 7A includes a leaf spring 8 and a viscoelastic body 9D, and the viscoelastic body 9D includes a filling portion 90 filled in a separation hole 89 of the leaf spring 8 and a leaf spring 8. It is provided with a second protruding portion 92 arranged on the other side LA2 of the leaf thickness direction LA, and is not provided with a portion of the leaf spring 8 arranged on one side LA1 of the plate thickness direction LA. In the third embodiment, the surface of one side LA1 of the spring member 10D in the plate thickness direction LA can be made flat. Further, the thickness of the spring member 10D in the plate thickness direction LA can be reduced.

[Embodiment 4]
FIG. 7B is a cross-sectional view of the spring member 10E according to the fourth embodiment. In the first embodiment, the thickness of the portion of the viscoelastic body 9 protruding from the leaf spring 8 in the plate thickness direction LA was constant, but the thickness of the viscoelastic body 9 does not have to be constant. The spring member 10E shown in FIG. 7B includes a leaf spring 8 and a viscoelastic body 9E, and the viscoelastic body 9E includes a filling portion 90 filled in a separation hole 89 of the leaf spring 8 and a leaf spring 8. A first protruding portion 91E arranged on one side LA1 of the leaf thickness direction LA and a second protruding portion 92E arranged on the other side LA2 of the leaf spring 8 in the plate thickness direction LA are provided. The 91E and the second protruding portion 92E are the thickest in the center and decrease in thickness toward the outer peripheral side. In this way, the central portion of the spring member 10E can be made less likely to be deformed than the outer peripheral portion.

[Embodiment 5]
FIG. 7C is a cross-sectional view of the spring member 10F according to the fifth embodiment. The spring member 10F shown in FIG. 7C includes a leaf spring 8 and a viscoelastic body 9F, and the viscoelastic body 9F includes a filling portion 90 filled in the separation hole 89 of the leaf spring 8. The viscoelastic body 9F is arranged within the plate thickness of the leaf spring 8. In this way, a spring member 10F having the characteristics of both the leaf spring 8 and the viscoelastic body 9F can be obtained while being thin. Further, both sides of the spring member 10F in the plate thickness direction LA can be made flat.

[Embodiment 6]
FIG. 8 is a cross-sectional view of the spring member 10G according to the sixth embodiment. The spring member 10F shown in FIG. 8 includes a leaf spring 8, a viscoelastic body 9G, and an insert component 11. The insert component 11 is, for example, a bolt, and in the example shown in FIG. 8, the head of the bolt is embedded in the viscoelastic body 9G. The threaded portion of the bolt is passed through a hole (not shown) of the leaf spring 8 and is exposed from the viscoelastic body 9G. The viscoelastic body 9G has a shape in which a portion of the bolt (insert component 11) in which the recess is embedded protrudes in the LA2 direction. By fixing the insert component 11 to the viscoelastic body 9G in addition to the leaf spring 8 in this way, the spring member 10G and other components can be easily connected.

The type of the insert component 11, the position where the insert component is embedded, and the shape of the viscoelastic body 9G are not limited to the example shown in FIG. 8, and can be changed as appropriate. For example, the insert component 11 may be a nut instead of a bolt.

[Embodiment 7]
FIG. 9 is a cross-sectional view of the spring member 10H according to the seventh embodiment. The spring member 10H shown in FIG. 9 includes a leaf spring 8, a viscoelastic body 9G, and a film 12. The film 12 is adhered to the surface of the viscoelastic body 9G. By covering the surface of the viscoelastic body 9G with the film 12 in this way, adhesion to other parts can be easily performed via the film 12. Further, by arranging the film 12 on the surface of the viscoelastic body 9G, the spring member 10H can be easily handled.

The film 12 may be adhered to the surface of the viscoelastic body 9G after molding the viscoelastic body 9G, or the film 12 coated with the primer may be arranged on the inner surface of the mold member and molded. When the surface to which the film 12 is attached is a flat surface, a large-sized film is set in a mold, integrally molded with the viscoelastic body together with the leaf spring 8, and then the viscoelastic body is punched together with the film. It is also possible to manufacture a spring member. Alternatively, the film can be easily separated at the time of mold release by making a half cut, a notch, a perforation, or the like in the film.

1 ... Actuator, 1A ... Lens drive device, 2, 2A ... Fixed body, 3, 3A ... Movable body, 4 ... Holder, 6 ... Magnetic drive mechanism, 8 ... Leaf spring, 9, 9C, 9D, 9E, 9E, 9F , 9G, 9H ... Viscoelastic body, 10, 10C, 10D, 10E, 10F, 10G, 10H ... Spring member, 10A ... 1st spring member, 10B ... 2nd spring member, 11 ... Insert part, 12 ... Film, 20 ... Case, 21 ... Cylindrical case, 22 ... 1st lid member, 23 ... 2nd lid member, 24 ... Recessed, 25 ... 1st case, 26 ... 2nd case, 27 ... Imaging element, 29 ... annular protrusion, 30 ... weight, 31 ... shaft, 32 ... first yoke, 33 ... second yoke, 34 ... first magnetic plate, 35 ... second magnetic plate, 36 ... first receiving member, 37 ... second receiving member, 38 ... 1st member, 39 ... 2nd member, 42 ... annular part, 43 ... coil fixing part, 44 ... terminal holding part, 51 ... lens, 52 ... lens holder, 61 ... magnet, 62 ... coil, 63 ... substrate, 64 ... Terminal pin, 80 ... Spring part, 81 ... First fixing part, 82 ... Fixed part, 83 ... Arm, 83A ... First arm, 83B ... Second arm, 83C ... Third arm, 84 ... Inner connection part, 85 ... Outer connection part, 86 ... spiral part, 87 ... bent part, 87A ... first bent part, 87B ... second bent part, 87C ... third bent part, 89 ... separation hole, 90 ... filled part, 91, 91E ... 1 protruding part, 92, 92E ... second protruding part, 110 ... first type member, 111 ... circular recess, 120 ... second type member, 121 ... circular recess, 130 ... spacer, 140 ... gel material, 221.231 ... Facing surface, 341 ... end plate part, 342 ... side plate part, 361 ... first annular groove, 371 ... second annular groove, 381 ... cylinder part, 382 ... disk part, 391 ... cylinder part, 392 ... disk part, 871 ... Inclined portion, 872 ... First bent portion, 873 ... First bent portion, CCW ... One side in the circumferential direction, CW ... One side in the circumferential direction, L ... Axial line, LA ... Plate thickness direction

Claims (11)

It has a leaf spring and a viscoelastic body fixed to the leaf spring.
The leaf spring includes a first fixing portion fixed to the movable body, a second fixing portion fixed to the fixed body, and a spring portion connecting the first fixing portion and the second fixing portion. ,
The viscoelastic body is a spring member characterized in that it is arranged in the spring portion. The spring member according to claim 1, wherein the viscoelastic body is arranged in a range including at least a part of a notch or a hole provided in the spring portion. The spring member according to claim 2, wherein the viscoelastic body is thicker than the plate thickness of the spring portion and protrudes from the spring portion in at least one side in the plate thickness direction of the leaf spring. The spring member according to claim 3, wherein the viscoelastic body protrudes from the spring portion to both sides in the plate thickness direction. The spring member according to claim 2, wherein the viscoelastic body is arranged within the plate thickness of the spring portion. The hole is a slit-shaped separation hole extending between the first fixing portion and the second fixing portion.
According to any one of claims 2 to 5, the viscoelastic body arranged in the separation hole connects the portions facing each other with the separation hole in the in-plane direction of the leaf spring. The spring member described. The first fixing portion and the second fixing portion are annular and have an annular shape.
The second fixing portion is arranged on the outer peripheral side of the first fixing portion.
The spring portion includes an arm that extends spirally between the first fixing portion and the second fixing portion.
The hole is a slit-shaped separation hole provided between the adjacent arms.
The spring member according to claim 6, wherein the arms located on both sides of the separation hole are connected in the in-plane direction of the leaf spring by the viscoelastic body arranged in the separation hole. The spring member according to any one of claims 2 to 7, further comprising a film fixed to the surface of the viscoelastic body. The spring member according to any one of claims 2 to 8, further comprising an insert component partially embedded in the viscoelastic body. The spring member according to any one of claims 1 to 9,
A fixed body fixed to the second fixing portion of the spring member,
A movable body fixed to the first fixing portion of the spring member and connected to the fixed body by the spring member.
An actuator including a magnetic drive mechanism that vibrates the movable body in the plate thickness direction of the spring member. The spring member according to any one of claims 1 to 9,
A fixed body fixed to the second fixing portion of the spring member,
A movable body provided with a lens and fixed to the first fixing portion of the spring member, and
A lens driving device including a lens driving mechanism for moving the movable body in the optical axis direction of the lens.

Images