JP2018136394A - Drive unit and optical device using drive unit - Google Patents

Abstract

[Problem] A pressure force for pressing a vibrator against a friction member generates a sliding resistance between the movable member and the guide member, and this sliding resistance reduces the moving speed of the movable member. [Solution] A vibration wave motor 150 including a vibrator 100, a fixed member 104 for holding the vibrator 100, a movable member 111 that moves relative to the vibrator 100, a pressure member 107 that presses the vibrator 100 against the movable member 111, and a first guide member 114 and a second guide member G that guide the movable member 111, in which the first guide member 114 engages with grooves 109g, 111g provided in both or either of the fixed member 104 and the movable member 111, and the second guide member G engages with a U-shaped groove 111b provided in the movable member 111 to guide the movable member 111. [Selected Figure] Figure 3

Description

  The present invention relates to a vibration wave motor, and more particularly, to a linear vibration wave motor having a plate-like elastic body, a drive device using the linear vibration wave motor, and an optical device that drives a lens in the optical axis direction using the drive device. .

  2. Description of the Related Art Conventionally, an ultrasonic motor characterized by a small size, light weight, high speed, and silent driving has been employed in an actuator such as a lens barrel of an imaging apparatus. This actuator is equipped with a linearly driven ultrasonic motor. For example, Patent Document 1 discloses a vibrator composed of a piezoelectric element and an elastic body, a movable member that holds a lens, a pressurizing member that pressurizes the vibrator against the movable member, and the movable member in the optical axis direction. An ultrasonic motor configured with a guide member that linearly guides the motor is disclosed. By generating a high frequency vibration in the vibrator and generating an elliptical motion at the tip of the protrusion formed on the vibrator, the vibrator moves relative to the movable member, thereby moving the lens in the relative movement direction. Can do.

JP-A-7-104166

  In the ultrasonic motor disclosed in Patent Document 1, the movable member is configured to be pressed against the guide member by the applied pressure. Due to this applied pressure, a sliding resistance is generated between the movable member and the guide member, and this sliding resistance is a load when the movable member moves in the relative movement direction. This sliding resistance has a problem that the moving speed of the movable member decreases.

  Therefore, an object of the present invention is to provide a drive device that reduces sliding resistance between a movable member and a guide member and prevents a decrease in moving speed.

  In order to achieve the above object, a driving device according to the present invention includes a vibrator, a fixed member that holds the vibrator, a movable member that moves relative to the vibrator, and a pressure that pressurizes the vibrator against the movable member. In a vibration wave motor including a member, a first guide member that guides the movable member, and a second guide member, the first guide member is provided on either or both of the fixed member and the movable member. The second guide member engages with the groove and engages with the groove provided in the movable member to guide the movable member.

  ADVANTAGE OF THE INVENTION According to this invention, the sliding device between a movable member and a guide member can be reduced, and the drive device which prevented the fall of the moving speed can be provided.

FIG. 3 is a perspective view illustrating configurations of a vibrator 100 and a holding member 103 according to an embodiment of the present invention. (A)-(D) It is a figure which shows the structure of the optical apparatus 10 which concerns on the 1st Example of this invention. It is a figure which shows the force which reaches to the member of the optical apparatus 10 which concerns on 1st Example of this invention. (A), (B) It is sectional drawing which shows the drive state of the optical apparatus 10 which concerns on the 1st Example of this invention. (A)-(D) It is a figure which shows the structure of the optical apparatus 20 which concerns on the 2nd Example of this invention. It is a figure which shows the force which reaches to the member of the optical apparatus 20 which concerns on the 2nd Example of this invention. (A), (B) It is sectional drawing which shows the drive state of the optical apparatus 20 which concerns on the 2nd Example of this invention. (A)-(D) It is a figure which shows the structure of the optical apparatus 30 which concerns on the 3rd Example of this invention. It is a figure which shows the force which reaches to the member of the optical apparatus 30 which concerns on the 3rd Example of this invention. (A), (B) It is sectional drawing which shows the drive state of the optical apparatus 30 which concerns on the 3rd Example of this invention. (A), (B) It is a figure which shows the structure of the optical apparatus 50 of a prior art example.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the drawings, the same reference numerals indicate the same members. In the present specification, a direction in which a vibrator 100 and a friction member 112, which will be described later, move relative to each other, is an X direction, and a pressurizing direction in which the vibrator 100 is pressed against the friction member 112 is a Z direction. In the Z direction, the direction from the vibrator 100 to the friction member 112 is defined as + Z direction, and the direction from the friction member 112 to the vibrator 100 is defined as −Z direction. Further, an orthogonal direction orthogonal to the X direction and the Z direction is defined as a Y direction.

  FIG. 1 is a perspective view showing configurations of the vibrator 100 and the holding member 103 according to the embodiment of the present invention. The vibrator 100 includes a vibration plate 101 and a piezoelectric element 102, and the piezoelectric element 102 that vibrates at a high frequency (vibrates at a frequency in the ultrasonic region) is fixed to the vibration plate 101. The vibration plate 101 has a rectangular flat plate portion 101d and a protrusion 101a on the flat plate portion 101d. By applying a high-frequency voltage to the piezoelectric element 102, the vibrator 100 is set to vibrate at a high frequency and resonate in the natural vibration mode in the X direction which is the longitudinal direction and the Y direction which is the short direction. This resonance causes an elliptical motion at the tip of the protrusion 101a.

  The vibrator 100 is pressurized against a friction member 112 fixed to a lens holding member 111 described later. When the above-described elliptical motion is generated in this pressurized state, the vibrator 100 is driven via a frictional force. You can gain power. With this driving force, the vibrator 100 can move relative to the friction member 112 by high-frequency vibration.

  At both ends in the relative movement direction of the rectangular flat plate portion 101d of the vibration plate 101, holding portions 101b for holding the vibrator 100 on the holding member 103 are provided, and the holding portion 101b has a holding hole 101c. Is provided. Each holding member 103 includes a holding protrusion 103a at a position corresponding to the holding hole 101c of the holding portion 101b. The holding protrusion 103a of the holding member 103 engages with the holding hole 101c, and the engaging portion is fixed by means such as adhesion. With this configuration, the vibrator 100 and the holding member 103 can move together without any play in the relative movement direction.

2A and 2B are perspective views of the optical device 10 viewed from different angles, FIG. 2C is a front view, and FIG. 2D is a cross-sectional line IID-IID in FIG. FIG. The protrusion 101 a of the vibrator 100 is in contact with the friction member 112. The pressurizing member 107 is a spring member such as a compression spring for pressurizing the vibrator 100 against the friction member 112. One end of the pressurizing member 107 is in contact with the fixing member 104 and the other end is in contact with the pressurizing plate 106. The pressurizing member 107 is a vibrator through a plate-like pressurizing plate 106 for uniformizing the pressurizing force F ₁ of the pressurizing member 107 and a buffer member 105 such as a felt that suppresses vibration damping of the vibrator 100. 100 is pressed against the friction member 112.

  The fixing member 104 is fixed to a lens barrel (not shown) and holds the vibrator 100. As shown in FIG. 2C, two rollers 108 are provided between the inner wall 104a of the fixing member 104 and the outer surface of the holding member 103 in the X direction. When these rollers 108 roll, the fixed member 104 and the holding member 103 are not restricted in relative movement in the pressing direction (Z direction), but are restricted in relative movement in the relative movement direction (X direction). It becomes the composition like this. Since the relative movement of the fixing member 104 and the holding member 103 in the Z direction is not restricted, errors caused by component tolerances, assembly tolerances, and the like are absorbed, and the protrusions 101a of the vibrator 100 are stably brought into contact with the friction member 112. be able to. Further, the relative movement in the X direction of the fixing member 104 and the holding member 103 is restricted, so that there is no backlash in the relative movement direction in the X direction.

  The friction member 112 is fixed to the lens holding member 111 with a screw 115 and integrated with the lens holding member 111. The friction member 112 can move relative to the fixing member 104, the holding member 103, and the vibrator 100 by the driving force obtained by the high-frequency vibration of the vibrator 100. That is, the lens holding member 111 moves relative to the vibrator 100 in the X direction that is the relative movement direction together with the friction member 112.

  The lens holding member 111 is a member for holding the lens L, and corresponds to a movable member of the present invention. The lens holding member 111 is guided in the relative movement direction by a rolling member, which will be described later, and a guide bar G. The rolling member engages with, for example, a rolling groove portion 109 g provided on the support plate 109 fixed to the fixing member 104 and a rolling groove portion 111 g provided on the lens holding member 111. Further, the guide bar G is engaged with a U groove portion 111 b provided in the lens holding member 111, whereby the lens holding member 111 is guided. The rolling member corresponds to the first guide member of the present invention, and the guide bar G corresponds to the second guide member of the present invention.

  2C and 2D, a portion surrounded by a broken line is a vibration wave motor 150 (ultrasonic motor). The vibration wave motor 150 includes a vibrator 100, a fixing member 104, a holding member 103, a pressure member 107, and the like, and relatively moves the friction member 112 by a driving force obtained by high-frequency vibration of the vibrator 100.

  In FIG. 2D, a portion surrounded by an alternate long and short dash line is the driving device 160. The driving device 160 includes a vibration wave motor 150 and can relatively move the lens holding member 111 in the X direction, which is a relative movement direction, by high-frequency vibration of the vibrator 100.

  The optical device 10 includes a lens L, a guide bar G, and a driving device 160. Since the lens L is fixed to the lens holding member 111, the lens L is moved by relative movement between the vibrator 100 and the friction member 112. Can be moved in the X direction which is the optical axis direction.

  In the vibration wave motor 150 according to the embodiment of the present invention, the first guide member is engaged with the groove provided in either or both of the fixed member 104 and the movable member, and the second guide member is provided on the movable member. The movable member is guided by engaging with the groove portion. With this configuration, the moving speed of the lens holding member 111 is prevented from decreasing due to the sliding resistance when the lens holding member 111 moves in the optical axis direction. Hereinafter, the present invention will be described with reference to more specific examples.

(First embodiment)
The configuration of the optical device 10 according to the first embodiment of the present invention will be described with reference to FIGS. The lens holding member 111 has a substantially annular holding portion that holds the lens L, an extension portion 111a that is provided in the substantially annular holding portion and extends in the relative movement direction, and is spaced apart from the extension portion 111a and is substantially annularly held. And a U-groove portion 111b provided in the portion. In the extending portion 111a, two rolling groove portions 111g are provided on the surface on the + Z direction side along the relative movement direction. The U groove 111b is engaged with a guide bar G fixed to a lens barrel (not shown).

  The support plate 109 includes two rolling groove portions 109g on the surface on the −Z direction side along the relative movement direction, and is fixed to the fixing member 104 by screws 115. At the time of fixing, two rolling balls 114 that are rolling members are incorporated side by side in the X direction between the lens holding member 111 and the support plate 109. These two rolling balls 114 engage with both the rolling groove 109g of the support plate 109 and the rolling groove 111g of the lens holding member 111, and when the lens holding member 111 moves in the relative movement direction. The rolling ball 114 rolls between the rolling groove 109g and the rolling groove 111g.

  As described above, in the first embodiment, the rolling member is the spherical rolling ball 114, and the rolling member is engaged with the groove provided in both the movable member and the fixed member 104. is there. Further, the rolling ball 114 is engaged with the rolling groove 111g of the lens holding member 111, and the guide bar G is engaged with the U groove 111b of the lens holding member 111, whereby the lens holding member 111 is in the optical axis direction. Guided straight in the X direction. That is, the lens holding member 111 is guided in a straight line by the rolling ball 114 and the guide bar G.

  The spherically-shaped rolling ball 114 is engaged with the rolling groove portion 111g provided on the lens holding member 111 and the rolling groove portion 109g provided on the support plate 109, so that the lens holding member 111 moves in the relative movement direction. Sliding resistance during movement is reduced. The lens holding member 111, the guide bar G, the rolling ball 114, the rolling groove portion 109g, and the rolling groove portion 111g correspond to the movable member, the second guide member, the first guide member, and the groove portion in the present invention, respectively. In addition, since the support plate 109 is fixed to the fixing member 104 by screws 115, the support plate 109 corresponds to the fixing member of the present invention together with the fixing member 104.

Next, referring to FIG. 3, the pressing force F _{1 applied} to the lens holding member 111, the urging force F _12b for urging the lens holding member 111 against the rolling ball 114, and the lens holding member 111 with the guide bar G The energizing force _F13b that energizes against will be described. The lens holding member 111 is given a pressure F ₁ by the pressure member 107 via the friction member 112. The pressure F _1, the lens holding member 111 is urged against Utatedodama 114 and the guide bar G. That is, by the pressing force _{F 1,} the rolling groove 111g pressure reaction force _{F 12} is generated at the point A, pressure reaction force _{F 13} is generated at the point B in the U groove 111b. And considering the balance equation of force in the pressure direction (Z direction in the figure)
F ₁ = F ₁₂ + F ₁₃ (1)
It is.

Here, a point where the extension line D in the direction in which the pressing force F ₁ acts and a straight line connecting the two action points A and B are defined as an intersection point C. A force F _{12v having} a component perpendicular to the straight line connecting the two reaction points A and B with the pressure reaction force F ₁₂ and the pressure reaction force F ₁₃ , a force F _{12h having} a component parallel to F _13v , Decomposes into F _13h .

Further, an urging force F _{12 b} that urges the lens holding member 111 against the rolling ball 114 is generated by the pressing force F ₁ of the pressing member 107. Further, the biasing force _{F 13b} for urging the lens holding member 111 by pressing force F1 of the pressing member 107 to the guide bar G occurs. Biasing force F _12b is a force equal opposite magnitude direction to the pressing reaction force F _12. Further, the urging force F _13b is a force having the opposite direction and the same magnitude as the force F _13v of the vertical component of the pressure reaction force F ₁₃ .

Here, considering the position where the urging force F _12b and the urging force F _13b act, when viewed from the relative movement direction, the extension point D in the direction in which the application point A of the _urging force F _12b and the applied pressure F ₁ act. the distance _{L 12} between shorter than the distance _{L 13} between the point B and the extended line D of the biasing force _{F 13b.} That is, distance L ₁₂ <distance L ₁₃ . Using this, the relationship between the distance L ₂ from the point of action A of the pressure reaction force F ₁₂ to the intersection C and the distance L ₃ from the point of action B of the pressure reaction force F _{13 to} the point of intersection C is:
L ₁₂ : L ₁₃ = L ₂ : L ₃
L ₂ <L ₃ (2)
It becomes. Here, considering the balance of moments around intersection C,
F _12v × L ₂ = F _13v × L ₃ (3)
It is. Equation (2), the force of the vertical direction component of (3) pressure reaction force _{F 12 F 12v,} magnitude of the force _{F 13v} in the vertical direction component of the pressure reaction force _{F 13} is
F _2v > F _3v (4)
It becomes. Biasing force _{F 12b} are equal in magnitude to the pressure reaction force _{F 12,} with a equal to the magnitude of the force _{F 13v} in the vertical direction component, and the urging force _{F 12b} of the urging force _{F 13b} is pressure reaction force _{F 13} Considering the magnitude relationship of power F _13b , from equations (3) and (4),
F _12b > F _13b (5)
It becomes. That is, the distance L ₂ than the distance L ₃ is configured to be shorter, be less than urging force F _12b is biased to force F _13b with being biased to the guide bar G on the rolling ball 114 it can. This effect will be described later. The urging force F _12b and the urging force F _13b correspond to the first urging force and the second urging force of the present invention, respectively.

  FIG. 11A is a perspective view showing a configuration of a conventional optical device 50, and FIG. 11B is a side view thereof. The lens holding member 1 to which the lens L is fixed is linearly guided in the optical axis direction (X direction) by two guide bars G1 and G2.

  A pressure F is generated by the pressure member 7, and the guide bar G1 is provided on the extension line D in the direction in which the pressure F acts. Therefore, the lens holding member 1 is urged against the guide bar G1 by the pressure F. Has been. With this configuration, when the lens holding member 1 moves in the optical axis direction, the lens holding member 1 moves while sliding with respect to the guide bar G1, and a sliding resistance corresponding to the magnitude of the pressure F is generated. To do. For this reason, in the optical device 50 of the conventional example, when the lens holding member 1 moves in the optical axis direction, the moving speed is lowered due to the sliding resistance.

In contrast to the above-described conventional example, in the first embodiment of the present invention, the applied pressure F ₁ is received by the rolling ball 114 and the guide bar G. Further, the urging force F _{13 b} urged by the guide bar G is smaller than the urging force F _{12 b} urged by the rolling ball 114. For this reason, when the lens holding member 111 moves, the sliding resistance generated between the lens holding member 111 and the guide bar G is small. Further, when the lens holding member 111 moves, the rolling ball 114 rolls, so that sliding resistance hardly occurs. Therefore, in the first embodiment of the present invention, the sliding resistance generated between the U groove 111b of the lens holding member 111 and the guide bar G when the lens holding member 111 moves in the relative movement direction is reduced. be able to.

  4A and 4B are cross-sectional views showing a driving state of the optical device 10 according to the first embodiment of the present invention taken along a cross-sectional line IV-IV in FIG. 4A shows a state where the lens holding member 111 is at the center position of the driving range, and FIG. 4B shows a state where the lens holding member 111 is at the end of the driving range.

In the optical device 10 according to the first embodiment of the present invention, two rolling balls 114 are provided in the relative movement direction, and rolling is performed as the lens holding member 111 moves from the center to the end. It moves while rolling between the groove 109g and the rolling groove 111g. Along with this movement, the relative positional relationship between the rolling ball 114 and the pressure member 107 also changes. Then, in the entire moving range in which the lens holding member 111 moves from the center to the end, the pressing force F ₁ applied by the pressing member 107 on the projection plane in the direction perpendicular to the relative movement direction and the pressing force F ₁ direction. Acts in the direction passing between the two rolling balls 114. Since the receiving pressure F ₁ between the two rolling balls 114, Utatedodama 114 in moving the whole range it is to maintain a state engaged with the rolling groove 109g and the rolling groove 111g Can do. For this reason, the lens holding member 111 is guided in a straight line stably while maintaining a certain distance without floating on the support plate 109.

Above As described, in the optical device 10 according to a first embodiment of the present invention, the rolling ball from the position of the guide bar G with respect to the direction of extension D which acts pressure F ₁ applied by the pressing member 107 The configuration is such that the position 114 is closer. With such a configuration, the urging force F _12b that urges the lens holding member 111 is smaller than the urging force F _13b that urges the guide bar G. As a result, it is possible to obtain a remarkable effect of reducing the sliding resistance between the movable member and the guide member, preventing the movement speed from being lowered, and improving the responsiveness.

(Second embodiment)
Next, the configuration of the optical device 20 according to the second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the rolling member is a spherical rolling ball 114, and the rolling member is engaged with the groove portions provided on the movable member side and the fixed member 104 side. The second embodiment is different from the first embodiment in that the rolling member is a bearing 214 and the bearing 214 pivotally fixed to the fixed member 204 is engaged with a groove provided in the movable member. Is a point. The description of the same parts as in the first embodiment will be omitted, and only the parts different from the first embodiment will be described.

  FIGS. 5A to 5D showing the configuration of the optical device 20 of the second example correspond to FIGS. 2A to 2D of the first example, respectively. The bearing 214 has a curved surface 214a having a curvature in the outer diameter on the projection surface in the relative movement direction, that is, the YZ plane, and a hole in the center of the bearing 214. A fixed shaft 216 is inserted into the hole. The bearing 214 is shown in a simplified shape.

  In the extending portion 211a extending in the relative movement direction of the lens holding member 211, a rolling groove portion 211g is provided on the surface on the + Z direction side along the relative movement direction. The U groove 211b is engaged with a guide bar G fixed to a lens barrel (not shown).

  The fixing member 204 includes a fixing hole 204c, and a fixing shaft 216 is fixed to the fixing hole 204c. By fixing the fixed shaft 216 in the fixing hole 204 c, the bearing 214 is pivotally fixed with respect to the fixing member 204. The curved surface portion 214a having the outer diameter of the bearing 214 is engaged with the rolling groove portion 211g, and when the lens holding member 211 moves in the relative movement direction, the bearing 214 rotates about the fixed shaft 216 while rotating. Roll 211g.

  Thus, in the second embodiment, the rolling member is the bearing 214 having the curved surface portion 214a, and the rolling member is engaged with the groove portion provided in the movable member. Further, the bearing 214 having the curved surface portion 214a is engaged with the rolling groove portion 211g of the lens holding member 211, and the guide bar G is engaged with the U groove portion 211b of the lens holding member 211, so that the lens holding member 211 has the optical axis. The vehicle is guided straight in the X direction. That is, the lens holding member 211 is guided in a straight line by the bearing 214 and the guide bar G.

  The bearing 214 having the curved surface portion 214a pivotally fixed to the fixing member 204 is engaged with the rolling groove portion 211g provided in the lens holding member 211, so that the lens holding member 211 is moved in the relative movement direction. Sliding resistance is reduced. The lens holding member 211, the bearing 214, and the rolling groove 211g correspond to the movable member, the first guide member, and the groove in the present invention, respectively. Further, the support plate 109 required in the first embodiment is not necessary in the second embodiment, and the fixing member 204 corresponds to the fixing member of the present invention.

Next, referring to FIG. 6, the pressing force F _{2 applied} to the lens holding member 211, the urging force F _{22 b that} urges the lens holding member 211 against the bearing 214, and the lens holding member 211 against the guide bar G. The energizing force F _23b that energizes will be described. FIG. 6 corresponds to FIG. The lens holding member 211 is given a pressing force F ₂ by the pressure member 207 via the friction member 212. The pressure F _2, the lens holding member 211 is urged against the bearing 214 and the guide bar G. That is, by the pressing force _{F 2,} pressure reaction force _{F 22} is generated at the point A on the bearing 214, pressure reaction force _{F 23} is generated at the point B in the U groove 211b. When the balance of forces in the pressurizing direction (Z direction in the figure) is considered in the same manner as in the first embodiment, the same effect as in the first embodiment can be obtained.

That is, in the second embodiment of the present invention, the pressing force F ₂ is received by the bearing 214 and the guide bar G, and the biasing force F _{23 b} biased by the guide bar G is biased by the bearing 214. The biasing force F _22b is smaller. Considering the position where the _urging force F _22b and the urging force F _23b are applied, the point of action A of the _urging force F _22b and the extension line D in the direction in which the applied force F ₂ acts when viewed from the relative movement direction. distance _{L 22} is shorter than the distance _{L 23} between the point B and the extended line D of the biasing force _{F 23b.} That is, distance L ₂₂ <distance L ₂₃ . The _urging force F _22b and the urging force F _23b correspond to the first urging force and the second urging force of the present invention, respectively.

  For this reason, when the lens holding member 211 moves, the sliding resistance generated between the lens holding member 211 and the guide bar G is small. Further, when the lens holding member 211 moves, the bearing 214 rolls, so that almost no sliding resistance occurs. For this reason, in the second embodiment of the present invention, the sliding resistance generated between the U groove 211b of the lens holding member 211 and the guide bar G when the lens holding member 211 moves in the relative movement direction is reduced. be able to.

  FIGS. 7A and 7B are cross-sectional views showing a driving state of the optical device 20 according to the second embodiment taken along a cross-sectional line VII-VII in FIG. FIG. 7A shows a state in which the lens holding member 211 is at the center of the moving range, and FIG. 7B shows a state in which the lens holding member 211 is at the end of the driving range. 4 (A) and FIG. 4 (B) respectively.

In the optical device 20 according to the second embodiment of the present invention, since one bearing 214 is provided in the relative movement direction and is fixed to the fixing member 204, the lens holding member 211 is moved in the relative movement direction. However, the relative positional relationship between the bearing 214 and the pressure member 207 does not change. Then, in the entire moving range in which the lens holding member 211 moves from the center to the end, the pressure F applied by the pressure member 207 on the projection plane in the orthogonal direction orthogonal to the direction of the relative movement direction and the pressure F _{2. A} bearing 214 is provided on the _two extension lines. Since the receiving pressure F ₂ by a bearing 214, a bearing 214 in the moving range throughout it can be kept engaged with the rolling groove 211 g.

Above As described, the second in the optical device 20 according to the embodiment of the bearing 214 than the position of the guide bar G with respect to the direction of extension D which acts pressure F ₂ provided by the pressure member 207 of the present invention It is configured so that the position is closer. With such a configuration, the urging force F _22b that urges the lens holding member 211 is smaller than the urging force F _23b that urges the guide bar G. As a result, it is possible to obtain a remarkable effect of reducing the sliding resistance between the movable member and the guide member, preventing the movement speed from being lowered, and improving the response speed.

Furthermore, since in the second embodiment, regardless of the relative direction of movement the position of the lens holding member 211, always bearing 214 is subjected to pressure F _2, bearing 214 is sufficient at least one optical There is an advantage that the size of the device 20 in the relative movement direction can be reduced.

(Third embodiment)
Next, the configuration of the optical device 30 according to the third embodiment of the present invention will be described with reference to FIGS. In the second embodiment, the rolling member is a bearing 214, and the bearing 214 pivotally fixed on the fixed member 204 side is engaged with a groove provided on the movable member side. The third embodiment is different from the second embodiment in that the bearing 314 pivotally fixed to the movable member is engaged with a groove provided in the fixed member 304. The description of the same parts as in the first embodiment is omitted, and only the parts different from the first embodiment will be described.

  FIGS. 8A to 8D showing the configuration of the optical device 30 of the third embodiment correspond to FIGS. 2A to 2D of the first embodiment, respectively. The bearing 314 has a curved surface portion 314a having a curvature in the outer diameter on the projection surface in the relative movement direction, that is, the YZ plane, and has a hole in the center of the bearing 314. A fixed shaft 316 is inserted into the hole. The bearing 314 is illustrated in a simplified shape.

  Two fixed holes 311c are provided in the Y direction along the relative movement direction in the extending portion 311a extending in the relative movement direction of the lens holding member 311. The bearing 314 is pivotally fixed to the lens holding member 311 by fixing the fixed shaft 316 to the fixing hole 311c. The U groove 311b is engaged with a guide bar G fixed to a lens barrel (not shown).

  The support plate 309 includes two rolling groove portions 309g on the surface on the −Z direction side along the relative movement direction, and is fixed to the fixing member 304 by screws 315. At the time of fixing, two bearings 314 that are two rolling members are engaged with the two rolling groove portions 309g of the support plate 309 side by side in the X direction. When the lens holding member 311 moves in the relative movement direction, the bearing 314 rolls around the rolling groove 309g while rotating around the fixed shaft 316.

  As described above, in the third embodiment, the rolling member is the bearing 314 having the curved surface portion 314 a, and the rolling member is engaged with the groove portion provided in the fixed member 304. Further, the bearing 314 having the curved surface portion 314a is engaged with the rolling groove portion 309g of the fixing member 304, and the guide bar G is engaged with the U groove portion 311b of the lens holding member 311, whereby the lens holding member 311 is in the optical axis direction. The vehicle is guided straight in the X direction. That is, the lens holding member 311 is guided in a straight line by the bearing 314 and the guide bar G.

  The bearing 314 having the curved surface portion 314a pivotally fixed to the movable member is engaged with the rolling groove portion 309g provided on the support plate 309, thereby sliding the lens holding member 311 when moving in the relative movement direction. Resistance is reduced. The lens holding member 311, the bearing 314, and the rolling groove portion 309g correspond to the movable member, the first guide member, and the groove portion in the present invention, respectively. Further, since the support plate 309 is fixed to the fixing member 304 by the screw 315, the support plate 309 corresponds to the fixing member in the present invention together with the fixing member 304.

Next, referring to FIG. 9, the pressing force F _{3 applied} to the lens holding member 311, the urging force F _{32 b that} urges the lens holding member 311 against the bearing 314, and the lens holding member 311 against the guide bar G. The biasing force F _33b that biases will be described. FIG. 9 corresponds to FIG. The lens holding member 311 is given a pressing force F ₃ by the pressure member 307 via the friction member 312. The lens holding member 311 is urged against the guide bar G and the support plate 309 by the pressure F ₃ . That is, by the pressing force _{F 3,} pressure reaction force _{F 32} is at the working point A on the rolling groove 309g of the support plate 309, pressure reaction force _{F 33} is produced, respectively, in the point B in the U groove 311b . When the balance of forces in the pressurizing direction (Z direction in the figure) is considered in the same manner as in the first embodiment, the same effect as in the first embodiment can be obtained.

That is, in the third embodiment of the present invention, the pressure F ₃ is received by the bearing 314 and the guide bar G, and the biasing force F _33b biased by the guide bar G is biased by the bearing 314. The biasing force F _32b is smaller. Further, when considering the position where the _urging force F _32b and the urging force F _33b act, the point of action A of the _urging force F _32b and the extension line D in the direction in which the applied force F ₃ acts when viewed from the relative movement direction. distance _{L 32} is shorter than the distance _{L 33} between the point B and the extended line D of the biasing force _{F 33b.} That is, distance L ₃₂ <distance L ₃₃ . The _urging force F _32b and the urging force F _33b correspond to the first urging force and the second urging force of the present invention, respectively.

  For this reason, when the lens holding member 311 moves, the sliding resistance generated between the lens holding member 311 and the guide bar G is small. Further, when the lens holding member 311 moves, the bearing 314 rolls, so that sliding resistance hardly occurs. Therefore, in the third embodiment of the present invention, the sliding resistance generated between the U groove 311b of the lens holding member 311 and the guide bar G when the lens holding member 311 moves in the relative movement direction is reduced. be able to.

  FIGS. 10A and 10B are cross-sectional views showing a driving state of the optical device 30 according to the third example taken along a cross-sectional line XX in FIG. 8D. FIG. 10A shows a state in which the lens holding member 311 is at the center of the moving range, and FIG. 10B shows a state in which the lens holding member 311 is at the end of the moving range. 4 (A) and FIG. 4 (B) respectively.

In the optical device 30 according to the third embodiment of the present invention, since two bearings 314 are provided in the relative movement direction and are fixed to the lens holding member 311, the lens holding member 311 is moved in the relative movement direction. And move in the relative movement direction. Then, in the entire moving range in which the lens holding member 311 moves from the center to the end, the pressure F applied by the pressure member 307 on the projection plane in the direction perpendicular to the relative movement direction and the direction of the pressure F ₃ is applied. ₃ acts in the direction passing between the two bearings 314. Since the receiving pressure F ₃ between the two bearings 314, a bearing 314 in the moving range throughout it can be kept engaged with the rolling groove 309 g. For this reason, the lens holding member 311 is guided straight and stably while maintaining a certain distance without floating with respect to the support plate 309.

As described above, in the optical device 30 according to the third embodiment, towards the position of the bearing 314 than the position of the guide bar G with respect to the direction of extension D which acts pressure F ₃ provided by the pressure member 307 Is configured to be close. With such a configuration, the biasing force F _32b that biases the lens holding member 311 is smaller than the biasing force F _33b that biases the guide bar G. As a result, it is possible to obtain a remarkable effect of reducing the sliding resistance between the movable member and the guide member, preventing the movement speed from being lowered, and improving the responsiveness.

  Furthermore, in the third embodiment, since two bearings 314 are provided in the relative movement direction, the lens holding member 311 is not easily rotated around the Z direction even when an impact or the like is applied to the optical device 30, and stable. There is an advantage that you can guide straight ahead.

  The preferred embodiments of the present invention have been described above, but the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the gist thereof.

  The present invention can be used for electronic devices that are required to be small and light and have a wide driving speed range, particularly optical devices and the like.

100 Vibrators 104, 204, 304 Fixing members 107, 207, 307 Pressure members 109g, 309g Rolling grooves (grooves)
111, 211, 311 Lens holding member (movable member)
111g, 211g Rolling groove (groove)
111b, 211b, 311b U groove (groove)
112, 212, 312 Friction member 114 Rolling ball (first guide member)
214, 314 Bearing (first guide member)
150 Vibration wave motor 160 Driving device 10, 20, 30, 50 Optical device A, B Action point G Guide bar (second guide member)
L lens F ₁ , F ₂ , F ₃ pressure F _{12 b} first urging force F _{13 b} second urging force L ₁₂ , L ₁₃ distance

Claims (14)

A vibrator,
A fixing member for holding the vibrator;
A movable member that moves relative to the vibrator;
A pressurizing member that pressurizes the vibrator against the movable member;
A first guide member and a second guide member for guiding the movable member;
In the vibration wave motor with
The first guide member engages with a groove provided in either or both of the fixed member and the movable member, and the second guide member engages with a groove provided in the movable member. A vibration wave motor characterized by guiding the movable member.   The pressurizing member includes a first urging force that urges the movable member against the first guide member, and a second urging force that urges the movable member against the second guide member. The vibration wave motor according to claim 1, wherein the second urging force is smaller than the first urging force.   The distance between the application point of the first urging force and the extension line in the direction in which the pressing force is applied by the pressure member is shorter than the distance between the application point of the second urging force and the extension line. The vibration wave motor according to claim 2, wherein the vibration wave motor is characterized.   In the projection plane in the direction of the relative movement and the direction orthogonal to the direction of the pressing force by the pressure member, the first guide member is 1 in the direction of the relative movement on an extension line of the direction in which the pressing force acts. The vibration wave motor according to claim 1, wherein two vibration wave motors are provided.   At least two of the first guide members are provided in the direction of relative movement, and the pressure force is projected on a projection plane in a direction perpendicular to the direction of relative movement and the direction of pressure applied by the pressure member. The vibration wave motor according to any one of claims 1 to 3, wherein an extension line in a direction in which the first and second guide members extend passes between the two first guide members.   The first guide member is a spherical rolling member, and engages with a groove provided in the movable member and a groove provided on the fixed member. The vibration wave motor according to claim 5.   The first guide member is a rolling member constituted by a bearing having a curved surface portion on an outer diameter, and the curved surface portion engages with a groove portion provided in either the movable member or the fixed member. The vibration wave motor according to any one of claims 1 to 5, wherein   The vibration wave motor according to claim 7, wherein the bearing is pivotally fixed to the fixing member.   The vibration wave motor according to claim 7, wherein the bearing is pivotally fixed to the movable member.   The vibration wave motor according to claim 1, wherein the second guide member is a guide bar.   The friction member that comes into contact with the vibrator is fixed to the movable member, and the vibrator is pressurized against the friction member. The described vibration wave motor.   The vibration wave motor according to any one of claims 1 to 11, wherein the vibration wave motor is an ultrasonic motor using vibration of a frequency in an ultrasonic region.   The drive device provided with the vibration wave motor as described in any one of Claims 1-12.   The drive according to claim 13, further comprising a lens, wherein the lens is fixed to the movable member, and the lens is moved in the optical axis direction by relative movement of the vibrator and the movable member. Optical device using the device.

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