Optical device

Abstract

To provide an optical device capable of reducing sound when moving a lens while improving the efficiency of output, such as the driving force of a lens holding frame, with respect to input from a power source.SOLUTION: An optical device comprises: a holding member that is movable in an optical axis direction; a lead screw that extends in the optical axis direction and is rotationally driven by an actuator; a power transmission member that includes an engagement portion which engages with the lead screw and transmits power in the optical axis direction in response to rotation of the lead screw; a connection member that includes a support portion which rotatably slides and supports the power transmission member, and that is connected to the holding member; a contact member that comes into contact with the power transmission member; first biasing means that biases the contact member from the holding member toward the power transmission member in the optical axis direction; and second biasing means that biases the power transmission member toward the lead screw. In the optical axis direction, the power transmission member is biased toward the connection member by the contact member, and in the optical axis direction, the connection member is biased toward the holding member by the power transmission member.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an optical device. [Background technology]

[0002] In a power transmission mechanism of a lead screw and rack that converts the rotational force of a lead screw into a linear force in the direction of the rotation axis, a sliding friction load is generated between the lead screw and the rack, which reduces the driving efficiency. Patent Document 1 discloses a configuration in which a moving body connected to a lens holding frame supports a circular member using a rotating rolling body such as a bearing, and the circular member engages with the lead screw, and the lead screw and the circular member roll to become a rolling resistance load, thereby reducing the load on the power source. Patent Document 2 discloses a configuration in which a roller is pivoted to an optical head, the roller engages with the lead screw, and the lead screw and the roller roll to become a rolling resistance load, thereby reducing the load on the power source. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2023 / 048093 [Patent Document 2] Japanese Utility Model Application Publication No. 61-040770 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the configuration of Patent Document 1, since a rotating rolling body such as a bearing is used, the rolling noise of the rolling balls is likely to occur, and the driving noise is likely to be large. In addition, since a rotating rolling body such as a bearing is incorporated, the device becomes large. In addition, in the configuration of Patent Document 2, a specific roller support configuration is not particularly described.

[0005] The present invention aims to provide an optical device that can reduce noise when moving a lens while improving the efficiency of output such as driving force of a lens holding frame in response to input such as torque from a power source. [Means for solving the problem]

[0006] An optical device as one aspect of the present invention has a holding member movable in the optical axis direction of the lens, a lead screw extending in the optical axis direction and rotated by an actuator, a power transmission member having an engagement portion that engages with the lead screw and transmits power in the optical axis direction in response to rotation of the lead screw, a connecting member having a support portion that rotatably supports the power transmission member and is connected to the holding member, an abutment member that abuts the power transmission member, first biasing means for biasing the abutment member from the holding member to the power transmission member in the optical axis direction, and second biasing means for biasing the power transmission member to the lead screw, wherein in the optical axis direction, the power transmission member is biased against the connecting member by the abutment member, and in the optical axis direction, the connecting member is biased against the holding member by the power transmission member. Effect of the Invention

[0007] According to the present invention, it is possible to provide an optical device that can reduce noise when moving a lens while improving the efficiency of the output of the driving force, etc., of a lens holding frame in response to an input of torque, etc. from a power source. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is an explanatory diagram of an optical device according to a first embodiment. [Diagram 2] FIG. 2 is a perspective view of a power transmission member according to the first embodiment. [Diagram 3] 1A and 1B are an exploded perspective view and a perspective view of a power transmission member according to a first embodiment. [Figure 4] FIG. 2 is an explanatory diagram of a power transmission member according to the first embodiment. [Diagram 5] FIG. 4 is an explanatory diagram of loss reduction in the first embodiment. [Figure 6]FIG. 4 is an explanatory diagram of an optical device according to a second embodiment. [Figure 7] FIG. 6 is a cross-sectional view of a power transmission member according to a second embodiment. [Figure 8] FIG. 11 is an explanatory diagram of an optical device according to a third embodiment. [Figure 9] FIG. 11 is a perspective view of a power transmission member according to a third embodiment. [Figure 10] 13A and 13B are an exploded perspective view and a perspective view showing the configuration of a power transmission member according to a third embodiment. [Figure 11] 13 is an explanatory diagram of a power transmission member according to a third embodiment. FIG. [Figure 12] FIG. 13 is an explanatory diagram of a biased state in the third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals are used to refer to the same components, and duplicated descriptions will be omitted. [First embodiment] (1-1) Overall structure Fig. 1(a) is a perspective view of the optical device 100 excluding the fixed barrel 101, and Fig. 1(b) is a cross-sectional view of the optical device 100. Figs. 2(a) and 2(b) are perspective views of the power transmission member 110 enlarged and viewed from different directions, excluding the lead screw 108. In this embodiment, the direction parallel to the optical axis of the lens 102 (optical axis direction) is the X1 direction, which is perpendicular to the X1 direction, the up-down direction of the optical device 100 is the Y1 direction, and the direction perpendicular to the X1 and Y1 directions is the Z1 direction, which are indicated by arrows in the figures.

[0010] The optical device 100 includes a lens holding frame (holding member) 103 that holds a lens 102, and a cylindrical main guide bar 104 and a sub guide bar 105 whose axial direction is parallel to the X1 direction and linearly guides the lens holding frame 103 in the optical axis direction of the lens 102. The optical device 100 also includes a sheet metal part 107, a power source (actuator) 106 fixed to the sheet metal part 107, and a lead screw 108 whose rotation axis direction is parallel to the X1 direction (extends in the X1 direction) and which is connected to the power source 106. When power is input to the power source 106 from a power source or the like (not shown), the lead screw 108 is driven to rotate. In this embodiment, a stepping motor is used as the power source 106, but a different power source may be used as long as it can drive the lead screw 108 to rotate. Furthermore, the optical device 100 has a connecting member 109 connected to the lens holding frame 103, a power transmission member 110 rotatably and slidingly supported by the connecting member 109, an abutment member 111 that abuts against the power transmission member 110, and a compression torque spring 112.

[0011] Both ends of main guide bar 104 and sub guide bar 105 are fixed to fixing portions (not shown) of fixed barrel 101. Furthermore, sheet metal portion 107 and power source 106 fixed to sheet metal portion 107 are fixed to fixed barrel 101.

[0012] The lens holding frame 103 includes guide holes 103a and 103b that engage with the main guide bar 104, and a guide groove 103u that abuts against the sub-guide bar 105. The lens holding frame 103 is supported by the guide holes 103a and 103b and the main guide bar 104 so as to be movable in the X1 direction, and the guide groove 103u and the sub-guide bar 105 prevent the main guide bar 104 from rotating around its axis. In this embodiment, the main guide bar 104 and the sub-guide bar 105 are used as guide means for the lens holding frame 103, but a different configuration may be used as long as the lens holding frame 103 can be supported so as to be movable in the X1 direction. The lens holding frame 103 includes connecting holes 103c and 103d that are parallel to the X1 direction and connect the connecting member 109. The connecting member 109 is connected so as to be rotatable around the axis of the connecting holes 103c and 103d.

[0013] 3(a) and 3(b) are exploded perspective views of the components around the power transmission member 110, as viewed from different directions. FIG. 3(c) and FIG. 3(d) are perspective views of the components around FIG. 3(a) and FIG. 3(b), respectively, assembled together. FIG. 4(a) is an enlarged view of the power source 106 and its surroundings of the optical device 100, excluding the fixed barrel 101, as viewed from the opposite direction to the X1 direction. FIG. 4(b) and FIG. 4(c) are cross-sectional views taken along the lines AA and BB, respectively, of FIG. 4(a). FIG. 4(d) is a cross-sectional view taken along the line BB, in the case where the support structure for the power transmission member 110 is different.

[0014] The connecting member 109 includes a sliding support shaft portion 109a and a sliding support surface portion 109b that support the power transmission member 110 rotatably and slidingly around an X2 axis parallel to the X1 direction. The sliding support shaft portion 109a and the sliding support surface portion 109b function as a support portion that supports the power transmission member 110 rotatably and slidingly. The connecting member 109 also includes connecting shaft portions 109c and 109d that are connected to the connecting hole portions 103c and 103d rotatably around an X3 axis parallel to the X1 direction. The connecting member 109 also includes an engagement shaft portion 109e that engages with the abutting member 111, a rotation restriction portion 109g that restricts the relative rotation with the abutting member 111, and a bias portion 109f to which the biasing force of the torque spring portion 112b of the compression torque spring 112 is transmitted. Furthermore, the connecting member 109 includes a conical portion 109h that comes into contact with the lens holding frame 103 in the X1 direction.

[0015] The power transmission member 110 includes a sliding hole portion 110a and a sliding surface portion 110b that are rotatably and slidingly supported on the connecting member 109 around the X2 axis, and a sliding surface portion 110c that is rotatably and slidingly abutted against the abutment member 111. The power transmission member 110 also includes a full-circumferential tooth portion (engagement portion) 110d that meshes with the thread portion of the lead screw 108.

[0016] The abutment member 111 includes an engagement hole portion 111a that engages with the connecting member 109 on the X3 axis, and a rotation restricting portion 111c that restricts relative rotation with the connecting member 109 about the X3 axis. The abutment member 111 also includes a sliding abutment surface portion 111b that rotatably and slidingly contacts the power transmission member 110, and a spring shaft portion 111d into which the compression spring portion 112a of the compression torque spring 112 is incorporated.

[0017] The compression torque spring 112 includes a compression spring portion (first biasing means) 112a and a torque spring portion (second biasing means) 112b. The compression spring portion 112a biases the contact member 111 from the lens holding frame 103 to the power transmission member 110 in the X1 direction. The torque spring portion 112b biases both the lens holding frame 103 and the connecting member 109 in a direction perpendicular to the X1 direction, which is a direction perpendicular to the optical axis, and biases the power transmission member 110 to the lead screw 108.

[0018] The biasing state of each part in the direction perpendicular to the X1 direction will be described below. The connecting hole parts 103c and 103d are connected to the connecting shaft parts 109c and 109d so as to be rotatable around the X3 axis, and are biased by the torque spring part 112b to the offset part 109f with a biasing force S1 as shown in FIG. 3(c). The biasing force S1 biases the sliding support shaft part 109a to the side of the sliding hole part 110a of the power transmission member 110 with a biasing force S2 as shown in FIG. 4(c). The biasing force S2 biases the full-circumference tooth part 110d to the thread part of the lead screw 108 with biasing forces S3 and S3' as shown in FIG. 4(c). At this time, the connecting member 109 rotates around the X3 axis, so that the full-circumference tooth part 110d meshes with the lead screw 108. As described above, by biasing the connecting member 109 with the torque spring portion 112b, the thread portion of the lead screw 108 and the full-circumferential teeth portion 110d can be engaged without any backlash.

[0019] Furthermore, torque spring portion 112b biases lens holding frame 103 against main guide bar 104 and sub guide bar 105. This makes it possible to suppress play between guide hole portions 103a, 103b and main guide bar 104 in a direction perpendicular to the X1 direction, and play between guide groove portion 103u and sub guide bar 105 in a direction perpendicular to the X1 direction.

[0020] The biasing state of each component in the X1 direction will be described below. The abutting member 111 is engaged with the engaging shaft portion 109e at the engaging hole portion 111a, and rotation around the X3 axis is restricted by the rotation restricting portions 109g and 111c, so that the abutting member 111 is configured to be movable only in a direction parallel to the X3 axis. The spring shaft portion 111d is biased by the compression spring portion 112a with a biasing force S4 of FIG. 4(b). The biasing force S4 causes the abutting member 111 to move in a direction parallel to the X3 axis, and the sliding abutting surface portion 111b is biased toward the sliding surface portion 110c. The other end of the compression spring portion 112a abuts against the lens holding frame 103, so that the lens holding frame 103 receives a biasing force S4' in the X1 direction opposite to the biasing force S4. In addition, the biasing force S5 applied to the sliding surface portion 110c biases the sliding surface portion 110b toward the sliding support surface portion 109b. Furthermore, the conical portion 109h is urged toward the connecting hole portion 103c by the urging force S6 applied to the sliding support surface portion 109b. As described above, the compression spring portion 112a urges the connecting member 109, the power transmission member 110, and the abutting member 111 toward the lens holding frame 103 in the X1 direction without any backlash.

[0021] Hereinafter, a power transmission member 110' having a different support configuration from the power transmission member 110 of FIG. 4(d) will be described. The power transmission member 110' has sliding shaft portions 110b' and 110c'. The sliding shaft portions 110b' and 110c' abut against a conical bearing 109a' provided on the connecting member 109' and a conical bearing 111b' of the abutment member 111', respectively. The conical bearing 109a' functions as a support portion that rotatably supports the power transmission member 110. In the configuration of FIG. 4(d), the biasing state in the X1 direction and the direction perpendicular to the X1 direction is the same as the state in FIG. 3 and FIG. 4(a) to FIG. 4(c), so a description thereof will be omitted.

[0022] The support structure for the power transmission member may be the structure shown in Fig. 4(c) or the structure shown in Fig. 4(d) as long as the structure can rotatably support the power transmission member on the contact surface that contains the rotation axis of the power transmission member. It is desirable to provide the contact surface near the center of the rotation axis of the power transmission member, since this increases the effect of load reduction, which will be described later.

[0023] The engagement configuration between the power transmission member 110 and the lead screw 108 will be described below. The power transmission member 110 has a full-circumference toothed portion 110d on the outer diameter side. The full-circumference toothed portion 110d is biased so as to mesh with the threaded portion of the lead screw 108 that is rotationally driven by the power source 106. The full-circumference toothed portion 110d is configured to be connected to the entire circumference of the outer diameter side of the power transmission member 110, and is biased so as to always mesh with the lead screw 108 even if the power transmission member 110 slides and rotates relative to the connecting member 109. However, as long as the lead screw 108 and the power transmission member 110 have a shape that allows them to mesh with each other, the engagement configuration between the lead screw 108 and the power transmission member 110 may have a different shape. Also, as described above, the power transmission member 110 is biased to be rotatable around the X2 axis from the sliding support shaft portion 109a at the sliding hole portion 110a, and is biased to be rotatable so as to be sandwiched between the sliding support surface portion 109b and the sliding abutment surface portion 111b.

[0024] With the above configuration, when the lead screw 108 is rotationally driven by the power source 106, the thread portion of the lead screw 108 appears to move in the direction of the rotation axis of the lead screw 108. Then, the full-circumference teeth portion 110d meshing with the thread portion rolls and rotates while meshing with the lead screw 108, and the lens 102, lens holding frame 103, lens connecting member 109, power transmission member 110, abutment member 111, and compression torque spring 112 move in the X1 direction. The configuration of this embodiment satisfies the following conditional formula (1).

[0025] T1>T2 (1) Here, T1 is the rotational resistance torque acting on the full circumference teeth portion 110d when the power transmission member 110 meshes with the lead screw 108 and slides. T2 is the rotational resistance torque acting on the sliding support shaft portion 109a when the connecting member 109 and the power transmission member 110 rotate relatively around the X2 axis. By satisfying the conditional formula (1), the power transmission member 110 does not slide while meshing with the lead screw 108, but rolls and rotates while meshing with the lead screw 108, and rotates relatively to the connecting member 109. For example, a case will be described where the friction coefficient μ1 between the power transmission member 110 and the lead screw 108 is the same as the friction coefficient μ2 between the power transmission member 110 and the connecting member 109, the diameter of the sliding hole portion 110a is D1, and the diameter of the full circumference teeth portion 110d is D2. 4(c), the rotational resistance torque T1 is proportional to the sum of the diameter D2 and the biasing forces S3, S3', and the rotational resistance torque T2 is proportional to the diameter D1 and the biasing force S2. Since the diameter D2 is larger than the diameter D1, and the sum of the biasing forces (normal forces) S3, S3' is larger than the biasing force S2 (details will be described later), the rotational resistance torque T1 is larger than the rotational resistance torque T2, and the power transmission member 110 rotates relative to the connecting member 109. (1-2) Loss reduction First, the forces acting on the power transmission member 110 of this embodiment will be described. FIG. 5(a) shows forces F1 and F6 that the power transmission member 110 receives from the connecting member 109, forces F2 and F3 that the power transmission member 110 receives from the lead screw 108, and a force F8 that the power transmission member 110 receives from the contact member 111. These forces are generated by the biasing forces S1 and S4 of the compression torque spring 112. FIG. 5(b) is a cross-sectional view taken along the line CC in FIG. 5(a). FIG. 5(b) shows a resistance force F4 that is generated when the lead screw 108 rotates in the direction G1 and the power transmission member 110 rotates in the direction G2 while receiving the force F1, and a tangential force F5 that is necessary for the lead screw 108 to rotate and drive the power transmission member 110. FIG. 5(c) is a cross-sectional view taken along the line DD in FIG. 5(a). FIG. 5(c) shows a resistance force F7 that is generated when the lead screw 108 rotates in the direction G1 and the power transmission member 110 rotates in the direction G2 while receiving the force F6. Fig. 5(d) is a cross-sectional view taken along line EE in Fig. 5(a). Fig. 5(d) shows a resistance force F9 that is generated when the lead screw 108 rotates in the direction G1 and the power transmission member 110 rotates in the direction G2 while receiving a force F8.

[0026] Loss reduction will be described below. Here, D0 is the diameter of the lead screw 108. D1 is the diameter of the sliding hole portion 110a. D2 is the diameter of the full-circumference teeth portion 110d that meshes with the lead screw 108. D3 is the diameter of the area where the connecting member 109 and the sliding surface portion 110b abut. D4 is the diameter of the area where the abutting member 111 and the sliding surface portion 110c abut. As shown in FIG. 4(c), the diameter of the sliding hole portion 110a is divided into two stages, D1 and D1', but since the diameters D1 and D1' are almost the same, only the diameter D1 will be used below for simplicity.

[0027] The force F1 is a force that the connecting member 109 imparts to the power transmission member 110 as a result of the torque spring portion 112b biasing the offset portion 109f. The forces F2 and F3 are forces that the lead screw 108 imparts to the power transmission member 110 as a result of the power transmission member 110 biasing the lead screw 108 by the force F1. Furthermore, the forces F2 and F3 are forces in a direction perpendicular to the engagement surface because the lead screw 108 and the full-circumference tooth portion 110d engage with each other at a thread opening angle H1. In this embodiment, the thread opening angle H1 of the lead screw 108 is 60°, and the forces F2 and F3 are the same in magnitude as the force F1 due to the balance of forces.

[0028] 5(b), the rotational resistance torque of the power transmission member 110 around the X2 axis generated by the force F1 will be described below. When the lead screw 108 is rotationally driven in the direction G1, the configuration of this embodiment satisfies conditional expression (1), and therefore the power transmission member 110 rolls and rotates while meshing with the lead screw 108. At this time, when the power transmission member 110 rotates in the direction G2 while receiving the force F1, a resistance force F4 is generated between the connecting member 109 and the power transmission member 110. At this time, the rotational resistance torque T4 of the power transmission member 110 around the X2 axis caused by the resistance force F4 is expressed by the following formula (2).

[0029] T4 = F4 × (D1 / 2) (2) Further, a tangential force F5 required for the lead screw 108 to rotate the power transmission member 110 generating the rotational resistance torque T4 satisfies the following conditional expression (3).

[0030] F5>F4 / (D2 / D1) (3) From the above, the rotational driving force T5 required for the lead screw 108 to rotate the power transmission member 110 is expressed by the following formula (4).

[0031] T5=F5×D0 / 2 (4) From conditional expressions (3) and (4), the rotational driving force T5 satisfies the following conditional expression (5) using the resistance force F4.

[0032] T5>(F4 / (D2 / D1))×(D0 / 2) (5) According to the conditional formula (5), the rotational driving force T5 required for the lead screw 108 to rotate the power transmission member 110 is reduced by the ratio of the diameter D2 to the diameter D1. This means that the resistance force F4 at the diameter D1 generated between the connecting member 109 and the power transmission member 110 is reduced by the ratio of the diameter D2 to the diameter D1 at the position of the diameter D2 of the full circumference tooth portion 110d. Therefore, the tangential force F5 required for the lead screw 108 to rotate the power transmission member 110 is reduced by the ratio of the diameter D2 to the diameter D1. However, if the diameter D2 is increased, the ratio of the diameter D2 to the diameter D1 increases and the tangential force F5 is reduced, but the moment of inertia of the power transmission member 110 increases and the optical device 100 becomes larger. Therefore, it is necessary to set an appropriate value for the ratio of the diameter D2 to the diameter D1. Here, it is desirable to configure the ratio of diameter D2 to diameter D1 so as to satisfy the following conditional expression (6) so that the optical device 100 does not become large and the moment of inertia of the power transmission member 110 does not increase too much.

[0033] 1 <D2 / D1<100 (6) 5(a) and 5(c), the rotational resistance torque of the power transmission member 110 about the X2 axis generated by the force F6 will be described below. The force F6 is a force that the power transmission member 110 receives from the connecting member 109, and is a force with which the compression spring portion 112a urges the contact member 111. When the power transmission member 110 rotates in the direction G2 while receiving the force F6, a resistance force F7 is generated between the connecting member 109 and the power transmission member 110. At this time, the rotational resistance torque T7 of the power transmission member 110 about the X2 axis caused by the resistance force F7 is expressed by the following equation (7).

[0034] T7=F7×(D3 / 2) (7) By making the sliding support surface portion 109b spherical or the like, the diameter D3 becomes almost 0, and the rotational resistance torque T7 also becomes a very small value (almost 0). As described above, the resistance force F4 due to the force F1 generated at the diameter D1 is reduced at the position of the diameter D2 by the ratio of the diameter D2 to the diameter D1. Similarly, the resistance force F7 at the diameter D3 generated between the connecting member 109 and the power transmission member 110 is reduced at the position of the diameter D2 of the full circumference tooth portion 110d by the ratio of the diameter D2 to the diameter D3. Therefore, the rotational resistance torque T7 has almost no effect on the tangential force F5 required for the lead screw 108 to rotate the power transmission member 110, and can be ignored.

[0035] 5(a) and 5(d), the rotational resistance torque of the power transmission member 110 about the X2 axis generated by the force F8 will be described below. The force F8 is a force that the power transmission member 110 receives from the abutting member 111, and is the same magnitude as the force with which the compression spring portion 112a urges the abutting member 111. When the power transmission member 110 rotates in the direction G2 while receiving the force F8, a resistance force F9 is generated between the power transmission member 110 and the abutting member 111. At this time, the rotational resistance torque T9 of the power transmission member 110 about the X2 axis caused by the resistance force F9 is expressed by the following equation (8).

[0036] T9=F9×(D4 / 2) (8) By making the sliding surface portion 110c spherical, the diameter D4 becomes almost 0, and the rotational resistance torque T9 also becomes a very small value (almost 0). As described above, the resistance force F4 due to the force F1 generated at the diameter D1 is reduced at the position of the diameter D2 by the ratio of the diameter D2 to the diameter D1. Similarly, the resistance force F9 at the diameter D4 generated between the power transmission member 110 and the abutting member 111 is reduced at the position of the diameter D2 of the full circumference tooth portion 110d by the ratio of the diameter D2 to the diameter D4. Therefore, the rotational resistance torque T9 has almost no effect on the resistance force F9, and can be ignored.

[0037] Hereinafter, the rotational resistance torque in the case where the power transmission member 110 does not rotate will be described. In the case where the power transmission member 110 is fixed to the connecting member 109 and the lead screw 108 rotates, the power transmission member 110 engages with the thread of the lead screw 108, and a resistance force such as friction is generated against the forces F2 and F3 in FIG. 5(a). The generated resistance force is the tangential force of the lead screw 108 required to rotate the power transmission member 110. For example, if the friction coefficient between the lead screw 108 and the power transmission member 110 is μ, a friction force of (F2+F3)×μ is generated. In addition, when the opening angle H1 of the screw is 60°, the forces F1, F2, and F3 are equal as described above, and the friction force is 2×F1×μ. In this case, the torque required to rotate the lead screw 108 is greater than the value F1×μ×D0.

[0038] In this embodiment, since the lead screw 108 and the power transmission member 110 rotate by rolling, no resistance forces such as friction due to forces F2 and F3 are generated, but a resistance force F4 such as friction due to force F1 is generated. If the friction coefficient between the connecting member 109 and the power transmission member 110 is μ, the force F4 is F1×μ. At this time, the rotational driving force T5 required for the lead screw 108 to rotationally drive the power transmission member 110 is a value larger than {(F1×μ) / (D2 / D1)}×(D0 / 2) from conditional formula (5).

[0039] As described above, when the power transmission member 110 is configured to be rotatable, it is possible to rotate the lead screw 108 with a smaller load and drive the lens holding frame 103 in the X1 direction compared to when the power transmission member 110 is fixed. This makes it possible to reduce the resistance forces F4, F7, and F9 by values ​​D2 / D1, D2 / D3, and D2 / D4, respectively, and to reduce the loss that occurs when transmitting force from the lead screw 108 to the power transmission member 110. Therefore, it is possible to increase the output of the driving force and the like possessed by the lens holding frame 103 relative to the torque input transmitted from the power source 106 to the lead screw 108, and to provide an optical device 100 with improved driving efficiency.

[0040] Hereinafter, the effect obtained by rotatably and slidingly supporting the power transmission member 110 by the connecting member 109 and the abutting member 111 will be described. In this embodiment, in the direction perpendicular to the X1 direction, the sliding hole portion 110a is rotatably and slidingly supported by the connecting member 109, and in the X1 direction, the sliding surface portions 110b, 110c are rotatably and slidingly supported by being sandwiched between the connecting member 109 and the abutting member 111. Therefore, all the support portions of the power transmission member 110 are sliding bearings, and there is no need to use a rolling structure such as a bearing. Therefore, even if the power transmission member 110 rotates, it is possible to reduce vibration noise and driving noise, and to miniaturize the optical device 100.

[0041] As described above, the configuration of this embodiment can provide a small-sized optical device with reduced vibration noise and driving noise while improving drive efficiency by reducing load loss in power transmission. [Second embodiment] In this embodiment, only the configurations different from the first embodiment will be described, and the description of the common configurations will be omitted. Note that, although numbers in the 200 range are given to parts, shapes, etc. in this embodiment, parts and shapes similar to those in the first embodiment are given the same last two digits as those in the first embodiment.

[0042] Fig. 6(a) is a perspective view of the optical device 200 excluding the fixed barrel 201, and Fig. 6(b) is a cross-sectional view of the optical device 200. In this embodiment, the direction parallel to the optical axis of the lens 202 (optical axis direction) is the X5 direction, the direction perpendicular to the X5 direction, the up-down direction of the optical device 200 is the Y2 direction, and the direction perpendicular to the X5 direction and the Y2 direction is the Z2 direction, which are indicated by arrows in the figure.

[0043] The optical device 200 includes a lens holding frame 1203 that holds a lens 202, and a cylindrical main guide bar 204 and a sub guide bar 205 whose axial direction is parallel to the X5 direction and linearly guides the lens holding frame 203 in the optical axis direction of the lens 202. The optical device 200 also includes a sheet metal part 207, a power source 206 fixed to the sheet metal part 207, and a lead screw 208 whose rotation axis direction is parallel to the X5 direction and connected to the power source 206. When power is input to the power source 206 from a power source or the like (not shown), the lead screw 208 is driven to rotate. The optical device 200 also includes a connecting member 109 connected to the lens holding frame 203, and a sliding shaft member 213 fixed to the connecting member 209 by a fixing nut 214. Furthermore, the optical device 200 includes a power transmission member 210 rotatably and slidingly supported by the sliding shaft member 213 , a contact member 211 that contacts the power transmission member 210 , and a compression torque spring 212 .

[0044] 7, a detailed configuration of the connecting member 209 and the sliding shaft member 213 and an effect obtained by configuring the sliding shaft member 213 as a separate part from the connecting member 209 will be described.

[0045] The connecting member 209 has an engagement hole portion 209i with which the sliding shaft member 213 engages, and a through hole portion 209j through which the sliding shaft member 213 penetrates. The sliding shaft member 213 has a sliding support shaft portion 213a and a sliding support surface portion 213b that support the power transmission member 210 so as to be rotatable around an X6 axis parallel to the X5 direction. The sliding shaft member 213 also has an engagement shaft portion 213c that engages with the connecting member 209, and a fixing screw portion 213d that is connected to a fixing nut 214.

[0046] Hereinafter, the effect obtained by configuring the sliding shaft member 213 as a separate part from the connecting member 209 will be described. D5 is the diameter of the sliding hole portion 210a and the sliding support shaft portion 213a. D6 is the diameter of the full-circumferential tooth portion (engagement portion) 210d that meshes with the lead screw 208. As described above, the load can be reduced by the ratio of the diameter D6 to the diameter D5. By making the diameter D5 as small as possible, the ratio of the diameter D6 to the diameter D5 can be increased, and the load reduction effect can be increased. In this embodiment, by configuring the sliding shaft member 213 from a part with high strength such as metal, the diameter D5 of the sliding support shaft portion 213a can be reduced, and the load reduction effect can be further increased. In addition, by configuring the sliding shaft member 213 from a part with high strength such as metal, wear due to the sliding rotation of the power transmission member 210 is less likely to occur, and the friction coefficient with the power transmission member 210 can be reduced. Furthermore, as in the first embodiment, there is no need to use a rolling configuration such as a bearing, so vibration noise and driving noise can be reduced and the optical device 200 can be made smaller.

[0047] As described above, the configuration of this embodiment can provide a compact optical device 200 that reduces the load loss in power transmission, thereby improving drive efficiency, while producing less vibration noise and drive noise. [Third embodiment] (3-1) Overall structure In this embodiment, only the configurations different from the first and second embodiments will be described, and the description of the common configurations will be omitted. Note that, in this embodiment, numbers in the 300s are given to parts, shapes, etc., but parts and shapes similar to those in the first embodiment are given the same last two digits as those in the first embodiment.

[0048] Fig. 8(a) is a perspective view of the optical device 300 excluding the fixed barrel 301, and Fig. 8(b) is a cross-sectional view of the optical device 300. Figs. 9(a) and 9(b) are perspective views of the power transmission member 310 enlarged and viewed from different directions, excluding the lead screw 308. In this embodiment, the direction parallel to the optical axis of the lens 302 (optical axis direction) is the X8 direction, which is perpendicular to the X8 direction, the up-down direction of the optical device 300 is the Y3 direction, and the direction perpendicular to the X8 and Y3 directions is the Z3 direction, which are indicated by arrows in the figure.

[0049] The optical device 300 includes a lens holding frame 303 that holds a lens 302, and a cylindrical main guide bar 304 and a sub guide bar 305 whose axial direction is parallel to the X8 direction and linearly guides the lens holding frame 303 in the optical axis direction of the lens 302. The optical device 300 also includes a sheet metal part 307, a power source 306 fixed to the sheet metal part 307, and a lead screw 308 whose rotation axis direction is parallel to the X8 direction and connected to the power source 306. When power is input to the power source 306 from a power source or the like (not shown), the lead screw 308 is driven to rotate. The optical device 300 also includes a connecting member 309 connected to the lens holding frame 303, a power transmission member 310 rotatably and slidingly supported by the connecting member 309, an abutting member 311 that abuts against the power transmission member 310, and a compression torque spring 312. Furthermore, the optical device 300 has a ball 315 incorporated in the abutting member 311 and a pinching torque spring (third biasing means) 316.

[0050] Hereinafter, there will be described detailed shapes of the connecting member 309, the contact member 311, the compression torque spring 312, the ball 315, and the sandwiching torque spring 316. The other parts have the same shapes as in the first embodiment, so description thereof will be omitted.

[0051] Figures 10(a) and 10(b) are exploded perspective views of the components around the power transmission member 310, as seen from different directions. Figures 10(c) and 10(d) are perspective views of the assembled parts of Figures 10(a) and 10(b), respectively. Figures 11(a) and 11(b) are cross-sectional views taken along lines FF and GG, respectively, in Figure 8(a).

[0052] In addition to the same configuration as in the first embodiment, the connecting member 309 includes an engagement shaft portion 309e in which the sandwiching torque spring 316 and the abutting member 311 are assembled, and a rotation restricting portion 309g that restricts relative rotation between the connecting member 309 and the abutting member 311 around the X10 axis. The connecting member 309 also includes a sandwiching portion 309k to which the biasing force of the sandwiching torque spring 316 is transmitted.

[0053] In addition to the same shape as in the first embodiment, the abutment member 311 includes a rotation restricting portion (second abutment portion) 311c that restricts the relative rotation with the connecting member 309 around the X10 axis, and a clamping portion 311i to which the biasing force of the clamping torque spring 316 is transmitted. The abutment member 311 also includes an abutment hole portion 311e with which the ball 315 is engaged and fixed, and an abutment surface portion 311f that abuts against the ball 315 in the X8 direction. The abutment member 311 also includes a facing portion 311g that faces the power transmission member 310 so as to sandwich the lead screw 308 and is separated from the lead screw 308 by a predetermined gap. The abutment member 311 also includes a facing tooth portion (third abutment portion) 311h that is provided on the facing portion 311g and can be engaged with the thread portion of the lead screw 308.

[0054] The compression torque spring 312 includes a compression spring portion (first biasing means) 312a and a torque spring portion (second biasing means) 312b. The compression spring portion 312a biases the contact surface portion (first contact portion) 311f of the contact member 311 from the lens holding frame 303 to the power transmission member 310 in the X8 direction. The torque spring portion 312b biases both the lens holding frame 303 and the connecting member 309 in a direction perpendicular to the X8 direction, which is a direction perpendicular to the optical axis, and biases the power transmission member 310 to the lead screw 308.

[0055] The sandwiching torque spring 316 has a first end which biases the sandwiching portion 309k and a second end which biases the sandwiching portion 311i, and is assembled into the engagement shaft portion 309e.

[0056] The biasing state between the parts will be described below. The biasing state of each part in the direction perpendicular to the X8 direction by the torque spring part 312b is the same as that of the first embodiment, so the description will be omitted. The biasing state of each part in the X8 direction by the compression spring part 312a is different in that the ball 315 is integrally incorporated and fixed in the abutment member 311 and abuts against the power transmission member 310, but the other configurations are the same as those of the first embodiment, so the description will be omitted.

[0057] Since the engagement hole 311a is engaged with the engagement shaft 309e on the X10 axis, the abutting member 311 can rotate around the X10 axis relative to the connecting member 309. In addition, the clamping torque spring 316 biases the clamping portions 309k and 311i, which biases the rotation restricting portions 309g and 311c so that they come into contact with each other. At this time, the forces at which the rotation restricting portions 309g and 311c come into contact with each other are indicated as F14' and F15' in the drawing.

[0058] As a result, in the direction perpendicular to the X8 direction, the power transmission member 310 is biased toward the lead screw 308 by the torque spring portion 312b, while the contact member 311 is biased toward the power transmission member 310 by the sandwiching torque spring 316. At this time, as described above, the opposing portion 311g and the opposing teeth portion 311h are spaced apart from the lead screw 308 by a predetermined gap. The gap is configured to be smaller than the depth of engagement in the direction perpendicular to the X8 direction, where the full-circumferential teeth portion (engagement portion) 310d and the thread portion of the lead screw 308 engage with each other. (3-2) About skipped teeth A tooth jump in which the full-circumferential tooth portion 310d exceeds the thread portion of the lead screw 308 will be described. First, referring to FIG. 12, the biasing state of the power transmission member 310 when an external force in the X8 direction is applied to the lens 302 will be described. FIGS. 12(a) to 12(c) are enlarged views of region I in FIG. 11(b). FIGS. 12(a) and 12(b) show a state in which the power transmission member 310 does not separate from the lead screw 308 in a direction perpendicular to the X8 direction. FIG. 12(c) shows a state in which the power transmission member 310 separates from the lead screw 308 in a direction perpendicular to the X8 direction. FIG. 12(d) is a view of FIG. 12(c) seen from the opposite direction to the X8 direction. FIG. 12(e) is an explanatory view of a biasing state just before tooth jumping seen from the opposite direction to the X8 direction. 12(a), when no external force is acting on the lens 302, the power transmission member 310 receives a biasing force F11 from the connecting member 309 and normal forces F12, F12' perpendicular to the inclined surface of the opening angle of the thread of the lead screw 308 through the torque spring portion 312b. The resultant force of the biasing force F11 and the normal forces F12, F12' is in balance.

[0059] Next, a case where an external force F10 acts on the lens 302 will be described. When an external force F10 occurs on the lens 302 in the X8 direction, the external force F10 is transmitted to the lens holding frame 303, transmitted from the lens holding frame 303 to the connecting member 309 or the abutting member 311, and transmitted from the connecting member 309 or the abutting member 311 to the power transmission member 310. At this time, since the lead screw 308 is fixed in the X8 direction, the power transmission member 310 receives the external force F10 and a resistance to the external force F10 from one of the inclined surfaces of the opening angle of the thread of the lead screw 308. Specifically, as shown in FIG. 12(b), the normal force F12 perpendicular to the inclined surface of the opening angle of the thread of the lead screw 308 increases as a resistance to the external force F10. Also, since the resultant force of the normal forces F12 and F12' in the direction perpendicular to the X8 direction is in balance with the biasing force F11, the normal force F12' decreases. When the resultant force of the normal forces F12 and F12' in the direction perpendicular to the X8 direction is equal to or smaller than the biasing force F11, the power transmission member 310 is maintained in a state of being biased against the lead screw 308 as shown in FIG. 12(b). On the other hand, when the resultant force of the normal forces F12 and F12' in the direction perpendicular to the X8 direction is greater than the biasing force F11, the power transmission member 310 moves away so as to climb the slope of the opening angle of the thread of the lead screw 308. After that, the power transmission member 310 is in the state shown in FIG. 12(c), and the normal force F12' disappears. At this time, the connecting member 309 supporting the power transmission member 310 rotates around the X10 axis and moves away from the lead screw 308, so that the abutting member 311 biased against the connecting member 309 by the rotation restricting portion 311c also rotates around the X10 axis together with the connecting member 309. When the connecting member 309 and the abutting member 311 rotate around the X10 axis, the opposing teeth portion 311h abuts against the lead screw 308. As described above, in the state of Fig. 12(a), the gap between the lead screw 308 and the opposing teeth portion 311h is smaller than the meshing depth (engagement height) in a direction perpendicular to the X8 direction where the full-circumference teeth portion 310d meshes with the thread portion of the lead screw 308. Therefore, when the connecting member 309 rotates around the X10 axis, the opposing teeth portion 311h abuts against the lead screw 308 before the full-circumference teeth portion 310d completely passes over the thread portion of the lead screw 308.

[0060] As a result, both the full-circumferential teeth portion 310d and the opposing teeth portion 311h come into contact with the lead screw 308, and the opposing teeth portion 311h receives a normal force F13 perpendicular to the inclined surface of the opening angle of the thread of the lead screw 308. Therefore, the power transmission member 310 and the abutting member 311 receive normal forces F12 and F13 from the lead screw 308, respectively. Therefore, a separating force is generated that separates both the power transmission member 310 and the abutting member 311 from the lead screw 308 in a direction perpendicular to the X8 direction. On the other hand, when the opposing teeth portion 311h comes into contact with the lead screw 308, the biasing forces F14' and F15' of the sandwiching torque spring 316 decrease as shown in FIG. 11(a), and the biasing forces F14 and F15 shown in FIG. 12(b) and FIG. 12(c) increase. This is because the biasing force of the sandwiching torque spring 316 acts as biasing forces F14', F15' that sandwich the rotation restricting portions 309g, 311c, and also acts as biasing forces F14, F15 that sandwich the lead screw 308 between the circumferential teeth portion 310d and the opposing teeth portion 311h. In the direction perpendicular to the X8 direction, when the normal forces F12, F13 are smaller than the biasing forces F14, F15, respectively, the circumferential teeth portion 310d and the opposing teeth portion 311h do not move any further away from the lead screw 308. On the other hand, in the direction perpendicular to the X8 direction, when the normal forces F12, F13 are larger than the biasing forces F14, F15, respectively, the circumferential teeth portion 310d and the opposing teeth portion 311h move further away from the lead screw 308. At this time, as shown in Fig. 12(d), the entire biasing force of the sandwiching torque spring 316 acts as biasing forces F14, F15 that sandwich the lead screw 308 between the full-circumferential tooth portion 310d and the opposing tooth portion 311h. Also, the rotation restricting portions 309g, 311c are no longer in contact, and the biasing forces F14', F15' no longer act. In this case, the full-circumferential tooth portion 310d and the opposing tooth portion 311h gradually climb the inclined surface of the opening angle of the thread of the lead screw 308, and eventually a tooth jump phenomenon occurs in which they exceed the thread portion of the lead screw 308.

[0061] As described above, there are three engagement states of the lead screw 308, the power transmission member 310, and the contact member 311 depending on the magnitude of the external force F10. The first engagement state (first state) is a state in which the external force F10 is not applied with a force equal to or greater than a predetermined value in a direction perpendicular to the X8 direction, and the resultant force of normal forces F12, F12', which increase or decrease due to the external force F10, is equal to or less than the biasing force F11. At this time, the full circumference teeth portion 310d is engaged with the thread portion of the lead screw 308, and the counter teeth portion 311h is not in contact with the lead screw 308. This state also includes the case where there is no external force F10. The second engagement state (second state) and the third engagement state are states in which the external force F10 is applied with a force equal to or greater than a predetermined value in a direction perpendicular to the X8 direction. More specifically, the second engagement state is a state in which the resultant force of the normal forces F12 and F12' in the direction perpendicular to the X8 direction is greater than the biasing force F11, the opposed teeth 311h abuts against the lead screw 308, and the normal forces F12 and F13 are equal to or smaller than the biasing forces F14 and F15, respectively. At this time, the full-circumferential teeth 310d engages with the thread of the lead screw 308, the opposed teeth 311h abuts against the lead screw 308, and tooth skipping is suppressed to the biasing forces F14 and F15. The third engagement state is a state in which the resultant force of the normal forces F12 and F12' in the direction perpendicular to the X8 direction is greater than the biasing force F11, the opposed teeth 311h abuts against the lead screw 308, and the normal forces F12 and F13 are greater than the biasing forces F14 and F15, respectively. At this time, the full circumference tooth portion 310d and the opposing tooth portion 311h gradually run up the inclined surface of the opening angle of the thread of the lead screw 308, and the tooth jump phenomenon occurs in which the tooth jumps over the thread portion.

[0062] Next, the desirable magnitude relationship between the biasing force F11 and the biasing force F14 or biasing force F15 will be described. When the lead screw 308 is rotated to move the lens 302 in the X8 direction, if the biasing force F11 is small, the driving load of the lead screw 308 is small, so it is desirable that the biasing force F11 is as small as possible. Also, in the above-mentioned second engagement state, the biasing forces F14 and F15 are larger, so that tooth jumping is suppressed more. However, if the biasing forces F14 and F15 are made too large, tooth jumping will not occur even for a large external force F10 when the optical device 300 is unintentionally dropped, and there is a risk that the full circumference tooth portion 310d and the opposing tooth portion 311h will be damaged. For this reason, it is desirable to design the spring so that the biasing forces F14 and F15 are between an upper limit value assuming component damage and a lower limit value that prevents tooth jumping up to the desired external force F10. Furthermore, if the biasing force F11 is made larger than the biasing force F14 or F15, the tooth jump suppression effect by the biasing forces F14 and F15 cannot be obtained even when the first engagement state is shifted to the second engagement state. Therefore, in order to increase the tooth jump suppression effect, it is necessary to increase the biasing force F11 in the first engagement state, but this contradicts the desire to reduce the drive load. For this reason, in order to suppress tooth jumping with the biasing forces F14 and F15 and to reduce the drive load by reducing the biasing force F11, it is desirable for the biasing force F11 to be smaller than the biasing forces F14 and F15.

[0063] Next, a configuration in which the opposing teeth portion 311h can be separated from the lead screw 208 with a predetermined gap with high precision in the first engagement state will be described. The balls 315 are assembled in the abutting member 311, and the balls 315 are steel balls, ceramic balls, or the like, and have a higher precision than general resin molded parts, so that the tolerance of the balls 315 can be ignored. In addition, in the X8 direction, the power transmission member 310 and the balls 315 assembled in the abutting member 311 butt against each other, so that the tolerance accumulation between the position of the teeth of the full circumference teeth portion 310d and the position of the opposing teeth portion 311h is reduced. Furthermore, since the abutting member 311 is rotatably engaged with the connecting member 309 around the X10 axis, it can move only in a direction parallel to the X10 axis and is unlikely to tilt with respect to the X10 axis. Therefore, in the X8 direction, the thread portion of the lead screw 308 and the opposing teeth portion 311h can be separated with a predetermined gap with high precision in the X8 direction. Even when tolerance accumulation in the direction orthogonal to the X8 direction is taken into consideration, the opposed teeth portion 311h can be spaced from the lead screw 308 with a predetermined gap with high precision.

[0064] Next, we will explain the effect of incorporating balls 315 in contact member 311. By making balls 315 out of high-strength parts such as metal or ceramic balls, it is possible to obtain effects such as reducing wear and the like caused by the sliding and rotation of power transmission member 310 and reducing the coefficient of friction with power transmission member 310.

[0065] With the above configuration, the resistance force acting between the lead screw 308 and the power transmission member 310 can be reduced by the value of the ratio of the diameter D8 to the diameter D7 shown in FIG. 11(b), or the like. This makes it possible to reduce the loss that occurs when transmitting force from the lead screw 308 to the power transmission member 310. As a result, it is possible to increase the output of the driving force, etc., of the lens holding frame 303 relative to the torque input transmitted from the power source 306 to the lead screw 308, and it is possible to provide an optical device 300 with improved driving efficiency. In addition, since there is no need to use a rolling configuration such as a bearing, it is possible to obtain a compact optical device 300 with low vibration noise and driving noise.

[0066] The disclosure of this embodiment includes the following configuration. (Configuration 1) A holding member movable in the direction of the optical axis of the lens; a lead screw extending in the optical axis direction and rotated by an actuator; a power transmission member including an engagement portion that engages with the lead screw and transmits power in the optical axis direction in response to rotation of the lead screw; a connecting member that includes a support portion that rotatably and slidingly supports the power transmission member and is connected to the holding member; a contact member that contacts the power transmission member; a first biasing means for biasing the contact member from the holding member to the power transmission member in the optical axis direction; a second biasing means for biasing the power transmission member to the lead screw; In the optical axis direction, the power transmission member is biased against the connecting member by the abutment member, The optical device according to claim 1, wherein the connecting member is biased toward the holding member by the power transmission member in the optical axis direction. (Configuration 2) 2. The optical device according to configuration 1, wherein the power transmission member is sandwiched between the abutment member and the connecting member in the optical axis direction. (Configuration 3) The optical device described in configuration 1 or 2, characterized in that the rotational resistance torque acting on the support portion when the power transmission member rotates is smaller than the rotational resistance torque acting on the engagement portion when the lead screw rotates. (Configuration 4) 4. The optical device according to any one of configurations 1 to 3, wherein the connecting member abuts against a surface that contains a rotation shaft of the power transmission member in the optical axis direction. (Configuration 5) 5. The optical device according to any one of configurations 1 to 4, wherein the abutment member abuts against a surface that contains a rotation shaft of the power transmission member in the optical axis direction. (Configuration 6) 6. The optical device according to any one of configurations 1 to 5, wherein the support portion is one of a hole portion and a shaft portion. (Configuration 7) When the diameter of the support portion is D1 and the diameter of the power transmission member is D, 1 <D2 / D1<100 7. The optical device according to any one of configurations 1 to 6, wherein the following condition is satisfied: (Configuration 8) a third biasing means for biasing the contact member against the connecting member in a direction perpendicular to the optical axis; The abutment member is rotatably engaged with the connecting member, the abutment member includes a first abutment portion that abuts against the power transmission member, a second abutment portion that restricts relative rotation between the abutment member and the connecting member in the direction perpendicular to the optical axis, and a third abutment portion that faces the power transmission member across the lead screw in the direction perpendicular to the optical axis, An optical device described in any one of configurations 1 to 7, characterized in that the third abutment portion is separated from the lead screw by a gap smaller than the engagement height of the engagement portion in a direction perpendicular to the optical axis. (Configuration 9) The optical device described in configuration 8, characterized in that in a first state in which a force equal to or greater than a predetermined value is not being applied to the optical device, the power transmission member abuts against the lead screw, and in a second state in which a force equal to or greater than the predetermined value is being applied to the optical device, the power transmission member and the abutment member abut against the lead screw. (Configuration 10) The optical device described in configuration 9, characterized in that in the second state, the force with which the power transmission member and the abutment member are urged by the third urging means to the lead screw is greater than the force with which the power transmission member is urged by the second urging means to the lead screw in the first state. (Configuration 11) 11. The optical device of any one of configurations 8 to 10, wherein the third abutment portion has teeth that are engageable with a thread portion of the lead screw.

[0067] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention. [Explanation of symbols]

[0068] 100 Optical equipment 102 Lens 103 Lens holding frame (holding member) 106 Power source (actuator) 108 Lead Screw 109 Connecting members 109a Sliding support shaft part (support part) 109b Sliding support surface part (support part) 110 Power transmission components 110d Circumferential teeth (engagement part) 111 Contact member 112a compression spring portion (first biasing means) 112b torque spring portion (second biasing means)

Claims

1. A holding member movable in the direction of the optical axis of the lens; a lead screw extending in the optical axis direction and rotated by an actuator; a power transmission member including an engagement portion that engages with the lead screw and transmits power in the optical axis direction in response to rotation of the lead screw; a connecting member that includes a support portion that rotatably and slidingly supports the power transmission member and is connected to the holding member; a contact member that contacts the power transmission member; a first biasing means for biasing the contact member from the holding member to the power transmission member in the optical axis direction; a second biasing means for biasing the power transmission member against the lead screw; In the optical axis direction, the power transmission member is biased against the connecting member by the abutment member, The optical device according to claim 1, wherein the connecting member is biased toward the holding member by the power transmission member in the optical axis direction.

2. 2. The optical device according to claim 1, wherein the power transmission member is sandwiched between the contact member and the connecting member in the optical axis direction.

3. 3. The optical device according to claim 1, wherein a rotational resistance torque acting on the support portion when the power transmission member rotates is smaller than a rotational resistance torque acting on the engagement portion when the lead screw rotates.

4. 3. The optical device according to claim 1, wherein the connecting member abuts against a surface that contains a rotation shaft of the power transmission member in the optical axis direction.

5. 3. The optical device according to claim 1, wherein the contact member contacts a surface that includes a rotation shaft of the power transmission member in the optical axis direction.

6. 3. The optical device according to claim 1, wherein the support portion is one of a hole portion and a shaft portion.

7. When the diameter of the support portion is D1 and the diameter of the power transmission member is D, 1<D2 / D1<100 3. The optical device according to claim 1, wherein the following condition is satisfied:

8. a third biasing means for biasing the contact member against the connecting member in a direction perpendicular to the optical axis, The abutment member is rotatably engaged with the connecting member, the abutment member includes a first abutment portion that abuts against the power transmission member, a second abutment portion that restricts relative rotation with the connecting member in the direction perpendicular to the optical axis, and a third abutment portion that faces the power transmission member across the lead screw in the direction perpendicular to the optical axis, 3. The optical device according to claim 1, wherein the third contact portion is separated from the lead screw by a gap smaller than an engagement height of the engagement portion in the direction perpendicular to the optical axis.

9. The optical device described in claim 8, characterized in that in a first state in which a force greater than or equal to a predetermined value is not applied to the optical device, the power transmission member abuts the lead screw, and in a second state in which a force greater than or equal to the predetermined value is applied to the optical device, the power transmission member and the abutment member abut the lead screw.

10. 10. The optical device according to claim 9, wherein in the second state, the force with which the power transmission member and the abutment member are biased by the third biasing means to bias the lead screw is greater than the force with which the power transmission member is biased by the second biasing means to bias the lead screw in the first state.

11. 9. The optical device according to claim 8, wherein the third contact portion has teeth that are engageable with a thread portion of the lead screw.

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