JP6305000B2 - Lens barrel and imaging device - Google Patents

Description

  The present invention relates to a lens barrel and an imaging apparatus.

  The retractable lens barrel needs to prevent tilting and misalignment of the lens barrel in order to ensure optical performance during photographing. In Patent Document 1, a holding member that holds an optical element is pressed against a guide shaft in one direction by an urging means, so that both the eccentricity in a plane perpendicular to the optical axis and the inclination with respect to the optical axis are detected. A positioning device that ensures accuracy is proposed.

JP 2010-266582 A

  However, Patent Document 1 requires a longer guide support portion of the holding member, which is not suitable for a retractable structure. If the guide support portion is shortened, at least one of eccentricity and inclination positioning accuracy may be reduced. There is.

  An exemplary object of the present invention is to provide a retractable lens barrel and an imaging apparatus capable of ensuring the adjustment accuracy of eccentricity and inclination of two guide portions that guide a holding member of an optical element. To do.

The lens barrel of the present invention is a retractable lens barrel, is configured to be movable in the optical axis direction of the optical element, and holds the optical element. A first guide for guiding; a second guide configured to be movable in the optical axis direction of the optical element with respect to the first guide; a fixing member including the first guide; A rectilinear member that includes a second guide portion and is movable in the optical axis direction with respect to the fixed member; The optical axis of the second guide portion with respect to the first guide portion by pressing the linearly moving member against the fixed member at a plurality of locations in a plane orthogonal to the optical axis, and an eccentricity adjusting means for adjusting the core It has a tilt adjusting means for adjusting the downward tilt, and the holding member A first guided portion which is guided by the first guide portion, and a second guided portion to be guided by the second guide section, further comprising a, in the transition to state unwinding from the collapsed state, After the second guide unit is moved closer to the subject side than the first guide unit, the tilt adjustment by the tilt adjustment unit is completed after the eccentricity adjustment by the eccentricity adjustment unit , and the first guide unit is the light The first guide shaft extends in the axial direction, and the second guide portion is a second guide shaft extending in the optical axis direction .

  According to the present invention, it is possible to provide a retractable lens barrel and an imaging apparatus capable of ensuring the adjustment accuracy of the eccentricity and inclination of the two guide portions that guide the holding member of the optical element. The predetermined optical performance of the element can be ensured.

It is a fragmentary sectional view of the lens barrel of this embodiment in the extended state. FIG. 2 is a partially transparent front view of the lens barrel shown in FIG. 1. It is a fragmentary sectional view of the lens barrel shown in FIG. FIG. 2 is a development view of a fixed cylinder and a cam cylinder shown in FIG. 1. It is a schematic sectional drawing which shows the rectilinear key of the rectilinear cylinder shown in FIG. It is a figure which shows the structure of the wedge member shown in FIG. It is a schematic sectional drawing explaining the retracting operation | movement of the lens-barrel shown in FIG. FIG. 2 is a development view of a fixed barrel and a cam barrel when the lens barrel shown in FIG. 1 is retracted and extended. It is a flowchart which shows the retracting operation | movement of the lens-barrel shown in FIG. It is a flowchart which shows extending operation | movement of the lens-barrel shown in FIG. It is a figure for demonstrating the biasing order in this embodiment. It is a figure for demonstrating the biasing order different from this embodiment. It is a graph for demonstrating the effect of FIG. 11 and FIG.

  Hereinafter, the lens barrel of this embodiment will be described. The lens barrel houses a photographing optical system that forms an optical image of a subject, and is fixed to an imaging device such as a digital video camera. The imaging apparatus includes an imaging element that photoelectrically converts an optical image formed by the imaging optical system.

  The lens barrel includes a fixed barrel 1, a cam ring 2, a rectilinear barrel 3, a lens frame 4, a lens 5, a first main bar 6b, a second main bar 6a, a sub bar 6c, a feed screw 7, a motor 8, and other members. Have. OA indicated by the alternate long and short dash line is the optical axis of the lens 5.

  FIG. 1 is a schematic cross-sectional view including the optical axis of the photographing optical system of the lens frame 4 of the lens barrel, and shows a state in which the rectilinear cylinder 3 is extended (projected). When the straight cylinder 3 is extended, it is possible to shoot with a high holding accuracy of the lens 5, and this state may be referred to as a “shooting state” hereinafter. On the other hand, the state in which the rectilinear cylinder 3 is retracted (retracted) is a retracted state, which is a non-photographing state or a state where photographing that does not require the holding accuracy of the lens 5 is possible. The left side of FIG. 1 is the subject side, and the right side is the image plane side. This is the same in other sectional views unless otherwise specified. FIG. 1A is a diagram illustrating a state in which the lens frame 4 is extended (a state in which the lens frame 4 is moved), and FIG. 1B is a state in which the lens frame 4 is retracted (a state in which the lens frame 4 is moved to the image side). FIG. Thus, the lens barrel of the present embodiment can be retracted, and the portability is improved by downsizing.

  The fixed cylinder 1 is a fixed member, and a cam ring 2 is provided on the fixed cylinder 1 so as to be rotatable around the optical axis. FIG. 3A is a partial cross-sectional view including the optical axis of the lens barrel in the photographing state. The fixed cylinder 1 has a first main bar (first guide portion, first guide shaft) 6b and a rectilinear groove 11 extending in the optical axis direction.

  The first main bar 6 b has a cylindrical shape made of stainless steel or the like, extends in the optical axis direction, and both ends thereof are held by the fixed cylinder 1. In this embodiment, the guide shaft is used as the guide portion, but a key structure (key and key groove) may be used instead of the shaft.

  As will be described later, in this embodiment, three rectilinear grooves 11 are provided, and a rectilinear key (straight section) 32 is fitted in each, and each rectilinear key 32 moves along the corresponding rectilinear groove 11. One rectilinear key 32 functions as an eccentricity adjusting means, and may be distinguished from the other two rectilinear keys (second rectilinear portion) 32b, 32c as a rectilinear key (first rectilinear portion) 32a, as will be described later. is there. The rectilinear groove 11 into which the rectilinear key 32a is fitted may be distinguished as the first groove and the rectilinear groove 11 into which the rectilinear keys 32b and 32c are fitted as a second groove.

  The cam ring 2 has a substantially cylindrical shape, is provided with a cam groove 21, and rotates by receiving a driving force from a motor (not shown) or the like.

  The rectilinear cylinder 3 has a substantially cylindrical shape and is disposed inside the cam ring 2. The rectilinear cylinder 3 is a rectilinear member, and includes a second main bar 6a as a second guide portion (second guide shaft), a sub bar 6c, and a cam follower 31 that moves along the cam groove. When the cam ring 2 rotates with respect to the fixed cylinder 1, the cam follower 31 moves along the cam groove 21, and the rectilinear cylinder 3 moves with respect to the fixed cylinder 1 in the optical axis direction of the lens 5.

  The lens frame 4 is a holding member that holds the lens 5 that is a part of the photographing optical system, and can move in the optical axis direction to change the imaging state of the light beam. The lens 5 is an example of an optical element, but the optical element is not limited to a lens.

  The lens frame 4 is a holding member that holds the lens 5 that is a part of the photographing optical system, and can move in the optical axis direction to change the imaging state of the light beam. The lens 5 is an example of an optical element, but the optical element is not limited to a lens.

  The lens frame 4 has fitting portions 9a and 9b each having a substantially cylindrical hole shape, and is fitted to the second main bar 6a and the first main bar 6b, respectively. The second main bar 6 a and the first main bar 6 b constitute a guide unit that guides the lens frame 4. The fitting portions 9a and 9b have a backlash necessary for sliding with respect to the second main bar 6a and the first main bar 6b and are fitted. For this reason, the lens frame 4 may be tilted relative to the optical axis.

  The fitting portions 9a and 9b are separated by a distance L, and the fitting portion 9a that is the first guided portion is disposed closer to the subject than the fitting portion 9b that is the second guided portion. As the distance L of the lens frame 4 increases, the inclination relative to the optical axis tends to decrease.

  FIG. 2 is a partially transparent front view of the lens barrel as seen from the subject side. As shown in FIG. 2, the fitting portion 9c has a U-shape when viewed from the front, and is engaged with the sub bar 6c. The fitting portion 9c suppresses inclination due to rotation around the axis connecting the lens frame 4 to the fitting portions 9a and 9b. The lens frame 4 also tilts when the relative position between the second main bar 6a and the first main bar 6b changes. That is, in order to reduce the inclination of the lens frame 4, it is important to hold the second main bar 6a and the first main bar 6b so that the relative position between them does not change.

  Each of the second main bar 6a and the sub bar 6c has a cylindrical shape made of stainless steel or the like, extends in a direction parallel to the optical axis, and both ends thereof are held by the rectilinear cylinder 3. The fitting portion 9b as the first guided portion and the fitting portions 9a and 9c as the second guided portion are respectively along the optical axis by the first main bar 6b, the second main bar 6a, and the sub bar 6c. Guided. In FIG. 2, the second main bar 6a is disposed at a position shifted from the radial direction connecting the optical axis and the center of the first main bar 6b, thereby preventing an increase in the radial direction.

  Conventionally, a lens barrel having a single main shaft (main bar) and a sub shaft (sub bar) as a guide shaft for guiding the movement of the holding member of the optical element has not been retracted. In the present embodiment, the main shaft is divided into two parts, a first main bar 6a and a second main bar 6b, so that the main shaft can be retracted and the entire length is shortened in the optical axis direction of the photographing optical system at the time of non-photographing, thereby improving portability. It is increasing.

  However, if one main shaft is divided into two and configured to be relatively movable, a slight gap (backlash) is formed between the two, and if the lens frame 4 moves as it is, eccentricity or tilting will occur. Occurs, and the optical performance of the lens 5 cannot be ensured. Therefore, a lock means for fixing (locking) and releasing (unlocking) the second main bar 6a with respect to the first main bar 6a is provided, and the lens frame 4 is extended after being locked by the lock means, so that the optical performance is improved. Is secured.

  The lock means has an eccentricity adjustment means and an inclination adjustment means. The eccentricity adjusting means adjusts the eccentricity of the second main bar 6a with respect to the first main bar 6b in a plane orthogonal to the optical axis of the lens 5. The tilt adjusting means presses the straight cylinder 3 to the fixed cylinder 1 at a plurality of locations (at least two locations, not necessarily in the same plane) in a plane orthogonal to the optical axis. 2 The inclination of the main bar 6a in the optical axis direction is adjusted.

  In Patent Document 1, the eccentricity and the inclination are adjusted by pressing the lens frame on the guide bar at one position, and the lens frame is locked on the guide bar after moving on the guide bar. And since the guide bar is fixed, it cannot retract.

  On the other hand, the inclination adjusting means of this embodiment adjusts the inclination by pressing the rectilinear cylinder 3 against the fixed cylinder 1 in the plane orthogonal to the optical axis, and a component that is long in the optical axis direction is unnecessary. Can be retracted. Here, the rectilinear cylinder 3 is brought into surface contact with the fixed cylinder 1, but the present embodiment is intended to include spherical pressing (point contact) and the like.

  In the present embodiment, when the eccentricity adjusting means acts, a part of the inclination adjusting means acts simultaneously. Further, the power point position of the tilt adjusting means that acts first is closer to the power point position of the eccentricity adjusting means than the power point position of the tilt adjusting means that acts later. In view of this, the inclination adjustment by the inclination adjustment means is completed after the eccentricity adjustment by the eccentricity adjustment means. Thus, the lens frame 4 is moved in a state where the eccentricity adjustment accuracy and the inclination adjustment accuracy are ensured, and an optical image is formed by the lens 5 to prevent image shake. Further, by using the guide shaft, it is possible to achieve quieter noise than a mechanism that moves the lens only by the cam.

  Next, a moving unit that moves the lens frame 4 back and forth will be described. The motor 8 is fixed to the fixed cylinder 1 and the feed screw 7 is fixed to the output shaft of the motor 8. The rack 41 is attached to the lens frame 4, is rotatable about an axis parallel to the optical axis, and is held so as not to move relative to the lens frame 4 in the optical axis direction. The rack 41 engages with the feed screw 7 and converts the rotation of the feed screw 7 into advance and retreat in the optical axis direction. As a result, the lens frame 4 can be moved back and forth in the optical axis direction by the rotation of the motor 8.

  In FIG. 1A, the lens frame 4 is located closer to the subject. For example, when the lens 5 is a zoom optical element, it can be set to the wide angle side. With the rotation of the motor 8, as shown in FIG. 1 (b), it can move to the far side from the subject and enter the telephoto state. For example, when a stepping motor is used as the motor 8, the number of pulses can be counted, and thus the movement amount of the lens frame 4 can be accurately grasped. It is also possible to calibrate the absolute position of the lens frame 4 with respect to the fixed cylinder 1 by installing a photo interrupter 15 as position detecting means in the fixed cylinder 1 and installing a light shielding wall 45 for position detection in the lens frame 4. It is.

  As shown in FIG. 3A, the fixed cylinder 1 has a bayonet portion 16 for preventing the cam ring 2 from coming off in the optical axis direction. The cam ring 2 is installed so as to be rotatable within a predetermined angle range with respect to the fixed cylinder 1 using a stopper (not shown) or the like.

  A cam groove 21 is disposed on the inner periphery of the cam ring 2, and the cam groove 21 is engaged with a cam follower 31. The cam follower 31 has a convex shape on the outer periphery of the rectilinear cylinder 3. The rectilinear cylinder 3 has a rectilinear key 32 and is engaged with the rectilinear groove 11 of the fixed cylinder 1 to be restricted from rotating around the optical axis. As a result, when the cam ring 2 rotates, the rectilinear cylinder 3 moves forward and backward in the optical axis direction according to the locus of the cam groove 21.

  In the photographing state, the leaf spring 23 that rotates and moves around the optical axis in conjunction with the cam ring 2 bends, and the wedge member 36 as a pressing means is lighted on the plane perpendicular to the optical axis from the vicinity of the inner peripheral surface of the cam ring 2. It is urged by the input urging force Fi toward the axis center. The movement of the leaf spring 23 is not limited to rotation. The wedge member 36 constitutes an eccentricity adjusting means and an inclination adjusting means.

The input urging force Fi urges the rectilinear cylinder 3 and the fixed cylinder 1 through the third abutting surface 35 installed on the rectilinear cylinder 3 and the fourth abutting surface 17 installed on the fixed cylinder 1, respectively. The third contact surface 35 receives the lens barrel urging force Fa as a plane substantially orthogonal to the optical axis. The fourth abutting surface 17 is set so that the surface interval becomes narrower toward the third abutting surface 35 in the direction in which the wedge member 36 is urged by the leaf spring 23, and receives Fb. Therefore, the wedge member 36 biased by the leaf spring 23 has the effect of increasing the wedge. That is, the force that biases the third contact surface 35 and the fourth contact surface 17 can be amplified from the input biasing force Fi by the leaf spring 23. For example, the barrel urging force Fa of the third abutting surface 35 is expressed as follows:
Fa = Fi / tan (θw)
If θw <45 °, the relationship is Fa> Fi and the force is amplified. Details of the wedge member 36 will be described later.

  In FIG. 3, the rectilinear cylinder 3 urged by the third abutment surface 35 has the rectilinear key 32 abutted against the second abutment surface 12. The second contact surface 12 is a surface that is connected to the rectilinear groove 11 and is orthogonal to the optical axis. Of the second abutment surfaces 12, the second abutment surface 12 that contacts the rectilinear key 32a is distinguished as the first surface, and the second abutment surface 12 that contacts the rectilinear keys 32b and c is distinguished as the second surface. In the present embodiment, the second contact surface 12 is an end surface on the subject side, but may be a surface of a block fixed to the rectilinear groove 11.

  Three second contact surfaces 12 are arranged around the optical axis. That is, the second abutment surface 12 is compared with FIG. 1 and FIG. 3, near the image plane side end of the second main bar 6 a and the subject side end of the first main bar 6 b when viewed on the optical axis. It is arranged near the part. When the rectilinear key 32 is abutted against the second contact surface 12, the inclination of the rectilinear cylinder 3 with respect to the fixed cylinder 1 can be adjusted. Since the fixed cylinder 1 has the first main bar 6b and the rectilinear cylinder 3 has the second main bar 6a, the relative inclination of the second main bar 6a and the first main bar 6b is also adjusted and kept parallel. Can do. As a result, the holding accuracy of the lens frame 4 in the photographing state can be improved.

  FIG. 4 is a developed view of the circumferential direction of the fixed cylinder 1 and the cam ring 2.

  The fixed cylinder 1 has three rectilinear grooves 11 and is arranged at approximately 120 ° equally. Similarly, three rectilinear keys 32 (in order to distinguish these, 32a to 32c are inserted) in each rectilinear groove 11. As a result, the rectilinear cylinder 3 moves forward and backward with respect to the fixed cylinder 1 while keeping the eccentricity with respect to the optical axis within the range of play. Further, the straight key 32 is brought into contact with the second contact surface 12 by the action of the leaf spring 23 (in FIG. 4, shown as 23a to 23c in order to distinguish them) as the inclination adjusting means, thereby adjusting the inclination. ing.

  The cam grooves 21 are arranged at approximately 120 ° equally. In the present embodiment, the cam follower 31 is provided at the same angular position as the rectilinear key 32, but may be provided at a different angular position. In order to avoid interference between the cam groove 21 and the cam follower 31, the cam groove 21 has an escape portion 21e. In other words, the width of the cam groove 21 at the extended position of the rectilinear cylinder 3 is wider than the width of the cam groove 21 at the retracted position of the rectilinear cylinder. In the locus of the cam groove 21, the position accuracy is improved by setting the backlash of the cam groove 21 and the cam follower 31 to be small while the straight cylinder 3 is being fed. On the other hand, in the shooting state, the relative positional accuracy between the straight cylinder 3 and the fixed cylinder 1 is important, and it is necessary to avoid the interference between the cam groove 21 and the cam follower 31. However, if the cam groove 21 and the cam follower 31 have a large backlash, the escape portion 21e may not be installed.

  Three leaf springs 23 that rotate in conjunction with the cam ring 2 are also provided at substantially the same angular position as the rectilinear key 32. In the present embodiment, the leaf spring (first urging member) 23a and the leaf springs (second urging member) 23b, 23c have different widths in the circumferential direction of the cam ring 2, and the circumferential direction of the leaf spring 23a. Is wider than the widths d2 and d3 of the leaf springs 23b and 23c (d1> d2≈d3). On the other hand, the three wedge members 36 have the same shape. The leaf spring 23a is an eccentricity adjusting means and is also a part of the inclination adjusting means. The leaf spring 23a serves as both the eccentricity adjusting means and the inclination adjusting means, but the inclination adjustment is completed when the adjustment by the leaf springs 23b and c is completed. Thereby, when shifting from the non-photographing state to the photographing state, the leaf spring 23a starts to bias the wedge member 36 before the leaf springs 23b and 23c. The order of energization will be described later.

  FIG. 3A corresponds to a cross section at the position of the leaf spring 23b or 23c. FIG. 3B shows the cross section at the position of the leaf spring 23a. In FIG.3 (b), the 3rd contact surface 35 is provided in the component force block 37 which has a right-angled triangular cross section. The component force block 37 is in contact with the rectilinear cylinder 3 at the fifth contact surface 38 on the inclined surface. The component force block 37 is disposed in the rectilinear groove 11 and has a third contact surface 35, and divides the force received by the third contact surface into a force perpendicular to the optical axis and a force in the optical axis direction. FIG. 3 shows a first position where the wedge member 36 is urged by the leaf spring 23 and contacts the fixed cylinder 1.

  For this reason, the urging force Fi by the leaf spring 23a has components of a force Fa parallel to the optical axis and a force Fc perpendicular to the optical axis and away from the optical axis. The force Fc acts to decenter the rectilinear cylinder 3 in the direction perpendicular to the optical axis with respect to the fixed cylinder 1.

  FIG. 5 is a view of a plane perpendicular to the optical axis, taken from the subject side, from which the relevant portion of the rectilinear groove 11 and the rectilinear key 32 is extracted from the fixed cylinder 1 and the rectilinear cylinder 3. As shown in FIG. 5, when the force Fc is applied at the position of the rectilinear key 32a, the rectilinear key 32b and the rectilinear key 32c are pressed against the walls (side walls) 11b and 11c, which are the first contact surfaces, respectively ( I'm going to lie down. The eccentricity adjustment is performed by moving one member, but may be performed by moving a plurality of members.

  In this state, if the walls 11b and 11c are processed so that the rectilinear cylinder 3 comes to the center without being eccentric with respect to the fixed cylinder 1, the fixed cylinder 1 and the rectilinear cylinder 3 are affected by the force Fc. It is possible to improve the positional accuracy by adjusting the relative eccentricity. As a result, it leads to improving the space | interval precision of the 1st main bar 6b and the 2nd main bar 6a. That is, the eccentric position is set by bringing the linearly-moving keys 32b and 32c into contact with the walls 11b and 11c as the first contact surfaces by the action of the leaf spring (first urging member) 23a as the eccentricity adjusting means. It is adjusted.

  As described above, the first main bar 6b and the second main bar 6a improve the positional accuracy of both the eccentric direction accuracy orthogonal to the optical axis and the relative parallel accuracy, and high optical accuracy even when the lens frame 4 moves. Can be realized.

  Next, details of the wedge member 36 will be described with reference to FIG.

  FIG. 6A is a perspective view of the wedge member 36. Reference numeral 36 a denotes a protrusion that is urged by the leaf spring 23. Reference numeral 36 b denotes a curved surface that comes into contact with the rectilinear cylinder 3 at the third contact surface 35. 36 c is a curved surface that contacts the fixed cylinder 1 at the fourth contact surface 17. Reference numeral 36d denotes a rotation shaft, and the wedge member 36 can rotate around the rectilinear cylinder 3 via the rotation shaft 36d. Instead of providing the rotating shaft 36d in the wedge member 36, a shaft may be provided in the linear cylinder 3 and a through hole through which the shaft passes may be provided in the wedge member 36. A torsion spring 37 is attached to the rotation shaft 36d. The torsion spring 37 functions as a return means for applying a force for returning from the first position shown in FIG. 3 to the second position shown in FIG. 7, but the return means is not limited to the torsion spring 37.

  FIG. 6B is a plan view of the rectilinear cylinder 3 and the wedge member 36. The rotary shaft 36d is loosely constrained so that it cannot move greatly in the optical axis direction with a backlash provided by the rough guide 39 provided in the rectilinear cylinder 3. Thereby, the wedge member 36 can advance and retreat in the optical axis direction together with the rectilinear cylinder 3.

  FIG. 6C is a side view of the rectilinear cylinder 3 and the wedge member 36. The wedge member 36 is acted on by a torsion spring 37 to rotate around the rotation shaft 36d in the direction of the arrow. This rotating force is set to be sufficiently smaller than the urging force Fi by the leaf spring 23. In the photographing state, the wedge member 36 biased by the leaf spring 23 is pressed against the inner peripheral side of the lens barrel. On the contrary, when the urging by the leaf spring 23 is released, the wedge member 36 is rotated to the outer peripheral side by the rotational force of the torsion spring 37.

  The relationship between the 4th contact surface 17 and the 2nd contact surface 12 is demonstrated. In the photographing state, the fourth contact surface 17 is in contact with the wedge member 36. As shown in FIG. 3, the fourth contact surface 17 has a shape in which the rectilinear groove 11 is partially cut away. As shown in FIG. 6B, the region sandwiched between the walls of the rectilinear groove 11 is defined as A. The fourth contact surface 17 is arranged outside the area A in a divided state. Thereby, when the rectilinear cylinder 3 moves forward and backward, the rectilinear key 32 within the range of the area A can pass without interference. On the other hand, as shown in FIG. 6B, the second abutting surface 12 is a surface where the rectilinear key 32 abuts on the fixed cylinder 1, and is therefore disposed in a region sandwiched between the walls of the rectilinear groove 11. Yes. Therefore, the fourth contact surface 17 and the second contact surface 12 are arranged without overlapping when viewed from the optical axis direction.

  Next, a retracting operation when shifting from the shooting state to the non-shooting state will be described. FIG. 9A is a flowchart when shifting from the shooting state to the non-shooting state, and “S” represents a step. Each step can be embodied as a program for causing a control means (not shown) configured by a microcomputer or the like to realize the function of each step. This is also true for other flowcharts.

  First, in S101, the lens frame 4 is retracted. When the rectilinear cylinder 3 moves to realize the collapse, the rectilinear cylinder 3 moves as shown in FIG. 1B because the movement of the rectilinear cylinder 3 is obstructed if the lens frame 4 is close to the subject. The lens frame 4 is moved to the image plane side before. When the lens frame 4 moves, since the two main bars are locked by the locking means, the lens frame 4 can move smoothly.

  Next, in S102, the rotation of the cam ring 2 is started, and in S103, the urging of the wedge member 36 is released in conjunction with the rotation of the cam ring 2. The details of releasing the bias to the wedge member 36 will be described later.

  FIG. 8 is a development view of the cam ring 2. FIG. 8A shows the photographing state, and the retracting operation sequentially changes from the state shown in FIGS. 8A to 8D. When the urging of the wedge member 36 is released in S103, the state shown in FIG. The cam follower 31 does not move in the optical axis direction. The wedge member 36 is rotated by the torsion spring 37 around the rotation shaft 36d to the outer peripheral side of the lens barrel as indicated by an arrow in FIG. As a result, the state shown in FIG. The protrusion 36 a of the wedge member 36 enters the space of the relief groove 22 of the cam ring 2. As a result, the cam ring 2 and the wedge member 36 overlap when viewed from the optical axis direction. FIG. 7 shows a second position in which the wedge member 36 is not biased by the leaf spring 23 and is separated from the fixed cylinder 1. The wedge member 36 is configured to be rotatable between a first position shown in FIG. 3 and a second position shown in FIG. The movement is not limited to rotation.

  In S104, the cam ring 2 further rotates, the cam follower 31 moves along the cam groove 21, and the rectilinear cylinder 3 moves toward the image plane side.

  In S105, the rectilinear cylinder 3 moves to a predetermined position and the collapsing is completed, and the state shown in FIG. In order to determine that the rectilinear cylinder 3 has moved to a predetermined position, for example, it is possible to count the number of rotations of a motor that uses the cam ring 2 as a rotation drive source. FIG. 7B shows this collapsed state.

  In S106, the rotation of the cam ring 2 is stopped, and the retracting operation is completed.

  The operation of releasing the bias to the wedge member 36 in S103 will be described in detail with reference to FIG.

  In S111, the urging of two of the three wedge members 36 is released. In S111, the state shown in FIG. 8B is reached, and the leaf springs (second urging members) 23b and 23c are changed to a state in which the wedge member 36 is not urged. However, the leaf spring 23a still biases the wedge member 36. As described above, the inclination of the rectilinear cylinder 3 with respect to the fixed cylinder 1 is adjusted by urging the wedge member 36 at three locations in the optical axis direction. That is, the adjustment of the inclination is released by releasing the biasing of the wedge member 36 at two locations.

  In S112, the state shown in FIG. The leaf spring 23a urges the wedge member 36 as described above to adjust the eccentricity of the fixed cylinder 1 and the rectilinear cylinder 3. That is, in the state of FIG. 8C in which the bias of the leaf spring 23a is released, the eccentricity adjustment is released. Thus, the bias of the wedge member 36 is released.

  As described above, the transition from the extended state to the retracted state is completed, and the total length of the lens barrel in the optical axis direction is shortened.

  Conversely, the flow of transition from the retracted state to the extended state will be described. FIG. 10A is a flowchart of the operation from the retracted state to the extended state.

  In S201, the rotation of the cam ring 2 is started. At this stage, the cam groove 21 and the cam follower 31 are in the relationship shown in FIG. In S202, in response to the rotation of the cam ring 2, the rectilinear cylinder 3 starts to be extended. In S203, the cam groove 21 and the cam follower 31 are in the relationship shown in FIG. 8C, and the straight cylinder 3 is extended to the most object side. In S <b> 204, the urging force of the wedge member 36 acts as will be described later, whereby the eccentricity and inclination of the rectilinear cylinder 3 are adjusted with respect to the fixed cylinder 1. In S205, the extended state shown in FIG. 8A is entered, and the rotation of the cam ring 2 is stopped.

  Hereinafter, the urging to the wedge member 36 will be described with reference to FIG.

  In S211, only the leaf spring 23a that adjusts the relative position in the plane orthogonal to the optical axis of the second main bar 6a and the sub bar 6c with respect to the first main bar 6b is attached to the first main bar 6b. It is fast. In this state, the wedge member 36 is urged, and the urging forces Fa and Fc are generated as shown in FIG. In FIG. 5, only the rectilinear key 32 a portion of the rectilinear cylinder 3 is pressed against the second abutting surface 12 with respect to the fixed cylinder 1. The second abutting surface 12 is not pressed against the linearly-moving keys 32b and 32c without generating an urging force. Therefore, the inclination of the rectilinear cylinder 3 with respect to the fixed cylinder 1 is not adjusted. On the other hand, the eccentricity is adjusted by pressing the rectilinear keys 32b and 32c against the walls 11b and 11c by Fc.

  In S212, as shown in FIG. 8A, all of the leaf springs 23a, 23b, and 23c, which are inclination adjusting means for adjusting the inclination of the second main bar 6a and the sub bar 6c with respect to the first main bar 6b with respect to the optical axis direction. Is in an energized state. That is, the rectilinear keys 32 a, 32 b, and 32 c are pressed against the second abutting surface 12 at three locations, and the inclination of the rectilinear cylinder 3 is adjusted with respect to the fixed cylinder 1. Thus, after the second main bar 6a and the sub bar 6c, which are the second guide portions, are extended to the subject side, the leaf spring 23a serving as the eccentricity adjusting means and the inclination adjusting means acts, and thereafter the leaf springs 23b and 23c. Completes the tilt adjustment.

  FIG. 11 is a diagram illustrating a state of the lens barrel at the stage where S211 in FIG. 10B is completed.

  FIG. 11A is a cross-sectional view of a straight key. By the straight keys 32b, 32c being pressed against the walls 11b, 11c without any backlash, the eccentricity in the plane perpendicular to the optical axis of the straight tube 3 relative to the fixed tube 1 is adjusted.

  FIG.11 (b) shows BB sectional drawing in Fig.11 (a). Although the rectilinear key 32a is pressed against the second abutting surface 12 without backlash, the rectilinear keys 32b and 32c are not pressed against the second abutting surface 12 and play occurs. In FIG. 11B, the rectilinear key 32c is not shown, but is in the same state as the rectilinear key 32b. In other words, the inclination with respect to the optical axis of the rectilinear cylinder 3 is generated with respect to the fixed cylinder 1.

  Next, in order to adjust the generated inclination, the leaf springs 23 b and 23 c (not shown in FIG. 11) act on the wedge member 36, and the rectilinear keys 32 b and 32 c are pressed against the second contact surface 12. This operation can be adjusted relatively easily by directly energizing the vicinity of the linearly-moving keys 32b and 32c by the wedge member.

  Here, in FIG.10 (b), implementing S211 after S212 is considered. FIG. 12 is a diagram illustrating a state in which S212 is completed without performing S211 in FIG.

  FIG. 12A is a cross-sectional view of a straight key. The straight keys 32b and 32c are not pressed against the walls 11b and 11c and have backlash, and an eccentricity is generated in a plane perpendicular to the optical axis of the straight tube 3 with respect to the fixed tube 1.

  FIG.12 (b) shows CC sectional drawing in Fig.12 (a). The rectilinear keys 32b and 32c are pressed against the second contact surface 12 without backlash. In FIG. 12B, although the straight key 32c is not shown, it is in the same state as the straight key 32b. Since the straight key 32a is pressed at the two points of the straight keys 32b and 32c, there is almost no backlash at the straight key 32a and the second contact surface 12. That is, the inclination with respect to the optical axis of the rectilinear cylinder 3 is adjusted with respect to the fixed cylinder 1.

  In this next stage, the eccentricity is adjusted, but a leaf spring 23a (not shown in FIG. 12) acts on the wedge member 36 in FIG. 12, and in the plane perpendicular to the optical axis via the component force block 37. Try to adjust the eccentricity. However, the two points of the straight keys 32 b and 32 c are already pressed against the second contact surface 12. The pressing force generated in the component force block 37 installed in the vicinity of the straight key 32a exerts a force that causes the eccentricity adjustment, but the two frictional forces generated in the vicinity of the straight key 32b and 32c inhibit the eccentricity adjustment. . That is, it is difficult to perform the tilt adjustment first and then perform the eccentricity adjustment.

  FIG. 13 is a graph showing the remaining state of adjustment in the order of eccentricity adjustment and inclination adjustment. The horizontal axis represents the passage of time, and the execution timing of eccentricity adjustment and inclination adjustment is indicated by a vertical broken line. If the eccentricity adjustment is performed first as in the present embodiment, as shown in FIG. 13A, after the inclination adjustment is performed, the deviation amount for both the eccentricity and the inclination can be made substantially zero. On the other hand, when the tilt adjustment is performed first, as shown in FIG. 13B, after the eccentricity adjustment is performed, the eccentricity adjustment is hindered by the frictional force and the remaining eccentricity occurs as described above.

  This problem is caused by reducing the frictional force between the second contact surface 12 and the straight key 32 or by making the elastic force of the leaf spring 23a more than twice the elastic force of the leaf springs 23b and c. Can also be solved. However, in this case, it is necessary to create a surface treatment for reducing the frictional force between the second contact surface 12 and the straight key 32 and the leaf spring 23a separately from the leaf springs 23b and c, which makes the manufacturing complicated. It becomes cost rise. For this reason, the structure of this embodiment is preferable.

  As described above, the accuracy of the eccentricity adjustment and the inclination adjustment can be improved by applying the eccentricity adjustment first and then performing the inclination adjustment by applying the inclination adjustment first and then performing the inclination adjustment. Both can be enhanced. In other words, it is possible to maintain the accuracy of relative eccentricity and inclination of the plurality of guide portions in the photographing state of the lens barrel having the guide portions that guide the plurality of lenses relatively moving in the optical axis direction. Become.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to this embodiment, A various deformation | transformation and change are possible within the range of the summary.

  The lens barrel of the present invention can be applied to a lens-integrated camera (digital video camera).

4 ... lens frame (holding member), 5 ... lens (optical element), 6b ... first main bar (first guide portion), 6a ... second main bar (second guide portion), 23a ... leaf spring (eccentric) Adjusting means, tilt adjusting means), 23b, 23c... Leaf spring (tilt adjusting means), OA.

Claims (12)

A retractable lens barrel,
An optical element;
A holding member configured to be movable in the optical axis direction of the optical element, and holding the optical element;
A first guide for guiding the holding member; a second guide configured to be movable in the optical axis direction of the optical element with respect to the first guide;
A fixing member provided with the first guide part;
A rectilinear member comprising the second guide part and movable in the optical axis direction with respect to the fixed member;
An eccentricity adjusting means for adjusting the eccentricity of the second guide part with respect to the first guide part in a plane orthogonal to the optical axis of the optical element;
An inclination adjusting means for adjusting an inclination of the second guide portion in the optical axis direction with respect to the first guide portion by pressing the rectilinear member against the fixing member at a plurality of positions in a plane orthogonal to the optical axis; ,
Have
The holding member further includes a first guided portion guided by the first guiding portion, and a second guided portion guided by the second guiding portion,
In the transition from the retracted state to the extended state, after the second guide portion is moved closer to the subject side than the first guide portion, the tilt adjustment by the tilt adjustment unit is performed after the eccentricity adjustment by the eccentricity adjustment unit. complete,
The lens barrel, wherein the first guide portion is a first guide shaft extending in the optical axis direction, and the second guide portion is a second guide shaft extending in the optical axis direction .   The lens barrel according to claim 1, wherein a part of the tilt adjusting unit simultaneously operates when the eccentricity adjusting unit operates.   3. The lens mirror according to claim 1, wherein a power point position of the tilt adjusting unit that operates first is closer to a power point position of the eccentricity adjusting unit than a power point position of the tilt adjusting unit that operates later. Tube. In a plane perpendicular to the optical axis, any of the claims 1 to 3, characterized in that it is arranged at a position shifted in the second guide portion in a direction connecting the center of the first guide portion and the optical axis the lens barrel according to any one of claims. A cam ring provided on the fixed member so as to be rotatable around the optical axis of the optical element;
The rectilinear member further includes a cam follower that moves along the cam;
2. When the cam ring rotates with respect to the fixed member, the cam follower moves along the cam, and the rectilinear member moves with respect to the fixed member in the optical axis direction. 4. The lens barrel according to claim 1. 6. The lens barrel according to claim 5 , wherein a width of the cam at the extended position of the rectilinear member is wider than a width of the cam at the retracted position of the rectilinear member. The fixing member further includes a first groove and a second groove extending in the optical axis direction,
The rectilinear member further includes a first rectilinear portion that moves along the first groove of the fixing member, and a second rectilinear portion that moves along the second groove,
The eccentricity adjusting means applies a force having a component in a direction away from the optical axis to a surface of the first rectilinear portion perpendicular to the optical axis, thereby moving the second rectilinear portion to the side wall of the second groove. The lens barrel according to any one of claims 1 to 6 , wherein the lens barrel is moved. The fixing member further includes a first groove and a second groove extending in the optical axis direction,
The rectilinear member further includes a first rectilinear portion that moves along the first groove of the fixing member, and a second rectilinear portion that moves along the second groove,
The inclination adjusting means is connected to the first rectilinear portion and the first groove, is brought into contact with a first surface orthogonal to the optical axis, is connected to the second rectilinear portion and the second groove, and The lens barrel according to any one of claims 1 to 7, wherein a second surface perpendicular to the axis is brought into contact with the lens barrel. The inclination adjusting means is connected to the first rectilinear portion and the first groove, is brought into contact with a first surface orthogonal to the optical axis, is connected to the second rectilinear portion and the second groove, and Contacting a second surface perpendicular to the axis;
The lens barrel is
A first urging member that urges the first rectilinear part to urge the first rectilinear part against the first surface in a direction away from the optical axis;
A second urging member that urges the second rectilinear portion to press against the second surface;
A cam ring provided with a cam, the first urging member, and the second urging member;
Further comprising
The rectilinear member further includes a cam follower that moves along the cam;
The first urging member functions as the eccentricity adjusting means and the inclination adjusting means, the second urging member functions as the inclination adjusting means,
As the cam ring rotates, the first urging member moves away from the optical axis to the first rectilinear portion before the second urging member presses the second rectilinear portion against the second surface. Biasing is started so as to press the direction and the first rectilinear portion against the first surface, and the second urging member pushes the second rectilinear portion while the first urging member is urging. The lens barrel according to claim 7 , wherein the lens barrel is pressed against the second surface. Each of the first urging member and the second urging member is a leaf spring, and the width of the second urging member is wider than the width of the first urging member in the circumferential direction of the cam ring. The lens barrel according to claim 9, which is characterized by: And a component block that is disposed in the first groove, has the first surface, and divides the force received by the first surface into a force in a direction perpendicular to the optical axis and a force in the optical axis direction. The lens barrel according to claim 9 or 10 . Imaging apparatus characterized by having a lens barrel according to any one of claims 1 to 11.