JP2018132694A - Image tremor correction device and lens device equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image tremor correction device or a lens device equipped with the image tremor correction device that can easily obtain desired strength of self holding in a state where an actuator of a lock mechanism is not driven controlled without employing a latch solenoid as the actuator of the lock mechanism.SOLUTION: An image tremor correction device or a lens device equipped with the image tremor correction device according the present invention are characterized in that an insertion hole for a lock pin to be inserted into or pulled out is formed in a tremor correction lens mirror chamber so that a movement of a movable member stays in a locked or lock-released state on a plane vertical to an optical axis, a rack engaging with a lock gear fixed to an output shaft of a lock motor is formed in a lateral face of the lock pin, and a shape of a lock rotation stopper fixed to the output shaft of the lock motor has a plane for limiting rotation of the lock gear through reception of urging force from a lock plate in the lateral face.SELECTED DRAWING: Figure 3

Description

  The present invention corrects image blur by moving a part of the optical system of the photographic lens in a direction having a component perpendicular to the optical axis in order to correct image blur in an imaging apparatus or lens apparatus including a photographic lens. The present invention relates to an image blur correction apparatus.

  In particular, the present invention relates to a lock mechanism of an image blur correction device for mechanically restricting movement of a movable member that moves on a plane perpendicular to an optical axis at the time of image blur correction at a predetermined timing.

  In an imaging apparatus or a lens apparatus provided with a photographing lens, it is required to mount an image blur correction apparatus that corrects an image blur caused by a user's camera shake or vibration transmitted to the apparatus.

  Image blur correction methods are roughly classified into mechanical and software methods, and various systems have been proposed. In particular, a lens shift system that corrects image blur by moving a part of the optical system of the photographic lens in a direction having a component perpendicular to the optical axis is widely used in imaging devices or lens devices.

  In a lens shift type image blur correction device, a camera shake correction lens which is a part of an optical system of a photographing lens and a mirror chamber holding the blur correction lens are imaged while detecting a current position by an actuator such as a VCM (voice coil motor). The image blur is corrected by moving the image so as to cancel the image blur on the surface.

  On the other hand, in the lens shift type image blur correction device, it is necessary to mechanically limit the movement of the blur correction lens and the blur correction lens chamber which are movable members at a predetermined timing when image blur is not corrected.

  When the image blur is not corrected, the movable member of the image blur correction device is not driven and controlled by the actuator. Therefore, unless the movement of the movable member is mechanically limited, the movable member is moved by an external force applied to the imaging device or the lens device. There is a possibility that the lens barrel may be damaged by colliding with a member inside the lens barrel as it is affected by gravity or inertial force. Even when the movable member is not damaged, the quality of the entire product is deteriorated due to the repeated occurrence of sound by the movable member colliding with the fixed member when carrying the imaging device or the lens device. There is a fear.

  Conventionally, a technique related to a lock mechanism for restricting movement of a movable member of an image blur correction apparatus when image blur is not corrected is disclosed in Patent Document 1 and the like.

  In Patent Document 1, a latch solenoid is employed as an actuator of a lock mechanism that operates and fixes a lock pin when a shake correction lens is not performing a shake correction operation, and this latch solenoid is substantially aligned with an optical axis in a lens barrel. By arranging the longitudinal direction in the tangential direction of the circle centering on the optical axis on the orthogonal plane, the limited arrangement space in the lens barrel can be effectively used to Techniques for arranging actuators are disclosed.

JP 2003-241059 A

  However, the technique disclosed in Patent Document 1 has the following problems.

  The latch solenoid described in Patent Document 1 is an actuator that generates a magnetic force by energizing a coil wound around a plunger, and adsorbs the plunger by the generated magnetic force to drive it straight. Further, the latch solenoid is provided with a permanent magnet to attract and hold the plunger, and even after the energization to the coil is stopped, the attracted state can be held by the permanent magnet.

  On the other hand, when a latch solenoid is used as an actuator for devices that often receive external force when carried, such as an imaging device or a lens device, external force exceeding the attractive force of the permanent magnet of the latch solenoid is applied to the device, and self-holding cannot be maintained. There is a fear.

  In particular, when a latch solenoid is used as an actuator of the movable member locking mechanism in the image blur correction device, the external force is applied to the device, so that the self-holding of the latch solenoid is released and the movable member is inadvertently unlocked. There is a risk that.

  In order to improve the self-holding strength of the latch solenoid as a countermeasure, a measure to increase the attracting force of the permanent magnet can be considered. The disadvantages due to the increase and the weight and size increase. In addition, it is not efficient to develop the latch solenoid itself in accordance with the layout space required for each imaging device or lens device and the specification of the attractive force of the permanent magnet.

  Therefore, the present invention does not employ a latch solenoid as an actuator for the lock mechanism, and an image blur correction apparatus that can easily obtain a desired self-holding strength when the actuator of the lock mechanism is not driven and controlled. It aims at providing the lens apparatus which mounts.

  In order to solve the above problems, an image blur correction apparatus according to a first aspect of the present invention is an image blur correction that corrects image blur by moving a part of the optical system of the photographing lens in a direction having a component perpendicular to the optical axis. An apparatus comprising: a shake correction lens; a movable member having a shake correction lens mirror chamber for holding the shake correction lens; a lock motor; a lock gear fixed to an output shaft of the lock motor and a lock gear rotation stop; A lock pin disposed perpendicular to the output shaft of the lock motor, and a fixing member having a lock plate that applies a biasing force to the side surface of the lock gear rotation stop toward the output shaft of the lock motor. Insertion into the correction lens mirror chamber for inserting and removing the lock pin so that the movement of the movable member is locked or unlocked on a plane perpendicular to the optical axis A rack that meshes with the lock gear fixed to the output shaft of the lock motor is formed on the side surface of the lock pin, and the shape of the lock rotation stopper is attached to the side surface from the lock plate. It has a plane for receiving the force to limit the rotation of the lock gear.

  In the image blur correction apparatus according to the second aspect of the present invention, the shape of the lock gear rotation stopper is a prism having an output shaft of the lock motor as an axial center.

  A lens apparatus according to a third aspect of the invention is a lens apparatus provided with the image blur correction apparatus of the first aspect or the second aspect.

  According to the present invention, an image blur correction device that does not employ a latch solenoid as an actuator of a lock mechanism and can easily obtain a desired self-holding strength in a state where the actuator of the lock mechanism is not driven and controlled, or the same Can be provided.

Schematic diagram showing the camera system Exploded perspective view showing image blur correction device The perspective view which shows the lock unit in an image blurring correction apparatus Sectional drawing which shows the mode of the state of the lock | rock of a lock mechanism in an image blurring correction apparatus, or lock release Sectional drawing which expands and shows the mode of the state of the lock mechanism of the image blurring correction device being locked or unlocked The perspective view of the lock unit which shows the modification of a present Example

  Embodiments of an image blur correction apparatus and a lens apparatus equipped with the image blur correction apparatus according to the present invention will be described below.

  With reference to FIG. 1, a description will be given of a method for correcting image blur in a camera system including an interchangeable lens, which is a lens device on which the image blur correcting device of this embodiment is mounted, and a camera body. FIG. 1 is a schematic diagram showing a camera system including an interchangeable lens on which the image blur correction apparatus of the present embodiment is mounted and a camera body.

  In FIG. 1, 100 is a camera body, 101 is an image sensor, 200 is an interchangeable lens, 201 is an optical system, 202 is a shake correction lens, 203 is a lens CPU, 204 is a shake correction actuator, 205 is an angular velocity sensor, and 206 is a lens position. A detection sensor is shown.

  The image blur correction method of the camera system including the interchangeable lens on which the image blur correction apparatus of the present embodiment is mounted and the camera body is a lens shift method. The lens shift method detects the angular velocity generated in the camera system due to camera shake, etc., calculates the angle blur from this, and cancels the image blur that occurs on the image sensor in accordance with the angle blur, so that part of the optical system is placed on the optical axis. This is a method of correcting image blurring that is moved in a direction having a component perpendicular to.

  The image blur correction method in the camera system of the present embodiment shown in FIG. 1 is as follows. First, the angular velocity generated in the camera system is detected by the angular velocity sensor 205. The detected angular velocities are sequentially transmitted to the lens CPU 203, and the lens CPU 203 calculates the angular blur from the angular velocities. The lens CPU 203 calculates the shift amount of the blur correction lens 202 for correcting the image blur generated on the image sensor 101 based on the calculated angular blur, and drives and controls the blur correction actuator 204 based on the shift amount. The blur correction lens 202 is moved on a plane perpendicular to the optical axis. At the same time, the lens CPU 203 detects the current position of the blur correction lens 202 from the lens position detection sensor 206, and compares the shift amount with the current position to move the blur correction lens 202 so as to satisfy the target shift amount. Check whether image blur correction has been completed. At the time of image blur correction, the blur correction lens 202 is moved on a plane perpendicular to the optical axis so that image blur occurring in the camera system is always corrected by repeating the above flow.

  Next, the configuration of the image blur correction device mounted on the interchangeable lens of this embodiment will be described with reference to FIG. FIG. 2 is an exploded perspective view of the image blur correction device mounted on the interchangeable lens of the present embodiment.

  In FIG. 2, 300 is an image blur correction device, 301 is a unit base, 302 is a blur correction lens, 303 is a blur correction lens mirror chamber, 304 is a lock unit, 305 is a lock unit presser, 306 is a coil, 307 is a magnet, 308 Denotes a yoke, 309 denotes a hall element, 310 denotes a position detection magnet, and 311 denotes a ball.

  The image blur correction apparatus 300 is unitized and incorporated in the lens barrel of the interchangeable lens 200. The image blur correction apparatus of the present invention is not limited to the unitized one as in the present embodiment, and a configuration in which a part of the optical system is moved in a direction having a component perpendicular to the optical axis for image blur correction. Anything satisfying the above is sufficient.

  The unit base 301 is a member that is the basis of each member constituting the image blur correction apparatus 300. The image blur correction device 300 is mounted on the interchangeable lens 200 by the unit base 301.

  The shake correction lens 302 and the shake correction lens mirror chamber 303 that holds the shake correction lens 302 are movable members of the image shake correction apparatus 300 that is moved on a plane perpendicular to the optical axis with respect to the unit base 301 at the time of image blur correction.

  In the image blur correction apparatus 300 of the present embodiment, members such as the blur correction lens 302 and the blur correction lens mirror chamber 303 that are moved on a plane perpendicular to the optical axis at the time of image blur correction are movable members. A member that is not moved during image blur correction is a fixed member.

  An insertion hole is formed in the blur correction lens mirror chamber 303 so that a lock pin of a lock unit 304, which will be described later, is inserted and removed so that the movement of the movable member is locked or unlocked.

  The ball 311 has a function of smoothly moving the movable member with respect to the fixed member on a plane perpendicular to the optical axis. In order to support the movable member with respect to the fixed member, three or more balls 311 are sandwiched between the fixed member and the movable member. In this embodiment, the ball 311 is sandwiched between a ball receiver formed on a member for fixing the yoke 308 and a ball receiver formed in the shake correction lens mirror chamber 303.

  The lock unit 304 constitutes a lock mechanism for mechanically restricting the movement of the movable member when image blur is not corrected. The configuration of the lock mechanism of the lock unit 304 will be described later. The lock unit 304 is fixed to the unit base 301 by fitting the outer shape of the lock unit 304 into the positioning restricting portion of the unit base 301 and holding the lock unit holder 305 to the unit base 301 with screws.

  In the image blur correction apparatus 300 of this embodiment, a VCM (voice coil motor) is employed as a blur correction actuator for moving the movable member. The VCM includes a coil 306 provided in a shake correction lens mirror chamber 303 constituting a movable member and a magnet 307 and a yoke 308 provided on a unit base 301 constituting a fixed member. By energizing and generating electromagnetic force, the VCM is driven and controlled to move the movable member relative to the fixed member. The VCM is driven and controlled by the lens CPU 203 in accordance with the angular blur calculated based on the angular velocity detected by the angular velocity sensor 205.

  The hall element 309 is a lens position detection sensor of the blur correction lens 302. The hall element 309 is mounted on a flexible substrate, and is fixed to a member for fixing the yoke 308 together with the yoke 308. Since the member for fixing the yoke 308 is integrated with the unit base 301, the Hall element 309 is provided on the fixing member side of the image blur correction apparatus 300. The hall element 309 detects magnetism according to the relative distance from the position detection magnet 310 provided in the shake correction lens mirror chamber 303 constituting the movable member, and acquires the current position of the movable member with respect to the fixed member. The lens CPU 203 compares the current position of the movable member acquired from the Hall element 309 with the shift amount, which is the target value of the shake correction lens 302, and controls the drive of the VCM while checking the image shake correction state.

  In the image blur correction apparatus 300 of this embodiment, the movable member is mechanically held around the optical axis by the lock mechanism of the lock unit 304 when image blur is not corrected.

  In an image blur correction apparatus that employs a lens shift method as an image blur correction method, the movable member only falls freely due to gravity, particularly when image blur is not corrected, such as when the camera system is turned off. At this time, in order to prevent the movable member from colliding with the fixed member inside the lens barrel due to the external force applied to the apparatus and damaging the inside of the lens barrel or generating collision noise, the movable member is used as the optical axis. It is necessary to lock mechanically on a vertical plane.

  A movable member locking mechanism in the image blur correction apparatus 300 of this embodiment will be described with reference to FIG. FIG. 3 is a perspective view showing the lock unit 304 in the image blur correction apparatus 300 of the present embodiment.

  3, 304a is a lock unit base, 304b is a lock motor, 304c is a flexible substrate, 304d is a lock gear, 304e is a lock rotation stop, 304f is a lock plate, and 304g is a lock pin.

  The lock unit 304 is not limited to being configured as a unit as in the present embodiment, and may be configured as a part of the unit base 301 of the image blur correction apparatus 300, for example. By configuring the lock unit 304 as a unit, there is an advantage that the same lock unit 304 can be easily mounted on various other types of lens devices.

  The lock unit base 304 a is a member that is a base of the members that constitute the lock unit 304. The lock unit 304 is fixed to the unit base 301 by fitting the outer shape of the lock unit base 304 a to the positioning restriction portion of the unit base 301 and pressing it with the lock unit presser 305.

  The lock motor 304b is a drive source for moving the lock pin 304g straight, and is an actuator of a lock mechanism that is driven and controlled by the lens CPU 203. A stepping motor, a DC motor, an ultrasonic motor, or the like can be used as the lock motor 304b.

  Supply of power and control signals to the lock motor 304b is performed by the flexible substrate 304c. The flexible substrate 304c is connected to the power supply terminal and the control signal terminal of the lens CPU 203.

  The lock motor 304b is disposed in the lock unit base 304a so that its output axis is perpendicular to the optical axis of the shake correction lens 302.

  A lock gear 304d and a lock rotation stop 304e are fixed to the output shaft of the lock motor 304b so as to rotate together.

  The lock pin 304g is arranged so as to be perpendicular to the output shaft of the lock motor 304b, and is configured to be able to move straight according to a guide hole formed in the lock unit base 304a. Further, since one end of the guide hole is configured to be covered by the lock unit presser 305 when the lock unit 304 is fixed to the image blur correction device 300, the lock pin 304g is dropped from the lock unit base 304a. There is nothing.

  A rack is formed on the side surface of the lock pin 304g, and the lock gear 304d is configured to mesh with the rack of the lock pin 304g.

  The lock plate 304f is fixed to the lock unit base 304a in a cantilever state, and the end of the lock plate 304f that is not fixed to the lock unit base 304a is locked so as to generate a biasing force toward the output shaft of the lock motor 304b. It contacts the side surface of the rotation stop 304e.

  In the lock mechanism of the lock unit 304, the lock pin 304 g is linearly moved by drivingly controlling the lock motor 304 b, and the tip of the lock pin 304 g is inserted into and removed from the insertion hole formed in the shake correction lens mirror chamber 303. The movable member is brought into a locked or unlocked state.

  When the lock motor 304b is driven and controlled, its output shaft rotates, and a lock gear 304d and a lock rotation stop 304e fixed coaxially with the output shaft rotate together.

  The racks formed on the side surfaces of the lock gear 304d and the lock pin 304g mesh with each other, and the lock pin 304g moves straight by the rotation of the lock gear 304d. At this time, the vertical movement direction of the lock pin 304g is controlled by the forward and reverse rotation directions of the lock motor 304b. When the lock pin 304g is moved downward, the tip of the lock pin 304g is inserted into the insertion hole formed in the vibration reduction lens mirror chamber 303 so that the movable member cannot move on a plane perpendicular to the optical axis. On the contrary, when the lock pin 304g is moved upward, the movable member is in a unlocked state in which the movable member can move on a plane perpendicular to the optical axis.

  The lock rotation stop 304e is rotated together with a lock gear 304d coaxially fixed to the output shaft of the lock motor 304b by drive control of the lock motor 304b, and receives a biasing force from the lock plate 304f when the drive of the lock motor 304b is not controlled. The lock pin 304g has a function of limiting the rotation of the lock gear 304d so that the lock pin 304g is maintained in a locked or unlocked state.

  The lock rotation stop 304e has a shape having a flat surface on the side surface, and the lock rotation stop 304e in the present embodiment has a quadrangular prism shape having four flat surfaces on the side surface. By forming the lock rotation stopper 304e in such a shape, the rotation is limited only when the lock rotation stopper 304e receives an urging force from the lock plate 304f on the side plane, and the lock pin 304g is locked or locked. A lock mechanism that is stably maintained in any state of release can be configured.

  The state of the locked or unlocked state of the movable member of the lock mechanism and the function of the lock rotation stop 304e will be described with reference to FIGS.

  FIG. 4 is a cross-sectional view showing a locked or unlocked state of the movable member of the lock mechanism of the lock unit 304 in the present embodiment. FIG. 4A is a state where the movable member is in a locked state, and FIG. (C) shows the time when the movable member is in the unlocked state when the transition from the locked state to the unlocked state. FIG. 5 is an enlarged cross-sectional view of a portion surrounded by a broken line in the cross-sectional view showing each state of FIG.

  As shown in FIGS. 4A and 5A, when the movable member is in the locked state, the tip of the lock pin 304g is inserted into the insertion hole formed in the shake correction lens mirror chamber 303, and the lock rotation is stopped. 304e receives a biasing force from the lock plate 304f on the side plane A, and its rotation is restricted, so that the movable member is stably locked.

  When the lock rotation stop 304e is rotated against the urging force from the lock plate 304f by driving and controlling the lock motor 304b as shown in FIGS. 4B and 5B, the lock rotation stop 304e The urging force from the lock plate 304f is received at the corner between the plane A and the plane B.

  At this time, since the urging force received by the corner sandwiched between the plane A and the plane B on the side surface of the lock rotation stopper 304e from the lock plate 304f becomes unstable, the lock rotation stopper 304e is the plane A or plane B and the lock plate 304f. Attempts to rotate to receive urging force from Accordingly, due to the rotation of the lock rotation stop 304e by the urging force from the lock plate 304f, the lock pin 304g is moved to the locked or unlocked position without being stopped at a halfway position, and is stably maintained. The Rukoto.

  As shown in FIGS. 4C and 5C, when the movable member is in the unlocked state, the tip of the lock pin 304g is pulled out from the insertion hole formed in the shake correction lens mirror chamber 303, and the lock rotation is performed. The stop 304e receives a biasing force from the lock plate 304f on the side surface plane B and is restricted from rotating, thereby stably maintaining the unlocked state of the movable member.

  In the locked and unlocked states of FIGS. 4 (a) and 4 (b), the lock rotation stopper 304e is restricted in rotation by receiving a biasing force from the lock plate 304f on the side surface, so that, for example, image blurring is performed. Even when an external force is applied to the correction device 300, the lock pin 304g does not move, and the locked or unlocked state of the movable member is not inadvertently changed, and either state is stably maintained. It becomes possible to do.

  Further, it is possible to easily adjust the urging force of the lock plate 304f simply by changing the thickness, plate width, and material of the lock plate 304f, and the image blur correction device 300 can be changed without changing the specification of the lock motor 304b. In addition, the strength of maintaining the locked or unlocked state can be easily adjusted. Further, by adopting a higher torque performance as the lock motor 304b, it becomes possible to adopt the lock plate 304f having a larger urging force, and the strength of maintaining the locked or unlocked state is increased and the reliability is increased. It is possible to configure a lock mechanism of the image blur correction apparatus 300 having a high image quality.

  In this embodiment, the lock rotation stopper 304e has a quadrangular prism shape, and the urging force from the lock plate 304f is received every 90 degrees on the side plane to limit the rotation of the lock gear 304d. The shape of the rotation stopper is not limited to a square pole. The lock rotation stopper can achieve the effect of the present invention by having a shape having a flat surface for receiving the urging force from the lock plate on the side surface. For example, when the shape of the lock rotation stopper is a hexagonal column, it is possible to limit the rotation of the lock gear by receiving the urging force from the lock plate every 60 degrees on the side plane.

  The shape of the cross section perpendicular to the axis of the lock rotation stopper does not need to be a strict regular polygon, and the surface connecting the planes of the lock rotation stopper is formed with an R shape so that it can be locked during drive control of the lock motor. It is good also as comprising so that the urging | biasing force applied to a lock | rock rotation stop from a board may change smoothly.

  Further, as a modification of the present embodiment, as shown in FIG. 6, a torsion spring or the like that directly applies an urging force to the lock gear toward the output shaft of the lock motor is provided so that the lock gear rotates when the lock motor is not driven and controlled. By adopting a configuration that is limited by the frictional force with the torsion spring, the lock pin may be prevented from being inadvertently moved by an external force applied to the device.

  In addition, the present invention can be applied to an image blur correction apparatus that employs an image sensor shift method. The image sensor shift method is a method of correcting image blur by moving the image sensor on a plane perpendicular to the optical axis in accordance with angle blur generated in the apparatus due to camera shake or the like. When the present invention is applied to the image sensor shift method, an insertion hole may be formed in a substrate on which the image sensor is mounted or a frame that holds the image sensor, and a lock pin may be inserted and removed.

  As described above, according to the present invention, even when an external force is applied to the apparatus, the lock pin can be stably maintained without being moved inadvertently. It is possible to provide an image blur correction device capable of easily adjusting the strength for maintaining the unlocked state by changing the leaf spring and a lens device including the image blur correction device.

DESCRIPTION OF SYMBOLS 100 Camera main body 101 Image pick-up element 200 Interchangeable lens 201 Optical system 202 Shake correction lens 203 Lens CPU
204 Blur correction actuator 205 Angular velocity sensor 206 Lens position detection sensor 300 Image blur correction device 301 Unit base 302 Blur correction lens 303 Blur correction lens mirror chamber 304 Lock unit 304a Lock unit base 304b Lock motor 304c Flexible substrate 304d Lock gear 304e Lock rotation stop 304f Lock plate 304g Lock pin 305 Lock unit presser 306 Coil 307 Magnet 308 Yoke 309 Hall element 310 Position detection magnet 311 Ball

Claims (3)

An image blur correction apparatus that corrects image blur by moving a part of an optical system of a photographing lens in a direction having a component perpendicular to the optical axis,
A movable member having a blur correction lens and a blur correction lens mirror chamber for holding the blur correction lens;
A lock motor, a lock gear fixed to the output shaft of the lock motor and a lock gear rotation stop, a lock pin arranged perpendicular to the output shaft of the lock motor, and the lock gear rotation toward the output shaft of the lock motor A fixing member having a lock plate for applying a biasing force to the side surface of the stop,
An insertion hole for inserting and removing the lock pin is formed in the blur correction lens mirror chamber so that the movement of the movable member is locked or unlocked on a plane perpendicular to the optical axis,
A rack that meshes with the lock gear fixed to the output shaft of the lock motor is formed on a side surface of the lock pin,
The shape of the lock rotation stopper has a flat surface for receiving the urging force from the lock plate on the side surface to limit the rotation of the lock gear.   2. The image blur correction device according to claim 1, wherein the shape of the lock gear rotation stopper is a prism having an output shaft of the lock motor as an axial center.   A lens apparatus comprising the image blur correction apparatus according to claim 1.

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