JP2017215390A - Lens device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lens device in which a cam drive group does not contact with an actuator drive group even when a zoom mechanism is operated in a non-energized state of the lens device so as to prevent the lens group and the lens holding frame from being damaged and be free of the risk that the cam part has a flaw.SOLUTION: A lens device comprises: a first movable frame which holds a first optical member, includes a first cam follower engaged with a first cam groove formed in a cam barrel, and moves in an optical axis direction along the first cam groove; a second movable frame which holds a second optical member; an actuator which moves the second movable frame in the optical axis direction; and a collision prevention member which is arranged between the first movable frame and the second movable frame, includes an elastic member at a portion abutting against the second movable frame and an engaging part engaged with a second cam groove formed in the cam barrel, and moves in the optical axis direction along the second cam groove. The collision prevention member contacts with the second movable frame in advance of the first movable frame in a non-energized state of the actuator.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a lens apparatus, and more particularly to a lens apparatus using cam drive and actuator drive.

  2. Description of the Related Art Conventionally, in a lens apparatus having a moving lens that can move in the optical axis direction, such as a zoom lens unit and a focus lens unit, a structure in which a lens holding frame holding a moving lens is driven in the optical axis direction by a linear actuator is known. Yes. For example, there is a lens apparatus that drives the zoom mechanism only by a user's manual operation and drives the focus lens unit for the zoom mechanism only by an actuator. In the case of such a lens device, the focus lens unit and the surrounding structure are simplified, so that the focus lens unit can be reduced in size.

  However, since the focus lens unit is driven by an actuator, if the zoom mechanism is operated while the lens apparatus is not energized, the zoom lens unit may come into contact with the focus lens unit and be damaged depending on the stop position of the focus lens unit. Further, when the lens holding frames come into contact with each other, there is a possibility that a dent is generated on the cam portion of the zoom lens unit that is cam-driven, and a stable zoom operation cannot be performed.

  Patent Document 1 discloses a proposal for preventing damage caused by contact between lens holding frames by providing a spring-like elastic member on the lens holding frame and contacting the elastic member before the lens holding frames contact each other. Yes.

  Patent Document 2 discloses a proposal that includes a reserve power supply and retracts the actuator drive group to a position where the lens group or the lens holding frame does not come into contact with each other when the power is supplied.

JP 2010-243877 A Japanese Patent No. 5102146

  However, in Patent Document 1 described above, an elastic member is provided on the lens holding frame and the elastic member is brought into contact first. However, since the lens holding frames are in indirect contact with each other, when a large impact is received, It is not possible to prevent dents in the part.

  In Patent Document 2, a reserve power supply is required to retract the actuator drive group to a position where it does not come into contact with the cam drive group, leading to an increase in the size and cost of the lens device.

  Therefore, an object of the present invention is to prevent the cam drive group and the actuator drive group from coming into contact with each other even when the zoom mechanism is operated while the lens device is in a non-energized state. It is an object of the present invention to provide a lens device that does not have a risk of having a dent on the surface.

In order to achieve the above object, a lens apparatus according to the present invention includes:
A first movement that holds the first optical member and includes a first cam follower that engages with a first cam groove formed in the cam cylinder, and moves in the optical axis direction along the first cam groove. A frame, a second moving frame for holding the second optical member, an actuator for moving the second moving frame in the optical axis direction, and between the first moving frame and the second moving frame. An elastic member is provided at a position that is positioned and abutted with the second moving frame, and an engaging portion that engages with a second cam groove formed in the cam cylinder is provided, and light is emitted along the second cam groove. An anti-collision member that moves in the axial direction, and the anti-collision member contacts the second moving frame prior to the first moving frame in a state where the actuator is not energized. It is characterized by.

  According to the present invention, even when the zoom mechanism is operated while the lens device is in a non-energized state, the cam drive group and the actuator drive group do not come into contact with each other, and the lens group and the lens holding frame are prevented from being damaged. It is possible to provide a lens device that does not cause a dent.

Sectional view when each lens holding frame of the lens device is located at the telephoto end Sectional view when each lens holding frame of the lens device is positioned at the wide-angle end Sectional view when the lens holding frames 32 and 33 are closest when the lens device is in a non-energized state Sectional view when the anti-collision member and the lens holding frame 33 come into contact with the zoom ring when the lens device is in a non-energized state Plan view of collision prevention member Cam groove provided on the cam cylinder and guide groove provided on the fixed cylinder

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 shows a cross-sectional view of the lens apparatus 1 in this embodiment when it is positioned at the telephoto end. FIG. 2 shows a cross-sectional view of the lens device 1 in this embodiment when it is positioned at the wide angle end. FIG. 3 is a cross-sectional view when the lens holding frames 32 and 33 are closest to each other when the lens apparatus 1 is energized. FIG. 4 is a cross-sectional view when the zoom ring 2 is rotated by the user and the collision preventing member 14 comes into contact with the lens holding frame 33 before the lens holding frame 32 when the lens device is in a non-energized state. FIG. 5 is a plan view of the collision preventing member 14. 6 shows the cam grooves 4a and 4b of the lens holding frames 31 and 32 provided on the cam cylinder 4, the cam groove 4d of the collision preventing member 14, and the lens holding frames 31 and 32 provided on the fixed cylinder 3 and the collision prevention. The guide grooves 3a, 3b, 3d of the member 14 are shown. Each solid line is a cam groove provided in the cam cylinder 4, and a dotted line is a guide groove provided in the fixed cylinder 3. An arrow 40a indicates a subject side, an arrow 40b indicates an image sensor side, an arrow 50a indicates a wide-angle end side, and an arrow 50b indicates a telephoto end side.

  The mechanism of the zoom unit will be described with reference to FIGS.

  The lens device 1 includes a plurality of lens groups, and a front lens fixed group 10 and a relay lens group (not shown) are arranged before and after the zoom unit. The lens groups 11, 12, and 13 are held by lens holding frames 31, 32, and 33, respectively.

  As shown in FIG. 6, the cam cylinder 4 is provided with cam grooves 4 a, 4 b, and 4 d describing the locus of the lens holding frames 31 and 32 and the collision preventing member 14 in the optical axis direction 30. It is arranged inside the fixed cylinder 3 so as to be rotatable around the optical axis direction 30. Here, the cam grooves 4b and 4d have the same track, and the lens holding frame 32 and the collision prevention member 14 move back and forth along the optical axis direction 30 along the optical axis direction 30 by a zoom operation.

  Guide grooves 3 a, 3 b, 3 c, and 3 d that allow the lens holding frames 31, 32, and 33 and the collision prevention member 14 to slide along the optical axis direction 30 are attached to the fixed cylinder 3.

  In the lens holding frames 31 and 32, guide grooves 3a and 3b provided in the fixed cylinder 3 and cam followers 5a and 5b engaged with the cam grooves 4a and 4b provided in the cam cylinder 4 are provided around the optical axis direction 30. Is attached to multiple.

  The lens holding frame 33 is provided with a plurality of cam followers 5 c around the optical axis direction 30 that engage with guide grooves 3 c provided in the fixed cylinder 3. The lens holding frame 33 is provided with a mover 17.

  The fixing member 18 applies a pressing force to the moving element 17 and is fixed to the fixed cylinder 3. By applying a voltage to the moving element 17 by a voltage supply means (not shown) to generate a driving force, the lens holding frame 33 and the moving element 17 are caused to move straight by the guide groove 3c provided in the fixed cylinder 3. , Move back and forth along the optical axis direction 30.

  The zoom ring 2 is rotatable around the optical axis direction 30 and is fitted to the fixed cylinder 3 and is connected to the cam cylinder 4 via a connecting pin 9. When the zoom ring 2 is rotated, the cam cylinder 4 is also rotated, and the lens holding frames 31 and 32 are predetermined in the optical axis direction 30 by the rectilinear guide action by the cam grooves 4a and 4b and the guide grooves 3a and 3b. Move back and forth along the trajectory. The lens holding frame 33 is electrically driven and controlled, and moves back and forth to a predetermined position along the optical axis direction 30 as the zoom ring 2 rotates.

  As described above, the lens holding frames 31, 32, and 33 move from the telephoto end shown in FIGS. 1 and 2 to the wide-angle end along the optical axis direction 30 to change the lens interval, thereby performing a zoom operation.

  Next, the mechanism of the focus unit will be described. The focus ring 19 is rotatable around the optical axis direction 30 and is fitted to the fixed cylinder 3. By rotating the focus ring 19 around the optical axis direction 30, the lens holding frame 33 that is electrically driven and controlled moves back and forth along the optical axis direction 30 to a predetermined position.

  Thus, the focusing operation is performed by changing the lens interval between the lens holding frames 32 and 33.

  Next, the collision preventing member 14 will be described.

  As shown in FIG. 5, the collision preventing member 14 has a cam groove 4d provided in the cam cylinder 4 and an engaging portion 8 engaged with the guide groove 3d provided in the fixed cylinder 3, and the cam groove 4d. And is engaged with the guide groove 3d. In addition, the elastic member 15 is provided at a location where the lens holding frame 33 comes into contact. The elastic member 15 may be any member that suppresses an impact caused by the contact between the collision preventing member 14 and the lens holding frame 33, and is, for example, a rubber member or a sponge-like member. A spring member 16 is provided between the lens holding frame 32 and the collision preventing member 14.

  Thereby, the urging force is applied to the lens holding frame 32 toward the subject, and the collision preventing member 14 is applied to the imaging device. Here, since the lens holding frame 32 and the collision preventing member 14 move back and forth along the optical axis direction 30 along the same locus by the cam grooves 4b and 4d, the distance between the lens holding frame 32 and the collision preventing member 14 in the optical axis direction 30 is increased. Is constant. Therefore, the urging force of the spring member 16 acting on the lens holding frame 32 and the collision preventing member 14 is constant, and the play in the optical axis direction 30 generated in the cam follower 5b and the cam groove 4b of the lens holding frame 32 is stably suppressed. Can do.

  Next, the operation of the collision preventing member 14 will be described.

  As shown in FIG. 3, the zoom ring 2 is operated in a state where power is supplied to the lens device 1, and the lens holding frames 32 and 33 are closest to each other. The gap is secured. Therefore, when the electric power is supplied to the lens device 1, the collision preventing member 14 and the lens holding frame 32 are in a positional relationship that does not contact the lens holding frame 33.

  Here, when the lens device 1 is in a non-energized state and the user operates the zoom ring 2, the lens holding frames 31, 32 and the collision preventing member 14 move back and forth along the optical axis direction 30 along the locus of the respective cam grooves. To do. However, the lens holding frame 33 that is electrically driven by the movable element 17 does not correspond to the rotation of the zoom ring 2 and maintains the lens position in the optical axis direction 30 because the lens device 1 is in a non-energized state. At this time, as shown in FIG. 4, when the lens holding frame 32 and the collision preventing member 14 approach the lens holding frame 33 by cam driving, the elastic member 15 of the collision preventing member 14 holds the lens before the lens holding frame 32. The positional relationship is in contact with the frame 33.

  As described above, according to the present embodiment, a collision prevention member is provided between the cam drive group and the actuator drive group, and the cam drive group and the collision prevention member are driven by the cam groove of the same locus, thereby providing a non-energized state. It is possible to prevent damage due to contact between the cam drive group and the actuator drive group. In addition, since the lens holding frames are not brought into contact with each other, it is possible to prevent dents on the cam portion of the cam driving group and to perform a stable zoom operation.

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

1 lens device, 2 zoom ring, 3 fixed cylinder, 3a-3d guide groove, 4 cam cylinder,
4a, 4b, 4d cam groove, 5a to 5c cam follower, 8 engaging portion,
14 collision prevention member, 15 elastic member, 16 spring member, 17 actuator,
19 Focus ring, 30 Optical axis, 31, 32, 33 Lens holding frame

Claims (3)

A first movement that holds the first optical member and includes a first cam follower that engages with a first cam groove formed in the cam cylinder, and moves in the optical axis direction along the first cam groove. Frame,
A second moving frame for holding the second optical member;
An actuator for moving the second moving frame in the optical axis direction;
An elastic member is engaged with a second cam groove formed in the cam cylinder at a position that is located between the first moving frame and the second moving frame and is in contact with the second moving frame. A collision preventing member that includes an engaging portion and moves in the optical axis direction along the second cam groove;
The lens device, wherein the collision preventing member contacts the second moving frame prior to the first moving frame in a state where the actuator is not energized. The lens apparatus according to claim 1, wherein a spring member that contacts each of the first moving frame and the collision preventing member is provided. The lens apparatus according to claim 1, wherein the actuator is any one of a vibration type actuator, a voice coil motor, a stepping motor, an AC motor, and a DC motor.