JP5592732B2 - Zoom lens barrel - Google Patents

Description

  The present invention relates to a zoom lens barrel that includes a retractable lens frame and whose overall length in a non-shooting state is shorter than that in a shooting state.

  As a conventional zoom lens barrel, the one disclosed in Patent Document 1 is a zoom lens barrel whose overall length in a retracted state, which is a non-shooting state, is shorter than that in a shooting state. As shown in FIGS. 17 and 18, the lens barrel A1 holds a fixed frame A2 that supports each lens frame member, a rotary frame A3, a zoom drive source, a focus drive source, and a retractable lens A23, and The projection A10h protrudes to the side, is driven by the zoom drive source, and in the shooting state, the retractable lens A23 is positioned on the optical path, and projects outside the optical path in conjunction with the transition from the shooting state to the retracted state. A retractable lens frame A10 that rotates and retracts together with the portion 10h, and a focus lens frame A13 that holds the focus lens and is driven forward and backward by the focus drive source.

  The focus lens frame A13 does not come into contact with the retractable lens frame A10 when driven in the retracted direction shortened from the photographing state, and retracted when an abnormal drive occurs during the driven state in the retracted retractable direction. Abutting the projection A10h of the frame A10, and guiding the projection along the rotation trajectory of the projection during contact with the projection, the retraction lens frame A10 and the rear lens frame A13 A guide locus portion A13c for preventing the interference is provided.

  In the conventional zoom lens barrel A1, the retracting cam A14 is fixed to the back side of the fixed frame A2 as a cam member for retracting the retracting lens frame A10 out of the optical path. Specifically, the retracting cam A14 protrudes and is fixed to the front side of the photographic lens optical axis O direction on the holding plate A15 on the back side of the fixed frame A2. A sensor base A16 on which the image sensor unit is mounted is mounted on the back surface of the holding plate A15. When the retracting cam A14 moves relatively close to the retracting lens frame A10 during the transition from the photographing state to the retracted state, the retracting lens comes into contact with the driven pin A10c provided on the retracting lens frame A10 and slides. The frame A10 is rotationally driven to the retracted position outside the optical path (FIG. 17).

JP 2009-25557 A

  In the zoom lens barrel A1 disclosed in Patent Document 1 described above, a retracting cam A14 for retracting the retracting lens frame A10 is fixed on the holding plate A15 on the back side of the fixed frame A2. The holding plate A15 is coupled to the sensor base A16. On the sensor base A16, an image pickup unit A26 including an image pickup device, an optical filter, and the like is disposed. When the retracting cam A14 is arranged on the holding plate A15, the degree of freedom of arrangement of the imaging unit A26 is lost, and design restrictions are imposed. In particular, when the image pickup unit has a blur correction function, the space is further limited, which may hinder downsizing.

  Further, since the retracting cam A14 is disposed on the holding plate A15 on the back side of the fixed frame A2, the retracting lens frame A10 is used in the partially assembled lens barrel before the mounting of the holding plate A15 and the sensor base A16. Therefore, there is also a problem that it is not possible to confirm the advance / retreat state of each lens frame including the evacuation cam A14.

  Further, the retracting cam A14 needs to be inserted through the side of the focus lens frame A13 disposed on the rear side of the retracting lens frame A10, which restricts the shape and arrangement of the focus lens frame A13.

  Furthermore, the rotation angle from the position on the optical path of the retractable lens frame A10 to the retracted position outside the optical path is large, and the driven pin A10c of the retractable lens frame A10 that contacts the retracting cam A14 in order to secure the rotational angle. It is necessary to arrange the position closer to the rotational axis. When such an arrangement is applied, it is difficult to accurately rotate the retractable lens frame A10 to the retracted position, and it is necessary to allow a large margin in consideration of some variation in the retracted position. From this point, it is difficult to sufficiently reduce the size of the lens barrel.

  The present invention has been made to solve the above-described problem, and in a zoom lens barrel having a retractable lens frame that is retracted in a non-shooting state, the retracting mechanism of the retractable lens frame is a cam for driving the retracting of the lens frame. It is an object of the present invention to provide a zoom lens barrel that can be downsized without restricting the arrangement of grooves and the arrangement of image pickup units.

In order to solve the above-described problems, a zoom lens barrel according to the present invention includes a fixed lens, a zoom drive source for zooming, and the zoom drive. A first frame that is at least rotationally driven by the source relative to the fixed frame and includes a cam groove portion; a second frame that is driven forward and backward by the first frame and includes a cam portion; and A third frame that is driven back and forth by the first frame, and a frame that is rotatably supported by the third frame, and holds the retractable lens; Is in the approach position located on the optical path, and the cam groove portion of the first frame and the cam portion provided on the second frame during the switching operation period from the shooting state to the non-shooting state. Rotation drive, the retractable lens Comprising the aforementioned retractable lens frame that is retracting to the retracted position retracted outside the road, and the retractable lens frame, the first half in the first of the switching operation period from the photographing state to the non-shooting state It is rotationally driven toward the retracted position by the cam groove of the frame, and is rotationally driven so as to be positioned at the retracted position by the cam provided in the second frame in the second half. .

  According to the present invention, in a zoom lens barrel having a retractable lens frame that is retracted in a non-photographing state, the retracting mechanism of the retractable lens frame restricts the arrangement of the cam groove for driving the lens frame forward and backward and the arrangement of the imaging unit. Therefore, it is possible to provide a zoom lens barrel that can be downsized.

1 is a front view of a zoom lens barrel according to an embodiment of the present invention in a retracted state that is a non-photographing state. It is AA sectional drawing of FIG. 1 is a longitudinal sectional view in a zoom wide state that is a photographing state of the zoom lens barrel of FIG. FIG. 1 is a rear view of the zoom lens barrel of FIG. 1 with the third group zoom frame, the fourth group focus frame, and the rear imaging unit removed. The perspective view which looked at the state which removed the 3 group zoom frame, the 4 group focus frame, and the back side imaging unit in the retracted state of the zoom lens barrel of FIG. FIG. 1 is a rear view of the zoom lens barrel in FIG. 1 with the fourth group focus frame and the rear imaging unit removed in the zoom wide state. The perspective view which looked at the state which removed the 4 group focus frame and the imaging unit of the back side in the zoom wide state of the zoom lens barrel of FIG. 1 from the back side The perspective view which looked at the cam frame applied to the zoom lens barrel of FIG. 1 from the back side 9 is a developed view of the cam groove on the inner peripheral surface of the cam frame in FIG. Rear view of a two-group zoom frame applied to the zoom lens barrel of FIG. It is BB sectional drawing of FIG. The rear view in the zoom wide state of the 3 group zoom frame holding the retractable lens frame applied to the zoom lens barrel of FIG. The perspective view which looked at the 3 group zoom frame of Drawing 12 from the back side Rear view of retractable lens frame shown in FIG. When the lens barrel of FIG. 3 is driven to be switched from the zoom wide state to the retracted state, the second group zoom frame, the cam follower of the third group zoom frame, and the retractable lens frame with respect to the cam groove on the inner peripheral surface of the cam frame of FIG. Enlarged view showing the relative sliding movement of the driven pin FIG. 15 is a cross-sectional view corresponding to FIG. 15 showing a state in which the contact follower of the retractable lens frame of FIG. 12 moves relative to the protrusion cam of the second group zoom frame of FIG. A longitudinal sectional view of a conventional zoom lens barrel retracted FIG. 17 is a longitudinal sectional view of the conventional zoom lens barrel in FIG. 17 in the zoom wide state.

Hereinafter, embodiments of the present invention will be described.
A zoom lens barrel 1 as an embodiment of the present invention will be described with reference to FIGS.

  In the zoom lens barrel 1, each lens frame is housed in a fixed frame, and each lens frame is extended from a shortened retracted state, which is a non-photographing state, to switch to a photographing state (strictly, a photographing state). In this photographing state, there is a lens barrel capable of zooming from a zoom wide (hereinafter referred to as a wide state) to a zoom telephoto state (hereinafter referred to as a tele state), and further provided with a camera shake correction function.

  In the following description, the optical axis of the photographing lens is O, and the subject side is the front and the imaging side is the rear (back side) in the optical axis O direction. Moreover, the rotation direction of each member is shown by the rotation direction seen from the back side. Of the directions orthogonal to the optical axis O, the left-right direction is the X direction and the up-down direction is the Y direction in a normal camera photographing posture.

  As shown in FIGS. 1 to 3, the zoom lens barrel 1 is supported by the fixed frame 2, the rotary frame 3 supported by the fixed frame 2 and driven to rotate forward and backward during zooming and retracting driving, and the rotary frame 3 in a rotation restricted state. A moving frame 4 that moves forward and backward together, a cam frame 5 that rotates together with the rotating frame 3, and a first frame that moves forward and backward, a rectilinear guide frame 6 that moves forward and backward with the cam frame 5 in a rotationally restricted state, and a fixed frame 2. A sensor unit support plate 16 that supports the sensor unit 15 on the back surface of the lens and that can be displaced in the X and Y directions is provided. Further, as a lens frame that is driven to move forward and backward under a rotation restricted state, a group zoom is sequentially performed from the front side. A frame 7, a second group zoom frame 8 as a second frame, a third group zoom frame 9 as a third frame that supports the retractable lens frame 12, and a fourth group focus frame 13, and the first group zoom frame 7 as a photographing optical system. 1 group lens 31 and 2 group held in A second lens group 32 held in the lens frame 8, a retractable lens 33 which is a third lens group held in the retractable lens frame 12, and a fourth lens group 34 which is a focusing lens held in the fourth lens focus frame 13. I have.

  The fixed frame 2 is a member having a cylindrical inner peripheral part, and a groove part formed by connecting a helicoid part inclined with respect to the optical axis O and a front circumferential groove part along the circumference to the inner peripheral part, A rectilinear groove along the optical axis O is provided. A zooming unit including a zoom motor, a gear train, and a long gear (not shown) as a zoom driving source housed in the unit housing portion 41. A focusing unit including a focus motor 42, a gear train, a feed screw, and a guide shaft, which is a unit for performing focusing driving of the photographic lens. The long gear (not shown) is supported in a state exposed to the inner peripheral portion of the fixed frame 2 along a direction parallel to the optical axis O.

  The rotating frame 3 is a cylindrical member, and is fitted to the inner peripheral portion of the fixed frame 2 so as to be able to rotate and retreat. A cam follower and a gear portion 3a that meshes with the long gear are arranged on the outer peripheral rear portion. The rotating frame 3 is mounted with the cam follower engaged with the helicoid portion of the fixed frame 2 and is rotationally driven by the long gear via the gear portion 3a. The cam follower is slidably engaged with the circumferential groove in the extended state from the retracted position while rotating by the rotation, and then slidably engaged with the circumferential groove, and then rotated in the optical axis O direction to the tele position. Is done.

  The moving frame 4 is a cylindrical member, and is fitted into the inner peripheral portion of the rotating frame 3 so as to be relatively rotatable. The guide convex portion 4a is slidably fitted into the rectilinear groove 2c of the fixed frame 2 to be restricted in rotation. In this state (FIGS. 4 and 6), it is bayonet-coupled to the rotating frame 3, and is supported in a state of being capable of relative rotation and integrally moving forward and backward in the optical axis O direction.

  The rectilinear guide frame 6 is a cylindrical member and is fitted into the inner periphery of the moving frame 4. The rear end portion is bayonet-coupled to the cam frame 5, and advances and retreats together with the cam frame 5 in a state where rotation is restricted by the moving frame 4. Moving.

  The cam frame 5 is a cylindrical member, and is slidably fitted into the inner peripheral portion of the group zoom frame 7, and the rear end portion is fitted into the inner peripheral portion of the moving frame 4. As shown in FIG. 8, the cam follower 23 is fixed to the pin hole 5e at the outer peripheral rear portion of the cam frame 5 so as to protrude outward.

  As shown in FIG. 8, the cam follower 23 includes a conical surface portion 23a and a tip pin portion 23b. The conical surface portion 23a is fitted into a cam groove provided in the moving frame 4, and the tip pin portion 23b is inserted into the cam groove. Is inserted into a rectilinear groove provided in the rotary frame 3. Accordingly, the cam frame 5 is driven to advance and retract by the cam groove of the moving frame 4 in the direction of the optical axis O while rotating integrally with the rotating frame 3.

  A first group zoom frame driving cam groove 5a is arranged on the outer peripheral portion of the cam frame 5 (FIG. 8), and a second group zoom frame driving cam groove 5b and a third group zoom frame driving cam groove 5c are arranged on the inner peripheral portion. A retractable lens frame driving cam groove 5d, which is a cam groove, is provided (FIG. 9). The cam groove 5d has an open state on the back side, a rectilinear cam groove portion 5da formed on the opening side along the optical axis O direction, an inclined cam groove portion 5db inclined with respect to the optical axis O, and It consists of a relief cam groove 5dc along the rotation direction, and a projection 5dd that is provided in the rear opening of the cam groove 5d and protrudes rearward from the straight cam groove 5da. The cam groove portion is a cam groove having a gap with respect to a driven pin 12b of a retractable lens frame 12 (to be described later) to be engaged with the cam groove (FIGS. 9 and 15).

  The first group zoom frame 7 is a cylindrical member, and is fitted into the inner peripheral portion of the rectilinear guide frame 6 while being rotationally restricted, and is inserted into and supported by the outer peripheral portion of the cam frame 5. A first group lens 31 is held in the front opening of the first group zoom frame 7, and a lens barrier 35 that can open and close the front surface of the first group lens 31 is disposed. A cam follower provided so as to protrude from the inner peripheral portion of the first group zoom frame 7 is slidably fitted into the cam groove 5 a of the cam frame 5. Accordingly, the group zoom frame 7 is driven to advance and retract in a state in which the rotation is restricted by the linear guide frame 6 as the cam frame 5 rotates.

  The second group zoom frame 8 is a cylindrical member as shown in FIGS. 10 and 11, is slidably fitted into the inner periphery of the cam frame 5, and is supported by the center opening. . A guide convex portion 9f of the third group zoom frame 9 is slidably fitted in a guide groove 8b disposed on the outer periphery of the second group zoom frame 8, and further, a cam follower 8c disposed on the outer periphery of the second group zoom frame 8. Is slidably fitted in the cam groove 5b of the cam frame 5 (FIG. 9). Accordingly, the second group zoom frame 8 is driven to advance and retreat with the rotation of the cam frame 5 in a state in which the rotation is restricted via the third group zoom frame 9 guided linearly.

  The second group zoom frame 8 is provided with a retracting cam 8d, which is a protruding cam portion standing upright along the direction of the optical axis O, and a rotating shaft escape portion 8g facing the tip of the rotating shaft. As shown in FIGS. 10 and 11, the retracting cam 8d is disposed in a direction inclined at a predetermined angle from the center of the second group lens 32 (coincidence with the optical axis O) centering on the rotation shaft relief portion 8g as shown in FIGS. Is located. The predetermined angle is an angle at which a necessary rotation angle of the retractable lens frame 12 is obtained. The retracting cam 8d is provided with an inclined cam surface 8da and a parallel sliding surface 8db parallel to the direction of the optical axis O at the protruding tip portion.

  The third group zoom frame 9 is a cylindrical member as shown in FIGS. 12 and 13, and a light-shielding blade-like component is mounted on the front side, and the retractable lens frame 12 is rotatably supported inside the cylinder. In addition, a shutter unit 11 that is spring-biased behind the retractable lens frame 12 and is relatively movable back and forth in the direction of the optical axis O is disposed (FIGS. 2 and 3).

  The third group zoom frame 9 is provided with a cam follower 9b on the outer periphery of the cylindrical portion, a guide convex portion 9f on the inner peripheral portion, and a guide convex portion 9a on the outer periphery of the rear disk-shaped portion. Furthermore, a shaft support hole 9d for supporting both ends of the rotation shaft 25 is disposed inside the cylinder. Further, a central opening 9g through which the lens holding portion of the second group zoom frame 8 can be inserted, a retractable lens frame stopper 9c standing upright on the rear side, and a retracting cam insertion hole 9e are provided on the front end surface of the cylinder. The retractable lens frame 12 is rotatably supported by a rotation shaft 25 that is fitted into the shaft support hole 9d.

  The guide projection 9a of the third group zoom frame 9 is slidably fitted into the rectilinear groove 4b of the moving frame 4 (FIGS. 4 and 6), and the cam follower 9b is slidably fitted into the cam groove 5c of the cam frame 5. (FIG. 9). Therefore, the third group zoom frame 9 is driven to advance and retract as the cam frame 5 rotates while being restricted by the moving frame 4.

  The retractable lens frame 12 is a lever-shaped member as shown in FIG. 14, and has a shaft hole 12 a into which the rotation shaft 25 is rotatably fitted at one end portion, and a driven pin 12 b that is arranged to protrude in the vicinity of the shaft hole. A stopper abutting portion 12c and a driven abutting surface portion 12d are provided at the other end portion, and a retractable lens 33 having an optical axis O1 is held in an opening portion spaced a predetermined distance from the shaft hole 12a. The retractable lens frame 12 is urged clockwise in FIG. 12 by a torsion spring 26 that is an urging member.

  When the zoom lens barrel 1 is in the shooting state and no external force is applied to the retractable lens frame 12, the retractable lens frame 12 rotates clockwise about the rotation shaft 25 and comes into contact with the stopper. The portion 12c is in contact with the stopper 9c of the third group zoom frame 9, and the retractable lens 33 is in the photographing optical path. That is, the retractable lens frame 12 is located at the approach position P1 where the optical axis O1 of the retractable lens 33 coincides with the photographing lens optical axis O (FIG. 6).

  When the zoom lens barrel 1 is switched from the photographing state to the retracted state, the retractable lens frame 12 is first pressed with the driven pin 12b by the cam groove 5d as the cam frame 5 rotates, and is rotated a predetermined angle in the retracted direction. Move. Thereafter, the retracting lens frame 12 presses the driven contact surface portion 12d by the retracting cam 8d of the second group zoom frame 8 when the third group zoom frame 9 and the second group zoom frame 8 relatively approach in the optical axis O direction. Then, the retractable lens 33 is rotationally driven to the retracted position P2 retracted from the photographing optical path (FIG. 4). When switching from the retracted state to the photographing state, an operation opposite to the above-described operation is executed, and the retractable lens frame 12 is driven to rotate from the retracted position P2 to the entering position P1. The above-described rotation operation of the retractable lens frame 12 from the approach position P1 to the retracted position P2 will be described in detail later.

  The fourth group focus frame 13 is supported through a guide shaft so as to be movable back and forth in the direction of the optical axis O, and is driven forward and backward to the focusing position by the focusing unit during the focusing operation.

  The sensor unit support plate 16 is mounted on the back surface of the fixed frame 2 in a state of being displaceable in the XY direction after each frame member such as the rotating frame 3 is assembled in a state where the sensor unit 15 is assembled.

  The sensor unit 15 includes an optical filter 18 and an image sensor 19, and an XY drive unit 21 corrects the blur component of the image signal output from the image sensor 19 based on the camera shake detection signal during the blur correction process. The sensor unit support plate 16 and the sensor unit support plate 16 are driven to move in the XY directions.

  The advance / retreat operation of each lens frame member in the zoom lens barrel 1 having the above-described configuration will be described with reference to FIG. In the following description, it is assumed that the zoom lens barrel 1 is initially in the telephoto state of the photographing state, and then passes through the wide state (FIG. 6) of the photographing state to the retracted state (FIG. 4) of the non-photographing state. However, when moving from the retracted state to the photographing state, the reverse operation of the above-described retracting operation is executed.

  When the zoom lens barrel 1 is in the tele state, the cam followers (not shown) of the first group zoom frame 7 are in the tele corresponding position with respect to the cam grooves 5a, 5b, 5c of the cam frame 5. The cam followers 8c and 9b of the group zoom frame 9 are also positioned at the tele corresponding positions 8cT and 9bT (FIG. 9), and the respective frames are extended to the tele position. The retractable lens frame 12 supported by the third group zoom frame 9 is in contact with the stopper 9c by the urging force of the torsion spring 26 because the driven pin 12b is not engaged, and the retractable lens 33 enters the photographing optical path. It is located at position P1 (FIG. 6).

  When the tele state is switched to the wide state, the zoom frame 41 drives the cam frame 5 together with the rotating frame 3 counterclockwise, and the group frame zoom frame is moved with respect to the cam grooves 5a, 5b, 5c of the cam frame 5. 7 cam followers (not shown) move to the wide corresponding position, and the cam followers 8c and 9b of the second group zoom frame 8 and the third group zoom frame 9 also move to the wide corresponding positions 8cW and 9bW, respectively (FIG. 9). Each frame moves to the wide position. The retractable lens frame 12 is maintained at the approach position P1 as it is (FIG. 6).

  Subsequently, when the retracted state is retracted from the wide state, the cam frame 5 is also driven to rotate counterclockwise together with the rotating frame 3, and the rotating frame 3 is retracted to the retracted position. A cam follower (not shown) of the first group zoom frame 7 moves to a retractable position with respect to the cam grooves 5a, 5b, 5c of the cam frame 5, and a cam follower 8c of the second group zoom frame 8 and the third group zoom frame 9 9b also move to the wide corresponding positions 8cC and 9bC (FIG. 9), and the respective frames are brought into the retracted position (FIG. 2). During the switching operation from the wide state to the retracted state, the retractable lens frame 12 is rotationally driven by the cam groove 5d of the cam frame 5, and subsequently rotated by the protruding retractable cam 8d of the second group zoom frame 8. It is driven to move from the entry position P1 to the retreat position P2 as described above (FIG. 6).

  In the retracted state of the zoom lens barrel 1, as shown in FIG. 2, the rotating frame 3, the moving frame 4, the rectilinear guide frame 6, and the cam frame 5 are accommodated inside the fixed frame 2, and further, the group zoom frame 7. The second group zoom frame 8, the third group zoom frame 9, and the fourth group focus frame 13 are housed with a very small gap in the optical axis O direction. On the other hand, the retractable lens frame 12 is rotated to the retracted position P2 where the retractable lens 33 is retracted from the photographing optical path, and the zoom lens barrel is moved by bringing the third lens group 33 and the fourth lens group 34 as close as possible. Further shortening of the overall length in the direction of the optical axis O in the retracted state of 1 is possible.

  Here, the retracting operation of the retracting lens frame 12 of the third group zoom frame 9 will be described in detail with reference to FIGS.

  In the initial stage of the switching operation of the zoom lens barrel 1 from the wide state to the retracted state, if the cam frame 5 and the third group zoom frame 9 are relatively close due to the counterclockwise rotation of the cam frame 5, the wide corresponding position 12bW (see FIG. 15), the driven pin 12b of the retractable lens frame 12 contacts the projection 5dd provided at the cam groove opening of the cam frame 5, and then enters the cam groove 5d to engage with the rectilinear cam groove 5da. .

  When the cam frame 5 further rotates, the driven pin 12b moves to the relative movement positions 12b1, 12b2, and 12b3 along the wall surface of the cam groove portion while being pressed by the rectilinear cam groove portion 5da (FIG. 15). By the pressing movement of the driven pin 12b, the retractable lens frame 12 rotates counterclockwise (upward in FIG. 6) against the urging force F0 (FIG. 16) of the torsion spring 26, and the stopper contact portion 12c becomes the stopper 9c. The movement from the entry position P1 (FIG. 6) to the retreat position P2 is started. The driven contact surface portion 12d also moves counterclockwise from the wide corresponding position 12dW (FIG. 16).

  When the cam frame 5 continues to rotate, the driven pin 12b engages with the inclined cam groove portion 5db, moves to the relative movement position 12b4 while being pressed by the wall surface of the cam portion (FIG. 15), and the retractable lens frame 12 The counterclockwise rotation continues.

  During the rotating operation of the cam frame 5, the cam follower 8c of the second group zoom frame 8 and the cam follower 9b of the third group zoom frame 9 are moved to the moving positions 8c3 and 9b3 and the moving positions 8c6 on the cam grooves 5b and 5c of the cam frame 5, respectively. 9b6 (FIG. 15), the second group zoom frame 8 and the third group zoom frame 9 are close to each other. Accordingly, the retracting cam 8 d of the second group zoom frame 8 passes through the retracting cam insertion hole 9 e of the third group zoom frame 9 and enters the inside of the third group zoom frame 9. Therefore, the driven contact surface portion 12d of the retracting lens frame 12 that is rotating clockwise approaches the retracting cam 8d and contacts the inclined cam surface 8da of the retracting cam 8d. Thereafter, the retractable lens frame 12 shifts from the previous rotational driving state via the driven pin 12b by the cam groove 5d of the cam frame 5 to the rotational driving state via the driven contact surface portion 12d by the retracting cam 8d.

  When the rotation of the cam frame 5 further proceeds, the second group zoom frame 8 and the third group zoom frame 9 are relatively closer to each other, and the driven contact surface portion 12d is pressed by the inclined cam surface 8da to reach the relative movement position 12d5. (FIG. 16) The retractable lens frame 12 continues to rotate further counterclockwise. The driven pin 12b moves to the relative movement position 12b5 away from the wall surface of the inclined cam groove 5db by the pressing operation (FIG. 15).

  Further, when the second group zoom frame 8 and the third group zoom frame 9 are relatively close to each other, the driven contact surface portion 12d moves to the relative movement positions 12d6 and 12d7 on the parallel sliding surface 8db of the retracting cam 8d (FIG. 16). ), The retractable lens frame 12 reaches the retracted position P2 and is held at that position (FIG. 4). At this time, other lens frames such as the rotary frame 3 are also retracted to the retracted position, and the retracting operation of the zoom lens barrel 1 is completed. The driven pin 12b itself is kept in the disengaged state at the relative movement positions 12b6 and 12b7 and the wide corresponding position 12bC in the escape cam groove 5dc (FIG. 15).

  In the operation of switching the retractable lens frame 12 from the retracted state to the wide state of the zoom lens barrel 1, the reversing lens frame 12 is rotated in the reverse direction of the above-described operation, and the retraction position P2 (FIG. 4) is changed to the entry position P1 ( 6).

  In the zoom lens barrel 1 described above, the cam groove 5d of the cam frame 5 serves as the first half of the retraction drive from the entry position P1 to the retraction position P2 of the retraction lens frame 12 rotatably supported in the third group zoom frame 9. A sufficient rotation angle can be obtained by performing the two operations of driving by the above and the second half by driving by the retracting cam 8d provided on the second group frame 8, and the retracting lens frame 12 is positioned at a more desirable retracting position. It becomes possible. Further, since the latter half is driven by the retracting cam 8d away from the rotating shaft 25, the position accuracy of the retracted position P2 can be increased, and it is not necessary to take a large gap around the retracted retractable lens frame 12. The outer dimension of the frame can be further reduced.

  Further, the cam groove 5d provided on the inner peripheral portion of the cam frame 5 can be arranged without damaging the areas of the other cam grooves 5b and 5c by performing the retraction drive in two operations as described above, and the cam The driven pin 12 of the retractable lens frame 12 can be driven without difficulty by the groove 5d.

  Furthermore, unlike the conventional lens barrel A1, the retracting cam A14 is not provided on the back plate of the fixed frame A2, and the retracting cam 8d is arranged in the second group frame 8, so that the retracting lens frame is partially assembled in each lens frame. 12 evacuation operations can be confirmed, and assembly inspection and the like are facilitated. In the case of a lens barrel with a blur correction function as in this embodiment, there is no restriction due to the retracting cam with respect to the arrangement of the blur correction image sensor unit.

  The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention at the stage of implementation. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements.

  The zoom lens barrel according to the present invention is a zoom lens barrel having a retractable lens frame that is retracted in a non-photographing state, wherein the retracting mechanism of the retractable lens frame has an arrangement of cam grooves for moving the lens frame forward and backward and an arrangement of the imaging unit. It can be used as a zoom lens barrel that can be miniaturized without any restrictions.

2 ... fixed frame 5 ... cam frame (first frame)
5d: Retractable lens frame driving cam groove (cam groove portion)
8 ... Two-group zoom frame (second frame)
8d ... Retraction cam (cam part)
9 ... Three-group zoom frame (third frame)
12 ... Retracting lens frame 41 ... Unit storage section (zoom drive source) for storing long gears, etc.
P1 ... Entry position P2 ... Retraction position

Claims (1)

In a zoom lens barrel having a retractable lens frame that retracts in a non-shooting state,
A fixed frame,
Zoom drive source for zooming,
A first frame that is at least rotationally driven relative to the fixed frame by the zoom drive source and includes a cam groove;
A second frame that is driven forward and backward by the first frame and includes a cam portion;
A third frame driven forward and backward by the first frame;
A frame that is pivotally supported by the third frame, holds a retractable lens, and when in the photographing state, the retractable lens is in an entry position located on the optical path, and is from the photographing state. The retraction lens is revolved by the cam groove portion of the first frame and the cam portion provided on the second frame during the switching operation period to the non-photographing state, and the retraction lens is retreated out of the optical path. The retractable lens frame that is retracted to a position;
Equipped with,
The retractable lens frame is rotationally driven toward the retracted position by the cam groove portion of the first frame in the first half of the switching operation period from the shooting state to the non-shooting state, and in the second half, A zoom lens barrel , wherein the zoom lens barrel is rotationally driven by the cam portion provided on a second frame so as to be positioned at the retracted position .

Images