JP5122346B2 - Lens barrel - Google Patents

Description

  The present invention relates to a lens barrel, and more particularly, to a lens barrel housing structure including a retracting optical element that is retracted to a disengagement position that is decentered with respect to a photographing optical axis when the photographing is impossible.

In order to reduce the size of the camera, in particular, to reduce the thickness, a storage (collapse) type lens barrel that shortens the taking lens in a non-shooting state is required to further reduce the storage length. The applicant proposed the retractable lens barrel of Patent Document 1 as one of the means for solving the problem. In the lens barrel, the plurality of optical elements are positioned on the same photographing optical axis in the lens barrel member that accommodates the plurality of optical elements in the photographing state, and the plurality of optical elements are disposed in the retracted (contained) state. A part is retracted to an eccentric position from the photographing optical axis, and at least a part of the retracted optical element and at least a part of the optical element that is not retracted are independently retracted so that photographing is impossible. It is said.
Japanese Patent No. 3771909

  By the way, in a lens shutter type lens barrel, a shutter block having a diaphragm for adjusting the amount of light and a shutter is supported by a holding frame of the lens group and is often moved in the optical axis direction integrally with the lens group. . For example, in the embodiment of Patent Document 1, the optical element that can be retracted from the photographing optical axis is a lens group, and a shutter block is fixed to a support ring that holds the retracting lens group, and photographing is performed. The relative position of the shutter block and the retractable lens group in the optical axis direction did not change regardless of the state and the storage state. In Patent Document 1, in the retracted state in which photographing is not possible, the retractable lens group and the other lens group overlap in the optical axis direction position (overlapping in the direction orthogonal to the optical axis) to shorten the lens barrel storage length. However, the retractable lens group and the shutter block, which are supported by a common support ring and moved together during zooming operation, still have room for a compact storage state in the optical axis direction.

  Therefore, the present invention relates to a first optical element (retractable optical element) that is moved to a disengagement position from the optical axis when retracted with respect to a common support ring, and the first optical element and the optical axis direction during photographing. In a lens barrel that supports a second optical element positioned side by side, the space efficiency during storage is increased to make the lens barrel thinner, and the reliability and stability of the operation in the storage structure are ensured. The purpose is to do.

The lens barrel of the present invention holds a support ring that is moved backward in the optical axis direction when the imaging state is changed to the retracted state , a retracting optical element, and the retracting optical element is positioned at a capturing position on the capturing optical axis. A first holding member that is supported in a support ring so as to be movable to an insertion holding position to be moved and a detachment holding position at which the retracting optical element is positioned at a detaching position that is decentered with respect to the photographing optical axis ; supporting a second holding member that is supported so as to be moved in the optical axis direction in the support ring, to hold the first holding member in the insertion holding position in the photographing state, and disable the imaging from the photographing state storage An insertion / removal control means for moving the first holding member to the disengagement holding position by the backward movement of the support ring when entering the state, and in the photographing state, the advancing / retreating optical element at the rear in the optical axis direction of the retracting optical element at the photographing position. is located, in the stored state, it is in the disengaged position As at least a part of the optical axis direction position of避光Science element and reciprocating optical element overlaps a forward and backward control means for varying the optical axis direction position of the second holding member in the support ring by a retracting movement of the support ring, Provided on the first holding member and the second holding member, the first holding member is moved from the separation holding position to the insertion holding position independently of the insertion / removal control means at the time of transition from the housed state to the photographing state. A disengagement position maintaining means for restricting the movement and a support ring provided between the first holding member and the second holding member and abutting during the transition from the photographing state to the retracted state in the support ring by the advance / retreat control means A separation assisting section for applying a movement force in the direction of the separation holding position to the first holding member separately from the insertion / removal control means based on the movement force in the optical axis direction of the second holding member. Yes.

The second holding member may be configured to include a storage unit on the rearward extension of the retracting optical element in the optical axis direction so that the retracting optical element enters the storage unit in the stored state. In this case, disengaged position maintaining means, when the first holding member and the second holding member is in a relative position in the optical axis direction to store the saving optical element storage portion, to insert the holding position from the disengaged holding position The movement of the first holding member is restricted.

The first holding member can be moved to the insertion holding position and the separation insertion holding position by swinging about an axis parallel to the photographing optical axis. In this case, the disengagement position maintaining means is opposed to the rotation direction around the swing axis of the first holding member formed on one and the other of the first and second holding members and It is good to comprise as a pair of rotation control surface which makes a substantially parallel with an axis line.

Interpolation deregulation means includes a biasing member for biasing the first holding member in the insertion holding position direction is provided at the rear of the fixing member engages the retaining member of the first during retraction movement of the support ring It is preferable that a separation guide portion that generates a moving component force in the direction of the separation holding position against the urging member is provided.

  The present invention does not matter what kind of optical element is held in the support ring. For example, the retracting optical element can be a lens group, and the advancing / retracting optical element can be a light amount adjusting member that changes the aperture diameter of the photographing aperture.

  INDUSTRIAL APPLICABILITY The present invention is suitable for a zoom lens barrel having a variable focal length, and the retracting optical element and the advancing / retreating optical element move integrally in the optical axis direction at a constant interval in the optical axis direction during zooming operation in the shooting state. It is good to have a relationship.

  As described above, according to the present invention, the retracting optical element that is moved to the disengagement position from the optical axis when the lens barrel is housed, and the advance / retreat that is controlled to move at a fixed optical axis interval from the retracting optical element during photographing. In a lens barrel having an optical element, the first holding member that holds the retracting optical element and the forward / backward optical element are held while increasing the space efficiency during storage to reduce the storage length of the lens barrel. The mutual interference of the two holding members can be prevented, and the reliability and stability of the operation in the storage structure can be obtained.

  First, an overall structure of a retractable zoom lens barrel 1 to which the present invention is applied will be described mainly with reference to FIGS. 1 and 2 show a cross section of the zoom lens barrel 1. FIG. 1 is a storage state in which shooting is not performed, the upper half section of FIG. 2 is the wide end of the zoom shooting area, and the lower half section of FIG. Each edge is shown. 3 to 6 are exploded perspective views of the main part of the zoom lens barrel 1.

  The zoom lens barrel 1 includes, in order from the object side, a first lens group LG1, a second lens group (retractable optical element) LG2, a shutter S and an aperture A (advance / retract optical element, light amount adjusting member), a third lens group LG3, and a filter. 28 and a three-group optical system including a CCD (imaging device) 24. This optical system is a zoom optical system having a variable focal length, and zooming is performed by moving the first lens group LG1 and the second lens group LG2 along a predetermined locus along the optical axis (photographing optical axis) O of the optical system. Do. Further, focusing is performed by moving the third lens group LG3 along the optical axis O.

  Of the optical elements constituting the optical system of the zoom lens barrel 1, the filter 28 and the CCD 24 are held by a CCD support plate (advance / retreat control means, rear fixed member) 23. The first lens group LG1 to the third lens group LG3 are supported inside the lens barrel housing 11 fixed to the front portion of the CCD support plate 23.

  As shown in FIG. 3, the third group lens frame (advance / retreat control means) 7 that holds the third lens group LG3 is connected to the lens barrel housing 11 with respect to the guide hole formed through the cylindrical advance / retreat guide portion 7a. A third group guide shaft 22 fixed between the CCD support plates 23 is slidably inserted so as to be guided in a straight line so as to be movable in a direction parallel to the optical axis O, and is driven by the driving force of the AF motor 31. Can move forward and backward in the direction. More specifically, the AF motor 31 rotates a feed screw 31a, and an AF nut 31b is screwed to the feed screw 31a. The AF nut 31b is prevented from rotating by the engagement relationship with the guide protrusion 7b provided on the third group lens frame 7, and moves forward and backward in a direction parallel to the optical axis O when the feed screw 31a is rotated forward and backward. . The third group lens frame 7 is urged to move forward in the optical axis direction by a third group urging spring 39 formed of a tension spring stretched between the lens barrel housing 11 and the movement control plate 7c. Is brought into contact with the AF nut 31b. Therefore, when the AF nut 31b is moved forward in the optical axis direction, the third group lens frame 7 is moved forward by the biasing force of the third group biasing spring 39, and the AF nut 31b is moved rearward in the optical axis direction. Then, the movement control plate 7c is pushed against the urging force of the third group urging spring 39, and the third group lens frame 7 is moved rearward.

  A helicoid ring 12 is supported inside the lens barrel housing 11. A gear 12 a that meshes with the zoom gear 21 is formed on the outer peripheral surface of the helicoid ring 12, and the zoom gear 21 is rotationally driven by the zoom motor 30 shown in FIG. 3 to transmit the rotational force to the helicoid ring 12. The lens barrel housing 11 and the helicoid ring 12 are helicoidally coupled between the retracted (collapsed) state of FIG. 1 and the wide end of the upper half section of FIG. 2, and when the zoom motor 30 is driven, The helicoid ring 12 moves in the direction of the optical axis while rotating by the guide of the inner surface helicoid 11a. On the other hand, when the photographing state is between the wide end and the tele end, the helicoid coupling is released, and instead provided on the outer surface of the helicoid ring 12 with respect to the circumferential groove 11b formed on the inner peripheral surface of the lens barrel housing 11. The protrusion 12b is engaged, and the helicoid ring 12 is rotated at a fixed position without moving in the optical axis direction in accordance with the driving of the zoom motor 30. The front part of the helicoid ring 12 is coupled to a first feeding cylinder 13 that rotates and moves in the optical axis direction together with the helicoid ring 12.

  A linear guide ring 14 is supported inside the first feeding cylinder 13 and the helicoid ring 12. The rectilinear guide ring 14 is guided rectilinearly in the optical axis direction by the engagement relationship between the linear groove 11 c formed on the inner peripheral surface of the lens barrel housing 11 and the rectilinear guide protrusion 14 a, and the first feed cylinder 13 and the helicoid ring 12 Is engaged so that it can move in the optical axis direction.

  As shown in FIG. 4, the linear guide ring 14 has a through guide groove 14 b penetrating the inner peripheral surface and the outer peripheral surface. The penetrating guide groove 14 b has a lead groove portion that is inclined with respect to the optical axis O and a circumferential groove portion that surrounds the optical axis O, and an outer diameter protrusion 17 a provided on the outer peripheral surface of the cam ring 17. It fits slidably. The outer diameter protrusion 17 a is further engaged with a rotation transmission groove 13 a parallel to the optical axis O formed on the inner peripheral surface of the first feeding cylinder 13, and the cam ring 17 is rotated together with the first feeding cylinder 13. When the outer diameter protrusion 17a is engaged with the lead groove portion of the penetrating guide groove 14b, the cam ring 17 receives light from the first groove 13 and the rectilinear guide ring 14 while rotating under the guidance of the lead groove portion. When the outer diameter protrusion 17a is engaged with the circumferential groove portion of the through guide groove 14b and is moved forward and backward in the axial direction, it does not move relative to the first feed cylinder 13 and the linear guide ring 14 in the optical axis direction. Rotate with. Similar to the helicoid ring 12, the cam ring 17 is moved forward and backward in the optical axis direction while rotating between the retracted (collapsed) state and the photographing state, and the cam ring 17 is fixed in the photographing state between the wide end and the tele end. It is rotated.

  Linear grooves 14 c and 14 d parallel to the optical axis O are formed on the inner peripheral surface of the rectilinear guide ring 14. A rectilinear guide protrusion 18a of the second rectilinear guide ring 18 is slidably engaged with the linear groove 14c, and a rectilinear guide protrusion 16a of the second feed cylinder 16 is slidably engaged with the linear groove 14d. Due to the engagement relationship between the straight groove and the straight guide protrusion, the second straight guide ring 18 and the second feed cylinder 16 are guided in the straight direction in the optical axis direction. The second rectilinear guide ring 18 and the second feeding cylinder 16 are supported so as to be rotatable relative to the cam ring 17 and move integrally in the optical axis direction.

  The second rectilinear guide ring 18 linearly moves the second group lens moving frame (support ring) 8 in the optical axis direction by slidably engaging the three rectilinear guide keys 18b projected forward with the linear groove 8a. invite. A second lens group LG <b> 2 is supported inside the second group lens moving frame 8 via the second group lens frame 6. Further, a linear groove 16b parallel to the optical axis O is formed on the inner peripheral surface of the second feeding cylinder 16, and the straight guide protrusion 19a of the third feeding cylinder 19 is slidably engaged with the linear groove 16b. The third feeding cylinder 19 is also guided in a straight line in the optical axis direction. The first lens group LG <b> 1 is supported inside the third feeding cylinder 19 via the first group support ring 5 and the first group lens frame 4.

  The second group cam follower 8 b provided on the outer peripheral surface of the second group lens moving frame 8 is engaged with the second group control cam groove 17 b formed on the inner peripheral surface of the cam ring 17. Since the second group lens moving frame 8 is linearly guided in the optical axis direction via the second straight guide ring 18, when the cam ring 17 rotates, the second group lens moving frame 8 follows the shape of the second group control cam groove 17 b. That is, the second lens group LG2 moves along a predetermined locus in the optical axis direction.

  The third feeding cylinder 19 has a first group cam follower 19b protruding in the inner diameter direction, and this first group cam follower 19b is slidably fitted in a first group control cam groove 17c formed on the outer peripheral surface of the cam ring 17. doing. Since the third feeding cylinder 19 is guided linearly in the optical axis direction via the second feeding cylinder 16, when the cam ring 17 rotates, the third feeding cylinder 19, that is, the first feeding cylinder 19 according to the shape of the first group control cam groove 17c. The lens group LG1 moves along a predetermined locus in the optical axis direction.

  A pair of group biasing springs 32 shown in FIG. 5 are stretched between the second group lens moving frame 8 and the third feeding cylinder 19. The group biasing spring 32 biases the second group lens moving frame 8 and the third feeding cylinder 19 toward each other, and between the second group control cam groove 17b and the second group cam follower 8b, and 1 Backlash between the group cam follower 19b and the first group control cam groove 17c is taken to improve the fitting accuracy.

  In the zoom lens barrel 1 described above, with respect to the optical elements such as the second lens group LG2, the shutter S, and the aperture stop A that are supported by the second group lens moving frame 8, the space efficiency at the time of housing the barrel is improved and the thickness of the barrel is reduced. Is realized. Hereinafter, the detailed structure will be described.

  As shown in FIG. 5, the second group lens moving frame 8 is formed with an inner diameter flange portion 8c on the front end side, and a pressing plate 38 is provided at a rear position facing the inner diameter flange portion 8c. . The holding plate 38 is formed with a pair of shaft support holes 38a and 38b. The inner diameter flange portion 8c has a shaft support hole (not shown) facing the shaft support hole 38a and a shaft facing the shaft support hole 38b. Support holes 8h (FIGS. 17 to 21) are formed. The periphery of the shaft support hole 38b of the pressing plate 38 is a movement restricting recess 38d that is lowered by one step toward the rear in the optical axis direction. One end portion and the other end portion of the second group frame swing shaft 35 are inserted and supported in one shaft support hole 38a of the pressing plate 38 and the shaft support hole on the inner diameter flange portion 8c opposite thereto. One end portion and the other end portion of the shutter guide shaft 36 are inserted and supported in the other shaft support hole 38b of the pressing plate 38 and the shaft support hole 8h of the inner diameter flange portion 8c opposed thereto. In this support state, the axial directions of the second group frame swing shaft 35 and the shutter guide shaft 36 are substantially parallel to the optical axis O.

  As shown in FIGS. 8 and 9, the second group lens frame (first holding member) 6 includes a lens cylinder 6a on which the second lens group LG2 is mounted, and a swing arm extending in the radial direction of the lens cylinder 6a. 6b, and a swing center tube 6c provided at the tip of the swing arm 6b and having an axis line substantially parallel to the optical axis O. A shaft hole penetratingly formed in the center of the swing center tube 6c is rotatably supported by the second group frame swing shaft 35. The front and rear end portions of the swing center tube 6c are sandwiched between the inner diameter flange portion 8c of the second group lens moving frame 8 and the pressing plate 38, and the movement is restricted. The second group lens frame 6 is urged forward in the optical axis direction by a second group frame urging spring 34 (compression coil spring) disposed between the intermediate flange portion 6d on the swinging center tube 6c and the pressing plate 38. The second group lens moving frame 8 is held at a certain position in the optical axis direction.

The second lens group LG2 fixed to the lens cylinder 6a moves on the optical axis O by the swinging movement of the second group lens frame 6 around the second group frame swinging shaft 35 in the second group lens moving frame 8. 2 (the optical axis of the second lens group LG2 coincides with the optical axis O of the entire optical system) (FIG. 2, FIG. 14, FIG. 16, FIG. 20, FIG. 21) The optical axis is moved in a plane perpendicular to the optical axis O between the optical axis separation positions (FIGS. 1, 10 to 13, FIG. 15, and FIGS. 17 to 19) retracted in the eccentric region. The position of the second group lens frame 6 that positions the second lens group LG2 at the photographing position is defined as the insertion holding position, and the position of the second group lens frame 6 that positions the second lens group LG2 at the optical axis separation position is defined as the separation holding position. The second group lens frame 6 has a stopper arm that abuts against a stopper 8g (FIGS. 5 and 10) provided in the second group lens moving frame 8 when the second group lens frame 6 moves to the insertion holding position. 6e is provided.

A second group frame return spring (insertion / removal control means, urging member) 33 is supported on the outer surface of the swing center tube 6 c of the second group lens frame 6. The second group frame return spring 33 is formed of a torsion spring having a coil portion surrounding the swinging central cylinder 6c and a pair of spring end portions extended from the coil portion, and one spring end portion is set as the second group lens frame. 6 is engaged in the vicinity of the swing arm 6b, and the other spring end is engaged with the spring hooking hole 8j (FIG. 10) of the second lens group moving frame 8. The second group frame return spring 33 urges the second group lens frame 6 to rotate toward the insertion holding position.

  The second group lens frame 6 is formed with a semicircular large-diameter cylindrical portion 6f that surrounds the outer side of the swinging central cylinder 6c, and a position control projection 6g extends from the large-diameter cylindrical portion 6f toward the outer radial direction. Projected. The rear end portion of the position control projection 6g is a rear end inclined surface 6h that is an inclined surface with respect to a plane orthogonal to the optical axis O. The CCD support plate 23 is formed with a second group detachment control protrusion (insertion / removal control means, detachment guide portion) 23a that engages with the position control protrusion 6g to control the position of the second group lens frame 6. The second group separation control projection 23a is projected forward in the optical axis direction in the vicinity of the support position of the CCD 24 on the CCD support plate 23, and has a transition inclined surface (cam surface) 23b at the tip. . The transition inclined surface 23b is inclined so as to gradually increase the amount of forward protrusion in the optical axis direction as the distance from the central portion of the CCD support plate 23 that supports the CCD 24 increases. A side surface 23c of the second group separation control protrusion 23a following the transition inclined surface 23b is a surface parallel to the optical axis O. The holding plate 38 has a protrusion insertion hole 38c that allows the second group separation control protrusion 23a to pass therethrough.

The second group lens frame 6 is held at the aforementioned insertion holding position by the urging force of the second group frame return spring 33 in a state where no external force is input to the position control protrusion 6g. When the second group lens frame 6 approaches the CCD support plate 23 as the second group lens moving frame 8 moves, the second group separation control projection 23a approaches the position control projection 6g through the projection insertion hole 38c, and the rear end inclined surface. The transition inclined surface 23b comes into contact with 6h. Then, a rotational force component is generated from the moving force in the optical axis direction, and the second group lens frame 6 is rotated toward the above-described detachment holding position against the urging force of the second group frame return spring 33. In this retracted state, a part of the second group lens frame 6 enters a notch 8d (FIGS. 5 and 10) formed through the inner and outer peripheral surfaces of the second group lens moving frame 8. It does not protrude outside the group lens moving frame 8 and does not interfere with the cam ring 17 located outside the second group lens moving frame 8.

  The second group lens moving frame 8 is formed with a pair of spring housing portions 8e and 8f for inserting the pair of intergroup biasing springs 32 at positions where the second group lens frame 6 does not interfere with the space where the second group lens frame 6 swings. Yes. The presser plate 38 is formed with a spring insertion hole 38e positioned on the extension of the spring accommodating portion 8e. The pair of group urging springs 32 are each formed of a tension spring, and are inserted into the corresponding spring storage portions 8e and spring insertion holes 38e and the spring storage portions 8e and 8f, respectively. One spring end is hung on a spring hook (not shown) provided at the rear. The other spring end of the intergroup biasing spring 32 extends forward from the second group lens moving frame 8 and is hooked on a spring hook 19c (FIG. 6) provided on the third feeding cylinder 19.

  In addition to the second group lens frame 6, a shutter member (second holding member) 10 having a shutter S and an aperture A is provided in the second group lens moving frame 8 via a shutter support ring (second holding member) 9. It is supported. As shown in FIG. 5, the shutter member 10 has a shutter opening (photographing opening) 10a whose opening is changed by the shutter S and the diaphragm A, and the shutter S and the diaphragm are housed in a housing surrounding the shutter opening 10a. An actuator for driving A is incorporated. Extending from the shutter member 10 is a flexible substrate 10b for sending an operation signal to the actuator.

On the outer periphery of the shutter member 10, a stepped side notch 10 c is formed that has a shape that avoids interference with the vicinity of the swing center tube 6 c of the second group lens frame 6 and the pressing plate 38. The side notch portion 10c includes an upper notch portion 10c1 at a position corresponding to the spring accommodating portion 8e of the second group lens moving frame 8 and the spring insertion hole 38e of the pressing plate 38, and an intermediate notch located on the extension of the shutter guide shaft 36. It is roughly divided into a portion 10c2 and a lower cutout portion 10c3 located on the extension of the second group frame swing shaft 35. The lower cutout portion 10c3 has a semicircular cutout shape having a larger diameter than the large diameter cylindrical portion 6f of the second group lens frame 6. The outer peripheral portion of the shutter member 10 further includes a semicircular lower concave portion 10d at a position corresponding to the lens barrel 6a of the second group lens frame 6 in the above-described detachment holding position, and a spring storage portion 8f of the second group lens moving frame 8. Side cutouts 10e are formed at positions corresponding to.

  As shown in FIGS. 5 and 7, the shutter support ring 9 that supports the shutter member 10 has a front flange portion 9a with which the front surface portion of the shutter member 10 abuts, and a shutter opening portion 10a at the center of the front flange portion 9a. A larger-diameter front opening 9b is formed. A front end annular rib 9c protruding forward in the optical axis direction is formed around the front opening 9b. A partial cylindrical surface 9d is formed along the inner peripheral surface of the second group lens moving frame 8 from the periphery of the front flange portion 9a toward the rear in the optical axis direction. A first notch 9e, a second notch 9f, a second group storage recess (storage) 9g, and a third notch 9h are formed on the periphery of the shutter support ring 9 in a manner in which a part of the partial cylindrical surface 9d is cut away. Is formed. The second cutout portion 9f has a semicircular cutout shape having a larger diameter than the large diameter cylindrical portion 6f of the second group lens frame 6. Between the first notch portion 9e and the second notch portion 9f, there is provided a movement restricting plate 9i located behind the front flange portion 9a in the optical axis direction, from the movement restricting plate 9i toward the front in the optical axis direction. A cylindrical advance / retreat support cylinder 9j is projected. The movement restricting plate 9i and the front flange portion 9a are connected by a semi-cylindrical connection wall 9r surrounding the advance / retreat support tube 9j.

  When the shutter member 10 is assembled to the shutter support ring 9, two positioning bosses 10 f provided on the front surface portion of the shutter member 10 are inserted into the two boss engagement holes 9 k formed in the front flange portion 9 a of the shutter support ring 9. The three positioning protrusions 10g provided on the outer peripheral surface of the shutter member 10 are engaged with the three protrusion engaging holes 9m formed on the partial cylindrical surface 9d of the shutter support ring 9. When the shutter member 10 is assembled to the shutter support ring 9 in this way, the lower concave portion 10d is fitted to the back side (the rear side in the optical axis direction) of the second group storage concave portion 9g. Further, the first cutout portion 9e and the upper cutout portion 10c1, the second cutout portion 9f and the lower cutout portion 10c3, the third cutout portion 9h and the side cutout portion 10e are aligned in a direction parallel to the optical axis O, respectively. It becomes a notch. The connection wall 9r of the shutter support ring 9 is located along the intermediate notch 10c2 of the shutter member 10.

  A shutter guide shaft 36 is slidably inserted into a guide hole formed through the center of the advancing / retracting support cylinder 9j, and a combined body of the shutter member 10 and the shutter support ring 9 is guided by the shutter guide shaft 36. A shutter block SB is supported in the second group lens moving frame 8 so as to be movable in the direction along the optical axis O. Further, a rail-like portion 8i (FIG. 5) having a uniform cross-sectional shape in the optical axis direction is formed on the inner peripheral portion of the spring housing portion 8f in the second group lens moving frame 8, and the rail-like portion 8i On the other hand, when the third cutout portion 9h of the shutter support ring 9 and a part of the side cutout portion 10e of the shutter member 10 are slidably fitted in the optical axis direction, the shutter block SB is moved to the second group lens moving frame 8. Against rotation.

  In a state where the shutter block SB is supported by the second group lens moving frame 8, a shutter made of a compression coil spring is provided between the movement restricting plate 9i of the shutter support ring 9 and the inner diameter flange portion 8c of the second group lens moving frame 8. A push spring (advance / retreat control means) 37 is inserted. As shown in FIGS. 17 to 21, the shutter pressing spring 37 is accommodated in a radial space between the shutter guide shaft 36 and the connection wall 9r. By this shutter pressing spring 37, the shutter support ring 9 is urged to move rearward in the optical axis direction with respect to the second group lens moving frame 8. The rearward movement end of the shutter block SB within the second lens group moving frame 8 is determined by the movement restriction plate 9 i of the shutter support ring 9 coming into contact with the movement restriction recess 38 d of the pressing plate 38. The contact surfaces of the movement restricting plate 9i and the movement restricting recess 38d are flat surfaces that are substantially orthogonal to the optical axis O.

  The second cutout portion 9f and the lower cutout portion 10c3 are large-diameter cylinders of the second group lens frame 6, particularly the swing center tube 6c, when the shutter block SB changes the position in the optical axis direction within the second group lens moving frame 8. It functions as an escape portion that prevents interference with the portion 6f. The first notch 9e and the upper notch 10c1, and the third notch 9h and the side notch 10e are respectively 2 when the shutter block SB changes the position in the optical axis direction within the second group lens moving frame 8. It functions as an escape portion for preventing interference with the spring housing portions 8e and 8f of the group lens moving frame 8. As described above, the third cutout portion 9h and the side cutout portion 10e also have a function of restricting the rotation of the shutter block SB by the sliding contact relationship with the rail-like portion 8i on the back surface side of the spring storage portion 8f.

  As shown in FIGS. 15 and 16, the second notch 9f of the shutter support ring 9 has a shape along the outer peripheral surface of the large-diameter cylindrical portion 6f of the second group lens frame 6, and the second notch 9f An escape recess 9n that prevents interference with the position control projection 6g of the second group lens frame 6 is formed on the upper end side. Further, in the shutter support ring 9, a portion that is adjacent to the lower end of the second notch 9 f is provided with a rotation restricting surface (detachment position maintaining means) 9 p that is long in the optical axis direction. The rotation restricting surface 9p is a plane parallel to the optical axis O and directed in the radial direction (radial direction) about the second group frame swing shaft 35 (see FIGS. 15 and 16).

  From the large-diameter cylindrical portion 6f of the second group lens frame 6, the position is different from the position control projection 6g for engagement with the second group separation control projection 23a, and the rotation regulating projection (detachment position) is directed toward the outer diameter direction. Maintenance means) 6i is projected. As shown in FIG. 9, a rotation regulating surface 6j that is long in the optical axis direction is formed on one side surface of the rotation regulating projection 6i. The rotation restricting surface 6j is a plane parallel to the optical axis O and directed in the radial direction (radial direction) about the second group frame swing shaft 35 (see FIGS. 15 and 16). An inclined surface portion (detachment assisting portion) 6k that is inclined with respect to the optical axis O is formed between the rear end portion of the rotation restriction projection 6i and the rotation restriction surface 6j.

  The zoom lens barrel 1 having the above structure operates as follows. When the main switch provided in the camera is turned on in the lens barrel storage state shown in FIG. 1, the zoom motor 30 is driven in the lens barrel feeding direction. The zoom gear 21 is rotationally driven by the zoom motor 30, and the helicoid ring 12 and the first feeding cylinder 13 are guided by the inner surface helicoid 11a of the lens barrel housing 11 and rotated forward. The straight guide ring 14 moves straight forward together with the first feeding cylinder 13 and the helicoid ring 12. At this time, the cam ring 17 to which the rotational force is applied from the first feeding cylinder 13 has a lead structure (penetration guide groove) provided between the linear movement of the linear guide ring 14 forward and the linear guide ring 14. The combined movement of the lead groove portion of 14b and the feeding portion by the outer diameter projection 17a) is performed. When the helicoid ring 12 and the cam ring 17 are drawn out to a predetermined position in front, the functions of the respective rotary feeding structures (helicoid, lead) are released, and only rotation is performed at a fixed position in the optical axis direction.

  When the cam ring 17 rotates, on the inner side, the second group lens moving frame 8 guided by the second straight guide ring 18 moves in the optical axis direction due to the relationship between the second group cam follower 8b and the second group control cam groove 17b. Is moved along a predetermined trajectory. Further, when the cam ring 17 rotates, the third feeding cylinder 19 guided linearly through the second feeding cylinder 16 on the outside of the cam ring 17 is related to the first group cam follower 19b and the first group control cam groove 17c. Is moved along a predetermined locus in the optical axis direction.

  That is, the first lens group LG1 and the second lens group LG2 are fed out from the lens barrel retracted state by the former moving amount of the cam ring 17 with respect to the lens barrel housing 11 and the third extension with respect to the cam ring 17, respectively. The sum is determined as a sum of the cam feed amount of the cylinder 19 and the latter is a sum of the amount of forward movement of the cam ring 17 relative to the barrel housing 11 and the cam feed amount of the second group lens moving frame 8 relative to the cam ring 17. Determined. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 on the photographing optical axis O while changing the air interval between them. When the lens barrel is extended from the housed state of FIG. 1, first, the wide end extended state shown in the upper half cross section of FIG. 2 is obtained, and when the zoom motor 30 is further driven in the lens barrel extending direction, the lower half cross section of FIG. As shown in FIG. In the zoom region between the tele end and the wide end, the helicoid ring 12, the first feeding cylinder 13, and the cam ring 17 perform only the above-mentioned fixed position rotation, and do not advance or retreat in the optical axis direction. When the main switch is turned off, the zoom motor 30 is driven in the lens barrel storing direction, and the zoom lens barrel 1 performs a retracting operation opposite to the above-described feeding operation, resulting in the retracted state of FIG.

  Further, when the photographing from the wide end to the tele end is possible, the third group lens frame that supports the third lens group LG3 by driving the AF motor 31 according to the subject distance information obtained by the distance measuring means. 7 is moved along the optical axis O to perform focusing.

  The above is the overall operation of the zoom lens barrel 1, and then the operation of the storage structure centering on the relationship between the second lens group LG2 and the shutter block SB along the time series shown in FIGS. Will be explained. In FIG. 17 to FIG. 21, a plurality of elements that do not exist on the same cross section are shown on one drawing for easy understanding, and in detail, a position passing through the optical axis O shown in the lower part of the drawing. In addition to the cross section of FIG. 5, the cross section near the shutter guide shaft 36, the positional relationship of the second group separation control protrusion 23a with respect to the position control protrusion 6g of the second group lens frame 6, and the shutter with respect to the rotation restricting protrusion 6i of the second group lens frame 6. The positional relationship of the rotation restricting surface 9p of the support ring 9 is shown at the same time. In FIG. 17 to FIG. 21, a two-dot chain line Q1 is a position in the optical axis direction on the front surface of the inner diameter flange portion 8c of the second group lens moving frame 8, and a two-dot chain line Q2 is a position in the optical axis direction on the front surface of the front flange portion 9a of the shutter support ring 9. The two-dot chain line Q3 means a reference plane on the CCD support plate 23. The reference surface Q3 is a fixed surface position that is not moved by a zooming operation or a focusing operation of the zoom lens barrel 1.

FIG. 17 corresponds to the lens barrel storage state of FIG. 1, and the third group lens frame 7 is retracted to the rearward moving end that contacts the front portion of the CCD support plate 23. The rear surface of the shutter member 10 constituting the shutter block SB is in contact with the front surface portion of the third group lens frame 7, and the further backward movement of the shutter block SB is restricted. The second group lens moving frame 8 is further retracted against the urging force of the shutter pressing spring 37 with respect to the shutter block SB whose retreat is restricted, and the inner diameter flange portion 8c (Q1) while compressing the shutter pressing spring 37. ) Is brought close to the front flange portion 9a (Q2) of the shutter support ring 9. At this time, as shown in FIGS. 15 and 17, the second group lens frame 6 moves the second lens group LG2 from the optical axis O by the contact relationship between the position control projection 6g and the side surface 23c of the second group separation control projection 23a. is held in the disengaged holding position is disengaged downward, FIG. 10, as represented in FIGS. 11 and 12, the lens barrel 6a for holding the second lens group LG2, 2 groups of the shutter support ring 9 It is stored in the storage recess 9g.

The second group lens frame 6 is urged to rotate in the clockwise direction of FIG. 15 by the second group frame return spring 33. This is because the position control projection 6g contacts the side surface 23c of the second group separation control projection 23a. The rotation of the second group lens frame 6 in the urging direction is restricted. At the same time, in the rotation direction of the second group lens frame 6, the rotation restricting surface 6j of the rotation restricting projection 6i faces the rotation restricting surface 9p of the shutter support ring 9, and rotates with the rotation restricting surface 9p. The rotation of the second group lens frame 6 in the clockwise direction in FIG. 15 is also restricted by the contact relationship of the movement restricting surface 6j. That is, apart from the second group separation control projection 23a that controls the position of the second group lens frame 6, the second group lens frame 6 is also independently held at the separation holding position between the shutter block SB and the second group lens frame 6. A disengagement position maintaining means is provided.

  In the housed state of FIG. 17, the shutter S and the aperture stop A are located close to the third lens group LG3, and the optical axis direction positions of the shutter block SB and the third lens group LG3, and the optical axis of the second lens group LG2. Since the direction position overlaps (the second lens group LG2 overlaps the shutter block SB and the third lens group LG3 in a direction perpendicular to the optical axis O), the second lens group LG2 and the shutter S and The storage space in the optical axis direction occupied by the optical elements up to the third lens group LG3 across the stop A can be made extremely thin, and the storage length of the zoom lens barrel 1 is shortened. As shown in FIG. 1, in the lens barrel storage state, the rear surface of the first group lens frame 4 is retracted until it contacts the front end annular rib 9c of the shutter support ring 9, and the first lens group LG1 and the shutter block SB are retracted. The interval is also packed. The positions near the rear part of the first lens group LG1 and the vicinity of the front part of the second lens group LG2 also have a relationship in which the positions in the optical axis direction overlap (overlapping in a direction perpendicular to the optical axis O). That is, in the zoom lens barrel 1, the entire optical system from the first lens group LG1 closest to the object side to the CCD 24, which is the imaging unit, is housed in an extremely compact size in the optical axis direction.

  18 to 21 show the transition from the lens barrel storage state to the wide-end shooting state in FIG. 17 in time series. When the zoom lens barrel 1 is extended from the storage position of FIG. 1 by driving the zoom motor 30, the second group lens moving frame 8 is moved forward in the optical axis direction. Here, since there is room for the second group lens moving frame 8 to move forward relative to the shutter block SB, the second group lens moving frame 8 moves forward, but the shutter block SB is biased by the shutter pressing spring 37. The state of being pressed against the front surface of the third group lens frame 7 continues and is not moved in the optical axis direction. As a result, the interval between Q2 and Q3 does not change, and the interval between Q1 and Q2 increases. The second group lens frame 6 and the pressing plate 38 are also moved forward integrally with the second group lens moving frame 8, and the lens barrel 6 a of the second group lens frame 6 is moved into the second group storage recess 9 g of the shutter support ring 9 by this forward movement. Leave ahead. Further, the movement restricting recess 38 d of the pressing plate 38 approaches the movement restricting plate 9 i of the shutter support ring 9.

Expansion of the interval between Q1 and Q2 continues until the state of FIG. FIG. 18 shows a state in which the movement restricting concave portion 38d of the pressing plate 38 is abutted against the movement restricting plate 9i of the shutter support ring 9 as a result of the forward movement of the second group lens moving frame 8. When the second group lens moving frame 8 is moved forward to the position of FIG. 18, the lens cylinder 6a of the second group lens frame 6 is disengaged forward from the second group storage recess 9g of the shutter support ring 9 (see FIG. 13). . Further, the rear end portion of the rotation restricting projection 6i is positioned slightly forward of the front end portion of the turn restricting surface 9p (see FIG. 22), and the rotation restricting surface 9p and the rotation restricting surface 6j are brought into contact with each other. The rotation restriction of the second group lens frame 6 toward the insertion holding position is released.

Between FIG. 17 and FIG. 18, the state where the position control projection 6g is in contact with the side surface 23c of the second group separation control projection 23a continues, and apart from the rotation restriction by the rotation restriction surface 9p, the second group lens. The frame 6 is held at the separation holding position by the second group separation control projection 23a. However, if the rotation restriction by the second group separation control protrusion 23a is released before the state shown in FIG. 18 due to some mechanical error, the rotation restriction surface 6j of the rotation restriction protrusion 6i is turned. The rotation of the second group lens frame 6 to the insertion holding position is restricted by being applied to the restriction surface 9p. Since this rotation restricting surface 9p is formed in the shutter support ring 9 like the second group storage recess 9g, there is no room for mechanical error, and at least a part of the lens barrel 6a is also in the second group storage recess 9g. When in, the rotation of the second group lens frame 6 in the insertion holding position direction can be reliably restricted by the contact relationship between the rotation restricting surface 6j and the rotation restricting surface 9p. That is, while the second group lens frame 6 and the shutter support ring 9 are in a relative positional relationship in the optical axis direction that can cause mutual interference between the lens barrel 6a and the second group storage recess 9g, the rotation restriction projection 6i and the rotation restriction projection 6i. The surface 9p has a fail-safe structure that can hold the second group lens frame 6 in the detached holding position against the urging force of the second group frame return spring 33.

After the movement restricting plate 9i and the movement restricting recess 38d are engaged as shown in FIG. 18, the movement restricting plate 9i is pressed against the movement restricting recess 38d, whereby the second group lens moving frame 8 and the shutter block SB are integrated. Therefore, it is moved forward in the optical axis direction. That is, while Q1 and Q2 are kept at a constant interval, the interval between Q1 and Q3 and the interval between Q2 and Q3 are equally increased. FIG. 19 shows that the boundary portion between the rear end inclined surface 6h and the side surface portion of the position control projection 6g is located at the boundary portion between the transition inclined surface 23b and the side surface 23c in the second group separation control projection 23a as a result of increasing the interval between Q1 and Q3. It shows the state reached. At this time, when the rotation restriction by the side surface 23c of the second group separation control projection 23a with respect to the second group lens frame 6 is released and the second group lens moving frame 8 moves forward from the position of FIG. While the rear end inclined surface 6h of the position control projection 6g is slidably contacted with the transition inclined surface 23b of the second group separation control projection 23a by the force, the second group lens frame 6 rotates from the separation holding position to the insertion holding position. It will be moved. As described above, since the lens barrel 6a has already been detached forward from the second group storage recess 9g at the time of FIG. 18, the second group lens frame 6 interferes with the shutter support ring 9 to prevent rotation. Absent.

14 and 20 show a state in which the rotation of the second group lens frame 6 to the insertion holding position has been completed. The second lens group LG2 advanced on the optical axis O is positioned in front of the shutter block SB, and thereafter the optical axes of the second lens group LG2, the shutter S, and the aperture A until the lens barrel storage operation is performed again. The direction spacing is kept constant. Between FIG. 19 to FIG. 20 in which the second group lens frame 6 is rotated to the insertion holding position, the forward movement of the second group lens moving frame 8 and the shutter block SB is continued. While the interval is kept constant, the intervals between Q1 and Q3 and between Q2 and Q3 are increased.

Note that, in the lens barrel storage state of FIG. 17, the third group lens frame 7 is pushed in against the urging force of the third group urging spring 39 to the mechanical rearward movement end against the CCD support plate 23. This is the shutter block SB (strictly, the rear surface of the shutter member 10). At this time, the AF nut 31b is stopped at a position farther forward than the movement control plate 7c of the third group lens frame 7, and the stop position of the AF nut 31b is practically used (in terms of software). This is the rear moving end of the third group lens frame 7 to be controlled. Then, when the zoom lens barrel 1 is extended from the housed state and the shutter block SB is moved forward as shown in FIG. 18 and thereafter, the third group lens frame 7 also follows by the biasing force of the third group biasing spring 39. Moved forward. Then, during the period from the start of the rotation of the second group lens frame 6 shown in FIG. 19 to the insertion holding position until the completion of the rotation to the insertion holding position shown in FIG. 20, the movement control plate 7c contacts the AF nut 31b. The forward movement of the third group lens frame 7 is restricted. As a result, the distances between the second lens group LG2 and the shutter block SB that continue to move forward and the third lens group LG3 are increased.

When the second group lens moving frame 8 is advanced to the position shown in FIG. 21, the photographing state at the wide end shown in the upper half section of FIG. The position control projection 6g of the second group lens frame 6 is spaced forward from the second group separation control projection 23, and the rear end inclined surface 6h and the transition inclined surface 23b are spaced apart from each other in the optical axis direction. Thereafter, the rear-end inclined surface 6h and the transition inclined surface 23b do not contact each other until the lens barrel storing operation is performed again, and the second group lens frame 6 is continuously held at the insertion holding position. Further, at the wide end in FIG. 21, the interval between the shutter block SB and the third lens group LG3 is larger than in the state of FIG. In the zoom range from the wide end to the tele end, the second group lens moving frame 8 is not moved backward from the position of FIG. 21, and the third group lens frame 7 is moved forward from the illustrated position by driving the AF motor 31. It is possible to perform a focusing operation.

When the lens barrel is stored from the wide-end shooting state, the reverse operation is performed. Although details of the overlapping description are omitted, first, as shown in FIG. 21, the third group lens frame 7 is positioned by the AF motor 31 at the rear movement end in the software control. Subsequently, the second group lens moving frame 8 is moved rearward in the optical axis direction by driving the zoom motor 30 in the retracting direction, and eventually retracts together with the second group lens moving frame 8 as shown in FIG. The rear end inclined surface 6h abuts on the transition inclined surface 23b of the second group separation control projection 23a. Here, when the backward movement of the second group lens frame 6 is continued, the second group lens frame 6 rotates from the insertion holding position to the separation holding position as shown in FIG. 19 due to the relationship between the rear end inclined surface 6h and the transition inclined surface 23b. Moved. In addition, the rear part of the shutter block SB that is moved rearward in the optical axis direction together with the second group lens moving frame 8 is in contact with the front surface of the third group lens frame 7 during the rotation of the second group lens frame 6 to the separation holding position. In contact therewith, the third group lens frame 7 is pressed rearward against the urging force of the third group urging spring 39, and is brought closer to the CCD support plate 23 than the rear movement end controlled by software.

If the second group lens frame 6 completes the rotation to the separation holding position and the second group lens moving frame 8 continues to move backward, the third group lens pushed backward by the shutter block SB as shown in FIG. The rear surface of the frame 7 comes into contact with the front surface of the CCD support frame 23, and the backward movement of the third group lens frame 7 and the shutter block SB is restricted.

Even after the shutter block SB is retracted, the second group lens moving frame 8 and the second group lens frame 6 are continuously retracted. Then, the second group lens is moved relative to the stopped shutter block SB against the urging force of the shutter pressing spring 37 in such a manner that the distance between the front flange portion 9a and the inner diameter flange portion 8c of the shutter support ring 9 is reduced. The frame 8 and the second group lens frame 6 are relatively moved rearward. As a result, as shown in FIG. 17, the lens barrel 6a of the second group lens frame 6 enters the second group storage recess 9g. By this relative movement in the optical axis direction, the rotation restricting surface 6j of the rotation restricting projection 6i of the second group lens frame 6 is moved to a position facing the rotation restricting surface 9p of the shutter support ring 9, and the CCD support plate 23 is moved. Apart from the engagement relationship between the second group separation control projection 23a and the position control projection 6g, the second group lens frame 6 is also rotated to the insertion holding position by the contact relationship between the rotation restricting surface 6j and the rotation restricting surface 9p. Will be regulated.

As shown in FIG. 22 in which the state of FIG. 18 is partially enlarged, the stage immediately before the rotation restricting surface 6j and the rotation restricting surface 9p come into contact with each other in the lens barrel storing operation (the second group disengaging control projection 23a causes At the stage where the lens frame 6 is rotated to the separation holding position), the rotation restriction is performed in front of the boundary corner portion (detachment assisting portion) 9s between the front flange portion 9a and the rotation restriction surface 9p in the shutter support ring 9. An inclined surface portion 6k formed on the protrusion 6i is located. When the second group lens frame 6 approaches the shutter support ring 9 from this state, the inclined surface portion 6k comes into contact with the boundary corner portion 9s, and the second group lens frame 6 is further detached by the inclined shape of the inclined surface portion 6k. A component force that rotates in the direction is generated. As a result, the second group lens frame 6 is slightly displaced in the detaching direction, and comes into contact with the rotation restricting surface 9p so that the rotation restricting surface 6j gets over the boundary corner portion 9s. In this way, a contact portion (detachment) that applies a relative movement in the direction of the optical axis between the second group lens frame 6 and the shutter support ring 9 and applies a moving force in the direction of the separation holding position to the second group lens frame 6. By providing the auxiliary portion, it is possible to prevent malfunction (state in which the second group lens frame 6 cannot be retracted) caused by the collision between the second group lens frame 6 and the shutter support ring 9 during the lens barrel storing operation. . Note that a portion corresponding to the inclined surface portion 6k can be formed on the shutter support ring 9 side.

  Further, when the second group lens moving frame 8 and the second group lens frame 6 relatively move rearward with respect to the stopped shutter block SB, the movement restriction between the inner diameter flange portion 8c of the second group lens moving frame 8 and the shutter support ring 9 is controlled. The interval between the plates 9i is reduced, and the shutter pressing spring 37 is compressed. At this time, the shutter pressing spring 37 is prevented from buckling by the outer peripheral surface of the concentric advance / retreat support tube 9j and the inner peripheral surface of the connection wall 9r.

  When the storage operation up to the storage position in FIG. 17 is completed, the first lens group frame 4 is retracted until it comes into contact with the front end annular rib 9c of the shutter support ring 9 as shown in FIG. 1, and the first lens group LG1 and the shutter block SB The interval of is also packed. The zoom lens barrel 1 is in a storage state in which the storage length in the optical axis direction from the first lens group LG1 to the reference plane Q3 on the CCD support plate 23 is extremely shortened.

  According to the zoom lens barrel 1 having the above configuration, in the second group lens moving frame 8, the second lens group LG2 arranged at a predetermined fixed interval along the optical axis O in the photographing state (zoom photographing region). The shutter block SB is stored in such a manner that the positions in the optical axis direction overlap each other (overlap in a plane orthogonal to the optical axis O) in the lens barrel storage state. Therefore, the storage space occupied by the second lens group LG2 and the shutter block SB in the optical axis direction is small, and a conventional lens barrel having a retracting optical element to the position outside the optical axis like the second lens group LG2 is used. In contrast, the storage length of the zoom lens barrel 1 in the optical axis direction is further shortened.

  More specifically, when shifting from the shooting state of FIG. 2 to the storage state of FIG. 1, the shutter block SB relatively displaces the position in the second group lens moving frame 8 in the storage state. The shutter block SB is positioned near the approximate center of the moving frame 8 in the optical axis direction. Then, the rear part of the first group lens frame 4 enters the second group lens moving frame 8 from the front, the first lens group LG1 approaches to the nearest position in front of the shutter block SB, and the rear part of the third group lens frame 7 The third lens group LG3 enters the second group lens moving frame 8 from the rear, approaches the closest position behind the shutter block SB, and the space from the first lens group LG1 to the third lens group LG3 is a space in the optical axis direction. It is stored efficiently. For example, unlike the present embodiment, if it is assumed that the shutter block SB is fixed at the shooting position in FIG. 2 within the second group lens moving frame 8 even in the lens barrel storage state, the shutter block SB blocks the third position. As shown in FIG. 1, the lens group LG3 cannot enter the second group lens moving frame 8 and overlap with the second lens group LG2 in the detachment state as shown in FIG. The length will be longer. On the other hand, in the present embodiment, the shutter block SB is moved into the space near the center in the second group lens moving frame 8 occupied by the second lens group LG2 at the time of shooting, so that the shutter block SB moves in the housed state. Since a space is made in the rear space of the second group lens moving frame 8 occupied in the photographing state, and this rear space is used as a storage area of the third lens group LG3, high space efficiency is obtained.

  Further, the first lens group LG1 to the third lens group LG3 approach the CCD support plate 23, which is a rear fixing member, and the third lens group LG3 is retracted to a position close to the filter 28. The storage length of the entire optical system including the lens group LG1 to the CCD 24 is shortened, and the zoom lens barrel 1 is thinned.

  In the zoom lens barrel 1 of the present embodiment, the shutter block SB abuts against the third group lens frame 7 and pushes backward by the backward movement of the second group lens moving frame 8 when the lens barrel is stored. Is applied to the CCD support plate 23, the backward movement of the shutter block SB is restricted, and a relative movement in the optical axis direction occurs between the second group lens moving frame 8 that continues the backward movement. That is, no special drive source is required to move the shutter block SB relative to the second group lens moving frame 8 in the optical axis direction when the lens barrel is stored. Relative movement is performed. Further, since the third group lens frame 7 is moved by being pressed by the shutter block SB without being restricted by the AF nut 31b in the rear in the optical axis direction, it is special for retracting the third group lens frame 7 to the storage position. A simple driving source is not required. Therefore, it is possible to avoid complication in terms of mechanism while increasing the space efficiency during storage.

In a conventional three-group type zoom lens, a shutter and a diaphragm are generally arranged in front of the second lens group. On the other hand, in the zoom lens barrel 1 of the present embodiment, the shutter block SB is positioned behind the second lens group LG2 at the time of shooting. This enables an optical design that allows the first lens group LG1 and the second lens group LG2 to approach each other without considering the interference of the shutter block SB at the telephoto end, which is advantageous for downsizing and high zooming of the lens barrel. It has become. Then, the shutter block SB of the second lens group LG2 rear, at the time the barrel retracting by moving relatively in the front in the second lens group moving frame 8, that have been achieved to improve the storage space efficiency as described above.

In the zoom lens barrel 1 of the present embodiment, the second lens group frame 6 that holds the second lens group LG2, the shutter S, and the aperture A are particularly achieved while achieving a reduction in thickness when the lens barrel is accommodated as described above. In the relationship of the shutter block SB that holds the second lens group LG2 while the second lens group LG2 is positioned in the second group storage recess 9g, the disengagement position maintaining means that restricts the return operation of the second lens group LG2 to the insertion holding position The movement restricting projection 6i and the rotation restricting surface 9p) are provided between the second lens group LG2 and the shutter support ring 9. Thereby, interference between the second lens group LG2 and the shutter block SB within the second group lens moving frame 8 can be prevented, and the reliability and stability of the operation in the optical element housing structure can be obtained.

In the above embodiment, when the rear portion of the shutter block SB comes into contact with the front surface of the third group lens frame 7 as the second group lens moving frame 8 is retracted during the lens barrel storing operation, first, the third group lens frame 7. Is moved backward together with the second group lens moving frame 8 and the shutter block SB, and when the third group lens frame 7 is brought into contact with the CCD support plate 23 and the backward movement is restricted, the second group lens is moved with respect to the shutter block SB restricted backward. The moving frame 8 and the second group lens frame 6 are further moved relatively rearward. Unlike this, the spring force of the third group biasing spring 39 that biases the third group lens frame 7 forward is set strongly, and the rear part of the shutter block SB moves to the third group lens as the second group lens moving frame 8 moves backward. At the stage of contact with the front surface of the frame 7, first, the second group lens moving frame 8 and the second group lens frame 6 can be moved relative to the shutter block SB. That is, when the shutter block SB moves backward and comes into contact with the third group lens frame 7, a backward movement force acts on the third group lens frame 7 via the shutter block SB, but the third group biasing spring 39 moves forward. Since the urging force is large, the third group lens frame 7 stays at that position without moving backward. Accordingly, the backward movement of the shutter block SB is also restricted. Therefore, when the second group lens moving frame 8 and the second group lens frame 6 continue to move backward, the relative position of the shutter block SB in the optical axis direction changes. By this relative movement, the lens barrel 6 a of the second group lens frame 6 enters the second group storage recess 9 g of the shutter support ring 9. When the relative movement in the optical axis direction reaches a predetermined amount, the inner diameter flange portion 8c of the second group lens moving frame 8 comes into contact with the front portion of the shutter support ring 9 and resists the biasing force of the third group biasing spring 39. Thus, together with the second group lens moving frame 8 and the second group lens frame 6, the third group lens frame 7 is retracted. In this aspect, since the relative movement of the shutter block SB and the second group lens frame 6 in the optical axis direction is performed at an earlier timing than in the above-described embodiment, at least 2 before the relative movement is started. The length of the second group separation control projection 23a, the shape of the transition inclined surface 23b, and the like are appropriately set so that the movement of the group lens frame 6 to the separation holding position is completed.

  As mentioned above, although demonstrated based on illustration embodiment, this invention is not limited to this embodiment. For example, in the embodiment, the retracting optical element that is moved in the optical axis orthogonal plane within the second group lens moving frame 8 is the second lens group LG2, and the forward and backward optical elements that are also moved in the optical axis direction are the shutter S and the aperture A. However, a retracting optical element and an advancing / retreating optical element in a different combination may be used.

  In the embodiment, the second group lens frame 6 that holds the second lens group LG2 is a rocking (turning) member centered on the second group frame rocking shaft 35, but the retracting optical element is orthogonal to the optical axis. The means for moving in the plane is not limited to such a swinging mechanism, but may be a linear moving mechanism.

It is sectional drawing which shows the accommodation state of the retractable zoom lens barrel to which this invention is applied. It is sectional drawing of the imaging state of the zoom lens barrel. It is a disassembled perspective view which shows a part of main component members of a zoom lens barrel. It is a disassembled perspective view which shows a part of main component members of a zoom lens barrel. It is a disassembled perspective view which shows a part of main component members of a zoom lens barrel. It is a disassembled perspective view which shows a part of main component members of a zoom lens barrel. It is a front perspective view of a shutter support ring. It is a front perspective view of a 2nd group lens frame. It is a back perspective view of a 2nd group lens frame. It is a perspective view which shows the relationship between the 2nd group lens movement frame and CCD support plate in a lens-barrel accommodation state. FIG. 11 is a perspective view showing the second group lens moving frame removed from FIG. 10. It is the perspective view which showed the element inside the 2 group lens movement frame in a lens-barrel accommodation state except this 2 group lens movement frame. It is a perspective view which shows the state which the lens cylinder of the 2nd group lens frame hold | maintained in the separation | holding holding | maintenance position between the lens-barrel accommodation state and imaging | photography states has detached | separated ahead from the 2nd group storage recessed part of a shutter block. It is a perspective view which shows the relationship between the 2 group lens frame hold | maintained in the insertion holding position, and a shutter block. It is a front view of the element inside the 2nd group lens movement frame in a lens barrel storage state. It is a front view of the element inside the 2nd group lens movement frame in an imaging state. It is sectional drawing which showed the optical element from a 2nd lens group to CCD, and the drive element regarding a 2nd lens group and a shutter block in the lens barrel accommodation state, aligning the positional relationship of an optical axis direction. FIG. 18 is a cross-sectional view illustrating a state in which the lens barrel of the second group lens frame is detached forward from the second group storage recess of the shutter block in accordance with the forward movement of the second group lens moving frame from the lens barrel storage state of FIG. 17. FIG. 19 is a cross-sectional view illustrating a state in which the second group lens frame has reached a rotation start position from the separation holding position to the insertion holding position as the second group lens moving frame moves forward from the state of FIG. 18. FIG. 20 is a cross-sectional view illustrating a state in which the second group lens frame has completed the rotation to the insertion holding position as the second group lens movement frame moves forward from the state of FIG. 19. FIG. 21 is a cross-sectional view of a wide-end shooting state in which the second group lens moving frame is further moved forward from the state of FIG. 20. FIG. 19 is an enlarged view showing a positional relationship between a position control protrusion and a rotation restriction protrusion of the second group lens frame, a second group separation protrusion of the CCD support plate, and a rotation restriction surface of the shutter support ring in the state of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Zoom lens barrel 4 1st group lens frame 5 1st group support ring 6 2nd group lens frame 6a Lens cylinder (1st holding member)
6b Oscillating arm 6c Oscillating center cylinder 6d Intermediate flange 6e Stopper arm 6f Large diameter cylinder 6g Position control projection 6h Rear end inclined surface 6i Rotation regulating projection (detachment position maintaining means)
6j Rotation restriction surface (detachment position maintaining means)
6k inclined surface part (detachment assist part)
7 Group 3 lens frame (advance control means)
8 2 group lens moving frame (support ring)
8a Linear groove 8b Cam follower for second group 8c Inner diameter flange portion 8d Notch 8e 8f Spring storage portion 8g Stopper 8h Shaft support hole 8i Rail-shaped portion 8j Spring hook 9 Shutter support ring (second holding member)
9a Front flange portion 9b Front opening portion 9c Front end annular rib 9d Partial cylindrical surface 9e First notch portion 9f Second notch portion 9g Group 2 storage recess (storage portion)
9h Third notch 9i Movement restricting plate 9k Boss engaging hole 9m Protrusion engaging hole 9n Escape recess 9p Rotation restricting surface (detachment position maintaining means)
9r Connection wall 9s Boundary corner (detachment assist part)
10 Shutter member (second holding member)
10a Shutter aperture (shooting aperture)
10b Flexible substrate 10c Side 10c
10c1 Upper notch 10c2 Intermediate notch 10c3 Lower notch 10d Lower recess 10e Side notch 11 Lens barrel housing 12 Helicoid ring 13 First feed cylinder 14 Straight guide ring 16 Second feed cylinder 17 Cam ring 17b Two-group control cam groove 17c 1st group control cam groove 18 2nd rectilinear guide ring 19 3rd feed cylinder 21 Zoom gear 22 3rd group guide shaft 23 CCD support plate (advance / retreat control means, rear fixed member)
23a 2nd group separation protrusion (insertion / removal control means, separation guide part)
23b Transition slope (cam surface)
23c Side 24 CCD (Image sensor)
28 Filter 30 Zoom motor 31 AF motor 32 Intergroup bias spring 33 Second group frame return spring (insertion / removal control means, biasing member)
34 Second-group frame biasing spring 35 Second-group frame swinging shaft 36 Shutter guide shaft 37 Shutter pressing spring (advance / retreat control means)
38 Holding plate 38a 38b Shaft support hole 38c Protrusion insertion hole 38d Movement restricting recess 39 Third group biasing spring A Aperture (advance / retreat optical element, light quantity adjusting member)
LG1 First lens group LG2 Second lens group (retraction optical element)
LG3 Third lens group O Optical axis S Shutter (advance / retreat optical element, light amount adjusting member)
SB shutter block

Claims (6)

A support ring that is moved backward in the optical axis direction when the imaging state is changed to the storage state ;
An insertion holding position that holds the retracting optical element and positions the retracting optical element at a photographing position on the photographing optical axis; and a separation holding position that positions the retracting optical element at a separating position eccentric to the photographing optical axis. A first holding member movably supported in the support ring ;
The forward and backward optical element support, a second holding member that is supported so as to be moved in the optical axis direction within the supporting ring;
The first holding member is held in the inserted holding position in the photographing state, when it comes to storage state to disable taken from the photographing state, the withdrawal holding the first holding member by the rearward movement of the support ring Insertion / removal control means for moving to a position;
The shooting state, the optical axis direction behind the retracting optical elements in the imaging position is located the reciprocating optical element, in the retracted state, at least a portion of the retracting optical element and the reciprocating optical element in the disengagement position as the optical axis direction position overlaps, advance and retreat control means for varying the optical axis direction position of the second holding member in the support ring by a rearward movement of the support ring;
Provided in the first holding member and the second holding member, at the transition from the storage state to the photographing state, independent of the said insertion and extraction control means, to said inserted holding position from the disengaged holding position disengaged position maintaining means for the regulating movement of the first holding member; and
The second holding member is provided between the first holding member and the second holding member, and comes into contact with the second moving member in the support ring by the advance / retreat control means when abutting in the middle of the transition from the photographing state to the stored state. A detachment assisting unit that applies a moving force in the direction of the detachment holding position to the first holding member separately from the movement force in the optical axis direction of the holding member;
A lens barrel characterized by comprising: In the lens barrel according to claim 1, wherein the second holding member is provided with a storage unit in the optical axis direction rear extension on the withdrawal position of the retreat optical element, the retracted optical element to the storage unit in the above storage conditions Entered,
Said disengaged position maintaining means, when said first holding member and the second holding member is in the relative position of the optical axis direction to store the retreat optical element to said storing portion, said insert from said disengaged holding position a lens barrel for regulating the movement of the first holding member to the holding position. In the lens barrel according to claim 1 or 2 wherein said first holding member is moved into the insertion holding position and the disengaged holding position by the swinging around the axis parallel to the photographing optical axis,
The disengagement position maintaining means is formed on one of the first and second holding members and opposed to the rotation direction about the swing axis of the first holding member, and the axis of the swing shaft A lens barrel comprising a pair of rotation restricting surfaces that are substantially parallel to each other. In the lens barrel according to any one of claims 1 to 3, the upper Symbol insertion and removal control means includes an urging member for urging the first holding member in the insertion holding position direction, the rear of the fixing member provided, and a said support engages with the holding member of the first against the biasing member leaving the guide portion to cause movement force component to said disengaged holding position direction during backward movement of the ring Lens barrel. In the lens barrel according to any one of claims 1 to 4, the retracted optical element is a lens unit, the reciprocating optical element lens barrel is light amount adjustment member for changing the opening diameter of the photographic aperture. The lens barrel according to any one of claims 1 to 5, a variable focal length of the zoom lens barrel, when the zooming operation of the photographing state, the retracted optical element and the reciprocating optical elements in the optical axis direction A lens barrel that is integrally moved in the optical axis direction at a constant interval.

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