JP2004258636A - Straight advance guiding mechanism of lens barrel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve straight advance guiding accuracy to a movable element and to decrease resistance at the driving time in the straight advance guiding mechanism of a lens barrel. <P>SOLUTION: The straight advance guiding mechanism of the lens barrel is equipped with an outer movable ring supporting a 1st optical element; an inner movable ring positioned at an inner radial position of the outer movable ring and supporting a 2nd optical element; a 1st straight advance guiding ring guiding the outer movable ring to advance straight in the optical axis direction; a 2nd straight advance guiding ring guiding the inner movable ring to advance straight in the optical axis direction; and a non-rotating common straight advance ring having a straight advance guiding part with which the 1st and the 2nd straight advance guiding rings are respectively slidably engaged and which is parallel with an optical axis on the inner peripheral surface. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a linear guide mechanism in a lens barrel.

  When the lens barrel has two or more members that are guided in a straight line in the direction of the optical axis, the straight guide structure generally inherits the members for straight guide in a single path in order. For example, a double-sided cam ring is known in which movable elements on the outer diameter side and the inner diameter side are individually moved by cam grooves provided on both the outer peripheral surface and the inner peripheral surface. In this type of cam feeding device, the movable element on the outer diameter side and the movable element on the inner diameter side are respectively guided straight in a direction parallel to the rotation axis of the double-sided cam ring. While the members are located on the radial side and the inner diameter side, the member that performs the straight guide (hereinafter, the straight guide member) is located on the outer diameter side of the cam ring. In such a case, in the past, a straight-line guide structure having a single path in which a reference straight guide member linearly guides the movable element on the outer diameter side and the movable element on the outer diameter guides the movable element on the inner diameter side in a straight line. Was taken.

  In the single-path straight guide structure as described above, two movable elements that are moved linearly (for example, in the example using the double-sided cam ring, a movable element on the outer diameter side of the cam ring and a movable element on the inner diameter side). When the relative movement speed between the two is high, there is a possibility that the resistance for the straight traveling guidance will increase. In particular, when the driving force for moving the movable element forward and backward is given by a rotating member such as a cam ring, the resistance at the straight guide portion tends to increase. Further, in the straight traveling guide structure with a single path, it is difficult to indirectly move other members (the other straight traveling.) Therefore, the present invention provides a linear traveling guide mechanism for a lens barrel. It is an object of the present invention to improve the accuracy of straight-line guidance and reduce the resistance during driving.

  An outer movable ring that supports a first optical element; an inner movable ring that is located radially inside the outer movable ring and supports a second optical element; and an outer movable ring that supports the first optical element. A first linear guide ring that guides the ring in the optical axis direction; a second linear guide ring that guides the inner movable ring in the optical axis direction; and the first and second linear guide rings are slidable. A non-rotatable common linear guide ring having a linear guide portion parallel to the optical axis on the inner peripheral surface thereof.

  The first straight guide ring may be located radially outward of the outer movable ring, and the shared straight guide ring may be located radially outside of the first straight guide ring.

  It is preferable that the shared straight guide ring includes at least a pair of straight guide portions with which the first straight guide ring and the second straight guide ring individually engage. Specifically, each of the first straight guide ring and the second straight guide ring includes at least one straight guide protrusion (first and second straight guide protrusion) protruding in the outer diameter direction, and is a shared straight guide ring. It is preferable to form first and second rectilinear guide grooves parallel to the optical axis with which the rectilinear guide protrusions slidably engage, respectively. It is preferable that a plurality of the first straight guide grooves and the second straight guide grooves are provided at different positions in the circumferential direction.

  It is preferable that one of the first straight guide groove and the second straight guide groove is provided as a pair at both circumferential positions sandwiching the other. In this case, one of the first straight guide protrusion and the second straight guide protrusion is formed so as to simultaneously engage with the pair of straight guide grooves across the other straight guide groove. Is preferred.

  The first rectilinear guide ring has at least one rectilinear guide groove parallel to the optical axis on the inner peripheral surface, and the outer movable ring includes at least one rectilinear slide slidably engaged with the rectilinear guide groove. It is preferable to have a guide projection on the outer peripheral surface.

  Further, the second linear guide ring has at least one linear guide key extending in a direction parallel to the optical axis, and the inner movable ring has at least one linear guide key slidably engaged with the linear guide key. It is preferable to have two rectilinear guide grooves.

  The present invention is preferably applied to a lens barrel having a double-sided cam ring having at least one cam groove on both the outer peripheral surface and the inner peripheral surface. In this case, the outer movable ring is located radially outward of the double-sided cam ring and has at least one cam follower that engages with the outer surface cam groove of the double-sided cam ring, and the inner movable ring is located radially inward of the cam ring. It is preferable to have at least one cam follower positioned and engaged with the inner cam groove of the double-sided cam ring. In this case, it is preferable that the second rectilinear guide ring has a ring portion supported at the rear end in the optical axis direction of the double-sided cam ring so as to be relatively rotatable and relatively immovable in the optical axis direction.

  The shared straight guide ring may be supported by itself so as to be able to move straight in the optical axis direction with respect to the fixed ring.

  The present invention is suitable for, for example, a zoom lens barrel in which a first optical element supported by an outer movable ring and a second optical element supported by an inner movable ring are each a movable lens group.

  The present invention also includes a double-sided cam ring having cam grooves on both the outer peripheral surface and the inner peripheral surface; and a cam follower positioned radially outside the double-sided cam ring and engaging with the cam groove on the outer peripheral surface of the double-sided cam ring. An outer movable ring supporting the first optical element; supporting a second optical element having a cam follower located radially inside the double-sided cam ring and engaging with a cam groove on an inner peripheral surface of the double-sided cam ring. An inner movable ring; a non-rotatable shared linear guide ring which is located radially outside of the double-sided cam ring and has a linear guide portion parallel to the optical axis on its inner peripheral surface; and a linear guide portion of the shared linear guide ring. Are directly guided in the optical axis direction, and are provided with first and second linear guide transmission members that respectively guide the outer movable ring and the inner movable ring individually in the optical axis direction.

As described above, according to the present invention, in a lens barrel having a plurality of movable elements, it is possible to achieve an improvement in linear guide accuracy with respect to the movable elements and a reduction in resistance during driving.

  Hereinafter, the present invention will be described based on the illustrated embodiments. In some drawings, the thickness of the external line is different or the line type is different for each member in order to facilitate identification of the member. In addition, in the cross-sectional views, there are actually different positions in the circumferential direction, but there are some portions that are shown on the same cross-section in the drawing.

[Overall description of zoom lens barrel]
First, the overall structure of the zoom lens barrel 71 of the present embodiment will be described with reference to FIGS. As shown in FIGS. 6 and 7, the zoom lens barrel 71 is mounted on the digital camera 70, and the photographing optical system includes, in order from the object side, a first lens group LG1, a shutter S and an aperture A, and a second lens. The optical system includes a group LG2, a third lens group LG3, a low-pass filter (filters) LG4, and a CCD (solid-state imaging device) 60. The optical axis of the photographing optical system is Z1. The photographing optical axis Z1 is parallel to the rotation center axis (hereinafter, referred to as the barrel center axis Z0) of each of the annular members constituting the appearance of the zoom lens barrel 71, and is parallel to the barrel center axis Z0. Eccentric downward. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 back and forth along a predetermined trajectory in the direction of the photographing optical axis Z1, and focusing is performed by moving the third lens group LG3 in the same direction. In the following description, the term “optical axis direction” means a direction parallel to the photographing optical axis Z1 unless otherwise specified.

  As shown in FIGS. 6 and 7, the fixed ring 22 is fixed in the camera body 72, and the CCD holder 21 is fixed to the rear of the fixed ring 22. The CCD 60 is supported on the CCD holder 21 via a CCD base plate 62, and a low-pass filter LG 4 is supported in front of the CCD 60 via a filter holder 73 and a packing 61. The filter holder 73 is integrally formed as a part of the CCD holder 21. An LCD 20 for displaying images and photographing information is provided at the rear of the CCD holder 21.

  An AF lens frame (third group lens frame) 51 that holds the third lens group LG3 is supported in the fixed ring 22 so as to be able to move straight in the optical axis direction. That is, the front end and the rear end of a pair of AF guide shafts 52 and 53 parallel to the photographing optical axis Z1 are fixed to the fixed ring 22 and the CCD holder 21, respectively. Guide holes 51a and 51b formed in the AF lens frame 51 are slidably fitted respectively. In the present embodiment, the clearance between the AF guide shaft 53 and the guide hole 51b is larger than the clearance between the AF guide shaft 52 and the guide hole 51a. That is, the AF guide shaft 52 is a main (exactly accurate) guide shaft, and the AF guide shaft 53 is a sub (non-rotating) guide shaft. The AF nut 54 is screwed into a feed screw formed on the drive shaft of the AF motor 160. As shown in FIG. 1, the AF nut 54 has a rotation restricting protrusion 54a, the AF lens frame 51 has a guide groove 51m in the optical axis direction, and the rotation restricting protrusion 54a can slide with respect to the guide groove 51m. Is stuck in. The AF lens frame 51 further has a stopper projection 51n located behind the AF nut 54. The AF lens frame 51 is urged forward by an AF frame urging spring 55, and the forward movement end of the AF lens frame 51 is determined by the stopper projection 51 n abutting against the AF nut 54. When the AF nut 54 moves rearward in the optical axis direction, the AF lens frame 51 is pressed by the AF nut 54 and moves rearward. With the above structure, when the drive shaft of the AF motor 160 is rotated in the normal or reverse direction, the AF lens frame 51 is moved forward and backward in the optical axis direction. It is also possible to directly press the AF lens frame 51 (without using the AF nut 54) and move the AF lens frame 51 backward against the AF frame urging spring 55.

  As shown in FIG. 5, a zoom motor 150 and a reduction gear box 74 are supported on the upper part of the fixed ring 22. The reduction gear box 74 has a reduction gear train therein and transmits the driving force of the zoom motor 150 to the zoom gear 28. The zoom gear 28 is pivotally attached to the fixed ring 22 by a zoom gear shaft 29 parallel to the photographing optical axis Z1. The zoom motor 150 and the AF motor 160 are controlled by a camera control circuit 140 (FIG. 19) via a lens drive control FPC (flexible printed circuit) board 75 disposed on the outer peripheral surface of the fixed ring 22.

  On the inner peripheral surface of the fixed ring 22, a female helicoid 22a, three rectilinear guide grooves 22b parallel to the photographing optical axis Z1, three oblique grooves 22c parallel to the female helicoid 22a, and each oblique groove 22c are formed. A circumferential sliding groove 22d communicating with the front end is formed in the circumferential direction. The rotary sliding groove 22d is formed near the front end of the fixed ring 22, and the female helicoid 22a is not formed in the front annular region 22z immediately after the rotary sliding groove 22d (see FIG. 8).

  The helicoid ring 18 has a male helicoid 18a screwed into the female helicoid 22a and a rotary sliding projection 18b located in the oblique groove 22c and the rotary sliding groove 22d on the outer peripheral surface (FIG. 4, FIG. (FIG. 9). A spur gear portion 18c having gear teeth parallel to the photographing optical axis Z1 is formed on the male helicoid 18a, and the spur gear portion 18c is screwed with the zoom gear 28. Accordingly, when a rotational force is applied from the zoom gear 28 to the spur gear portion 18c, the helicoid ring 18 advances and retreats in the optical axis direction while rotating when the female helicoid 22a and the male helicoid 18a are in a screwing relationship with each other. When the male helicoid 18a moves, the male helicoid 18a is disengaged from the female helicoid 22a, and only the circumferential rotation about the lens barrel center axis Z0 is performed by the engagement relationship between the rotary sliding groove 22d and the rotary sliding protrusion 18b.

  The skew groove 22c is a relief groove formed to avoid interference between the rotary sliding protrusion 18b and the fixed ring 22 when the female helicoid 22a and the male helicoid 18a are screwed, and the skew groove 22c is a female helicoid 22a. Is deeper than the bottom. In the female helicoid 22a, the circumferential interval between a pair of helicoid mountains sandwiching each of the oblique grooves 22c is wider than the circumferential interval between the other helicoid mountains, and the male helicoid 18a is mounted on the helicoid mountain having the wide circumferential interval. For engagement, the three helicoid peaks 18a-W located behind the rotary sliding protrusion 18b are circumferentially wider than the other helicoid peaks.

  The fixed ring 22 is further formed with a stopper insertion / removal hole 22e penetrating the outer peripheral surface and the rotary sliding groove 22d, and restricts the rotation of the helicoid ring 18 beyond the photographing area with respect to the stopper insertion / removal hole 22e. To be disassembled is removable.

  A rotation transmitting projection 15a (FIG. 11) projecting rearward from the rear end of the third outer cylinder 15 fits into a rotation transmitting recess 18d (FIGS. 4 and 10) formed on the inner peripheral surface of the front end of the helicoid ring 18. Have been. The rotation transmitting recesses 18d and the rotation transmitting projections 15a are provided at three positions at different positions in the circumferential direction, and the rotation transmitting projections 15a and the rotation transmitting recesses 18d corresponding to the circumferential positions correspond to the center axis of the lens barrel. Relative sliding in the direction along Z0 is connected so as to be possible, and relative rotation is not possible in the circumferential direction around the lens barrel center axis Z0. That is, the third outer cylinder 15 and the helicoid ring 18 rotate integrally. The helicoid ring 18 has a fitting recess 18e formed by cutting out a part of the inner diameter side of the rotary sliding projection 18b, and the fitting projection 15b fitted into the fitting recess 18e is rotated. When the sliding protrusion 18b engages with the rotating sliding groove 22d, it simultaneously engages with the rotating sliding groove 22d (see the upper half section of the mirror zoom lens barrel in FIG. 6).

  Between the third outer cylinder 15 and the helicoid ring 18, there are provided three separation-direction biasing springs 25 for biasing each other in the separation direction in the optical axis direction. The separation-direction urging spring 25 is formed of a compression coil spring, and its rear end is housed in a spring insertion recess 18 f that opens to the front end of the helicoid ring 18, and its front end contacts the spring-attached recess 15 c of the third outer cylinder 15. In contact. Pressing the fitting projection 15b toward the front wall surface of the rotary sliding groove 22d and pressing the rotary sliding protrusion 18b toward the rear wall surface of the rotary sliding groove 22d by the separating direction urging spring 25. Thus, the backlash of the third outer cylinder 15 and the helicoid ring 18 with respect to the fixed ring 22 in the optical axis direction is eliminated.

  On the inner peripheral surface of the third outer cylinder 15, a claw-shaped relative rotation guide projection 15d protruding in the inner diameter direction, a circumferential groove 15e centered on the lens barrel center axis Z0, and a photographing optical axis Z1 are provided. Three parallel roller fitting grooves 15f are formed (FIGS. 4 and 11). A plurality of relative rotation guide protrusions 15d are provided at different positions in the circumferential direction. The roller fitting groove 15f is formed at a circumferential position corresponding to the rotation transmitting protrusion 15a, and a rear end portion thereof is opened rearward through the rotation transmitting protrusion 15a. A circumferential groove 18g centering on the lens barrel center axis Z0 is formed on the inner circumferential surface of the helicoid ring 18 (FIGS. 4 and 10). A straight guide ring 14 is supported inside the combined body of the third outer cylinder 15 and the helicoid ring 18. Three rectilinear guide protrusions 14a protruding in the radial direction are sequentially provided on the outer peripheral surface of the rectilinear guide ring 14 from the rear in the optical axis direction, and a plurality of claw-shaped relative rotation guides provided at different positions in the circumferential direction. Protrusions 14b and 14c and a circumferential groove 14d centered on the lens barrel center axis Z0 are formed (FIGS. 4 and 12). The linear guide ring 14 is guided linearly in the optical axis direction with respect to the fixed ring 22 by engaging the linear guide protrusion 14a with the linear guide groove 22b. Further, the third outer cylinder 15 engages the circumferential groove 15e with the relative rotation guide protrusion 14c and engages the relative rotation guide protrusion 15d with the circumferential groove 14d, so that the third outer cylinder 15 is It is rotatably connected. The circumferential groove 15e and the relative rotation guide protrusion 14c, and the circumferential groove 14d and the relative rotation guide protrusion 15d are each loosely fitted so as to be relatively movable in the optical axis direction. Further, the helicoid ring 18 is also relatively rotatably coupled to the rectilinear guide ring 14 by engaging the circumferential groove 18g with the relative rotation guide protrusion 14b. The circumferential groove 18g and the relative rotation guide protrusion 14b are loosely fitted so as to be able to relatively move relatively in the optical axis direction.

  The linear guide ring 14 is formed with three roller guide through grooves 14e penetrating the inner peripheral surface and the outer peripheral surface. As shown in FIG. 12, each of the roller guide through grooves 14e includes parallel front and rear circumferential grooves 14e-1 and 14e-2 formed in the circumferential direction, and the circumferential grooves 14e-1 and 14e-2. And a lead groove 14e-3 for connection. A cam ring roller 32 provided on the outer peripheral surface of the cam ring 11 is fitted into each roller guide through groove 14e. The cam ring rollers 32 are fixed to the cam ring 11 via roller fixing screws 32a, and three cam ring rollers are provided at different positions in the circumferential direction. The cam ring roller 32 further penetrates the roller guide through groove 14e and is fitted in the roller fitting groove 15f on the inner peripheral surface of the third outer cylinder 15. Near the front end of each roller fitting groove 15f, three roller pressing pieces 17a provided on the roller urging spring 17 are fitted (FIG. 11). The roller pressing piece 17a comes into contact with the cam ring roller 32 and presses backward when the cam ring roller 32 engages with the circumferential groove portion 14e-1, and the cam ring roller 32 and the roller guide through groove 14e (in the circumferential direction). Backlash between the groove 14e-1) is removed.

  From the structure described above, the manner in which the fixed ring 22 extends from the cam ring 11 is understood. That is, when the zoom gear 28 is rotationally driven by the zoom motor 150 in the lens barrel extending direction, the helicoid ring 18 is extended forward while rotating due to the relationship between the female helicoid 22a and the male helicoid 18a. The helicoid ring 18 and the third outer cylinder 15 are relatively rotatable and rotatable with respect to the rectilinear guide ring 14 due to the engagement relationship between the circumferential grooves 14d, 15e and 18g and the relative rotation guide projections 15d, 14c and 14b, respectively. The third outer cylinder 15 is also extended forward while rotating in the same direction when the helicoid ring 18 is rotationally extended since the coupling is performed so as to move together in the axial direction (the direction along the lens barrel center axis Z0). Then, the straight guide ring 14 moves straight forward together with the helicoid ring 18 and the third outer cylinder 15. The rotational force of the third outer cylinder 15 is transmitted to the cam ring 11 via the roller fitting groove 15f and the cam ring roller 32. Since the cam ring roller 32 is also fitted into the roller guide through groove 14e, the cam ring 11 is extended forward with respect to the straight guide ring 14 while rotating according to the shape of the lead groove 14e-3. As described above, since the rectilinear guide ring 14 itself is also rectilinearly moving forward together with the third outer cylinder 15 and the helicoid ring 18, as a result, the cam ring 11 is provided with the rotation extension according to the lead groove 14e-3 and the rectilinear guide. The moving amount in the optical axis direction is given by adding the amount of forward movement of the ring 14 to the front.

  The above-described feeding operation is performed while the male helicoid 18a and the female helicoid 22a are screwed together, and at this time, the rotary sliding projection 18b moves in the oblique groove 22c. When the helicoid ring 18 and the third outer cylinder 15 are extended by a predetermined amount, the screw engagement between the male helicoid 18a and the female helicoid 22a is released, and the rotary sliding projection 18b and the fitting projection 15b are eventually rotated from the oblique groove 22c. It enters the moving groove 22d. Then, since the rotation repetition output by the helicoid does not work, the helicoid ring 18 and the third outer cylinder 15 are moved in the optical axis direction by the engagement relationship between the rotation sliding protrusion 18b and the fitting protrusion 15b and the rotation sliding groove 22d. Only rotation is performed at a fixed position. At substantially the same time when the rotary slide protrusion 18b enters the rotary slide groove 22d from the oblique groove 22c, the cam ring roller 32 enters the circumferential groove portion 14e-1 of the roller guide through groove 14e. Then, no forward moving force is applied to the cam ring 11, and the cam ring 11 only rotates at a fixed position according to the rotation of the third outer cylinder 15.

  When the zoom gear 28 is driven to rotate in the lens barrel housing direction, the reverse operation is performed. When the helicoid ring 18 is rotated until the cam ring roller 32 enters the circumferential groove 14e-2 of the roller guide through groove 14e, each of the above-mentioned lens barrel members is retracted to the position shown in FIG.

  Subsequently, the structure before the cam ring 11 will be described. On the inner peripheral surface of the rectilinear guide ring 14, three first rectilinear guide grooves 14f and six second rectilinear guide grooves 14g parallel to the photographing optical axis Z1 are formed at different positions in the circumferential direction. . The first rectilinear guide grooves 14f include a pair of grooves located on both sides of three of the six second rectilinear guide grooves 14g. The three crotch-shaped protrusions 10a (FIGS. 3 and 15) provided on the front panel are slidably engaged. On the other hand, the six rectilinear guide projections 13a (FIGS. 2 and 17) protruding from the outer peripheral surface of the rear end of the second outer cylinder 13 are slidably engaged with the second rectilinear guide grooves 14g. I have. Therefore, both the second outer cylinder 13 and the second group straight guide ring 10 are guided straight through the straight guide ring 14 in the optical axis direction.

  The second group straight guide ring 10 is a member for guiding the second group lens moving frame 8 that supports the second lens group LG2 straight, and the second outer cylinder 13 is a first outer cylinder that supports the first lens group LG1. It is a member for guiding the cylinder 12 straight.

  First, the support structure of the second lens group LG2 will be described. The second group straight guide ring 10 has three straight guide keys 10c protruding forward from a ring portion 10b connecting the three crotch-shaped protrusions 10a (FIGS. 3 and 15). As shown in FIGS. 6 and 7, the outer edge of the ring portion 10b can rotate relative to the circumferential groove 11e formed on the inner peripheral surface of the rear end of the cam ring 11, but cannot move relative to the optical axis. The straight guide key 10c is extended inside the cam ring 11. Each of the rectilinear guide keys 10 c has a pair of guide surfaces parallel to the photographing optical axis Z <b> 1, and the guide surfaces are formed by the rectilinear guide grooves of the second lens group moving frame 8 supported inside the cam ring 11. The second group lens moving frame 8 is guided linearly in the axial direction by engaging with the lens 8a. The rectilinear guide groove 8 a is formed on the outer peripheral surface side of the second group lens moving frame 8.

  The second group straight guide ring 10 is provided with three straight guide keys 10c at different positions in the circumferential direction, and one of the straight guide keys 10c-W is provided with an exposure control FPC (described later). In order to also serve as a support member for the flexible printed circuit (PCB) board 77, the width is circumferentially wider than the remaining two straight guide keys 10c. The wide straight guide key 10c-W is formed with an FPC through hole 10d which is partially cut away in the vicinity of the connection portion with the ring portion 10b and penetrates in the radial direction, and as shown in FIG. The board 77 extends from the rear of the ring portion 10b to the outer peripheral surface side of the linear guide key 10c-W through the FPC through hole 10d, and is bent rearward at the tip of the linear guide key 10c-W. Correspondingly, one of the three rectilinear guide grooves 8a is a wide rectilinear guide groove 8a-W to which the wide rectilinear guide key 10c-W can be engaged. A central portion of the straight guide groove 8a-W is a through portion through which the exposure control FPC board 77 can pass. A bottom portion for supporting the straight guide key 10c-W is provided on both sides of the through portion. Is formed. On the other hand, the remaining two rectilinear guide grooves 8 a are both bottomed grooves formed on the outer peripheral surface side of the second group lens moving frame 8. The second group lens moving frame 8 and the second group straight guide ring 10 can be combined only in a specific rotation phase in which the straight guide keys 10c-W can engage with the straight guide grooves 8a-W.

  A second group guide cam groove 11 a is formed on the inner peripheral surface of the cam ring 11. As shown in FIG. 14, the second group guide cam groove 11a includes a front cam groove 11a-1 and a rear cam groove 11a-2 whose positions are different in the optical axis direction and the circumferential direction. Each of the front cam groove 11a-1 and the rear cam groove 11a-2 is a cam groove formed by tracing the same base locus α, but does not cover the entire area of the base locus α. The front cam groove 11a-1 and the rear cam groove 11a-2 differ from each other in a part of the area occupied on the basic locus α. The basic trajectory is a conceptual cam groove shape including all the lens barrel use areas (use areas) including the zoom area and the storage area, and the lens barrel assembly / disassembly area. That is, the lens barrel use area is an area in which the movement of the second lens group moving frame 8 can be controlled by the cam groove shape, and is used to distinguish it from the assembly and disassembly area. Further, the zoom area is an area for controlling movement between the wide end and the tele end particularly in the lens barrel use area, and is used to distinguish it from the storage area. When a pair of the front cam groove 11a-1 and the rear cam groove 11a-2 are formed as one group, the cam ring 11 is formed with three groups of second group guide cam grooves 11a at equal intervals in the circumferential direction.

  The second group cam follower 8b provided on the outer peripheral surface of the second group lens moving frame 8 is engaged with the second group guide cam groove 11a. Similarly to the second group guide cam groove 11a, the second group cam followers 8b are also circumferentially equally spaced as a group of a pair of front cam followers 8b-1 and rear cam followers 8b-2 whose positions are different in the optical axis direction and the circumferential direction. The front cam followers 8b-1 engage with the front cam grooves 11a-1, and the rear cam followers 8b-2 engage with the rear cam grooves 11a-2 in the optical axis direction. A circumferential interval is defined.

  Since the second group lens moving frame 8 is guided linearly in the optical axis direction via the second group linear guide ring 10, when the cam ring 11 rotates, the second group lens moving frame 8 is driven in accordance with the second group guide cam groove 11a. It moves along a predetermined trajectory in the axial direction.

  Inside the second group lens moving frame 8, a second group lens frame 6 that holds the second lens group LG2 is supported. The second group lens frame 6 is supported by a pair of second group lens frame support plates 36 and 37 via a second group rotation shaft 33, and the second group frame support plates 36 and 37 are supported plate fixing screws 66. To the second group lens moving frame 8. The second-group rotation axis 33 is parallel to the imaging optical axis Z1 and is eccentric with respect to the imaging optical axis Z1, and the second-group lens frame 6 has the second lens group LG2 with the second-group rotation axis 33 as the rotation center. A photographing position (FIG. 6) where the optical axis of the second lens group LG2 coincides with the photographing optical axis Z1, and a retracting position (FIG. 6) for displacing the optical axis of the second lens group LG2 from the photographing optical axis Z1 to the retracted optical axis Z2. 7). The second group lens moving frame 8 is provided with a rotation restricting pin 35 for restricting the second group lens frame 6 from rotating at the photographing position. The second group lens frame 6 is moved by a second group lens frame returning spring 39. It is urged to rotate in the direction of contact with the rotation restricting pin 35. The axial pressing spring 38 performs backlash removal of the second lens group frame 6 in the optical axis direction.

  The second group lens frame 6 moves integrally with the second group lens moving frame 8 in the optical axis direction. A cam projection 21a (FIG. 4) projects forward from the CCD holder 21 at a position where it can be engaged with the second group lens frame 6. As shown in FIG. When it moves and approaches the CCD holder 21, the cam surface formed at the tip of the cam projection 21a engages with the second lens group frame 6 and rotates to the above-mentioned retracted position for storage.

  Subsequently, a support structure of the first lens group LG1 will be described. On the inner peripheral surface of the second outer cylinder 13 guided straight in the optical axis direction via the straight guide ring 14, three rectilinear guide grooves 13b are formed in the optical axis direction at positions different in the circumferential direction. The three engagement projections 12a formed on the outer peripheral surface near the rear end of the first outer cylinder 12 are slidably fitted into the respective linear guide grooves 13b (FIGS. 2, 17, and 18). reference). That is, the first outer cylinder 12 is guided linearly in the optical axis direction via the straight guide ring 14 and the second outer cylinder 13. The second outer cylinder 13 has an inner peripheral flange 13c on the inner peripheral surface in the vicinity of the rear end thereof, and the inner peripheral flange 13c slides in a circumferential groove 11c provided on the outer peripheral surface of the cam ring 11. By engaging as much as possible, the second outer cylinder 13 is coupled to the cam ring 11 so as to be rotatable relative to the cam ring 11 and not to move relative to the optical axis. On the other hand, the first outer cylinder 12 has three first group rollers (cam followers) 31 protruding in the inner diameter direction, and each first group roller 31 is formed on the outer peripheral surface of the cam ring 11 as one group. It is slidably fitted in the guide cam groove 11b.

  The first lens barrel 1 is supported in the first outer cylinder 12 via a first lens adjusting ring 2. The first lens group LG1 is fixed to the first group lens frame 1, and a male adjustment screw 1a formed on the outer peripheral surface thereof is screwed with a female adjustment screw 2a formed on the inner peripheral surface of the first group adjustment ring 2. . By adjusting the screw position of the adjusting screw, the position of the first lens group frame 1 with respect to the first lens group adjusting ring 2 can be adjusted in the optical axis direction.

  The first group adjusting ring 2 has a pair of (only one is shown in FIG. 2) guide protrusions 2 b protruding in the outer diameter direction, and the pair of guide protrusions 2 b are formed on the inner peripheral surface side of the first outer cylinder 12. Are slidably engaged with the pair of first group adjusting ring guide grooves 12b formed in the first group. The first group adjustment ring guide groove 12b is formed in parallel with the photographing optical axis Z1, and the first group adjustment ring 2 and the first group lens frame 1 are formed by the engagement relationship between the first group adjustment ring guide groove 12b and the guide projection 2b. The combined body can be moved back and forth in the optical axis direction with respect to the first outer cylinder 12. The first group retaining ring 3 is further fixed to the first outer cylinder 12 with a retaining ring fixing screw 64 so as to close the front of the guide protrusion 2b. A first-group urging spring 24 composed of a compression coil spring is provided between the spring receiving portion 3a of the first-group retaining ring 3 and the guide protrusion 2b. It is biased rearward in the axial direction. The first group adjusting ring 2 is formed by engaging an engaging claw 2c protruding from an outer peripheral surface near a front end portion thereof with a front surface (a surface visible in FIG. 2) of the first group retaining ring 3. The maximum movement position in the optical axis direction rearward relative to the one outer cylinder 12 is regulated (see the upper half section in FIG. 6). On the other hand, by compressing the first-group urging spring 24, the first-group adjusting ring 2 can move a little forward in the optical axis direction.

  A shutter unit 76 having a shutter S and an aperture A is supported between the first lens group LG1 and the second lens group LG2. The shutter unit 76 is supported inside the second-group lens moving frame 8, and the shutter S and the aperture A have a fixed air gap between the second lens group LG2. Two actuators 131 and 132 (FIG. 19) for driving the shutter S and the aperture A are respectively arranged at front and rear positions with the shutter unit 76 interposed therebetween. An exposure control FPC board 77 for connecting to the control circuit 140 extends. The exposure control FPC board 77 does not actually exist at the position of the lower half section (wide end) in FIG. 6, but is shown for easy understanding of the positional relationship with other members.

  In addition to the shutter S, a lens barrier mechanism is provided at the front end of the first outer cylinder 12 for closing the photographing aperture when not photographing to protect the photographing optical system (first lens group LG1). The lens barrier mechanism includes a pair of barrier blades 104 and 105 rotatable about a rotation axis provided at a position eccentric to the lens barrel center axis Z0, and biases the barrier blades 104 and 105 in a closing direction. A pair of barrier urging springs 106, a barrier drive ring 103 that is rotatable about a lens barrel center axis Z0 and engages and opens the barrier blades 104, 105 by rotation in a predetermined direction, and the barrier drive ring. A barrier drive ring biasing spring 107 for biasing the rotary shaft 103 in the barrier opening direction is provided, and a barrier pressing plate 102 located between the barrier blades 104 and 105 and the barrier drive ring 103. The urging force of the barrier driving ring urging spring 107 is set stronger than the urging force of the barrier urging spring 106, and when the zoom lens barrel 71 is extended to the zoom region (FIG. 6), the barrier driving ring urging spring 107 is turned on. The biasing spring 107 holds the barrier drive ring 103 at the barrier opening angular position, and the barrier blades 104 and 105 are opened against the barrier biasing spring 106. Then, while the zoom lens barrel 71 is moving from the zoom region to the storage position (FIG. 7), the barrier drive ring pressing surface 11d (FIGS. 3 and 13) of the cam ring 11 causes the barrier drive ring 103 to be opposed to the barrier opening direction. The barrier drive ring 103 is disengaged from the barrier blades 104 and 105 by being forcedly rotated in the direction, and the barrier blades 104 and 105 are closed by the urging force of the barrier urging spring 106. The front of the lens barrier mechanism is covered by a barrier cover 101 (decorative plate).

  The entire extension and storage operation of the zoom lens barrel 71 having the above structure will be described with reference to FIGS. 6, 7, and 19. FIG. FIG. 19 conceptually shows the relationship between the main members of the zoom lens barrel 71, where "S" in parentheses after the reference numeral of each member is a fixed member, and "L" is an optical axis direction. A member that performs only linear movement, “R” means a member that performs only rotation, and “RL” means a member that moves in the optical axis direction while rotating. A member in which two symbols are written in parentheses means that the operation mode is switched at the time of feeding and storage.

  The steps up to the stage in which the cam ring 11 is extended from the storage position to the home position rotation state have already been described, and thus will be briefly described. 7, the zoom lens barrel 71 is completely stored in the camera body 72, and the front surface of the camera 70 has a flat shape in which the zoom lens barrel 71 does not protrude from the camera body 72. I have. When the zoom gear 28 is rotationally driven in the extension direction by the zoom motor 150 from the lens barrel stored state, the combined body of the helicoid ring 18 and the third outer cylinder 15 is rotated and extended in accordance with the helicoid (the male helicoid 18a and the female helicoid 22a). The straight guide ring 14 moves straight forward together with the third outer cylinder 15 and the helicoid ring 18. At this time, the cam ring 11 to which the rotational force is applied by the third outer cylinder 15 has a lead structure (a cam ring roller) provided between the linear guide ring 14 and the linear movement forward. 32, the combined movement with the extended portion by the lead groove portion 14e-3) is performed. When the helicoid ring 18 and the cam ring 11 are extended to a predetermined position in front, the functions of the respective rotating and extending structures (helicoid, lead) are released, and only the circumferential rotation about the lens barrel center axis Z0 is performed. become.

  When the cam ring 11 rotates, the second-group lens moving frame 8 guided straight through the second-group straight guide ring 10 is rotated in the optical axis direction by the relationship between the second-group cam follower 8b and the second-group guide cam groove 11a. Is moved along a predetermined locus. In the lens barrel storage state of FIG. 7, the second group lens frame 6 in the second group lens moving frame 8 is a storage retracting position eccentric upward from the photographing optical axis Z1 by the action of the cam projection 21a protruding from the CCD holder 21. And the second lens group LG2 is located at the retracted optical axis Z2. The second group lens frame 6 separates from the cam projection 21a while the second group lens moving frame 8 is being extended to the zoom region, and moves the optical axis of the second lens group LG2 by the urging force of the second group lens frame return spring 39. It is rotated to a photographing position (FIG. 6) that is coincident with the photographing optical axis Z1. Thereafter, the second group lens frame 6 is held at the photographing position until the zoom lens barrel 71 is moved to the storage position again.

  When the cam ring 11 rotates, outside the cam ring 11, the first outer cylinder 12, which is guided straight through the second outer cylinder 13, has a relationship between the first group roller 31 and the first group guide cam groove 11 b. Is moved along a predetermined locus in the optical axis direction.

  That is, the extension positions of the first lens group LG1 and the second lens group LG2 with respect to the image pickup surface (CCD light receiving surface) are determined by the amount of forward movement of the cam ring 11 with respect to the fixed ring 22 and the first The latter is determined as the sum of the cam extension of the outer cylinder 12 and the latter is the sum of the forward movement of the cam ring 11 with respect to the fixed ring 22 and the cam extension of the second lens unit moving frame 8 with respect to the cam ring 11. Decided. Zooming is performed by moving the first lens group LG1 and the second lens group LG2 on the photographing optical axis Z1 while changing the air gap between them. When the lens barrel is extended from the storage position of FIG. 7, the wide end is first extended as shown in the lower half section of FIG. 6, and when the zoom motor 150 is further driven in the lens barrel extending direction, the upper half section of FIG. As shown in FIG. As can be seen from FIG. 6, the zoom lens barrel 71 of the present embodiment has a large distance between the first lens group LG1 and the second lens group LG2 at the wide end, and a large distance between the first lens group LG1 and the second lens at the telephoto end. The group LG2 moves in the approaching direction of each other, and the interval decreases. Such a change in the air gap between the first lens group LG1 and the second lens group LG2 is given by the locus of the second group guide cam groove 11a and the first group guide cam groove 11b. In the zoom region (zooming use region) between the tele end and the wide end, the cam ring 11, the third outer cylinder 15, and the helicoid ring 18 perform only the above-described fixed position rotation, and do not advance or retreat in the optical axis direction.

  In the zoom region, by driving the AF motor 160 according to the subject distance, the third lens group LG3 (AF lens frame 51) moves along the photographing optical axis Z1 to perform focusing.

  When the zoom motor 150 is driven in the lens barrel storage direction, the zoom lens barrel 71 performs a storage operation reverse to that at the time of the above-described extension, and is stored in the camera body 72 completely (FIG. 7). Moved to During the movement to the storage position, the second group lens frame 6 is rotated to the storage retracting position by the cam projection 21a, and retracts together with the second group lens movement frame 8. When the zoom lens barrel 71 is moved to the storage position, the second lens group LG2 is stored at the same position in the optical axis direction as the third lens group LG3 and the low-pass filter LG4 (overlaps in the radial direction of the barrel). . The retracted structure of the second lens group LG2 during storage makes it possible to shorten the storage length of the zoom lens barrel 71 and reduce the thickness of the camera body 72 in the left-right direction in FIG.

  The digital camera 70 includes a zoom finder linked to the zoom lens barrel 71. The zoom finder obtains power from the helicoid ring 18 by meshing the finder gear 30 with the spur gear portion 18c. When the helicoid ring 18 performs the above-described fixed position rotation in the zoom region, the finder gear receives the rotational force and receives the power. 30 rotates. The finder optical system has an objective window 81a, a first movable variable power lens 81b, a second movable variable power lens 81c, a prism 81d, an eyepiece 81e, and an eyepiece window 81f, and has first and second movable variable power. Zooming is performed by moving the lenses 81b and 81c along a predetermined locus along the optical axis Z3 of the finder objective system. The optical axis Z3 of the finder objective system is parallel to the photographing optical axis Z1. The holding frames 83 and 84 of the movable variable power lenses 81b and 81c are guided by guide shafts 85 and 86 (see FIGS. 6 and 7 so as to overlap and appear as one) so as to be movable in the direction of the optical axis Z3, and The moving force is given by a cam gear 90 (FIG. 5) rotatable about a rotation center axis parallel to the optical axis Z3. A reduction gear train is provided between the cam gear 90 and the finder gear 30. When the finder gear 30 rotates, the cam gear 90 is rotated, and as a result, the movable zoom lenses 81b and 81c move forward and backward. The above components of the zoom finder are sub-assembled as a finder unit 80 shown in FIG.

[Description of Characteristic Features of the Present Invention]
In the zoom lens barrel 71, a first outer cylinder (outer movable ring) 12 that supports a first lens group (first optical element, movable lens group) LG1, and a second lens group (second optical element, movable lens) FIG. 20 to FIG. 22 are cross-sectional views of a rectilinear guide structure for linearly guiding the second group lens moving frame (inner movable ring) 8 supporting the (group) LG2 in the optical axis direction. 20 shows the wide end, FIG. 21 shows the tele end, and FIG. 22 shows the stored state. In these cross-sectional views, only the members related to the straight running guide are hatched, but only the cam ring 11 of the rotating members is hatched with broken lines to make it easier to see. Are actually located at different positions in the circumferential direction, but there are some places on the same cross section for drawing.

  As can be seen from FIGS. 20 to 22, the cam ring 11 has a first group guide cam groove 11 b on the outer peripheral surface for giving a predetermined movement trajectory to the first outer cylinder 12, This is a double-sided cam groove type cam ring having a second group guide cam groove 11a on the inner peripheral surface for giving the movement locus of the second group. Accordingly, the first outer cylinder 12 is located outside the cam ring 11 in the radial direction of the lens barrel, and the second lens group moving frame 8 is located inside the cam ring 11. On the other hand, a linear guide ring (common linear guide ring) 14 for linearly guiding the first outer cylinder 12 and the second lens group moving frame 8 is located outside the cam ring 11.

  In the present embodiment, a straight guide member for the first outer cylinder 12 is used as a straight guide structure between the straight guide ring 14, the first outer cylinder 12, and the second group lens moving frame 8 in such a positional relationship. A second outer cylinder (first straight guide ring, first straight guide transmission member) 13 and a second group straight guide ring (second straight guide ring, second straight guide member) for the second group lens moving frame 8; ) Are guided directly by the straight guide ring 14. The second outer cylinder 13 is located between the cam ring 11 and the straight guide ring 14 in the radial direction, and has six straight guide projections 13a provided on the outer peripheral surface thereof corresponding to the first straight guide grooves (straight guide grooves). , The second linear guide groove) 14f to engage the linear guide by the linear guide ring 14, and engage the linear protrusions 12a with the linear guide grooves 13b formed at three places on the inner peripheral surface. The engagement guides the linear movement of the first outer cylinder 12. On the other hand, the second group straight guide ring 10 has a ring portion 10b for transferring the straight guide from the straight guide ring 14 located outside the cam ring 11 to the second group lens moving frame 8 located inside the cam ring 11. Three crotch-shaped projections (straight guides) which are located behind the cam ring 11 and engage with second straight guide grooves (straight guide portions, first straight guide grooves) 14g from the ring portion 10b toward the outer radial direction. The protrusion 10a is extended, and three rectilinear guide keys 10c engaging with the rectilinear guide grooves 8a are extended forward from the inner diameter of the ring portion 10b in the optical axis direction.

  The same conditions as in the present embodiment, that is, there are two movable elements (first outer cylinder 12, second-group lens moving frame 8) which receive rectilinear guidance on the outside and inside of the double-sided cam groove type cam ring (11), respectively. In the case where the reference straight guide member (the straight guide ring 14) is outside the cam ring, the conventional lens barrel has a sub-straight guide member (the book guide) that is guided straight by the reference straight guide member. A second outer cylinder 13 of the embodiment) is provided outside the cam ring, and a movable element (corresponding to the first outer cylinder 12) guided straight by the sub-straight guide member on the outer side is provided with a movable element inside the cam ring. A straight-moving guide for guiding the element (corresponding to the second-group lens moving frame 8) straight is provided. In other words, the straight guide is transferred from the outside to the inside of the cam ring by a single route. In such a straight guide structure, when the relative movement speed in the optical axis direction between the movable element on the outer side of the cam ring and the movable element on the inner side is high, the resistance for the straight guide may increase. In addition, since the straight guide of the movable element located inside the cam ring is performed indirectly via the outer movable element, it is particularly difficult to straightly guide the movable element inside the cam ring with high precision.

  On the other hand, in the zoom lens barrel 71 of the present embodiment, the second outer cylinder 13 for guiding the first outer cylinder 12 outside the cam ring in a straight line and the second group lens moving frame 8 inside the cam ring for straight movement are guided. The two groups of straight guide rings 10 for engagement with the straight guide grooves 14f and 14g of the straight guide ring 14 so that the two groups receive the straight guide directly from the common straight guide ring 14. Since the linear guide structure has a shape like a straight line, the above-described problems can be avoided. On the other hand, the linear guide ring 14 for simultaneously providing linear guidance to the two members of the second group linear guide ring 10 and the second outer cylinder 13 is opposite to the second group linear guide ring 10 due to the engagement relationship for the linear guide. And the second outer cylinder 13 is reinforced by the two members, so that the strength can be easily secured. In particular, since the rectilinear guide ring 14 has a roller guide through groove 14e that penetrates in the radial direction, it is a member whose actual peripheral area is smaller than the diameter size. It is effective to use it to secure the strength.

  In the linear guide ring 14, a first linear guide groove 14f for linearly guiding the second group linear guide ring 10 and a second linear guide groove 14g for linearly guiding the second outer cylinder 13 are respectively positioned in the circumferential direction. The first linear guide grooves 14f are formed as a pair of parallel grooves adjacent to both sides of the second linear guide grooves 14g. That is, each first straight guide groove 14f is formed using both side walls of the second straight guide groove 14g. This simplifies the structure of the straight guide portion, and makes it less likely that the strength of the straight guide ring 14 alone will be impaired.

  As described above, the present invention has been described based on the illustrated embodiment, but the present invention is not limited to this embodiment. For example, in the illustrated embodiment, the second linear guide groove 14g and the first linear guide groove 14f for linearly guiding the second group linear guide ring 10 and the second outer cylinder 13 are separate grooves, but the common linear guide is used. It is also possible to guide the straight running of the two straight running guide rings by the groove.

  In addition, the shape of the engaging portion in the straight guide structure can be set arbitrarily. For example, the crotch-shaped protrusion 10a of the second-group straight guide ring 10 in the embodiment is a projection projecting outward in the radial direction from the ring portion 10b when viewed as a whole second-group straight guide ring 10, The center of the tip of the projection 10a is concave. Correspondingly, on the side of the linear guide ring 14 where the crotch-shaped projection 10a engages, the first linear guide groove 14f is a concave groove when viewed individually, but as shown in FIG. It can also be considered that a trapezoidal cross-section convex rail portion that engages with the tip concave portion of 10a is formed between the pair of first rectilinear guide grooves 14f. That is, the rectilinear guide portion formed on the inner peripheral surface of the rectilinear guide ring 14 may have a groove shape or a convex rail shape.

Further, the present invention is particularly suitable for a lens barrel having a double-sided cam ring such as the cam ring 11, but it does not matter whether or not there is a cam ring, or the specific arrangement or mode of the cam ring.

FIG. 1 is an exploded perspective view of a zoom lens barrel to which the present invention is applied. FIG. 2 is an exploded perspective view of elements related to a support mechanism of a first lens group in the zoom lens barrel in FIG. 1. FIG. 2 is an exploded perspective view of elements related to a support mechanism of a second lens group in the zoom lens barrel in FIG. 1. FIG. 2 is an exploded perspective view of elements related to a feeding mechanism from a fixed ring to a third outer cylinder in the zoom lens barrel in FIG. 1. FIG. 2 is a perspective view of a completed state in which a zoom motor and a finder unit are added to the zoom lens barrel of FIG. 1. FIG. 2 is a longitudinal sectional view showing a use state of a camera equipped with a zoom lens barrel to which the present invention is applied, at a wide end and a telephoto end. FIG. 3 is a longitudinal sectional view of the camera in a lens barrel stored state. FIG. 4 is a developed plan view of a fixed ring. FIG. 3 is a developed plan view of a helicoid ring. FIG. 3 is an exploded plan view showing components on the inner peripheral surface side of the helicoid ring in a see-through manner. It is a development top view of the 3rd outer cylinder. FIG. 4 is a developed plan view of a straight guide ring. FIG. 4 is a developed plan view of a cam ring. FIG. 7 is an exploded plan view showing the second group guide cam groove on the inner peripheral surface side of the cam ring in a see-through manner. FIG. 4 is a developed plan view of a straight guide ring. FIG. 5 is a developed plan view of a second group lens moving frame. It is a development top view of a 2nd outer cylinder. FIG. 4 is a developed plan view of a first outer cylinder. FIG. 3 is a diagram conceptually illustrating an operation relationship of main components of the zoom lens barrel according to the embodiment. FIG. 3 is an upper half sectional view showing a straight-ahead guide structure at a wide end of the zoom lens barrel according to the embodiment. FIG. 3 is an upper half sectional view showing a straight-ahead guide structure at a telephoto end of a zoom lens barrel. FIG. 3 is an upper half cross-sectional view showing a rectilinear guide structure in a stored state of the zoom lens barrel. FIG. 6 is a perspective view showing a relationship between a first outer cylinder and a second-group straight-moving guide ring positioned with a cam ring interposed therebetween, and showing the straight-moving guide ring removed and viewed obliquely from the front. FIG. 24 is a perspective view showing a state in which a straight guide ring is added to FIG. 23 and the first outer cylinder is extended to a lens barrel disassembly position, as viewed from obliquely forward. It is the perspective view which looked at the state of FIG. 23 from diagonally back.

Explanation of reference numerals

A Aperture LG1 First lens group (first optical element, movable lens group)
LG2 second lens group (second optical element, movable lens group)
LG3 Third lens group LG4 Low-pass filter S Shutter Z0 Lens barrel center axis Z1 Photographing optical axis Z2 Retracting optical axis Z3 Optical axis of viewfinder objective system 1 Group lens frame 1a Male adjustment screw 2 Group adjustment ring 2a Female adjustment screw 2b Guide Projection 2c Engagement claw 3 First group retaining ring 3a Spring receiving section 6 Second group lens frame 8 Second group lens moving frame (inside movable ring)
8a Straight guide groove 8b Second group cam follower 8b-1 Front cam follower 8b-2 Rear cam follower 10 Second group straight guide ring (second straight guide ring, second straight guide transmission member)
10a crotch projection (straight guide projection)
10b Ring part 10c Straight guide key 11 Cam ring (double-sided cam ring)
11a second group guide cam groove 11a-1 front cam groove 11a-2 rear cam groove 11b first group guide cam groove 11c 11e circumferential groove 11d barrier drive ring pressing surface 12 first outer cylinder (outer movable ring)
12a Engagement projection (straight guide projection)
12b 1st group adjusting ring guide groove 13 2nd outer cylinder (1st straight running guide ring, 1st straight running guide transmission member)
13a Straight guide projection 13b Straight guide groove 13c Inner diameter flange 14 Straight guide ring 14a Straight guide projection 14b Relative rotation guide projection 14c Relative rotation guide projection 14d Circumferential groove 14e Roller guide through groove 14e-1 Circumferential groove 14e-2 Direction groove 14e-3 Lead groove 14f First straight guide groove (straight guide section, second straight guide groove)
14g Second straight guide groove (straight guide section, first straight guide groove)
15 Third outer cylinder 15a Rotation transmitting protrusion 15b Fitting protrusion 15c Spring contact recess 15d Relative rotation guide protrusion 15e Circumferential groove 15f Roller fitting groove 17 Roller urging spring 17a Roller pressing piece 18 Helicoid ring 18a Male helicoid 18b Rotation Sliding protrusion 18c Spur gear portion 18d Rotation transmitting recess 18e Fitting recess 18f Spring insertion recess 18g Circumferential groove 21 CCD holder 21a Cam protrusion 22 Fixed ring 22a Female helicoid 22b Straight guide groove 22c Slant groove 22d Rotation sliding groove 22e Stopper insertion Detachment hole 22z Front annular region 24 First group urging spring 25 Separating direction urging spring 26 Disassembly stopper 28 Zoom gear 29 Zoom gear shaft 30 Finder gear 31 First group roller 32 Cam ring roller 32a Roller fixing screw 33 Second group rotating shaft 35 times Motion control pin 36 37 2nd lens frame support plate 38 Axis Direction pressing spring 39 2nd lens frame return spring 51 AF lens frame (3rd lens frame)
52 53 AF guide shaft 54 AF nut 55 AF frame biasing spring 60 CCD (solid-state image sensor)
61 packing 62 CCD base plate 64 retaining ring fixing screw 66 support plate fixing screw 70 digital camera 71 zoom lens barrel 72 camera body 73 filter holder 74 reduction gear box 75 lens drive control FPC board 76 shutter unit 77 exposure control FPC board 80 finder Unit 81a Objective window 81b 81c Movable zoom lens 81d Prism 81e Eyepiece 81f Eyepiece window 83 84 Holding frame 85 86 Guide shaft 90 Cam gear 101 Barrier cover 102 Barrier pressing plate 103 Barrier drive ring 104 105 Barrier blade 106 Barrier spring 107 Barrier Drive ring biasing spring 140 Control circuit 150 Zoom motor 160 AF motor

Claims (14)

An outer movable ring supporting the first optical element;
An inner movable ring positioned radially inward of the outer movable ring and supporting the second optical element;
A first linear guide ring that guides the outer movable ring in the optical axis direction;
A second rectilinear guide ring for guiding the inner movable ring rectilinearly in the optical axis direction; and a rectilinear guide portion parallel to the optical axis with which the first and second rectilinear guide rings are slidably engaged. Non-rotatable common straight guide ring on the surface;
A linear guide mechanism for a lens barrel, comprising: 2. The linear guide mechanism for a lens barrel according to claim 1, wherein the first linear guide ring is located radially outside the outer movable ring, and the shared linear guide ring is located radially outside the first linear guide ring. A linear guide mechanism for the located lens barrel. 3. The linear guide mechanism for a lens barrel according to claim 1, wherein the shared linear guide ring includes at least a pair of linear guide portions with which the first linear guide ring and the second linear guide ring individually engage. Linear guide mechanism for the lens barrel. 4. The linear guide mechanism for a lens barrel according to claim 3, wherein the first linear guide ring includes at least one first linear guide protrusion that protrudes in an outer radial direction, and the second linear guide ring includes an outer radial direction. At least one second rectilinear guide projection projecting from
The rectilinear guide portion of the common rectilinear guide ring includes a first rectilinear guide groove parallel to the optical axis with which the rectilinear guide protrusion of the first rectilinear guide ring is slidably engaged, and a rectilinear movement of the second rectilinear guide ring. A rectilinear guide mechanism for a lens barrel including at least one second rectilinear guide groove parallel to the optical axis with which the guide protrusion is slidably engaged. 5. The linear guide mechanism for a lens barrel according to claim 4, wherein a plurality of said first linear guide grooves and a plurality of said second linear guide grooves are provided at different positions in the circumferential direction. . 6. The lens barrel according to claim 4, wherein one of the first straight guide groove and the second straight guide groove is provided as a pair at both circumferential positions sandwiching the other. Straight-ahead guidance mechanism. 7. The linear guide mechanism for a lens barrel according to claim 6, wherein one of the first linear guide protrusion and the second linear guide protrusion straddles the other linear guide groove with respect to the pair of linear guide grooves. A linear guide mechanism for the lens barrel engaged at the same time. The linear guide mechanism for a lens barrel according to any one of claims 1 to 7, wherein the first linear guide ring has at least one linear guide groove parallel to an optical axis on an inner peripheral surface, A linear guide mechanism for a lens barrel, wherein the outer movable ring has at least one linear guide protrusion slidably engaged with the linear guide groove on the outer peripheral surface. 9. The straight guide mechanism for a lens barrel according to claim 1, wherein the second straight guide ring has at least one straight guide key extending in a direction parallel to the optical axis. The linearly movable guide mechanism of the lens barrel, wherein the inner movable ring has at least one linearly movable guide groove in which the linearly movable guide key is slidably engaged. The linear guide mechanism for a lens barrel according to any one of claims 1 to 9, further comprising a double-sided cam ring having at least one cam groove on both the outer peripheral surface and the inner peripheral surface,
The outer movable ring is located radially outward of the double-sided cam ring, and has at least one cam follower that engages with an outer-side cam groove of the double-sided cam ring.
A linearly-moving guide mechanism for a lens barrel, wherein the inner movable ring is located radially inward of the cam ring and has at least one cam follower engaged with an inner surface cam groove of the double-sided cam ring. 11. The linear guide mechanism for a lens barrel according to claim 10, wherein the second linear guide ring is supported by the rear end of the double-sided cam ring in the optical axis direction so as to be relatively rotatable and relatively immovable in the optical axis direction. A linear guide mechanism for a lens barrel having a ring portion. The linear guide mechanism for a lens barrel according to any one of claims 1 to 11, further comprising a fixed ring that does not move, wherein the shared linear guide ring is supported by the fixed ring so as to be able to linearly move in the optical axis direction. Linear guide mechanism for the lens barrel. 13. The linear guide mechanism for a lens barrel according to claim 10, wherein the first optical element supported by the outer movable ring and the second optical element supported by the inner movable ring are movable. A lens group, wherein the first and second movable lens groups move along a predetermined trajectory in the optical axis direction in accordance with the rotation of the double-sided cam ring; Double-sided cam ring having cam grooves on both the outer peripheral surface and the inner peripheral surface;
An outer movable ring supporting a first optical element, the outer movable ring having a cam follower positioned radially outward of the double-sided cam ring and engaging with a cam groove on an outer peripheral surface of the double-sided cam ring;
An inner movable ring supporting a second optical element, the inner movable ring having a cam follower located radially inward of the double-sided cam ring and engaging with a cam groove on an inner peripheral surface of the double-sided cam ring;
A non-rotatable shared linear guide ring which is located radially outside of the double-sided cam ring and has a linear guide portion parallel to the optical axis on its inner peripheral surface; and each of the shared linear guide rings directly emits light. First and second linear guide transmitting members that are guided linearly in the axial direction and respectively guide the outer movable ring and the inner movable ring individually linearly in the optical axis direction;
A linear guide mechanism for a lens barrel, comprising:

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