JP2004151243A - Rotating-extending mechanism for lens barrel and rotating-extending mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate backlash between a follower projection and its guide part in the rotation transfer mechanism for a lens barrel or the like. <P>SOLUTION: The mechanism is equipped with a rotation transfer ring having a plurality of rotation transfer grooves parallel with an optical axis on its inner peripheral surface, an extending guide ring having a plurality of through-lead grooves inclined in an optical axis direction and a peripheral direction and a plurality of through-peripheral direction grooves communicating with the lead grooves and positioned inside the rotation transfer ring, a movable ring having a plurality of follower projections engaged in the rotation transfer grooves so as not to relatively move in a rotating direction but to slide in the optical axis direction, and a ring spring having a plurality of follower pressing parts fit in the respective rotation transfer grooves, supported on the inner peripheral surface of the rotation transfer ring and elastically deformed in the optical axis direction. The follower projections are separated from the follower pressing parts of the ring spring at relative positions where they are engaged in the lead grooves, and abut on the follower pressing parts at relative positions where they are engaged in the through-peripheral direction grooves, whereby the ring spring is elastically deformed. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
【Technical field】
The present invention relates to a rotary feeding mechanism such as a lens barrel.
[0002]
[Prior art and its problems]
The following is known as a mechanism for rotating a movable ring such as a cam ring and extending the lens barrel forward in a lens barrel. A rotation transmission groove in the optical axis direction is formed in the rotation transmission ring rotated by the motor, and the follower protrusion of the movable ring is engaged with the rotation transmission groove so as to be movable only in the optical axis direction. The follower projections are simultaneously engaged with lead grooves formed in the non-rotating feeding guide ring. The lead groove includes both a circumferential component and an optical axis direction component.When a rotational force is applied to the follower projection via the rotation transmission ring, the movable ring rotates along the lead groove and moves in the optical axis direction. Moving. In such a structure, it is necessary to remove the backlash between the follower projection and its guide groove (lead groove) in the photographing state in order to increase the positional accuracy of the movable element such as the lens group in the optical axis direction. The structure tended to be complicated.
[0003]
[Object of the invention]
An object of the present invention is to apply a rotation transmission mechanism such as a lens barrel which has a simple and compact structure and can remove backlash between a follower projection and its guide.
[0004]
Summary of the Invention
The rotation transmission mechanism of the lens barrel of the present invention includes: a rotation transmission ring having a plurality of rotation transmission grooves parallel to the optical axis on an inner peripheral surface; a plurality of through lead grooves including both an optical axis direction component and a circumferential direction component; A plurality of through-circumferential grooves consisting only of circumferential components communicating with the through-lead grooves, and a feed-out guide ring located inside the rotation transmission ring; Movable ring having a plurality of follower protrusions engaged with the rotation transmission groove so as to be relatively immovable in the rotational direction and slidably in the optical axis direction with respect to the rotation transmission groove; and an optical axis on the inner peripheral surface of the rotation transmission ring. A ring spring having a plurality of follower pressing portions fitted in each of the plurality of rotation transmitting grooves, the movable ring engaging a plurality of follower protrusions with the through lead grooves; At the relative position of the ring in the optical axis direction, the follower protrusion is At a relative position in the optical axis direction between the movable ring and the rotation transmission ring, which are separated from the follower pressing portion of the spring and the plurality of follower protrusions are engaged with the through circumferential groove, the follower protrusion abuts on the follower pressing portion to form a ring. The spring is elastically deformed, and the follower protrusion is pressed in the optical axis direction by the ring spring and pressed against one of the sliding guide surfaces of the through circumferential groove. According to this structure, the backlash between the movable ring and the feeding guide ring can be easily and compactly removed.
[0005]
The rotation feeding mechanism of the lens barrel of the present invention further includes a rotation permitting coupling portion that couples the rotation transmission ring and the feeding guide ring so as to be relatively rotatable with each other, and in a coupling state via the rotation permitting coupling portion, It is preferable that the feeding guide ring is brought into contact with the ring spring and elastically deformed so as to be pressed in the optical axis direction by its restoring force. With this configuration, the ring spring can remove not only the backlash between the movable ring and the feeding guide ring but also the backlash between the rotation transmission ring and the feeding guide ring.
[0006]
The ring spring is, for example, a plurality of the follower pressing portions provided at different positions in the circumferential direction, and a partial annular portion connecting the plurality of follower pressing portions and projecting in a free shape in a direction parallel to the optical axis in a mountain shape. It is good to comprise so that it may have.
[0007]
The movable ring can be, for example, a cam ring having a cam groove that gives a predetermined movement locus to the plurality of movable lens groups in the optical axis direction by rotation.
[0008]
The present invention is preferably applied to a lens barrel that is in a non-photographing state when the follower protrusion engages with the through lead groove and is in a photographing state when engaging with the through circumferential groove.
[0009]
The present invention can also be applied to a rotary extension mechanism other than a lens barrel.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
[Overall description of lens barrel]
First, the overall structure of the zoom lens barrel 71 of the present embodiment will be described with reference to FIGS. This embodiment is an embodiment in which the present invention is applied to a zoom lens barrel for a digital camera 70. The photographing optical system includes a first lens group LG1, a shutter S and an aperture A, and a second lens in order from the object side. The optical system includes a group LG2, a third lens group LG3, a low-pass filter (filters) LG4, and a solid-state imaging device (CCD) 60. The optical axis of the photographing optical system is Z1. The imaging optical axis Z1 is parallel to the center axis Z0 of the zoom lens barrel 71 and is eccentric with respect to the center axis Z0 of the lens barrel. The 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 the 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.
[0011]
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 solid-state imaging device 60 is supported on the CCD holder 21 via a CCD base plate 62, and a low-pass filter LG 4 is supported on the front of the solid-state imaging device 60 via a filter holder 73 and packing 61.
[0012]
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. In each case, a guide hole formed in the AF lens frame 51 is slidably fitted. In the present embodiment, the AF guide shaft 52 is a main guide shaft, and the AF guide shaft 53 is provided for restricting the rotation of the AF lens frame 51. A feed screw formed on the drive shaft of the AF motor 160 is screwed to the AF nut 54 fixed to the AF lens frame 51. When the drive shaft is rotated, the feed screw and the AF nut 54 are screwed together. The AF lens frame 51 is moved forward and backward in the optical axis direction. The AF lens frame 51 is biased forward by an AF frame biasing spring 55 in the optical axis direction.
[0013]
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 via a lens drive control FPC (flexible printed circuit) board 75 disposed on the outer peripheral surface of the fixed ring 22.
[0014]
On the inner peripheral surface of the fixed ring 22, a female helicoid 22a, three rectilinear guide grooves 22b parallel to the imaging optical axis Z1, three lead grooves 22c parallel to the female helicoid 22a, and a front end of each lead groove 22c 22d is formed with a circumferential rotational sliding groove 22d communicating with the groove. The female helicoid 22a is not formed in a part of the front portion of the fixed ring 22 where the rotary sliding groove 22d is formed (see FIG. 8).
[0015]
The helicoid ring 18 has a male helicoid 18a screwed to the female helicoid 22a and a rotary sliding projection 18b engaged with the lead groove 22c and the rotary sliding groove 22d on the outer peripheral surface (FIGS. 4 and 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. Therefore, when a rotational force is applied by the zoom gear 28, 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 screwed relationship, and when the helicoid ring 18a moves forward to some extent, the male helicoid 18a Is disengaged from the female helicoid 22a, and performs only circumferential rotation about the lens barrel center axis Z0 due to the engagement between the rotary sliding groove 22d and the rotary sliding protrusion 18b. In the female helicoid 22a, a pair of helicoid peaks sandwiching each lead groove 22c has a circumferential interval larger than that of the other helicoid peaks, and the male helicoid 18a has a helicoid peak having a wide circumferential pitch. The three helicoid peaks 18a-W located behind the rotary sliding protrusion 18b are circumferentially wider than the other helicoid peaks (FIGS. 8 and 9). A stopper insertion / removal hole 22e is formed in the fixed ring 22 so as to penetrate the rotary sliding groove 22d and the outer peripheral surface. The stopper insertion / removal hole 22e is provided to restrict the rotation of the helicoid ring 18 beyond the photographing area. Lens barrel stopper 26 is detachable.
[0016]
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. Further, the helicoid ring 18 is formed with a fitting recess 18e by cutting out a part of the rotation sliding protrusion 18b on the inner diameter side, and the fitting protrusion 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 zoom lens barrel in FIG. 6).
[0017]
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 on the extension of the optical axis. 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.
[0018]
On the inner peripheral surface of the third outer tube 15, a relative rotation guide protrusion 15d protruding in the inner diameter direction, a circumferential groove 15e centered on the lens barrel center axis Z0, and a third groove parallel to the photographing optical axis Z1. The roller fitting groove 15f is 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. On the outer peripheral surface of the rectilinear guide ring 14, in order from the rear in the optical axis direction, three rectilinear guide protrusions 14a protruding in the radial direction, and a plurality of relative rotation guide protrusions 14b provided at different positions in the circumferential direction, 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 grooves 15e and 14d and the relative rotation guide protrusions 14c and 15d are loosely fitted so as to be relatively movable in the optical axis direction. Further, the helicoid ring 18 is also 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.
[0019]
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 roller guide through groove 14e includes front and rear parallel circumferential grooves 14e-1 and 14e-2 formed in the circumferential direction, and both circumferential grooves 14e-1 and 14e-2. And a lead groove 14e-3 parallel to the female helicoid 22a. 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). The backlash between the groove 14e-1) is removed.
[0020]
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 by the engagement relationship between the circumferential grooves 14d, 15e and 18g and the relative rotation guide projections 14b, 14c and 15d, 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 in 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 rotationally extended portion 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.
[0021]
The above-mentioned feeding operation is performed in a state where the male helicoid 18a is screwed with the female helicoid 22a. At this time, the rotary sliding projection 18b is moving in the lead groove 22c. When the male helicoid 18a and the female helicoid 22a are disengaged from each other by a predetermined amount by the helicoid, the rotary sliding protrusion 18b enters the rotary sliding groove 22d from the lead groove 22c. At the same time, the cam ring roller 32 enters the circumferential groove 14e-1 of the roller guide through groove 14e. Then, the helicoid ring 18 and the third outer cylinder 15 do not act on the rotation output by the helicoid, so that only the rotation is performed at a fixed position in the optical axis direction according to the driving of the zoom gear 28. In this state, the straight guide ring 14 stops, and the cam ring roller 32 moves into the circumferential groove 14e-1, so that no forward moving force is applied to the cam ring 11, and the cam ring 11 is moved to the third outer position. Only rotation is performed at a fixed position in accordance with the rotation of the cylinder 15.
[0022]
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.
[0023]
The structure prior to the cam ring 11 will be further 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.
[0024]
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.
[0025]
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 10c has a pair of guide surfaces parallel to the photographing optical axis Z1 on the side surface. 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.
[0026]
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 base locus α. The front cam groove 11a-1 and the rear cam groove 11a-2 differ from each other in 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. The lens barrel use region is, in other words, a region in which the movement can be controlled by the cam mechanism, and is used to distinguish it from the assembly and disassembly region of the cam mechanism. 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. In a case where the pair of front cam grooves 11a-1 and rear cam grooves 11a-2 are formed as one group, three groups of second group guide cam grooves 11a are formed at equal intervals in the circumferential direction.
[0027]
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 follower 8b is also provided with a pair of a front cam follower 8b-1 and a rear cam follower 8b-2 whose positions are different in the optical axis direction and the circumferential direction as a group and is equally spaced in the circumferential direction. The front cam follower 8b-1 is engaged with the front cam groove 11a-1, and the rear cam follower 8b-2 is engaged with the rear cam groove 11a-2 in the optical axis direction. A circumferential interval is defined.
[0028]
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.
[0029]
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 shaft 33 is parallel to the imaging optical axis Z1 and is eccentric with respect to the imaging optical axis Z1, and the second lens group frame 6 has the second lens group LG2 around the second group rotation axis 33 as the rotation center. Can be rotated to a photographing position (FIG. 6) where the optical axis Z2 of the second lens unit coincides with the photographing optical axis Z1 and a retracting position for storage (FIG. 7) where the second group optical axis Z2 is eccentric from the photographing optical axis Z1. . 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.
[0030]
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.
[0031]
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.
[0032]
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.
[0033]
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 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.
[0034]
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. At the front and rear positions of the shutter unit 76, two actuators (not shown) for driving the shutter S and the aperture A are respectively arranged one by one, and these actuators are transmitted from the shutter unit 76 to the control circuit of the camera. An exposure control FPC (flexible printed circuit) board 77 for connection is extended.
[0035]
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).
[0036]
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.
[0037]
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 body 72 has a flat shape in which the zoom lens barrel 71 does not protrude. When the zoom gear 28 is rotationally driven in the feeding direction by the zoom motor 150 from the lens barrel storage state, the combined body of the helicoid ring 18 and the third outer cylinder 15 is rotated and fed according to 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.
[0038]
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. 7, the second group lens frame 6 in the second group lens moving frame 8 has its second group optical axis Z2 eccentric from the photographing optical axis Z1 by the action of the cam projection 21a protruding from the CCD holder 21. The second group lens frame 6 is separated from the cam projection 21a while the second group lens moving frame 8 is being extended to the zoom region, and the urging force of the second group lens frame returning spring 39 is held. As a result, the second group optical axis Z2 is rotated to the photographing position (FIG. 6) where the second group optical axis Z2 coincides 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.
[0039]
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.
[0040]
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.
[0041]
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.
[0042]
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.
[0043]
The digital camera 70 includes a zoom finder that works in conjunction with 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 of the movable variable power lenses 81b and 81c are guided linearly by the guide shaft 82 so as to be movable in the direction of the optical axis Z3, and receive driving force from a shaft screw parallel to the guide shaft 82. A reduction gear train is provided between the shaft screw and the finder gear 30. When the finder gear 30 rotates, the shaft screw rotates, and the movable zoom lenses 81b and 81c advance and retreat. The above components of the zoom finder are sub-assembled as a finder unit 80 shown in FIG.
[0044]
[Description of Characteristic Features of the Present Invention]
As described above, when a rotational force is applied to the cam ring roller (follower projection) 32 through the roller fitting groove 15f of the third outer cylinder (rotation transmission ring) 15, the distance between the lens barrel storage state and the wide end is reduced. In the above, the cam ring (movable ring) 11 rotates and moves in the optical axis direction by the cam ring roller 32 being guided by the lead groove portion (through lead groove) 14e-3 of the rectilinear guide ring (extending guide ring) 14. In the zoom region, the cam ring roller 32 engages with the circumferential groove (through circumferential groove) 14e-1, and the cam ring 11 rotates in a fixed position without moving in the optical axis direction. Since the photographing is performed when the cam ring 11 rotates at a fixed position, the position of the cam ring 11 in the optical axis direction is accurately determined in order to secure the optical accuracy of the movable lens groups such as the first lens group LG1 and the second lens group LG2. There is a need. The position of the cam ring 11 in the optical axis direction at the time of rotation at the fixed position is determined by the fitting relationship between the cam ring roller 32 and the circumferential groove 14e-1, but there is a smooth gap between the cam ring roller 32 and the circumferential groove 14e-1. There is clearance to allow sliding. Therefore, in order to eliminate the displacement of the cam ring 11 (cam ring roller 32) in the optical axis direction due to the clearance, it is necessary to perform so-called backlash removal.
[0045]
As shown in FIGS. 20 to 29, a roller biasing spring (ring spring) 17 for removing backlash between the cam ring roller 32 and the circumferential groove 14e-1 is held inside the third outer cylinder 15. Have been. In FIGS. 20 to 27, for the straight guide ring 14, the roller biasing spring 17, and the cam ring roller 32, the regions located behind the third outer cylinder 15 are also indicated by solid lines (FIG. 24 to FIG. 24). Only the straight guide ring 14 in FIG. 27 is shown by a two-dot chain line). On the inner peripheral surface of the third outer cylinder 15, an annular inner flange 15g is formed at the forefront in the optical axis direction. As shown in FIG. 23, the roller biasing spring 17 is a non-planar annular body having a plurality of bent portions in a direction parallel to the optical axis, and is elastically deformable in the optical axis direction. . More specifically, the roller biasing spring 17 has three roller pressing pieces (follower pressing portions) 17a located rearmost in the optical axis direction, and projects forward between the roller pressing pieces 17a in the optical axis direction. It has two chevron annular portions 17b. The chevron-shaped annular portion 17b engages with the inner flange 15g and the relative rotation guide protrusion 15d in a state of being slightly contracted in the optical axis direction, and the falling off from the third outer cylinder 15 is regulated. When the angular portion 17b is fitted between the inner flange 15g and the relative rotation guide projection 15d in a state where the phases of the roller pressing pieces 17a and the roller fitting grooves 15f in the rotational direction are matched, the roller pressing pieces 17a Is held near the front end of the roller fitting groove 15f. However, in the lens barrel disassembled state, as shown in FIG. 27, the roller pressing piece 17a is separated from the inner flange 15g, and the roller pressing piece 17a can move forward in the optical axis direction in the roller fitting groove 15f. Has become.
[0046]
In the lens barrel assembled state, as shown in FIGS. 20 and 24, the front end portion of the rectilinear guide ring 14 presses the chevron annular portion 17b forward, so that the chevron annular portion 17b approaches a flat shape. As a result, the roller urging spring 17 is elastically deformed. The rectilinear guide ring 14 is pressed rearward in the optical axis direction by the restoring force of the elastically deformed roller urging spring 17, and the position of the rectilinear guide ring 14 with respect to the third outer cylinder 15 in the optical axis direction is determined. That is, the front surface in the optical axis direction of the circumferential groove (rotation-permissible coupling portion) 14d is pressed against the front end surface of the relative rotation guide protrusion (rotation-permissible coupling portion) 15d, and similarly, the relative rotation guide projection (rotation-permissible coupling portion). ) The rear end face of 14c is pressed against the rear face of the circumferential groove (rotation permitting joint) 15e. At this time, the front end of the rectilinear guide ring 14 is located between the inner flange 15g and the relative rotation guide protrusion 15d in the optical axis direction, and the roller urging spring 17 is completely adhered to the inner flange 15g. I haven't. Therefore, a slight space is secured in the optical axis direction between the roller pressing piece 17a and the inner flange 15g, and there is room for the roller pressing piece 17a to move forward in the optical axis direction by this distance. . As shown in FIGS. 24 and 28, the tip end (the rear end face in the optical axis direction) of the roller pressing piece 17a is located at a position slightly protruding inside the circumferential groove 14e-1 in the optical axis direction.
[0047]
20 and 24, the roller biasing spring 17 is not in contact with any element other than the rectilinear guide ring 14. As shown in FIGS. 20 and 24, at this time, the cam ring roller 32 is engaged with the roller fitting groove 15f similarly to the roller pressing piece 17a, but the roller is not engaged with the circumferential groove portion 14e-2. Since it is located near the rear end of the fitting groove 15f, it is separated from the roller pressing piece 17a.
[0048]
When the third outer cylinder 15 is rotated in the lens barrel extending direction from the stored state, the upward movement force in FIGS. 20 and 24 is given to the cam ring roller 32 via the roller fitting groove 15f, and The ring roller 32 moves from the circumferential groove 14e-2 into the lead groove 14e-3. Since the lead groove 14e-3 is an inclined groove containing both the circumferential component and the optical axis component, the cam ring roller 32 gradually moves forward in the optical axis direction in the roller fitting groove 15f as it advances in the lead groove 14e-3. Moving. However, while located in the lead groove 14e-3, the cam ring roller 32 is still separated from the roller pressing piece 17a. The fact that the cam ring roller 32 is separated from the roller pressing piece 17a means that the cam ring roller 32 does not receive the urging force of the roller urging spring 17. However, the engagement state between the circumferential groove portion 14e-2 and the lead groove portion 14e-3 and the cam ring roller 32 is a lens barrel storage state and a transition stage from the storage state to the photographing state, respectively. Even if backlash removal using the spring 17 is not actively performed, there is substantially no problem. Rather, since the sliding resistance acting on the cam ring roller 32 is small, the load on the zoom motor 150 can be reduced.
[0049]
When the third outer cylinder 15 continues to rotate in the feeding direction and the cam ring roller 32 moves from the inside of the lead groove 14e-3 to the inside of the circumferential groove 14e-1, the photographing state at the wide end shown in FIGS. become. As described above, since the roller pressing piece 17a has a tip portion slightly protruding inside the circumferential groove 14e-1, the cam ring roller 32 that has entered the circumferential groove 14e-1 is a roller pressing piece 17a. (See FIG. 29). Then, the roller pressing piece 17a is pushed forward in the optical axis direction by the cam ring roller 32, and the roller urging spring 17 is elastically deformed so that the angled portion annular portion 17b becomes flatter than the pressing state by the linear guide ring 14 alone. . Due to the reaction force of the elastically deformed roller urging spring 17, the cam ring roller 32 is pressed against the front and rear guide surfaces of the front and rear guide surfaces constituting the circumferential groove 14e-1. Backlash is removed.
[0050]
Further, from the wide end in FIGS. 21 and 25 to the tele end in FIGS. 22 and 26, the cam ring roller 32 moves in the circumferential groove portion 14e-1 consisting of only the circumferential component and engages with the roller. Since the cam ring roller 32 does not move in the optical axis direction in the groove 15f, the contact state between the cam ring roller 32 and the roller pressing piece 17a is maintained. That is, in the zoom range where the photographing is performed, the cam ring roller 32 continues to receive the urging force in the optical axis rearward direction by the roller urging spring 17, and the position in the optical axis direction with respect to the linear guide ring 14 is stabilized.
[0051]
When the zoom motor 150 is driven in the lens barrel storage direction, the reverse operation occurs. When the third outer cylinder 15 rotates in the storage direction, the cam ring roller 32 separates from the roller pressing piece 17a at a point past the wide end position, and thereafter the pressing force of the roller urging spring 17 until the storage state is reached. Will not receive. When the pressing force of the roller urging spring 17 stops acting, the sliding resistance against the cam ring roller 32 is reduced, so that the burden on the zoom motor 150 in the lens barrel storage operation is reduced.
[0052]
As described above, in the zoom lens barrel 71 of the present embodiment, the roller pressing piece 17a of the roller biasing spring 17 is provided at the position in the optical axis direction where the cam ring roller 32 is located in the photographing state in the roller fitting groove 15f, When the cam ring roller 32, which has been guided forward by the lead groove portion 14e-3 and has moved forward in the optical axis direction, reaches a photographing position (a fixed position rotation area), the roller urging spring 17 automatically causes the cam ring roller 32 to move. It is urged rearward in the optical axis direction and pressed against one guide surface of the circumferential groove 14e-1. According to this configuration, the backlash of the three cam ring rollers 32 and the straight guide ring 14e can be removed by a single roller urging spring 17, and the structure is simple. Further, the roller biasing spring 17 is an annular body arranged along the inner peripheral surface of the third outer cylinder 15, and the three roller pressing pieces 17a are housed in the roller fitting grooves 15f. Requires less space. Therefore, while having a simple and compact structure, the position of the cam ring 11 in the optical axis direction can be stabilized during photographing, and high optical precision can be obtained. The roller biasing spring 17 can be easily attached and detached because it only holds the angled portion annular portion 17b between the inner flange 15g and the relative rotation guide projection 15d.
[0053]
Further, the roller urging spring 17 not only urges the cam ring roller 32 to increase the position accuracy of the cam ring 11 in the optical axis direction with respect to the linear guide ring 14 but also urges the linear guide ring 14 backward in the optical axis direction. This also has a function of stabilizing the position of the rectilinear guide ring 14 in the optical axis direction with respect to the third outer cylinder 15. As shown in FIGS. 24 to 27, the relative rotation guide projection 14c and the relative rotation guide projection 15d are engaged with the circumferential groove 15e and the circumferential groove 14d, respectively, with a clearance in the optical axis direction. As described above, the front end of the rectilinear guide ring 14 abuts against the roller urging spring 17 and receives the urging force rearward in the optical axis direction by the roller urging spring 17 so that the relative rotation guide protrusion 14 c The backlash between the direction groove 15e and the relative rotation guide protrusion 15d and the circumferential direction groove 14d are respectively removed. In other words, when the three annular members of the cam ring 11, the linear guide ring 14, and the third outer cylinder 15 are regarded as a rotary feeding unit, the backlash removal in the entire rotary feeding unit is performed by a single roller biasing spring 17 Therefore, the structure is very simple.
[0054]
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, it is possible to zoom out from the stored state in FIGS. 20 and 24 to the wide end in FIGS. 21 and 25 and then zoom to the tele end in FIGS. 22 and 26. If the rotation from the wide end to the forward end is not performed, it can be applied as a single focus lens barrel.
[0055]
In the embodiment, the cam ring roller 32 and the roller guide through groove 14e are provided at three places. However, the number may be other than three.
[0056]
In addition, the present invention can be applied to a rotary feeding mechanism other than the lens barrel by setting the object supported by the movable ring to something other than an optical element such as a lens frame.
[0057]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain a rotation transmission mechanism such as a lens barrel capable of removing backlash between a follower protrusion and a guide portion thereof with a simple and compact structure.
[Brief description of the drawings]
FIG. 1 is an exploded perspective view of a zoom lens barrel to which a cam feeding mechanism according to the present invention is applied.
FIG. 2 is an exploded perspective view of a portion related to a support mechanism of a first lens group in the zoom lens barrel in FIG.
FIG. 3 is an exploded perspective view of a portion related to a support mechanism of a second lens group in the zoom lens barrel in FIG.
FIG. 4 is an exploded perspective view of a portion related to a feeding mechanism from a fixed ring to a third outer cylinder in the zoom lens barrel in FIG.
FIG. 5 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. 6 is a longitudinal sectional view of a camera equipped with the zoom lens barrel, showing a wide end and a tele end of the zoom lens barrel of FIG. 1;
FIG. 7 is a vertical sectional view of the camera in a state where the lens barrel is stored.
FIG. 8 is a plan view of a stationary ring.
FIG. 9 is a plan view of a helicoid ring.
FIG. 10 is a plan view showing components on the inner peripheral surface side of the helicoid ring in a see-through manner.
FIG. 11 is a plan view of a third outer cylinder.
FIG. 12 is a plan view of a straight traveling guide ring.
FIG. 13 is a plan view of a cam ring.
FIG. 14 is a 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. 15 is a plan view of a straight guide ring.
FIG. 16 is a plan view of a second group lens moving frame.
FIG. 17 is a plan view of a second outer cylinder.
FIG. 18 is a plan view of the first outer cylinder.
FIG. 19 is a diagram conceptually illustrating a relationship between main members of the zoom lens barrel according to the present embodiment.
FIG. 20 is a plan view showing a relationship among a helicoid ring, a third outer cylinder, and a straight guide ring in a lens barrel stored state.
FIG. 21 is a plan view showing a relationship between a helicoid ring, a third outer cylinder, and a straight guide ring at a wide end.
FIG. 22 is a plan view showing a relationship between a helicoid ring, a third outer cylinder, and a straight guide ring at the telephoto end.
FIG. 23 is a plan view showing a relationship between a helicoid ring, a third outer cylinder, and a straight guide ring in a lens barrel disassembled state.
FIG. 24 is an enlarged view of a part of FIG. 20;
FIG. 25 is an enlarged view of a part of FIG. 21;
26 is an enlarged view of a part of FIG.
FIG. 27 is an enlarged view of a part of FIG.
28 is an enlarged cross-sectional view showing a part of the upper half cross-section of the lens barrel stored state in FIG. 7;
29 is a cross-sectional view showing a part of an upper half cross section (wide end) of the photographing state in FIG. 6 in an enlarged manner.
[Explanation of symbols]
LG1 First lens group (movable lens group)
LG2 Second lens group (movable lens group)
LG3 Third lens group LG4 Low pass filter S Shutter A Aperture Z0 Lens barrel center axis Z1 Photographing optical axis Z2 Second group optical axis Z3 Optical axis 1 of finder objective system First group lens frame 1a Male adjustment screw 2 First group adjustment ring 2a Female adjustment Screw 2b Guide projection 2c Engagement claw 3 1st group retaining ring 3a Spring receiving section 6 2nd lens frame 8 2nd lens moving frame 8a Straight guide groove 8b 2nd group cam follower 8b-1 Front cam follower 8b-2 Rear cam follower 10 2nd group Linear guide ring 10a Crotch-shaped protrusion 10b Ring portion 10c Linear guide key 11 Cam ring (movable 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 12a engagement protrusion 12b first group adjustment ring guide Groove 13 Second outer cylinder 13a Straight guide projection 13b Straight guide groove 13c Inner diameter flange 14 Straight guide ring (extending guide ring)
14a Straight-travel guide protrusion 14b Relative rotation guide protrusion 14c Relative rotation guide protrusion (rotation-permissible coupling portion)
14d Circumferential groove (Rotatable joint)
14e Roller guide through groove 14e-1 Circumferential groove (penetrating circumferential groove)
14e-2 Circumferential groove 14e-3 Lead groove (through lead groove)
14f First straight guide groove 14g Second straight guide groove 15 Third outer cylinder (rotation transmission ring)
15a Rotation transmitting protrusion 15b Fitting protrusion 15c Spring-abutting recess 15d Relative rotation guide protrusion (rotation-permissible coupling portion)
15e Circumferential groove (Rotatable joint)
15f Roller fitting groove (rotation transmission groove)
15g Inner flange 17 Roller biasing spring (ring spring)
17a Roller pressing piece (follower pressing section)
17b Partial annular part of Yamagata (partial annular part)
18 Helicoid ring 18a Male helicoid 18b Rotating sliding protrusion 18c Spur gear portion 18d Rotation transmitting recess 18e Fitting recess 18f Spring inserting recess 18g Circumferential groove 21 CCD holder 21a Cam protrusion 22 Fixed ring 22a Female helicoid 22b Straight guide groove 22c Lead groove 22d Rotary sliding groove 22e Stopper insertion / removal hole 24 First group biasing spring 25 Separating direction biasing spring 26 Lens barrel stopper 28 Zoom gear 29 Zoom gear shaft 30 Finder gear 31 First group roller 32 Cam ring roller (follower projection)
32a Roller fixing screw 33 Second group rotation shaft 35 Rotation restricting pin 36 37 Second group lens frame support plate 38 Axial pressing spring 39 Second group lens frame return spring 51 AF lens frame (third group lens frame)
52 53 AF guide shaft 54 AF nut 55 AF frame biasing spring 60 Solid-state imaging device (CCD)
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 82 Guide shaft 101 Barrier cover 102 Barrier pressing plate 103 Barrier drive ring 104 105 Barrier blade 106 Barrier bias spring 107 Barrier drive ring bias spring 150 Zoom Motor 160 AF motor

Claims (6)

A rotation transmission ring having a plurality of rotation transmission grooves parallel to the optical axis on an inner peripheral surface;
A plurality of through lead grooves including both the optical axis direction component and the circumferential direction component, and a plurality of through circumferential grooves formed only of the circumferential component communicating with the through lead groove, inside the rotation transmission ring. Located feeding guide ring;
Movable having a plurality of follower projections which engage with the through-lead groove and the through-peripheral groove alternatively, and engage with the rotation transmission groove so as to be relatively immovable in the rotational direction and slidably in the optical axis direction. A ring spring having a plurality of follower pressing portions fitted into each of the plurality of rotation transmission grooves and supported on an inner peripheral surface of the rotation transmission ring and capable of being elastically deformed in the optical axis direction;
With
A lens mirror, wherein the plurality of follower projections press the movable optical axis and the lower optical axis projection of the rotation transmission ring which are engaged with the through lead groove in the optical axis direction and press against one surface of the through circumferential groove. Rotary feeding mechanism for cylinders. The rotation feeding mechanism for a lens barrel according to claim 1, wherein the rotation transmission ring and the feeding guide ring have a rotation permissible coupling portion that couples each other so as to be relatively rotatable,
A rotation guide mechanism of the lens barrel, in which the feeding guide ring abuts on the ring spring and elastically deforms in a state of being connected to the rotation transmitting ring, and is pressed in the optical axis direction by the ring spring. 3. The rotating and extending mechanism for a lens barrel according to claim 1, wherein the ring spring is connected to the plurality of follower pressing portions provided at different positions in a circumferential direction, and is connected to the plurality of follower pressing portions in a free state. 4. And a partial annular portion protruding in a mountain shape in a direction parallel to the optical axis. 4. A cam ring according to claim 1, wherein said movable ring has a cam groove for providing a predetermined movement trajectory in a direction of an optical axis to a plurality of movable lens groups by rotation. The mechanism for rotating the lens barrel. 5. The rotation extension mechanism for a lens barrel according to claim 1, wherein the follower projection is in a non-photographing state when engaging with the through-lead groove, and when the follower projection engages with the through-circumferential groove. 6. A mechanism for rotating the lens barrel for shooting. A rotation transmission ring having a plurality of rotation transmission grooves parallel to the rotation axis on an inner peripheral surface;
A plurality of through-lead grooves including both a rotation axis direction component and a circumferential direction component, and a plurality of through-peripheral grooves including only circumferential components communicating with the through-lead grooves, are provided inside the rotation transmission ring. Located feeding guide ring;
Movable having a plurality of follower projections that engage with the through lead groove and the through circumferential groove alternatively, and engage with the rotation transmission groove so as to be relatively immovable in the rotational direction and slidably in the rotational axis direction. A ring spring having a plurality of follower pressing portions fitted into each of the plurality of rotation transmission grooves and supported on an inner peripheral surface of the rotation transmission ring and capable of being elastically deformed in a rotation axis direction;
With
At a relative position in the rotation axis direction of the movable ring and the rotation transmission ring in which the plurality of follower protrusions engage with the through lead grooves, the follower protrusions are separated from the follower pressing portion of the ring spring,
At a relative position in the rotation axis direction between the movable ring and the rotation transmission ring in which the plurality of follower protrusions engage with the through circumferential groove, the follower protrusion contacts the follower pressing portion, and the ring spring is elastically deformed. The follower projection is pressed in the direction of the rotation axis by one of the plurality of projections, and is pressed against one surface of the through-circumferential groove.

Images