JP3249047B2 - Lens support structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a lens support structure.

[0002]

2. Description of the Related Art For example, in a zoom lens having a front lens group and a rear lens group, a shutter having a lens frame for holding the front lens group fixed to a movable lens barrel extended from a camera body. Some are supported by the movable barrel by being screwed into the unit, and others are directly fixed to the movable barrel. As this fixing method, screwing, an adhesive or the like has been conventionally used.

However, according to the above-mentioned method, there is a problem that adjustment at the time of assembly becomes difficult. If adjustment is not possible at the time of attachment, it may be difficult to maintain the assembly accuracy, and when a light-shielding member, a waterproof member, or the like is incorporated, it is difficult to ensure light-shielding properties, waterproofness, and the like.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a lens support structure capable of accurately setting a mounting position based on the above-mentioned problem awareness and adjusting the mounting position.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a cylindrical lens frame to which a lens is fixed, a lens support tube having a circular opening for inserting the cylindrical lens frame, and a front surface of the circular opening of the lens support tube. An outer flange formed on the cylindrical lens frame facing the peripheral edge, an O-ring sandwiched between the outer flange of the cylindrical lens frame and a front peripheral edge of the lens support cylinder, the outer peripheral surface and the lens support barrel plurality of radial projections formed on either the inner peripheral surface Neu deviation of the circular opening, and the other side of the inner circumferential surface of the circular opening of the outer peripheral surface and the lens support cylinder of the cylindrical lens frame And a radial groove through which the plurality of radial protrusions pass, and which communicates with the radial groove, and which is closer to the optical axis than the radial protrusions.
A circumferential engaging hook portion having a large size and capable of engaging with the radial projection, wherein the plurality of radial projections and the radial groove compress the O-ring when their positions are matched. allow relative movement in the direction of the cylindrical lens frame and the lens support cylinder, and the radial projection engaging hook the plurality of rotated relative to the cylindrical lens frame and the lens support cylinder while compressing the O-ring After that, when the compressed state of the O-ring is released,
Relative rotation between the cylindrical lens frame and the lens support cylinder
Is prohibited .

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on illustrated embodiments. In this embodiment, the present invention is applied to the lens shutter type zoom lens camera shown in FIG. 13. First, the concept of the zoom lens camera will be described with reference to FIG. The lens configuration is the front group lens L
1 and a rear lens unit L2.

[0007] The camera body includes an overall movement motor control means 60, a rear group movement motor control means 61, and a zoom operation means 6.
2, shutter release means 63, distance measuring device 64, photometric device 65, and AE motor control means 66 are provided.

When the zoom operating means 62 such as a zoom lever provided on the camera body is operated, the whole moving motor control means 60 controls the whole moving motor 25 by a zoom lens comprising a front lens group L1 and a rear lens group L2. A command for moving the camera from the wide side to the tele side, or a command for moving the camera from the tele side to the wide side. The focal length is changed by the operation of the zoom operation unit 62 by the photographer, and is set to an arbitrary focal length. The image magnification of the finder field is changed in conjunction with the focal length change by the zoom operation means 62. Therefore, the photographer can know the change in the focal length due to the operation of the zoom operation unit 62 by observing the change in the image magnification of the finder field. The focal length set by the operation of the zoom operation unit 62 can be recognized by, for example, a numerical value displayed on an LCD display panel (not shown).

When the shutter release means 63 is operated, the whole-group moving motor control means 60 is driven by the rear-group moving motor control means 61.
At the same time, the overall movement motor 25 is driven to focus the zoom lens on the subject. The shutter release means 63
The shutter button is constituted by a release button. When the shutter button is depressed one step, a distance measurement command to the distance measurement device 64 and a photometry command to the photometry device 65 are given. Then, the shutter 27 of the AF / AE shutter unit 21 is operated. The shutter 27 receives the photometric output from the photometric device 65 and opens its shutter blade 27a for a predetermined time.

When operated, the zoom operation means 62 drives the whole movement motor 25 to move the front lens group L1 and the rear lens group L2 integrally. At the same time as this movement, the rear group moving motor 30 may be operated via the rear group moving motor control means 61. However, the important point of this zoom lens camera is that the front group lens L1 and the rear group lens The movement of L2 is not performed by the conventional zooming concept of continuously changing the focal length without moving the focal point position. That is, when the zoom operation means 62 is operated, only the whole movement motor 25 is operated, and the front group lens L
1 and the rear group lens L2 are moved back and forth without changing the air gap between them, and the front group lens L1 and the rear group lens L2 are operated by operating both the overall movement motor 25 and the rear group movement motor 30. Is moved while changing the air gap between the two.

In the embodiment of the present invention, it is impossible that a subject at a specific distance is always in focus. However, in a lens shutter type camera such as this camera which does not observe an image taken by a photographing optical system, the focus is set at the time of shutter release. There is no problem at all if it fits. In the aspect, the front lens group L1 and the rear lens group L2 are moved while allowing the focal position to move, and both the entire moving motor 25 and the rear group moving motor 30 are operated during the shutter release to focus. .

After executing any one of the above-described control modes in response to the operation of the zoom operation means 62, the shutter release means 63 is operated in at least a part of the focal length range of the focal length set by the zoom operation means 62. When this is done, the whole moving motor 25 and the rear group moving motor 30
Are operated to focus on the subject. The amount of movement of the front group lens L1 and the rear group lens L2 by the entire movement motor 25 and the rear group movement motor 30 at this time is not limited to the amount of movement obtained by subject distance information by the distance measuring device 64,
It is determined in consideration of the amount of movement obtained by the focal length information set by the zoom operation means 62. As described above, when the shutter release means 63 is operated and both the overall movement motor 25 and the rear group movement motor 30 are operated to perform the focusing operation, the degree of freedom in controlling the lens position is increased, and the control thereof is performed. Becomes easier.

Note that, theoretically, when the zoom operating means 62 is operated, the entire moving motor 25 and the rear group moving motor 30 are moved.
Without operating any of them, only the view magnification of the finder and the focal length information are changed, and the shutter release means 63
Is operated, the focal length information and the distance measuring device 64
, The front and rear group lenses L1 and L2 are moved to the positions uniquely determined by the focal length information and the subject distance information. It can also be done.

Next, an embodiment in which the zoom lens barrel having the above concept is concretely described mainly with reference to FIGS. 11 and 12. FIG. First, the schematic configuration and operation of the zoom lens barrel 10 will be described. In order from the front, a first movable barrel 20 (lens support barrel), a second movable barrel 19, a third movable barrel 16, and a fixed mirror A cylinder block 12 is provided. The third movable lens barrel 16 is screwed to the cylindrical part of the fixed lens barrel block 12,
It advances and retreats in the optical axis direction with the rotation. Third movable lens barrel 16
Has a rectilinear guide tube 17 whose rotation is regulated, which moves integrally with the optical axis direction, and the second movable barrel 19 rotates in the optical axis direction while rotating relative to the rectilinear guide tube 17. Retreat. The rotation of the first movable lens barrel 20 is restricted,
Due to the relative rotation with respect to the movable lens barrel 19, it moves forward and backward in the optical axis direction. The whole moving motor 25 is fixed to the fixed lens barrel block 12, and the shutter mount 40 on which the AE motor 29 and the rear group moving motor 30 are mounted is fixed to the first moving lens barrel 20. The front group lens L1 is a lens having a positive power supported by a front lens support cylinder 34 (cylindrical lens frame), and the rear lens L2 is a negative power supported by a lens support cylinder 50. Lens.

The fixed lens barrel block 12 fixed in front of the aperture plate 14 of the camera body has a female helicoid 12a, a plurality of rectilinear guide grooves 12b parallel to the optical axis O, on the inner peripheral surface of the cylindrical portion. have. A code plate 13a having a predetermined pattern is fixed to the bottom of one of the plurality of straight guide grooves 12b. This code plate 13
a is configured as a part of the flexible printed circuit board 13 located outside the fixed lens barrel block 12. The aperture plate 14 has an aperture 14a for determining an exposure area on the film.

The cylindrical portion of the fixed lens barrel block 12 has a gear housing portion 12c bulging radially outward and extending in the optical axis direction.
Are formed (see FIG. 7). This gear storage section 12c
, A driving pinion 15 long in the optical axis direction is rotatably housed. The drive pinion 15 has both ends of the shaft 7 rotatably supported by a support hole 4 provided in the fixed lens barrel block 12 and a support hole 31 a provided in the gear support plate 31. The tooth surface of the drive pinion 15 projects from the inner peripheral surface of the fixed lens barrel block 12.

A third movable barrel 16 is screwed into the inner periphery of the fixed barrel block 12. This third movable lens barrel 16
Has a plurality of linear guide grooves 16 extending in the optical axis direction on the inner peripheral surface.
and a male helicoid 16a that meshes with the female helicoid 12a of the fixed lens barrel block 12 and an outer peripheral gear 16b (see FIG. 6) that meshes with the drive pinion 15 on the outer periphery of the rear end portion. The drive pinion 15 includes a third movable lens barrel 16.
Has an axial length that meshes with the outer peripheral gear 16 in the entire moving range in the optical axis direction.

A linear guide tube 17 is supported on the inner periphery of the third movable lens barrel 16 so as to be integrally movable with the third movable lens barrel 16 in the optical axis direction and relatively rotatable around the optical axis. . The rectilinear guide cylinder 17 includes a rear end flange portion 17d having a plurality of engagement protrusions 17c protruding radially outward on the rear outer periphery,
A retaining flange 1 having a smaller diameter than the flange 17d, which is provided with a slight gap in front of the rear end flange 17d.
7e. A plurality of notches 17f are formed in the circumferential direction of the retaining flange 17e. The third movable lens barrel 16 has a plurality of engaging projections 16d (see FIG. 11) protruding inward in the radial direction on the inner periphery of the rear end, and the engaging projections 16d are inserted from the cutouts 17f. Both flanges 1
It is located in the gap between 7d and 17e, and is connected to the rectilinear guide tube 17 by rotating relative to the rectilinear guide tube 17. An aperture 14a is provided on the rear end face of the
An aperture plate 23 having an opening 23a having substantially the same shape as that of the aperture plate 23 is fixed. The engaging projection 17c is attached to the fixed lens barrel block 12
Is slidably engaged with the straight guide groove 12b parallel to the optical axis O, and its rotation is restricted. 1 of the engagement projection 17c
A contact terminal 9 for slidingly contacting the code plate 13a and generating a signal corresponding to the focal length during zooming is fixed to the engagement projection 17c '.

The straight guide cylinder 17 also has an inner peripheral surface
A plurality of rectilinear guide grooves 17a parallel to the optical axis O and a plurality of lead grooves 17b penetrating the peripheral wall of the guide cylinder 17 and inclined with respect to the circumferential direction and the optical axis direction are formed.

A second movable lens barrel 19 is fitted on the inner circumference of the straight guide cylinder 17. The second movable lens barrel 19 has a plurality of lead grooves 19 that are inclined on the inner peripheral surface in a direction opposite to the lead grooves 17b.
and a plurality of follower projections 19a having a trapezoidal cross section protruding outward in the radial direction and a follower pin 18 located on the follower projection 19a. The follower pin 18 includes a ring member 18a and a center fixing screw 18b that supports the ring member 18a on a follower projection 19a. The follower projection 19a
Slidably fitted in the lead groove 17b of the straight guide cylinder 17,
The follower pin 18 is provided in the straight guide groove 1 of the third movable lens barrel 16.
6c slidably fits. Therefore, when the third movable lens barrel 16 rotates, the second movable lens barrel 19 rotates and moves straight in the optical axis direction.

A first movable lens barrel 20 is fitted on the inner periphery of the second movable lens barrel 19. The first movable lens barrel 20 engages a plurality of follower pins 24 provided on the outer periphery of a rear end portion with a corresponding inner peripheral lead groove 19c, and a linear guide member 22.
Is guided straight ahead. This straight guide member 22 is
As shown in FIGS. 1 and 2, an annular portion 22a, a pair of guide legs 22b extending from the annular portion 22a in the optical axis direction,
The linear guide groove 1 protrudes radially outward of the annular portion 22a.
A guide leg portion 22b is inserted between the inner peripheral surface of the first movable lens barrel 20 and the AF / AE shutter unit 21 so as to be capable of linearly guiding. are doing.

The annular portion 22a of the straight guide member 22
The second movable lens barrel 19 is coupled to the rear end portion so as to be integrally movable in the optical axis direction and relatively rotatable around the optical axis. The rectilinear guide member 22 has a rear end flange portion 22d having a plurality of engagement protrusions 28 protruding radially outward on a rear outer periphery.
And a retaining flange portion 22c smaller in diameter than the flange portion 22d, provided with a slight gap in front of the rear end flange portion 22d, and a plurality of notches 22e in the circumferential direction of the retaining flange portion 22c. (See FIGS. 1 and 2). The second movable lens barrel 19 has a plurality of engaging projections 19b (see FIG. 11; only one is shown in FIG. 11) protruding radially inward on the inner periphery of the rear end portion. The projection 19b is inserted from the notch 22e to form the two flanges 22c, 2c.
It is positioned in the gap between 2d and is connected to the linear guide member 22 by rotating relative to the linear guide member 22. According to the above configuration, when the second movable barrel 19 rotates in the forward and reverse directions, the first movable barrel 20 remains rotated while the rotation is restricted.
It moves straight back and forth with respect to the second movable lens barrel 19 in the optical axis direction.

In the present zoom lens barrel 10, the front lens support cylinder 34 supporting the front lens L1 is provided with a first lens in order to make the zoom lens waterproof, rationalize the shutter unit structure, or realize effective use of space. The rear lens group L2 is fixed to the movable lens barrel 20 by a bayonet method so that the rear lens group L2 is suspended from the main body of the AF / AE shutter unit 21, and a bias is applied between the lens support cylinder 34 and the movable lens barrel 20. An O-ring 81 which is both a means and a waterproof means is interposed. In such a structure, in order to ensure the optical position accuracy of the front group lens L1 with respect to the rear group lens L2, in the present zoom lens barrel 10, only between the front group lens support barrel 34 and the first movable barrel 20. Instead of this front lens support cylinder 34,
A positioning portion is also provided between the shutter mount 40 and the shutter mount 40 on which the shutter 27 having the AE function is mounted. This positioning portion is provided with a center hole 40d formed in the shutter mount 40.
And a fitting portion 3 formed at the rear end of the front lens support cylinder 34.
4a. This positioning portion will be described later in detail.

At the front end of the first movable lens barrel 20, a barrier device 35 having barriers 48a and 48b is mounted.
An AF / AE shutter unit 2 having a shutter 27 including three shutter blades 27a (FIG. 5) on the inner peripheral surface.
1 is fitted and fixed. The AF / AE shutter unit 21 has a plurality of fixing holes 40a (FIG. 3) formed at equal angular intervals on the outer periphery of the shutter mount 40.
The plurality of follower pins 24 also serve as fixing means for the AF / AE shutter unit 21, and are provided in a pin hole 20 a formed in the first movable lens barrel 20 and the fixing hole 40 a.
The follower pin 24 is fitted and fixed, and the shutter unit 21 is fixed to the first movable lens barrel 20 (see FIG. 4). The follower pin 24 can be fixed by, for example, bonding, screwing, or the like. 41 is the first movable lens barrel 20
This is a decorative plate that is fixed to the front end of the display.

The AF / AE shutter unit 21 is shown in FIG.
12, a shutter mount 40, a shutter blade support ring 46 fixed to the rear of the shutter mount 40, and a lens support movably supported with respect to the shutter mount 40. Tube 50 (rear group lens L
2). The front lens L1, the AE motor 29, and the rear group moving motor 30 are supported by the shutter mount 40. The shutter mount 40 has an annular portion provided with a photographing opening 40d through which the front lens support tube 34 is inserted, and three leg portions 40b extending rearward from the annular portion. Two of the gaps between the three leg portions 40b are configured as straight guide portions 40c that guide the movement by slidably engaging the pair of guide legs 22b of the straight guide member 22, respectively.

The shutter mount 40 further includes an AE gear train 45 for transmitting the rotation of the AE motor 29 to the shutter 27.
And the rotation of the rear group moving motor 30 with the screw shaft 4
3 and the photo interrupters 56 and 57 connected to the flexible printed circuit board 6.
Rotating plates 58, 5 having a number of circumferential slits
9 are supported. The photointerrupter 57 and the rotating plate 59 constitute a rear group moving motor encoder for detecting the rotation of the rear group moving motor 30, and the AE motor 29 is formed by the photointerrupter 56 and the rotating plate 58.
An AE motor encoder that detects the rotation of the motor is configured.

Between the shutter mount 40 and the shutter blade support ring 46 fixed to the mount 40, the shutter 2
7, a support member 47 for pivotally supporting the three shutter blades 27a of the shutter 27, and an annular driving member 49 for applying a rotational power to the shutter blades 27a. The annular driving member 49 includes three operation protrusions 49a respectively engaging with the three shutter blades 27a at equal angular intervals. The shutter blade support ring 46 is provided at the front wall with the photographing opening 4.
6a and three support holes 46b provided at equal angular intervals around the photographing opening 46a.
It has a flexure restricting surface 46c that is exposed from 0c and slidably supports the inner peripheral surfaces of the pair of guide legs 22b (see FIGS. 9 and 10).

The supporting member 47 located in front of the shutter blade supporting ring 46 includes a photographing opening 47a facing the photographing opening 46a, and three shaft portions 47b (see FIG. 5) facing the three support holes 46b. (Only parts are shown). Each of the three shutter blades 27a has, at one end, a shaft hole 27b through which the shaft 47b is inserted, and at the other end, a shielding portion that shields the imaging openings 46a, 47a.
An elongated hole 27c is provided between the one end and the other end to allow the operation projection 49a to pass therethrough. The support member 47 includes a shaft portion 47b supporting the shutter blade 27a.
The shutter blade support ring 46 is fixed to the shutter blade support ring 46 in a state of being fitted into the corresponding support hole 46b.

The annular driving member 49 has a gear train 4 on its outer periphery.
5 has a gear portion 49b for receiving rotation from. The support member 47 has three arc grooves 47c in the circumferential direction at positions close to the three shaft portions 47b. The three operation projections 49a of the annular driving member 49 penetrate through the three arc grooves 47c, and the long holes 27 of the respective shutter blades 27a.
c. The shutter blade support ring 46 is inserted from the rear side of the shutter mount 40 while supporting the annular driving member 49, the support member 47, and the shutter 27, and is screwed to the shutter mount 40.

Behind the shutter blade support ring 46, there is disposed a lens support tube 50 supported on the shutter mount 40 via slide shafts 51 and 52 so as to be relatively movable. The shutter mount 40 and the lens support cylinder 50 are urged to move in the direction away from each other by the coil spring 3 fitted to the slide shaft 51, thereby eliminating play between them. The drive gear 42a provided in the gear train 42 is restricted from moving in the axial direction, and a female screw is formed on the inner periphery thereof. A screw shaft 43 having one end fixed to the lens support cylinder 50 is screwed to the female screw.
And the screw shaft 43 constitute a feed screw mechanism. Therefore, when the rear group moving motor 30 is driven to rotate and the drive gear 42a rotates forward or backward, the screw shaft 43 advances and retreats with respect to the drive gear 42a, and is supported by the lens support tube 50, that is, the support tube 50. The rear lens group L2 moves relative to the front lens group L1.

At the front of the shutter mount 40, holding members 53, 55 for holding the motors 29, 30 and the like supported by the shutter mount 40 are screwed. The motors 29 and 30 and the photo interrupters 56 and 57 are connected to the flexible printed circuit board 6 having one end fixed to the shutter mount 40. In a state where the first to third movable lens barrels 20, 19, 16 and the AF / AE shutter unit 21 and the like are assembled, an aperture plate 23 is fixed to the rear end face of the straight guide cylinder 17, and the front end of the fixed lens barrel block 12. An annular retaining member 33 is fitted to the portion.

In the present embodiment, the front lens group L1 and the rear lens group L2 are respectively connected to the AF / AE shutter unit 21.
The AE motor 29 and the rear group moving motor 30 are mounted on the unit 21. According to this configuration, there is an advantage that the supporting structure and the driving structure of the front lens unit L1 and the rear lens unit L2 can be simplified, but at least one of the front lens unit L1 and the rear lens unit L2 is
Shutter mount 40, annular drive member 49, support member 4
7, the zoom lens is realized even if the AF / AE shutter unit 21 including the shutter 27 and the shutter blade holding ring 46 is provided as a separate member and is supported by a support member different from the unit.

Hereinafter, a supporting device for a front lens unit to which the present invention is applied will be described with reference to FIG. 11 and FIGS. The first movable lens barrel (lens support cylinder) 20
An inner flange 20b (see FIGS. 11 and 1) having a center hole 20 formed integrally with the lens barrel 20 and fitted with a front end portion of a front lens support tube (front lens tube) 34 at the front inner peripheral side.
4). The center hole 20 e regulates the radial movement of the front end portion of the fitted front lens group support tube 34 to determine the position of the front lens group L <b> 1 with respect to the first movable lens barrel 20 mainly in the radial direction. Three engaging claws 20c (radial projections) are formed at equal angular intervals (see FIGS. 14, 18, and 19) on the inner peripheral edge of the inner flange 20b. After the engagement claw 20c is inserted from the notch 34f (radial groove) of the front lens support cylinder 34 toward the circumferential groove 34g, the support cylinder 34 and the first movable lens barrel 20 are relatively rotated. To engage with the engagement hook 34h . Inner flange 20
In front of the center hole 20e at the inner peripheral edge portion b, an annular portion 20d (a front peripheral edge of the lens supporting cylinder) that sandwiches the O-ring 81 with the outer flange 34j (outer flange) of the front lens supporting cylinder 34. ) Is formed.

A follower pin 2 is provided on the inner surface of the first movable lens barrel 20.
AF / AE shutter unit 2 fixed via
The shutter mounting base (shutter mounting cylinder) 40, which is one of the members constituting the first component 1, is attached to the annular portion (inner flange) 40f.
Center hole 4 for fitting the rear end portion of front lens support cylinder 34
0d. The center hole 40d is formed at the rear end of the front lens support tube 34 and regulates the radial movement of the fitting portion 34a fitted in the center hole 40d. The optical position mainly in the radial direction of the front lens group L1 with respect to the rear lens group L2 supported together by 40 is determined.

As shown in FIG. 15, the front lens support cylinder 3
4 is a central hole 20 of the first movable lens barrel 20 near its front end.
e, which has an annular fitting portion 34e slightly smaller in diameter than the center hole 20e. The front lens support cylinder 34 also has, at its rear end, an annular fitting portion 34a having a diameter slightly smaller than the center hole 40d, which fits into the center hole 40d of the shutter mount 40. 34e and fitting part 34
The insertion portion 34c has a smaller diameter than the fitting portion 34e and is inserted into the AE motor 29 or the like on the inner side. An inner flange 34b (see FIG. 11) is formed at the rear end of the front group lens support cylinder 34 to abut the rear surface of the front group lens L1 fitted inward. The fitting portion 34a has a center hole 40d located on the inner peripheral side of the inner surface 29a of the AE motor 29.
Is smaller than the insertion portion 34c. The front lens support cylinder 34 has, in front of the fitting portion 34e, a circumferential groove portion 34g in which the O-ring 81 is fitted, and an outer flange 34j having a larger diameter than the fitting portion 34e. The fitting portion 34e has three notches 34f through which the three engaging claws 20c pass, and three engaging hooks 34h adjacent to the notches 34, respectively. The three engagement claws 20c, the three notches 34f, and the three engagement hooks 34h are provided at equal angular intervals. The notch 34f and the engaging hook 34h adjacent to each other
As shown in FIG. 15, they communicate in the circumferential direction. The O-ring 81 moves and urges the outer flange 34j in a direction away from the inner flange 20b to maintain the engagement state between the engagement hook 34h and the engagement claw 20c, and to cause the first movable lens barrel to move. Watertightness is maintained between the lens barrel 20 and the front lens support cylinder 34 to make them waterproof.

The front lens support cylinder 34 also includes a fitting portion 34.
e, a female screw portion 34i is provided on the inner peripheral side of the outer flange 34j and the like. The female screw portion 34i is screwed with a male screw portion 80a of a lens holding ring 80 for fixing the front lens L1 fitted to the front lens support tube 34 to the support tube 34. The lens holding ring 80 is a front lens L1.
Annular contact surface 80b abutting on the peripheral edge of the front face of
have. A waterproof coating material is applied to the annular contact surface 80b, and the waterproof performance between the front lens support cylinder 34 and the front lens L1 is enhanced.

The zoom lens barrel 10 having the front-group lens support device having such a configuration can perform the assembling work of the front-group lens L1 and the like as follows. First, the shutter mounting base 40 on which the annular driving member 49, the support member 47, the shutter 27, the shutter blade holding ring 46 and the like are mounted,
The rear group lens L2 is supported so as to have a predetermined positional relationship with the center hole 40d, and the AF / AE shutter unit 21 is assembled. Then, the AF / AE shutter unit 21 is inserted into the inside of the first movable lens barrel 20, and the follower pin 24 inserted through the pin hole 20a is fitted and fixed in a fixing hole 40a provided in the shutter mounting base 40, The shutter mount 40 is fixed to the first movable barrel 20 so as to have a predetermined relationship with the movable barrel 20. Follower pin 24
Can be fixed by, for example, bonding, screwing, or the like.

Thereafter, the front lens L1 is fitted inside the front lens support cylinder 34, and the lens press ring 80 is screwed into the female screw portion 34i to fix the lens L1. The O-ring 81 is fitted into the circumferential groove 34g of the support cylinder 34. The front lens support cylinder 34 in this state is inserted through the center hole 20e from the rear side, and the smallest diameter fitting portion 3 is formed.
4a is moved toward the center hole 40d. Then, when the rear end fitting portion 34a enters the center hole 40d, each notch 34f engages with the corresponding engaging claw 20c, and the front fitting portion 34e fits into the center hole 20e.

In this state, the front lens support cylinder 34
Are formed at the front end thereof at substantially equal intervals by a plurality of engagement recesses 3.
4k is rotated clockwise in FIG. 15 while pinching it with a predetermined jig (not shown) or the like and pushing it toward the inner flange 20b. When the front group lens support cylinder 34 is released when the three engagement hooks 34h of the front group lens support cylinder 34 have respectively engaged with the three engagement claws 20c, the O-ring 81 elastically contacting the annular part 20d is formed. The lens support cylinder 34 is pushed back forward of the optical axis. Therefore, in a state where the fitting portion 34e is fitted in the center hole 20e, the engaging hook 34h is strongly engaged with the engaging claw 20c. In other words, as shown in FIG. 17, the area of the engaging hook portion 34h is formed to be larger than the cross-sectional area of the hatched portion of the engaging claw 20c so as to allow a margin in the thrust direction (the left-right direction in FIG. 17). I have. Then, the engagement hook 34h and the engagement claw 20 are utilized by utilizing the elastic force of the O-ring 81.
c. For this reason, there is a feature that the axial position (optical axis direction position) of the front lens group support tube 34 with respect to the first movable lens barrel 20 is more easily determined than the conventional method in which a member is pressed into a groove, for example.

Further, the engaging hooks 34h arrange the engaging claws 20c at equal angular intervals (see FIGS. 18 and 19), and can be attached at any angular position. It is formed with such accuracy that it can receive the elastic force evenly. Therefore, it is not necessary to select a specific combination of the engagement hook 34h and the engagement claw 20c during assembly. Thereby, the front group lens support cylinder 3
4 is accurately positioned in a predetermined relationship with respect to the first movable lens barrel 20 and the shutter mount 40, and the position of the front lens group L1 with respect to the rear lens group L2 supported by the shutter mount 40, particularly in the radial direction, is easy. , The optical axes of the front lens group L1 and the rear lens group L2 are matched. As described above, according to the front lens group support device, the optical axes of the front lens group L1 and the rear lens group L2 can be easily matched, and the optical position accuracy of both can be ensured. Further, as mentioned above,
It is not necessary to select a specific combination of the engagement hook portion 34h and the engagement claw 20c at the time of assembling. Therefore, if the lens frame or the lens barrel is loose or has an inclination (fall) due to an assembling error, the assembling is not performed. Engagement hook 34h and engagement claw 2
By changing the combination of the first movable barrel 2
It is possible to slightly change (adjust) the assembling position of the front lens support cylinder 34 with respect to 0. In other words, by changing the assembling position, it is possible to adjust the tilt of the lens frame or the lens barrel to some extent. In addition, if the above-mentioned fall cannot be sufficiently canceled only by changing the mounting position of the front-group lens support cylinder 34 with respect to the first movable lens barrel 20, a lens frame or a lens barrel having a play or an assembly error is further removed. By appropriately adjusting (changing the mounting angle position of the lens frame or the lens barrel), the tilt can be totally canceled.

The zoom lens camera operates as follows. When the power switch (not shown) is turned on while the zoom lens barrel 10 is in the lens retracted state shown in FIG. Then, this rotation is transmitted to the drive pinion 15 via the gear train 26 supported by the support portion 32, and the third
Since the movable lens barrel 16 is rotated in the extending direction, the second movable lens barrel 19 and the first movable lens barrel 20 are slightly extended in the optical axis direction together with the third movable lens barrel 16, and the camera widens the zoom lens. The camera is ready for shooting at the end.

In this photographing enabled state, when the zoom operation means 62 is operated to the telephoto side, the whole movement motor 25 is driven to rotate in the forward direction via the whole movement motor control means 60, and is driven via the drive pinion 15 and the outer peripheral gear 16b. To rotate the third movable barrel 16 in the extending direction. Therefore,
The third movable lens barrel 16 is extended from the fixed lens barrel block 12 due to the relationship between the female helicoid 12a and the male helicoid 16a, and at the same time, the straight guide tube 17 is fixed by the relationship between the engagement projection 17c and the straight guide groove 12b. Block 12
With the third movable lens barrel 16 in a state of not rotating relative to the optical axis, it advances forward of the optical axis. At this time, the second movable lens barrel 19
The follower pin 18 is connected to the lead groove 17b and the linear guide groove 1
By simultaneously engaging with the third movable lens barrel 6c, the second movable lens barrel 6 relatively moves in the same direction as the third movable lens barrel 16 and moves forward in the optical axis with respect to the third movable lens barrel 16. The first movable lens barrel 20 is
Since the linear movement guide member 22 guides the linear movement and the follower pin 24 is moved and guided by the lead groove 19 c, the second movable lens barrel 19 and the AF / AE shutter unit 21 are not rotated relative to the fixed lens barrel block 12. Advances ahead of the optical axis.

While the zoom lens barrel 10 is driven in this manner, the rear group moving motor 30 is not driven, so that the front lens group L1 and the rear lens group L2 are integrated with the optical axis while maintaining a constant distance from each other. (See FIG. 8). The focal length set by the zoom operation unit 62 is displayed by a display unit (not shown).

When the release button is depressed one step at an arbitrary focal length set by the zoom operation means 31, a distance measuring command is given to the distance measuring device 64 and a light measuring command is given to the light measuring device 65, so that the distance measuring operation is performed. Photometry is started. Thereafter, when the release button is depressed two steps, both the whole moving motor 25 and the rear group moving motor 30 move the moving amount obtained by the distance measuring device 64 based on the subject distance information and the focus set by the zoom operating means 31. The AE motor control means 6 moves the front lens group L1 and the rear lens group L2 by a movement amount determined in consideration of the movement amount obtained from the distance information to set the focal length and focus on the subject.
The AE motor 29 rotationally drives the annular driving member 49 in accordance with the subject luminance information from the photometric device 65 via 6 to drive the shutter 27 so as to satisfy a predetermined exposure. After the end of the shutter release, both the overall movement motor 25 and the rear group movement motor 30 are immediately driven, and the front lens group L1 and the rear lens group L2 are returned to the state before the shutter release.

When the zoom operation means 62 is operated to the wide side, the whole moving motor 25 is driven to rotate in the reverse direction, and the third movement is performed.
The movable lens barrel 16 is rotated in the retracting direction, and is retracted into the fixed lens barrel block 12 together with the rectilinear guide cylinder 17. At the same time, the second movable lens barrel 19 is retracted into the movable lens barrel 16 while rotating in the same direction as the third movable lens barrel 16, and
The movable lens barrel 20 is moved by A with respect to the rotating second movable lens barrel 19.
It is moved together with the F / AE shutter unit 21.
Also during this retraction drive, the rear group moving motor 30 is not driven, as in the above-described retraction drive. When the power switch is turned off after the zoom lens has moved to the wide end position, the zoom lens barrel 10 is moved into the lens storage position shown in FIG.

[0046]

As described above, according to the lens supporting structure of the present invention, in the structure in which the cylindrical lens frame on which the lens is fixed is supported by the lens supporting cylinder, the uniformity of the O-ring caused by the O-ring in front of the optical axis. Due to the resilient force, the axial position of the cylindrical lens frame with respect to the lens support cylinder can be accurately determined.Furthermore, the assembling position of the cylindrical lens frame with respect to the lens support cylinder during assembly is adjusted, Can counteract a certain amount of fall.

Further, according to the third aspect of the invention, in addition to the effect of the first aspect, watertightness between the lens support cylinder and the cylindrical lens frame can be maintained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of an embodiment of a straight guide mechanism to which the present invention is applied.

FIG. 2 is a perspective view showing a state different from FIG. 1 of a main part of the rectilinear guide mechanism.

FIG. 3 is a perspective view showing a main part of a zoom lens barrel according to the embodiment.

FIG. 4 is a perspective view showing a state in which an AF / AE shutter unit of the zoom lens barrel is assembled to a first movable barrel.

FIG. 5 is an exploded perspective view showing main members of an AF / AE shutter unit of the zoom lens barrel.

FIG. 6 is a perspective external view showing a third movable lens barrel of the zoom lens barrel.

FIG. 7 is a front view showing a fixed barrel block of the zoom lens barrel.

FIG. 8 is an upper half sectional view showing a maximum extension state of the zoom lens barrel.

FIG. 9 is an upper half sectional view showing a main part of the zoom lens barrel in a lens housed state.

FIG. 10 is an upper half sectional view showing a main part of the zoom lens barrel in a maximum extended state.

FIG. 11 is an upper half cross-sectional view showing a lens storage state of the entire zoom lens barrel.

FIG. 12 is an exploded perspective view showing the entire zoom lens barrel.

FIG. 13 is a block diagram showing a control system for controlling the operation of the zoom lens barrel.

FIG. 14 is a perspective view of a front group support frame and a lens support cylinder to which the present invention is applied.

FIG. 15 is an enlarged perspective view showing a front lens support cylinder of the zoom lens barrel.

FIG. 16 is an enlarged sectional view of a front group support frame and a lens support cylinder to which the present invention is applied.

17 is an enlarged plan view of an engagement portion between the front group support frame and the lens support cylinder shown in FIG.

FIG. 18 is an enlarged front view of a lens support cylinder.

FIG. 19 is an enlarged development view of the front group support frame.

[Explanation of symbols]

Reference Signs List 20 First movable lens barrel (lens support cylinder) 20b Inner flange 20c Engagement claw (radial projection) 20d Annular part (front edge of lens support cylinder) 34 Front group lens support cylinder 34e Fitting part 34f Notch (radial direction) Groove) 34g Circular groove 34h Engagement hook 34j Outer flange (outer flange) 81 O-ring

Continuation of the front page (56) References JP-A-7-114079 (JP, A) JP-A-6-27520 (JP, A) Japanese Utility Model Application No. Sho 62-170918 (JP, U) Japanese Utility Model Application Utility Model No. Sho 55-149709 (JP, A) , U) (58) Fields surveyed (Int. Cl. ⁷ , DB name) G02B ⁷ /02-7/105 G03B 17/08

Claims (3)

(57) [Claims] A cylindrical lens frame to which a lens is fixed; a lens support cylinder having a circular opening into which the cylindrical lens frame is inserted; and a cylindrical lens frame opposed to a front edge of the circular opening of the lens support cylinder. An outer flange formed; an O-ring sandwiched between an outer flange of the cylindrical lens frame and a peripheral edge of the front surface of the lens support tube; an outer peripheral surface of the cylindrical lens frame and a circular opening of the lens support tube; a plurality of radial projections formed on either circumferential surface Neu deviation;
And formed on the other side of the inner circumferential surface of the circular opening of the outer peripheral surface of the cylindrical lens frame and the lens support tube, and radial grooves for passing the plurality of radial protrusions, when communicating with the radial grooves
In both cases, the dimension in the optical axis direction is larger than the radial projection.
And a circumferential engaging hook engageable with the radial projection.
Part; includes a plurality of radial projections and radial grooves allow the relative movement direction of the cylindrical lens frame and a lens support cylinder for compressing the O-ring when is matched its position, and the plurality of The radial projection and the engaging hook portion rotate the cylindrical lens frame and the lens support cylinder in a state where the O-ring is compressed, and then rotate the O-ring.
The cylindrical lenses engage with each other when the compressed
A lens support structure wherein relative rotation between the zoom frame and the lens support cylinder is prohibited . 2. The lens support structure according to claim 1,
The plurality of radial grooves, radial protrusions andEngaging hook
Is a lens support structure provided at equal angular intervals. 3. The lens supporting structure according to claim 1, wherein the outer flange of the cylindrical lens frame in which the O-ring is sandwiched and the front peripheral edge of the lens supporting cylinder are formed in a cylindrical shape by the O-ring. A lens support structure configured to maintain watertightness between lens frames.