JPH09203846A - Straight-moving guide mechanism of lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a straight-moving guide mechanism which makes a zoom lens barrel more small-sized while the number of components is decreased. SOLUTION: This lens barrel 10 is equipped with an AF/AE shutter unit 21, a 1st moving lens barrel 20 which moves along the optical axis while the shutter unit 21 is fixed, and a straight-moving guide member 22 which guides the 1st moving lens barrel 20 to move only straight while restricting the rotation of the 1st moving lens barrel 20. At this time, part of a member which constitutes the AF/AE shutter unit 21 is provided with a deflecting restriction surface 46c which engages the straight-moving guide member 22 from radially inside.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens mirror provided with a rectilinear barrel that fixes a shutter unit and moves in the optical axis direction, and a rectilinear guide member that restricts the rotation of the rectilinear barrel and guides only the rectilinear movement. The present invention relates to a linear guide mechanism for a cylinder.

[0002]

2. Description of the Related Art Conventionally, as a lens shutter type camera, when a zoom lens barrel mounted on a camera body is moved back and forth in the optical axis direction, a shutter unit built into the lens barrel and the shutter unit are supported by the shutter unit. There is known one provided with a linear guide mechanism for restricting the photographing lens so as not to rotate around the optical axis. In such a rectilinear guide mechanism, a rectilinear cylinder that supports the shutter unit and moves in the optical axis direction, and the rotation of the rectilinear cylinder is restricted.
Some have a linear guide member that guides only linear movement. The linear guide member has an annular portion and a guide leg portion extending in the optical axis direction from the annular portion, and the guide leg portion is slidably engaged with the linear guide portion on the shutter unit side, This shutter unit is guided straight ahead.

Since such a linear guide member is usually made of a synthetic resin material, the guide legs made of the same synthetic resin are bent inward in the radial direction of the annular portion by a force applied during zooming. However, if the bending is significant, the guide leg may fall off the straight guide portion. For this reason, it is necessary to provide a portion on the shutter unit side for restricting the bending of the guide leg portion to prevent the guide leg portion from falling off from the straight-ahead guide portion. Since it is provided on another member for supporting the straight-moving barrel, the number of parts increases and it becomes difficult to further reduce the size of the zoom lens barrel.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a rectilinear guide mechanism capable of further downsizing the zoom lens barrel by reducing the number of parts based on the awareness of the problems in the conventional rectilinear guide mechanism. Has an aim.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a shutter unit; a straight advancing cylinder that fixes the shutter unit and moves in the direction of the optical axis; In a lens barrel having a rectilinear guide member for guiding to a guide, a part of a member forming the shutter unit is provided with a drop-out preventing surface that engages with the rectilinear guide member from the inside in the radial direction. I am trying.

A shutter unit is provided with an outer frame annular member made of synthetic resin; located inside the outer frame annular member,
A plurality of fixed bases each having a shutter blade support ring for rotatably supporting the shutter blades, the outer frame annular member being in contact with the inner surface of the straight advancing cylinder and being fixed to the linear advancing cylinder; And a notch for receiving the linear guide member; and a linear guide surface on one side of the notch that engages with the linear guide member in a direction parallel to the optical axis. It can be configured to have a drop-out prevention surface that faces the notch of the outer frame annular member and guides the rectilinear guide member in the radial direction slidably from the inner surface.

[0007]

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 zoom lens camera shown in FIG. 13. First, the concept of this zoom lens camera will be described with reference to FIG. The lens configuration is the front lens group L
1 group and the rear lens group L2.

On the camera body, the overall movement motor control means 60, the rear group movement motor control means 61, and the zoom operation means 6 are provided.
2, a shutter release means 63, a distance measuring device 64, a photometric device 65, and an 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 total movement motor control means 60 controls the total movement motor 25 to include a zoom lens including a front lens group L1 and a rear lens group L2. A movement command for moving the camera from the wide side to the tele side or a movement command for moving the tele side to the wide side is given. The focal length is changed and set to an arbitrary focal length by the operation of the zoom operating means 62 by the photographer. The image magnification of the viewfinder field is changed in association with the change of the focal length 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 means 62 by observing the change in the image magnification of the viewfinder field. The focal length set by the operation of the zoom operation means 62 can be recognized by a numerical value displayed on the LCD display panel (not shown), for example.

The overall movement motor control means 60 is also driven by the rear group movement motor control means 61 when the shutter release means 63 is operated.
At the same time, the whole movement motor 25 is driven to focus the zoom lens on the subject. The shutter release means 63 is
It is composed of a release button, and when it is pressed one step, a distance measuring command to the distance measuring device 64 and a photometric command to the photometric device 65 are given, and when it is pressed twice, the AE motor control means 66 is used.
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 operating means 62 drives the whole moving motor 25 to move the front lens group L1 and the rear lens group L2 integrally. The rear lens group moving motor 30 may be operated via the rear lens group moving motor control means 61 at the same time as this movement, but an important point in this zoom lens camera is that the front lens group L1 and the rear lens group lens by the zoom operation means 62 are operated. It means that the movement of L2 is not performed in the conventional zooming concept in which the focal length is continuously changed without moving the focal position. That is, when the zoom operation means 62 is operated, only the whole movement motor 25 is operated to move the front lens group L.
1 and the rear lens group L2 are moved back and forth without changing the air gap between them, and both the overall movement motor 25 and the rear lens group movement motor 30 are operated to operate the front lens group L1 and the rear lens group L2. It is possible to move while changing the air gap between the two.

In the aspect, the subject at a specific distance cannot always be in focus, but in the lens shutter type camera such as the present camera which does not observe the image by the photographing optical system, it is focused at the time of shutter release. There is no problem at all as it fits. Further, in the mode, while allowing the movement of the focal position, the front lens group L1 and the rear lens group L2 are moved, and both the overall movement motor 25 and the rear group movement motor 30 are operated at the time of shutter release to focus. .

After executing any one of the above control modes in accordance with the operation of the zoom operation means 62, the shutter release means 63 is operated in the focal length range of at least a part of the focal length set by the zoom operation means 62. Then, the whole moving motor 25 and the rear group moving motor 30
Both are operated to focus on the subject. The amount of movement of the front lens group L1 and the rear lens group L2 by the overall movement motor 25 and the rear group movement motor 30 at this time is not limited to the movement amount obtained from the subject distance information by the distance measuring device 64, and
It is determined in consideration of the movement amount obtained by the focal length information set by the zoom operation means 62. As described above, when the shutter release means 63 is operated, if the whole 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 is performed. Will be easier.

Theoretically, when the zoom operating means 62 is operated, the whole moving motor 25 and the rear group moving motor 30 are operated.
The shutter release means 63 is operated by changing only the view field magnification and the focal length information of the finder without operating any of the above.
When the is operated, its focal length information and distance measuring device 64
The overall movement motor 25 and the rear group movement motor 30 are simultaneously operated according to the subject distance information according to, and the front group lens L1 and the rear group lens L2 are moved to positions uniquely determined by the focal length information and the subject distance information. You can also let it.

Next, an embodiment in which the zoom lens barrel of the above concept is embodied will be described mainly with reference to FIGS. 11 and 12. The schematic configuration and operation of the zoom lens barrel (lens barrel) 10 will be described first. First, a first movable barrel 20, a second movable barrel 19, a third movable barrel 16, and a fixed mirror in order from the front. A cylinder block 12 is provided. The third movable lens barrel 16 is screwed into the tubular portion of the fixed lens barrel block 12, and advances and retreats in the optical axis direction with rotation. The third movable lens barrel 16 is
It has a linear guide cylinder 17 whose rotation is restricted, which moves integrally in the optical axis direction, inside, and the second movable lens barrel 19 advances and retreats in the optical axis direction while rotating relative to the linear guide cylinder 17. .
The rotation of the first movable lens barrel 20 is restricted, and the first movable lens barrel 20 moves forward and backward in the optical axis direction by the relative rotation with respect to the second movable lens barrel 19.
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 and is supported by the lens support tube 34, and the rear group lens L2 is
It is a lens having a negative power and supported by the lens support barrel 50.

The fixed lens barrel block 12 fixed to the front of the aperture plate 14 of the camera body has a female helicoid 12a and a plurality of linear guide grooves 12b parallel to the optical axis O on the inner peripheral surface of its 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 board 13
“A” is configured as a part of the flexible printed circuit board 13 located outside the fixed barrel block 12. The aperture plate 14 has an aperture 14a that determines the exposure area on the film.

A gear accommodating portion 12c, which bulges outward in the radial direction and extends in the optical axis direction, is provided in the tubular portion of the fixed lens barrel block 12.
Are formed (see FIG. 7). This gear storage 12c
The drive pinion 15 which is long in the optical axis direction is rotatably accommodated in the. Both ends of the shaft 7 of the drive pinion 15 are rotatably supported by the support hole 4 provided in the fixed lens barrel block 12 and the support hole 31a provided in the gear support plate 31, respectively. The tooth surface of the drive pinion 15 projects to the inner peripheral surface of the fixed barrel block 12.

A third movable lens barrel 16 is screwed onto the inner circumference of the fixed lens barrel block 12. This third movable lens barrel 16
Is a plurality of straight guide grooves 16 extending in the optical axis direction on the inner peripheral surface.
c, and has a male helicoid 16a that meshes with the female helicoid 12a of the fixed 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 a length in the axial direction that meshes with the outer peripheral gear 16 in the entire movement range in the optical axis direction.

A linear guide cylinder 17 is supported on the inner circumference of the third movable lens barrel 16 so as to be movable integrally with the third movable lens barrel 16 in the optical axis direction and relatively rotatable around the optical axis. . The linear guide cylinder 17 has a rear end flange portion 17d provided on the outer periphery of the rear portion with a plurality of engagement protrusions 17c protruding outward in the radial direction,
A retaining flange portion 1 having a smaller diameter than the flange portion 17d, which is provided in front of the rear end flange portion 17d with a slight gap.
7e and. A plurality of cutout portions 17f are formed in the circumferential direction of the retaining flange portion 17e. The third movable lens barrel 16 has a plurality of engagement projections 16d (FIG. 11) protruding inward in the radial direction on the inner circumference of the rear end portion.
Insert d from the above-mentioned notch 17f to insert both flanges 17
It is located in the gap between d and 17e, and is connected to the linear guide tube 17 by rotating relative to the linear guide tube 17. An aperture plate 23 having an opening 23a having substantially the same shape as the aperture 14a is fixed to the rear end surface of the linear guide cylinder 17. The engaging protrusion 17c is slidably engaged with the straight guide groove 12b parallel to the optical axis O of the fixed lens barrel block 12, and its rotation is restricted. 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 engaging projection 17c ', which is one of the engaging projections 17c.

The straight guide cylinder 17 also has an inner peripheral surface,
A plurality of straight 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 linear guide barrel 17. The second movable lens barrel 19 has a plurality of lead grooves 19 on the inner peripheral surface thereof, the lead grooves 19 having a reverse inclination to the lead grooves 17b.
c has a plurality of follower protrusions 19a having a trapezoidal cross-section, and a follower pin 18 located on the follower protrusions 19a. The follower pin 18 includes a ring member 18b and a center fixing screw 18a that supports the ring member 18b on the follower protrusion 19a. The follower protrusion 19a is
Slidably fitted in the lead groove 17b of the straight guide cylinder 17,
The follower pin 18 is the linear guide groove 1 of the third movable lens barrel 16.
6c is slidably fitted. Therefore, when the third movable lens barrel 16 rotates, the second movable lens barrel 19 rotates and moves straight in the optical axis direction.

The first movable lens barrel 20 is fitted on the inner circumference 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 the rear end portion with the corresponding inner peripheral lead grooves 19c, and the linear guide member 22.
Directed by. This linear guide member 22 is
As shown in FIGS. 1 and 2, an annular portion 22a, a pair of guide leg portions 22b extending from the annular portion 22a in the optical axis direction,
The straight guide groove 1 which is projected outward in the radial direction of the annular portion 22a.
7a, and a plurality of engaging projections 28 that slidably engage with each other, and a linear guide portion 40c of the AF / AE shutter unit 21 on the inner peripheral surface of the first movable lens barrel 20 and a guide leg portion 22b.
Is inserted so that it can guide straight ahead.

The annular portion 22a of the linear guide member 22 is
The second movable lens barrel 19 is coupled to the rear end of the second movable lens barrel 19 so as to be movable in the optical axis direction and rotatable relative to the optical axis. The rectilinear guide member 22 has a rear end flange portion 22d provided with a plurality of engaging projections 28 protruding outward in the radial direction on the outer periphery of the rear portion.
And a retaining flange portion 22c having a diameter smaller than that of the flange portion 22d, which is provided in front of the rear end flange portion 22d, and has a plurality of cutout portions 22e in the circumferential direction of the retaining flange portion 22c. Have (see FIG. 1). The second movable lens barrel 19 has a plurality of engagement projections 19b (FIG. 11) protruding inward in the radial direction on the inner circumference of the rear end portion, and the engagement projections 19b are inserted from the cutout portions 22e to both sides. The linear guide member 22 is located in the gap between the flange portions 22c and 22d.
It is connected to the linear guide member 22 by rotating relative thereto. With the above configuration, when the second movable lens barrel 19 rotates in the forward and reverse directions, the first movable lens barrel 20 moves straight forward and backward with respect to the second movable lens barrel 19 while the rotation is restricted. To do.

A barrier device 35 having barriers 48a and 48b is attached to the front end portion of the first movable lens barrel (straightening barrel) 20, and three shutter blades 27a (FIG. 5) are provided on the inner peripheral surface thereof. An AF / AE shutter unit (shutter unit) 21 having a shutter 27 composed of 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 the pin holes 20a formed in the first movable lens barrel 20 and the follower pins 24 are provided in the fixing holes 40a.
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.
Reference numeral 41 is a decorative plate fixed to the front end of the first movable lens barrel 20.

The AF / AE shutter unit 21 is shown in FIG.
12, the shutter mount (outer frame annular member) 40, the shutter blade support ring 46 fixed to the rear part of the shutter mount 40, and the shutter mount 4
Lens support barrel 50 supported so as to be movable relative to zero
(Rear group lens L2). The front lens L1, the AE motor 29, and the rear group moving motor 30 are supported by the shutter mount 40. This shutter mount 4
Reference numeral 0 has an annular portion having a photographing opening 40d through which the lens support cylinder 34 is inserted, and three leg portions (fixing bases) 40b extending rearward from the annular portion. This 3
Two of the gaps between the two leg portions 40b are formed as straight guide portions (notches) 40c for receiving and guiding the pair of guide leg portions 22b of the straight guide member 22 respectively. Both side portions of the straight-movement guide portion 40c are in sliding contact (engagement) with the guide legs 22b of the straight-movement guide member 22.
The straight guide surface 40e is parallel to the optical axis O.

The shutter mount 40 further has an AE gear train 45 that transmits the rotation of the AE motor 29 to the shutter 27.
And the rotation of the rear group movement motor 30 to the screw shaft 4
3 and the photo interrupters 56 and 57 connected to the flexible printed circuit board 6.
And the rotary plates 59, 6 having a large number of slits in the circumferential direction.
0 is supported. The photo interrupter 56 and the rotary plate 59 constitute an encoder for the rear group moving motor that detects the rotation of the rear group moving motor 30, and the photo interrupter 57 and the rotary plate 60 form the AE motor 29.
The encoder for the AE motor that detects the rotation of the is configured.

The shutter 2 is provided between the shutter mount 40 and the shutter blade support ring 46 fixed to the mount 40.
7, a support member 47 that pivotally supports the three shutter blades 27a of the shutter 27, and an annular drive member 49 that applies rotational force to the shutter blades 27a. The annular drive member 49 is provided with three operation protrusions 49a that engage with the three shutter blades 27a at equal angular intervals.

The support member 47 located in front of the shutter blade support ring 46 faces the photographing opening 47a facing the photographing opening 46a and the three support holes 46b formed in the front wall of the supporting ring 46, respectively. It has three shaft portions 47b (only one place is shown in FIG. 5). 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, the photographing openings 46a and 4a.
It has a shielding portion that shields 7a, and has a long hole 27c between the one end portion and the other end portion, through which the operation protrusion 49a is inserted. The support member 47 includes the shaft portions 47b that respectively support the shutter blades 27a and the shutter blade support ring 4
6 is fixed to the shutter blade support ring 46 in a state of being fitted into the corresponding support holes 46b.

The annular drive member 49 has a gear train 4 on its outer peripheral portion.
It has a gear portion 49b that receives rotation from 5. Further, the support member 47 has three circular arc grooves 47c along the circumferential direction at positions close to the three shaft portions 47b. The three operation protrusions 49a of the annular drive member 49 penetrate the three arcuate grooves 47c to form the elongated holes 27 of each shutter blade 27a.
c is engaged. 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.

At the rear of the shutter blade support ring 46, a lens support cylinder 50 supported by the shutter mount 40 via slide shafts 51 and 52 so as to be relatively movable is arranged. The shutter mount 40 and the lens support cylinder 50 are urged to move away from each other by a coil spring 61 fitted to the slide shaft 51, thereby eliminating play between them. Further, the gear train 42
The drive gear 42a provided in the above is restricted from moving in the axial direction, and a female screw is formed on the inner periphery thereof. A screw shaft 43 whose one end is fixed to the lens support cylinder 50 is screwed into the female screw, and the drive gear 42
A and the screw shaft 43 form a feed screw mechanism. Therefore, when the rear group movement motor 30 is rotationally driven to rotate the drive gear 42a in either forward or reverse directions, the screw shaft 43 moves forward and backward with respect to the drive gear 42a, and is supported by the lens support barrel 50, that is, the support barrel 50. The rear lens group L2 moves relative to the front lens group L1.

The shutter blade support ring 46 has a photographing opening 46a on the front wall thereof, and faces the rectilinear guide portion 40c of the shutter mount 40 on the outer peripheral portion thereof, and slides the rectilinear guide member 22 from the inner surface in the radial direction. Deflection control surface that guides freely (falling prevention surface)
46c (see FIGS. 9 and 10). That is,
The shutter blade support ring 46, which is a part of the member forming the AF / AE shutter unit 21, has a portion exposed from the rectilinear guide portion 40c slidably supporting the inner peripheral surfaces of the pair of guide leg portions 22b. It is configured as a drop-out prevention surface. The flexure restricting surface 46c is formed in a pleated shape so as to correspond to the guide leg portion 22b whose inner peripheral surface is pleated.

Since the linear guide member 22 is entirely made of a synthetic resin material, the guide leg portion 22b is flexible and may be bent inward in the radial direction of the annular portion 22a by a force applied during zooming. However, according to the straight guide mechanism having the above-described configuration, the bending restriction surface 46c having a shape surrounding the rear group lens L2.
However, in order to control the flexural deformation of the guide leg portion 22b from the lens storage position of FIG. 9 to the lens extension position of FIG. 10, the guide leg portion 22b comes off the straight guide portion 40c and falls off. Does not occur.

The restricting portion corresponding to the bending restricting surface 46c has conventionally been formed as a member different from the shutter unit for supporting the shutter unit on the rectilinear barrel. Therefore, the number of parts is increased by the amount of this member, and it is difficult to further reduce the size of the zoom lens barrel. However, the AF / AE shutter unit 21 to which the present invention is applied constitutes the shutter unit 21. Since the deflection regulating surface 46c is formed on the shutter blade support ring 46 itself which is a part of the member, the number of parts can be reduced. Therefore, it is possible to further reduce the size of the zoom lens barrel 10.
Further, since the shutter blade support ring 46 having a shape surrounding the rear group lens L2 can be formed long in the optical axis direction, a sufficient stroke of the bending restriction surface 46c with respect to the guide leg portion 22b can be taken.

Further, in front of the shutter mount 40, the motors 29 and 30 supported by the shutter mount 40 are mounted.
Pressing members 53 and 55 for pressing the like are screwed.
Motors 29 and 30 and photo interrupters 56 and 57 are connected to the flexible printed circuit board 6 whose one end is fixed to the shutter mount 40. When the first to third movable lens barrels 20, 19, 16 and the AF / AE shutter unit 21 and the like are assembled, the straight guide cylinder 17
An aperture plate 23 is fixed to the rear end surface of the lens barrel, and an annular retaining member 33 is fitted to the front end of the fixed lens barrel block 12.

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

The present zoom lens camera operates as follows. When the power switch (not shown) is turned on in the lens housed state of FIG. 9 in which the zoom lens barrel 10 is most retracted, the whole movement motor 25 is driven to rotate a little in the forward direction. 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 sets the zoom lens wide. The camera is ready to shoot at the edge.

When the zoom operation means 62 is operated to the tele side in this photographing possible state, the whole movement motor 25 is rotationally driven in the positive direction through the whole movement motor control means 60, and the driving pinion 15 and the outer peripheral gear 16b are used. The third movable lens barrel 16 is rotated in the feeding 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 respect to the third movable lens barrel 16, the lens moves forward along the optical axis in a state where it does not relatively rotate. At this time, the second movable lens barrel 19
Attaches the follower pin 18 to the lead groove 17b and the straight guide groove 1
By being engaged with 6c at the same time, the third movable lens barrel 16 is relatively rotated in the same direction and relatively moved forward of the optical axis with respect to the movable lens barrel 16. Also, the first movable lens barrel 20 is
Since the linear guide member 22 linearly guides and the follower pin 24 is moved and guided by the lead groove 19c, the second movable lens barrel 19 and the AF / AE shutter unit 21 together with the fixed lens barrel block 12 do not rotate relative to each other. Advance to the front of the optical axis.

At the time of this advance, the first movable lens barrel 20, that is, A
Even if the guide leg portion 22b of the rectilinear guide member 22 that guides the F / AE shutter unit 21 in the rectilinear direction tries to bend inward in the radial direction by the force applied during zooming, it is a part of the member that constitutes the shutter unit 21. The deflection regulating surface 46c provided on the shutter blade support ring 46 is provided on the guide leg 2
The bending deformation of 2b is restricted. Therefore, there is a problem that the guide leg portion 22b comes off from the straight-ahead guide portion 40c and falls off.
It is surely prevented.

Since the rear lens group moving motor 30 is not driven while the zoom lens barrel 10 is driven in this way, the front lens group L1 and the rear lens group L2 are integrally integrated with each other while keeping a constant distance from each other. In the direction (see FIG. 8). The focal length set by the zoom operation means 31 is displayed by the display means (not shown).

When the release button is pushed one step at an arbitrary focal length set by the zoom operating 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, and the whole moving motor 25 is moved. And the rear lens group moving motor 30 are moved in consideration of the amount of movement obtained from the subject distance information by the distance measuring device 64 and the amount of movement obtained from the focal length information set by the zoom operation means 31. The front lens group L1 and the rear lens group L2 are moved by an amount to set the focal length and focus the subject. When the release button is pressed twice in this state, the AE motor 2 is operated via the AE motor control means 66.
9 rotationally drives the annular drive member 49 in accordance with the subject brightness information from the photometric device 65, and drives the shutter 27 so as to satisfy a predetermined exposure. After completion of the shutter release, both the whole movement motor 25 and the rear group movement motor 30 are immediately driven to return the front group lens L1 and the rear group lens L2 to the state before the shutter release.

When the zoom operating means 62 is operated to the wide side, the whole moving motor 25 is rotationally driven in the reverse direction, and
The movable lens barrel 16 is rotated in the retracting direction and retracted into the fixed lens barrel block 12 together with the linear guide barrel 17. At the same time, the second movable lens barrel 19 is retracted with respect to the movable movable lens barrel 16 while rotating in the same direction as the third movable lens barrel 16.
The movable lens barrel 20 has a position A relative to the rotating second movable lens barrel 19.
It is pulled in 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. Then, when the power switch is turned off after the zoom lens has moved to the wide end position, the zoom lens barrel 10 is retracted to the lens storage position shown in FIG. 11 by the overall movement motor 25 that is rotationally driven based on this.

[0042]

As described above, according to the present invention, a part of the members constituting the shutter unit is provided with a drop-out preventing surface which engages with the rectilinear guide member from the inside in the radial direction, so that the number of parts is reduced. Therefore, the zoom lens barrel can be further downsized.

[Brief description of 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 that of FIG. 1 of a main part of the linear guide mechanism.

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

FIG. 4 is a perspective view showing a state where the AF / AE shutter unit of the zoom lens barrel is assembled to the first moving lens 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 extended 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 same 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.

[Explanation of symbols]

10 zoom lens barrel (lens barrel) 20 first moving barrel (straight barrel) 21 AF / AE shutter unit (shutter unit) 22 straight guide member 22b guide leg 27 shutter 27a shutter blade 40 shutter mount (outer frame) Ring member 40b Leg part (fixed base) 40c Straight advance guide part (notch) 46 Shutter blade support ring 46c Bending restriction surface (falling prevention surface)

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[Procedure amendment]

[Submission date] March 27, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claim 1

[Correction method] Change

[Correction contents]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] Claim 2

[Correction method] Change

[Correction contents]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a shutter unit; a straight advancing cylinder that fixes the shutter unit and moves in the direction of the optical axis; In a lens barrel having a rectilinear guide member for guiding to a guide, a part of a member constituting the shutter unit is provided with a drop-out preventing surface that engages with the rectilinear guide member from the inside in the radial direction. There is.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Change

[Correction contents]

A shutter unit is provided with an outer frame annular member made of synthetic resin; located inside the outer frame annular member,
A plurality of fixed bases each having a shutter blade support ring for rotatably supporting the shutter blades, wherein the outer frame annular member is fixed to the inner surface of the straight-moving cylinder; A cutout for receiving a member; and a straight guide surface on one side of the cutout, the straight guide surface engaging with the straight guide member in a direction parallel to the optical axis. Formed, facing the notch of the outer frame annular member,
The straight-ahead guide member may be configured to be guided slidably in the radial direction from the inside.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

A third movable lens barrel 16 is screwed onto the inner circumference of the fixed lens barrel block 12. This third movable lens barrel 16
Is a plurality of straight guide grooves 16 extending in the optical axis direction on the inner peripheral surface.
c, and has a male helicoid 16a that meshes with the female helicoid 12a of the fixed 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 a length in the axial direction that meshes with the outer peripheral gear 16b in the entire movement range in the optical axis direction.

[Procedure correction 6]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

A second movable lens barrel 19 is fitted on the inner circumference of the linear guide barrel 17. The second movable lens barrel 19 has a plurality of lead grooves 19 on the inner peripheral surface thereof, the lead grooves 19 having a reverse inclination to the lead grooves 17b.
c has a plurality of follower protrusions 19a having a trapezoidal cross-section, and a follower pin 18 located on the follower protrusions 19a. The follower pin 18 includes a ring member 18a and a center fixing screw 18b that supports the ring member 18a on the follower protrusion 19a. The follower protrusion 19a is
Slidably fitted in the lead groove 17b of the straight guide cylinder 17,
The follower pin 18 is the linear guide groove 1 of the third movable lens barrel 16.
6c is slidably fitted. Therefore, when the third movable lens barrel 16 rotates, the second movable lens barrel 19 rotates and moves straight in the optical axis direction.

[Procedure amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction contents]

The shutter mount 40 further has an AE gear train 45 that transmits the rotation of the AE motor 29 to the shutter 27.
And the rotation of the rear group movement motor 30 to 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 photo interrupter 57 and the rotary plate 59 constitute an encoder for the rear group moving motor that detects the rotation of the rear group moving motor 30, and the photo interrupter 56 and the rotary plate 58 constitute the AE motor 29.
The encoder for the AE motor that detects the rotation of the is configured.

[Procedure amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0030

[Correction method] Change

[Correction contents]

At the rear of the shutter blade support ring 46, a lens support cylinder 50 supported by the shutter mount 40 via slide shafts 51 and 52 so as to be relatively movable is arranged. The shutter mount 40 and the lens support cylinder 50 are urged to move away from each other by the coil spring 3 fitted to the slide shaft 51, thereby removing 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 whose one end is fixed to the lens support cylinder 50 is screwed into this female screw, and these drive gears 42a are
The screw shaft 43 and the screw shaft 43 constitute a feed screw mechanism. Therefore, when the rear group movement motor 30 is rotationally driven to rotate the drive gear 42a in either forward or reverse directions, the screw shaft 43 moves forward and backward with respect to the drive gear 42a, and is supported by the lens support barrel 50, that is, the support barrel 50. The rear lens group L2 moves relative to the front lens group L1.

[Procedure amendment 9]

[Document name to be amended] Statement

[Correction target item name] 0040

[Correction method] Change

[Correction contents]

When the release button is pushed one step at an arbitrary focal length set by the zoom operating means 62, 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, and the whole moving motor 25 is moved. And the rear lens group moving motor 30 are moved in consideration of the amount of movement obtained from the subject distance information by the distance measuring device 64 and the amount of movement obtained from the focal length information set by the zoom operation means 62. The front lens group L1 and the rear lens group L2 are moved by an amount to set the focal length and focus the subject. When the release button is pressed twice in this state, the AE motor 2 is operated via the AE motor control means 66.
9 rotationally drives the annular drive member 49 in accordance with the subject brightness information from the photometric device 65, and drives the shutter 27 so as to satisfy a predetermined exposure. After completion of the shutter release, both the whole movement motor 25 and the rear group movement motor 30 are immediately driven to return the front group lens L1 and the rear group lens L2 to the state before the shutter release.

[Procedure amendment 10]

[Document name to be amended] Drawing

[Correction target item name] Fig. 1

[Correction method] Change

[Correction contents]

FIG.

[Procedure amendment 11]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

[Fig. 2]

[Procedure amendment 12]

[Document name to be amended] Drawing

[Correction target item name] Figure 3

[Correction method] Change

[Correction contents]

[Figure 3]

[Procedure amendment 13]

[Document name to be amended] Drawing

[Correction target item name] Fig. 4

[Correction method] Change

[Correction contents]

FIG. 4

[Procedure Amendment 14]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

[Figure 5]

[Procedure Amendment 15]

[Document name to be amended] Drawing

[Correction target item name] Fig. 8

[Correction method] Change

[Correction contents]

[Figure 8]

[Procedure Amendment 16]

[Document name to be amended] Drawing

[Correction target item name] FIG.

[Correction method] Change

[Correction contents]

FIG. 11

Claims (2)

[Claims] 1. A shutter unit; a straight-moving barrel for fixing the shutter unit and moving in the optical axis direction; and a straight-moving guide member for restricting rotation of the straight-moving barrel to guide only straight-moving movement. In the lens barrel, a straight guide mechanism for the lens barrel, characterized in that a drop-preventing surface that engages with the straight guide member from the inside in the radial direction is provided in a part of a member constituting the shutter unit. 2. The shutter unit according to claim 1, wherein an outer frame annular member made of synthetic resin; a shutter blade support ring located inside the outer frame annular member and rotatably supporting the shutter blades; The outer frame annular member has a plurality of fixing bases that are in contact with the inner surface of the straight-moving cylinder and are fixed to the straight-moving cylinder; and notches that are located between these fixing bases and that receive the straight-moving guide member. A linear guide surface in a direction parallel to the optical axis that engages with the linear guide member on one side of the notch; and the shutter blade support ring faces the notch of the outer frame annular member, A straight-movement guide mechanism for a lens barrel having a drop-out preventing surface for slidably guiding a straight-movement guide member from an inner surface in a radial direction.