JP2931280B2 - Zoom lens device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens device used for an electronic still camera, a video camera and the like.
More specifically, the present invention relates to a zoom lens device provided with a flexible substrate for making an electrical connection between an internal component of a moving cylinder that moves along the optical axis direction and a camera body.

[0002]

2. Description of the Related Art In a camera having a built-in zoom lens device, while achieving compactness, it is desired to increase the zoom ratio, and the amount of extension of a lens barrel is increased.

For example, in a two-stage barrel structure, a fixed barrel fixed to a camera body, an intermediate barrel that advances and retreats in the optical axis direction inside the fixed barrel, and an optical axis inside the intermediate barrel with respect to the intermediate barrel. It has a movable cylinder that moves forward and backward. In addition to the taking lens, electronic components such as a shutter mechanism are built in the movable cylinder. Therefore, conventionally, a flexible substrate for making electrical connection with an electronic component is disposed between the inside of the movable cylinder and the camera body. One end of this flexible substrate is connected to the electronic components of the movable cylinder, and the rear end is guided into the camera body. Near the rear end, in addition to the extension of the movable cylinder, the extension of the intermediate cylinder is included. It was arranged in an S-shaped slack by the length of the wire. By doing so, the flexible substrate is pulled out from the slack portion in accordance with the extension of the movable tube and the intermediate tube, and when retreating, the flexible substrate returns to the S-shaped slack state again.

[0004]

However, when the amount of extension of the movable cylinder or the intermediate cylinder is increased by increasing the zoom ratio, the length of the flexible substrate to be slackened accordingly. If the length of the flexible substrate to be relaxed is increased, twisting or the like is likely to occur due to advance and retreat of the lens barrel. Further, if the slack portion is formed by bending the S-shaped portion in many steps, a large space is required for the thickness, and there is a drawback that it becomes an obstacle to downsizing.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and safely processes wiring of a flexible substrate as the lens barrel is extended, and contributes to miniaturization of the entire apparatus. It is an object of the present invention to provide a zoom lens device capable of performing the following.

[0006]

In order to achieve the above object, a zoom lens device according to the present invention comprises: a gear portion provided on an intermediate cylinder; An intermediate cylinder rotating member for rotating the intermediate cylinder by moving the engagement position with the gear portion along the optical axis direction together with the intermediate cylinder through the provided opening; A rectilinear guide member engaged in the rotation direction, the rear end of which is bent into an L-shape and is exposed from the opening, and which moves with the advance and retreat of the intermediate cylinder and linearly guides the advance and retreat of the movable cylinder; Is connected to the internal part of the movable cylinder through the space between the linear guide member and the key groove, and the other end is bent between the rear end side of the intermediate cylinder and the rear end of the linear guide member. Exposed from the opening, with a constant length between one end and the other end In which bending position of and a flexible substrate that varies along the optical axis direction together with movement of the straight guide member.

[0007]

1 to 3 show a first embodiment of the present invention.
This embodiment shows an embodiment in which a zoom mechanism includes a two-group zoom lens including a front lens group 20 including five lenses and a rear lens group 21 including three lenses. Zooming is performed by moving back and forth in the direction of the axis P.

The zoom lens barrel has a fixed barrel 23 integrally formed with the camera body, an intermediate barrel 24 helicoidally coupled inside the fixed barrel 23, and a movable cylinder helicoidally coupled inside the intermediate barrel 24. And a cylinder 25. In addition, since the camera body integrally formed with the fixed cylinder 23 is integrally provided with a wall surface 23c forming a film cartridge chamber, a film feeding gear, and the like, conventionally, the camera body and the fixed cylinder are formed as separate members. In the present embodiment, the miniaturization of the shape of the camera is improved as compared with the camera having the above configuration. Reference numeral 22 denotes a front cover that covers the camera body.

Conventionally, a film feeding gear is provided on a bearing provided in a camera body. However, although not shown in the present embodiment, the film feeding gear is formed by utilizing a part of the fixed cylinder 23. It is possible to support.

The front lens group 20 is fixed to the movable barrel 25 by a well-known bayonet connection or the like.
Behind the lens group 0, a rear group lens 21 is incorporated in a rear group lens frame 29 via a rear group lens frame 28. Reference numeral 26 denotes a shutter block.

More specifically, as shown in FIG. 1, the rear lens frame 28 is fixed to the movable barrel 25, and a female helicoid 28a is formed inside. This female helicoid 28a
Is screwed with a male helicoid 29a formed on the outer periphery of the rear lens frame 29. A gear 29b is formed on the peripheral surface of the male helicoid 29a, and the gear 29b is driven by a rear lens driving motor 26a built in the shutter block 26 by gears 26b, 26c, 26d, 26e.
Is transmitted via Therefore, the rear group lens frame 29 incorporating the rear group lens 21 is provided with a rear group lens driving motor 30.
The rear group lens frame 29 is rotated by the drive of, and advances and retreats according to the lead of the male helicoid 29a provided on the rear group lens frame 29. Note that the rear lens group 21 is also moved forward and backward during focusing.

A male helicoid 2 is provided on the outer periphery of the movable cylinder 25.
5a, and a female helicoid 24a provided in the intermediate cylinder 24 is screwed into the male helicoid 25a. The movable cylinder 25 advances and retreats in accordance with the lead of the male helicoid 25a, and the movable cylinder 25 has a groove 25b provided on the inner peripheral surface thereof fitted with a rectilinear guide member 35 described later in detail. Move straight back and forth along. Reference numeral 25e denotes a cover frame attached to the front end side of the movable barrel 25, and reference numeral 25d denotes a lens window provided on the cover frame 25e.

The intermediate cylinder 24 is provided at the rear end side of the outer periphery with a fixed cylinder 23.
Is provided with a male helicoid 24b screwed into a female helicoid 23a formed on the inner periphery of the male cylinder. When the intermediate cylinder 24 is rotated by an intermediate cylinder rotating member 33 described later in detail, the male helicoid 24b leads. Advance and retreat according to On the front end side of the male helicoid 24b, a gear portion 24c is formed with a constant width in the optical axis P direction.

As shown in detail in FIG. 2, the fixed cylinder 23 is provided with an opening 23b, which is formed along the optical axis P. Outside the opening 23b, a shaft 30 and guide shafts 31, 32 are fixed to the fixed cylinder 23 and the front cover 22 in parallel to the optical axis P.
An intermediate cylinder rotating member 33 is rotatably inserted into the shaft 30. The intermediate rotating member 33 has a gear 3 at one end.
3a and a helical gear 33a, which is helically protruded from the front of the gear 33b to the other end thereof, are integrally formed. The drive of the lens motor 34 provided in the fixed cylinder 23 is transmitted to the gear 33a, whereby the intermediate cylinder rotating member 33 rotates. The spiral gear 33a meshes with the gear portion 24c through the opening 23b,
The intermediate cylinder 24 is rotated by driving the lens motor 34. The rotation of the intermediate cylinder rotation member 33 causes the spiral gear 3
3a is displaced, but the displacement of the helical gear 33a is
4, the meshing portion between the helical gear 33a and the gear portion 24c moves in the same phase as the intermediate cylinder advances and retreats.

The guide rods 31 and 32 are loosely inserted into one end of a linear guide member 35 whose other end is fitted into the groove 25b through the opening 23b. A guide cylinder 35a is provided integrally with the portion of the straight guide member 35 through which the guide rod 31 is freely inserted.
Two guide pins 35b are implanted in 5a. These guide pins 35b are in contact with both walls of the spiral gear 33a, and move the linear guide member 35 along the guide rod 31 in response to the displacement of the spiral gear 33a. Accordingly, the linear guide member 35 moves in the same phase as the intermediate cylinder 24 advances and retreats. A flexible board 36 is inserted between the straight guide member 35 and the movable cylinder 25. The other end of the flexible board 36 is connected to the shutter block 26, and one end of the flexible board 36 is disposed in the camera body via a pressing roller 35c provided on one end of the linear guide member 35. It is connected to a circuit and the like. The length of the flexible board 36 is constant, and the pressing roller 35c moves to move the flexible board 36 in the same manner as the movement of the straight guide member 35.

Next, the operation of the above configuration will be briefly described. In FIG. 1 showing the state of the collapsed position of the zoom lens apparatus according to the first embodiment, in this state, the movable barrel 25 and the intermediate barrel 24 are housed in the fixed barrel 23, and the helical gear 33a and the gear portion 24c Is located on the rear end side in the opening 23b of the fixed cylinder 23.

Further, two guide pins 35b sandwiching both walls of the spiral gear 33a are located on the rearmost end side of the spiral gear 33a. Therefore, the straight guide member 35 is located at the rear end side of the guide rods 31, 32, and the flexible board 36 is drawn into the camera body by the pressing roller 35c.

In the case of extending the zoom lens device from the retracted position to the projecting position shown in FIG. 3, the lens motor 34 is driven. The lens motor 34 drives the intermediate cylinder rotating member 33 to rotate clockwise when viewed from the direction of the lens window 25d. Thus, when the intermediate cylinder rotating member 33 rotates, the helical gear 33 is rotated.
“a” is displaced while rotating the intermediate cylinder 24 with respect to the fixed cylinder 23 via the gear portion 24c.

The intermediate cylinder 24 moves forward by its own rotation in accordance with the lead of the male helicoid 24b. Thus, the meshing portion between the helical gear 33a and the gear portion 24c moves in the same phase as the movement of the intermediate cylinder 24.

The rotation of the intermediate cylinder 24 causes the movable cylinder 25 to move forward with respect to the intermediate cylinder 24 in accordance with the lead of the male helicoid 25a. The movement of the movable cylinder 25 moves along the straight guide member 35. Since the straight guide member 35 moves in the same manner as the displacement of the spiral gear 33a via the guide pin 35b, the extension of the movable cylinder 25 can be increased.

Further, since one end of the flexible substrate 36 is connected to the shutter block 26, the flexible substrate 36 is pulled out of the camera body as the movable barrel 25 moves. At this time, since the pressing roller 35c moves in the same manner as the movement of the straight guide member 35, the flexible substrate 36
It guides the movement of a person safely. As a result, as shown in FIG. 3, the zoom lens barrel is in a protruding position state, and the extension of the zoom lens is completed. The rear group lens 21 is advanced and retracted in accordance with the extension of the zoom lens as described above.

Next, when changing from the state shown in FIG. 3 to the state shown in FIG. 1, the lens motor 34 is driven so as to rotate the intermediate cylinder rotating member 33 counterclockwise when viewed from the direction of the lens window 25d. Thereby, as described above, the spiral gear 33 is used.
a, the intermediate cylinder 24 retreats in the same manner as the displacement of
The movable cylinder 25 is retracted by the rotation of.

Although it is necessary to retract the flexible substrate 36 into the camera body as the movable cylinder 25 retracts, the flexible substrate 36 can be safely retracted because the pressing roller 35c moves as the rectilinear guide member 35 retracts. Becomes

Further, in the first embodiment, the intermediate cylinder rotating member 33 is an example integrally formed. However, as shown in FIG. 4, a spiral gear 33a formed on the peripheral surface is divided at least within 360 ° around the periphery. It may be composed of two or more parts.

Next, a second embodiment of the zoom lens apparatus according to the present invention will be described with reference to FIG. The configuration of the zoom lens apparatus according to the second embodiment includes a fixed barrel 23 integrally formed with the camera body, an intermediate barrel 24 helicoidally coupled inside the fixed barrel 23, and an intermediate barrel 24.
And a movable cylinder 25 which is helicoidally coupled to the inside thereof, and the same members as those already described in the first embodiment are denoted by the same reference numerals.

In the second embodiment, the structure of the rotating means for rotating the intermediate cylinder 24 is constituted by the spline shaft 40 provided in the camera body and the lead screw 41 arranged outside the spline shaft 40. I have. These are arranged in parallel to the optical axis P and rotatably.

The lead screw 41 has a lens motor 34
A gear 41a to which the driving of the lead screw 41 is transmitted is provided, and the gear 41a and the lead screw 41 rotate integrally.
Further, the gear 41a meshes with a gear 40a provided on the spline shaft 40, and the gear 40a and the spline shaft 40
And rotate together.

A bush 42 is attached to the lead screw 41.
The bush 42 has a protrusion 4 on its front end side.
2a is provided, and the rectilinear guide member 35 is fixed to the rear end side. Since the bush 42 fixes the rectilinear guide member 35, the bush 42 moves linearly according to the lead of the lead screw 41. The leads of the lead screw 41 are formed so that the movement of the bush 42 is in the same phase as the movement of the intermediate cylinder 24. The spline shaft 40 has an intermediate cylinder 2
A gear member 43 meshing with the fourth gear portion 24c is spline-coupled, and a groove 43a in which the projection 42a is fitted is provided behind the gear member 43.

The operation of the above configuration will be briefly described. The lead screw 41 is rotated by the driving of the lens motor 34 via the gear 41a. The bush 42 moves according to the lead of the lead screw 41, and the movement moves the gear member 43 along the spline shaft 40 via the projection 42a.

The gear member 43 is rotated via the gears 40a and 41a by driving the lens motor 34, and the intermediate cylinder 24 is rotated by the rotation. The intermediate cylinder 24 moves forward and backward according to the lead of the male helicoid 24b by its own rotation. Since the movement of the intermediate cylinder 24 is the same movement as the movement of the gear member 43, the gear member 43 and the gear portion 24 are moved.
The portion meshed with c moves in the same phase as the advance / retreat of the intermediate cylinder 24. In addition, since the linear guide member 35 is fixed to the bush 42, the linear guide member 35 moves in the same phase as the intermediate cylinder 24 advances and retreats.

Further, if the pressing roller 35c described in the first embodiment is provided on the bush 42, the flexible substrate 36 can be moved in accordance with the advance / retreat of the movable cylinder 25, and the same effect as in the first embodiment can be obtained. Things. As described above, in the second embodiment, since the lead screw 41 is used, the spiral gear 33 described in the first embodiment is used.
Since it is easier to manufacture than the intermediate cylinder rotating member 33 provided with a, there is an effect that the component cost is reduced.

Next, a third embodiment of the zoom lens apparatus according to the present invention will be described with reference to FIG. The configuration of the zoom lens apparatus according to the third embodiment includes a fixed barrel 23 integrally formed with the camera body, an intermediate barrel 24 helicoidally coupled inside the fixed barrel 23, and an intermediate barrel 24.
And a movable cylinder 25 which is helicoidally coupled to the inside thereof, and the same members as those already described in the first embodiment are denoted by the same reference numerals.

In the third embodiment, the structure of the rotating means for rotating the intermediate cylinder 24 is constituted by the lead screw 50 provided in the camera body and the two-stage gear 51 arranged outside the lead screw 50. ing. These are arranged in parallel to the optical axis P and rotatably. Gears 50a and 50b are integrally formed with the two-stage gear 51, and the drive of the lens motor 34 is transmitted to the gear 50a.

A gear 51a meshing with the gear 50a is provided at a front end side of the lead screw 50, and the lead screw 50 and the gear 51a rotate integrally. Further, a bush 52 is screwed into the lead screw 50, and the bush 52 advances and retreats according to the lead of the lead screw 50.

The bush 52 is provided with an intermediate cylinder rotating gear 54 rotatable with respect to the bush 52 meshing with both the gear 50b and the gear portion 24c of the intermediate cylinder 24 through the opening 23b. A linear guide member 35 is fixed to the bush 52 at the rear end side of the intermediate cylinder rotating gear 54.

The bush 54 is provided with the straight guide member 35.
Is fixed, and therefore moves linearly according to the lead of the lead screw 51. The leads of the lead screw 51 are formed so that the movement of the bush 52 is in phase with the movement of the intermediate cylinder 24. As a result, the intermediate cylinder rotating gear 54 moves integrally with the bush 52 and the gear 5
0b is a length that allows the movement of the intermediate cylinder rotation gear 54.

The operation of the above configuration will be briefly described. The gears 50a and 50b rotate integrally by driving the lens motor 34. The rotation of the gear 50b causes the rotation of the intermediate cylinder rotating gear 5
4 is rotated, and the rotation of the intermediate cylinder rotating gear 54 rotates the intermediate cylinder 24 via the gear portion 24c. As a result, the intermediate cylinder 24 advances and retreats according to the lead of the male helicoid 24b.

As the gear 50a rotates, the lead screw 51 also rotates via the gear 51a.
2 moves in accordance with the lead of the lead screw 51, and in accordance with the movement of the bush 52, the intermediate cylinder 54 also moves while rotating by the gear 50b. That is, since the movement of the bush 52 moves in the same manner as the movement of the intermediate cylinder 24, the meshing portion between the intermediate cylinder rotation gear 54 and the gear portion 24c is in phase with the advance and retreat of the intermediate cylinder 24. Since the straight guide member 35 also moves integrally with the bush 52, it goes without saying that the same effect as in the first embodiment can be obtained. According to this, the spline shaft 40 used in the second embodiment
Since the two-stage gear 50 is used without using the above, there is an effect that the manufacturing cost is reduced and the cost is reduced.

Next, a fourth embodiment of the zoom lens apparatus according to the present invention will be described with reference to FIGS. In this embodiment, an intermediate cylinder rotating member (not shown) for rotating the intermediate cylinder 24 has a structure as described in the first to third embodiments. Male helicoid 24b, 2
The lead 5a is such that the movement of the movable barrel 25 in the direction of the protruding position is twice as large as the movement of the intermediate barrel 24. Reference numeral 23d denotes a wall surface of the film winding chamber.

As described in the first to third embodiments, the flexible board 36 is also provided with the straight guide member 35.
Move in the same phase as the movement of the first roller, but the pressing roller 35c described in the first to third embodiments is not provided. Even with such a configuration, the flexible substrate 36
Even if the front end side and the rear end side thereof are fixed at a fixed length to the control unit and the shutter block 26 in the camera body, respectively, a U-shape is formed between the rear end side of the intermediate cylinder 24 and the straight guide member 35. The intermediate cylinder 24 follows the advance and retreat of the intermediate cylinder 24 without sagging. Therefore, the first to third
The movement of the flexible substrate 36 can be made to follow the advance / retreat of the intermediate cylinder 24 without using the pressing roller 35c as described in the embodiment, which has the effect of reducing costs.

[0041]

As described above, according to the zoom lens device of the present invention, the linear guide member is provided between the L-shaped linear guide member moving with the advance and retreat of the intermediate cylinder and the key groove provided in the movable cylinder. Since the flexible substrate is passed through so that the bending position changes following the movement of the object, for example, as described in the related art, there is no need to loosen each S-shaped one, and the twist is safe and smooth. Since it can be pulled out or pulled back, and a large space for the slack portion is not required, it can contribute to downsizing.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a zoom lens barrel in a retracted position according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the lens barrel shown in FIG. 1 as viewed from the rear side, and shows a main part in an exploded manner.

FIG. 3 is a cross-sectional view showing a state where a lens barrel shown in FIG. 1 is in a protruding position.

FIG. 4 is an exploded perspective view showing an intermediate cylinder rotating member of another embodiment.

FIG. 5 is a sectional view showing a zoom lens barrel according to a second embodiment of the present invention.

FIG. 6 is a sectional view showing a zoom lens barrel according to a third embodiment of the present invention.

FIG. 7 is a cross-sectional view showing a zoom lens barrel according to a fourth embodiment of the present invention, showing a state in which the lens barrel is retracted within a contour of a camera body.

FIG. 8 is a cross-sectional view showing a zoom lens barrel according to a fourth embodiment, showing a state where the lens barrel projects from the contour of the camera body.

[Explanation of symbols]

 Reference Signs List 23 fixed cylinder 24 intermediate cylinder 20 front lens group 21 rear lens group 25 movable cylinder 33 intermediate cylinder movable member 33a spiral gear 35 rectilinear guide member 35c pressing roller 36 flexible board 40 spline shaft 41, 51 lead screw

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02B 7/02-7/04 G02B 7/08-7/10 G03B 17/02

Claims (1)

(57) [Claims] 1. An intermediate cylinder which is helicoid-coupled to a fixed frame fixed to a camera body and which advances and retreats in the optical axis direction according to the lead of the helicoid by rotating, and a movable cylinder which is helicoid-coupled to the inside of the intermediate cylinder A zoom lens device in which a movable cylinder incorporating a photographic lens by rotating the intermediate cylinder advances and retreats in the optical axis direction in accordance with a helicoid lead provided inside the intermediate cylinder; and a gear unit provided on the intermediate cylinder. An intermediate cylinder rotating member for moving the meshing position with the gear portion along the optical axis direction together with the intermediate cylinder through an opening provided in the fixed cylinder along the imaging optical axis direction to rotate the intermediate cylinder; And the tip engages with the key groove provided in the movable cylinder in the rotational direction,
A rear end is bent into an L-shape and is exposed from the opening, and a linear guide member that moves with the advance and retreat of the intermediate cylinder to linearly guide the advance and retreat of the movable cylinder; one end of the linear guide member and the key; The other end is connected to the internal part of the movable cylinder through the groove, the other end is bent between the rear end side of the intermediate cylinder and the rear end of the rectilinear guide member, and is exposed from the opening. A flexible substrate having a constant length between the other end and a bending position whose bending position changes along the optical axis direction with movement of the straight guide member.