JPH07111497B2 - Storage device for focus ring for manual operation in zoom lens - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for storing a focus ring for manual operation in a zoom lens having a manual and automatic focus adjustment mechanism, and more specifically, an optical axis direction of the zoom ring. The present invention relates to a storage device in which the focus ring for manual operation can be switched between an exposed state and a non-exposed state by moving the.

[Prior Art] A conventional focus ring for manual operation in a zoom lens having a manual and automatic focus adjusting mechanism is generally left exposed to the outside, and this mechanism is used when the automatic focus adjusting mechanism operates. Rotates at high speed in conjunction with. If your hand comes into contact with the focus ring that rotates at high speed, it will cause blurring when holding the camera body and lens, which is not preferable and will also add an excessive load to the automatic focus adjustment mechanism. This may cause a malfunction such as a malfunction of the adjusting mechanism.

For the above reason, in the conventional zoom lens, the focus ring is provided at the forefront part of the lens barrel, and the width of the ring is reduced.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional coping method, there is a problem that the operability of manual focus adjustment is significantly deteriorated.
Further, the problem of contact between the focus ring and the hand described above is not completely overcome.

The present invention has been made based on this point of view, and provides a structure of a focus ring for manual operation that does not come into contact with the hand during automatic focus adjustment and does not impair operability during manual focus adjustment. The purpose is to

[Means for Solving the Problems] In order to achieve the above object, according to the present invention, zooming is performed by rotating a zoom ring, and a zoom lens having a manual and automatic focus adjustment mechanism is provided for manual operation. The focus ring was dimensioned for telescopic insertion into the zoom ring. Further, the zoom ring is movable in the optical axis direction, and when the zoom ring is located at one end of the range of movement in the optical axis direction, it covers and houses the externally exposed portion of the focus ring and is located at the other end. When this is done, the externally exposed portion is released so that it can be grasped.

[Operation] With the storage device according to the present invention having the above-described configuration, when the automatic focus adjustment mechanism is activated, the zoom ring is moved to one end in the optical axis direction to bring the focus ring into a non-exposed state. Does not come into contact with the hand even when the camera rotates at a high speed in conjunction with the automatic focus adjustment mechanism, and during manual focus adjustment, move the zoom ring to the other end in the optical axis direction to expose the focus ring. In this state, the focus can be adjusted by gripping it, so that the operability of manual focus adjustment is not particularly impaired.

[Embodiment] FIG. 1 and FIG. 2 are sectional views showing a zoom lens having an embodiment of a manually operated focus ring storage device according to the present invention. In the figure, in order to clarify the relationship between the zoom ring and the focus ring, most of the automatic focusing mechanism is omitted and shown schematically.

Four lens groups (shown as a single lens for convenience of illustration) are arranged in the lens barrel 10 of the zoom lens so that the optical axes are aligned, and these are arranged from the object side to the objective lens group.
The order is L1, variator lens group L2, compensator lens group L3, and relay lens group L4.

A variator lens group L2 and a compensator lens group L3 are usually used for zooming, and zooming is performed by relative approach and separation of both lens groups L2 and L3 in the optical axis direction. The variator lens group L2 is connected to the cam barrel 16 by the supporting and moving piece 12, and the compensator lens group L3 is connected to the cam barrel 16 by the supporting and moving piece 14. Both pieces
12, 14 are movably arranged in a cam groove (not shown) of a predetermined shape formed in the cam barrel 16, and when the cam barrel 16 is rotated via a zoom ring 18 described later, both pieces 12 , 14 move along the cam groove, and both lens groups L2, L3 relatively approach,
It is designed to separate from each other.

A zoom ring 18 is arranged around the outer periphery of the lens barrel 10 and is connected to the cam barrel 16 by a connecting pin 20. Connecting pin 20
The upper end of the zoom ring 18 engages with the long groove 22 formed in the zoom ring 18, and therefore, within the range of the stroke A allowed by the long groove 22, the zoom ring 18 is manually operated with respect to the rest of the lens barrel 10 in the optical axis direction. It is possible to move to. Further, in the moving range of the zoom ring 18, the connection between the zoom ring 18 and the cam barrel 16 by the connecting pin 20 is maintained, so that the zoom ring 18 and the cam barrel 16 always operate integrally in the rotational direction.

A circular hole 24 is formed at one position on the circumference of the zoom ring 18 and a lock release button 26 is provided therein. Button 26
Is supported by a leaf spring 30 attached to the inside of the zoom ring 18 by a screw 28 in a cantilever manner.
Elastically anchored in place within 24. At this predetermined position, the inner end surface of the button 26 is aligned with the inner surface of the recess 32 inside the zoom ring 18 formed around the button 26. Button again
A lock pin 34 is arranged inside the lens barrel 10 so as to face 26, and the pin 34 is also supported by a leaf spring 38 attached to a screw 36. The pin 34 elastically projects into the recess 32 so as to face the inner end surface of the button 26 under the action of the leaf spring 38, and locks the zoom ring 18 at a predetermined position in the optical axis direction shown in FIG.

On the camera body side, a focus ring 40 for manual operation is arranged in a nesting manner between the cam barrel 16 and the zoom ring 18. The focus ring 40 is connected to a support member 42 of the objective lens group L1 via a manual drive unit (not shown) and a drive unit (for example, as shown in FIG. 3 described later) of an automatic focus adjustment mechanism,
By the rotation, the objective lens group L1 is moved in the optical axis direction so that focus adjustment can be performed. A fixed collar 46 that covers a part of the focus ring 40 is provided with a window 44 for visually recognizing the operation of the focus ring 40 in the state shown in FIG. 1, and the window 44 is closed by a transparent plate such as plastic. .

In the above zoom lens, in the state shown in FIG. 1, the focus ring 40 for manual operation is completely covered and housed inside the zoom ring 18, and in this state, the automatic focus adjustment mechanism (not shown) used. That is, since the focus ring 40 is in a completely unexposed state, even if it rotates at a high speed in conjunction with the automatic focus adjustment mechanism, the hand may come into contact with it and cause camera shake, or There is no excessive load applied to it. Further, at this time, since the indication scale of the rangefinder of the focus ring 40 is completely invisible, it is confirmed whether the focus ring 40 is operating properly through the window 44 of the collar 46.

When the lock release button 26 is pressed from the state shown in FIG. 1, the lock pin 34 sinks and the zoom ring 18 can be moved to the subject side. In the illustrated embodiment, the zoom ring 18 can be moved to the end of the lens barrel 10 on the object side as shown in FIG. 2, and at this position is lightly locked by a suitable click member (not shown).

In the state shown in FIG. 2, the focus ring 40 is released from the covering of the zoom ring 18 by the same width as the moving stroke A of the zoom ring 18 to form the external exposed portion 48. Therefore, the objective lens L1 can be moved by gripping and rotating the externally exposed portion, that is, manual focus adjustment can be performed.

When the zoom ring 18 is returned to the end position on the camera body side shown in FIG. 1 from the state shown in FIG. 2 against the locking force of the click member, the lock pin 34 is urged by the spring 38 to cause the zoom ring 18 to move. It projects into the recess 32 of 18 and again locks the zoom ring 18 in the state shown in FIG.

FIG. 3 is a diagram more specifically showing the relationship between the drive units of the manual and automatic focus adjustment mechanisms and the storage device according to the present invention. In this diagram, according to the embodiment shown in FIGS. 1 and 2, The focus ring 40 for manual operation is shown as provided on the camera body side. In the figure, in order to avoid duplication of explanation, the same reference numerals are given to the substantially same members as those described above, and the description thereof will be omitted.

In the lens barrel 10, a shaft 50 is arranged between the cam barrel 16 and the zoom ring 18 along the optical axis direction, and gears 52 and 54 are fixedly provided at both ends thereof. The gear 52 on the camera body side meshes with a gear 58 fixed to the output shaft of the drive motor 60, while the gear 54 on the subject side meshes with a gear portion formed on the cam barrel 56 of the objective lens group L1. Therefore, when the separately provided switch member is turned on to operate the automatic focus adjustment mechanism, the motor 60 is controlled by the mechanism and the rotational force is applied to the cam barrel 56 in the order of the gear 52, the shaft 50, and the gear 54. When transmitted, the objective lens unit L1 is driven in the optical axis direction, and automatic focus adjustment becomes possible. In the illustrated state, the focus ring 40 is covered and housed by the zoom ring 18 and is in a completely unexposed state. In this state, automatic focus adjustment is performed.
The cam barrel 56 of the objective lens group L1 is covered with the collar 62, so that it does not come into contact with a hand or the like.

The gear 52 also meshes with a gear portion formed on the camera body side of the focus ring 40. Therefore, move the zoom ring 18 to the left in the figure by the stroke A to move the focus ring.
If 40 is exposed and the exposed portion of the focus ring 40 is gripped and rotated, manual focus adjustment becomes possible.

FIG. 4 is a view showing a modified embodiment of the present invention, in which a manual operation focus ring is provided on the subject side. In the figure, in order to avoid duplication of explanation, the same reference numerals are given to the substantially same members as those described above, and the description thereof will be omitted.

In this embodiment, the cam barrel 56 of the objective lens unit L1 also serves as the focus ring for manual operation, and the zoom ring 18
b extends to the subject side so that it can be covered. The structure and operation mode of the drive part of the manual and automatic focus adjusting mechanism are substantially the same as those of the embodiment shown in FIG. The illustrated state is a state in which the zoom ring 18b completely covers and houses the cam barrel (focus ring) 56, and therefore automatic focus adjustment is performed in this state. Further, when the zoom ring 18b is moved rightward in the figure by the stroke A, the cam barrel 56 is exposed and the manual focus adjustment becomes possible.

EFFECTS OF THE INVENTION According to the storage device for the manual operation focus ring according to the present invention, the focus ring can be easily brought into the non-exposed state by the movement of the zoom ring in the optical axis direction during the automatic focus adjustment. Even if the scrap ring rotates at high speed in conjunction with the automatic focus adjustment mechanism, it does not come into contact with the hand and cause various problems. Further, during manual focus adjustment, the focus ring can be switched to the exposed state by moving the zoom ring in the opposite direction to that described above, and therefore operability thereof is not particularly impaired during manual focus adjustment.

[Brief description of drawings]

1 and 2 are sectional views showing a zoom lens having an embodiment of a storage device for a focus ring for manual operation according to the present invention, and FIG. 3 is a drive section of a manual and automatic focus adjusting mechanism and the present invention. FIG. 4 is a diagram showing the relationship with the storage device according to the present invention more specifically, and FIG. 4 is a diagram showing a modified embodiment of the present invention. 10 …… Body tube, 16 …… Cam tube, 18,18b …… Zoom ring,
26 …… Unlock button, 40 …… Focus ring, 50
…… Shaft, 56 …… Cam tube (focus ring), 60
...... Motor, L1 …… Objective lens group, L2 …… Variator lens group, L3 …… Compensator lens group, L4 …… Relay lens group

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G03B 3/00 A

Claims (1)

[Claims] 1. A zoom lens having zooming by rotating a zoom ring and having a manual and automatic focus adjusting mechanism. The focus ring for manual operation is dimensioned so that it can be telescopically inserted into the zoom ring. , The zoom ring is movable in the optical axis direction, and when the zoom ring is located at one end of the range of movement in the optical axis direction, the zoom ring is covered and housed at the externally exposed portion of the focus ring, and is located at the other end. A storage device for a manual operation focus ring, characterized in that the externally exposed portion is released so as to be grippable at the time.