JPH1020175A - Collapsible mount type interchangeable lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a collapsible mount type interchangeable lens barrel which becomes in a collapsible mount state when it is detached from a camera body and becomes in a photographing feasible state when it is attached to the camera body. SOLUTION: The rotating direction of a boom ring (operation ring 5 at the time of setting the lens barrel 1 to the collapsible mount state from the photographing feasible state is made the same as the rotating direction at the time of detaching the lens barrel 1 from the camera body 15, and the rotating direction of the ring 5 at the time of setting the lens barrel 1 to the photographing feasible state from the collapsible mount state is made the same as the rotating direction at the time of attaching the lens barrel 1 to the camera body 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an optical system in which
The present invention relates to a retractable interchangeable lens barrel configured to be able to take a retracted state shorter than the shortest state at the time of photographing.

[0002]

2. Description of the Related Art A retractable interchangeable zoom lens barrel has conventionally been provided as an interchangeable lens barrel for a single-lens reflex camera which is excellent in portability and storage when not in use (for example,
See JP-A-2-25815). The retractable zoom lens barrel has a total length in the optical axis direction by rotating a zoom ring during non-photographing to retract at least a part of the photographing lens (front lens) and its holding frame toward the camera body in the optical axis direction. It is configured to be able to take a state (collapsed state) shorter than the shortest state at the time of shooting.

[0003]

By the way, if the retractable zoom lens barrel is not in the retracted state when detached from the camera body, the lens barrel is brought into the retracted state after the operation of removing from the camera body. An operation to change the lens barrel is necessary, and if this operation is not performed, the portability and storage of the lens barrel deteriorate. If the camera is not in a photographable state when attached to the camera body, an operation of changing the lens barrel to a photographable state after attaching to the camera body is required. Also, if this operation is to rotate the zoom ring in the direction opposite to the direction of rotation when attaching the lens barrel, the feeling of use is unnatural and in addition to this operation, there is a chance to take a photo You may miss it. Such a problem is not limited to a zoom lens barrel that performs a retracting operation with a zoom ring, but may occur in a lens barrel that includes an operation ring and performs the retracting operation with the operation ring.

Accordingly, a technical problem to be solved by the present invention is to provide a collapsible interchangeable lens barrel which is in a collapsed state when detached from a camera body and in a photographable state when attached to the camera body.

[0005]

SUMMARY OF THE INVENTION A retractable interchangeable lens barrel according to the present invention is provided with a retractable operation ring such as a zoom ring and a focus ring, or an operation ring dedicated to a retractable operation. The overall length is configured to be able to take a collapsed state shorter than the shortest state at the time of shooting, is configured to be detachable with respect to the camera body, and in order to solve the above-described technical problem, a lens barrel is provided. When the rotation direction of the operation ring when the lens barrel is changed from the photographable state to the collapsed state is the same as the rotation direction when the lens barrel is removed from the camera body, and when the lens barrel is changed from the collapsed state to the photographable state. The rotation direction of the operation ring is the same as the rotation direction when the lens barrel is attached to the camera body.

[0006]

In the above configuration, the lens barrel can be removed from the camera body by turning the operation ring to bring the lens barrel into the collapsed state, and further turning the operation ring or the entire lens barrel in the same direction. Therefore, it is not necessary to separately perform the operation of retracting the lens barrel after removing the lens barrel from the camera body, and the lens barrel can be brought into a state of good portability and storage property very naturally. Also, when mounted on the camera body, turning the operation ring in the same direction will enable the lens barrel to take a picture, so there is no need to turn the operation ring in the opposite direction after attaching the lens barrel, so use it The feeling is natural, and there is little risk of missing a photo opportunity due to the operation at this time.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A retractable interchangeable lens barrel according to an embodiment of the present invention will be described below in detail with reference to FIGS. This lens barrel is a zoom lens barrel, and FIGS. 1 and 2 are central sectional views along the optical axis of this zoom lens barrel. FIG. 1 shows a wide (wide-angle) photographing lens.
FIG. 2 shows a state in which the taking lens is in the retracted position.

As shown in the figure, this zoom lens barrel 1
Is a substantially cylindrical fixed barrel 2 and a front group lens moving frame 3 provided inside the fixed barrel 2 and holding the front group lens L1.
A rear-group lens moving frame 4 provided inside the fixed barrel 2 and holding the rear-group lens L2 behind the front-group lens moving frame 3; and a zoom ring (operation ring) provided on the outer periphery of the fixed barrel 2. ) 5 and a cam ring 6 and a linear guide cylinder 7 provided between the fixed barrel 2 and the front group lens moving frame 3 and the rear group lens moving frame 4. A protective glass 3a is attached to the front of the front lens group moving frame 3, and an aperture mechanism 14 (details of the structure are omitted) is provided to the front of the rear lens group moving frame 4.

The zoom ring 5 is rotatable about the optical axis L with respect to the fixed barrel 2 and is attached so as not to move in the optical axis direction. An engagement groove 5a extending in the optical axis direction is formed on the inner surface of the zoom ring 5, and the engagement groove 5a is provided in the cam ring 6 on the camera body 15 (FIG. 5) side (the right side in FIG. 1). A pin 8 implanted on the outer surface of the end of the slidably engages. In addition, on the outer periphery of the zoom ring 5,
A rubber ring 9 for non-slip is mounted.

A male helicoid screw 6a is engraved on the outer surface of the cam ring 6 on the camera body 15 side. Is screwed into. The above-described pin 8 implanted on the outer surface of the end of the cam ring 6 on the camera body 15 side (the right side in FIG. 1) penetrates a relief hole 2b provided in the peripheral wall of the fixed cylinder 2 and its tip is zoomed. It is engaged with the engagement groove 5 a of the ring 5. In the above configuration, when the zoom ring 5 is rotated, the cam ring 6 is rotated via the pin 8, so that the cam ring 6 moves in the optical axis direction by the action of the helicoid screws 6a and 2a.

On the inner surface of the cam ring 6, a front group lens moving frame 3 is provided.
The cam groove 12 with which the front group pin 10 implanted on the outer surface of the end on the camera body 15 side (the right side in FIG. 1) is slidably engaged.
A cam groove 13 is formed on the outer surface of the end of the rear lens moving frame 4 on the subject side (the left side in FIG. 1) so that the rear group pin 11 slidably engages with the rear group pin 11. The cam grooves 12, 1
The shape of No. 3 will be described later.

A guide hole 7a through which the front group pin 10 penetrates and is slidably engaged with the straight guide cylinder 7,
A guide hole 7b through which the rear group pin 11 penetrates and slidably engages with the rear group pin 11 is formed on a straight line along the optical axis (only 7a is shown in FIG. 1). Straight guide cylinder 7
An engaging portion 7c protruding radially outward is formed on the outer surface of the end portion on the camera body 15 side, and the engaging portion 7c is slidably formed on the inner surface of the peripheral wall of the fixed cylinder 2. An engaging groove 2c to be engaged is engraved along the optical axis, and serves as a guide for movement of the straight guide tube. A convex portion 7d extending in the circumferential direction is formed on the outer surface of the rectilinear guide cylinder 7 at a position slightly forward of the engaging portion 7c toward the subject, and the convex portion 7d slides on the inner surface of the cam ring 6. A circumferentially extending engaging groove 6b that movably engages is formed.

FIG. 3 is a view showing the cam grooves 12 and 13, the guide holes 7a and 7b, the front group pin 10, and the rear group pin 11 in a state where the cam ring 6 and the straight guide cylinder 7 are expanded. A portion between the wide (wide-angle) position and the tele (telephoto) position of the cam groove 12 is formed in an arc shape bulging toward the camera body 15 side,
The portion between the wide position and the retracted position is formed in a shape obliquely moving from the wide position toward the camera body 15 side. On the other hand, a portion between the wide position and the tele position of the cam groove 13 is formed in a shape inclined from the wide position toward the subject, and a portion between the wide position and the retracted position is the cam ring 6.
Are formed in parallel with the rotation direction.

When the pins 10 and 11 are in the wide position, the lens barrel 1 is in the state shown in FIG. 1, and the appearance thereof is as shown in FIG. The frame 3 slightly projects. From this state, further rotate the zoom ring 5 (rubber ring 9) to rotate the cam ring 6
Is rotated in the direction of arrow A (FIG. 3), the front group pin 1
0, when the rear group pin 11 moves in the cam grooves 12 and 13 toward the retracted position and reaches the retracted position,
Is in the state shown in FIG. 2, and its appearance is in the state shown in FIG. When the zoom ring 5 is turned in the opposite direction from the wide position to rotate the cam ring 6 in the direction of arrow B,
The front group pin 10 and the rear group pin 11 move inside the cam grooves 12 and 13 toward the tele position, and the cam ring 6 and the front group lens moving frame 3 further protrude. Is in the state shown in FIG. The operation will be described below in detail.

When the zoom ring 5 is turned in the direction of arrow B in FIG. 3 while the pins 10 and 11 are in the wide position, the cam ring 6 also moves toward the object in the optical axis direction while rotating in the direction B. Moves together with the cam ring 6 to the subject side in the optical axis direction without rotating. Therefore, since the cam ring 6 rotates relative to the straight guide cylinder 7, the front group pin 10 and the rear group pin 11 move toward the tele position in the cam grooves 12 and 13. Since the movement of the front group pin 10 is restricted only in the optical axis direction with respect to the rectilinear guide cylinder 7 by the guide hole 7a, the front group pin 10 moves in the optical axis direction with respect to the rectilinear guide cylinder 7. Therefore, the front lens group moving frame 3 and the front lens group L1 also move in the optical axis direction with respect to the straight guide tube 7.

On the other hand, since the movement of the rear group pin 11 is restricted only in the optical axis direction by the guide hole 7b with respect to the rectilinear guide cylinder 7, the rear group pin 11 also moves toward the subject in the optical axis direction with respect to the rectilinear guide cylinder 7. I do. Therefore, the rear lens group moving frame 4 and the rear lens group L2 also move toward the subject in the optical axis direction with respect to the straight guide tube 7. In addition, since the straight guide tube 7 moves toward the subject in the optical axis direction with respect to the fixed tube 2, the front group lens moving frame 3 and the rear group lens moving frame 4 move toward the subject in the optical axis direction with respect to the fixed tube 2. You will travel at different speeds. By moving the front lens group moving frame 3 and the rear lens group moving frame 4 as described above, the overall length of the lens barrel 1 in the optical axis direction becomes longer as the pins 10 and 11 approach the telephoto position. It reaches the longest when it reaches (see FIG. 4A). Also,
By moving the front lens group moving frame 3 and the rear lens group moving frame 4 as described above, the front lens group L1 and the rear lens group L1 are moved.
The relative distance in the optical axis direction between the two changes continuously, and a zooming operation is performed.

Conversely, when the zoom ring 5 is turned in the direction of arrow A in FIG. 3 while the pins 10 and 11 are in the wide position, the cam ring 6 rotates in the same direction A and moves toward the camera body 15 in the optical axis direction. Moving. At this time, the rectilinear guide cylinder 7 does not rotate, but together with the cam ring 6, the optical axis direction camera body 1
Move to side 5. As the cam ring 6 rotates relative to the straight guide cylinder 7, the front group pin 10 and the rear group pin 11
It moves inside the cam grooves 12 and 13 toward the retracted position. Since the movement of the front group pin 10 is restricted only in the optical axis direction by the guide hole 7a with respect to the rectilinear guide cylinder 7, the front group pin 10 moves toward the camera body 15 in the optical axis direction with respect to the rectilinear guide cylinder 7.
Therefore, the front lens group moving frame 3 also moves toward the camera body 15 in the optical axis direction with respect to the straight guide cylinder 7. Further, since the rectilinear guide tube 7 retreats toward the camera body 15 along the optical axis with respect to the fixed tube 2, the front group lens moving frame 3 is fixed to the fixed tube 2.
Is moved toward the camera body 15 in the optical axis direction, and is stored at a position where the front surface is aligned with the fixed cylinder 2.

On the other hand, the rear group pin 11 is restricted by the guide hole 7b and the cam groove 13 from moving backward in the optical axis direction with respect to the rectilinear guide cylinder 7 and does not retreat from the wide position. It does not move relative to it. Therefore, the rear lens group moving frame 4 does not move with respect to the rectilinear guide tube 7. Therefore, the front group lens moving frame 3 and the rear group lens moving frame 4 relatively approach each other.

Front group lens moving frame 3 and rear group lens moving frame 4
Is moved as described above, so that the entire length of the lens barrel 1 in the optical axis direction is the shortest state at the time of shooting, as shown in FIG.
(B) Further shortening from the wide state of FIG.
When the rear group pin 11 reaches 0 and the rear group pin 11 reaches the retracted position, the retracted state is such that the total length in the optical axis direction is the shortest as shown in FIGS.

The camera body 1 of the zoom lens barrel 1
The attachment / detachment method with respect to 5 is a bayonet mount method, which is a standard method of the conventional lens mount mechanism. The lens mount surface is brought into contact with the body side mount surface, and then the lens barrel 1 is turned to mount the lens. To remove it. A lock mechanism for holding the lens barrel 1 in the mounted state is provided on the lens barrel and the camera body 15, and the camera body 15 is provided with a lock release button for releasing this lock. I have.

As shown in FIG. 5, the zoom lens barrel 1 rotates the zoom ring in the retracted state from the photographable state (a state between the telephoto position to the wide position) (retracted direction). And the rotation direction when removing the zoom lens barrel from the camera body 15 is the same, and
The rotation direction (projection direction) of the zoom ring when the zoom lens barrel is changed from the collapsed state to the photographable state and the rotation direction when the zoom lens barrel is attached to the camera body 15 are configured to be the same. I have.

Therefore, in the above configuration, when the zoom lens barrel 1 is detached from the camera body 15, the zoom ring is turned in the direction A as shown in FIG. Figure 6 from possible state
If the lock release button is pressed after the state shown in (b) is collapsed, there is no need to separately perform the operation of removing the lens barrel 1 from the camera body 15 and retracting the lens barrel 1 as a separate operation.
Very naturally, the lens barrel 1 can be brought into a state of good morphology and storage as shown in FIG. In addition, at the time of mounting, the lens barrel 1 in the collapsed state is attached to the camera body 15,
By turning the zoom ring 5 in the same direction (direction B) as it is, the lens barrel 1 becomes ready for photographing, so that there is no need to turn the zoom ring 5 in the opposite direction after attaching the lens barrel 1.
For this reason, the usability at the time of attachment / detachment is natural, and there is little risk of missing a photo opportunity due to the operation at the time of attachment / detachment.

Next, a modification of the above embodiment will be described with reference to FIG.
This will be described with reference to FIG. FIG. 7 is an exploded view of the cam ring 6 and the straight guide cylinder 7 as in FIG.
13, guide holes 7a and 7b, a front group pin 10, and a rear group pin 11 are shown. In this example, the relationship between the tele position and the wide position within the range of the photographable state is reversed from the example of FIG. The cam groove 12 is formed in an arc shape in which a portion between the tele position and the wide position is expanded toward the camera body 15, and a portion between the tele position and the retracted position is skewed from the tele position toward the camera body 15. It is formed in the shape which did. On the other hand, the cam groove 13 has the telephoto position closest to the subject, and the portion between the retracted position and the wide position is formed in a shape obliquely inclined from the telephoto position toward the camera body 15.

Also in this example, as in the case shown in FIGS. 1 to 6, the rotation direction of the zoom ring when changing from the photographable state (the state between the tele position to the wide position) and the collapsed state, and the camera The rotation direction of the zoom ring when removing the zoom lens barrel from the body 15 is the same, and the rotation direction of the zoom ring when the zoom lens barrel is changed from the retracted state to the photographable state, and the camera body 15
The rotation direction of the zoom ring when the zoom lens barrel is attached to the camera is configured to be the same.

In the above configuration, the cam ring 6 is moved to the position A in the figure with the lens barrel attached to the camera body 15.
When turned in the direction, the front group pin 10 and the rear group pin 11 move toward the wide position to the tele position to the retracted position, respectively.
The lens barrel changes from a photographable state to a collapsed state. Therefore, if the lock of the bayonet mount mechanism is released after the lens barrel is in the collapsed state, the collapse operation after removing the lens barrel is unnecessary. On the other hand, when the cam ring 6 is rotated in the direction B while the lens-side mounting surface is aligned with the body-side mounting surface, the front group pin 10
The rear group pin 11 moves from the retracted position to the telephoto position to the wide position, and the lens barrel changes from the retracted state to the photographable state. Therefore, the lens barrel can be brought into a photographable state without any special operation after the lens barrel is mounted.

It goes without saying that the present invention is also applicable to a single focus lens barrel having a retracted state.

[Brief description of the drawings]

FIG. 1 is a central sectional view along an optical axis of a retractable interchangeable zoom lens barrel according to an embodiment of the present invention, showing a wide (wide-angle) state.

FIG. 2 is a central sectional view showing a collapsed state of the zoom lens barrel in FIG. 1;

FIG. 3 is a development view of a cam ring and a straight guide cylinder, showing respective cam grooves, respective guide holes, front group pins, and rear group pins.

FIG. 4A, FIG. 4B, and FIG.
FIG. 4 is a diagram illustrating the appearance of a lens barrel during telephoto, wide, and retracted.

FIG. 5 is a perspective view showing a rotation direction when the lens barrel is operated.

FIG. 6 is a diagram showing an operation of removing a lens barrel.

FIG. 7 is a development view of a cam ring and a straight guide cylinder, showing a modified example of a cam groove and a guide hole.

[Description of Signs] 1 Retractable interchangeable zoom lens barrel 2 Fixed barrel 3 Front group lens moving frame 4 Rear group lens moving frame 5 Zoom ring (operation ring) 6 Cam ring 7 Straight guide cylinder 7a, 7b Guide hole 8 Pin 9 Rubber ring 10 Front group pin 11 Rear group pin 12 Cam groove 13 Cam groove 14 Aperture mechanism 15 Camera body

Claims (1)

[Claims] 1. A structure in which the operation ring (5) is turned so that the entire length in the optical axis direction can be in a collapsed state shorter than the shortest state at the time of photographing, and is detachable from the camera body (15). A retractable interchangeable lens barrel (1), comprising: a rotating direction of an operation ring (5) for changing the lens barrel (1) from a photographable state to a collapsed state; and a lens from the camera body (15). The rotation direction when removing the lens barrel (1) is the same, and the rotation direction of the operation ring (5) when the lens barrel (1) is changed from the retracted state to the photographable state, and the camera body ( A collapsible interchangeable lens barrel characterized in that the rotation direction when the lens barrel (1) is attached to 15) is the same.