JPH0625815B2 - Operation mechanism of zoom lens barrel - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operating mechanism of a zoom lens barrel, more specifically, focusing operation and zooming of a zoom lens barrel mainly used in an autofocus type camera. The operation mechanism of the operation.

[Prior Art] In general, an auto-focus type camera is provided with a motor that drives a photographing lens group arranged in a lens barrel forward and backward in the optical axis direction, and controls the rotation of the motor according to a distance to a subject. Focusing is automatically performed by doing. However, there is a demand to manually perform the focusing operation depending on the usage situation. Therefore, as a solution, a manual operation ring connected to the shooting lens group is installed side by side with the lens barrel, and by rotating the operation ring, the shooting lens group is moved back and forth in the optical axis direction, and focusing is performed manually. I was able to do it. Further, in the case of the zoom lens barrel, a zooming operation ring for performing zooming operation is provided separately from this, and zooming is performed by the zooming operation ring.

[Problems to be Solved by the Invention] In the above-described conventional apparatus, the manual operation ring for focusing is always connected to the taking lens, so that when the auto focus is activated, the manual operation ring for focusing also rotates. Therefore, if the operating ring is touched by a hand at this time, a large load is applied to the motor, the connecting member in the middle, and the like, which causes a malfunction due to a failure.
Therefore, in many cases, the manual operation ring for focusing is
The hand is arranged in a portion where it is difficult to contact carelessly, and conversely, there is a drawback that it is extremely difficult to operate during manual operation.

Also, in the case of an interchangeable lens with a long lens barrel such as a zoom lens that covers the telephoto range, a member that covers the manual operation ring for focusing is provided to prevent the hand from accidentally touching the operation ring. is there. But for something like this,
It is longer than an operating ring that requires a certain length in terms of operability during manual operation, and a large member must be installed separately to cover the manual operating ring, making the device larger and handheld shooting possible. There is a drawback that it becomes difficult, and since a large operating ring for manual operation is driven by the motor during the operation of autofocus, there is a drawback that a large load is applied to the motor and the life of the motor and the battery is significantly reduced. It was

The present invention provides a zoom lens barrel operating mechanism that solves the above-mentioned conventional drawbacks, has good manual focusing operability, and does not apply a large load to a motor or the like during the operation of autofocus. With the goal.

[Means for solving problems]

In order to solve the above problems, an operation mechanism of a zoom lens barrel according to the present invention includes a zoom mechanism for moving a zoom lens group forward and backward in an optical axis direction, and a focus mechanism for moving a focus lens group forward and backward in the optical axis direction. In an operating mechanism of a zoom lens barrel, a mechanism and an operating ring for selectively engaging with one of the zoom mechanism and the focus mechanism to advance and retract one of the zoom lens group and the focus lens group are provided. , The zoom mechanism and the focus mechanism are provided with a plurality of comb-teeth-shaped grooves extending parallel to the operation ring in a ring shape around the optical axis, and the operation ring is moved in the optical axis direction on the operation ring. By this, a spherical member that is engaged with and disengages from the groove and engages with the groove on either side of the zoom mechanism and the focus mechanism is provided, and thereby the rotational movement of the operation ring around the optical axis is provided. The is characterized in that so as to selectively transmit to the zoom mechanism and the focus mechanism.

[Operation] When the operating ring is engaged with the focus mechanism, focusing is performed by operating the operating ring. When the operation ring is switched and engaged with the zoom mechanism, zooming is performed. At this time, since the operation ring and the focus mechanism are not engaged, even if the focus mechanism is driven by the autofocus motor, the operation ring is The movement cannot be transmitted to.

[Embodiment] FIG. 1 is a cross-sectional view of an embodiment of the present invention, and the illustration of the lower half is omitted.

In the figure, 1 is an inner body of the lens barrel, 2 is an outer body fixed to the outer side thereof, and a front cover 3 and a rear cover 4 are fixed to the outermost surface thereof. 5 is a bayonet claw that engages with the mount of the camera body fixed to the rear end of the lens barrel,
Reference numeral 6 denotes an aperture ring that adjusts the aperture area of an aperture stop (not shown).

Fixed lens groups 7 and 8 are fixed to the front end and the rear side of the inner body 1. Along the way, a zoom lens group 9 composed of a front group 9a and a rear group 9b, and a focus lens group 10 are fixed to lens frames 11a, 11b, 12 which are arranged to be movable back and forth in the optical axis direction. ing. Each of the lens frames 11a, 11b, 12 has a pin 13
a, 13b, and 14 are provided in a protruding manner, and the pins penetrate through the long holes 15a, 15b, 16 formed in the inner body 1 in the optical axis direction. A zooming cam cylinder 17 and a focusing cam cylinder 18 are rotatably fitted to the outer periphery of the inner body 1, and the cams 19a, 19b and 20 formed on the cam cylinders 17 and 18 have the above-mentioned pins. 13a,
13b and 14 are engaged with each other. Therefore, when the zoom cam cylinder 17 rotates, the zoom lens groups 9a and 9b move back and forth in the optical axis direction to perform zooming.
When the focusing cam barrel 18 rotates, the focus lens group 10 moves back and forth in the optical axis direction for focusing.

A zoom operation cylinder 21 and a focus operation cylinder 22 are rotatably arranged on the outer periphery of the outer main body 2. A head of a screw 24 standing on the zooming cam barrel 17 engages with a groove 23 formed on the inner surface of the zooming barrel 21, and the zooming cam barrel 17 and the zooming cam are actuated via the screw 24. The cylinder 21 rotates integrally. Reference numeral 25 denotes a groove formed in the outer main body 2 in the circumferential direction, and the screw 24 penetrates through the groove. The focus operating barrel 22 is integrally connected to the focusing cam barrel 18 via a coupling barrel 40 by a screw (not shown), and the focus operating barrel 22 and the focusing cam barrel 18 rotate integrally. In this way, the zoom cam barrel 17 and the zoom actuating barrel 21
The zoom mechanism is configured by the above, and the focusing mechanism is configured by the focusing cam barrel 18 and the focus operating barrel 22. Further, an internal gear 26 is formed on the inner peripheral side of the focus operating cylinder 22, and a gear (not shown) driven by an autofocus motor.
Engages with the internal gear 26, and the focus operating cylinder 22
Is driven to rotate by an autofocus motor.

An operation ring 27 is rotatably attached to the outer periphery of the central portion of the outer body 2. The operation ring 27 is also arranged so as to be able to move back and forth in the optical axis direction. In the vicinity of the center of the lower surface of the operation ring 27, a pair of V-shaped parallel grooves 28 are formed in the circumferential direction, and a click ball 30 pressed by a coil spring 29 from the outer main body 2 side is arranged. The operation ring 27 is engaged with either one of the parallel grooves 28, and the operating ring 27 is clicked at any position to determine the axial position. FIG. 1 shows a state in which the operating ring 27 is on the tip side (left side in the figure), and FIG. 3 shows a state in which the operating ring 27 is on the rear side (right side in the figure).

Holes 31 and 32 are formed near the left and right ends of the operation ring 27, and steel balls 33 and 34 are fitted into the holes 31 and 32. The steel balls 33, 34 are equally divided in the circumference and are arranged on the left and right sides of the operation ring 27, for example, six each, and are pushed inward by a ring-shaped leaf spring 35 provided on the outside thereof.

The focus actuating cylinder 22 has a large number of grooves 36, which are engaged with the steel balls 33 when the operating ring 27 is on the left side as shown in FIG. FIG. 2 shows a state in which the steel ball 33 is engaged with the groove 36. Since the groove 36 is continuously formed on the circumference, the operation ring 27 is rotated to be in any position. Even, steel ball 33
And the groove 36 can engage. Further, the zoom actuating cylinder 21 is also formed with a groove 37 exactly the same so that the steel ball 34 is engaged when the operation ring 27 is on the rear side (right side) as shown in FIG. Has become.

Reference numerals 38 and 39 denote the front cover 3 and the rear cover so that the distance scale displayed on the outer periphery of the focus operating cylinder 22 or the zoom scale displayed on the outer periphery of the zoom operating cylinder 21 can be seen from the outside. 4 is a transparent window.

In the operation mechanism of the zoom lens barrel of the present embodiment configured as described above, in the state of FIG. 1 in which the operation ring 27 is set to the front side (left side in the drawing), the operation ring 27 has the steel ball 33 and the groove 36. It engages with the focus operating cylinder 22 via. Therefore, by rotating the operation ring 27, the focus lens group 10 moves back and forth in the optical axis direction, and manual focusing can be performed. At this time, the operation ring 27
Since the zoom operating cylinder 21 is separated from the zoom operating cylinder 21, the zoom mechanism does not operate.

When the operating ring 27 is moved backward (to the right in the figure) as shown in FIG. 3, the steel ball 34 engages with the groove 37 of the zoom operating cylinder 21, so that the operating ring 27 should be rotated. As a result, the zoom lens groups 9a and 9b move back and forth in the optical axis direction, and zooming is performed. At this time, since the operation ring 27 and the focus operating cylinder 22 are separated from each other, even if the focus mechanism is operated by the motor for autofocusing, the movement is not transmitted to the operation ring 27.

[Effect of the Invention] According to the operation mechanism of the zoom lens barrel of the present invention, since the operation ring that selectively engages with either the focus mechanism or the zoom mechanism is provided, the operation ring engages with the focus mechanism. If so, focusing can be performed manually. Then, when the operation ring is engaged with the zoom mechanism, the operation ring and the focus mechanism are separated from each other, so that even if the autofocus is activated, the movement is not transmitted to the operation ring and a large load is not applied to the motor. Further, since the operation ring does not rotate during autofocus, it is possible to arrange the operation ring at a position most convenient for an operation that is easy to touch. In addition, since the rotational movement of the operating ring around the optical axis is selectively transmitted to the zoom mechanism and the focus mechanism by engaging and disengaging the comb-shaped groove and the spherical member, the zoom mechanism and the focus mechanism can be operated. Regardless of the state of the ring, you can smoothly switch the operating ring from one that engages the zoom mechanism and the focus mechanism to the other that engages the zoom mechanism and the focus mechanism. It can be realized by a mechanism.

[Brief description of drawings]

FIG. 1 is a side sectional view of a lower half portion of an embodiment of the present invention in which illustration is omitted, FIG. 2 is an enlarged plan view of a steel ball and a groove portion thereof, and FIG. 3 is a state in which an operating ring is moved. FIG. 1 ... Inner body, 2 ... Outer body, 9a, 9b ... Zoom lens group, 10 ... Focus lens group, 13a, 1
3b ... Pin, 14 ... Pin, 17 ... Zooming cam barrel, 18 ... Focusing cam barrel, 19a, 19
b ... Cam, 20 ... Cam, 21 ... Zoom actuating cylinder, 2
2 ... Focus operating cylinder, 23 ... Groove, 24 ... Screw,
27 ... Operation ring, 28 ... Parallel groove, 29 ... Coil spring, 30 ... Click ball, 31, 32 ... Hole, 3
3, 34 ... Steel balls, 35 ... Leaf springs, 36, 37 ...
groove.

Claims (1)

[Claims] 1. A zoom mechanism for moving a zoom lens group forward and backward in the optical axis direction, a focus mechanism for moving a focus lens group forward and backward in the optical axis direction, and either one of the zoom mechanism and the focus mechanism, selective. An operation ring for moving one of the zoom lens group and the focus lens group forward and backward by engaging with the zoom lens group. A plurality of comb-teeth-shaped grooves extending in parallel are provided in an annular shape around the optical axis, and the operating ring is disengaged from the groove by moving the operating ring in the optical axis direction. A spherical member that engages with the groove on either side is provided so that the rotational movement of the operating ring around the optical axis is selectively transmitted to the zoom mechanism and the focus mechanism. An operating mechanism for a zoom lens barrel, which is characterized in that