JPH10153731A - Lens barrel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a lens barrel unnecessitating switching operation between manual and automatic operation and capable of rapidly adjusting the condition with respect to a subject. SOLUTION: An input gear 23, a sun gear 26, a planet gear 27 and a crown gear 30 having an external tooth 30A are provided as a planet gear mechanism, and an output gear 29 is attached to a shaft 24. The external tooth 19A of a manually operated focusing ring 19 is meshed with the external tooth 30A of the gear 30, and the gear 21 of a motor 20 is meshed with the gear 23, so that each rotation is separately transmitted to the gear 29. By the rotation of the gear 29, a focusing lens 17 is driven in an optical axis direction through a driving ring 32. The index 35 for focusing operation is put on the outer surface of the ring 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel capable of performing both a manual focusing operation and an automatic focusing operation in a lens portion of a camera.

[0002]

2. Description of the Related Art Cameras, television cameras and the like are provided with a focus lens for focusing and a zoom lens for zooming. In particular, in the operation of driving the focus lens, switching between manual and automatic (electrically driven) is performed. There are things that can be done.

FIGS. 5 and 6 show a manual operation and an electric (automatic) operation.
1 shows a configuration of a conventional camera lens barrel that can be switched to a focusing lens 2 inside a lens barrel 1 shown in FIG.
Is held by the holding frame 3. A manual focus (operation) ring 4 and a connection ring 5 are provided outside the lens barrel 1, and a clutch portion 6 formed by coupling teeth 4 </ b> A and 5 </ b> A is formed at a contact portion between the two members.

Although not shown, an extension 3A of the holding frame 3 is engaged with the linear groove of the connecting ring 5 by a key structure so as to be movable back and forth. The body 1 is connected to the torso 1 by a helicoid H, and the focus lens 2 moves back and forth as the connection ring 5 rotates. External teeth 7 are formed on the outer periphery of the connection ring 5 and an index (distance scale) 8 of a focus operation is provided.

[0005] Further, a motor 9 and a gear 10 for electric driving are arranged, and a switching gear 11 which can mesh with the gear 10 and meshes with the external teeth 7 of the connecting ring 5 is provided. The switching gear 11 has a disk-shaped engaging member 12 that engages with the focus ring 4, and slides along the axis 13 by operating the focus ring 4 in the optical axis direction. .

According to the above configuration, at the time of manual operation, as shown in FIG. 5, the focus ring 4 is moved rearward (to the right in the figure) to release the meshing between the switching gear 11 and the gear 10, and The part 6 is engaged. After that, when the focus ring 4 is rotated, the connection ring 5
In addition, the focus lens 2 can be moved in the optical axis direction through the helicoid coupling of the holding frame 3, thereby enabling focusing.

On the other hand, when auto focus is set, FIG.
As shown in (2), the focus ring 4 is moved forward, the switching gear 11 is engaged with the gear 10, and the engagement of the clutch portions 6 (4A, 5A) is released. Then, the rotation of the motor 9 is transmitted to the connection ring 5 by the meshing of the gear 10 and the switching gear 11, and the autofocus that moves the focus lens 2 in the optical axis direction through the connection of the connection ring 5 and the extension 3 </ b> A. Operation becomes possible.

[0008]

By the way, in the conventional camera lens driving device capable of performing both the manual operation and the automatic operation as described above, the switching gear 11 is connected to the focus ring 4.
However, if the switching operation is not required, a convenient camera device with simplified operation can be provided. In addition, since the above-described switching operation is required, it may not be possible to quickly adjust conditions such as focusing on a subject, and in this case, there is a disadvantage that a photo opportunity is missed.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a lens barrel which does not require a manual or automatic switching operation, and which can quickly adjust conditions for a subject. Is to do.

[0010]

According to a first aspect of the present invention, there is provided a lens barrel for holding a movable lens so as to be movable in an optical axis direction. A manual operation ring for manual operation for moving the lens in the optical axis direction, a motor-side gear connected to the electric motor, and a rotatable outer periphery of the lens barrel. The drive ring for moving the lens in the optical axis direction, the manual operation ring and the motor-side gear are connected to respective input gears, and the rotation of the manual operation ring and the motor-side gear is adjusted. A planetary gear mechanism for separately transmitting the output gear to the output gear, wherein the rotation of the output gear of the planetary gear mechanism is transmitted to the drive ring. The invention according to a second aspect is characterized in that an index of an operation state of the lens is provided on an outer surface of the drive ring. The invention according to a third aspect is characterized in that the output gear of the planetary gear mechanism is provided with an adjusting gear for adjusting the rotation amount of the drive ring to be equal to the rotation amount of the manually operated ring.

According to the above configuration, for example, in a focus operation, a manual operation and an automatic operation can be performed without using a switching gear or the like. That is, when the manual operation ring is rotated, the motor side acts as a load, the motor side gear is fixed, and the drive ring rotates via the planetary gear mechanism. The rotation of the drive ring moves the lens in the optical axis direction.

On the other hand, when the electric motor is driven, the operation ring side member serves as a load to fix the operation ring, and the drive ring is rotated via the planetary gear mechanism. Thus, the lens is moved in the optical axis direction in the same manner as described above. As described above, by using the planetary gear mechanism, a manual operation and an automatic switching operation can be eliminated.

[0013] According to the third aspect of the present invention, by using the adjusting gear, the rotation amount of the driving ring and the manual operation ring can be made equal, and the operation feeling can be matched with the conventional operation feeling. It becomes possible.

[0014]

1 to 3 show the configuration of a lens barrel according to an embodiment. FIG. 1 is an enlarged view of a part of the upper part of FIG. As shown in FIG. 2, a lens group for focusing and zooming is arranged in a lens barrel 16 to which the hood 15 is attached.
In particular, the focus lens 17 is movably mounted together with the holding frame 18 for focusing. A manually operated focus ring 19 is rotatably mounted on the outer periphery of the lens barrel 16. A motor 20 for autofocus is provided at a distance from the lens barrel 16 by supporting means (not shown), and a gear 21 is mounted on the shaft of the motor 20.

A planetary gear mechanism is connected to the gear 21 and the focus ring 19. That is, as shown in detail in FIG.
Is rotatably mounted on a shaft 24. Further, a sun gear 26 is provided so as to be integrated with the input gear 23, and the sun gear 26
, Three (arbitrary numbers) planetary gears 2
7 are arranged so as to mesh with each other. This planetary gear 27
The arm 28 is supported by an arm 28, and the arm 28 is fixed to a shaft 24. The shaft 24 has an output gear 2 shown on the right side of FIG.
9 are fixedly arranged. Therefore, the arm 28 and the output gear 29 rotate integrally.

Further, a crown gear 30 having internal teeth meshing with the planetary gear 27 is rotatably provided on the shaft 24. On the outer periphery of the crown gear 30, external teeth 30A as input gears are formed. The pitch circle diameter and the number of teeth of the external teeth 30A are the same as the pitch circle diameter and the number of teeth of the output gear 29. On the other hand, the focus ring 19 also has external teeth 19A formed thereon, and the external teeth 19A are arranged so that the external teeth 30A of the crown gear 30 mesh with the external teeth 19A.

Therefore, the rotation of the focus ring 19
Assuming that the input gear 23 on the motor 20 side is in a fixed state, the rotation of the planetary gear 27 and the arm 28 causes the output gear 2 to rotate.
9 is transmitted. On the other hand, the rotation of the gear 21 of the motor 20 is transmitted to the output gear 29 by the rotation of the planetary gear 27 and the arm 28, assuming that the crown gear 30 connected to the focus ring 19 is in a fixed state.

A drive ring 32 is rotatably provided on the outer periphery of the lens barrel 16, and the output gear 29 is arranged so as to mesh with external teeth 32A formed on the drive ring 32. A linear groove is formed in the front extension 33 of the drive ring 32, and the extension 34 of the holding frame 18 of the focus lens 17 is coupled to the linear groove so as to move only in the front-rear direction. Well-known key structure).
A helicoid H is provided between the holding frame 18 and the lens barrel 16.
The focus lens 17 is moved linearly in the optical axis direction by the rotation of the drive ring 32.

Further, in the embodiment, the driving ring 3
As shown in FIG. 2, an index (numerical) 35 indicating the operating state of the focus (lens 17) is attached to the outer peripheral surface of No. 2.

The embodiment has the above configuration, and its operation will be described below. Manual focus ring 1 in FIG.
9, the external teeth 19A and the external teeth 30
The engagement of A causes the crown gear 30 to rotate. Then, the motor 20, the gear 21, and the input gear 23 serve as a load, and the sun gear 26 is fixed, and FIG.
As shown in (A), the engagement between the planetary gear 27 and the internal teeth of the crown gear 30 causes the arm 28 to rotate counterclockwise with the shaft 24. The rotation of the arm 28 is output as the rotation of the output gear 29 in FIG.

As described above, when the output gear 29 of FIG. 1 rotates, the drive ring 32 is rotated by the engagement between the output gear 29 and the external teeth 32A. This drive ring 32
Is converted into a linear motion by the coupling of the extension portions 33 and 34 and the coupling of the helicoid H between the lens barrel 16 and the holding frame 18, and the focus lens 17 is moved in the optical axis direction by a predetermined amount. This enables focusing.

In the above, one of the focus rings 19
The amount of rotation of the drive ring 32 with respect to the rotation can be grasped as follows based on the relationship between the number of rotations of the crown gear 30 and the output gear 29 (arm 28). That is, the number of teeth (or pitch circle diameter) of the sun gear 26 is S1, the number of teeth of the crown gear 30 is S2, and the rotation speed C of the arm 28 when the sun gear 26 is fixed is C = S2 / ( S1 + S2). here,
Although slightly different from the figure, S1: S
Assuming that 2 = 1: 2, C = ２, and when the focus ring 19 is rotated once, the drive ring 32 rotates ／.

On the other hand, during the autofocus operation, the motor 20 is driven to rotate, and this rotation is
1 to the input gear 23 integrated with the sun gear 26. Then, the focus ring 19 functions as a load, and the crown gear 30 is fixed, and FIG.
As shown in (B), the engagement of the internal teeth of the crown gear 30 and the planetary gear 27 causes the arm 28 to rotate counterclockwise together with the shaft 24, and the rotation of the arm 28 causes the output of FIG. It is output as the rotation of the gear 29.

Also in this case, the drive ring 32 is rotated by the output gear 29, and the drive of the drive ring 32 moves the focus lens 17 by a predetermined amount in the optical axis direction, thereby enabling focusing. .

The amount of rotation of the drive ring 32 per one rotation of the input gear 23 during such autofocusing can be grasped as follows. That is, when the number of teeth of the sun gear 26 is S1, the number of teeth of the crown gear 30 is S2, and the crown gear 30 is fixed, the rotation number C of the arm 28 is C = S1 //
(S1 + S2), and S1: S2 =
If 1: 2, C = 1/3, and when the focus ring 19 is rotated once, the drive ring 32
Make three rotations. Therefore, the rotational drive amount of the motor 20 in this example may be determined in consideration of such a rotational ratio.

In such a focus operation, since the focus index 35 is provided on the outer peripheral surface of the drive ring 32, the state of the focus operation can be confirmed by the index 35.

FIG. 4 shows an example in which an adjustment gear for adjusting the amount of transmission of the rotation operation amount is provided. As shown in FIG.
An adjusting gear 36 having two gears having different numbers of teeth and an adjusting gear 37 for changing the rotation direction are arranged. According to this, the amount of transmission from the output gear 29 to the drive ring 32 can be adjusted by the gear ratio of the adjustment gear 36.

For example, in the example of FIG. 1, as described above, the rotation ratio of the focus ring 19 and the drive ring 32 is 1: (2
/ 3), the amount of rotation is adjusted to (3 /
2) If the number of rotations is increased twice, the rotation ratio between the two can be made 1: 1. According to this, the focus ring 1
The movement amount of the focus lens 17 based on the operation amount of No. 9 becomes the same as the conventional one, and there is an advantage that the focus operation can be performed with the same feeling as the conventional one.

Further, in the above-described embodiment, the drive structure of the focus lens 17 has been described. However, the above-described structure of the present invention can be similarly applied to a zoom lens or the like.

[0030]

As described above, according to the first aspect of the present invention, the planetary gear which inputs the rotation of the manually operated ring and the rotation of the motor side gear and transmits each rotation to the output gear separately. A mechanism for transmitting the rotation of the output gear of the planetary gear mechanism to the drive ring for driving the lens eliminates the need for manual and automatic switching operations, and allows quick adjustment of conditions for the subject. There are advantages.

According to the second aspect of the present invention, since an index of the operating state is given to the driving ring, the operating state of the lens can be confirmed.

According to the third aspect of the present invention, an adjusting gear for adjusting the amount of rotation is provided between the output gear of the planetary gear mechanism and the drive ring. The amount of rotation can be made the same, and it becomes possible to match the conventional operation feeling.

[Brief description of the drawings]

FIG. 1 is an overall view showing a configuration of a lens barrel (lens unit) according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing a part of the upper side of FIG.

FIG. 3 shows an operation state of the planetary gear mechanism of FIG. 1, and FIG. 3 (A) is a view when a focus ring is manually operated;
FIG. 7B is a diagram at the time of auto focus.

FIG. 4 is a cross-sectional view showing a configuration in which an adjustment gear is provided in the device of FIG.

FIG. 5 is an overall view showing a configuration of a conventional camera lens driving device (lens unit).

FIG. 6 is an enlarged sectional view showing a part of the upper side of FIG. 5;

[Explanation of symbols]

 1,16 ... lens barrel, 2,17 ... focus lens, 4,19 ... focus ring, 9,20 ... motor, 23 ... input gear, 26 ... sun gear, 27 ... planetary gear, 28 ... arm, 29 ... output Gear, 30 ... Crown gear, 32 ... Drive ring, 35 ... Index.

──────────────────────────────────────────────────続 き Continued on front page (51) Int.Cl. ⁶ Identification code FI G03B 13/34

Claims (3)

[Claims] 1. A lens barrel for holding a movable lens so as to be movable in an optical axis direction, and a manual for manual operation for rotating the lens in the optical axis direction, the lens being rotatably disposed on an outer peripheral portion of the lens barrel. An operation ring, a motor-side gear connected to the electric motor, a drive ring that is rotatably arranged on the outer peripheral portion of the lens barrel, and moves the lens in the optical axis direction, A motor-side gear connected to each of the input gears, and a planetary gear mechanism for separately transmitting rotations of the manual operation ring and the motor-side gear to an output gear, wherein the output gear of the planetary gear mechanism is rotated. A lens barrel configured to transmit to the drive ring. 2. The lens barrel according to claim 1, wherein an index of an operation state of the lens is provided on an outer surface of the drive ring. 3. The first or second output gear of the planetary gear mechanism is provided with an adjusting gear for adjusting a rotation amount of the drive ring to be equal to a rotation amount of a manually operated ring. The lens barrel according to claim 2.