JPH0792365A - Lens barrel - Google Patents

Abstract

PURPOSE:To improve the operability by consecutively taking the moving action of an optical member by operation of a manually operating member, continuous from the moving action by a driving means. CONSTITUTION:When a photographer operates a focusing switch to try to drive a focusing lens group 2 by an automatic focusing action (the drive of a motor), a first pulley 14 is rotated. Then, a moving lens barrel 9 is moved in a optical axial direction because a movable wire-like body 10 is wound on the first pulley 14 one turn. On the other hand, when the photographer turns a focusing ring 4 to try to move the focusing lens group 2 by a manual focusing action, the turning is transmitted to an internal tooth part 4a, a first gear 22a, a worm gear 22b and a second gear 13, to rotate a second pulley 12. Thus, the movable wire-like body 10 is turned between the second pulley 12 and a winding part 11. Therefore, the first pulley 14 is not rotated but the moving lens barrel 9 is moved in the optical axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens barrel for moving an optical member by at least operating a manually operated member.

[0002]

2. Description of the Related Art In a known autofocus camera configured to selectively perform an autofocus operation and a manual focus operation, a switch from the autofocus operation to the manual focus operation or a change from the manual focus operation to the autofocus operation is performed. When the camera user (photographer) intends to perform the switching operation of (1), it is necessary to operate the switching operation member provided outside the camera or outside the lens barrel.

Further, the applicant of the present invention has disclosed a lens barrel capable of almost continuously performing an automatic focusing operation and a manual focusing operation without requiring a switching operation.
-253210 and JP-A-2-253214.

In recent years, even when a lens barrel for driving a zoom operation by a motor is commercialized, a function called auto-zoom (automatically changing a zoom ratio according to a change in subject distance) attracts attention. ing.

[0005]

However, in the known camera described above, when attempting the manual focus operation after the auto focus operation, the photographer rotates the focus ring of the lens barrel of the camera after operating the switching operation member. Since the operation has to be performed, the operability is bothersome, but the start of the manual focus operation is delayed, and as a result, there is a risk of missing a shooting opportunity.

Further, JP-A-2-253210 and JP-A-2-25310.
In 253214, since the application of the planetary gear mechanism requires that the autofocus side be kept as it is during the manual focus operation, the self-holding force (force for maintaining the current position of the drive shaft) such as a vibration wave motor is maintained. There is a problem that it will not work well unless it is a strong motor, or it is necessary to separately provide a pressing means for obtaining a holding force.

On the other hand, in a lens barrel having a structure in which an optical member is extended by a rotary ring member such as a cam ring, it is more accurate to reverse the rotation direction of the manual operation member such as the focus ring and the cam ring in view of the design of the cam groove. However, in this case, an annular member must be additionally provided on the outer circumference of the cam ring, which causes a problem that the outer shape of the lens barrel becomes large.

[0008]

In view of the above points, according to the present invention, in a lens barrel for moving an optical member by operating a manually operated member and driving a drive source, a flexible linear member and the flexible wire are provided. A first rotatable member that is wound around the optical member at least once, and a position where the flexible linear member is wound around and sandwiches the first rotatable member. A second rotatable member and a winding portion, a driving means for driving the first rotatable member, and an operating force of the manually operated member to the second rotatable member. By providing the transmitting means for transmitting, the moving operation of the optical member by the driving means and the subsequent moving operation of the optical member by the operation of the manual operation member can be continuously performed.

Further, a rotatable member which is interlocked with the operation of the flexible linear member and the manual operation member, and which is rotatable around which the flexible linear member is wound, and a winding member around which the flexible linear member is wound. A rotary ring member that has a portion and that moves the optical member by rotating around the optical axis integrally with the winding portion by the transmission force of the flexible linear member and a rotary ring member and a manual It is also easy to reverse the moving direction of the operating member.

[0010]

1 is a sectional view of a first embodiment of a lens barrel according to the present invention, which is a single-focus / rear-focus lens barrel. Reference numeral 1 denotes a fixed first lens group, which is held by a lens holding barrel 3. Reference numerals 2 and 9 denote movable optical members, 2 denotes a focusing lens group, and a movable lens barrel 9
The focus position can be changed by moving the movable lens barrel 9 in the optical axis direction. A motor as a drive unit and a drive unit 21 for its speed reduction mechanism are fixed to the movable lens barrel 9, and a brush 20 for detecting the lens position is also fixed. Drive unit 2
A first rotatable member (hereinafter referred to as a pulley) 14 is attached to the output shaft 1. The brush 20 has a contact portion provided at a position away from the cutout portion of the fixed cylinder, and the encoder 19 detects the position of the lens. The supply voltage to the motor is provided by a U-turn flexible substrate (not shown).

Reference numeral 6 designates the lens barrel of the camera body (not shown).
Is a mount for connecting to the camera body, and can communicate with the camera body by the electric contact portion 8. 5 and 1
Reference numeral 7 is a fixed barrel, 5 is a fixed barrel fixed to the mount, and is fixed together with the second fixed barrel 17 to which the lens holding barrel 3 is fixed, without the operation of the photographer. The fixed barrel 5 is provided with a cutout 5a so that a part of the movable barrel 9 and the drive unit 21 can be projected to the outer peripheral side from the fixed barrel, and a guide groove 5b so that the movable barrel 9 can be moved in the optical axis direction. ing. Reference numeral 7 denotes an electric mounting board, on which elements such as a control microcomputer 7a in the lens barrel are arranged, and an electric contact portion 8, a flexible board (not shown) connected to a motor, a flexible board 7b for an encoder, etc. are connected. Has been done.

A peripheral groove portion 4b is formed in the focus ring 4 as a manual operation member, and Corobis 17a arranged at three places on the outer peripheral portion of 17 slide in the peripheral groove portion 4b. Therefore, the focus ring 4 can rotate endlessly at a fixed position. It should be noted that the focus ring 4 has a hole 4 for incorporating the Corobis 17a.
c is formed. Further, the focus ring 4 is formed with an internal tooth portion 4a, and 4a meshes with a first gear 22a whose shaft is held by a fixed barrel. First gear 22
A worm gear 22b is formed coaxially with a so as to mesh with the second gear 13. That is, the inner tooth portion 4a, the first gear 22a, the worm gear 22b, and the second gear 13 are transmission means for transmitting the operation of the manual operation member to the second rotatable member, and the focus ring 4
The second gear 13 is rotated by the operation. The second rotatable member (pulley) 12 is configured coaxially with the second gear 13, and the shaft thereof is held by the fixed barrel 5. The second pulley 12 is a flexible linear member 10 and the first pulley 1
4 and the winding portion 11 of the fixed cylinder.

Further, in this embodiment, the winding portion 11 of the fixed barrel is held by the movable member 16 which is movable, and 16 is moved by the groove portion 17b provided in the second fixed barrel 17 in a direction other than the optical axis direction. Is regulated and the biasing member 1
5 urges the flexible linear body 10 in a direction to increase the tension thereof. In addition, the flexible linear member 10 is wound around the first pulley 14 once, and the second pulley 12
It is also connected to the winding portion 11.

Next, the operation of the lens barrel of this embodiment having the above structure will be described. When the photographer wants to drive the focusing lens group 2 by an autofocus operation (motor drive), he operates a focusing switch (not shown). Then, a voltage is supplied to the motor according to the operation of a control circuit (not shown), and as a result, the output shaft of the drive unit 21 rotates, so that the first pulley 14 is rotated.
Rotates. Since the flexible linear member 10 is wound around the first pulley 14 once, the movable lens barrel 9 moves in the direction A or B, which is the optical axis direction, depending on the rotation direction.

Here, the urging member 15 is urged in a direction to apply tension so that the first pulley 14 does not idle, and the drive unit is transmitted to the first pulley 14 by the flexible linear member 10. The relationship between the driving force F _{1 of} 21 and the rotational operation force F ₂ of the focus ring 4 transmitted to the second pulley 12 by the flexible linear member 10 is set so that F ₁ > F _2. There is.

The value of F ₁ can be adjusted by the position of the Corobis 17a, the lubricating oil applied between the focus ring 4 and the fixed barrels 5, 17, and the like.

As described above, the movable lens barrel 9 can be moved in the optical axis direction by the autofocus operation.

On the other hand, the photographer sets the focusing lens group 2
When moving the focus ring 4 by manual focus operation, rotate the focus ring 4
A, the first gear 22a, the worm gear 22b, and the second gear 13 are transmitted to rotate the second pulley 12. As a result, the flexible linear member 10 rotates between the second pulley 12 and the winding portion 11.

Further, the first pulley 14 and the flexible linear member 1
The relationship between the frictional force F _{3 of} 0 and the driving force F ₁ of the driving unit 21 transmitted to the first pulley 14 by the flexible linear member 10 is F ₃ > It is set to be F ₁ .

Therefore, the movable lens barrel 9 moves in the optical axis direction without rotating the first pulley 14. It should be noted that, in both the autofocus operation and the manual focus operation, the first
The stopper receiving portion 9 provided in the movable lens barrel 9 so that the pulley 14 and the second pulley 12 may not collide with each other.
The a and 9b contact the stopper portions 17c and 5c of the fixed cylinder, and the movement range is restricted. If the focus ring 4 may be further rotated after the movable lens barrel 9 is moved to the infinite end or the closest end, the wrapping portion 11 of the moving member 16 is moved to the urging member 15. On the contrary, it slightly moves to the mount side, the tension of the flexible linear member 10 decreases, and the frictional force F ₄ between the second pulley 12 and the flexible linear member 10 at this time and the flexible linear member 10 Drive unit 21 transmitted to the first pulley 14 by
Driving force F ₁ of the focus ring 4 transmitted to the second pulley 12 by the flexible linear member 10
The relationship with ₂ is: F ₁ > F ₄ > F ₂ , and the second pulley 12 spins idle to prevent breakage.

FIG. 2 is a sectional view of the second embodiment, which shows a single-focus / rear-focus lens barrel. FIG. 3 is an A-A view.

Reference numeral 51 denotes a fixed first lens group, which is held by a lens holding barrel 53. Reference numerals 52 and 59 denote movable optical members. Reference numeral 52 denotes a focusing lens group, which is held by the movable lens barrel 59, and the fixed barrel 5 is attached to the movable lens barrel 59.
5 of the guide groove 55a and a cam ring 60 as a rotary ring member.
A roller 59a penetrating the cam groove 60a is provided, and when the cam ring 60 rotates, the movable lens barrel 59 moves in the optical axis direction and the focal position can be changed. The cam ring 60 is designed to rotate at a fixed position.

Reference numeral 61 denotes a drive unit fixed to the cam ring 60, which is a drive unit for a motor and a speed reduction mechanism for the motor, and a voltage is supplied by a U-turn flexible substrate (not shown) in the rotating direction. A first rotatable member (hereinafter referred to as a pulley) 71 is attached to the output shaft of the drive unit 61.

Reference numeral 56 denotes a mount for connecting the present lens barrel to a camera body (not shown), and an electric contact portion 58.
Allows you to communicate with the camera body. 5
Reference numeral 5 denotes a fixed barrel fixed to the mount, and is fixed together with the second fixed barrel 62 to which the lens holding lens barrel 53 is fixed, without the operation of the photographer. A guide groove 55a is formed in the fixed cylinder 55. Reference numeral 57 denotes an electric mounting board, on which elements such as a control microcomputer 57a in the lens barrel are arranged, and an electric contact portion 58, a flexible board (not shown) connected to a motor, and the like are connected.

A peripheral groove portion 54b is formed in the focus ring 54 as a manual operation member, and the Corobis 62a arranged at three positions on the outer peripheral portion of the second fixed cylinder 62 slide in the peripheral groove portion 54b. . Therefore, the focus ring 54 can be rotated endlessly at a fixed position. The focus ring 54 has the Corobis 62a.
Is formed with a hole 54c. Also,
Inner teeth 54a are formed on the focus ring 54, and the inner teeth 54a mesh with a gear 74 as a transmission means. That is, the gear 74 is rotated by rotating the focus ring 54. The second pulley 72 is configured coaxially with the gear 74, and the shaft thereof is held by the fixed cylinder 55.
The second pulley 72 is connected to the first pulley 71 and the winding portion 73 by the flexible linear body 70.

In this embodiment, the winding portion 73 is held by a movable moving member 76, the movement of the optical axis other than the rotation direction is restricted by the groove 55b provided in the fixed barrel 55, and The flexible linear member 7 is formed by the biasing member 77.
It is biased in the direction of increasing the tension of 0. Also,
The flexible linear member 70 is wound around the first pulley 71 once, and is connected to the second pulley 72 and the winding portion 73. Reference numeral 75 denotes an axis extending in the optical axis direction, which is fixed to the fixed barrel 55. The flexible linear member 70 passes through this outer circumference to prevent the flexible linear member 70 from touching the cam ring 60.

Next, the operation of the lens barrel of the second embodiment having the above structure will be described. Autofocus operation of the focusing lens group 2 by the photographer (motor drive)
When the drive is to be performed by, a focusing switch (not shown) is operated. Then, a voltage is supplied to the motor according to the operation of a control circuit (not shown), and as a result, the output shaft of the drive unit 61 rotates, so that the first pulley 7 is rotated.
1 rotates. The flexible linear member 70 is attached to the first pulley 71.
The cam ring 60 depends on the direction of rotation because the
Moves in the illustrated A or B direction around the optical axis. As a result, the movable lens barrel 59 moves back and forth in the optical axis direction.

Further, the frictional force F ₅ between the focus ring 54 and the fixed barrels 55 and 62 is adjusted so that the second pulley 72 does not rotate when the motor is driven. The relationship with the transmission force F ₆ to the flexible linear body 70 is set so that F ₅ > F ₆ .

The value of F ₅ can be adjusted by the position of the Corobis 62a, the lubricating oil applied between the focus ring 54 and the fixed cylinders 55 and 62, and the like.

On the other hand, the photographer sets the focusing lens group 5
When the user wants to move 2 by the manual focus operation, when the focus ring 54 is rotated, the internal tooth portion 54a and the gear 74 are transmitted to rotate the second pulley 72. At this time, the relationship between the frictional force F ₇ between the first pulley 71 and the flexible linear body 70 and the rotational operation force F ₈ of the focus ring 54 transmitted by the flexible linear body 70 is F ₇ > F ₈ Is set to be

Therefore, the pulley 71 can rotate the cam ring 60 without rotating. In addition, during autofocus operation,
The first pulley 7 during both manual focus operation
The stopper receiving portion 61 provided on the cam ring so that the first and second pulleys 72 and the winding portion 73 do not collide with each other.
The a and 61b contact the stoppers 55c and 55d of the fixed cylinder, and the movement range is restricted. If the focus ring 54 may be further rotated after the cam ring has moved to the infinite end or the closest end, the winding portion 73 of the moving member 76 is turned against the biasing member 77. Moves slightly in the direction B in the figure, the tension of the flexible linear member 70 decreases, and the second pulley 72 at this time
Friction force F ₉ between the flexible linear body 70 and the transmission force F ₆ to the flexible linear body 70 when driven by the motor and the focus ring 54 transmitted by the flexible linear body 70. the relationship between the rotational operating force F _{8 is, F 8> F 9> F} 6 , and the second pulley 12 runs idle, so that prevent destruction.

FIG. 4 is a cross-sectional view of the third embodiment, in which the moving direction of the movable lens barrel 9 by the rotation of the focus ring 4 of the first embodiment is changed to the second pulley 12 and the pulley 23 in FIG.
In this case, the rotation direction of the flexible linear body is reversed by connecting the flexible linear body to the first pulley and the winding portion as shown in the figure.

FIG. 5 is a sectional view of the fourth embodiment, and FIG. 6 is FIG.
6 is a view taken along line AA of FIG. 5, in which the first pulley 71 is replaced with the pulley 80 in FIG.
By providing the shafts 78 and 79 which are held by the fixed barrel so as not to interfere with other members, the rotation direction of the cam ring 60 by the rotation of the focus ring 54 of the second embodiment is reversed.

As described above, since the flexible linear members are used as shown in FIGS. 4, 5 and 6, the rotation directions of the focus rings 4 and 54, the movable lens barrel 9 and the cam ring are easily changed. 60
The direction of movement of can be reversed. This increases the degree of freedom in designing the cam groove shape of the cam ring.

Although the focusing operation has been described in the present embodiment, there is no difference even if this operation is directly used for the zooming operation.

Further, a similar effect can be obtained by using a timing belt, a V belt or the like instead of the flexible linear member 10.

Further, in the drawings of the embodiments, the lens barrels of two groups are shown for convenience, but the present invention can be easily applied to a lens configuration of three or more groups.

[0038]

As described above, in the lens barrel of the present invention, when the operation of the manual operation member such as the manual focus operation is immediately performed immediately after the operation based on the drive of the drive source such as the auto focus operation, The operation based on the drive of the drive source can be switched to the operation of the manual operation member without requiring any special switching means simply by operating the manual operation member.

Further, since the lens barrel of the present invention can be constructed without using a motor having a large self-holding force such as a vibration wave motor, it is possible to use an inexpensive DC motor or the like as the lens driving motor. Since it is possible to construct the lens with almost the same number of parts as the lens having the conventional switching means without inserting the pressing means for obtaining the holding force, it is possible to significantly reduce the cost.

Further, in the lens barrel of the present invention, the relationship between the directions of movement of the rotary ring member and the manual operation member can be reversed by the winding method of the winding member of the flexible linear member. This has the effect of increasing the degree of freedom in design.

[Brief description of drawings]

FIG. 1 is a sectional view of a lens barrel according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a lens barrel according to a second embodiment of the present invention.

3 is a cross-sectional view taken along the line AA of the lens barrel in FIG.

FIG. 4 is a sectional view of a lens barrel according to a third embodiment of the present invention.

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

6 is a cross-sectional view taken along the line AA of the lens barrel in FIG.

[Explanation of symbols]

1.51 First lens group 2.52 Focusing lens group (movable optical member) 4.54 Focus ring (manual operating member) 5.17.55 Fixed cylinder 6.56 Mount 7.57 Electrical mounting board 9.59 Moving barrel (movable optical system) 10.70 Flexible linear body 14.71 First pulley (first rotatable member) 12.72 Second pulley (second rotatable member) 11/73 Winding part 4a / 54a Internal tooth part (transmission means) 22 First gear (transmission means) 13 Second gear (transmission means) 74 Gear (transmission means) 15/77 Energizing member 21/61 Drive Unit (driving means)

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[Procedure amendment]

[Submission date] November 8, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0015

[Correction method] Change

[Correction content]

Here, the urging member 15 is urged in a direction to apply tension so that the first pulley 14 does not idle, and the drive unit is transmitted to the first pulley 14 by the flexible linear member 10. The relationship between the driving force F ₂ of F. 21 and the rotational operation force F ₁ of the focus ring 4 transmitted to the second pulley 12 by the flexible linear member 10 is set so that F ₁ > F _2. There is.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0019

[Correction method] Change

[Correction content]

Further, the first pulley 14 and the flexible linear member 1
The relationship between the frictional force F _{3 of} 0 and the rotational operation force F ₁ of the focus ring 4 transmitted to the second pulley 12 by the flexible linear member 10 is that F ₃ > F ₁ is set.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

Therefore, the movable lens barrel 9 moves in the optical axis direction without rotating the first pulley 14. It should be noted that, in both the autofocus operation and the manual focus operation, the first
The stopper receiving portion 9 provided in the movable lens barrel 9 so that the pulley 14 and the second pulley 12 may not collide with each other.
The a and 9b contact the stopper portions 17c and 5c of the fixed cylinder, and the movement range is restricted. If the focus ring 4 may be further rotated after the movable lens barrel 9 is moved to the infinite end or the closest end, the wrapping portion 11 of the moving member 16 is moved to the urging member 15. On the contrary, it slightly moves to the mount side, the tension of the flexible linear member 10 decreases, and the frictional force F ₄ between the second pulley 12 and the flexible linear member 10 at this time and the flexible linear member 10 Drive unit 21 transmitted to the first pulley 14 by
Driving force F ₂ of the focus ring 4 transmitted to the second pulley 12 by the flexible linear member 10
Relationship with the _{1, F 1> F 4> F} 2 , and the second pulley 12 runs idle, so that prevent destruction.

[Procedure amendment 4]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

Claims (6)

[Claims] 1. A lens barrel for moving an optical member by operating a manual operation member and driving a drive source, comprising: a first rotatable member that rotates in response to an operation of the manual operation member; A winding drive mechanism including at least a second rotatable member that is rotated by being driven, a first rotatable member, and a flexible linear member that is wound around the second rotatable member. And the winding mechanism is configured to move one of the first and second rotatable members in the optical axis direction regardless of which of the first and second rotatable members rotates. A lens barrel, further comprising an interlocking mechanism for moving the optical member in the optical axis direction based on the movement of the one rotatable member in the optical axis direction. 2. In a lens barrel for moving an optical member by operating a manually operated member and driving a drive source, a flexible linear body and the flexible linear body are wound around at least one rotation, A first rotatable member that moves together with the member, a second rotatable member that is wound around the flexible linear body, and is disposed at a position sandwiching the first rotatable member, and a winding portion. A lens barrel comprising drive means for driving the first rotatable member and transmission means for transmitting an operation of the manually operated member to the second rotatable member. 3. The lens barrel according to claim 2, wherein the driving means is integrated with the optical member. 4. A force F ₁ for moving the optical member by operating the manual operation member, a force F ₂ for driving the manual operation member by the driving means, and the flexible linear body and the first member. Frictional force F ₃ with a rotatable member
4. The lens barrel according to claim 2 or 3, wherein the relationship of F ₃ > F ₁ > F ₂ is set. 5. The wrapping portion is arranged on a moving member that can move with respect to the fixed cylinder, and urging means for urging the moving member in a direction to increase the tension of the flexible linear body is provided. The lens barrel according to claim 2, 3 or 4, characterized in that. 6. A lens barrel for moving an optical member by operating a manual operation member, wherein a flexible linear member and a rotatable member interlocked with the manual operation member and wound around the flexible linear member. And a winding portion around which the flexible linear member is wound, and the optical member is rotated around the optical axis integrally with the winding portion by the transmission force of the flexible linear member. A lens barrel having a rotating ring member to be moved.