JP4495911B2 - Lens barrel - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a lens barrel capable of moving a movable barrel in the optical axis direction by manual operation.
[0002]
[Prior art]
Some conventional lens barrels are equipped with two automatic and manual operation mechanisms and can selectively perform focus adjustment. In such a lens barrel, when automatic focus adjustment is performed, the driving of the motor for automatic focusing is transmitted to the lens moving means by gear connection or the like. When performing manual focus adjustment, manual focus operation is performed by rotating a manual operation ring such as a focus ring.
[0003]
In such a lens barrel, if the rotational load of the manual operation ring is too light, it is not preferable because a manual operation when performing focus adjustment using the manual operation ring cannot provide a profound feeling. For this reason, it is known that a frictional resistance is applied to the rotation of the manual operation ring by a friction material such as a leaf spring or rubber, and a good operation feeling is obtained by applying an appropriate load to the rotation operation of the manual operation ring. (For example, refer to Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent No. 2561921
[Problems to be solved by the invention]
However, in the configuration of the lens barrel as described above, a frictional resistance is applied to the rotation of the manual operation ring with a leaf spring, rubber or the like. It was difficult to feel smoothness and luxury in the rotation operation. Further, when friction resistance is applied using a leaf spring or rubber, there is a problem that it is difficult to manage the rotational torque of the manually operated ring during mass production.
[0006]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a lens barrel that stabilizes the rotational torque of a manual operation ring and has smoothness and a high-class feeling in manual operation.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, a lens barrel according to the present invention includes a fixed tube, a manual operation ring rotatably supported by the fixed tube, a lens and a manual operation ring in conjunction with the rotation operation of the manual operation ring. In a lens barrel having a moving barrel that moves in the direction of the optical axis , oil for adjusting the frictional force is slidably brought into sliding contact with a manually operated ring on a fixed barrel or an annular member that is integrally fixed to the fixed barrel. The impregnated artificial suede is fixed, and the force when the manual operation ring is rotated by friction between the fixed cylinder or the annular member and the artificial suede is adjusted. Further, an artificial suede impregnated with oil for adjusting the frictional force is fixed to a fixed cylinder or an annular member integrally fixed to the fixed cylinder so as to be in sliding contact with the manual operation ring, and the manual operation ring and the artificial suede are fixed. The amount of force when rotating the manual operation ring may be adjusted by friction between the manual operation ring.
[0008]
The lens barrel of the present invention includes a manual operation ring that is rotatably supported by a fixed cylinder, a drive cylinder that is rotatably supported by the fixed cylinder and rotates in conjunction with the rotation operation of the manual operation ring, and the drive cylinder A movable cylinder that moves in the direction of the optical axis in conjunction with the rotation of the motor, and a motor drive ring that rotates by driving a motor that is rotatably supported by a fixed cylinder to rotate the drive cylinder. It is a lens barrel in which one of the rings is stopped and the other is rotated so that the drive cylinder is selectively rotated by either the manual operation ring or the motor drive ring, and is fixed to the manual operation ring. The artificial suede impregnated with oil for adjusting the frictional force is fixed so as to be in sliding contact with the annular member integrally fixed to the cylinder or the fixed cylinder, and the friction between the fixed cylinder or annular member and the artificial suede is fixed. Overcoming When the drive ring is rotated by rotating the dynamic operation ring and the drive cylinder is rotated by the motor drive ring, the rotation of the manual operation ring is prohibited by the friction between the fixed cylinder or the annular member and the artificial suede. It is characterized by that. Also, an artificial suede impregnated with oil for adjusting the friction force is fixed to a fixed cylinder or an annular member integrally fixed to the fixed cylinder so as to be in sliding contact with the manual operation ring, and the manual operation ring and the artificial suede are fixed. When rotating the drive ring by rotating the manual operation ring overcoming the friction between the manual operation ring and the motor driven ring, the friction of the manual operation ring is caused by the friction between the manual operation ring and the artificial suede. The rotation may be prohibited.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is an external perspective view of a lens barrel 10 of the present invention. The lens barrel 10 includes a moving cylinder 12 that holds the lens 11, a fixed cylinder 13 that is fixed to the camera body and holds the moving cylinder 12 movably in the optical axis direction, a focus ring 14 that is a manual operation ring, The cover barrel 15 is attached so as to cover the rear end of the fixed cylinder 13.
[0011]
In this lens barrel 10, the movable barrel 12 is movable back and forth along the optical axis between the retracted position (retracted position) shown in FIG. 1 (A) and the extended position shown in FIG. 1 (B). Has been. The movement of the moving cylinder 13 in the optical axis direction is performed by two kinds of methods. The first method is performed by rotating the focus ring 14 by a photographer. The second method is performed by driving a motor of a lens driving unit provided in the fixed cylinder 13.
[0012]
Next, the configuration of the lens barrel 10 will be described with reference to the exploded perspective view of FIG. A fixed cylinder 13 is provided at the rear end of the lens barrel 10, and the fixed cylinder 13 is fixed to the camera body. A lens drive unit (not shown) is provided on the back surface of the fixed cylinder 13. The lens driving unit is driven by a motor, and the output gear 20 is exposed from the opening 19 at the rear end of the fixed cylinder 13. The output gear 20 meshes with a gear 31 provided on the rear side of the motor drive ring 30 described later, and the rotational drive force from the motor is transmitted to the gear 31 of the motor drive ring 30. Further, a guide groove 21 for guiding the movable cylinder 12 in the optical axis direction is provided on the outer periphery of the fixed cylinder 13.
[0013]
The moving cylinder 12 includes a moving cylinder main body 24 that holds the lens 27 and a lens holder 25 that holds the lens 11. The lens holder 25 has a focus ring 14 (to be described later) attached to the lens barrel 10. After that, it is attached to the movable cylinder body 24. A cam pin 26 is provided on the outer periphery of the rear end of the movable cylinder main body 24 and engages with the guide groove 21 described above. Thereby, the movement cylinder 12 is guided to move in the optical axis direction.
[0014]
The motor drive ring 30 is attached to the rear side of the fixed cylinder 13 so that the gear 31 formed on the inner periphery on the rear side thereof meshes with the output gear 20 of the lens drive unit as described above. A gear 32 is formed on the front side of the motor drive ring 30.
[0015]
A planetary gear 34 that meshes with the gear 32 on the front side of the motor drive ring 30 is rotatably supported on the outer peripheral surface of the cam cylinder 33, and the cam pin 26 is engaged with the outer peripheral surface. The cam groove 35 is formed so as to draw a spiral. The cam cylinder 33 is disposed in front of the motor drive ring 30 so that the cam groove 35 engages with the cam pin 26 of the movable cylinder main body 24 and the planetary gear 34 meshes with the gear 32 of the motor drive ring 30. Is done. In the present embodiment, the cam cylinder 33 corresponds to a drive cylinder.
[0016]
An index ring 36 is attached to the cam cylinder 33 with a screw or the like so as to cover the cam cylinder 33 from the outside. When the cam cylinder rotates, it rotates integrally with the cam cylinder. An indicator 37 is displayed on the outer peripheral surface of the indicator ring 36 and is observed by the photographer through a display window 38 provided on the outer periphery of the cover barrel 15.
[0017]
A focus ring 14 is disposed in front of the cam cylinder 33. As shown in FIG. 3, the focus ring 14 includes a rubber cover 40, a ring body 41, a focus ring gear 43 having a gear 42 formed on the back side, and an artificial suede 44 as a friction material. Yes.
[0018]
On the outer periphery of the focus ring gear 43, an artificial suede 44 is wound around a portion indicated by hatching in the drawing and attached with an adhesive or the like. Artificial suede is artificial leather composed of ultra-fine fibers, and as this artificial suede 44, for example, EXEN (registered trademark) is used. The artificial suede 44 is a friction material and abuts against the inner peripheral surface of the cover barrel 15. When the focus ring 14 is rotated, the artificial suede 44 comes into sliding contact with the inner peripheral surface of the cover barrel 15 and rotational resistance is generated by friction. The friction resistance of the artificial suede 44 is more stable than when a leaf spring or a rubber ring is used, and the rotational torque can be kept constant.
[0019]
Due to the frictional resistance of the artificial suede 44, the rotational torque increases when the focus ring 14 is rotated. However, the artificial suede 44 is coated with silicone oil, which further increases the frictional resistance and increases the rotational torque. ing. Since the artificial suede 44 is composed of ultrafine fibers, the liquid retainability is high, and the applied oil does not flow out even at high and low temperatures. Also, other oils may be used instead of silicone oil.
[0020]
Further, since the rotational resistance of the focus ring 14 is set larger than the rotational resistance of the cam cylinder 33, the rotational torque of the focus ring 14 is larger than the rotational torque of the cam cylinder 33. Further, if the width of the artificial suede 44 is changed, the friction coefficient is changed by increasing or decreasing the contact area with the inner peripheral surface of the cover barrel. Thereby, a rotational torque can increase / decrease and an operational feeling can be changed.
[0021]
A screw hole 45 is formed in the outer periphery in front of the focus ring gear 43, and an insertion hole 46 through which a screw is inserted is formed in the outer periphery in the rear of the ring body 41. A screw 47 is inserted into the insertion hole 46 and fixed with a screw hole 45. Thereby, the focus ring gear 43 is fixed to the ring body 41.
[0022]
Leaf springs 49 are attached to the focus ring gear 43 at three locations by screws 48. The leaf spring 49 is a friction material and is urged so that the protrusion 50 provided on the upper surface always abuts against the inner peripheral surface of the cover barrel 15. Thereby, when the focus ring 14 rotates, the protrusion 50 slides on the inner peripheral surface to generate a frictional resistance. The leaf spring 50 is attached as a preventive measure when the artificial suede, which is a friction material, deteriorates.
[0023]
Next, the operation of the above configuration will be described. FIG. 4 is a side sectional view of the lens barrel 10. 4A shows the retracted state (retracted state) of the movable cylinder 12, and FIG. 4B shows the extended state.
[0024]
First, the first method (operation by the focus ring) will be described. When the focus ring 14 is rotated by the photographer, the planetary gear 34 is engaged with the gear 42 of the focus ring gear 43, so that the planetary gear 34 starts rotating. On the other hand, the motor drive ring 30 in which the planetary gear 34 meshes with the opposite side (rear side) is set to have a larger rotational resistance than the cam cylinder 33 and does not rotate because the rotational torque is larger than that of the cam cylinder 33. For this reason, the planetary gear 34 rolls on the gear 32 and revolves while rotating. Since the planetary gear 34 is pivotally supported by the cam cylinder 33, the cam cylinder 33 is rotated by the revolution of the planetary gear 34.
[0025]
Due to the rotation of the cam cylinder 33, the cam surface of the cam groove 35 presses the cam pin 26 of the movable cylinder 12, so that the movable cylinder 12 is retracted along the guide groove 21 of the fixed cylinder 13 as shown in FIG. It moves in the optical axis direction between the position and the feeding position shown in FIG.
[0026]
As described above, when the focus ring 14 is rotated by the photographer, the artificial suede 44 and the inner surface of the cover barrel 15 are brought into sliding contact with each other to generate frictional resistance, so that resistance is added to the rotating operation. Further, since the protrusion 50 provided on the leaf spring 49 is always in contact with the inner surface of the cover barrel, the friction between the protrusion 50 and the cover barrel 15 is caused when the focus ring 14 is rotated. Resistance is generated, and resistance is added to the rotation operation.
[0027]
As a result, when the focus ring 14 is operated to rotate, it does not easily rotate lightly, and since a resistance force is applied to the rotation, the rotational torque is increased, the operational feeling becomes heavier, and the heavy feeling and luxury A feeling is obtained. Further, since the artificial suede 44 is coated with silicon oil, a unique moist feeling can be obtained with respect to the rotation operation. Since the artificial suede 44 has higher durability than rubber and leaf springs, the friction coefficient due to deterioration is small, so that the rotational torque is stabilized over a long period of time.
[0028]
Next, a second method for moving the moving cylinder in the optical axis direction by the lens driving unit will be described.
[0029]
The output gear 20 of the lens driving unit meshes with a gear 31 provided on the rear side of the motor driving ring 30, and the rotational driving force from the motor is transmitted to the gear 31 of the motor driving ring 30, so that the motor driving ring 30 is rotated. Since the gear 32 formed on the front side of the motor drive ring 30 meshes with the planetary gear 34, the planetary gear 34 starts rotating. The planetary gear 34 is pivotally supported by the cam cylinder 33 so that the rotational torque of the focus ring 14 is larger than the rotational torque of the cam cylinder 33, so that the focus ring 14 does not rotate and the planetary gear 34 does not rotate. 14 on the gear 42, and the planetary gear 34 starts to revolve while rotating.
[0030]
Due to the revolution of the planetary gear 34, the cam cylinder 33 that pivotally supports the planetary gear 34 also rotates. As a result, similarly to the manual operation of the focus ring 14, the movable cylinder 12 moves between the feeding position in FIG. 4A and the feeding position in FIG. 4B.
[0031]
In the present embodiment, the leaf spring is used as the friction material together with the artificial suede. However, the leaf spring may not be used. Moreover, although silicon oil was included in the artificial suede, the present invention is not limited to this, and other oil may be included.
[0032]
Further, in this embodiment, the artificial suede is fixed to the manual operation ring so as to be in sliding contact with the cover barrel which is an annular member integrally fixed to the fixed cylinder. The artificial suede may be fixed to the manual operation ring so as to come into contact.
[0033]
Further, in the present embodiment, the artificial suede is fixed to the manual operation ring. However, the present invention is not limited to this, and the manual operation ring and the sliding member are fixed to the fixed cylinder or the annular member integrally fixed to the fixed cylinder. Artificial suede may be fixed so as to contact.
[0034]
【The invention's effect】
As described above, the focus lens barrel of the present invention is provided with an artificial suede coated with oil as a friction material on a focus ring that is a manually operated ring, and is manually operated by the frictional force between the artificial suede and the cover barrel. Since the rotation of the operation ring is controlled, the rotation torque of the manual operation ring is increased and the rotation resistance is kept constant, so it is possible to feel a moderate load and enjoy good manual operation. A smooth, profound feeling and luxury can be obtained during operation.
[0035]
In addition, since this artificial suede has higher durability than rubber and leaf springs, there is little change in the coefficient of friction due to deterioration, so that the rotational torque is kept constant over a long period of time, so there is little deterioration in quality.
[Brief description of the drawings]
FIG. 1 is an external perspective view of a focus lens barrel in which a lens barrel of the present invention is implemented.
FIG. 2 is an exploded perspective view showing an internal configuration of a focus lens barrel.
FIG. 3 is an exploded perspective view showing a configuration of a focus ring.
FIG. 4 is a side sectional view of a focus lens barrel.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Lens barrel 11, 27 Lens 12 Moving cylinder 13 Fixed cylinder 14 Focus ring 15 Cover barrel 30 Motor drive ring 33 Cam cylinder 41 Ring main body 42 Focus ring gear 44 Artificial suede 48 Leaf spring 50 Protrusion part

Claims (4)

In a lens barrel comprising a fixed cylinder, a manual operation ring rotatably supported by the fixed cylinder, and a movable cylinder that holds the lens and moves in the optical axis direction in conjunction with the rotation operation of the manual operation ring ,
An artificial suede impregnated with oil for adjusting a frictional force is fixed to the manual operation ring so as to be in sliding contact with the fixed cylinder or an annular member integrally fixed to the fixed cylinder. A lens barrel characterized by adjusting a force when the manual operation ring is rotated by friction between an annular member and the artificial suede. In a lens barrel comprising a fixed cylinder, a manual operation ring rotatably supported by the fixed cylinder, and a movable cylinder that holds the lens and moves in the optical axis direction in conjunction with the rotation operation of the manual operation ring ,
An artificial suede impregnated with oil for adjusting a frictional force is fixed to the fixed cylinder or an annular member integrally fixed to the fixed cylinder so as to be in sliding contact with the manual operation ring. A lens barrel characterized by adjusting the force when the manual operation ring is rotated by friction with the artificial suede. A manual operation ring rotatably supported by the fixed cylinder, a drive cylinder rotatably supported by the fixed cylinder and rotating in conjunction with the rotation operation of the manual operation ring, and an optical axis in conjunction with the rotation of the drive cylinder A moving cylinder that moves in a direction and a motor drive ring that rotates by driving a motor rotatably supported by a fixed cylinder, and stops one of the manual operation ring and the motor drive ring and In the lens barrel in which the drive cylinder is selectively rotated by either the manual operation ring or the motor drive ring by rotating,
An artificial suede impregnated with oil for adjusting a frictional force is fixed to the manual operation ring so as to be in sliding contact with the fixed cylinder or an annular member integrally fixed to the fixed cylinder. When rotating the drive ring by overcoming the friction between the annular member and the artificial suede and rotating the manual operation ring, and rotating the drive cylinder with the motor drive ring, the fixed cylinder or the A lens barrel characterized in that rotation of the manual operation ring is prohibited by friction between an annular member and an artificial suede. A manual operation ring rotatably supported by the fixed cylinder, a drive cylinder rotatably supported by the fixed cylinder and rotating in conjunction with the rotation operation of the manual operation ring, and an optical axis in conjunction with the rotation of the drive cylinder A moving cylinder that moves in a direction and a motor drive ring that rotates by driving a motor rotatably supported by a fixed cylinder, and stops one of the manual operation ring and the motor drive ring and In the lens barrel in which the drive cylinder is selectively rotated by either the manual operation ring or the motor drive ring by rotating,
An artificial suede impregnated with oil for adjusting a frictional force is fixed to the fixed cylinder or an annular member integrally fixed to the fixed cylinder so as to be in sliding contact with the manual operation ring. When rotating the drive ring by overcoming the friction between the artificial suede and rotating the manual operation ring, and rotating the drive cylinder with the motor drive ring, the manual operation ring and the artificial suede A lens barrel characterized in that rotation of the manually operated ring is prohibited by friction between the lens barrel and the lens barrel.

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