JPH10268178A - Zoom lens device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an internal focusing zoom lens device having the capability of reducing overall length, with lens groups moved to such position as near each other at the time of out of photographic service such as in transportation, and enlarging the overall length via the travel of respective lens groups to such positions as allowing photographing when necessary, and further capable of making the device un-bulkyl for transportation or the like, and increasing a variable power factor at the time of taking a photograph. SOLUTION: A first cam cylinder 52 as well as a second cam cylinder is rotated on the output rotation of a drive motor 55 laid on the upper part of a fixed frame 50. Also, the first cam cylinder 52 is formed to move a first group lens 11 and a third group lens between such a position as housed in the fixed frame 50 and unusable for photographing, and a photographing position for taking a photographic. In addition, a first and a third cam grooves 61, 63 are formed for maintaining the group lens at constant positions during a variable power operation, and the second cam cylinder is formed to have a second and a fourth cam grooves 62, 64 for causing the motion and variable power travel of the second and the fourth group lens 21 and 41 between a storage position and a photographing position. Also, an internal focusing system is adopted for keeping the first group lens 11 projected from the fixed frame 50 at the photographing position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens apparatus for continuously changing a focal length, and more particularly to an inner focus type zoom lens apparatus for moving a rear lens in an optical axis direction to focus. is there.

[0002]

2. Description of the Related Art In recent years, cameras equipped with a zoom lens device have become widespread so that anyone can easily enjoy photography. A conventional two-group zoom lens including a front lens group and a rear lens group is used in a zoom lens device of this type of a popular camera in order to shorten the overall length of the lens and reduce the size. Have been.

FIGS. 13 and 14 show two cameras mounted on a camera.
FIG. 13 is a schematic cross-sectional view showing a group zoom. FIG. 13 shows a state in which the photographing lens is at a wide-angle position, and FIG. A drive lens barrel 3 rotatably connected by a helicoid 2 is accommodated in a fixed lens barrel 1 fixed to a camera body (not shown), and a movable lens barrel 5 rotatably connected to the drive lens barrel 3 by a helicoid 4. Is housed. The movable lens barrel 5 is connected to a guide tube 6 supported at the rear end of the drive lens barrel 3 so as not to rotate even by the rotation of the drive lens barrel 3, and the rotation is prevented. Have been. The front lens group 7 is attached to the movable lens barrel 5, and an engagement pin implanted in a lens frame 9 a holding the rear lens group 9 in a cam groove 8 formed on the inner peripheral surface of the driving lens barrel 3.
The rear lens group 9 is engaged with the driving lens barrel 3 and held. Therefore, when the drive lens barrel 3 rotates,
The helicoid 2 causes the driving lens barrel 3 to advance and retreat in the optical axis direction with respect to the fixed lens barrel 1, and the movable lens barrel 5 advances and retreats to the driving lens barrel 3 by the helicoid 4. As the drive lens barrel 3 and the movable lens barrel 5 advance and retreat, the front group lens 7 advances and retreats together with the movable lens barrel 5, and the rear group lens 9 advances and retreats by being guided by the cam groove 8. The rear lens group 9 moves forward and backward while maintaining a predetermined optical relationship to change the magnification.

On the other hand, in a zoom lens device of a camera using an image pickup device such as a CCD, such as a video camera, a high magnification design is relatively easy, and the position of an exit pupil can be set far from an image plane. For this purpose, a so-called inner focus type zoom lens device called an inner focus, a rear focus, or the like, which includes three or more lens groups and moves and focuses a rear lens, is used.

[0005]

The zoom lens device used in the conventional popular type camera is a two-unit zoom lens, so it is difficult to design a zoom lens having a high zoom ratio.
A magnification of about 2 to 3 times is the most widespread. On the other hand, with the spread of this type of camera, it has been demanded to be able to equip a zoom lens device with a higher magnification so as to easily enjoy photographing.

In order to meet this demand, it is conceivable to mount an inner focus type zoom lens device used in a video camera or the like on this type of popular camera. However, since the inner lens type zoom lens device has a long overall lens length and the position of the first lens unit at the forefront is fixed, it is difficult to reduce the size of the camera body when equipped with the camera. Will be.

SUMMARY OF THE INVENTION As described above, in order to meet the demand for mounting a high-magnification zoom lens device on a camera as described above, the camera is mounted on the camera, and the size of the camera is reduced especially when the camera is carried. It is an object of the present invention to provide a zoom lens apparatus of an inner focus system which can perform the following.

[0008]

As a technical means for achieving the above object, a zoom lens apparatus according to the first aspect of the present invention comprises three or more lens groups, and the zoom lens apparatus is provided at the forefront located on the object side. In the inner focus type zoom lens device that moves a predetermined moving lens group located behind the first group lens in the optical axis direction to focus, the lens groups are moved by the applied operating force to the respective lens groups. Can be moved in the optical axis direction between a storage position where it is close to and cannot be used for shooting and a shooting position where it can be used for shooting. It is characterized in that the lens group is movable in the direction of the optical axis while maintaining a predetermined optical relationship to change the magnification.

When the zoom lens device is not used for photographing, the lens group is moved to the storage position.
In this state, since the lens groups are located close to each other, the total length of the zoom lens device is close to the shortest, so that the zoom lens device is not bulky when being carried or stored. For this reason, the advantage of miniaturization of the zoom lens device is not lost.

[0010] Further, in the case of photographing, the lens group is moved to the photographing position. In this state, by moving a predetermined movable lens other than the first group lens, a variable power operation can be performed. In addition, since the zoom lens apparatus uses the inner focus method, the magnification can be increased.

The operating force applied to move the lens group is generated by a photographer manually operating a predetermined component, or generated by operating a driving source such as an electric motor. There is.

In order to minimize the overall length of the lens group when the lens group is in the retracted position in relation to the lens frame holding the lens group, the zoom lens apparatus according to the second aspect of the present invention has three groups. An inner focus type zoom lens apparatus comprising the above lens groups, and moving a predetermined moving lens group located behind the foremost first lens group located on the subject side in the optical axis direction to focus. Each of the lens groups is held in a predetermined lens frame, the lens frame is slidably connected to the fixed frame in the optical axis direction, and the lens groups approach each other by the applied operating force. The first lens group can be moved in the optical axis direction between a storage position where the camera cannot be used for photographing and a photographing position where photographing can be performed. The fixed frame Slide to a position protruding from the lens unit and maintain the position, and the predetermined movable lens group is maintained in a predetermined optical relationship to be movable in the optical axis direction to change the magnification. The entirety of the lens frame is housed in a fixed frame.

When the lens group is in the retracted position, the total length is determined by the total length of the fixed frame. In addition, since each lens frame is connected to the fixed frame, the sliding of these lens frames in the optical axis direction can be guided by the fixed frame.

According to a third aspect of the present invention, there is provided a zoom lens apparatus comprising: a first type transmitting means for transmitting an operating force to a lens group which is maintained at a fixed position during zooming; A second type transmitting means for transmitting an operating force to the lens group to be operated, wherein the first type transmitting means stores the lens group connected to the first type transmitting means by the input operating force at a storage position and a photographing position. And in the state at the time of photographing, the operation force is not transmitted to the lens group, and the second type transmission means transmits the operation force to the second type transmission means by the input operation force. By moving the linked lens group between the storage position and the photographing position, and transmitting the operating force to the lens group in the photographing position, the lens group maintains a predetermined optical relationship. It is characterized by being moved.

For example, in the case of a zoom lens apparatus having four lens groups, and the first lens group and the third lens group are not moved at the time of zooming, these first and second lens groups may be used.
A third lens group is connected to the first type transmission means. These lens groups move between the storage position and the photographing position in response to the operation force, and are maintained at the photographing position regardless of the operation force during zooming. Further, the second group lens and the fourth group lens are connected to the second type transmission means. These lens groups move between the retracted position and the photographing position in response to an operation force, and at the time of zooming, maintain a predetermined optical relationship in cooperation with the other lens groups in the optical axis direction. Go to
This will change the focal length.

Note that the lens group that can be positioned at the same position in both the storage position and the photographing position does not need to be moved. Therefore, the lens group is not connected to any of the above-described transmission means and is independent of the operating force. To be configured.

Further, the first type transmitting means and the second type transmitting means may be provided on separate parts corresponding to the respective lens groups, or may correspond to a plurality of lens groups in one part. It is also possible to form the first or second type of transmitting means and drive each lens group by the operation of the component.

As described above, the operation force may be generated manually or by using the power of a motor or the like. In the zoom lens apparatus according to the invention of claim 4, the operation force is generated. It is characterized in that the operating force is applied from a single part.

That is, by operating one member, the above-described operating force is obtained, and the lens group can be moved between the retracted position and the photographing position, and the variable power drive can be performed.

Further, the zoom lens device according to the invention of claim 5 is characterized in that the operating force is applied from a plurality of parts.

For example, the power of the motor is used to move the lens group between the storage position and the photographing position, and the variable magnification drive is manually performed. The transmission mechanism for driving the lens groups can be changed so as to fulfill a sufficient function as a zoom lens device, such as a structure in which the lens group is moved by one motor and the other lens group is moved by another motor.

Further, in the zoom lens device according to the invention of claim 6, the first type transmitting means and the second type transmitting means are formed by cam means, and the first type transmitting means includes the first type transmitting means.
It is characterized in that a cam curved portion for moving the lens group connected to the seed transmitting means between the retracted position and the photographing position and a dead zone for not transmitting the operating force to the lens group are formed.

That is, an engaging pin or the like is implanted in the lens frame holding the lens group, and the engaging pin is connected to the cam groove. In the cam groove forming the cam means of the first type transmission means, the cam curve portion and the dead zone portion are formed, and from the storage position to the photographing position, the engaging pin is connected to the cam curve portion to form the cam curve portion. In the case where the lens group is moved by being guided by the section and is driven for zooming, if the engaging pin of the lens group connected to the first type transmission means is linked to the dead zone, the zooming operation can be performed. These lens groups do not move.
Further, the lens group connected to the second type transmission means is guided by the cam groove to move between the storage position and the photographing position, and perform a zooming operation.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a zoom lens apparatus according to the present invention will be specifically described based on preferred embodiments shown in the drawings. 1 to 6 show a first embodiment, and FIGS. 7 to 12 show a second embodiment.

FIG. 1 is a cross-sectional view showing a part of a right side surface of the zoom lens apparatus according to the present invention, in which a part of a right side surface of the zoom lens apparatus is in a retracted position. FIG. 3 is a cross-sectional view showing a part of a right side surface of the lens group at the photographing position and on the wide-angle side, and FIG. 4 is a cross-sectional view of the same on the telephoto side. 1 and 3, 4
As shown in the figure, the zoom lens device has a first group lens 11 at the forefront on the subject side and a second group lens 21
However, it has a five-group configuration in which the third lens group 31 is located behind, the fourth lens group 41 is located behind, and the fifth lens group 48 is located at the rear end.

The first lens group 11 is held at the front of the first lens frame 12. The rear of the first lens frame 12 extends appropriately rearward, and a part of the rear extends outward and further extends rearward. A seat 12a is formed, and a first engagement pin 13 is provided on the seat 12a so as to protrude outward. A fork 14 projecting downward is provided at a lower portion of the rear of the first lens frame 12.
The fork portion 14 has a cut portion.

The second lens group 21 is held at the front of the second lens frame 22. The rear of the second lens frame 22 extends appropriately rearward, and a part of the rear extends outward and further extends rearward. A seat 22a is formed, and a second engaging pin 23 is provided on the seat 22a so as to protrude outward. Further, a fork part 24 protruding downward is formed at a lower part of a rear part of the second lens frame 22, and a cut part is formed in the fork part 24. The outer shape of the second lens frame 22 is shaped to be accommodated in the first lens frame 12.

The third lens group 31 is held by a third lens frame 32 together with a shutter unit 33. The third lens frame 32 is provided with a third engagement pin 34 projecting outward. A fork 35 protruding downward is formed below the third lens frame 32, and a cut portion is formed in the fork 35.

The fourth lens group 41 is held by a fourth lens frame 42, and the fourth lens frame 42 is provided with a fourth engagement pin 43 projecting outward. Also, the fourth lens frame 42
A fork portion 44 projecting downward is formed at a lower portion of the fork portion 44, and a cut portion is formed in the fork portion 44. The notches formed in the forks 14, 24, 35, and 44 are located at positions overlapping each other in a direction parallel to the optical axis.

These lens frames 12, 22, 32, 42 are fixed frames.
50 is slidably accommodated in the optical axis direction.
A guide rod 51 supported with the direction parallel to the optical axis as the longitudinal direction before and after
The notches of 14, 24, 35 and 44 are engaged to guide the sliding of the respective lens frames 12, 22, 32 and 42. The fifth lens group 48 is fixed to the rear end of the fixed frame 50.

As shown in FIG. 2, above the fixed frame 50,
A first cam cylinder 52 and a second cam cylinder 53 are provided rotatably supported on the left and right sides of the optical axis. These cam cylinders 52,
Gear portions 52a, 53a are formed at the rear end of each of the 53, and a transmission gear 54 meshes with the gear portions 52a, 53a. A drive motor 55 is provided on the ceiling surface of the fixed frame 50, and its output rotation is appropriately reduced and transmitted to the transmission gear 54. Therefore, the rotation of the driving motor 55 is transmitted to the first cam cylinder 52 and the second cam cylinder 53 via the transmission gear 54.
And the cam cylinders 52 and 53 rotate around an axis parallel to the optical axis. Instead of the driving motor 55, an operation knob or the like may be provided to be exposed outside the fixed frame 50, and the transmission gear 54 may be rotated by operating the operation knob.

FIGS. 5 and 6 show the first cam cylinder 52, respectively.
FIG. 7 is a development view of a second cam cylinder 53. The first cam cylinder 52 has the first
A first cam groove 61 and a third cam groove 63 as a seed transmission means are formed, and a second cam groove 62 and a fourth cam groove 64 as a second transmission means are formed in the second cam cylinder 53. Is formed.

The first cam groove 61 and the third
As shown in FIG. 5, the cam groove 63 includes drive cam portions 61a, 63a each having a linear cam curve portion extending in a direction appropriately inclined from the circumferential direction of the first cam cylinder 52, and drive cam portions 61a, Dead zone portions 61b, 63b extending in the circumferential direction continuously to each of 63a
And is formed from The first cam groove 61 is connected to the first engagement pin 13 provided on the first lens frame 12, and the third cam groove 63 is connected to the third engagement pin 34 provided on the third lens frame 32. Is linked. Therefore, when the first cam barrel 52 rotates, the first lens group 11 and the third lens group 31 are guided by the first cam groove 61 and the third cam groove 63, respectively, and advance and retreat in the optical axis direction.

The second cam groove 62 serving as the second type transmission means and the fourth
As shown in FIG. 6, the cam grooves 64 include drive cam portions 62a and 64a, which are linear cam curved portions extending in a direction appropriately inclined from the circumferential direction of the second cam cylinder 53, and drive cam portions 62a and 62a. The guide cams 62b and 64b are formed in appropriate shapes so as to be continuous with each of the guides 64a and to perform the operation described later. And
The second cam groove 62 is connected to the second engagement pin 23 provided on the second lens frame 22, and the fourth cam groove 64 is connected to the fourth lens frame
The fourth engagement pin 43 provided at 42 is connected. Therefore, when the second cam barrel 53 rotates, the second group lens 21 and the fourth
The group lens 41 is guided by the second cam groove 62 and the fourth cam groove 64, respectively, and advances and retreats in the optical axis direction. This second group lens 21
The zoom lens apparatus is changed in magnification by the reciprocation of the zoom lens device and the fourth lens group 41.
The cam curve of 62 and the fourth cam groove 64 is formed in a shape in which the lens group moves in the optical axis direction while maintaining a predetermined optical relationship.

As described above, each of the lens frames 12, 22, 32, and 42 has a corresponding one of the fork portions 14, 2 as described above.
The notches of 4, 35 and 44 are engaged with the guide rod 51 to guide the sliding. Further, as shown in FIG. 2, through holes are formed in the respective lens frames 12, 22, 32 and 42. Guide wings 12b, 22b, 32b, 42b are formed, and guide rods 56a, 56b, 56c, 56 provided on the fixed frame 50 in parallel with the optical axis.
d is guided through each of these guide wings 12b, 22b, 32b, 42b.

FIGS. 1 to 6 of the present invention constructed as described above.
The operation of the embodiment shown in FIG.

FIG. 1 shows the respective lens groups 11 and 11 in storage positions where the zoom lens apparatus cannot be used for photographing.
This shows a state in which 21, 31, and 41 are located, and the lens groups 11, 21, 31, and 41 are in the closest state. At this time, the first engagement pin 13 of the first lens frame 12 is located at the end of the drive cam portion 61a of the first cam groove 61, and the third engagement pin 34 of the third lens frame 32 is located at the end of the third cam groove 63. At the end of the driving cam portion 63a, the second engaging pin 23 of the second lens frame 22 is connected to the driving cam portion of the second cam groove 62.
The fourth engagement pin 43 of the fourth lens frame 42 is
The cam groove 64 is located at the end of the drive cam portion 64a. In this state, when the drive motor 55 is operated by operating a switch button or the like (not shown), the output rotation is transmitted to the first cam cylinder 52 and the second cam cylinder 53 via the transmission gear 54, and these cam cylinders 52 and 53 rotate.

When the cam barrels 52 and 53 rotate, the first lens frame
Reference numeral 12 denotes a driving cam portion 61a of the first cam groove 61,
Is the driving cam portion 62a of the second cam groove 62, the third lens frame 32 is the driving cam portion 63a of the third cam groove 63, and the fourth lens frame 42 is the driving cam groove 64a of the fourth cam groove 64. Guided and moved in the direction of the optical axis, as shown in FIG.
31 and 41 are the photographing positions and are located on the telephoto side. In this state, the first group lens 11 is located so as to protrude forward from the front end of the fixed frame 50, and the distance between the first group lens 11 and the fifth group lens 48 is required for this zoom lens device. Thus, the zoom lens device can be brought into a state where it can be used for photographing on the telephoto side.

Further, when the drive motor 55 is operated to rotate the cam barrels 52 and 53, a zooming operation from the telephoto side to the wide-angle side is performed. At this time, the first lens frame 12 is in the dead zone 61b, and the third lens frame 32 is in the dead zone 63b.
Therefore, even when the first cam barrel 52 rotates, the positions of the first lens group 11 and the third lens group 31 on the optical axis are not changed. On the other hand, the second group lens 21 is guided by the guide cam portion 62b of the second cam groove 62, and the fourth group lens 41 is guided by the guide cam portion 64b of the fourth cam groove 64 to maintain a predetermined optical relationship. Move on the optical axis. FIG. 3 shows a state in which the second lens group 21 has been moved to the wide-angle side.
Moves from the front end of the fixed frame 50 to the forefront, and is located close to the first group lens 11.

Each lens of this zoom lens device
In order to move 11, 21, 31, and 41 from the photographing position to the storage position, the drive motor 55 is rotated in a direction opposite to the above-described direction. As a result, the cam barrels 52, 53 rotate in opposite directions, so that the respective lens frames 12, 22, 32, 42 are guided by the respective cam grooves 61, 62, 63, 64 and move on the optical axis. The first to fourth lens units 11, 2 are moved by being guided by the drive cam units 61a, 62a, 63a, 64a.
1, 31, and 41 are changed from the state shown in FIG. 4 to the state shown in FIG. 1, and are located at the storage positions. For this reason, this zoom lens device cannot be used for photographing, and the entire length becomes the entire length of the fixed frame 50, so that the zoom lens device is not bulky for carrying or storing.

Next, the embodiment shown in FIGS. 7 to 12 will be described. 1 to 6 show a structure in which the present invention is mounted on a so-called mechanical correction type zoom lens device, whereas FIGS. 7 to 12 show a structure of a so-called optical correction type zoom lens device. This shows the structure when implemented. Further, in this embodiment, the same parts as those in the embodiment shown in FIGS.
The description is omitted. Also in this embodiment, the first lens group 11, the third lens group 31, and the fifth lens group 48 are lenses that do not move at the time of zooming.
The lens 21 and the fourth group lens 41 are lenses that move on the optical axis during zooming. The second lens group 21 has a second lens frame 22
The second engagement pin 23 is engaged with the second cam groove 72 of the second cam cylinder 71 shown in FIG. This second cam groove 72 is
A driving cam portion 72a corresponding to the driving cam portion 62a of the cam groove 62
And a guide cam portion 72b formed of a straight cam curve which is continuous with the driving cam portion 72a and extends in a direction appropriately inclined with respect to the circumferential direction of the second cam cylinder 71. A gear 71 a is formed at the rear end of the second cam cylinder 71, and the gear 71 a meshes with the transmission gear 54.

The fourth lens group holding the fourth lens group 41
As shown in FIGS. 8 and 9, the lens frame 74 has a pair of holding arms 74 a and 74 b extending laterally and projecting therefrom.
A female screw portion is formed on an opposing surface of one or both distal ends of the holding arms 74a and 74b. On the other hand, a pair of brackets 75 projecting inward from the side surfaces of the fixed frame 50 are provided with a correction motor 76, and an output shaft 76a is formed with a male screw portion, and the output shaft 76a is 74a,
The female threads of the holding arms 74a, 74b and the male threads of the output shaft 76a are screwed together. For this reason, when the correction motor 76 operates, the fourth group lens 41 moves back and forth in the optical axis direction. That is, the first to third lens units 11, 21, 31
The cam grooves 61, 72, 63 are respectively driven by the rotation of the first cam cylinder 52 and the second cam cylinder 71 by the rotation of the drive motor 55.
Is moved between the storage position and the photographing position and for zooming, and the fourth group lens 41 is moved by the correction motor 76.
Is operated to move between the storage position and the photographing position and for zooming. Also, the fourth lens frame
A fork 74c protruding downward is formed at a lower portion of the 74, and a notch is formed in the fork 74c.

The zoom lens device according to the embodiment shown in FIGS. 7 to 12 is also accommodated in the fixed frame 50 as shown in FIG. 7 when the lenses 11, 21, 31, and 41 are in the storage positions. 9 and 10, the first group lens 11 projects from the fixed frame 50 and is positioned at the forefront, as shown in FIGS. 9 and 10. The camera is stopped at the shooting position. Then, the second group lens 21
And the fourth group lens 41 are driven to change the magnification while maintaining a predetermined optical relationship.

In the embodiment described above, the structure including the two cam barrels 52 and 53 (71) has been described. However, the number of cam barrels can be changed according to the number of lens groups to be driven. it can. In the case of a structure in which a large number of cam cylinders are driven, these cam cylinders are arranged on an arc centered on the optical axis outside the advancing / retreating area of the photographing lens, and the transmission gear is set to each cam cylinder. The gear may be an annular gear that meshes with the gear portion formed at this time, and the output rotation of the drive motor may be transmitted to the transmission gear. In addition, if the annular transmission gear meshes with the gear portions of at least three cam cylinders, it can be rotatably supported without providing a separate support mechanism. Further, the annular transmission gear may be either an external gear or an internal gear.

[0045]

As described above, according to the zoom lens apparatus according to the first aspect of the present invention, when not used for photographing, the entire length can be reduced by moving the lens group to the storage position. It is the shortest and does not bulk up when carrying or storing. In the case of photographing, an in-focus type zoom lens device can be obtained by moving the lens position to the photographing position. Since the inner focus method can be adopted, the magnification can be increased.

According to the zoom lens apparatus of the second aspect of the present invention, the total length of the fixed frame can be restricted as the total length of the lens group in the storage position, and when the lens group is in the photographing position, By projecting the frontmost lens group from the fixed frame, the overall length can be increased and the movement distance of the lens group can be increased, so that a zoom lens device having a desired magnification can be designed.

According to the zoom lens device of the third aspect of the present invention, the predetermined lens group is divided into the first type transmitting means and the second type transmitting means.
By connecting to any one of the seed transmitting means, the movement between the storage position and the photographing position and the zooming movement can be continuously performed. Therefore, it can be operated by a single drive source.

According to the zoom lens apparatus of the fourth aspect, an operating force is obtained by operating a single part, and the lens group is moved between the storage position and the photographing position. In addition, a zooming operation can be performed. In the case of using a structure using the power of a motor, the motor can be driven by one motor.

According to the zoom lens apparatus of the fifth aspect, for example, the power of the motor is used to move the lens group between the retracted position and the photographing position, and the variable magnification drive is performed. Lens group to perform sufficient functions as a zoom lens device, such as a structure in which zooming is performed manually, and a structure in which a lens group for correction is moved by one motor and another lens group is moved by another motor. The transmission mechanism for driving the motor can be changed.

According to the zoom lens apparatus of the present invention, the lens group can be easily moved between the storage position and the photographing position by one cam groove or the like, and During zooming, the lens group can be easily stopped at a fixed position.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a right side surface of an embodiment of a zoom lens device according to the present invention, with a part thereof cut away, showing a state where a lens group is in a storage position.

FIG. 2 is a front view showing one embodiment of the zoom lens device according to the present invention, and is partially cut away.

FIG. 3 is a partially cut-away cross-sectional view of a right side surface of one embodiment of the zoom lens apparatus according to the present invention, showing a state where the lens group is in a photographing position and is on a wide angle side. I have.

FIG. 4 is a partially cutaway cross-sectional view showing a right side surface of one embodiment of the zoom lens device according to the present invention, showing a state where the lens group is at the photographing position and on the telephoto side. I have.

FIG. 5 is a schematic development view of a cam barrel in which a first type transmission means is formed, showing one embodiment of a zoom lens device according to the present invention.

FIG. 6 shows one embodiment of the zoom lens device according to the present invention, and is a schematic development view of a cam cylinder provided with a second type transmission means.

FIG. 7 is a cross-sectional view, partially cut away, of a right side surface of another embodiment of the zoom lens device according to the present invention, showing a state where a lens group is in a retracted position.

FIG. 8 is a front view showing another embodiment of the zoom lens device according to the present invention, which is partially cut away.

FIG. 9 is a cross-sectional view, partially cut away, showing a right side surface of another embodiment of the zoom lens device according to the present invention, showing a state in which the lens group is in a photographing position and is on a wide angle side. I have.

FIG. 10 is a cross-sectional view, partially cut away, of a right side surface of another embodiment of the zoom lens device according to the present invention, showing a state where the lens group is at the photographing position and on the telephoto side. I have.

FIG. 11 shows another embodiment of the zoom lens device according to the present invention, and is a schematic development view of a cam barrel having a first-type transmission unit formed thereon.

FIG. 12 shows another embodiment of the zoom lens device according to the present invention, and is a schematic development view of a cam cylinder having a second type transmission means.

FIG. 13 is a schematic cross-sectional view showing a two-unit zoom mounted on the camera, showing a state where the lens unit is on the wide-angle side.

FIG. 14 is a schematic sectional view showing a two-unit zoom mounted on the camera, showing a state where the lens unit is on the telephoto side.

[Explanation of symbols]

 11 First group lens 12 First lens frame 13 First engagement pin 21 Second group lens 22 Second lens frame 23 Second engagement pin 31 Third group lens 32 Third lens frame 34 Third engagement pin 41 Fourth group lens 42 Fourth lens frame 43 Fourth engagement pin 48 Fifth group lens 50 Fixed frame 52 First cam cylinder 53 Second cam cylinder 54 Transmission gear 55 Driving motor 61 First cam groove 61a Driving cam (cam Curved portion 61b Dead zone portion 62 Second cam groove 62a Drive cam portion 62b Guide cam portion 63 Third cam groove 63a Drive cam portion (cam curved portion) 63b Dead zone portion 64 Fourth cam groove 64a Drive cam portion 64b Guide cam portion 71 Second cam cylinder 72 Second cam groove 72a Driving cam part 72b Guide cam part 74 Fourth lens frame 76 Correction motor

Claims (6)

[Claims] 1. An inner focusing system comprising three or more lens groups, wherein a predetermined moving lens group located behind the foremost first lens group located on the subject side is moved in the optical axis direction to focus. In the zoom lens device according to the above, the lens group is moved by a given operation force between a storage position where the respective lens groups are located close to each other and cannot be used for shooting, and a shooting position where the lens group can be used for shooting. The movable lens group is movable in the optical axis direction with
A zoom lens device wherein a predetermined optical relationship is maintained and the magnification is changed so as to be movable in an optical axis direction. 2. An in-focus system comprising three or more lens groups, wherein a predetermined moving lens group located behind the foremost first lens group located on the subject side is moved in the optical axis direction to focus. In the zoom lens device of (1), each of the lens groups is held in a predetermined lens frame, the lens frame is slidably connected to the fixed frame in the optical axis direction, and the lens group is moved by the applied operating force. In the optical axis direction between a storage position where the lens groups are located close to each other and cannot be used for shooting, and a shooting position where the lens groups can be used for shooting. The first lens group is slid to a position protruding from the fixed frame to maintain the position, and the predetermined moving lens group is maintained in a predetermined optical relationship to be movable in the optical axis direction. Double While in the retracted position, the zoom lens system, characterized in that all of said lens frame is accommodated in the fixed frame. 3. A first type transmitting means for transmitting an operating force to a lens group maintained at a fixed position during zooming, and a second type transmitting an operating force to a lens group moving in the optical axis direction during zooming. A transmission unit, wherein the first type transmission unit moves the lens group connected to the first type transmission unit between the storage position and the photographing position by the input operation force, and moves the lens group to the photographing position. In a certain state, the operation force is not transmitted to the lens group, and the second type transmission unit moves the lens group connected to the second type transmission unit by the input operation force to the storage position and the shooting position. And moving the lens group while maintaining a predetermined optical relationship while transmitting the operating force to the lens group in a state at the time of photographing. Item 3. The zoom lens device according to any one of items 2. . 4. The zoom lens device according to claim 3, wherein the operation force is applied from a single part. 5. The zoom lens device according to claim 3, wherein the operation force is applied from a plurality of parts. 6. The first-type transmission means and the second-type transmission means are formed by cam means, and the first-type transmission means includes a lens group connected to the first-type transmission means at a storage position and a photographing position. The zoom lens device according to any one of claims 3 to 5, wherein a cam curve portion that moves between the hour position and a dead zone portion that does not transmit an operating force to the lens group is formed.