JP2929480B2 - Zoom camera - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom camera, and more particularly, to a zoom camera which performs zooming by moving a plurality of lens units including a focusing lens unit in the direction of an optical axis.

[0002]

2. Description of the Related Art A conventional zoom camera is provided with a zooming mechanism and a zoom driving source dedicated to zooming, and a focusing mechanism and a focusing drive source dedicated to focusing for focusing. That is, regarding the driving of the focusing lens group in this type of zoom camera, the respective driving mechanisms for zooming and focusing are configured to overlap. Therefore, if an auto-focus configuration is used with the electric zoom,
The driving sources (motors) are also duplicated, so that the camera becomes large, the number of parts increases, and the cost increases.

[0003] Japanese Patent Laid-Open No. 1-92708 discloses a zoom mechanism of a zoom lens which can perform both zooming and focusing using one driving source.
That is, the driving force from one motor is used for both zooming and focusing using a differential gear mechanism and an electromagnetic plunger.

[0004]

However, in the technical means disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 1-92708, an electromagnetic plunger or a differential gear mechanism is used for switching between zooming and focusing. As the score increases, the space increases accordingly.

SUMMARY OF THE INVENTION An object of the present invention is to provide a low cost zoom camera which solves the above-mentioned problems, enables zooming and focusing by using one drive source, and has a small number of parts.

[0006]

Means and Functions for Solving the Problems The first aspect of the present invention is as follows .
The zoom camera, driven in the zoom camera having two or more lens groups, the zoom driving ring for driving a particular lens group, disposed adjacent to the zoom driving ring, certain other lens group A focus and zoom drive ring, a drive source for rotating the focus and zoom drive ring in the forward and reverse directions, and a focus and zoom drive ring formed at an opposing portion of the zoom and focus and zoom drive ring. A clutch means comprising an engaging portion for pressing and rotating the zoom driving ring in accordance with the rotation of the zoom driving ring and a non-conveying portion not for pressing and rotating, and focusing and zooming in the convey portion. The focus operation is performed by rotating the drive ring, and the zoom operation is performed by the interlocking rotation of the focus and zoom drive ring and the zoom drive ring by the engagement portion. The second zoom camera of the present invention
A first drive ring for driving the first lens group and another specific lens
The second drive ring for driving the lens group and the first drive ring
A drive source for rotating in the opposite direction and a rotation of the first drive source
Driving force for rotating the second drive ring in conjunction with
Rotation of the transmission unit and the first drive ring for generating
Transmitting the driving force from the first driving ring to the second driving ring;
And there is no empty feeding portion, and the rotation of the first drive ring is
Zooming drive and focusing drive of each lens group
And clutch means for switching between
I do. The third zoom camera according to the present invention includes the second zoom camera.
In the camera, the transmission unit is provided by a first drive ring.
The driving force is transmitted by pressing and rotating the second drive ring.
Characterized by reaching. Fourth zoom camera of the present invention
Represents the first drive in the second zoom camera;
The ring and the second drive ring are coaxially supported, and the
Latch means is provided between the first drive ring and the second drive ring.
It is characterized by being provided at the opposite end. Departure
Ming's fifth zoom camera is similar to the second zoom camera.
Here, the first drive ring and the second drive ring are mutually
It is supported on separate support shafts and
The reach includes gear means. The present invention
The sixth zoom camera is similar to the second zoom camera described above.
The first drive ring and the second drive ring coaxially overlap.
It is characterized by being supported. Seventh embodiment of the present invention
The zoom camera according to the second zoom camera,
The first drive ring is used for focusing and zooming.
It is a drive ring for focus and zoom to be driven.
The drive ring 2 is a zoom drive ring that is driven during zooming.
It is characterized by being.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings. FIGS. 1 and 2 are a perspective view and a sectional view, respectively, showing the structure of a first embodiment in which the present invention is applied to a two-unit zoom lens zoom camera. This zoom camera has a viewfinder in addition to a photographing lens (this zoom lens). Separately. It also has a zoom button so that zooming can be arbitrarily performed while the main switch is turned on. When the release button is pressed, focusing is performed. When the main switch is turned off, the zoom lens is reset to the initial state.

1 and 2, a first group frame 1 holding a first group lens 1a and a second group frame 2 holding a second group lens 2a.
Is a drive ring for zoom (hereinafter, referred to as Z cam) fitted to a cam support shaft 5 fixed to the camera body 7, a drive ring for focus and zoom (hereinafter, referred to as ZF cam).
4 and a rotation stopper shaft 6 also fixed to the camera body 7, are supported movably in the optical axis direction and are prevented from rotating.

Above the first group frame 1 in the drawing, a support portion 1b having a columnar convex portion 1c fitted into a spiral cam groove 3a provided on the outer peripheral surface of the Z cam 3 is provided. In the lower part of the figure, a U-shaped notch 1d for preventing rotation that engages with the rotation stop shaft 6 is provided.
A contractible first-group frame spring 11 is provided between the camera body 7 and the first-group frame 1 and the Z cam 3 so that the cam joint surface between the first-group frame 1 and the Z cam 3 is made one-sided.

Above the second group frame 2 in the drawing, a support portion 2b having a columnar convex portion 2c fitted into a spiral cam groove 4a provided on the outer peripheral surface of the ZF cam 4 is provided.
In the lower part of the figure, a U-shaped notch 2d for preventing rotation which engages with the rotation stopper shaft 6 is provided. An elastic second-group frame spring 12 is provided between the camera body 7 and the second-group frame 2 and the ZF cam 4 so that the cam joint surface of the second-group frame 2 and the ZF cam 4 is made one-sided. The second group frame 2 is integrally formed with a flat rib 2e for detecting a wide end which is a start position, that is, a reset position, and the rib when the second group frame 2 comes to the reset position. PI (photo interrupter) 10 at the position corresponding to 2e
Are arranged.

A gear 4c is integrally formed on the mount-side end surface of the ZF cam 4 and meshes with a pinion 8a fixed to an output shaft of a rotary drive source 8 composed of a motor and the like fixed to the camera body 7. . The pinion 8a is integrally provided with a slit plate 8b having a large number of openings provided at equal intervals, and a PI is provided at a position sandwiching the slit plate 8b.
9 is fixed.

The above-mentioned opposed portion of the Z cam 3 and the ZF cam 4 includes an engaging portion for pressing and rotating the Z cam 3 in accordance with the rotation of the ZF cam 4 and an idle feeding portion for not pressing and rotating. Clutch means is formed. FIG. 3 (a), (b), (c)
Is a cross-sectional view of the clutch means at the facing portion. The ZF cam 4 is provided with a partial arc-shaped protrusion 4b, and the Z cam 3 is provided with a partial arc-shaped protrusion 3b having a larger arc angle than the protrusion 4b. .

In the tele- side drive, as shown in FIG. 3A, the tele-side drive end face 4bT of the protrusion 4b is moved to the tele-side of the protrusion 3b.
FIG. 3 (c) shows the state of contact with the driving end face 3bT when driving on the wide side .
As shown in the wide side drive end face 4bW of the projecting portion 4b comes into contact with the wide side drive end face 3bW protrusions 3b, the engaging portion is formed by these. Further, at the time of focusing, as shown in FIG.
In the drawing, the empty transport area shown by a white background is moved. Then, the focus operation by the rotation of the ZF cam 4 is performed in the state shown in FIG. 3B, and the zooming is performed by the interlocking rotation of the ZF cam 4 and the ZF cam 3 in the states shown in FIGS. 3A and 3C. Each operation is performed.

FIGS. 4 to 6 are development views of the Z cam 3 and the ZF cam 4, respectively.
4a is like a curve L1 and straight lines L2 and L5. That is, since the ZF cam 4 also functions as a focusing cam, the ZF cam 4 has a linear cam groove so that the lens can be easily extended and retracted. The operation of the first embodiment will be described with reference to FIGS.

When the power switch (not shown) of this zoom camera is turned off, both the first group frame and the second group frame 2 are at the reset position on the wide side, so the rib 2e of the second group frame 2
Enters the gap of the PI 10 to block the optical path of the PI 10, thereby turning off the PI 10. At this time, the partially arc-shaped protruding portion 3b of the Z cam 3 and Z
The partially arc-shaped projection 4b of the F cam 4 is at a relative position shown in FIG.

<< 1 >> In this state, the case where the power switch of the camera is turned on and shooting is performed at the wide end without pressing the tele side zooming button (not shown) will be described with reference to the diagram of FIG. In this case, the first group frame 1 does not move while remaining at the point P1 in the figure, and only the second group frame 2 moves from the point P2 to the point P as described later.
Move to 3. The movement amount α of the second group frame 2 from the straight line L2 to L5 in FIG. 4 is the arc from the tele-side driving end face 3bT to the wide-side driving end face 3bW of the partial arc-shaped projection 3b of the Z cam 3 in FIG. Corresponds to a corner.

When the release button is pressed, distance measurement is performed first. In order to extend the lens to the in-focus position based on the distance measurement result, the rotation drive source 8 rotates in the CW direction.
Then, the pinion 8a fixed to the output shaft and the slit plate 8b rotate integrally in the CW direction. Accordingly, in response to the rotation of the slit plate 8b, the PI 9 is driven by the slit plate 8b.
A pulse is generated each time the slit passes.

When the pinion 8a rotates in the CW direction, the ZF cam 4 engaged with the pinion 8a rotates in the CCW direction. ZF
The second group frame support portion 2b is fitted on the outer peripheral surface of the cam 4, and
Since the cylindrical convex portion of the second group frame 2 is fitted in the cam groove 4a of the F cam 4, when the ZF cam 4 rotates in the CCW direction,
The second group frame 2 is extended from the point P2. If this lens extension continues, the rib 2e of the second group frame 2 moves away from the PI 10, and the PI 10 turns on at a certain time point t1. From this point, the pulse count of PI9 is started. By the way, since a focus amount based on the distance measurement data and the focal length is converted into a pulse of PI9 and stored in advance by a control device (not shown) having a built-in CPU or the like, the PI
From the start of the pulse counting of 9, the rotation of the rotary drive source 8 is stopped at a point P3 driven by the converted pulse. Thereby, the first and second group frames are stopped at the position where focusing at the wide end is performed.

The above operation will be described with reference to FIG. 3. Before the rotation drive source 8 rotates, as shown in FIG.
And 4bW. 3b when the driving source 8 rotates
W and 4bW are separated, only ZF cam 4 is rotated and 2 group frame
Only 2 is driven. The focus amount in this case is set to be smaller than the rotation angle α (horizontal distance from the straight line L2 to L5 in FIG. 4) at which the ZF cam 4 rotates from the position shown in FIG. 3C to the position shown in FIG. Therefore, even in the closest shooting at the wide-angle end, as shown in FIG.
It is unlikely that the second group frame 2 is extended until 4bT is applied.

<< 2 >> Next, photographing after zooming to the telephoto side when the power switch of the camera is turned on and a telephoto zooming button (not shown) is pressed will be described with reference to FIG. When the drive source 8 rotates in the CW direction, first, the second group frame 2
Is fed from the point P2 in the same manner as described in <1>. The second group frame 2 is advanced by the movement amount α (step S1),
When the tele-side driving end face 4bT of the projection 4b of the ZF cam 4 hits the tele-side driving end face 3bT of the projection 3b of the Z cam 3,
At this time point P4, the Z cam 3 also starts to rotate in the same manner as the ZF cam 4. Then, the first group frame 1 is guided out of the point P1 and the second group frame 2 is guided out of the point P4 to the respective cam grooves 3a, 4a (Step S2).

Next, when the zooming button is released (point P
5) The rotation of the drive source 8 stops. So the camera, P
P from when I10 is turned on to when drive source 8 is stopped.
The focal length is calculated from the count of I9.

Here, when the release button is pressed, distance measurement is performed, and a focus amount based on the distance measurement data and the focal length is converted into a pulse. Next, the drive source 8 rotates in the CCW direction, and the ZF cam 4 rotates in the CW direction.
Is repeated (step S3). When the drive source 8 starts rotating, the PI newly starts counting pulses, and stops the rotation of the drive source 8 at a point P6 where the pulses corresponding to the focus amount are counted. As a result, only the second group frame 2 stops at the position P6 where the focus amount has been advanced.

The focus amount at this time is set smaller than the rotation angle α at which the ZF cam 4 rotates from the position shown in FIG. 3A to the position shown in FIG. Therefore, at the zooming position
Even when photographing the subject at the position, the second group frame is not moved until 3bW and 4bW are applied, as shown in FIG. 3C.

The camera calculates and stores the current positions of the first group frame 1 and the second group frame 2 until the power switch of the camera is turned off. Therefore, when the release is performed and the distance measurement data changes before the next zooming button is pressed, the number of pulses to be driven in which direction from the current second group frame position is converted, and the drive source 8 is correspondingly converted. Is driven to rotate.

When the telephoto zooming button is continuously pressed, the drive source 8 is driven to rotate in the CW direction until a preset tele end pulse, at which point the rotation of the drive source 8 is stopped.

<< 3 >> Shooting after the wide-side zoom button is pressed when zooming is not already at the wide end is performed as shown in FIG.
This will be described below. When the driving source 8 is rotated CCW, PI
9 starts pulse counting. In this case, immediately before the drive source 8 is rotated in the CCW direction, the state shown in FIG. 3A (the state in which the tele side zoom button is pressed and the release is not performed before the wide side zoom button is pressed) or the state shown in FIG. ) (Released and focused just before the wide-side zoom button is pressed). Here on the camera, the wide-side drive end face 4bW of ZF cam 4 is calculated the number of pulses of PI9 required until get applied to the wide side drive end face 3bW of Z cam 3.

When the drive source 8 rotates CCW, first, only the ZF cam 4 rotates CW, and the second group frame 2 starts to be retracted.
Then, when the 4 bW hits the 3 bW, the Z cam 3 also starts to rotate in the same manner as the ZF cam 4, and both the second group frame and the first group frame are guided into the respective cam grooves, and are reciprocated.

Then, when the wide zoom button is released,
The drive source 8 stops rotating, and the focal length at the current lens position is determined based on the number of pulses of the PI 9. On the other hand, if the PI 10 is turned off before the wide zoom button is released, the rotation of the drive source 8 is stopped at that point.

Here, when the release button is pressed, the distance measurement is performed, and the focus amount is converted into pulses based on the distance measurement data and the focal length data. Then, since the drive source 8 rotates in the CW direction, the ZF cam 4 rotates in the CCW direction. When the drive source 8 starts rotating, the PI 9 starts pulse counting, and stops the rotation of the drive source 8 when the pulses corresponding to the focus amount have been driven. This means that the lens is set at the position where focus is achieved. Of course, at this time, the setting can be made even at the time of the closest shooting before 4bT hits 3bT.

The second group frame spring 12 provided between the second group frame 2 and the camera body 7 is connected to the camera body 7 and the ZF cam 4.
And between the ZF cam 4 and the second group frame 2 are removed. The first frame spring 11 between the first frame 1 and the main body 7 is provided between the ZF cam 4 and the Z cam 3.
And to remove backlash existing between the Z cam 3 and the first group frame 1. This improves the precision of zooming and focusing.

According to the first embodiment, a low-cost zoom camera having a small number of components and capable of performing both zooming and focusing with one rotary drive source 8 can be constructed.

Next, a modification of the first embodiment will be described with reference to FIGS.
This will be described below. In this modification, instead of the ribs 2e and PI10 provided on the second group frame 2 in the first embodiment,
As shown in FIG. 7, the second group frame 2 has a partially arc-shaped projection 2f.
And a wedge-shaped protrusion 4d is formed integrally with the ZF cam 4.

Then, when the ZF cam 4 rotates in the CW direction and the second group frame 2 is retracted, the protrusion 4d is moved to the protrusion 2f.
, Whereby the rotation of the ZF cam 4 is stopped. The position of the second group frame in the stopped state is set to a position that is further depressed from the ∞ focus position at the wide end. The protrusion amounts of the protrusion 4d and the protrusion 2f are as follows.
ZF cam 4 is 1 in the CCW direction from the position where they touch each other.
When rotated, 2f and 4d are protrusion amounts that do not interfere. Except for this point, the first motor including the clutch means
There is no difference from the configuration of the embodiment.

The operation of the present modified example will be described. When the first and second group frames are on the wide side (the power switch of the camera is off), the power switch (in this case, at the position of FIG. 3C) is turned on and the tele side zoom button is pressed, the drive is performed first. The source 8 is driven to rotate in the CCW direction. Then, the projection 2f and the projection 4d in FIG. 7 abut against each other and the rotation is stopped, whereby the initial position of the ZF cam 4 is determined. In this case, even if the drive source 8 is driven to rotate to CCW, no pulse is generated in the PI 9 because the rotation of the ZF cam 4 stops.

Then, a time after the PI 9 stops generating a pulse is detected, and when this time reaches a preset reset time limiter second, it is determined that the ZF cam 4 has stopped at the initial position, This time, the drive source 8 is driven to rotate in the CW direction. When rotation in the CW direction starts, P
I9 starts pulse counting. When the tele side zoom button is released, the rotation of the drive source 8 is stopped, and the PI
9 converts the focal length from the number of pulses counted.

When the wide-side zoom button is kept pressed and when the power switch of the camera is turned off,
The drive source 8 rotates in the CCW direction, and the PI 9 generates a pulse. When the rotation continues, the first and second group frames are retracted, and when the protrusion 2 f of the second group frame 2 locks the projection 4 d of the ZF cam 4, the rotation of the ZF cam 4 stops. As a result, the rotation of the drive source 8 also stops, so that no pulse is generated in the PI 9. The time from when the pulse is no longer generated in the PI 9 is detected, and when this time reaches a preset reset time limiter second, it is determined that the reset has ended, and the drive source 8 is determined.
Turn off the power to the. The movement of the first and second group frames in this modification is performed as shown in FIG.
The reset position of the second group frame 2 and the contact position of the rotation stopper are point P2. Except for the above, the other operations are the same as those of the first embodiment, and the description thereof will be omitted.

Next, a zoom camera according to a second embodiment of the present invention will be described with reference to FIGS. In the first embodiment, the Z cam 3 and the ZF cam 4 are supported by one cam support shaft 5, whereas in the second embodiment, the Z cam 23 and the ZF cam 24 are separately provided. It is supported by a support shaft. Therefore, the clutch means in the second embodiment is
The Z cam 23 is formed inside a second transmission gear 34 driven from the ZF cam 24.

FIGS. 9 and 10 are a perspective view and a sectional view of the second embodiment, and FIGS. 11 and 12 show a β-β section and a γ-γ section in FIG. 10, respectively. The pinion 28a fixed to the rotation shaft of the drive source 28 meshes with a first transmission gear 33 fitted on the mount-side end surface of the ZF cam 24, and a second transmission gear 34 coaxial with the gear 33. A gear 23 integrally formed on the mount-side end surface of the Z cam 23
It is engaged with c.

As shown in FIG. 11, the ZF cam 24 rotatably supported by the camera body 27 is D-cut so as to rotate in the same direction as the first transmission gear 33. When the ZF cam 24 rotates, the second group lens 22a
Is moved back and forth in the optical axis direction by a cam coupling composed of a spiral cam groove 24a and a cylindrical projection 22c, as in the first embodiment.

Further, separately from the ZF cam 24, the Z cam 23
When the Z cam 23 is rotated, the first group frame 21 holding the first group lens 21a is rotated by the cam coupling comprising the cam groove 23a and the projection 21c. It is moved back and forth in the direction. 26 is a rotation stop shaft, 31 and 32 are backlash preventing springs, and 29 is a PI.
It is.

As shown in FIG. 12, the clutch means for transmitting the rotation of the ZF cam 24 to the Z cam 23 is provided on the semi-circular projection 24b provided on the ZF cam 24 and the second transmission gear 34. And a projection 34a having a partially arcuate shape. The clutch means has exactly the same configuration as that of the first embodiment, and the focus operation is performed in the state shown in the figure. Further, when the ZF cam 24 is further rotated and the tele-side driving end surfaces 24bT and 34aT or the wide-side driving end surfaces 24bW and 34aW respectively come into contact with each other, the ZF cam 24 and the Z cam 23 rotate in conjunction with each other to perform a zoom operation.

FIGS. 13 and 14 are an exploded perspective view and a sectional view of a main part of a zoom camera showing a third embodiment of the present invention. In this third embodiment, a ZF cam ring and a ZF cam are provided on the outer peripheral surface of a fixed frame. The cam ring is slidably fitted to each lens group, and each lens group fitted to the inner peripheral surface of the fixed frame is driven. The clutch means is formed by a notch and a projection provided on a contact surface between the Z cam ring and the ZF cam ring.

In the figure, ZF is attached to the outer peripheral surface of the fixed frame 51.
The cam ring 52 and the Z cam ring 53 are fitted, and the axial movement of the two cam rings 52 and 53 is regulated by the retaining ring 54 and the flange fitted to the tip of the fixed frame 51. .

A first group frame 55 is fitted on the inner peripheral surface of the fixed frame 51, and cam pins 55a are planted at three places obtained by dividing the outer peripheral surface into three equal parts. This fits into both the straight guide groove 51a of the fixed frame 51 and the zooming cam groove 53a of the Z cam ring 53.

Further, a second group frame 56 is also fitted on the inner peripheral surface of the fixed frame 51, and cam pins 56a are planted at three places where the outer peripheral surface is divided into three equal parts. This fits into both the straight guide groove 51a of the fixed frame 51 and the zooming focusing cam groove 52a of the ZF cam ring 52.

A gear 52c is provided on the outer peripheral surface of the ZF cam ring 52.
Are integrally formed and mesh with the transmission gear 57. Power is transmitted to the transmission gear 57 from the same rotary drive source (not shown) as in the above embodiments (including a pulse count unit).

The opposed portion between the ZF cam ring 52 and the Z cam ring 53 has a convex portion 52b and a concave portion 53b wider than the convex portion 52b.
Are provided, thereby forming clutch means.

The operation of the embodiment having the above-described structure will be described below. When the rotation drive source (not shown) rotates forward and the ZF cam ring 52 rotates in the CW direction via the transmission gear 57, 2
The group frame 56 is guided linearly by the linear guide groove 51a of the fixed frame 51, guided to the zooming focusing cam groove 52a of the ZF cam ring 52, and extended out in the optical axis direction. Then, when the convex portion 52b forming the clutch means comes into contact with the concave portion 53b of the Z cam ring 53 and is driven, the first group frame 5
5 is also guided straight by the straight guide groove 51a of the fixed frame 51,
The Z cam ring 53 is guided out of the zooming cam groove 53a and is fed out. When the rotation drive source (not shown) reversely rotates, the ZF cam ring 52 rotates in the CCW direction via the transmission gear 57,
The second group frame 52 is reversed in the above manner. When the clutch means is further rotated and the above-mentioned clutch means is operated, the ZF cam ring 53 is also driven and the first group frame 55 is retracted. The details are the same as those of the above-described embodiments.

FIGS. 15 and 16 are an exploded perspective view and a sectional view of a main part of a zoom camera according to a fourth embodiment of the present invention. The fourth embodiment differs from the third embodiment in that the arrangement of the ZF cam ring and the Z cam ring on the outer peripheral surface of the fixed frame is repeated.

A Z cam ring 62 is rotatably fitted on the outer peripheral surface of the fixed frame 61, and a ZF cam ring 63 is rotatably fitted outside thereof. The axial movement of the two cam rings is restricted by the retaining ring 64 at the tip of the fixed frame 61 and the flange portion of the fixed frame 61.

The first group frame 65 is fitted on the inner peripheral side of the fixed frame 61, and the cam pins 65a are provided at equal intervals on the feet 65b of the first group frame.
It has been planted in several places. This fits into the straight guide groove 61a of the fixed frame 61, and further fits into the zooming cam groove 62a of the Z cam ring 62.

The second group frame 66 has cam pins 66a implanted at equal intervals at three locations on the outer periphery thereof. The cam pins 66a are fitted into the straight guide grooves 61b of the fixed frame 61, and further, the holes 62 of the Z cam ring 62 are formed.
b, it is fitted in the ZF cam groove 63b of the ZF cam ring 63.

A gear 63c is integrally formed on the outer periphery of the ZF cam ring 63, and a gear train (not shown) is engaged. ZF
In the cam ring 63, a convex portion 63a for transmitting rotation to the Z cam ring 62 is engaged with a concave portion 62c of the Z cam ring 62, thereby forming clutch means. And 63a
During the movement of the cam pin 66a in the range of 62c, the cam pin 66a hits the wall of the hole 62b of the Z cam ring 62.

The operation of the present embodiment having the above-described structure is the same as that of the third embodiment, and the description thereof is omitted.

FIG. 17 is a perspective view of a zoom camera showing a fifth embodiment of the present invention. The fifth embodiment is significantly different from the above embodiments in that the present invention is applied to a zoom optical system having a three-group configuration. Since the moving amount of the focusing changes, a mechanism corresponding thereto will be described first.

The first group lens frame 71 holds the first group lens, the second group lens frame 72 holds the second group lens, and the third group lens frame 73 holds the third group lens. Each of the arms 71a, 72 fits in a cam cylinder 74, 75, 76 described later.
a, 73a, and the arm portions 71a, 72a, 73a have cam followers 71c, 72c, 73c, respectively.

Each of the cam barrels 74, 75, 76 for driving the zoom of each lens frame has a cam groove 74a, 75, respectively.
a and 76a. These cam grooves 74a, 75a, 7
6a has cam followers 71c, 72c, 73c respectively.
Are slidingly fitted.

The cam cylinders 74, 75, and 76 are held linearly, and a cam support shaft 80 fitted to each of the cam cylinders is fixed to the camera body.
4, 75, 76 are rotatably supported.

The cam cylinder 74 has a cutout portion 74b and a flat portion 74.
c and 74d are provided respectively. Also, the cam cylinder 7
6 has a notch 76b and flat portions 76c and 76d, respectively. The cam cylinder 75 has projections 75b at both ends thereof.
75c, and the projections correspond to the flat portions 7 of the cam cylinders 74, 76.
The clutch means is constituted by abutting on each of 4c, 74d, 76c, 76d, and the cam cylinders 74, 76 are rotated with the rotation of the cam cylinder 75. Then, each lens group moves in the optical axis direction.

The first lens frame 71 is provided with a rotation stop shaft 71b fixed in parallel with the optical axis, and a groove 72d slidingly fitted with the rotation stop shaft 71b.
Are provided on the second lens group frame 72. A rotation stop shaft 72b is fixed to the second group lens frame 72 in the optical axis direction, and a groove 73d slidingly fitted with the rotation stop shaft 72b is provided in the third group lens frame 73. Further, a groove portion 73e which is slidably fitted to the rotation stopper shaft 81 fixed to the camera body is provided on the third lens group frame 73, so that the respective lens groups do not deviate from each other even by zooming and focusing movements. It has been like that.

The springs 82 and 83 are members for preventing play between the lens groups. Then, the switch 84 provided on the camera body is pressed by the projection 72 e formed on the second lens frame 72. The switch is switched by this pressing, and the initial reset position of the lens group is detected. In this initial reset position, the switch 84
Is off.

A gear 75b is formed on the outer peripheral surface of the cam cylinder 75. The gear 75b is driven by a motor 78, and the cam cylinder 75 rotates via a pinion 78a. The slit plate 78b is a member for transmitting and blocking the light of the photocoupler 79, and detects the lens position by this rotation.

FIG. 18 is a diagram showing the position of each lens unit, and the zoom from tele to wide or from wide to tele is shown.
During focusing, all the units move, and during focusing, only the second lens unit moves within the β region. FIG. 19 is an explanatory view in which the cam cylinder is developed in a plane.

Next, the operation of the fifth embodiment will be described.

First, the focusing operation at the time of widening will be described. FIG. 17 shows the wide state, but the focusing two-group lens is at the initial reset position outside the focusing area. That is, the second lens group is located at point A in FIG. 18, and the projections 75b, 75 of the cam barrel 75 are shown in FIG.
c is at the position indicated by the solid line.

When focusing from this state,
By driving the motor 78, the cam barrel 75 is rotated clockwise (in FIG. 19, the cam barrel 75 is moved downward), and the second group lens frame 72 is extended. Then, since the switch 84 is turned on, the pulses generated by the photocoupler 79 are counted from this point, and the rotation of the cam is continued until the required focal position is reached. At this time, the cam cylinders 74 and 76 do not rotate. That is, the second lens group frame 72 moves from the point A to a position between the points BC in FIG. In FIG. 19, the projection 75 of the cam cylinder 75 is shown.
c and 75b will be fed in the cutouts 76b and 74b. Then, when the required number of pulses are generated, that is, at the time of focusing, the driving of the motor 78 is stopped.

Next, focusing at an arbitrary focal length will be described. Before the motor is driven, it is in the same initial reset state as described above. In order to correspond to the point G in FIG. 18, that is, to focus on a certain subject distance at a certain focal length, the motor 78 is driven to rotate the cam cylinder 75 clockwise. Thereby, the projection 75 of the cam cylinder 75
b and 75c are brought into contact with the flat portion 74d of the cam cylinder 74 and the flat portion 76d of the cam cylinder 76, respectively. From this point, the cam cylinders 74 and 76 also rotate in conjunction with the cam cylinder 75. Referring to FIG. 18, the second lens group frame 72 moves from point A to B → C → D.
To the point (only the cam cylinder 5 rotates during this period),
The cam cylinders 75, 74, 76 rotate together and move from the point D to the point E. Then, only the cam cylinder 75 is rotated counterclockwise to reach the focal point G through the point F.

Referring to FIG. 19, when the cam cylinder 75 continues to move downward in the figure from the initial state of the solid line in the figure, the projections 75b and 75c abut the flat portions 74d and 76d. Then, the cam cylinders 74 and 76 move downward together with the cam cylinder 75, and stop moving when the required focal length is reached. Then, for focus adjustment, only the cam cylinder 75 is moved upward without moving the cam cylinders 74 and 76 to focus.

In the reset operation from the point G to the point A in FIG. 18, only the cam cylinder 75 is first rotated counterclockwise to reach the point I through the point H. At this point I, the cam cylinder 7
5 is reached, the projection 75b of the cam cylinder 75 is
, And the projection 75c of the cam cylinder 75 abuts on the planar part 76c of the cam cylinder 76 (see FIG. 19). Therefore, if the cam cylinder 75 is further rotated counterclockwise from the point I, both the cam cylinders 74 and 76 are also rotated counterclockwise to reach the initial reset position A. At this initial reset position A, the projection 72e of the second lens group
Presses the contact piece of the switch 84, thereby turning off the switch 84, thereby stopping the drive of the motor 78.

It should be noted that the point G in FIG.
In order to move the group lens (to focus on another object distance at another focal length), the cam barrel 75 is moved to CW or CC.
It can be done freely by moving it in the W direction.

According to each of the above-described embodiments, a low-cost mechanism with a small number of components for performing zooming and focusing can be constructed with only one drive source and without requiring any other actuator.

[0072]

As described above, according to the present invention, a zoom drive ring is provided at a portion opposite to the zoom drive ring and the focus / zoom drive ring in accordance with the rotation of the focus / zoom drive ring. A clutch means including an engaging portion for pressing and rotating and a non-pressing and rotating non-feeding portion is provided, and a focus operation is performed by turning a focus and zoom drive ring in the non-pressing portion, and the focusing by the joint portion is performed. Since the zoom operation is performed by the interlocking rotation of the zoom drive ring and the zoom drive ring, zooming and focusing can be performed using one drive source, and the number of parts is small and the cost is remarkably low. The effect is exhibited.

[Brief description of the drawings]

FIG. 1 is a perspective view of a main part of a zoom camera according to a first embodiment of the present invention.

FIG. 2 is a sectional view of the first embodiment.

FIG. 3 is a view for explaining the operation of the clutch means in FIG. 1;

FIG. 4 is a diagram showing the movement of each lens group when taking a picture at the wide end without pressing the tele side zooming button in the first embodiment.

FIG. 5 is a diagram showing the movement of each lens group when the telephoto zoom button is pressed in the first embodiment.

FIG. 6 is a diagram showing the movement of each lens group when the wide-side zoom button is pressed when zooming has not been performed at the wide end in the first embodiment.

FIG. 7 is a perspective view of a main part of a modification of the first embodiment.

FIG. 8 is a diagram showing the movement of each lens group in FIG. 7;

FIG. 9 is a perspective view of a main part of a zoom camera according to a second embodiment of the present invention.

FIG. 10 is a sectional view of FIG. 9;

FIG. 11 is a sectional view taken along the line β-β in FIG. 10;

FIG. 12 is a sectional view taken along the line γ-γ in FIG. 10;

FIG. 13 is an exploded perspective view of a zoom camera showing a third embodiment of the present invention.

FIG. 14 is a sectional view of a main part of the third embodiment.

FIG. 15 is an exploded perspective view of a zoom camera showing a fourth embodiment of the present invention.

FIG. 16 is a sectional view of a main part of the fourth embodiment.

FIG. 17 is an essential part perspective view of a zoom camera showing a fifth embodiment of the present invention.

FIG. 18 is a diagram showing the movement of each lens unit in the fifth embodiment.

FIG. 19 is a development view of each cam ring in FIG. 17;

[Explanation of symbols]

 3... Zoom drive ring 4... Focus and zoom drive ring 3 b, 4 b. Clutch means 8... Drive source

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G02B 7/08 G02B 7/10 G03B 3/10 G03B 5/00

Claims (7)

(57) [Claims] 1. A zoom camera having two or more lens groups, comprising: a zoom drive ring for driving a specific lens group; and a zoom ring disposed adjacent to the zoom drive ring for driving another specific lens group. A driving ring for focusing and zooming, a driving source for rotating the driving ring for focusing and zooming in the forward and reverse directions, and a driving source formed on an opposite portion between the driving ring for zooming and the driving ring for focusing and zooming. And a clutch means comprising an engaging portion for pressing and rotating the zoom driving ring in accordance with the rotation of the zoom driving ring and a non-conveying portion which does not press and rotate, and focusing and zooming in the convey portion. Wherein the focus operation is performed by rotating the drive ring for zooming, and the zoom operation is performed by the interlocking rotation of the drive ring for focus and zoom and the drive ring for zoom by the engagement portion. Camera. 2. A first drive ring for driving a specific lens group.
When, A second drive ring for driving another specific lens group; A drive source for rotating the first drive ring in forward and reverse directions; The second drive ring is moved in conjunction with the rotation of the first drive source.
A transmission unit for generating a driving force for rotating the first and the first parts;
The driving force from the first driving ring even when the driving ring is rotated.
An idle feeding portion that does not transmit to the second drive ring,
Zooming drive of each lens group according to rotation of the first drive ring
Clutch means for switching between dynamic and focusing driving; A zoom camera comprising: 3. The transmission section is driven by a first drive ring to a second drive ring.
The driving force is transmitted by pressing and rotating the drive ring.
The zoom camera according to claim 2, wherein: 4. The first drive ring and the second drive ring are the same.
The clutch is supported on the shaft Means for driving said first drive
Provided at opposite ends of the ring and the second drive ring.
The zoom camera according to claim 2, wherein 5. The first drive ring and the second drive ring are arranged alternately.
Are supported on separate support shafts and the clutch means
Wherein the transmission section includes gear means.
Item 2. The zoom camera according to Item 2. 6. The first drive ring and the second drive ring are the same.
3. The device according to claim 2, wherein the shaft is supported on the shaft.
On-board zoom camera. 7. The focusing device according to claim 1, wherein the first driving ring is provided for focusing and zooming.
Focus and zoom drive ring driven during zooming
And the second drive ring is driven during zooming.
3. The zoom drive ring according to claim 2, wherein the drive ring is a zoom drive ring.
Zoom camera.