JPH0675155A - Zoom lens camera - Google Patents

Abstract

(57) [Abstract] [Purpose] In a camera equipped with a zoom lens for moving a photographing lens by a motor without using a cam frame, the image magnification of a finder optical system is changed in accordance with the zooming. , Keep the image magnification unchanged during focusing. [Composition] Zooming drive and foming by the motor 33.
The input gear 34 meshed with the gear portion 31a of the zoom lens unit 31 which is driven by casking, and the input gear 34
A finder drive mechanism for moving the finder cam plate 37 by the interlocking gears 35 and 36 interlocked with the brake lever 51 is provided to allow the finder cam plate 37 to move during the pressing operation of the zoom button 54, and the input gear 34.
And the interlocking gear 35, and a driving force transmission switching means by means of a friction spring 38 that slips when the break lever 51 is in a braking operation.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a zoom lens camera in which the image magnification of a finder optical system changes according to the focal length of a zoomed photographic lens.

[0002]

2. Description of the Related Art A zoom lens provided in a camera has a cam frame having a long and narrow cam hole along the periphery thereof, and a cam follower protruding into the cam hole fixedly attached to the zoom lens, and is mounted inside the cam frame to form a photographing lens. In many cases, a plurality of moving frames supported by the cam frame are rotationally driven to move the moving frames, and the photographing lens is displaced in the optical axis direction to change the magnification.

However, since such a zoom lens uses a cam frame which requires high accuracy in design and production, it becomes a high-cost product, and therefore a zoom lens which does not use any cam frame is used today. Murens is being developed.

FIG. 6 (A) is a simplified diagram of a zoom lens configured to drive a motor without using a cam frame. As shown in the figure, a first moving frame 13 is provided in the fixed frame 11 so as to move along the optical axis 12.

A shutter mounting frame 14 is fixed to the first moving frame 13, and a taking lens 15 of the front group is mounted on the shutter mounting frame 14. It should be noted that shutter blades are provided on the back side of the shutter mounting frame 14.

The first moving frame 13 is connected to a drive ring 16 and is pushed out by the drive ring 16 and pulled back. That is, the male helicoid screw provided on the outer periphery of the drive ring 16 is screwed into the female helicoid screw on the inner surface of the fixed frame 11, and the drive ring 16 is
It is driven to rotate by the motor 17 and moves in the optical axis direction,
The first moving frame 13 is moved back and forth without rotating.

Inside the first moving frame 13, there is provided a second moving frame 19 to which a taking lens 18 of the rear group is attached. A part of the second moving frame 19 is screwed into a lead screw 20 pivotally supported by the first moving frame 13, and the lead screw 2
When 0 is rotationally driven by the second motor 21 arranged in the shutter mounting frame 14, the second moving frame 19 moves along the optical axis 12.

FIG. 6A shows the zoom lens retracted into the camera. When the main switch is turned on in this collapsed state, the first motor 17 is driven to rotate in one direction. The ring 16 is moved forward while rotating. Therefore, the first moving frame 13 is extended to the shooting position shown in FIG. 6 (B).

When the first moving frame 13 is moved to this photographing position, the detection signal causes the first motor 17 to stop and the second motor 21 to rotate. As a result, the second
The moving frame 19 moves backward as shown in FIG.
Will be in the shooting state.

When photographing in the WIDE state, the first motor 17 is driven to rotate again in accordance with the release and focusing is performed. In other words, the movement of the first moving frame 13 causes both the front lens group 15 and the rear lens group 18 to move together for focusing.

For zooming, the first motor 17 is rotationally driven, the first moving frame 13 and the second moving frame 19 are both fed out, and then the second motor 21 is rotationally driven to the second. Only the moving frame 19 is moved.

For example, at the WIDE position shown in FIG.
When moving, the taking lens 15 of the front group and the taking lens 18 of the rear group move forward together, and in the TELE position, as shown in FIG.
As shown in. After that, the second motor 21 is rotationally driven, and as shown in FIG. 7B, the photographing lens 18 of the rear group moves forward to enter the TELE photographing state.

After zooming in this way, the first mode is set.
Focusing is performed by rotating the motor 17 according to the release, but when distance measurement is performed at a distance closer than the closest distance, the second mode is activated in response to the release operation.
The camera 21 is driven to rotate, and the taking lens 18 of the rear group is displaced to a predetermined position to perform telemacro focusing.

The zoom lens described above was developed by the inventor of the present application, and was issued in 1993 by Japanese Patent Application No. 35801.
No. 5 has already been applied for a patent.

[0015]

SUMMARY OF THE INVENTION According to the present invention, in a camera provided with a zoom lens as described above, the image magnification of a finder optical system configured separately from the taking lens is changed in accordance with zooming, and the finder is used. Zoom that prevents the image magnification of the optical system from changing due to focusing
The purpose is to develop a Murens camera.

[0016]

In order to achieve the above object, in the present invention, the first and second photographing lenses are moved by the first motor, and the second photographing lens is moved by the second motor. After zooming, a lens drive mechanism for focusing by moving the first and second photographing lenses together by the first motor, and a finder optical system composed of a plurality of lenses different from the photographing lens are provided. In a zoom lens camera provided with a finder drive mechanism for changing the image magnification of the finder optical system according to the focal length of the photographic lens zoomed in conjunction with the first motor, the finder drive mechanism comprises: A zoom lens comprising a driving force transmission switching means for transmitting the driving force in association with the zooming operation, or at least interlocking the driving force in conjunction with the focusing operation. To propose a camera.

[0017]

The lens drive mechanism is interlocked with the rotation of the second motor after moving the first and second photographing lenses to a predetermined position in conjunction with the first motor rotated by the zooming operation. Then, zooming is performed by moving only the second taking lens. Further, since the driving force transmission switching means is in the transmission state in association with the zooming operation, the finder drive mechanism interlocks with the rotation of the first motor to zoom the image magnification of the finder optical system. It is changed so as to correspond to the focal length of the taken lens.

When zooming is finished and focusing is performed, the driving force transmission switching means is switched to the non-transmission state and both the first and second photographing lenses are moved by the first motor. Focusing is performed. Therefore, in focusing, the finder drive mechanism is the first.
In order not to transmit the power of the motor to the finder optical system,
The image magnification of the finder optical system does not change.

[0019]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a first embodiment and is a simplified perspective view showing a lens and a driving portion of a finder of a zoom lens camera. In this embodiment, a flash mechanism integrated with the finder optical system is provided.

In this figure, reference numeral 31 denotes a zoom lens unit fixed to the camera body. Inside the zoom lens unit, like the conventional example, there are provided two groups of taking lenses, a second motor and a lens shutter. There is.

In this zoom lens unit 31, the output gear 3 of the interlocking gear train is connected to the gear portion 31a provided outside the lens frame.
2 is engaged with each other, and the front and rear lens groups of the zoom lens unit 31 are moved together by the rotational driving force of the first motor 33.

The input gear 34 meshed with the gear portion 31a of the zoom lens unit 31 is an interlocking gear 35,3.
6 and the linear gear 37a of the finder cam plate 37 constitute an interlocking gear train (finder drive mechanism) for driving the finder optical system.

A friction spring 38 is provided between the input gear 34 and the interlocking gear 35 of the interlocking gear train, and the first spring 3 is provided during the zooming of the friction spring 38.
The driving force from 3 is transmitted to the finder optical system, and the driving force is interrupted by slipping while slipping except during zooming.

That is, the friction spring 38 is inserted in the shaft of the interlocking gear 35, and the input gear 34 is further inserted and snap-fastened by the E ring 39. The friction spring 38 is designed to obtain a constant friction torque.

The finder cam plate 37 has pins 40a, 40 of the finder support frame in the linear cam holes 37b, 37c.
b is plunged in and the movement is restricted in the left-right direction. Also,
The finder cam plate 37 is provided with cam holes 37d and 37e for changing the magnification of the finder and a cam hole 37f for changing the flash irradiation angle.

A cam hole 37 for changing the magnification of the finder
The pins 42a and 43a of the variable power lenses 42 and 43 of the finder unit 41 are projected into the d and 37e, and the flash unit having a xenon discharge tube or a reflecting mirror is provided in the cam hole 37f for changing the flash irradiation angle. The pin 44a of 44 is inserted.

The optical system of the finder unit 41 includes an objective lens 45, variable power lenses 42 and 43, and a right angle prism 4.
6, a mask 47, a prism 48 having three reflecting surfaces, and an eyepiece (not shown) are sequentially arranged in the finder frame. The incident surface and the exit surface of the prisms 46 and 48 are convex lenses.

A distance measuring auxiliary light unit 49 is provided between the finder unit 41 and the flash unit 44 to measure the distance by projecting light of a vertical stripe pattern on a dark object or a flat object. Is interpolated.

On the other hand, the two-arm lever 51 pivotally supported by the support shaft 50 is a break lever having a counterclockwise turning force exerted by a spring 52, and the tip end side of one arm thereof is
A tip 53 having a large friction coefficient, such as rubber, is attached and pressed against the upper surface of the finder cam plate 37, and the other end of the arm has a long hole 51a to provide a zoom button 54.
The shaft portion 54a is fitted.

This blur for the finder cam plate 37
The frictional force of the kill bar 51 is set to be larger than the frictional force of the friction spring 38 provided in the interlocking gear train. Therefore, unless the zoom button 54 is pressed, the friction spring 38 slips and the finder cam plate 37 does not move regardless of the rotation of the first motor 33. That is, the friction spring 38 and the break lever 51 serve as driving force transmission switching means.

The zoom button 54 is axially inserted in the recess of the camera cover 55, and the E-ring 56 is fitted to the shaft portion 54a to prevent the zoom button 54 from coming off. Further, a spring 57 is provided between the button head and the upper cover 55 so that the upward floating force is always applied. The shaft portion 54a of the zoom button 54 is
Although it is fitted in the long hole 51a of the kill bar 51, a zoom switch (not shown) is operated at its lower end.

In the zoom lens camera of this embodiment, when the main switch is turned on and the first motor 33 is rotated,
The zoom lens unit 31 driven by the output gear 32 projects from the retracted position to the shooting position.

In this case, the finder cam plate 37 is not
The killer bar 51 is pressed to prevent its movement. Therefore, the input gear 34 rotates by receiving the driving force from the gear portion 31a, but the interlocking gears 35 and 36 cannot rotate, so that the friction spring 38 slips and idles, and the first motor 33 rotates. The rotational force of the finder cam plate 37
Is not transmitted to.

When the zoom button 54 is depressed to move to zooming, the other arm of the break lever 51 is pushed down by the E-ring 56 fitted to the button 54, so that the lever 51 is small. Turn counterclockwise in the range. As a result, the tip 53 provided on the one arm of the break lever 51 is separated from the finder cam plate 37 to release the break.

Therefore, when the first motor 33 is rotated and the zoom lens unit 31 is zoomed,
The rotation of the input gear 34 is transmitted to the finder cam plate 37 via the friction spring 38, the interlocking gears 35 and 36, and the linear gear 37a, and the finder cam plate 37 moves in the left-right direction according to zooming.

The movement of the finer cam plate 37 is performed by displacing the variable power lenses 42 and 43 so that the image magnification of the finer optical system and the irradiation angle of the flash unit 44 correspond to the focal length of the zoomed photographing lens. Change.

When the depressing operation of the zoom button 54 is released to end the zooming, the break lever 51 returns by the turning force of the spring 52, and the tip 5 of the one arm.
3 is pressed against the finder cam plate 37 to prevent the finder cam plate 37 from moving.

Therefore, if the first motor 33 is subsequently rotated to perform the focusing operation of the zoom lens unit 31, the friction spring 38 slips and the finder cam plate 37 moves as the input gear 34 rotates. do not do.

That is, even if the photographing lens moves during the focusing operation, the image magnification of the finder optical system and the irradiation angle of the flash unit 44 are maintained in a state corresponding to zooming. This zoom lens camera is shutter-released in this state.

FIG. 2 is a perspective view similar to FIG. 1, showing a lens and a driver of the zoom lens camera of the second embodiment. The present embodiment is characterized in that the interlocking gear train for driving the finder optical system is provided with a clutch which is a driving force transmission switching means, and this clutch is connected during zooming. Others are as described above. It is similar to the first embodiment.

In this embodiment, the input gear 34 is connected to the rotary shaft 34.
A clutch gear 58 is slidably supported on the rotary shaft 34a while being fixed to the shaft a. That is, the key groove formed in the shaft hole of the clutch gear 58 fits into the key groove formed in the rotary shaft 34a, and the clutch gear 58 is rotated by the rotary shaft 34.
It is designed to rotate integrally with a.

Further, the clutch gear 58 is constantly pushed toward the input gear 34 side by receiving the expanding force of the spring 59, and in the normal state, the clutch gear 58 is disengaged from the interlocking gear 36 and is not connected.

Further, in this embodiment, a clutch lever 61 pivotally supported by a support shaft portion 60 is provided.
A bifurcated portion 61a is formed on the one arm tip side of the lever 61, and the bifurcated portion 61a is connected to the input gear 34 and the clutch gear 5.
8, and the rotary shaft 34a is slidably held by the forked portion 61a.

A slope portion 61b is provided on the other arm tip side of the lever 61, and the shaft portion 54a of the zoom button 54 is brought into contact with the slope portion 61b. The lower end of the shaft portion 54a of the zoom button 54 is hemispherical, and the slope portion 61b is formed at the initial stage of the depression operation of the zoom button 54.
Is pressed, and the clutch lever 61 turns counterclockwise.

By the counterclockwise turning of the clutch lever 61, the clutch gear 58 is pushed against the expanding force of the spring 59 and moves so as to mesh with the interlocking gear 36 as shown by the dotted line in the figure, and the clutch It becomes a connected state.

The zoom lens camera of the second embodiment is
When the zoom button 54 is pressed, the clutch gear 58
Engages with the interlocking gear 36 and becomes a clutch connection, and the rotational force of the first motor 33 is transmitted to the finder cam plate 37.

As a result, similarly to the first embodiment, the image magnification of the finder optical system and the irradiation angle of the flash unit 44 are determined with respect to the zooming of the zoom lens unit 31.

When the depressing operation of the zoom button 54 is released, the clutch gear 58 is pushed back to the input gear 34 side by the expanding force of the spring 59, the clutch is disengaged, and the clutch lever 61 is also at the position shown in the figure. Return to.

It should be noted that, considering the meshing of the clutch gear 58 with the interlocking gear 36, the clutch gear 58 has a gear on the interlocking gear 36 side.
It is preferable to form the taper into a taper. Also,
In this embodiment, a switch mechanism for zooming can be arranged so as to interlock with the clutch lever 61.

Furthermore, since the clutch gear 58 is not connected to the interlocking gear 36 except during zooming, when the camera receives an impact force, the finder cam plate 37 moves carelessly, and the finder optical system is moved. Image magnification and the irradiation angle of the flash unit 44 do not correspond to the zoom magnification of the taking lens. Therefore, it is preferable to apply an appropriate load to the finder cam plate 37 with a friction spring or the like.

FIG. 3 is a plan view of the finder mechanism of the zoom lens camera of the third embodiment, and FIG. 4 is a bottom view of the finder mechanism. In this embodiment, the lead screw 6 is used.
The finder cam plate 37 is moved by the lead nut 63 which is screw-fed by the rotation of 2.

That is, the lead screw 62 is rotatably supported by the finder frame plate 64, and this lead screw 62 is also rotatably supported.
A lead nut 63 meshing with the screw 62 is fixed to the fin cam plate 37.

A bevel gear 65 provided at one end of the lead screw 62 is rotated by another bevel gear 66 which is rotationally driven by the first motor 33. As a result, the lead screw 62 rotates and the lead nut 63 is screw-fed, so that the finder cam plate 37 moves in the left and right directions, and the image magnification of the finder optical system and the irradiation angle of the flash unit can be zoomed. To determine.

In these drawings, the same reference numerals are assigned to the same members as those in the first and second embodiments described above, but the other reference numerals 67 are eyepieces and 68.
Is the light emitting window (Fresnel lens) of the flash unit, 6
Reference numeral 9 denotes a friction spring that suppresses the careless movement of the finder cam plate 37.

FIG. 5 is a development view of a gear train for transmitting the rotational force of the first motor 33 to the lead screw 62. As shown in the figure, the output of the pinion gear 70 provided on the first motor 33 is transmitted to the interlocking gear 74 via the reduction gears 71 to 73, and the interlocking gear 74 drives the lens drive gear 75 which is long in the axial direction. It is a gear.

An interlocking gear 77 pivotally supported by a lens barrel frame (first moving frame) 76 of the zoom lens unit meshes with the lens driving gear 75. The interlocking gear 77 rotates the same drive ring 78 as that described in the conventional example, and moves the drive ring 78 forward and backward according to the helicoid screw.

The lens barrel 76 is pushed out by the movement of the drive ring 78, and is also pulled back to displace the photographing lenses of the front and rear groups, and then the second group (not shown) is rotated to move the rear group. The fact that the taking lens is displaced to perform zooming is the same as in the conventional example.

On the other hand, a clutch gear 79 is fixed to the rotary shaft 74a of the interlocking gear 74. The rotary shaft 74a is movable in the vertical direction in FIG. 5, but is normally moved downward by the expanding force of the spring 80.

A clutch lever 81 similar to that shown in the second embodiment of FIG. 2 is inserted between the interlocking gear 74 and the clutch gear 79, and when a zoom button (not shown) is depressed. This clutch lever 81 is the clutch gear 79.
Is moved so as to mesh with the finder interlocking gear 82.

In this way, in the clutch connected state in which the clutch gear 79 meshes with the finder interlocking gear 82, the bevel gear 66 described above receives the rotational force of the first motor 33 and rotates,
The lead screw 62 is rotationally driven.

When the pressing operation of the zoom button is released,
The clutch gear 79 is pushed back by the expanding force of the spring 80, and is separated from the finder interlocking gear 82. Therefore, only the lens barrel frame 76 of the zoom lens unit is the first
It is driven by the motor 33.

As described above, also in the zoom lens camera of this embodiment, the clutch gear 79 meshes with the finder interlocking gear 82 only during the zooming operation, and the image magnification of the finder optical system and the irradiation angle of the flash unit 44 are zoomed. Determined according to the magnification.

On the other hand, according to the third embodiment shown in FIGS. 3 to 5, it is possible to adjust the back-out of the zoom lens unit after the completion of the camera, which is extremely convenient in manufacturing.

In a zoom lens camera with a lens shutter, the flange back of the lens optical system is not constant due to accumulated errors of parts. Therefore, an appropriate washer is inserted between the camera body and the flange of the lens barrel and screwed to adjust the flange back.

In the zoom lens camera of the third embodiment, since the clutch gear 79 is not connected to the finder interlocking gear 82 in a normal state, the camera is mounted on the adjusting table using a collimator and the first mode is set. The lens barrel is moved in the direction of the optical axis by a motor different from the motor 33, and shifting is performed by zooming.

After measuring the flange back, the first motor 3 including the amount of deviation from the design value of the best focus is measured.
Rotate 3 to change the entire lens barrel. (The shooting lens is at the WIDE or TELE end)

When the back-out adjustment is performed in this way, there are cases where the clutch gear 79 and the finder interlocking gear 82 cannot engage with each other due to tooth misalignment, but at this time, the finder interlocking gear 82 is rotated to engage.

Clutch gear 79 and finder interlocking gear 8
The meshing error of 2 is caused by the finder interlocking gear 82 and the bevel gear 6
Since the speed is reduced during the transmission of the driving force of 5, 66, the lead screw 62, and the lead nut 63, the positional deviation of the finder cam plate 37 can be ignored.

Therefore, if the deceleration structure is divided into a lens drive system and a finder drive system as in the third embodiment, and a clutch mechanism is provided in the finder drive system, shift and back of the zoom lens camera can be performed. It can be done automatically.

Although the clutch gears 58 and 79 which are engaged only during zooming are provided in the above-mentioned second and third embodiments, the clutch gears 58 and 79 are always connected to the interlocking gears 36 and 82.
It is also possible to adopt a configuration in which the above is engaged. In this case,
The clutch gears 58 and 79 are switched to the disengaged state at the first stage of the shutter release (before the focusing operation).

Although the zoom lens camera provided with the finder and the flash mechanism has been described in each of the embodiments, the flash mechanism is not necessarily provided.

[0072]

As described above, in the zoom lens camera according to the present invention, the finder optical system is interlocked with the driving of the photographing lens only during zooming, and the finder optical system is driven when the photographing lens for focusing is driven. Since the system interlocking is separated, the image magnification of the finder optical system is determined according to the focal length of the zoomed shooting lens, and this image magnification does not change due to fluctuations of the shooting lens due to focusing. Therefore, it becomes an extremely easy-to-see camera finder of the subject image.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a lens barrel and a drive unit of a finder optical system of a zoom lens camera according to a first embodiment.

FIG. 2 is a perspective view similar to FIG. 1 shown as a second embodiment.

FIG. 3 is a partially cutaway plan view showing a finder mechanism portion of a zoom lens camera according to a third embodiment.

FIG. 4 is a bottom view of a finder mechanism portion according to a third embodiment.

FIG. 5 is a simplified view showing a development of a taking gear and a drive gear train of a finder optical system included in the zoom lens camera of the third embodiment.

FIG. 6 shows a zoom lens provided in a conventional camera, and FIGS. 6A, 6B, and 6C are simplified diagrams showing an operation process of moving the zoom lens to a photographing position.

FIG. 7 shows a zooming operation process of the conventional zoom lens, FIG. 7 (A) shows a state in which the front and rear photographing lenses are integrally moved forward, and FIG. FIG. 6 is a simplified diagram showing a state in which a rear lens unit is moved forward.

[Explanation of symbols]

 31 zoom lens unit 31a gear part 32 output gear 33 first motor 34 input gear 35, 36 interlocking gear 37 finder cam plate 38 friction spring 41 finer unit 42, 43 variable magnification lens 44 flash unit 51 break lever 54 Zoom Button 58 Clutch Gear 61 Clutch Lever 62 Lead Screw 63 Lead Nut 79 Clutch Gear 81 Clutch Lever 82 Finder Interlocking Gear

Claims (1)

[Claims] 1. After zooming by moving the first and second photographing lenses by the first motor and the second photographing lens by the second motor, the first and second photographing lenses are moved by the first motor. A lens driving mechanism for moving and focusing the second photographic lens together with a finder optical system composed of a plurality of lenses different from the photographic lens, and the photographic lens zoomed by interlocking with the first motor. In a zoom lens camera provided with a finder drive mechanism that changes the image magnification of the finder optical system according to the focal length of the finder drive mechanism, the finder drive mechanism transmits a driving force in conjunction with zooming operation, or A zoom lens camera, comprising at least a driving force transmission switching means for non-transmitting a driving force in association with a focusing operation.