JP3199784B2 - 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 lens camera with a barrier, and more particularly to a camera having a zoom lens barrel that does not hinder opening and closing of the barrier.

[0002]

2. Description of the Related Art In recent years, tele / wide, zoom, etc.
Various compact cameras with a lens that can change the focal length of a taking lens are provided.

Many of these cameras use a dedicated motor or the like for driving a zoom lens barrel for switching the focal length of the photographing lens, and rotate the motor forward or backward to widen the zoom lens barrel. → Tele, tele → wide is switched.

Further, the finder optical system for confirming the visual field is constituted by an optical system different from the photographic lens optical system, and the finder optical field is changed according to the operation of the photographic lens optical system. There is also a camera provided with a mechanism for interlocking a finder optical system and the above-described photographing lens optical system.

On the other hand, a camera having no zoom mechanism but having a tele / wide switching mechanism, in which the finder optical system is manually switched to the tele or wide state, and then a release operation is performed. Later, there has been disclosed a camera that extends the photographing lens barrel to a position corresponding to the telescopic or wide state of the finder optical system and performs photographing.

Many of these cameras are of a so-called blade type, in which only the opening of the taking lens barrel is covered with a barrier. In addition, a sliding barrier system that covers not only the photographic lens barrel but also the finder is adopted, so that the barrier cannot be closed in the telephoto state where the photographic lens barrel is extended, until the lens barrel is collapsed. There is also a camera provided with a stopper mechanism for stopping the closing operation of the barrier so that the lens barrel is not pinched by the barrier.

FIG. 18 shows an example of a camera using the above-mentioned slide type barrier system having a conventional tele / wide switching mechanism, and is an external plan view seen from above.

[0008] As shown in the figure, the camera is a camera body.
When the zoom switching knob 3 ' for changing the focal length, which is provided on one side of the upper surface of 1' , is set to the telephoto side T, the zoom switching knob 3 ' is accordingly provided at the center of the front of the camera body 1' . The photographing lens barrel 5 ' is in a state of being extended forward.

FIG. 19 is a diagram showing an example of a photographing sequence when normal photographing is performed using the conventional camera shown in FIG.

First, the photographer opens the barrier 2 ' (see FIG. 18) which is freely openable and closable on the front of the camera body 1' and turns on the power of the camera control circuit (step S).
61). Next, a desired visual field range is set by operating the zoom switching knob 3 ' (see FIG. 18). At this time, the camera performs a zoom operation of the photographing optical system in the lens barrel, and
In general, the zoom operation of the finder optical system is generally performed in conjunction with the zoom operation of the photographing optical system (step S62).

Thereafter, the photographer presses the release button 4 ' (FIG. 18).
(See step S63), the camera performs photometry, distance measurement (step S64), and focusing (step S65), and then exposes the film surface by opening and closing the shutter (step S66). Ko
Wind up (step S67). And the photographer
Operate the camera switching knob 3 'to move the photographing lens barrel 5'.
(See FIG. 18) is retracted (step S68), and after confirming that the taking lens barrel 5 ' has collapsed, the barrier 2' is closed and the power of the camera body 1 ' is turned off ( see FIG. 18). Step S69).

[0012]

A camera having such a conventional tele / wide or zoom mechanism can operate in any of the wide-to-tele or tele-to-wide directions in view angle setting operation. In addition, it is necessary to rotate the cam ring or the like forward or backward by rotating the motor forward or backward, and therefore, in many cases, a dedicated motor for driving the zoom lens barrel is provided. A control circuit for controlling the forward / reverse rotation of the camera is required, which causes an increase in the size of the camera body and an increase in cost.

In the camera, as described above, it is necessary to provide a complicated interlocking mechanism for interlocking the finder optical system with the zooming operation of the taking lens barrel (see FIG. 19). However, this is a constraint on the layout in the camera body, which is a hindrance in design.

Further, in the case of a camera in which after the release operation described above, the photographing lens barrel is extended to a position corresponding to the telescopic or wide state of the finder optical system for photographing, the finder optical system and the photographing lens optical system are linked. No mechanism is required, but it does not have a zoom mechanism,
Further, a forward / reverse motor is required, and a control circuit for the motor must be provided similarly to the camera.

On the other hand, in the camera employing the sliding barrier system (see FIG. 18), as described above, the photographing lens barrel projecting in the telephoto state is not damaged by being sandwiched by the closing operation of the barrier. As described above, a barrier mechanism for stopping the barrier is required so that the barrier can be closed only when the lens barrel is retracted. In this case, the camera body increases and the cost increases. Become.

Further, in the case of the camera having the above-mentioned stopper mechanism, when the photographer attempts to close the barrier in the telephoto state, the barrier cannot be closed unintendedly, which causes discomfort.

The present invention has been made in view of the above-mentioned problems, and solves the above-mentioned problems, and a camera having a zoom mechanism, which does not require the finder optical system and the photographing optical system to be linked with each other. The purpose is to provide.

[0018]

The camera according to the present invention in order to achieve the above object In order to achieve the above, the focal length can be changed met
Between the retracted position and the focal length variable position
A photographic lens barrel having a Do photographing optical system, collapsed position near
Closed position covering the taking lens barrel and the taking lens mirror
Move to camera body between open position to expose barrel
Possible barriers and desired viewing range depending on the photographer's operation
A finder optical system capable of setting a field of view detection means for detecting the set field of view of the full <br/> Ainda optical system, it is rotated only in one direction, the photographing optical
The system was moved from the retracted position to the focal length variable position.
After the cam member and the upper for return movement to the collapsed position
With the barrier in the above open position, the photographer
When the shutter start operation is performed, the cam member is
To be detected by the visual field range detecting means.
Focal length corresponding to the view range of the above finder optical system
A focal length setting means for moving and setting the photographing optical system to a position .

[0019]

[Operation] In the above configuration, the state is such that the barrier is in the open position.
Release shooting operation is performed by the photographer
And driving the cam member in one direction to provide a visual field range detecting means.
Compatible with the view range of the viewfinder optical system detected by
Focal length setting means sets the imaging optical system
Move settings. Then, take a picture at the set focal length position.
Immediately after the end of the shadow, the cam member is continuously driven in the one direction.
To return to the retracted position.
You.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 to 4 are external views of a camera showing a first embodiment of the present invention. FIGS. 1 and 2 are an external front view and a plan view of the camera when a barrier is opened. 3 and 4 are an external front view and a plan view, respectively, when the barrier of the camera is closed.

As shown in FIG. 1, the camera of this embodiment is
A photographic lens barrel 5 is provided at the center of the front of the camera body 1, and a finder window 6 is provided above the photographic lens barrel 5. On the left and right sides of the finder window 6, an autofocus light emission window 7 (hereinafter, referred to as an AF light emission window 7) and an autofocus light reception window 8 (hereinafter, referred to as an AF light reception window 8) sandwich the finder window 6. They are arranged as shown.

On one side of the front surface of the camera body 1, the taking lens barrel 5, the finder window 6, the AF light emitting window 7, and the AF light receiving window 8 when the camera of this embodiment is not used. A barrier 2 for covering and protecting is provided. The barrier 2 has convex guides 2b and 2c (see FIG. 2) projecting in the left-right direction of the camera main body 1 on the rear side of the upper and lower surfaces thereof, respectively, and is located at one side from the center of the camera main body 1. It is slidably fitted in guide grooves 1a and 1c respectively provided in the upper and lower portions of the front surface of the front. Then, the user moves the barrier opening / closing handle 2a protruding from the front side of the barrier 2 so that the camera body 1 is moved.
The opening and closing of the photographing lens barrel 5, finder window 6, AF light emitting window 7, and AF light receiving window 8 in the central portion of the lens can be performed.

FIGS. 1 and 2 show a state in which the barrier 2 is slid to one side of the camera body 1 to expose the photographing lens barrel 5, the finder window 6, the AF light emitting window 7, and the AF light receiving window 8. In this state, a power supply in the camera is turned on, and a control circuit for controlling driving of the entire camera in the camera body 1 (see FIG. 14).
Are in an operating state (see FIG. 5). FIGS. 3 and 4 show the case where the barrier 2 is slid to the center of the camera body 1 to cover the photographing lens barrel 5, the finder window 6, the AF light emitting window 7, and the AF light receiving window 8. In this state, the power supply is off, and the control circuit remains off.

Returning to FIGS. 1 and 2, a release button 4 is provided on one side of the upper surface of the camera body 1, and a strobe light emission window 9 is provided on one side of an upper front portion of the camera body 1. Each is arranged. Further, a zoom switching knob 3 for tele / wide switching is provided behind the release button 4 on one side of the upper surface of the camera body 1. The state of the zoom switching knob 3 shown in FIG. 2 indicates that the finder optical system 71 (see FIG. 7) is in the wide state.

Next, a photographing sequence at the time of photographing using the camera of the first embodiment having such a schematic configuration will be described with reference to the sequence diagram of FIG.

First, the photographer opens the barrier 2 of the camera body 1 and turns on the power supply to the camera control circuit (see FIG. 14) (step S1). Next, a desired visual field range is set by operating the zoom switching knob 3 (see FIG. 2). At this time, in a conventional camera, it is common to perform a zoom operation of a photographic optical system in a photographic lens barrel and perform a zoom operation of a finder optical system in conjunction with the zoom operation of the photographic optical system. The operation of the camera of this embodiment is different from that of the conventional camera, and the details will be described later. However, the zoom operation of the finder optical system is performed without performing the zoom operation of the photographing optical system (step S2).

Thereafter, when the photographer operates the release button 4 (see FIG. 1) (Step S3), the camera performs photometry and distance measurement (Step S4), and then, by means described later, the photographing lens barrel. 5 (see FIG. 1), the zoom optical system is moved to a position corresponding to the zoom operation of the finder optical system (step S5). Then, after performing focusing (step S6), the camera exposes the film surface by opening and closing the shutter (step S7). Next, the camera resets the taking lens barrel 5 by means described below, that is, puts the film in a retracted state (step S8), and then winds up the film by one frame (step S9). The photographer closes the barrier 2 and turns off the power of the camera body 1 without confirming that the photographing lens barrel 5 is in the collapsed state (step S10).

FIGS. 6 to 9 are views showing the structure of the finder section 70 in the camera of the first embodiment.
The finder section 70 includes a finder optical system 71.
(See FIGS. 7 and 9) and the finder switching unit 72 (see FIGS.
6 and 7 show a wide state, and FIGS. 8 and 9 show a telephoto state. 6 to 9, the left side is the front side of the camera, and the right side is the rear side of the camera.

The viewfinder 70 has a cylindrical lens support frame at the front of the camera and a prism support at the rear of the camera, and is fixed at a predetermined position in the camera body 1 (see FIG. 1). The finder body frame 10 is provided with cam plate support portions 10b and 10c projecting upward from the upper front part and the upper center rear part of the finder body frame 10, respectively. This support 10
b and 10c have guide grooves 10 so as to face each other.
The cam plate 11 is slidably fitted to the front upper surface of the finder body frame 10 in a direction perpendicular to the finder optical axis so as to be sandwiched between the guide grooves. ing.

The lens holding frames 14 and 16 are inserted into the lens supporting frame in front of the finder frame 10 so as to be movable in the axial direction. Pins 12 and 13 are provided on the outer periphery of the upper portions of the lens holding frames 14 and 16, respectively.
These pins 12 and 13 pass through straight grooves 10 a formed in the optical axis direction on the upper part of the finder body frame 10, and are respectively inserted into cam grooves 11 a and 11 b formed on the cam plate 11. Has been inserted.

The finder optical system 71 includes a lens 1
5, a real image finder optical system including an objective lens group including a lens 17, a Porro prism 18, and an eyepiece 19. The lenses 15 and 17 are fixed in the lens holding frames 14 and 16, respectively, and the Porro prism 18 is mounted on the finder body frame 1.
The eyepiece 19 is disposed in a rear portion of the finder body frame 10 in a prism support portion 10f formed near the center rear of the lens frame 0.

The subject image formed by the objective lens group (lenses 15 and 17) is formed into an erect image by the Porro prism 18, and then observed through the eyepiece 19. In FIG. 7, the Porro prism 18 is not shown in a sectional view but in a side view as viewed from the side.

On the other hand, as shown in FIG. 6, the finder switching section 72 including the cam plate 11 is such that one side of the upper portion of the cam plate 11 in the figure is integrated with the zoom switching knob 3. The zoom switching knob 3
The camera body 1 is moved in the left and right directions so as to move in the direction indicated by the arrow X in FIG. 6 or in a direction opposite to the X direction. Further, since the straight groove 10a extends along the axial direction of the finder body frame 10 and the cam grooves 11a and 11b are formed as left-up grooves as shown in the figure, the zoom switching knob 3 is turned to the arrow X. When the cam plate 11 moves to an arbitrary position in the direction, the cam plate 11 also moves in the arrow X direction. Therefore, the pins 12 and 13 fitted in the cam grooves 11a and 11b respectively move toward the front side of the camera, and thereby the lens holding frame 1 is moved.
The lenses 4 and 16 allow the lenses 15 and 17 to move linearly to an arbitrary position ahead of the finder optical system 71 in the optical axis direction.

FIGS. 6 and 7 show the finder optical system 7.
8 and 9 show the finder section 70 when the camera 1 is in the wide state.
Shows the finder section 70 in the telephoto state.

A contact piece 20 made of an elastic conductor having a bifurcated tip, for example, phosphor bronze is provided at a position of the cam plate 11 facing the zoom switching knob 3 at an upper portion in the figure. Are fixed as shown. Below the contact piece 20, a lower part is fixed at a predetermined position in the camera body 1, and a resistive pattern 2 having an arbitrary resistance value is formed on the upper part.
A resistor substrate 21 is provided in which 2 and conductor patterns 23 having a resistance value of almost 0 are arranged in a row.

The forked ends of the contact piece 20 are respectively
As shown in FIG. 6, which is in sliding contact with the resistance pattern 22 and the conductor pattern 23,
From the position shown in FIG. 8 to the position shown in FIG. Terminals 25 and 26 are connected to both ends of the resistance pattern 22 as shown in FIG.
A terminal 24 is connected to one end on the upper side in FIG.
The resistance value between the terminal 24 and the terminal 25 or the terminal 26 changes according to the position of the contact piece 20, and the resistance value corresponds to the position of the lenses 15 and 17, that is, the view range of the finder. Is shown. In addition, each of the terminals 24 to 26
Is connected to a finder zoom setting position detection circuit 52 (see FIG. 14) in the camera body 1, and the resistance value is determined by the CPU 51 connected through the detection circuit 56.
(See FIG. 14).
The CPU 51 knows the positional relationship of the finder optical system 71 from the read resistance value.

FIGS. 10 to 12 are enlarged cross-sectional views of a main part showing a zooming mechanism of the photographing lens barrel 5 of the camera of the first embodiment.

In FIG. 10, the photographing lens barrel 5
Is the film aperture 1 of the camera body 1 at the rear end.
cylindrical fixed frame 4 having an attachment portion 43b around
A cylindrical cam ring 39 is rotatably fitted on the outer periphery of the fixed frame 43. The cam ring 3
9 is locked by a cam ring pressing plate 41 fitted to the outer peripheral portion of the fixed frame 43 at the distal end thereof.
9 cannot move in the optical axis direction.

In the fixed frame 43, a cylindrical first group lens outer frame 29 and a second group lens frame 35 are movably inserted in the axial direction. The rear portions of the first-group lens outer frame 29 and the second-group lens frame 35 project inward and outward, respectively. Parallel, through hole 2
9a, 35a and guide holes 29b, 35b are formed. Further, a main shaft 44 and a guide shaft 45 whose base ends are fixed to the fixed frame mounting portion 43b and whose ends extend parallel to the optical axis are arranged at vertically symmetric positions in the fixed frame 43, respectively. . The first group lens outer frame 29 and the second group lens frame 35 are slidably fitted to the main shaft 44 through the through holes 29a, 35a, and the guide shafts are inserted into the guide holes 29b, 35b. The insertion of 45 allows movement in the optical axis direction, but does not allow rotation in the rotation direction with the optical axis as the central axis.

A first group pin 36 is attached to the upper rear outer periphery of the first group lens outer frame 29.
Is formed through the straight guide groove 43 a formed in the fixed frame 43 along the axial direction, and is formed in the cam ring 39.
It is inserted into the group cam groove 39a. Similarly to the first group lens outer frame 29, a second group pin 37 is also attached to the upper rear outer periphery of the second group lens frame 35.
The group pin 37 also passes through the guide groove 43a, and the cam ring 39
Is inserted into the second group cam groove 39b formed in the second group.

The guide groove 43a extends in the optical axis direction. The first group cam groove 39a and the second group cam groove 39
b is formed on the outer peripheral surface of the cam ring 39 by a cam groove inclined with respect to the optical axis. By rotating the cam ring 39, the first group lens outer frame 29 and the second group lens frame 35 It moves linearly along the optical axis direction. In order to prevent external light from entering the gap between the fixed frame 43 and the first group lens outer frame 29, a light shielding cloth slidably contacting the outer circumferential surface of the first group lens outer frame 29 is provided on the inner peripheral surface of the front end portion of the fixed frame 43. 46 are attached.

The first group lens outer frame 29 has a connecting wall with its front end facing inward, and the front end of the shutter body frame 32 is fixed inside the front end of this connecting wall. The shutter main body frame 32 has a cylindrical shape, and a fixed helicoid screw 32a, which is a female helicoid screw, is engraved in the center of the inner peripheral surface thereof, and the first group lens 30 is formed on the rear inner periphery. The exposure control sectors 33 and 34, which are shutter blades, are disposed behind the exposure control sectors 33 and 34.
8 (see FIG. 14) to open and close.

The first lens group frame 31 is inserted into the shutter main body frame 32 so as to be movable in the optical axis direction. A helicoid screw 31a composed of a male helicoid screw for moving the lens frame is engraved on the rear outer peripheral surface of the first group lens frame 31, and is arranged so as to screw with the fixed helicoid screw 32a of the shutter body frame 32. Has been established.

On the inner peripheral surfaces of the first lens group frame 31 and the second lens group frame 35, the first lens group 30,
The second group lens 38 is adhesively fixed. The first lens group frame 31 is provided with a focus lens feeding drive mechanism 5.
7 (see FIG. 14) around the optical axis of the first lens group 30.
It becomes to be rotated to, and is capable of adjusting the focal position of the first lens 30 so as to pay out the optical axis direction by the rotational movement.

A drive ring 40 provided with a gear 40a on its peripheral surface is fixed to the outer periphery of the distal end of the cam ring 39, and the gear 40a is connected to a lens barrel zoom drive mechanism 56 (FIG. 1).
4). The cam ring 39 is rotated by the driving force of the lens barrel zoom driving mechanism 56. This cam ring 39
Is the rotational position of the zoom encoder 42 provided on the rear outer peripheral surface of the cam ring 39, for example, formed of a resistance pattern or the like.
Can be known by reading with a zoom position detection mechanism 60 (see FIG. 14) disposed in the vicinity of. The zoom encoder 42 may use a gray code, a magnetic tape, or the like in addition to the resistance pattern.

The first group cam groove 39a and the second group cam groove 39b are both formed by cam grooves engraved on the inner peripheral surface of the cam ring 39, and are formed in a part of the cam grooves 39a, 39b. Is an assembling hole 39c vertically penetrating the cam groove,
39d is drilled. The holes 39c and 39d are through holes for assembling and fixing the first group pin 36 and the second group pin 37 to the first group lens outer frame 29 and the second group lens frame 35, respectively. Is screwed to the lens frames 29 and 35 from outside through the holes.

FIG. 13 is a developed view of the cam ring 39 as viewed from the outer peripheral surface side. Note that, in the drawing, the first group cam groove 39a and the second group cam groove 39b actually correspond to the cam ring 3 as described above.
Although not appearing on the outer peripheral surface of 9, it is shown by a solid line for convenience.

As shown in FIG.
a and 39b depict a mountain-shaped curve having a vertex at a position (an angle of 180 ° in the figure) at which the cam ring 39 is rotated by about half. When rotated in the direction of arrow Y , the guide groove 4
The first group pin 36 and the second group pin 37 guided by 3a are moved along the first and second group cam grooves 39a and 39b, respectively, and move in the optical axis direction indicated by arrow Z in the figure. As a result, the first group lens outer frame 29 and the second group lens frame 35 to which the first group pin 36 and the second group pin 37 are fixed, respectively,
It moves along the main axis 44 and the guide axis 45 in the optical axis direction, and the first group lens 30 and the second group lens 38 move in the optical axis direction.
The focal length as a photographing lens changes according to the change in the position .

When the first group pin 36 and the second group pin 37 are at the position indicated by the symbol A in the drawing (this position is a reference angle of 0 ° in the rotation direction), the first group lens outer frame 29 and the second group lens The frame 35 is in the retracted state located closest to the rear in the optical axis direction, and the state inside the taking lens barrel 5 at this time is shown in FIG. The pins 36 and 37 are the same
When the lens is at a position B which is slightly rotated from the position B, the first lens group outer frame 29 and the second lens group frame 35 are in the wide state, and the state inside the photographing lens barrel 5 at this time is shown. 11 is shown. When the pins 36 and 37 are located at a position indicated by reference numeral C, that is, at a position rotated by about 90 ° with respect to the position indicated by the reference numeral A, the first group lens outer frame 29 and the second group lens frame 3
5 is in the standard state.

When the pins 36 and 37 are located at the position indicated by the reference numeral D, that is, at the position rotated by 180 degrees with respect to the position indicated by the reference numeral A, the first group lens outer frame 29 and the second group lens frame 35 The telephoto state is located closest to the front in the optical axis direction, and the state in the photographing lens barrel 5 at this time is shown in FIG.
Shown in In the first and second group cam grooves 39a and 39b, since the moving directions of the pins 36 and 37 are reversed from the position of the reference symbol D, the cam ring 39 subsequently continues to rotate in the same direction. Then, the first group lens outer frame 29 and the second group lens frame 35 are retracted, and when the cam ring 39 rotates at a rotation angle of 360 °, that is, one rotation, it finally reaches a collapsed state.

FIG. 14 is a block diagram showing an electric circuit of a control circuit in the camera of the first embodiment.

In the figure, a CPU 51 is the core of a control circuit in the camera and controls the following circuits and mechanisms.

The CPU 51 has its input terminals P1, P
2, P3, P6, and P8 each have the release button 4
Are connected to the release switch 50, the output terminal of the finder zoom set position detection circuit 52, the output terminal of the zoom position detection mechanism 60, the output terminal of the photometry circuit 53, and the AF light receiving window 8. The output terminals of the distance measuring circuit 54 are connected, and receive an output signal from these output terminals to control a motor drive circuit 55 and the like described later. In the CPU 51, the output terminals P4, P5, and P7 have the motor drive circuit 55 and the photometry circuit 5, respectively, serving as a drive source of a drive system of the camera.
3. It is connected to the input terminal of the distance measuring circuit 54 and controls these circuits.

The motor drive circuit 55 has output terminals P10, P11, P12, and P13, respectively, for the lens barrel zoom drive mechanism 56 and the lens extension drive mechanism 5.
7, shutter drive mechanism 58, film rewinding mechanism 59
, And controls these mechanisms in accordance with instructions from the CPU 51.

The operation of the above-configured camera of the first embodiment will be described with reference to the flowchart of FIG. 15 showing the operation of the CPU 51.

First, the photographer opens the barrier 2 of the camera body 1, turns on the power supply to the control circuit of the camera (see FIG. 14), and activates the CPU 51 (start of FIG. 15). The CPU 51 that has started operation operates the release button 4
Waits until the release switch 50 linked to is turned on (step S21). When the photographer operates the release button 4 (see FIG. 1) and the release switch 50 is turned on, the CPU 51 instructs the photometric circuit 53 to perform photometry (step S22) and instructs the distance measuring circuit 54. To measure the distance (step S23). Next, the current position of the finder optical system 71 (see FIG. 6), that is, the finder, is obtained from the output signal of the finder zoom setting position detection circuit 52 to which the resistance value of the resistor substrate 21 (see FIG. 6) is input. The focal length is recognized (step S24), and data based on the information of the output signal is stored.

Next, the CPU 51 issues an instruction to the motor drive circuit 55 based on the above data, and drives the lens barrel zoom drive mechanism 56 to zoom the photographic optical system in the photographic lens barrel 5 (step). S25), the zoom encoder 4 fixed to the taking lens barrel 5
2 (see FIG. 10), the current position of the taking lens barrel 5 is detected from the output signal of the zoom position detecting mechanism 60, and the position of the taking lens barrel 5 corresponds to the finder focal length. The lens barrel zoom drive mechanism 56 is driven until the position is reached (step S26). When the zoom encoder 42 reaches a desired position in step S26, the operation of the lens barrel zoom drive mechanism 56 is stopped, and the zoom operation of the photographing lens barrel 5 ends (step S27).

Next, the CPU 51 proceeds to step S23.
In step S28, focusing is performed by driving the lens extension drive mechanism 57 so that the object distance measured in step S3 is in focus. Thereafter, the film surface is exposed by opening and closing the shutter drive mechanism 58 (step S29), and the lens barrel zoom drive mechanism 56 is driven to bring the photographing lens barrel 5 into the retracted state (step S29). S30) The film winding / rewinding mechanism 59 is driven to wind up the film by one frame (step S31). If the main switch of the camera (according to the opening / closing operation of the barrier 2 in the first embodiment) is on, the flow returns to step S21 again to enter the standby state of the release operation. If the switch is off, the operation is started. Is ended (step S32).

The information on the setting position of the finder zoom need not be read after the release operation as described above. For example, the information is always read immediately after the power supply of the control circuit is turned on, and the release switch 50 is turned on. The above-mentioned position information immediately before the above may be stored. Alternatively, the release switch 50 may be constituted by a two-stage switch, and the operations of photometry and distance measurement may be performed by turning on the first stage of the release switch 50. In this case, the position information may be stored when the first stage is turned on.

Next, a camera according to a second embodiment of the present invention will be described with reference to FIGS.

The camera of the second embodiment is obtained by replacing the cam ring 39 of the camera of the first embodiment with a cam ring 39 'having a cam groove having the shape shown in FIG. However, the lens extension drive mechanism 57 in the camera of the first embodiment is not required, and the position of the first lens group frame 31 is fixed with respect to the shutter body frame 32. . Other configurations and operations are the same as those of the camera of the first embodiment.

FIG. 16 is a developed view of the cam ring 39 'as viewed from the outer peripheral surface side. In the drawing, the first and second group cam grooves 3
9a 'and 39b' are actually cam grooves formed in the inner peripheral surface as in the case of the first embodiment.
Although not shown on the outer peripheral surface of 9 ', it is shown by a solid line for convenience.

As shown in the figure, the first group cam groove 39a '
While the cam ring 39 'draws a mountain-shaped curve with the vertex at the position where the cam ring 39' is rotated about halfway (position at an angle slightly larger than 180 ° in the figure), the second group cam groove 39b ' And the cam ring 39 ′ on the left side in the drawing has a rotation angle of 0 °
When it is located at about 180 °, it is formed in a stepped shape rising to the right.
When it is located at 360 °, it is formed as a substantially straight inclined cam groove which is lower rightward. Then, similarly to the camera of the first embodiment, when the cam ring 39 'rotates in the direction of the arrow Y' in the drawing by the driving force of the lens barrel zoom driving mechanism 56, the cam ring 39 'is guided by the guide groove 43a of the fixed frame 43. Group pin 36 '
And the second group pin 37 'are connected to the first group cam grooves 39a', 39
It is pushed along b ′ and moves in the optical axis direction indicated by arrow Z ′ in the figure. Thereby, the first group pin 36 'and the second group pin 3
1 group lens outer frames 29, 2 respectively fixed to 7 '
The group lens frame 35 moves in the optical axis direction along the main axis 44 and the guide axis 45, and changes in the positions of the first group lens 30 and the second group lens 38 in the optical axis direction cause a focal length as a photographing lens. Changes.

The first group pin 36 'and the second group pin 37'
Is the position of the symbol a in the figure (this position is the reference angle 0 in the rotational direction)
°)), the first group lens outer frames 29, 2
The group lens frame 35 is in the retracted state located closest to the rear in the optical axis direction, and when the pins 36 ′ and 37 ′ are located at the position of the symbol “b” slightly rotated from the position of the symbol “a”, the first lens group is The lens outer frame 29 and the second group lens frame 35 are in a wide state. When the pins 36 ′ and 37 ′ reach the position of the symbol k via the positions of the symbols c to j, that is, the position rotated by an angle of about 180 ° with respect to the position of the symbol a, the first lens unit The outer frame 29 and the second group lens frame 35 are in the telephoto state located closest to the front in the optical axis direction. After that, when the cam ring 39 ′ continues to rotate in the same direction, the first group lens outer frame 29. , The second lens frame 35 are retracted, and when the cam ring 39 ′ rotates by 360 °, that is, one rotation, the lens frame 35 is collapsed.

FIG. 17 is a flowchart showing the operation of the camera according to the second embodiment thus configured.
This will be described with reference to FIG.

First, the photographer opens the barrier 2 of the camera body 1, turns on the power supply to the control circuit of the camera (see FIG. 14), and operates the CPU 51 (start of FIG. 17). The CPU 51 that has started operation operates the release button 4
Waits until the release switch 50 linked to is turned on (step S41). When the photographer operates the release button 4 (see FIG. 1) and the release switch 50 is turned on, the CPU 51 instructs the photometric circuit 53 to perform photometry (step S42) and instructs the distance measuring circuit 54. To measure the distance (step S43). Next, the current position of the finder optical system 71 (see FIG. 6), that is, the finder, is obtained from the output signal of the finder zoom setting position detection circuit 52 to which the resistance value of the resistor substrate 21 (see FIG. 6) is input. The focal length is recognized (step S44), and data based on the information of the output signal is stored.

The flow up to this point is the same as that of the camera of the first embodiment. However, in the case of the camera of the second embodiment, the CPU 51 next sets the photographing optical system in the photographing lens barrel 5 to the above data. From the positions b, d, f, h, and j in FIG. 16, the position closest to the focal length corresponding to the finder visual field range immediately before the release operation is calculated (step S45). Based on the information of the distance measurement result in S43, in FIG.
), M2 (between signs d and e), M3 (between signs f and g),
The movement amount of the photographing optical system to the focus position between any of M4 (between symbols h and i) and M5 (between symbols j and k) is calculated (step S46).

Then, in order to move the photographing optical system to the optimum position based on the calculation result, the motor drive circuit 55
Is issued and the lens barrel zoom drive mechanism 56 is driven to zoom the photographing optical system (step S
47) detecting the current position of the photographing lens barrel 5 from the output signal of the zoom position detecting mechanism 60 for detecting the position of the zoom encoder 42 (see FIG. 10) fixed to the photographing lens barrel 5; The lens barrel zoom drive mechanism 5 is moved until the position of the photographing lens barrel 5 reaches the optimum position.
6 is driven (step S48). When the zoom encoder 42 reaches a desired position in step S48, the operation of the lens barrel zoom drive mechanism 56 is stopped, and the zoom operation of the photographing lens barrel 5 is terminated (step S4).
9).

Next, the CPU 51 controls the shutter driving mechanism 5
8 is opened and closed to expose the film surface (step S50), and the lens barrel zoom drive mechanism 56 is driven to bring the photographing lens barrel 5 into the retracted state (step S51). The return mechanism 59 is driven to wind up the film by one frame (step S52). If the main switch of the camera (also in the second embodiment, accompanying the opening / closing operation of the barrier 2 as in the first embodiment) is on, the flow returns to the step S41 again to enter the standby state for the release operation. If the switch is off, the operation ends (step S53).

As described above, in the camera of the second embodiment, the focal length corresponding to the finder visual field range is, for example, 1
When the group pin 36 'and the second group pin 37' are closest to each other when they are at positions near the reference numeral "b" in FIG. 16, the cam ring 39 'first rotates until the pins 36' and 37 'reach the positions shown by the reference numeral "b". Then, the lens is rotated to a position corresponding to the section M1 of the reference numerals b to c so as to be a focus position according to the distance measurement result. During this section M1, the second group cam groove 39b 'is not displaced in the optical axis direction, and the first group cam groove 39a' is displaced linearly. Thereby, the first group lens 30 (see FIG. 10)
Only the movement is performed, and optically, the same result as the focusing by extending the first lens group frame 31 (see FIG. 10) in the first embodiment is obtained. Therefore, in the camera of the second embodiment, the lens extension drive mechanism 56 for extending the first lens group frame 31 in the camera of the first embodiment is unnecessary, and the first lens group frame 31 is also provided with the shutter. The position may be fixed with respect to the main body frame 32 (see FIG. 10).

The extension of the focus lens in the section M1 is similarly performed in the sections M2 to M5, and in the second embodiment, the sections M1 to M
Although the five sections are set to five, the present invention is not limited to this. The zoom area may be further subdivided to provide more focus lens extension sections.

The position information of the zoom and the focus, which can be determined by the zoom encoder 42, may be provided by providing a slit plate which rotates according to the number of rotations of the cam ring 39 ', and reading the amount of rotation with a photo interrupter or the like. Good.

[0074]

As described above, according to the present invention, the following effects can be expected.

1. An interlocking mechanism between the finder optical system and the photographing optical system becomes unnecessary.

2. Since zoom drive of the taking lens barrel can be realized only by rotating the barrel in one direction, control of the drive motor of the taking optical system can be simplified.

3. Above 1.2. As a result, the camera can be made smaller and less expensive.

4. Since the photographic optical system is zoomed after the release operation, the photographic optical system is in a collapsed state in a normal release standby state, and at this time, the barrier can be closed without interference between the barrier and the photographic lens barrel Becomes Further, unlike the conventional camera, a barrier lock mechanism for preventing interference with the lens barrel is not required.

[Brief description of the drawings]

FIG. 1 is an external front view of a camera according to a first embodiment of the present invention when a barrier is opened.

FIG. 2 is an external plan view of the camera of the first embodiment when a barrier is opened.

FIG. 3 is an external front view of the camera of the first embodiment when a barrier is closed.

FIG. 4 is an external plan view of the camera of the first embodiment when a barrier is closed.

FIG. 5 is a sequence diagram for explaining a photographing operation of the camera of the first embodiment.

FIG. 6 is a plan view of a finder section of the camera of the first embodiment in a wide state.

FIG. 7 is a longitudinal sectional view of a finder optical system in a wide state of the camera of the first embodiment.

FIG. 8 is a plan view of a finder section of the camera of the first embodiment in a telephoto state.

FIG. 9 is a longitudinal sectional view of a finder optical system in a telephoto state of the camera of the first embodiment.

FIG. 10 is an enlarged sectional view of the camera lens barrel of the first embodiment when the taking lens barrel is in a retracted position.

FIG. 11 is an enlarged sectional view of the lens barrel of the camera of the first embodiment when the lens barrel is in a wide state.

FIG. 12 is an enlarged cross-sectional view of the camera lens barrel of the first embodiment when the taking lens barrel is in a telephoto state.

FIG. 13 is a development view of a cam ring portion of the camera according to the first embodiment.

FIG. 14 is an electric circuit block diagram of a control circuit of the camera of the first embodiment.

FIG. 15 is a flowchart showing the operation of the camera of the first embodiment.

FIG. 16 is a development view of a cam ring portion in the camera according to the second embodiment of the present invention.

FIG. 17 is a flowchart showing the operation of the camera of the second embodiment.

FIG. 18 is an external plan view showing an example of a conventional camera.

FIG. 19 is a sequence diagram for explaining a photographing operation of the conventional camera.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Camera body 2 ... Barrier 3 ... Zoom switching knob 4 ... Release button 5 ... Shooting lens barrel 6 ... Finder window 7 ... AF projection window 8 ... AF receiving window 9 ... Flash emission window 10 ... Finder frame 11 ... Cam Plate 30 ... 1st lens 38 ... 2nd lens 39 ... Cam ring 43 ... Fixed frame 51 ... CPU 52 ... Finder / zoom setting position detecting circuit 60 ... Zoom position detecting mechanism 70 ... Finder section 71 ... Finder optical system

Continuation of front page (56) References JP-A-2-63032 (JP, A) JP-A-61-259237 (JP, A) JP-A-2-125217 (JP, A) JP-A-4-277732 (JP) JP-A-61-259210 (JP, A) JP-A-61-259237 (JP, A) JP-A-64-40823 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB G03B 17/04 G02B 7/04-7/10 G03B 11/04 G03B 13/12

Claims (1)

(57) [Claims] The focal length is changeable and retractable.
Imaging optical system that can move between the focal length and focal length zoom position
A photographing lens barrel having a closed position covering the photographing lens barrel in the retracted position;
Camera body between the open position to expose the taking lens barrel
A barrier movable with respect to the desired finder optical system capable of setting a field of view in accordance with the photographer's operation, the field of view detection means for detecting the field of view of the finder optical system set in one direction The above-mentioned photographic optical system is
Moved from the retracted position to the focal length variable position
Thereafter, the photographer returns to the retracted position with the cam member and the barrier in the open position.
When the shutter release start operation is performed, the cam member is
Direction, and is detected by the visual field range detecting means.
Focal length corresponding to the view range of the above finder optical system
The focal length setting means for moving set the photographing optical system in the release position, the provided, which is set by the focal length setting means focus
Immediately after shooting at the distance position, continue the cam member
Drive in the one direction and move the photographing optical system to the retracted position.
The camera is characterized by being moved back to the position .