JPS61219917A - Automatic focusing device - Google Patents

Abstract

PURPOSE:To shorten the time required for automatic focusing, to decrease the power consumption quantity, and also to improve the interlocking accuracy of a photographing optical system and an interlocking mechanism, by providing a gear transmission mechanism and an energizing member. CONSTITUTION:A device is constituted of an electric driving source, a gear transmission mechanism for transmitting a driving force of the electric driving source to an interlocking mechanism, and an energizing member 50c, etc. Also, a gear 50b for suppressing a backlash is engaged to a reduction gear 53a, and the gear 50b is energized in the right turn direction by the energizing member 50c, therefore, the reduction gear 53a is also energized, and a backlash between the gear 53a and 52b, and between a gear 52a and a rack 51b is suppressed. Also, an energizing force of the spring 50c is stored by a driving force of a motor, when a photographing optical system moves forward, and when a main optical system and a sub-optical system move forward at the time of AF, a load of the motor is reduced. In this way, a speed of automatic focusing is increased, also a backlash generated in the gear transmission mechanism is eliminated, and the interlocking accuracy of the photographing optical system and the interlocking mechanism can be improved.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to an electric drive source, a photographing optical system that is reciprocated in an optical axis direction by the drive source, and a photographing optical system that is driven by the drive source. and an interlocking mechanism that moves the photographing optical system forward from its original position to perform automatic focus adjustment in response to generation of a signal to start automatic focus adjustment, and in response to generation of a signal to end automatic focus adjustment. The present invention relates to an automatic focusing device that moves a photographing optical system back to its original position.

BACKGROUND OF THE INVENTION Conventionally, in this type of automatic focusing device, the interlocking mechanism includes, for example, a mechanism for detecting the position and displacement of a photographing optical system, and a movable triangular distance measuring mechanism. All of these mechanisms put a load on the electric drive source during automatic focus adjustment, causing a lengthening of the time required for automatic focus adjustment and an increase in power consumption during automatic focus adjustment.

``Object of the Invention'' The present invention has an extremely simple structure, shortens the time required for automatic focus adjustment, reduces power consumption during automatic focus adjustment, and improves the accuracy of the interlocking mechanism between the photographing optical system and the interlocking mechanism. Another object of the present invention is to provide an automatic focusing device with improved performance.

"Summary of the Invention" In order to achieve the above object, the automatic focus adjustment device of the present invention includes a gear transmission mechanism that transmits the driving force of the electric drive source to the interlocking mechanism, and a biasing member, The biasing member is energized by the electric drive source when the photographic optical system moves backward, and biases the photographic optical system in the forward movement direction, and also suppresses backlash generated in the gear transmission mechanism. It is characterized by removing.

The biasing member functions to improve the speed of automatic focus adjustment by assisting the driving force that moves the photographic optical system forward, and to eliminate backlash generated in the gear transmission mechanism to increase the interlocking mechanism with the photographic optical system. This function also has the effect of improving the accuracy of interlocking with.

r Example” Hereinafter, one embodiment of the present invention will be described based on the drawings.

As shown in FIGS. 3 to 7, a dustproof cover 2 is placed on the front side of the camera body 1 in the left-right direction in FIGS. It is provided so that it can be displaced in the direction (vertical direction in FIGS. 3 to 5), that is, it can be extended and retracted. Inside the camera body 1, there is a sub optical system 4 which together with the main optical system 3 constitutes a photographing optical system.
It can be displaced in the direction across the optical axis of the main optical system 3 (in the left-right direction in Figures 3 to 5) between the position where it is inserted into the light beam of the main optical system 3, that is, the photographing light beam, and the position where it is withdrawn from the light beam. It is provided.

A focal length selection member 5 for switching the focal length of the photographing optical system is provided on the top surface of the camera body 1 so as to be operable at all times.

In FIG. 3, the dust cover 2 is in the open position.

The focal length selection member 5 is located at a telephoto position where the focal length of the main optical system 3 is in a telephoto range, and is opposed to the letter "T" attached to the top surface of the camera body 1. The main optical system 3 is located at an extended position protruding from the front surface of the dustproof cover 2, and constitutes a composite optical system with the sub optical system 4 located at the inserted position to have a focal length in the telephoto range.

In FIG. 4, the dust cover 2 is in the open position.

The focal length selection member 5 is located at a wide-angle position that sets the focal length of the main optical system 3 to a wide-angle range, and is opposed to the letter "W" attached to the top surface of the camera body l. At this time, the main optical system 3 is
It is in a retracted position where it is retracted into the camera body l from the extended position, and the sub optical system 4 is in a retracted position. The main optical system 3 has a focal length in a wide-angle range.

In FIG. 5, the dust cover 2 is in the closed position and covers the main optical system 3. In FIG. At this time, the main optical system 3 is in the retracted position even though the focal length selection member 5 is in the telephoto position, and the sub optical system 4 is in the retracted position. When the dustproof cover 2 is in this closed position, the indicator 2a attached to the top surface of the dustproof cover 2 is attached to the top surface of the camera body l in order to make it visible from the top of the camera that photography is not possible. It is opposite to the letters roFFJ.

As can be seen in FIG. 3, a switch SWI interlocked with the dustproof cover 2 and a switch SW2 interlocked with the focal length selection member 5 are provided within the camera body 1.

The switch SWI consists of a sliding piece 2b fixed to the dustproof cover 2 and a conductive land 2c fixed to the camera body 1, and is turned ON when the dustproof cover 2 is in the open position, and is turned on from the open position to the closed position. When it is displaced, it turns OFF. This switch S%11 controls the rotational direction of a motor 12, which will be described later, for displacing the main optical system 3, and also controls the power supply to a shutter control circuit 31, which will be described later.

The switch SW2 includes a sliding piece 5a fixed to the focal length selection member 5 and a conductor land 5b fixed to the camera body l.
It switches according to the position of the focal length selection member 5, and controls the rotational direction of a motor 12, which will be described later, which displaces the main optical system 3. The switch SW2 is a focal length selection member 5
ON when the camera is in the telephoto position, and O when the camera is in the wide-angle position.
Becomes FF.

In the upper part of the camera body l, a reverse Galilean type finder optical system including a first finder optical system 6 having a positive refractive power and a second finder optical system 7 having a negative refractive power is housed in a finder housing 1a. It is provided.

The finder optical system as a whole is wide at the front and narrow at the rear, and a substantially trapezoidal space is formed in the finder storage portion 1a adjacent to the narrowed portion of the finder optical system.

Further, on both sides of the finder optical system are AF (automatic focusing) optical systems 8a and 8b, a light emitting element 8C is provided after the AF optical system 8a, and a light receiving element is provided after the AF optical system 8b. 8d is provided.

FIG. 2 is a perspective view showing the main optical system displacement mechanism, finder switching mechanism, and other internal mechanisms of this embodiment.

An aperture 10a through which a photographing light beam passes is provided in the center of the plywood 10, and a main optical system 3 is attached to the front part of the aperture 10a.
After that, an aperture/shutter device 11 shown in phantom lines is attached. From the aperture/shutter device 11 is an FPC (flexible printed circuit board) FP for control signal transmission.
Clla is extended.

A motor 12 is fixedly installed as an electric drive source on the upper back surface of the plywood lO, and a bevel gear 12 is attached to one end of the rotating shaft.
a is fixedly installed. This bevel gear 12a has a base plate 1.
A gear 13 pivotally supported by the gear 13 is engaged with the gear 13, and a gear 14 is engaged with a spur gear integral with the gear 13. gear 14
is held rotatably but immovably in the axial direction by a holding arm erected on the plywood 10.

A through hole is made in the center of the gear 14, and the gear! A female thread is cut with the rotation center of No. 4 as the axis. A male thread cut on the guide shaft 15 is screwed into this female thread.

The guide shaft 15 extends in the optical axis direction, and as can be seen in FIG. 10, its end is fitted into the substrate 1c of the camera body 1 and fixed unrotatably with a set screw 15a, and its end is made of plywood. It is inserted into the through hole xob (shown in FIG. 10) of lO so as to be able to slide in the axial direction, and the leading end is fitted into the camera body l.

A guide shaft 18 extending in the optical axis direction is also provided on the substrate 1c. The guide shaft 1B is fitted into a notch IQc in the plate 1O so as to be slidable in the axial direction.

Further, a base of a linear motion cam plate 17 is fixed to the base plate 10 so as to be along the moving direction of the base plate 1O (optical axis direction of the main optical system 3), and the linear motion cam plate 17 has a spring property. A sliding contact portion 17a is formed at the tip.

Sliding part 1? a is slidably pressed against a fixed wall surface (not shown) extending from the substrate IC along the moving direction of the base plate 10.

With this configuration, when the motor 12 rotates, the plywood 10 moves in parallel in the optical axis direction due to the screw engagement between the gear 14 and the guide shaft 15, and the main optical system 3 and diaphragm/shutter device 11 fixed thereto move in parallel. , is displaced in the optical axis direction between the extended position and the retracted position. At this time, the fitting between the guide shaft 1B and the notch 10c prevents the base plate 10 from rotating in a plane perpendicular to the optical axis. Further, the sliding contact portion t7a of the cam plate F comes into elastic contact with the fixed wall surface, so that the guide shaft 18 and the notch 10c come into contact without play. Therefore, the base plate 10 moves in parallel in the optical axis direction without decentering the optical axis of the main optical system 3 while remaining perpendicular to the optical axis.

A reduction gear train 25, a cam gear 2B, and a drive member 27 are pivotally supported on the back surface of the plywood 10, and the sub optical system 4 is screwed and held on the drive member 27 via a support tube 4e.

The input gear 25a of the reduction gear train 25 meshes with a spur gear integral with the gear 13, and the final gear 25b of the reduction gear train 25 meshes with the cam gear 2e.

The cam gear 2B and the drive member 27 are coaxial, and are connected to each other via a front cam 28a provided on the end surface of the cam gear 26.

The reduction ratio of the reduction gear train 25 is set as follows. That is, when the main optical system 3 is in the extended position, the sub optical system 4 is placed in the insertion position (illustrated by imaginary lines in FIG. 2) into the photographing light beam, and when the main optical system 3 is in the retracted position, The sub-optical system 4 is placed at a retracted position M (shown by a solid line in FIG. 2) in which the sub-optical system 4 is retracted from the photographing light beam.

8 and 9 show detailed sectional views of the sub-optical system insertion/removal mechanism.

In the figure, a main optical system 3 and an aperture/shutter device 11 are fixedly installed on a base plate 10 in front of an aperture 10a.
A positioning means 28 for the sub-optical system 4 is formed at the rear of a. The contact surface 28c is perpendicular to the optical axis of the optical system 3.

This positioning means 28 can hold a holding cylinder 4a that integrally holds the sub optical system 4, and when engaged, the optical axis of the sub optical system 4 is aligned with the optical axis of the main optical system 3 in the extended position. The sub optical system 4 is aligned with the optical axis, and the sub optical system 4 is positioned at a predetermined position in the direction of the optical axis.

This optical axis alignment is performed by inserting a small cylinder 4c protruding from the front end surface 4b of the holding cylinder 4a into the inner cylinder surface 28a of the positioning means 28, and the positioning of the holding cylinder 4 in the optical axis direction is
This is done by the end surface 4b of the positioning means 28 coming into contact with the contact surface 28c of the positioning means 28.

The drive member 27 is slidably supported in the axial direction by a fixed shaft 10g implanted in the plywood lO via a bearing portion 27a. The driving member 27 has a circumferential groove 2 that accommodates the sub optical system 4 in a loosely fitted state. b is formed.

A flange 4 is provided on the outer periphery of the holding cylinder 4a of the sub-optical system 4 over the entire circumference.
d, and a coil spring 29 is inserted between the inner circumferential groove 27b and the collar 4d. This spring 29 is
Positioning means 28 for sub-optical system 4 brought to the insertion position
The function is to bias it in the direction of contact.

A cam gear 26 is also pivotally supported on the shaft 10g, and a sliding contact portion 27c provided at one end of the drive member 27 can slide into front cam 2Ela formed on this end surface.

The shaft 10g is provided with collars 10b and 1 so as to sandwich the bearing portion 27a.
A spring 30 is inserted between the collar tob and the drive member 27. The spring 30 is connected to the driving member 2
The sliding contact portion 27c of No. 7 is pressed against the cam 26a, or the front end surface of the bearing portion 27a is pressed against the collar 10i.

Locking members 10j and 10k for locking the free end 27d of the drive member 27 are planted on the base plate 10, and the locking members 10
j locks the swinging of the drive member 27 when the sub optical system 4 is brought to the insertion position, and the locking member 10 holds the swing of the drive member 27 when the sub optical system 4 is brought to the retracted position. Lock the movement.

Further, near the end of the locking member 10, a circular hole 101 is provided into which the small cylinder 4c of the sub-optical system 4 brought to the retracted position is loosely fitted.

FIG. 8 shows the state when the sub-optical system 4 is in the insertion position and in the fully inserted position in which it is engaged with the positioning means 28. The sub optical system 4 also takes the following positions.

That is, there is an incompletely inserted position where the small cylinder 4c is pushed up by the front cam 28a and does not engage the positioning means 28, although it is in the insertion position, and the small cylinder 4c is pushed up by the front cam 28a, although it is above the circular hole 10IL. This is the incompletely retracted position in which the small cylinder 4C has not fallen into the circular hole 10, and the completely retracted position (shown in FIG. 9) in which the small cylinder 4C has fallen into the circular hole tofL.

FIG. 11 and FIG. 12 show front views of the sub-optical system retrograde prevention mechanism that interlocks with the sub-optical system insertion/removal mechanism.

A blocking plate 30a fixed to a blocking gear 30f meshing with the cam gear 2B has a first small diameter portion 30b and a first small diameter portion connected in sequence.
The engaging surface 30c, the second small diameter portion 30d, and the second engaging surface 3
0e. The first engaging surface 30c and the second engaging surface 30e can each engage with an engaging portion 27e provided near the bearing portion 27a of the drive member 27.

FIG. 11 shows a state in which the sub-optical system 4 is locked in a fully retracted position or an incompletely retracted position, and FIG. 12 shows a state in which it is locked in a fully inserted position or an incompletely inserted position. .

FIG. 21 shows a cam diagram of the cam 28a.

The cam 28a has a lifting height of 0 as the rotation angle θ ranges from 0 to 01.
A first flat section A that does not change at , a first slope section B where the head increases linearly from 0 to hl from 81 to e2, and a second flat section C where the head does not change at hl from 82 to θ3. , a second slope section in which the lift linearly decreases from hl to 0 from e3 to 380°.

The cam 28a has three effects on the sub-optical system 4.

The first effect is to displace the sub optical system 4 in the optical axis direction of the main optical system 3 between the complete insertion position and the incomplete insertion position.

The second effect is to displace the sub optical system 4 between the incomplete insertion position and the incomplete retraction position in a direction transverse to the optical axis of the main optical system 3. The third effect is to displace the sub optical system 4 in the optical axis direction of the main optical system 3 between the incompletely retracted position and the completely retracted position. The details will be described later.

As shown in FIG. 2, a rack 51 is erected on the back surface of the plywood lO. The rack 51 is guided by a guide shaft 51a whose base end is implanted in the substrate IC and whose front end is loosely fitted into the plywood 10.

The transmission shaft 5 is attached to the rack teeth 51b carved on the rack 51.
Binion 52a fixed to the lower end of 2 is engaged,
A gear transmission mechanism is constructed in the subsequent system. Transmission shaft 5
2 is the photographing optical system and the finder optical system.

A partition plate (not shown) that blocks light and separates the AF optical system, etc.
penetrates through.

A spur gear 52b fixed to the upper end of the transmission shaft 52 is meshed with a reduction gear 53a, and a cam that is a control member and is part of an interlocking mechanism interlocked with the photographing optical system is attached to the upper end of the shaft 50 of the gear 53a. A member 53 is pivotally supported.

A cam plate 71 is fixed to the cam member 53 (13th
14), this cam plate 71 works in conjunction with an active triangulation automatic focusing (hereinafter referred to as AF) device after a cam lever 73, which will be described later, and the photographing optical systems 3 and 4. Further, a detection brush plate 81 is planted on the upper surface of the cam plate 71 and is in sliding contact with a printed circuit board 62, which will be described later.

The detection brush plate 61 and the printed circuit board θ2 also form part of the interlocking mechanism. The brush plate 61 has four brushes 81a and 61b formed of the same conductor and electrically connected to each other.
, 81c, and 81d.

A fixing column 50a is erected on the reduction gear 53a.

A screw 71b inserted into an alWi long hole 71a drilled in the cam plate 71 is screwed into the upper end of the fixing column 50a, so that the cam plate 71 and the cam member 53 are connected to the reduction gear 53a.
are integrally combined with.

As can be seen in FIG. 1, the reduction gear 53a is meshed with a gear 50b for suppressing backlash.
0b is biased in the clockwise direction (in the direction of the arrow) by the spring 50c, which is a biasing member, so that the reduction gear 53a
is also energized, and between gears 53a and 52b and gear 52
Backlash between a and the rack 51b is suppressed. The biasing force of the spring 50c is stored by the driving force of the motor 12 when the photographing optical system returns, and is
When it moves forward during AF (when it is extended in this embodiment),
The load on the motor 12 is reduced.

Cam board 7! An encoder printed circuit board 62 is disposed above the encoder. The printed circuit board 62 is locked at its center by the pivot shaft 50 of the cam member 53, and has an adjustment slot 82a at its periphery.
is provided, and the position is adjusted and fixed by a set screw 82b that is screwed into a threaded emboss formed on the camera body l.

A plurality of sliding contact patterns (not shown) arranged concentrically around the pivot shaft 50 are provided on the lower surface of the printed circuit board 82, and each pattern includes brushes 81a, θlb, and 81c of the detection brush plate 81. , 81d (1) The tips are in contact with each other. As the photographing optical system 3.4 moves the entire distance from the infinity position in the wide-angle area to the close position in the telephoto area, each brush moves 360 degrees around the pivot axis 50.
Rotate at an angle of less than 1 degree. Each brush 81a, Blb,
Each electric signal output from each of the sliding contact patterns changes digitally depending on the position where 81c and 131d contact, that is, the position of the photographing optical system.

By decoding each of these electrical signals, the photographing optical system 3
．． A photographing optical system position signal indicating the position No. 4 is obtained. Also, based on this photographic optical system position signal, the rear '1kf)
ychi SW3. SW4. SW5 ON/OFF is controlled.

The switch SW3 is turned off when the main optical system 3 is in the retracted position, the switch Sw4 is turned off when it is in the extended position, and the switch Sw5 is turned off when it is located between the retracted position and the extended position. Switches S%13 and SW4 function as limit switches, and when the main optical system 3 is displaced to the retracting position or the retracting position, the motor! Cut off the power supply of 2.

The switch SW5 is a switch that prevents the shutter release from being performed when the main optical system 3 is at the intermediate position between the front position and the object image cannot be formed on the film surface, and is a switch that prevents the shutter release from being performed. This is a switch for cutting off power supply to the circuit 31 (shown in FIG. 9).

In FIGS. 15 and 16, the cam member 53 serves as a control member of the finder switching mechanism.

A cam groove 54 is carved in the lower part, a starting tooth 53b is formed on one periphery, and a driving tooth 53c is continuous with one tooth missing from the starting tooth 53b.
, a sliding contact edge 53d is formed.

The switching drive member 55 is located close to the cam member 53 and the swing shaft 55
It is pivotally supported to the finder storage section 1a via a. The switching drive member 55 is connected to the activation tooth 5 of the cam member 53.
3b, an activation tooth 55b corresponding to the drive tooth 53c, a fan-shaped portion 55d having a drive tooth 55c, a first cam surface 55e in a substantially radial direction formed around the swing shaft 55a, and a second cam surface that is a circumferential surface. A cam portion 55g consisting of a cam surface 55f,
A swinging arm 55h extends radially from the swinging shaft 55a.
It consists of

A first objective lens 5B having a positive refractive power is fixed to the tip of a support arm 554 extending upward from the tip of the swing arm 55h, and this first objective lens 58 forms a first finder optical system. There is.

The switching drive member 55 is biased clockwise in FIG. 15 by a spring 55j stretched between it and a bottle protruding from the finder housing 1a.

A second objective lens 57 with negative refractive power constituting the second finder optical system is swingably supported on a linear holder 58 via a swing shaft 57a, and the linear holder 58 is connected to the finder storage section I.
It is supported to be movable in a straight line in the direction of the optical axis of the finder optical path within a.

An engagement rod 57c that extends downward is protruded from the lower end surface of the second objective lens 57, and its tip engages with the cam portion 55g of the switching drive member 55. Said rack 51° transmission shaft 52
．． Cam member 53. Switching drive member 55. Engagement rod 57c
etc. constitute the second finder optical system driving means.

On the other hand, rack 51. Transmission shaft 52. Cam member 53. The switching drive member 55 and the like constitute a first finder optical system drive means.

The cam groove 54 of the cam member 53 is engaged with a driven pin 59 a that projects from the variable power swing lever 53 . The magnification swinging lever 58 has a base end pivoted to the main body 1 via a pivot shaft 59b, and a bottle 5Il protruding from the end extending from the pivot shaft 59b.
A toggle spring 59d is stretched between the lc and the bin 1b fixed to the main body 1 to hold the variable power swing lever 58 at the telephoto position and the wide-angle position.

The cam groove 54 of the cam member 53 includes a first circumferential groove 54a that does not operate the driven bin 59a, and a drive groove 54b that moves the driven bin 513a and swings the variable power swing lever 59.
and a second circumferential groove 54c that does not operate the driven pin 59a.

A substantially U-shaped groove 59 is provided at the tip of the variable power swing lever 59.
e is formed, and the distal end of a vertically moving rod 58e extending downward from a linearly moving connecting arm 58d projecting rearward from the linearly moving holder 58 is engaged with the split groove 59e.

The AF switching device is shown in FIGS. 2, 13, 14, 17, and 18.

That is, a cam surface is formed on the outer periphery of the cam plate 71 by integral molding of synthetic resin, and this cam surface extends from the wide-angle infinity point a to the wide-angle closest point as shown in FIGS. 17 and 18. A wide-angle area C, a transition area d, a standby area e, and a telephoto area from the telephoto infinity point f to the telephoto point g are continuously formed. The direction of the light projecting element 8C is set to be the same as the wide-angle infinity point a, which is the starting point of the focusing operation in the wide-angle area C, and the telephoto infinity point f, which is the starting point of the focusing operation in the telephoto area. On the other hand, the wide-angle closest point and the telephoto closest point g are not the same due to the difference in shooting limit distance.In addition, in this embodiment, the sub optical system 4 is integrated with the main optical system 3 when inserted. Since it moves in the axial direction, the cam shapes in the wide-angle area C and the telephoto area are not the same, but the sub optical system 4 is only inserted and removed and is not displaced in the optical axis direction, and only the main optical system 3 In the photographing optical system that is displaced in the axial direction, the cam shape is the same except for the vicinity of the closest point.

As shown in FIGS. 2 and 13, the driven end 73a of the cam lever 73, which is pivotally supported on the camera body l via the pivot shaft 72, is in sliding contact with this cam surface. 3a is cam lever 7
3 is constantly pressed against the cam surface by a spring 73b that urges the cam surface.

An engagement pin 73c is fixed to the other end of the cam lever 73,
The engagement pin 73c is engaged with an engagement arm 75a of an interlocking lever 75 that is pivotally supported on the camera body 1 via a pivot shaft 74. A light emitter holding lever 76 is installed concentrically with the interlocking lever 75.
is pivotally supported via a pivot 74. Cam lever 73~
The light emitting element holding lever 76 system forms an interlocking mechanism that interlocks with the photographing optical system.

The interlocking lever 75 is biased counterclockwise when viewed from above by a spring 75b wound around the pivot shaft 74, so that the engagement arm 75a is brought into contact with the engagement pin 73c of the cam lever 73. Since the biasing force of the spring 75b is considerably smaller than the biasing force of the spring 73b, the driven end 73a does not separate from the cam surface of the cam plate 71.

An adjustment eccentric pin 75c is erected at the end of the interlocking lever 75, and the top 75d of the adjustment eccentric pin 75c is inserted into a long hole 78a at the end of the light emitting element holding lever 7G. Engagement arm 75a of interlocking lever 75 and light emitting element holding lever 7
A tension spring 7Elb is stretched between the ends of the springs 6 and 6.

The interlocking lever 75 and the light emitting element holding lever 7B operate almost integrally, and the light emitting element 8C is held by the light emitting element holding lever 78, and the camera body is held together by the spring 78c as a whole, as shown in FIG. It is urged downward in the figure so as to come into contact with the end face of the bearing portion of 1, and is pivotally supported by the bearing portion.

FIG. 2 further shows a finder distance display switching mechanism.

That is, a driven lever 82 is pivotally supported on the camera body 1 via a pivot shaft 81, and a driven pin 82a fixed to one end of the driven lever 82 is connected to a cam groove 1 formed in a direct-acting cam plate 17.
7b.

A slide lever 83 is connected to the driven lever 82.
The camera body 1 is supported so as to be slidable in the lateral direction via bins 84a and 84b erected in the camera body 1 and guide holes 83a and 83b formed in the slide lever 83.

An engagement pin 83c is fixed to one end of the slide lever 83, and the engagement pin 83c engages with a fork portion 82b formed at the other end of the driven lever 82.

The slide lever 83 is provided with pointers 83d and 83e that are located in front of the fixed lens 7a of the finder optical system and can be selectively placed within the field of view of the finder.

FIG. 19 shows a monitor control circuit for driving the optical system 3.4 of this embodiment.

In the figure, the motor 12 is driven by three power supply circuits.

The first path is a path from the positive electrode of the power source E to the switch 5Il13 to the switch 7a to the motor 12 to the switch 5W7b to the negative electrode of the power source E. By supplying power through this path, the motor 12 rotates, displacing the main optical system 3 to the retracted position and displacing the sub optical system 4 to the retracted position.

The second path is a path from the positive electrode of the power source E to the switch 5t114 to the switch 5W8a to the motor 12 to the switch 5Web to the negative electrode of the power source E. By supplying power through this route, the motor 12 rotates in the opposite direction to that during the first route, displacing the main optical system 3 to the feeding position and displacing the sub optical system 4 to the insertion position.

Here switches 5W7a, 5W7b, 5W8a, 5W8
b is a semiconductor switch whose opening/closing is controlled by a logic circuit 40 (shown in FIG. 20), which will be described later.

The third path is the autofocus T19 shutter control circuit 3
1 and the motor 12, and the motor 12 is rotated in forward and reverse directions by the output of this control V4 circuit 31, causing the optical system to move back and forth in the optical axis direction to bring the focus into alignment.

In the power supply path of this control circuit 31, switches 5W1a and SW5 connected in series are inserted. switch 51
1a is a semiconductor switch that is controlled by the switch 5llll and opened and closed in the same phase as this, and is turned ON only when the dustproof cover 2 is in the open position. switch 51
15 is turned on only when the main optical system 3 is at the extended position and the retracted position (when the sub optical system 4 is at the fully inserted position and completely retracted position). With these, the dustproof cover 2, optical system 3,
4 is in an inappropriate position for photographing, automatic focus adjustment and shutter operation are prevented.

FIG. 20 shows a logic circuit 40 that controls the operation of the motor control circuit of FIG. 19. This logic circuit 40 includes a pair of input terminals 40a, 40b, a pair of output terminals 40c,
40d. The input terminal 40a is connected between the switch 5Ill and the grounding resistor, the input terminal 40b is connected between the switch SW2 and the grounding resistor, the output terminal 40c is the control terminal of the switches 5W7a and 5W7b, and the output terminal 40d is connected to the switch 5W8a, 8b, respectively.

The input terminal 40a is at the old GH level when the switch 5idl is ON, that is, when the dustproof cover 2 is in the open position, and is at the Low level when the switch 5tllll is OFF, that is, when the dustproof cover 2 is in the closed position.

The input terminal 40b is connected to the old GH when the switch 5Ii12 is ON, that is, when the focal length selection member 5 is at the telephoto position.
When the switch SW2 is OFF, that is, when the focal length selection member 5 is at the wide-angle position, it becomes the Low level.

When the output terminal 40c is at High level, the above switch 5
Turn on both 117a and 5W7b, and turn them off at Low L/Bevel. The output terminal 40d turns on both the switches 5W8a and S8b when the output terminal is at a high level, and turns them off when the output terminal is at a low level.

An input terminal 40a of the logic circuit 40 is connected to one input terminal of an exclusive O7 circuit 40e and one input terminal of a NOR circuit 40f. The input terminal 40b is connected to the other input terminal of the exclusive circuit 40e and the other input terminal of the NOR circuit 4Of.

The output terminals of both circuits 40e and 40f are respectively connected to both input terminals of OR circuit 40g. OR circuit 40g
The output terminal of is connected to the output terminal 40c of the logic circuit 4o and the input terminal of the inverter 40h.
The output terminal of is connected to the output terminal 40d of the logic circuit 4o.

The table below shows the position of the dustproof cover 2, the position of the focal length selection member 5, and the switch SW that changes depending on these positions.
I, the state of S12, the input terminal 40a of the logic circuit 4o,
40b, level of output terminals 40c and 40d, switch 5
W7a, 5I17b, 5W8a, 5W8b (7) The relationship between the states and the positions of the main optical system 3 and the sub optical system 4 is summarized.

Adjustments to be made when assembling the focal length switching type camera having the above configuration will be explained.

This adjustment can be roughly summarized into the following three categories.

゛■Adjusting the extension amount necessary to switch the photographing optical system 3.4 from the wide-angle area to the telephoto area to a predetermined value■Photographing optical system 3
．． 4 and the film surface to a predetermined value. Adjustment to match the phase between the photographic optical systems 3 and 4 and the cam member 53, etc. that follow them. It is.

(8) The base plate 10, the main optical system 3, the sub-optical system 4, the sub-optical system insertion/removal mechanism, etc. attached to the base plate 10 are considered to be one unit, and are attached to a predetermined jig. This jig includes a guide member that supports the plywood 10 so that it can be guided in the optical axis direction of the main optical system 3;
It includes a collimator for inspecting the focal length of the main optical system 3 and the combined optical system 3.4.

■The main optical system 3 alone constitutes the photographing optical system, and the main optical system is set in a wide-angle state, using a collimator so that the object at the first predetermined distance (for example, at infinity) is imaged on a plane corresponding to the film plane. The position of the optical system 3, that is, the base plate lO is adjusted.

The base plate 10 is advanced by a predetermined amount from the adjustment positions m and n, and the sub-optical system 4 is inserted behind the main optical system 3, and the zero plywood 10 is advanced by a predetermined amount to create a telephoto state.

Then, the air distance between the main optical system 3 and the sub optical system 4 is adjusted using a collimator so that the object at a second predetermined distance (for example, infinity) is imaged on a plane corresponding to the film plane. . Since the sub-optical system 4 is held by a support tube 4e screwed onto the drive member 27, the sub-optical system 4 can be moved in the optical axis direction by rotating the support tube 4e, and the main optical system You can adjust the air spacing between 3 and 3.

An example of a specific procedure for adjustment (2) is as follows.

③ Incorporate the unit after completing the adjustments in Steps to ② above into the camera, and insert it into the optical path of the collimator.

V, as shown by the solid line in FIG. 2, a wide-angle photographing optical system is configured only with the main optical system 3, and a spur gear 52b and a reduction gear 53
The cam member 53 is in a disengaged state, that is, the cam member 53
and the photographing optical system 3.4 is disconnected.

(2) After roughly adjusting the base plate 10 that has been supplied with power to the motor 12 to the approximate position, the power supply to the motor 12 is stopped. Then, the main optical system 3 finely adjusts the position of the base plate 10 using a collimator so that the object at a third predetermined distance (for example, 2.4 mm) is imaged on the film plane. Figure 2,
This is done by loosening the set screw 15a shown in FIG. 10, fitting the tip of a screwdriver into the slot 15c of the guide shaft 15, and rotating the guide shaft 15. As is clear from FIG. 10, the guide shaft 15 itself cannot move in the axial direction, so it rotates relative to the gear 14, and since the motor 12 is stopped, the gear 14 also does not rotate. The plate 10 moves back and forth in the optical axis direction. When the adjustment is completed, the set screw 15a is tightened to fix the guide shaft 15.

An example of a specific procedure for the adjustment in (2) is as follows.

■0 Next, the adjustment to determine the positional relationship of the cam member 53 (cam plate 71) with respect to the photographing optical system 3.4 and the cam lever 73 is carried out.The state in which the adjustment described in (■) above is completed, that is, the main optical system 3 is in the third position. The spur gear 52b and the reduction gear 53 are in a position to form an image of a subject at a predetermined distance on the film surface.
a, so that the cam member 53 and the photographing optical systems 3 and 4 can interlock with each other. Loosen the screws 71b shown in FIGS. 2, 13, and 14, and remove the cam member 53 (cam plate 71
) can rotate within the range of the elongated hole Via. As shown in FIG. 13, the driven end 73 of the cam lever 73
The mark attached to a and the mark attached to the cam plate 71 are made to face each other, and the screw 71b is fastened. The index on the cam plate 71 indicates the position that the cam plate 71 should take with respect to the driven end 73a when the automatic focus adjustment device detects that the subject is at the third predetermined distance. Once completed, the position of the cam member 53 (cam plate 71) with respect to the photographing optical system 3.4 and the cam lens (-73) is determined.

10 Next, the position of the encoder printed circuit board B2 with respect to the photographing optical system 3.4 is adjusted. First, the screw 82b is loosened so that the encoder printed circuit board 82 can rotate around the shaft 50 within the range of the elongated hole 82a. Then, when the photographing optical system 3.4 is focused on the subject at the third predetermined distance, the encoder printed circuit board B2 is positioned at the position to be taken, and the screw 82b is fastened. The position that this board 62 should take is the position where the photographing optical system position signal indicating that the photographing optical system is focused on the subject at a third predetermined distance is provided on the bottom surface of the board 82. This is the position obtained from the pattern.

As described above, when the driven end 73a of the cam lever 73 faces each of the wide-angle infinity point a, the telephoto infinity point f, and the telephoto infinity point g of the cam plate 71, the wide-angle photographing optical system is activated. The camera accurately focuses on objects at infinity in the same state, close-up in the same state, infinity in the telephoto state, and close-up in the same state, and accurate photographic optical system position signals are obtained from each of the sliding contact patterns. can get.

Next, a signboard is placed at the predetermined subject distance (for example, 2.4 m) on the optical axis of the main optical system 3 where the AF optical system is adjusted, and the light emitting element 8C is energized and the light receiving element 8d is Make it incident. Then, the eccentric pin 75c is rotated to adjust the direction of the light emitting element 8C so that the output of the light receiving element 8d is in a predetermined focus detection state.

Since the wide-angle area C and the telephoto area of the cam plate 71 are separated by the rotation angle corresponding to the first predetermined amount of extension, the entire area of the cam surface of the cam plate 71 can be adjusted by only the above adjustment. This means that it has been completed.

Each adjustment is now complete.

Next, the operation will be explained.

(1) As shown in Figure 3, the dustproof cover 2 is in the open position,
When the focal length selection member 5 is at the telephoto position and the main optical system 3 is already at the extended position, both switches SWI and SW2 are in the ON state, so that the input terminal 40 of the logic circuit 40
Both a and 40b are at the old gh level. The output terminals of exclusive OR circuit 40e and NOR circuit 40F are Low.
level, and the output terminal of the OR circuit 40g also becomes low level. Output terminals 40c and 40d of the logic circuit 40 are at Low and High levels, respectively.

As a result, the switches 5W7a and 5W7b shown in FIG.
is turned off, and switches 5W8a and 5W8b are turned on.

Since the main optical system 3 is in the extended position, switch SW3.

SW4 and SW5 are in ON, OFF, and ON states, respectively.

Since the switches 5W7a and 5W7b are OFF, the first path is not formed, and since the switch SW4 is OFF, the second path is not formed.

In this case, the main optical system 3 is at the feeding position, and the sub optical system 4 is at the eighth position.
As shown in the figure, they are at rest at the fully inserted position where they are fully engaged with the positioning means, and both optical systems constitute a composite optical system whose focal length is a telephoto lens.

Since the switches 5W1a and 5115 are both ON, the autofocus Wfr1/shutter control circuit 31 is in an operable state, and photography with the telephoto optical system is possible.

Further, the finder optical system is also in a telephoto state as shown in FIG. 15 in which the first objective lens 5B is positioned in front of the second objective lens 57.

When a shooting start operation is performed by pressing a release button (not shown), the motor 12 receives power through the third path and rotates, moving the optical system 3.4 in the optical axis direction between the infinity and close range positions in the telephoto range. to adjust the focus. Main optical system 3, sub optical system 4, and base plate 1 for focus adjustment for telephoto shooting.
0 is displaced back and forth.

Photographing in the telephoto state and photographing in the wide-angle state are almost the same, and the method of photographing will be explained later for the wide-angle state.

As shown in FIG. 15, when the cam member 53 rotates with the rotation of the motor 12 for focus adjustment in the telephoto range, the vertical rod 58e of the linear holder 58 is inserted into the split groove of the variable power swing lever 59. The starting teeth 53b of the cam member 53 and the starting teeth 55b of the switching drive S member 55 are spaced apart from each other, and the starting teeth 53b of the cam member 53 are separated from the starting teeth 55b of the switching drive S member 55. The driven pin 59a of the double swing lever 58 is connected to the first circumferential groove 54a of the cam groove 54 of the cam member 53.
, and the driven pin 59a does not come into contact with the side wall of the first circumferential groove 54a, so the finder optical system will not be switched or vibrated due to operation.

(2) When the focal length selection member 5 is switched from the telephoto state shown in FIG. 3 to the wide-angle position, the switch S%12 is set to OF.
F state is entered, and the input terminal 4 of the logic circuit 40 in FIG.
0b becomes Low level. Since the output terminal of the exclusive logic circuit 40e becomes the old gh level, the output terminal of the OR circuit 40g is inverted to the old gh level, and the logic circuit 4
The output terminals 40c and 40d of 0 are old GH and Lo, respectively.
Invert to W level.

As a result, the switches 5W7a and 5W7b shown in FIG.
t*apt tona v, /C each 5W8a, 5W8b,
becomes OFF.

The main optical system 3 is in the extended position, and the switch S%13.51
14.

Since the motor 8w5 is in the ON, OFF, 0Ncy state and the switches 5W7a and 5W7b are ON, the first path is formed and the motor 12 is started. Therefore, the main optical system 3 begins to be displaced from the extended position toward the retracted position.

The sub optical system 4 is displaced in the optical axis direction from the complete insertion position (shown in FIG. 8) where it engages with the positioning means 28 during the initial rotation of the motor 12, and moves to the incomplete insertion position where it does not engage with the positioning means 28. Displace. This displacement in the forward axial direction causes the cam 26a to
This is done by rotating counterclockwise from the state shown in FIG. 2 and pushing up the sliding contact portion 27c of the drive member 27 in the first slope section B.

The cam 28a contacts the sliding portion 2 of the drive member 27 in the first slope section B.
7c, the engaging portion 27a of the drive member 27 comes into contact with the first engaging portion 30c from a position facing the first small diameter portion 30b of the blocking plate 30a. and,
Before the sub optical system 4 reaches the incomplete insertion position, the engaging portion 27e
is disengaged from the first engaging portion 30c, and the second small diameter portion 3
It reaches a state opposite to 0d.

FIG. 12 shows the state immediately before that.

When the sub optical system 4 reaches the incomplete insertion position, the positioning means 28
When the engaging part 27e is disengaged from the small diameter part 30d and the engaging part 27e faces the small diameter part 30d, the driving member 27 can swing in the direction transverse to the optical axis, so as the controlling motor 12 rotates, the sliding part 27c It is pushed by the first slope section B and swings counterclockwise in a plane that cuts the optical axis of the main optical system 3.

At this time, as shown in FIGS. 8 and 9, the end surface of the small cylinder 4C of the sub-optical system 4 slides on the back surface 10s+ of the base plate 10, which is perpendicular to the optical axis of the main optical system 3, in the same direction. When the main optical system 3 approaches the retracted position, the free end 2 of the drive member 27
7d comes into contact with the locking member 10k and is prevented from swinging,
The sub optical system 4 is a circular hole 10! It reaches the incomplete evacuation position where it is not inserted into L.

Since the motor 12 continues to rotate after that, the drive member 2
The sliding contact portion 27c of No. 7 ascends the first slope section B of the cam 28a and reaches the second flat section C. At this time, the blocking plate 30
The second engaging portion 30c of the drive member 27 is the engaging portion 27e of the drive member 27.
be associated with

Subsequently, the sliding contact portion 27c slides down the second slope section. At this time, due to the action of the spring 30, the sliding contact portion 27c may slide down along the second slope section and rotate clockwise, causing the sub optical system 4 to move back toward the insertion position.
This backward movement is prevented by the engagement between the second engaging portion 30e and the engaging portion 27e.

As the sliding contact portion 27c slides down along the second slope section, the front end surface of the bearing portion 27a touches the flange 10 as shown in FIG.
Since the sliding contact portion 27c is in contact with the cam 28a, the sliding contact portion 27c is separated from the cam 28a and faces the first flat section A, but reaches a state in which it does not come into contact with the first flat section A.

Due to the accompanying displacement of the driving member 27 in the optical axis direction, the small cylinder 4c of the sub-optical system 4 is inserted into the circular hole 10M of the base plate lO, and the end surface 4b of the holding cylinder 4a is inserted into the circular hole 10! It comes into contact with the edge of L and reaches the fully retracted position. At this time, the main optical system 3.

The retraction position has been reached. At this time, the engaging portion 27e is disengaged from the second engaging portion 30e, and the first small diameter portion 3
It faces 0b.

Note that after the front end surface of the bearing portion 27a comes into contact with the collar 10i and the driving member 27 stops displacing in the optical axis direction,
A spring 29 supplies a biasing force for inserting the sub optical system 4 into the circular hole 10IL.

When the main optical system 3 reaches the retraction position, as shown in FIG.
'L so h OFF, ON.

It will be in the ON state. When switch SW3 turns OFF.

The first path is cut off and power supply to the motor 12 is stopped. Therefore, the main optical system 3 stands still at the retracted position, and the sub optical system 4 stands still at the completely retracted position.

The optical system consists of only the main optical system 3, and its focal length is in a wide-angle range. Also, since the switches SWI and S%15 are both ON, the automatic focus adjustment Φ shutter control circuit 3
1 is in an operational state, allowing shooting in a wide-angle area.

Further, in response to the change in the above state, the finder optical system is switched as follows by the finder switching mechanism. That is, the first finder optical system 6 is moved from the insertion position to the retracted position.

Since the base plate 10 moves back a lot due to switching from the telephoto state to the wide-angle state, the rack 51 moves back a lot, and the rack teeth 51b, pinion 52a, transmission shaft 52. Spur gear 52
b. The cam member 53 is largely rotated by the path of the reduction gear 53a.

The rotation of the cam member 53 causes the activation tooth 53b to push the activation tooth 55b of the fan-shaped portion 55d of the switching drive member 55, and further, the driving tooth 53c and the driving tooth 55c engage with each other. @ 55b and drive tooth 55
There is one tooth missing between c and c, so they start meshing smoothly without interference.

Then, as shown in FIG. 16, the switching drive member 55 is rotated, so the tip of the engagement rod 57c is pushed against the first cam surface 55e, and the second objective lens 57 is rotated about the pivot shaft 57a. When the engagement rod 57c is rotated counterclockwise by a set angle and the tip of the engagement rod 57c reaches the second cam surface 55f, the second objective lens 57 is held at a constant angle.

In synchronization with the angular displacement of the second objective lens 57, the first objective lens 5B draws an arc around the cam part 55g together with the switching drive member 55, and brushes the edge of the second objective lens 57 when it faces the front. and move.

At this time, the 152 objective lens 57 is housed in a substantially trapezoidal space formed adjacent to the narrowed part of the finder optical system.

After that, the driven pin 59a of the variable power swing lever 58 is moved to the cam groove 5.
The driving groove 54b is reached from the first circumferential groove 54a of No. 4. Then, the variable power swing lever 53 rotates clockwise about the pivot shaft 511b, thereby pushing the linear holder 58 forward via the split groove 59e, the driven rod 58e, and the linear coupling arm 58d.

When the straight holder 58 is pushed forward, the engagement rod 57c
Since the tip of the switching drive member 55 is removed from the second cam surface 55f, the second objective lens 57 faces forward as before, and the linear holder 58 and the second objective lens 57 face forward without interfering with the cam portion 55g. 1 objective lens 58 and is pushed out to the original position of the first objective lens 56, and the variable power swing lever 59 is inverted and held at the wide-angle position by the toggle spring 59d, and becomes the state shown in FIG. 2, and the wide-angle finder Becomes an optical system.

Simultaneously with the switching of each prefecture, the AF system and the distance display in the finder are also switched.

That is, as shown in FIG. 18, in the telephoto state, the driven end 73a of the cam lever 73 is in the telephoto region of the cam surface of the cam plate 71, but when the cam member 53 rotates, the driven end 73a is in the telephoto region. It passes through the telephoto infinity point f, which is the focusing operation start position, passes through the standby area e, which is a circumferential surface, and reaches the transition area d, enters the wide-angle area C, switches to the wide-angle state, and finally reaches the 17th point As shown in the figure, the driven end 73a is located at the wide-angle infinity point a, which is the focusing operation start position in the wide-angle region C.

As a result, the light projecting direction of the light projecting element 8C becomes infinity, which is substantially parallel to the optical axis of the main optical system 3.

Further, as the plywood lO retreats when switching from telephoto to wide-angle, the direct drive cam plate 17 also retreats integrally, resulting in the state shown in FIG. 2, and the driven pin 82a engaged with the cam groove 17b is displaced. The pointer 83e that was visible in the finder in the telephoto state disappears from the field of view, and the pointer 83d comes into view.

In response to a shooting start operation using a release button (not shown), the motor 12 receives power through the third path and rotates, causing the main optical system 3 to rotate.
is advanced from the infinity position in the wide-angle area shown in FIG. 2 to the close position to adjust the focus.

As the motor 12 rotates, the gear 1 is
4 rotates, and since the gear 14 cannot move back and forth relative to the base plate 10, it moves along the guide shaft 15 together with the base plate 1G.

The movement of the plywood lO is transmitted to the pinion 52a via the rack teeth 51b of the rack 51, and from the transmission shaft 52 to the spur gear 52.
b. The rotational motion is converted into rotational motion and transmitted to the cam member 53 via the reduction gear 53a.

Since the gear 50b biased by the spring 50c is meshed with the reduction gear 53a, backlash during meshing is suppressed and transmission is performed with high precision, and the biasing force of the spring 50c helps the forward movement of the photographing lens. Immediately set the shooting lens to A.
Perform F action.

When the reduction gear 53a rotates, the cam member 53 also rotates integrally, the driven end 73a follows the cam surface of the cam plate 71, and the cam lever 73 is rotated in accordance with the shooting distance. Since wide-angle photography is being performed, the driven end 73a moves from the infinity point a of the wide-angle area C toward the closest point.

For telephoto shooting, from the infinity point f in the telephoto area to the closest point g
move towards.

The displacement of the cam lever 73 results in a tilting of the light projecting element 8c, and the light beam from the light projecting element 8C is swung from infinity toward close range. When this light beam hits the subject, it is reflected there and returns to the light receiving element 8d.

The change in the output state of the light receiving element 8d at this time is calculated by the distance measuring device, and the motor 12 is stopped when the focus detection output reaches a predetermined focus detection output. At this time, the photographing optical system (main optical system 3) is focused on the subject.

Upon completion of focusing, the light emitting element 8C also stops emitting light, and photography continues.

Since there is inertia in the cam member 53 and other parts, and there is a deviation between the signal and the stopping distance, the cam surface of the cam plate 71 is designed to take this into consideration.

When the plywood 10 moves back and forth, the cam groove 1 of the direct-acting cam plate 17? b, the slide lever 8 is moved through the driven pin 82a.
3 is moved in the horizontal direction, and the pointer 83d moves within the field of view of the finder, so that the approximate distance to the subject can be determined by the mark in the field of view indicated by the pointer while looking through the finder. For telephoto shooting, the pointer 83e has a similar function.

When the release button is released, the motor 12 reverses and the main optical system 3
is retracted to the infinite position in the wide-angle area, and the cam lever 73
The driven end 73a of the switch SW3 faces the infinity point a and detects the 0 position in preparation for the next photographing.

This is done by SW4 and SW5.

During the rotation of the motor 12 for focus adjustment in the wide-angle area, the sliding portion 27c of the drive member 27 only faces the first flat section A and does not contact it, so the drive member 27 does not move and the sub optical system 4 remains in the fully retracted position.

In the wide-angle state, even when the cam member 53 is rotated for focus adjustment, the vertically moving rod 58e of the linear holder 58 is attached to the inner wall of the split groove 59e of the variable magnification swinging lever 59 and the finder housing 1a due to the urging force of the vertically moving rod 58e of the linear holder 58. It is held between the front end of the guide groove 1f and the front end of the guide groove 1f.

The driven pin 59a of the variable power swing lever 59 moves within the range of the second circumferential groove 54c of the cam groove 54 of the cam member 53, and the driven pin 59a is moved within the range of the second circumferential groove 54c of the cam groove 54 of the cam member 53 so that the driven pin 59a does not come into contact with the side wall of the second circumferential groove 54c. Since the driven pin 59a moves within the area of the second circumferential groove 54c of the cam groove 54, the variable power swing lever 59 does not swing, and the fan-shaped portion 55d of the switching drive member 55 is driven. The end of the tooth 55c is the sliding contact edge 53 of the cam member 53.
Since it is in sliding contact with d, the second objective lens 57 is not displaced and is stably held.

(3) When the dustproof cover 2 is moved from the open position to the closed position from the telephoto state, the switch SWI turns OFF.
The input terminal 40a of the logic circuit 40 becomes Low level,
The output terminal of the exclusive O7 circuit 40e becomes the old gh level. The following operation is similar to (2), and even though the three-point distance selection member 2 is in the telephoto position, the main optical system 3 is displaced from the extended position to the retracted position, and the sub optical system 4 is fully inserted. position toward the fully retracted position.

When the main optical system 3 is displaced to the retracted position, the dustproof cover 2 can be displaced to the closed position.

When the dustproof cover 2 reaches the closed position, the switch 5W1a, which is in phase with the switch Sw1, is turned OFF, so power supply to the autofocus 7IJWI/shutter control circuit 31 is cut off, and photographing is no longer possible.

Similarly, the finder optical system, AF system, etc.

A switch is made from the telephoto position to the wide-angle position.

(4) When the dustproof cover 2 is moved from the wide-angle state to the closed position, the switch 5W1a, which is in phase with the switch Swl.

Automatic focus because it is OFF! The power supply to the l1frI/shutter control circuit 31 is cut off, making photography impossible.

(5) When the focal length selection member 5 is switched from the wide-angle state shown in FIG. 4 to the telephoto position, the switch SW2 is turned on, and the input terminal 40a of the logic circuit 40 shown in FIG.
, 40b are both at the old GH level. The output terminals of the exclusive OR circuit 40e and the NOR circuit 40f are both Lo.
Since the level is W, the output terminal of the OR circuit 40g is Lo.
Inverted to w level, output terminals 40c, 4 of logic circuit 40
0d is inverted to Low and High levels, respectively.

This causes the switch SW? shown in FIG. a, 5W7
b is OFF, and switches 5W8a and 5W8b are OFF.
It becomes N.

Since the main optical system 3 is in the retracted position, the switch 813.

SW4 and S15 are in the OFF, ON, and ON states, respectively.

Since XE/f 5W8a and 5W8b are ON and SW/f-5It14 is ON, the second path is formed and the motor 12 begins to rotate in the opposite direction to that in (2). Therefore, the main optical system 3 begins to be displaced from the retracted position toward the extended position.

With this initial rotation of the motor 12, the sub optical system 4.

It is displaced in the optical axis direction from the completely retracted position shown in FIG. 9, exits the circular hole 101, and is displaced to the incompletely retracted position.

This displacement in the forward axial direction is caused by the rotation of the cam 26a and pushing up the sliding contact portion 27c of the drive member 27 at the second slope section.

Before the cam 28a pushes up the sliding contact portion 27c of the driving member 27 at the flS2 slope section, the engaging portion 27 of the driving member 27
e comes into contact with the second engaging portion 30e from a position facing the first small diameter portion 30b of the blocking plate 30a. Then, before the sub optical system 4 reaches the incompletely retracted position, the engaging portion 27
e disengages from the second engaging portion 30e and reaches a state where it faces the small diameter portion 30d of m2. Figure a811 shows the state immediately before this.

Thereafter, the sub optical system 4 reaches the incompletely retracted position and the circular hole 10
When removed from iL, the drive member 27 becomes swingable in a direction transverse to the optical axis of the main optical system 3.

As the motor 12 continues to rotate, the sliding portion 27c is pushed in a direction across the optical axis by the second sloped section, so the drive member 27 swings in the same direction, causing the small cylinder 4c of the sub optical system 4 to move. The end surface moves from the incompletely retracted position to the incompletely inserted position while sliding on the back surface 10 layers of the base plate IO.

When the main optical system 3 approaches the extended position, the free end 27d of the drive member 27 comes into contact with the locking member 10j to prevent its swinging, and the sub optical system 4 stops at the incompletely inserted position. After that, the motor! Since the cam 2 continues to rotate, the sliding portion 27c of the drive member 27 ascends the second slope section of the cam 2Ela and reaches the second flat section C.

At this time, the first engaging portion 30c of the blocking plate 30a engages with the engaging portion 27e of the drive member 27.

Subsequently, the sliding contact portion 27c slides down the first slope section B as shown in FIG. At this time, there is a risk that the drive member 27 will rotate counterclockwise along the first slope section B due to the action of the spring 30, and the sub optical system 4 will move back toward the retracted position. The first engaging portion 30c engages and is blocked.

While the sliding contact portion 27c is sliding down the second slope section, the front end surface of the bearing portion 27a comes into contact with the collar 10i, so that the sliding contact portion 2? c is separated from the cam 28a and reaches a state where it faces the first flat section A but does not come into contact with it.

As a result of the displacement of the drive member 27 in the optical axis direction, the small cylinder 4G of the holding cylinder 4a of the sub-optical system 4 comes into contact with the guide surface 28b of the positioning means 28, and is guided by the guide surface 28b.
8a, the end surface 4b of the holding cylinder 4a comes into contact with the contact surface 28c of the positioning means 2, and the positioning in the sub optical system 4 is completed when the fully inserted position shown in FIG. 8 is reached. At this time, the main optical system 3 has reached the feeding position. Also, at this time,
The engaging portion 27e is disengaged from the first engaging portion 30c,
It faces the first small diameter portion 30b.

Note that after the drive member 27 stops displacing in the optical axis direction due to the bearing portion 27a coming into contact with the collar 10i, the sub optical system 4
A spring 28 provides a biasing force for engaging the positioning means 28 .

When the main optical system 3 reaches the extended position, the switches SW3 and SW4.5115 are in the ON, OFF, and ON states, respectively, as described in (1). When the switch S 4 is turned off, the second path is cut off and power supply to the motor 12 is stopped. Therefore, as shown in FIG. 2, the main optical system 3 is stationary at the extended position and the sub optical system 4 is stationary at the fully inserted position, forming a composite optical system whose focal length is in the telephoto range. Also switches 5W1a, 8w5
Since both are ON, the automatic focus adjustment/shutter control circuit 31 is in an operable state, and photography with the telephoto optical system is possible.

In response to the above switching operation, the finder optical system is switched from the wide-angle state to the telephoto state.

That is, when the main optical system 3 and the sub-optical system 4 are switched to the telephoto state, the base plate 10 moves forward significantly, so that the cam member 53 rotates significantly, contrary to the above.

As a result, the driven pin 59a of the variable power swing lever 59 reaches the drive groove 54b from the second circumferential groove 54c of the cam groove 54, and the variable power swing lever 58 changes from the state shown in FIGS. 14 and 15(C). rotates counterclockwise to pull back the second objective lens 57 and the linear holder.

When the second objective lens 57 and the linear holder 58 move back, the tip of the retaining rod 57c moves to the cam portion 55 of the switching drive member 55. comes into contact with the second cam surface 55F of the second objective lens 5.
7 is held in an angularly inclined state about the swing axis 57a.

In synchronization with this, the driving teeth 53c mesh with the driving teeth 55c, the switching driving member 55 is rotated clockwise, and the housed first objective lens 5B is rotated clockwise in an arc around the swing axis 55a. Rotate to.

Next, the tip of the engagement loft 57c reaches the first cam surface 55e of the cam part 55g, and finally the second objective lens 57 faces the front, and the straight holder 57 faces the front of the second objective lens 57. It returns to the telephoto state shown in Figure 1-5.

Similarly, the distance display in the finder is switched from the wide-angle state to the telephoto state by an operation opposite to that in (2) above.

(6) When the dustproof cover 2 is moved toward the open position from the state where the dustproof cover 2 is covered in the telephoto state, the switch SW
1 becomes ON, and the input terminal 40a of the logic circuit 40
, 40b are both at the old gb level. Below is the above (5)
The operation is the same as described in .

According to this embodiment, a wide-angle area a, a transition area d, a standby area e,
Since each cam surface in the telephoto region is integrally formed on the cam plate 71 made of synthetic resin, manufacturing and assembly are simplified.

Further, since the relative position between the cam plate 71 and the photographing optical system can be adjusted by the adjustment mechanisms 71a and 71b, high focus adjustment accuracy can be obtained.

Since the wide-angle area a and the telephoto area of the cam plate 71 are integrally molded, the relative position of the two areas cannot be changed. This can be done by adjusting the interval.

In the above embodiment, during automatic focus adjustment prior to photographing, the photographing optical system was moved from the position where the subject was focused at infinity to the position where the subject was in focus at a close distance, but the present invention is not limited to this. It can also be applied to configurations in which the renormalization is carried out in the opposite direction.

Furthermore, in the above embodiment, the photographic optical system can switch between two types of focal lengths: wide-angle and telephoto; however, the present invention is not limited to this, and can also be applied to configurations where the focal length can be switched between three or more types. be.

In addition, the biasing spring is not limited to a thinly wound spring wound around a gear, but may be any spring that biases the photographic optical system in the forward direction. It may be provided at a location that acts on the gear transmission mechanism between them.

"Effects of the Invention" According to the automatic focus WR adjustment device according to the present invention, since a biasing spring that biases the photographing optical system in the forward movement direction is provided in the middle of the motion transmission system, the photographing optical system can be quickly activated during AF. In addition, backlash in the gear transmission mechanism is eliminated, allowing the photographing optical system and the interlocking mechanism to interlock with high precision. Furthermore, since the load on the motor during AF is reduced, the power consumption of the motor is reduced. Therefore.

Accordingly, the amount of power supplied to other electrical devices operating during AF (for example, the light emitting element of active triangulation AF as in this embodiment) can be increased.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, in which Fig. 1 is a detailed view of a mechanism for removing backlash, Fig. 2 is a perspective view schematically showing the internal mechanism of the camera, and Fig. 3 is a perspective view of the camera. 4 and 5 are plan views of the camera, FIG. 6 is a vertical sectional view of the camera, FIG. 7 is a horizontal sectional view of the camera, and 8'' and 9 The figure is a detailed sectional view of the main part of the sub optical system insertion/removal mechanism, FIG. 10 is a schematic sectional view of the main part, and FIGS. 1351J is a plan view of the automatic focusing mechanism, FIG. 14 is a vertical sectional view, FIGS. 15 and 16 are plan views of the finder optical system switching mechanism,
Figures 7 and 18 are plan views of the vicinity of the cam plate, Figure 19 is a motor control circuit diagram for driving the optical system, Figure 20 is a logic circuit diagram that controls the operation of the motor control circuit, and Figure 21 is a cam diagram. It is. 1...Camera body 1a...Finder storage section 3...Main optical system 4...Sub-optical system 10.
...Bedplate 12...Motor -26
...Cam gear 27...Drive member 51...
・Rack 53a...Reduction gear 50c...
-(Biasing) spring 53...Cam member 55...Switching drive member 56...First objective lens 57...Second objective lens 81...Detection brush plate 82...Printed circuit board for encoder Figure 1 Figure 3 Figure 4 Ug1 Figure 5 Figure O Figure 1/Figure 1Z Figure

Claims (1)

[Scope of Claims] An automatic system comprising an electric drive source, a photographing optical system that is reciprocated in the optical axis direction by the drive source, and an interlocking mechanism that is driven by the drive source and interlocks with the photographic optical system. Automatic focus adjustment is performed by moving the photographing optical system forward from the original position in response to the generation of a signal to start focus adjustment, and the photographing optical system is moved back to the original position in response to the generation of a signal to end automatic focus adjustment. The automatic focus adjustment device includes a gear transmission mechanism that transmits the driving force of the electric drive source to the interlocking mechanism, and a biasing member, and the biasing member is configured to transmit the driving force of the electric drive source to the interlocking mechanism when the photographing optical system moves back. An automatic focusing device characterized in that energy is stored by an electric drive source to urge the photographing optical system in the forward movement direction and to eliminate backlash occurring in the gear transmission mechanism.