JPH073538B2 - Fiber optical system magnification switching device - Google Patents

Description

[Technical Field of the Invention] The present invention relates to a photographing optical system capable of moving straight in the optical axis direction for switching focal lengths and adjusting focus at each focal length, and a viewfinder capable of switching magnification. And a finder optical system magnification switching device for a focal length switching type camera having an optical system.

"Background of the Invention" In the camera as described above, it is necessary to switch the finder optical system corresponding to the switching of the photographing optical system.

In such a case, there is a zoom type finder optical system, but it has a drawback that the optical system becomes complicated and the cost becomes high.

Further, Japanese Utility Model Laid-Open No. 58-96523 discloses that the constituent elements of the finder optical system are replaced or inserted / removed in conjunction with the change of the focal length of the photographing optical system, but the operating mechanism is large and compact. There is a drawback that you cannot do it.

In Japanese Utility Model Laid-Open No. 58-126433, a finder optical system is made compact by using a large number of lenses, but this is problematic in terms of cost.

If you take out the operation of the photographic optical system and switch the finder optical system in conjunction, you can make it cheap and compact, but if you easily interlock it, you can remove it from the motion transmission section between the photographic optical system and the finder optical system. There was a possibility that light would enter and there would be a problem in light shielding.

"Object of the Invention" It is an object of the present invention to provide a viewfinder optical system magnification switching device which solves the above problems by taking out the operation of the photographing optical system with a simple mechanism and interlocking the viewfinder optical system. I am trying.

[Configuration of the Invention] In order to achieve such an object, in the present invention, a photographing optical system that can go straight in the optical axis direction for switching the focal length and adjusting the focus at each focal length, and a viewfinder that can switch the magnification. A focal length switchable camera having an optical system, comprising: a first rotating member that rotates in association with the straight movement of the photographing optical system via a single transmission shaft; and a second rotating member that is coaxial with the first rotating member. A finder magnification switching device comprising a finder optical system drive mechanism for converting the magnification of the finder optical system according to the rotation of a member, and connecting the photographing optical system and the finder optical system only by the transmission shaft. By interlocking and eliminating the interposition between them, the structure is simplified to facilitate light shielding and partitioning, and the resistance during motion transmission is minimized.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1 and FIG. 2, a focal length selection member 2 is provided on the rear surface of the camera body 1, and inside the camera body 1, a switch SW1 interlocked with a dust cover (not shown) and a focal length selection member. Switch SW2 interlocking with member 2
And are provided.

On the front side of the camera body 1, a main optical system 3 is provided so as to be displaceable in the optical axis direction (left and right direction in the drawing), that is, retractable and retractable. Inside the camera body 1, the sub-optical system 4 crosses the optical axis of the main optical system 3 between the position inserted into the light beam of the main optical system 3, that is, the photographing light beam and the position retracted from the light beam (first It is provided so that it can be displaced in the vertical direction in FIG.

A plurality of finder optical systems including a first finder optical system 5 and a second finder optical system 6 are provided above the camera body 1 by being housed in the finder housing portion 1a. As shown in FIG. 14, this finder optical system is an inverted Galilean type including a front group 5a and a rear group 5b.

The switch SW1 is set to be turned off when the dustproof cover covers the main optical system 3 and turned on when the front surface of the main optical system 3 is opened. The switch SW2 is turned on when the focal length selection member 2 is in the telephoto position.
And is set to OFF when in the wide-angle position.

FIG. 3 is a perspective view showing the main optical system displacement mechanism and the finder optical system switching mechanism of this embodiment.

This figure shows a state in which the main optical system 3 is at the extended position. An opening 10a through which a photographing light flux passes is formed in the central portion of the base plate 10.
Is provided in front of which a diaphragm / shutter device 11 and a main optical system 3 shown by a chain line are fixedly installed.
A motor 12 is fixedly installed on the upper back surface of the base plate 10. Both ends of the rotary shaft penetrate through both end faces of the casing of the motor 12 and project therefrom.

A bevel gear 12a (illustrated in FIG. 4) is fixedly mounted on one end of the rotary shaft. A bevel gear 13 axially supported by the base plate 10 is engaged with the bevel gear 12a, and a spur tooth portion of the gear 13 is engaged with a gear 14 also axially supported by the base plate.

A through hole is formed in the center of the gear 14, and a female screw whose center is the rotation center of the gear 14 is cut in the through hole. A male screw cut on the guide shaft 15 is screwed onto the female screw.

The guide shaft 15 extends in the optical axis direction, the end is fixed to the substrate 1c of the camera body 1, and the tip is inserted into the through hole 10b of the base plate 10 so as to be slidable in the axial direction. A bevel gear 12b is fixed to the other end of the rotation shaft of the motor 12.

This bevel gear 12b has a bevel gear 1 discontinued on the base plate 10.
6 meshes with each other, and an input gear 17a of the gear train 17 stopped by the base plate 10 meshes with the spur teeth of the gear 16.

A through hole is formed in the center of the output gear 17b of the gear train 17, and a female screw whose axis is the rotation center of the gear 17b is cut in the through hole. A male screw cut on the guide shaft 18 is screwed into the female screw. The guide shaft 18 extends in the optical axis direction, the end is fixed to the substrate 1c of the camera body, and the tip is inserted into the through hole 10c of the base plate 10 so as to be slidable in the axial direction.

The amount and direction of rotation of the gears 14 and 17b relative to a certain amount of rotation of the motor are set to be equal, and the conditions for screwing the gear 14 and the guide shaft 15 and screwing the gear 17b and the guide shaft 18 are also set. Are set equal. A guide shaft 19 extending in the optical axis direction is also planted in the substrate 1c. The guide shaft 19 is axially slidably inserted into the through hole 10e of the overhanging portion 10d and the through hole 10f of the base plate 10, which are provided on the back surface of the base plate 10.

With this structure, when the motor 12 rotates, the gear 14
It is greatly decelerated by the screwing of the guide shaft 15 and the screwing of the gear 17b and the guide shaft 18, and the base plate 10 is parallelly moved in the optical axis direction while being perpendicular to the optical axis, and is fixed to it. The main optical system 3 and the diaphragm / shutter device 11 are displaced in the optical axis direction between the feeding position and the feeding position.

A printed circuit board 20 is fixed to the right side surface of the base plate 10.
Conductor lands 20a to 20c are provided on the surface of this printed circuit board 20, and these are fixed to the camera body.
The two sliding contact pieces 21 to 23 are each slidable.
The sliding contact piece 21 and the conductor land 20a form a switch SW3, the sliding contact piece 22 and the conductor land 20b form a switch SW4, and the sliding contact piece 23 and the conductor land 20c form a switch SW5.

The switch SW3 is OFF when the main optical system 3 is at the feeding position, the switch SW4 is at the feeding position, and the switch SW5 is OFF when it is between the feeding position and the feeding position. Switch SW
3 and SW4 act as limit switches, and when the main optical system 3 is displaced to the retracted position or the retracted position, power supply to the motor 12 is cut off.

The switch SW5 is used when the main optical system 3 is at an intermediate position between the above two positions and a subject image cannot be formed on the film surface.
A switch for disabling shutter release, and a switch for cutting off power supply to a shutter control circuit 31 (shown in FIG. 8) described later.

The film 24 is arranged behind the photographing opening 1d opened in the substrate 1c.

FIG. 4 is a perspective view of the auxiliary optical system loading / unloading mechanism arranged on the back surface of the base plate 10.

In the figure, a reduction gear train 25, a cam gear 26, and a drive member 27 are axially supported on the back surface of the base plate 10, and the drive member 27 holds the sub optical system 4. Input gear of reduction gear train 25
25a meshes with the spur gear portion of the bevel gear 13, and the final gear 25b of the reduction gear train 25 meshes with the cam gear 26.

The cam gear 26 and the drive member 27 are coaxial with each other, and they are coupled to each other via a front cam 26a provided on the end surface of the cam gear 26.

The reduction gear 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 at the insertion position (shown by the solid line) inserted in the photographing light beam, and when the main optical system 3 is at the retracted position, the retracted position where the sub optical system 4 is retracted from the photographing light beam (shown by the chain double-dashed line) It is designed to be placed in.

FIG. 5 shows a sectional view of the auxiliary optical system mounting / demounting mechanism.

In the figure, the main optical system 3 is attached to the base plate 10 in front of the opening 10a.
A diaphragm / shutter device 11 is fixedly provided, and a positioning means 28 for the sub optical system 4 is formed behind the opening 10a.
The positioning means 28 is composed of an inner cylindrical surface 28a having the optical axis of the main optical system 3 as an axis, a guide surface 28b in the shape of a skirt, and a contact surface 28c orthogonal to the optical axis of the main optical system 3.

A holding cylinder 4a for integrally holding the sub optical system 4 can be engaged with the positioning means 28, and the sub optical system 4 is engaged at the time of the engagement.
Is aligned with the optical axis of the main optical system 3 in the extended position, and the sub optical system 4 is positioned at a predetermined position in the optical axis direction.

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

The drive member 27 is axially slidably supported by a fixed shaft 10g planted in the base plate 10 via a bearing portion 27a so as to be slidable in the axial direction. The drive member 27 has a circumferential groove 27 in which the sub optical system 4 is loosely fitted.
b is formed.

A collar 4d is provided on the entire outer circumference of the holding cylinder 4a of the sub optical system 4, and a coil spring 29 is inserted between the inner circumferential groove 27b and the collar 4d. The spring 29 serves to urge the sub optical system 4 brought to the insertion position in the direction of contacting the positioning means 28.

A cam gear 26 is also axially supported by the shaft 10g, and a sliding contact portion 27c provided at one end of a drive member 27 can slidably contact a front cam 26a formed on this end surface. Collars 10h and 10i are fixedly mounted on the shaft 10g so as to sandwich the bearing portion 27a, and a spring 30 is inserted between the collar 10h and the drive member 27. The spring 30 serves to press the sliding contact portion 27c of the drive member 27 against the cam 26a or press the front end surface of the bearing portion 27a against the collar 10i.

A locking member 1 for locking the free end 27d of the driving member 27 on the base plate 10
0j and 10k are planted, the locking member 10j locks the swing of the drive member 27 when the sub optical system 4 is brought to the insertion position, and the locking member 10k retracts the sub optical system 4. Locks the swing of drive member 27 when brought into position.

Further, near the end of the locking member 10k, a circular hole 10l into which the small cylinder 4c of the sub optical system 4 brought to the retracted position falls in a loosely fitted state.
Is provided.

FIG. 5 shows a state in which the sub optical system 4 is in the insertion position and in the complete insertion position in which the sub-optical system 4 is engaged with the positioning means 28. The sub optical system 4 also takes the following positions.

That is, although it is in the insertion position, it is pushed up by the front cam 26a and does not engage with the positioning means 28, that is, the incomplete insertion position, which is on the circular hole 10l, but its small cylinder 4c is pushed up by the front cam 26a. It is an incomplete retracted position where it has not fallen into the circular hole 10l, and a complete retracted position where the small cylinder 4c has fallen into the circular hole 10l.

FIG. 6 shows a cam diagram of the cam 26a. Cam 26a
Is the first flat section A where the rotation angle Θ is 0 to Θ1 and the head does not change at 0, and the head h is 0 from Θ1 to Θ2.
From the first slope section B that increases linearly from 1 to h1 and the second flat section C where the head h does not change at h1 from Θ2 to Θ3
And a second slope section D in which the head h decreases linearly from h1 to 0 from Θ3 to 360 °.

The cam 26a has three functions with respect to the sub optical system 4. The first is the action of displacing the sub optical system 4 in the optical axis direction of the main optical system 3 between the completely inserted position and the incompletely inserted position. The second is the action of displacing the sub optical system 4 in a direction crossing the optical axis of the main optical system 3 between the incompletely inserted position and the incompletely retracted position. The third is the action of displacing the sub optical system 4 in the optical axis direction of the main optical system 3 between the incomplete retracted position and the complete retracted position. Details will be described later.

FIG. 3 shows a viewfinder optical system switching mechanism. The first finder optical system 5 is at the insertion position.

As shown in the figure, a rack 51 is erected on the back surface of the base plate 10, and the rack 51 is mounted on a guide shaft 51a in which the base end is planted in the base plate 1c and the front part is loosely fitted to the base plate 10. You are being guided.

A rack tooth 51b engraved on the rack 51 is engaged with a pinion 52a fixed to the lower end of the transmission shaft 52, so that the rack 51
The pinion 52a and the pinion 52a form a conversion mechanism that converts the linear motion of the base plate 10 into a rotary motion.

Further, only the transmission shaft 52 connects the photographing optical system and the finder optical system switching mechanism, and the transmission shaft 52 penetrates a partition plate which partitions off the photographing optical system and the finder optical system from each other.

The spur gear 52b fixed to the upper end of the transmission shaft 52 is the cam plate 5
The reduction gear 53a fixed to 3 is meshed with the reduction gear 53a.

A cam groove 54 is formed on the upper surface of the cam plate 53, and an actuating tooth 53b, a drive tooth 53c continuous from the actuating tooth 53b with one tooth missing, and a sliding contact edge 53d are formed on the peripheral edge.

The switching drive member 55 is disposed near the cam plate 53 and the swing shaft 55a
It is provided so as to be pivotally supported in the finder storage section 1a via the. The switching drive member 55 is a fan-shaped portion having a start tooth 53b of the cam plate 53, a start tooth 55b corresponding to the drive tooth 53c, and a drive tooth 55c.
55d and a first radial direction formed around the swing shaft 55a.
The cam portion 55g includes a cam surface 55e and a second cam surface 55f, which is a circumferential surface, and a swing arm 55h radially extended from the swing shaft 55a.

Then, the first objective lens 56 is fixed to the tip of the support arm 55i extended upward from the tip of the swing arm 55h,
The first objective lens 56 constitutes a first finder optical system.

The switching drive member 55 is urged clockwise by a spring 55j stretched between the switching drive member 55 and a pin projecting from the finder housing 1a as viewed from above in FIG.

The second objective lens 57 forming the second finder optical system is swingably supported by the rectilinear frame 58 via the pivot shaft 57a, and the rectilinear frame 5
Reference numeral 8 is supported in the finder housing 1a so as to be able to move straight in the optical axis direction of the finder optical path.

A spring 58b is stretched between a locking pin 57b protruding downward from the second objective lens 57 and a locking pin 58a protruding downward from the rectilinear frame 58, and the second objective lens 57 is As viewed from above in FIG. 3, the locking pin 57b is urged in the clockwise direction and abuts on the lower side 58c of the rectilinear frame 58 and is held facing the front.

Further, an engagement rod 57c protrudingly provided on the lower end surface of the second objective lens 57 extends downward, and the tip end thereof engages with the cam portion 55g of the switching drive member 55. The rack 51, the transmission shaft 52, the cam plate 53, the switching drive member 55, the engagement rod 57c and the like constitute a second finder optical system drive means.

On the other hand, the rack 51, the transmission shaft 52, the cam plate 53, the switching drive member 55 and the like constitute the first finder optical system drive means.

A driven pin 59a protruding from the swing lever 59 is engaged with the cam groove 54 of the cam plate 53. The oscillating lever 59 has its base end pivotally supported by the finder housing 1a via a pivot 59b.
A toggle spring 59d for holding the swing lever 59 in the telephoto position and the wide-angle position is stretched between the pin 59c protruding further from the pivot 59b and the pin 1b fixedly mounted in the finder housing 1a. There is.

The cam groove 54 of the cam plate 53 includes a first circumferential groove 54a that does not move the driven pin 59a, a drive groove 54b that moves the driven pin 59a and rocks the rocking lever 59, and a first groove that does not move the driven pin 59a. It is constituted by two circumferential grooves 54c.

A substantially U-shaped split groove 59e is formed at the tip of the swing lever 59, and the split groove 59e is provided with a vertical motion extending downward from a linear motion connecting arm 58d protruding rearward from the rectilinear frame 58. Rod 58e
Is engaged with the tip of the.

The tip of the vertical movement rod 58e is further attached to the finder storage section 1a.
It is slidably engaged with a guide groove 1f formed in the.

FIG. 8 shows a motor control circuit for driving the optical systems 3 and 4 of this embodiment.

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

The first path is the positive pole of the power supply E-the switch SW3-the switch S.
W7a-motor 12-switch SW7b-negative electrode path of the power supply E. By supplying power through this path, the motor 12
Rotates to displace the main optical system 3 to the retracted position and the sub optical system 4 to the retracted position.

The second path is the positive pole of the power source E-the switch SW4-the switch S.
W8a-motor 12-switch SW8b-negative electrode path of the power supply E. By supplying power through this path, the motor 12
Rotates in the direction opposite to that of the first path to displace the main optical system 3 to the feeding position and the sub optical system 4 to the insertion position.

Here, the switches SW7a, SW7b, SW8a, and SW8b are semiconductor switches whose opening / closing is controlled by a logic circuit 40 (shown in FIG. 9) described later.

The third path is a path connecting the automatic focus adjustment / shutter control circuit 31 and the motor 12, and the output of the control circuit 31 causes the motor 12 to rotate in the forward / reverse direction to move the optical system back and forth in the optical axis direction. Focus on.

The power supply path of this control circuit 31 has switches connected in series.
SW1a and SW5 are inserted. The switch SW1a is a semiconductor switch controlled by the switch SW1 and opened / closed in the same phase as the switch SW1. The switch SW1a is turned on only when a dust cover (not shown) is in the open position. Switch SW5 is the main optical system 3
Is turned on only when is in the extended position and the retracted position (when the sub optical system 4 is in the completely inserted position and the completely retracted position). These prevent the automatic focus adjustment and the shutter from operating when the dust-proof cover and the optical systems 3 and 4 are in positions unsuitable for shooting.

FIG. 9 shows a logic circuit 40 which controls the operation of the motor control circuit of FIG. The logic circuit 40 includes a pair of input terminals 40a and 40b and a pair of output terminals 40c and 40d.
The input terminal 40a is between the switch SW1 and the ground resistance, the input terminal 40b is between the switch SW2 and the ground resistance, and the output terminal
40c is the control terminal of the above switches SW7a and SW7b, and the output terminal 4
0d is connected to the control terminals of the switches SW8a and 8b, respectively.

The input terminal 40a becomes High level when the switch SW1 is ON, that is, when the dust cover is in the open position, and the switch SW1
When 1 is OFF, that is, when the dustproof cover is in the closed position, Lo
w level. The input terminal 40b is provided when the switch SW2 is ON, that is, when the focal length selection member 2 is in the telephoto position.
It becomes High level, and becomes Low level when the switch SW2 is OFF, that is, when the focal length selection member 2 is in the wide angle position.

When the output terminal 40c is at high level, the above switches SW7a and SW7b
Both are turned on, and both are turned off when the level is low. Output terminal
40d turns on both switches SW8a and SW8b at High level
And turn it off at the low level.

The input terminal 40a of the logic circuit 40 is connected to one input terminal of the exclusive OR circuit 40e and one input terminal of the NOR circuit 40f. The input terminal 40b is connected to the other input terminal of the exclusive OR circuit 40e and the other input terminal of the NOR circuit 40f.

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

The following table shows the positions of the dustproof cover, the position of the focal length selection member 2, and switches SW1 and SW that switch depending on these positions.
2 state, input terminals 40a, 40b, output terminals 40c, 4 of logic circuit 40
The relationship among the level of 0d, the states of the switches SW7a, SW7b, SW8a, and SW8b, and the positions of the main optical system 3 and the sub optical system 4 is summarized.

(1) As shown in FIG. 1, when the dustproof cover is in the open position, the focal length selection member 2 is in the telephoto position, and the main optical system 3 is already in the extended position, both switches SW1 and SW2 are turned on. Since the input terminals 40a and 40b of the logic circuit 40 are both Hig
It becomes the h level. The output terminals of the exclusive OR circuit 40e and the NOR circuit 40f are at low level, and the output terminal of the OR circuit 40g is also at low level. Output terminals 40c, 4 of logic circuit 40
0d is Low and High level, respectively.

As a result, the switches SW7a and SW7b shown in FIG. 8 are turned off, and the switches SW8a and SW8b are turned on. Since the main optical system 3 is in the extended position, as shown in FIG. 3, the switches SW3, SW4,
SW5 is in the ON, OFF, and ON states, respectively. Switch SW7
Since a and SW7b are OFF, the above first route is not formed,
Since the switch SW4 is OFF, the second path is not formed either.

In this case, the main optical system 3 is at the feeding position, and the sub optical system 4 is at the fifth position.
As shown in the figure, they are stationary at the fully inserted position where they are completely engaged with the positioning means 28, and both optical systems form a synthetic optical system, and the focal length thereof is in the telephoto range. Since the switches SW1a and SW5 are both ON, the automatic focus adjustment / shutter control circuit 31 is in an operable state, and shooting with the telephoto optical system is possible. FIG. 1 shows the state at this time.

The motor 12 is rotated by receiving power from the third path in response to the shooting start operation, and displaces the optical systems 3 and 4 in the optical axis direction from the close-up of the telephoto region to infinity to perform focus adjustment. During rotation of the motor 12 for focus adjustment in this telephoto region, the front end surface of the bearing portion 27a of the drive member 27 is in contact with the flange 10i by the biasing force of the spring 30, so that the sliding contact portion of the drive member 27 is in contact. 27c
Faces only the first flat section A of the cam 26a and does not make contact therewith. Therefore, the sliding contact portion 27c does not become a load on the motor 12.

The finder optical system is also in the telephoto state as shown in FIGS. 10 and 14 (A) with the first objective lens 56 positioned in front of the second objective lens 57.

When the base plate 10 of both the main optical system 3 and the sub optical system 4 is displaced back and forth for focus adjustment in telephoto shooting, the transmission shaft 52 is rotated by the conversion mechanism including the rack 51 and the pinion 52a.

When the cam plate 53 is thereby rotated, the vertical movement rod 58e of the rectilinear frame 58 is located between one inner wall of the split groove 59e of the swing lever 59 and the rear end of the guide groove 1f provided in the finder housing 1a. The starter tooth 53b of the cam plate 53 and the starter tooth 55b of the switching drive member 55 are separated from each other, and the vertical movement pin 59a of the rocking lever 59 is aligned with the first circumferential groove 54a of the cam groove 54 of the cam plate 53. The vertical movement pin 5 moves within the range and is attached to the side wall of the first circumferential groove 54a.
Since the 9a does not touch, the finder optical system does not operate and do not switch or vibrate.

Further, since only the transmission shaft 52 and the vicinity thereof are rotated, the resistance is small and energy is not wasted.

(2) When the focal length selection member 2 is switched to the wide-angle position from the state shown in FIG. 1, the switch SW2 is turned off,
The input terminal 40b of the logic circuit 40 becomes Low level. Since the output terminal of the exclusive OR circuit 40e is at the High level, the output terminal of the OR circuit 40g is inverted to the High level, and the output terminals 40c and 40d of the logic circuit 40 are inverted to the High and Low levels, respectively.

As a result, the switches SW7a and SW7b shown in FIG. 8 are turned on and the switches SW8a and SW8b are turned off. Since the main optical system 3 is in the extended position, as shown in FIG.
4, SW5 is in ON, OFF, ON state respectively, and switch SW
Since 7a and SW7b are ON, the above first path is formed,
The motor 12 starts. Therefore, the main optical system 3 starts to be displaced from the feeding position toward the feeding position.

The sub-optical system 4 is displaced in the optical axis direction from the complete insertion position (shown in FIG. 5) in which the positioning means 28 is engaged by the initial rotation of the motor 12 to the incomplete insertion position in which it is not engaged. Displace. The displacement in the optical axis direction is due to the cam 26a rotating clockwise from the state shown in FIG. 3 and pushing up the sliding contact portion 27c of the drive member 27 in the first slope section B.

When the sub optical system 4 reaches the incompletely inserted position and is disengaged from the positioning means 28, the drive member 27 can swing in the direction traversing the optical axis. 27
The c is pushed by the first slope section B and swings clockwise in the plane crossing the optical axis of the main optical system 3.

At this time, the end surface of the small cylinder 4c of the sub optical system 4 swings in the same direction while sliding on the back surface 10m of the base plate 10 which is perpendicular to the optical axis of the main optical system 3. When the main optical system 3 approaches the retracted position, the free end 27d of the drive member 27 comes into contact with the locking member 10k and its swing is prevented, and the sub optical system 4 does not insert into the circular hole 10l. To reach.

Since the motor 12 continues to rotate thereafter, the sliding contact portion 27c of the drive member 27 climbs up the first slope section B of the cam 26a and reaches the second flat section C. Subsequently, the sliding contact portion 27c becomes the second
Although it slides down the slope section D, since the front end surface of the receiving shaft portion 27a contacts the flange 10i in the middle thereof, the sliding contact portion 27c separates from the cam 26a and faces the first flat section A, but does not contact. Leading to.

Due to this displacement of the drive member 27 in the optical axis direction, the small cylinder 4c of the sub optical system 4 is inserted into the circular hole 10l of the base plate 10, and the holding cylinder 4
The end surface 4b of a comes into contact with the edge of the circular hole 10l to reach the completely retracted position. At this time, the main optical system 3 has reached the retracted position.

The spring 29 supplies the biasing force for inserting the sub optical system 4 into the circular hole 10l after the drive member 27 stops the displacement in the optical axis direction by the front end surface of the bearing portion 27a contacting the collar 10i. .

When the main optical system 3 reaches the retracted position, the switches SW3, SW4, SW5 shown in FIG. 4 are turned off and on, respectively. When the switch SW3 is turned off, the first path is cut off and the power supply to the motor 12 is stopped. Therefore, since the main optical system 3 is stationary at the retracted position and the sub optical system 4 is stationary at the completely retracted position, the optical system is composed of only the main optical system 3 and its focal length is in a wide-angle region. Both switches SW1 and SW5 are ON
Therefore, the automatic focus adjustment / shutter control circuit 31 is in an operable state, and the wide-angle optical system is capable of photographing.

The motor 12 is rotated by receiving power from the third path in response to the image capturing start operation, and displaces the main optical system 3 in the optical axis direction from the close-up of the wide-angle region to the infinity to perform focus adjustment. During the rotation of the motor 12 for adjusting the focus in this wide-angle region, the sliding contact portion 27c of the driving member 27 only faces the first flat section A and does not come into contact therewith, so the driving member 27 does not move, and the sub optical System 4 remains in the fully retracted position.

Then, the finder optical system is switched by the finder optical system switching mechanism in the following manner in response to the change of the above state. That is, the first finder optical system 5 is moved from the insertion position to the retracted position.

Since the base plate 10 is largely retracted because the telephoto state is switched to the wide-angle state, the rack 51 is largely retracted and the rack teeth are moved.
The cam plate 53 is largely rotated by the path of the 51b, the pinion 52a, the transmission shaft 52, the spur gear 52b, and the reduction gear 53a. Transmission shaft 52
Since only the photographing optical system and the viewfinder optical system are connected to each other, the structure of the partition is simple, the light is sufficiently shielded, and the operation resistance is low.

The rotation of the cam plate 53 causes the starting teeth 53b to move to the switching drive member 5
5, the start tooth 55b of the fan-shaped portion 55d is pressed, and the drive tooth 53c and the drive tooth 55c mesh with each other. One tooth is provided between the start tooth 53b and the drive tooth 53c and between the start tooth 55b and the drive tooth 55c. Since it is lacking, the meshing starts smoothly without interference.

Then, as shown in FIG. 11, since the switching drive member 55 is rotated, the tip end portion of the engaging rod 57c is pushed by the first cam surface 55e, and the second objective lens 57 is centered on the swing shaft 57a. Then, when the tip end of the engaging rod 57c reaches the second cam surface 55f, the second objective lens 57 is held at a constant angle when it rotates counterclockwise by a set angle when viewed from above in FIG.

Synchronizing with the angular displacement of the second objective lens 57, the first objective lens 56 draws an arc around the cam portion 55g together with the switching drive member 55, and the end when the second objective lens 57 faces the front is blurred. And moves to the state shown in FIG. 12 and FIG. 14 (B).

Thereafter, the driven pin 59a of the swing lever 59 reaches the area of the drive groove 54b from the first circumferential groove 54a of the cam groove 54. Then, the swing lever 59 rotates clockwise around the pivot 59b as viewed from above in FIG. 3, whereby the split groove 59e, the driven rod 58e,
The rectilinear frame 58 is pushed forward through the linear motion connecting arm 58d.

When the rectilinear frame 58 is pushed forward, the tip end of the engaging rod 57c comes off the second cam surface 55f of the switching drive member 55, so that the second objective lens 57 faces the front as before and interferes with the cam portion 55g. Without moving the linear frame 58 and the second objective lens 57
It is pushed to the original position of the first objective lens 56 instead of the objective lens 56, and the swing lever 59 is inverted and held at the wide-angle position by the toggle spring 59d to the state shown in FIGS. 13 and 14 (C). It becomes a finder optical system for wide angle.

In the wide-angle state, even if the cam plate 53 is rotated for focus adjustment, the vertical movement rod 58e of the rectilinear frame 58 is moved to the inner wall of the split groove 59e of the swing lever 59 and the finder storage portion 1a by the biasing force of the toggle spring 59d. It is held by being held between the front end of the provided guide groove 1f.

The driven pin 59a of the swing lever 59 is connected to the cam groove 5 of the cam plate 53.
The second circumferential groove 54c moves within the range of the second circumferential groove 54c.
Since the driven pin 59a is prevented from coming into contact with the side wall of 54c and the vertical pin 59a moves within the area of the second circumferential groove 54c of the cam groove 54, the rocking lever 59 does not rock. The end of the drive tooth 55c of the fan-shaped portion 55d of the switching drive member 55 has a cam plate.
Since it is in sliding contact with the sliding contact edge 53d of 53, the second objective lens 57
It does not displace and is held stably.

FIG. 7 is a diagram showing the relationship between the amount of extension of the base plate 10 and the switching states of the photographing optical system and the finder optical system. The state X of the photographing optical system and the state Y of the finder optical system are made to correspond to each other. The telephoto state is represented by W and the wide-angle state is represented by T.

As shown in the figure, in the area (a) where the extension amount of the base plate 10 is small, both the photographing optical system and the finder optical system are in a stable wide-angle state, and the base plate 10 is infinite in the area (a). It is possible to move between the far ∞ and the close range N in the wide angle state. When the operation for switching the state is performed, both optical systems are displaced toward the telephoto state via the area (b), and a stable telephoto state is set in the area (c), and infinity ∞ and telephoto are set in the area (c). It is possible to move to and from the closest distance N in the state. The same applies when switching from the telephoto state to the wide-angle state.

(3) When the dust cover is displaced from the open position to the closed position from the telephoto state, switch SW1 turns off and the logic circuit
The input terminal 40a of 40 goes low and the output terminal of the exclusive OR circuit 40e goes high. The following operation is the same as in (2). Even though the focal length selection member 2 is at the telephoto position, the main optical system 3 is displaced from the extended position toward the retracted position, and the sub optical system 4 is at the fully inserted position. To the complete retracted position.

When the main optical system 3 is displaced to the retracted position, the dustproof cover can be displaced to the closed position. When the dust cover reaches the closed position, the switch SW1a in phase with switch SW1
Since it is FF, the power supply to the automatic focus adjustment / shutter control circuit 31 is cut off, and shooting is impossible.

Similarly, in the finder optical system, the telephoto position is switched to the wide-angle position.

(4) When the dust cover is displaced from the wide-angle state to the closed position, the switch SW1a, which is in phase with the switch SW1, is turned off, so the power supply to the automatic focus adjustment / shutter control circuit 31 is cut off and photography is impossible. Become.

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

As a result, the switches SW7a and SW7b shown in FIG. 8 are turned off and the switches SW8a and SW8b are turned on. Since the main optical system 3 is in the retracted position, the switches SW3, SW4, and SW5 are respectively OF
F, ON, ON status. Switches SW8a and SW8b are ON,
Since the switch SW4 is ON, the second path is formed, and the motor 12 starts rotating in the opposite direction to that in the case of (2).
Therefore, the main optical system 3 starts to be displaced from the feeding position toward the feeding position.

By the initial rotation of the motor 12, the sub optical system 4 is displaced in the optical axis direction from the completely retracted position, comes out of the circular hole 10l, and is displaced to the incomplete retracted position (shown in FIG. 8). The displacement in the optical axis direction is caused by the rotation of the cam 26a and the driving member 2 in the second slope section D.
This is because the sliding contact portion 27c of 7 is pushed up. When the sub optical system 4 comes out of the circular hole 10l, the drive member 27 can swing in the direction crossing the optical axis of the main optical system 3.

As the motor 12 continues to rotate, the sliding contact portion 27c is pushed in the direction crossing the optical axis by the second slope section D, so that the driving member is driven.
27 swings in the same direction, and the end surface of the small cylinder 4c of the sub optical system 4 is the base plate.
While sliding on the backside 10m of 10, go from the incomplete retracted position to the incompletely inserted position.

When the main optical system 3 approaches the extended position, the free end of the drive member 27
27d abuts on the locking member 10j and is prevented from swinging, and the sub optical system 4 stops at the incompletely inserted position. After that, the motor 12
Continues rotating, the sliding contact portion 27c of the drive member 27 moves up the second slope section D of the cam 26a and reaches the second flat section C.

Subsequently, the sliding contact portion 27c slides down the first slope surface section B, but the front end surface of the bearing portion 27a abuts the collar 10i in the middle thereof, so the sliding contact portion 27c is separated from the cam 26a, and the first flat section It reaches a state where it faces A but does not contact.

Due to this displacement of the drive member 27 in the optical axis direction, the small cylinder 4c of the holding cylinder 4a of the sub optical system 4 is guided by the guide surface 28 of the positioning means 28.
After abutting against b, it is guided and inserted into the guide surface 28a, and the end surface 4b of the holding cylinder 4a abuts against the abutting surface 28c of the positioning means 28 to reach the complete insertion position shown in FIG. System 4
The positioning is completed. At this time, the main optical system 3 has reached the delivery position.

The bearing member 27a comes into contact with the collar 10i, so that the driving member 27
The spring 29 supplies a biasing force for engaging the sub optical system 4 with the positioning means 28 after the stop of the displacement in the optical axis direction.

When the main optical system 3 reaches the extended position, the switches SW3, SW4, and SW5 are turned on, off, and on, respectively, as described in (1). When the switch SW4 is turned off, the second path is cut off and the power supply to the motor 12 is stopped. Therefore the first
As shown in the figure, the main optical system 3 is at the extended position and the sub optical system 4
Are stationary at the full insertion position, and a synthetic optical system is formed, and the focal length thereof is in the telephoto range. Also switch SW
Since both 1a and Sw5 are ON, the automatic focus adjustment / shutter control circuit 31 is in an operable state, and shooting with the telephoto optical system is possible.

The finder optical system is switched from the wide-angle state to the telephoto state according to the switching operation.

That is, when the main optical system 3 and the sub optical system 4 are switched to the telephoto state, the base plate 10 greatly moves forward, so that the cam plate 53 largely rotates contrary to the above. As a result, the vertical pin 59a of the rocking lever 59 is engaged with the second circumferential groove 54c of the cam groove 54.
From the state to the drive groove 54b, the swing lever 59 rotates counterclockwise from the state shown in FIG. 13 and FIG. 14 (C), and pulls back the second objective lens 57 and the rectilinear frame 58.

When the second objective lens 57 and the rectilinear frame 58 retract, the tip end of the engaging rod 57c abuts on the second cam surface 55f of the cam portion 55g of the switching drive member 55, and the second objective lens 57 is centered on the swing shaft 57a. The state shown in FIG. 12 and FIG. 14 (B), which is held in a state of being tilted at an angle, is obtained.

In synchronization with this, the drive teeth 53c mesh with the drive teeth 55c, the switching drive member 55 is rotated clockwise, and the first objective lens 56
Rotates in an clockwise direction around the swing shaft 55a,
The state shown in FIG. 1 and FIG. 14 (A) is obtained. Next, the tip of the engaging rod 57c reaches the first cam surface 55e of the cam 55g,
Finally, the second objective lens 57 faces the front, and the rectilinear frame 58 returns to the front of the front of the second objective lens 57 and enters the telephoto state shown in FIG.

(6) Switch SW1 turns on when the dust cover is displaced toward the open position from the state where the dust cover is covered in the telephoto state.
And the input terminals 40a and 40b of the logic circuit 40 are both Hig.
It becomes the h level. The following is the same operation as described in (5).

According to the above-described embodiment, since the switching of the photographing optical system, the switching of the finder optical system, and the focus adjustment can be performed by sequentially utilizing the rotation of one motor, a plurality of driving sources can be used. There is an advantage that the camera can be driven and the camera can be downsized.

FIG. 15 shows another embodiment of the present invention. In the embodiment, the second objective lens 57 is moved forward instead of the first objective lens 56, while the first objective lens is simply moved forward. Was designed to escape.

That is, FIG. 15 (A) shows a wide-angle state,
The first objective lens 60 is a concave lens. To set the telephoto state, the second objective lens 57 is moved to the first position as shown in FIG.
The first objective lens 60 is displaced in an arc after being tilted so as to retract from the movement trajectory of the objective lens 60, and after the first objective lens 60 escapes, the second objective lens as shown in FIG. 15 (C). The 57 is returned so that it faces the front.

The interlocking mechanism in the present invention is not limited to the one that is driven by the photographing optical system as in the embodiment, but may be the one that drives the photographing optical system.

[Advantageous Effects] According to the finder optical system magnification switching device of the present invention,
The switching mechanism for the photographic optical system and the viewfinder optical system are linked and linked with only one transmission shaft, so the structure is extremely simple, does not require space, and has no operational resistance, and is compact. The camera can have a long-lasting power supply.

[Brief description of drawings]

1 to 14 show an embodiment of the present invention. FIG. 1 is a vertical sectional view of a camera, FIG. 2 is a horizontal sectional view of a camera, and FIG.
FIG. 4 is a perspective view of the internal mechanism of the camera, FIG. 4 is a perspective view of the photographing optical system switching mechanism, FIG. 5 is a cross-sectional view of essential parts, FIG. 6 is a cam line diagram, and FIG. FIG. 8 is a diagram showing the relationship between the switching states of the photographing optical system and the finder optical system, FIG. 8 is a motor control circuit diagram for driving the optical system, FIG. 9 is a logic circuit diagram for controlling the operation of the motor control circuit, and FIG. Is a plan view of the viewfinder optical system switching mechanism in the telephoto state, FIGS. 11 and 12 are plan views of the same intermediate state, FIG. 13 is a plan view of the same wide-angle state, and FIG. 14 is a viewfinder optical system switching state. FIG. 15 is an explanatory diagram showing a switching state of the finder optical system of another embodiment. 1 ... Camera body, 1a ... Finder housing 3 ... Main optical system, 4 ... Sub optical system 10 ... Base plate, 12 ... Motor 26 ... Cam gear, 27 ... Driving member 51 ... Rack, 53 …… Cam plate 55 …… Switching drive member, 56 …… First objective lens 57 …… Second objective lens

Claims (1)

[Claims] 1. A focal length switchable camera having a photographing optical system capable of moving straight in the optical axis direction for switching focal lengths and adjusting focus at each focal length, and a viewfinder optical system capable of switching magnification. The finder optical system is driven by rotation of a first rotating member that rotates in association with the straight movement of the photographing optical system via a single transmission shaft, and rotation of a second rotating member that is coaxial with the first rotating member. Finder magnification switching device comprising a finder optical system drive mechanism for converting the magnification of.