JPS60258525A - Finder magnification switching device - Google Patents

Abstract

PURPOSE:To prevent oscillation and displacement of a finder optical system by providing a finder optical system driving mechanism between an interlocking mechanism interlocked with displacement of a photographic optical system and the finder optical system and breaking the interlock between the finder optical system and the photographic optical system when the adjusting operation of the photographic optical system is performed for focusing or the like. CONSTITUTION:Two finder optical systems 56 and 57 are provided on a camera body 1 so that their magnifications can be switched, and finder magnifications are switched by a switching driving member 55 when a photographic optical system 3 is displaced for the purpose of switching the focal length. This finder optical system driving mechanism has the first engaging part which can be engaged with the interlocking mechanism interlocked with displacement of the photographic optical system and the second engaging part which can be engaged with a fixed member, and the finder optical system driving mechanism is so constituted that the interlock between the finder optical systems and the photographic optical system is broken when the photographic optical system is displaced for focusing or the like; and thus, the visual field is prevented from being difficult to see by displacement or oscillation of finder optical systems when the adjusting operation of the photographic optical system is performed.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to a photographing optical system that can be displaced in the optical axis direction for switching focal lengths and adjusting focus at each focal length, and a viewfinder that can switch magnification. The present invention relates to a finder magnification switching device for a focal length switching type camera having an optical system.

``Background of the Invention'' Cameras with a so-called optical system switching type have a photographing optical system that can switch the optical effect and can also be moved to adjust the optical effect in each switching state. As cameras have become larger and heavier, it has become a practice to extract the operation of the photographic optical system and switch the finder optical system in conjunction with it.

The photographing optical system performs large switching operations as well as fine movement operations for adjusting focus, etc., whereas the finder optical system only needs to perform switching operations in accordance with the switching operations of the photographing optical system.

If the photographic optical system and finder optical system are always connected, the viewfinder optical system will be displaced or vibrated during the adjustment operation of the photographic optical system, making it difficult to see the field of view or causing energy loss due to unnecessary movement of the finder optical system. The problem was that it was wasted.

``Object of the Invention'' An object of the present invention is to provide a finder magnification switching device that solves the above problems by preventing the finder optical system from vibrating or displacing during photographing.

"Structure of the Invention" In order to achieve the above object, the present invention provides a photographic optical system that can be displaced 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 switching type camera having an optical system, comprising: an interlocking mechanism that interlocks with displacement of the photographing optical system; a finder optical system drive mechanism disposed between the interlocking mechanism and the finder optical system; a fixing member; The finder optical system drive mechanism has a first engaging part that can engage the interlocking mechanism, a second engaging part that can engage the fixed member, and a second engaging part that can engage the fixed member. a biasing member that biases the part in a direction to engage the fixing member, and when the photographing optical system is displaced to switch the focal length, the first engaging part engages the interlocking mechanism. Drives the finder optical system for magnification switching by being engaged with and driven by the biasing member, and maintaining the second engaging portion in a position where it is not engaged with the fixed member against the biasing force of the biasing member; When the photographing optical system is displaced for focus adjustment, the first engagement part disconnects from the interlocking member and moves the second engagement part to the second engagement member.
A finder magnification switching device is characterized in that the engaging part of is brought into engagement with the fixed member according to the biasing force of the biasing member, and when the photographing optical system switches the photographing state, the finder magnification is switched accordingly and the finder magnification is changed accordingly. When the photographing optical system is displaced for photographing after switching the photographing state, the finder optical system is prevented from being adversely affected by the displacement of the photographing optical system.

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

As shown in FIGS. 1 and 2, in a camera equipped with a finder magnification switching device, a focal length selection member 2 is provided on the rear surface of the camera body l, and a dustproof Switch 5 linked to the cover
switch SW2 interlocked with ill and focal length selection member 2
and is provided.

A main optical system 3 is provided on the front side of the camera body 1 so as to be movable in the direction of its optical axis (in the left-right direction in the figure), that is, to be retractable and extendable. Inside the camera body l, a sub optical system 4 is provided in a direction (a direction transverse to the optical axis of the main optical system 3) between a position where it is inserted into the light beam of the main optical system 3, that is, a shooting light beam, and a position where it is withdrawn from the light beam. It is provided so that it can be displaced in the vertical direction (in Fig. 1).

A plurality of finder optical systems including a first finder optical system 5 and a second finder optical system 6 are provided in the upper part of the camera body 1 and housed in a finder housing 1a. As shown in FIG. 14, this finder optical system is a reverse Galilean type consisting of a front group 5a and a rear group 5b.

The switch SWI is set to be OFF when the dustproof cover covers the main optical system 3, and to be ON when the front surface of the main optical system 3 is open. Further, the switch SW2 is set to be turned on when the focal length selection member 2 is at the telephoto position, and turned off when it is at the wide-angle position.

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

This figure shows the state when the main optical system 3 is in the extended position. There is an opening 1 in the center of the plywood lO through which the photographing light flux passes.
0a, and in front of it are fixedly installed an aperture/shutter device 11 and a main optical system 3, which are shown by dashed lines. A motor 12 is fixedly installed on the upper back surface of the base plate 10. Both ends of the rotating shaft protrude through both end faces of the casing of the motor 12. A bevel gear 12a (shown in FIG. 4) is fixed to one end of the rotating shaft. A bevel gear 13, which is pivotally supported by the plywood 10, meshes with this bevel gear 12a, and a gear 14, which is also pivotally supported by a base plate, meshes with the spur teeth of this gear 13.

A through hole is formed in the center of the gear 14, and a female thread is cut in the through hole with the rotation center of the gear 14 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 its end is fixed to the substrate 1c of the camera body 1, and its tip is connected to the through hole 1 of the plywood lO.
0b so as to be slidable in the axial direction.

A bevel gear 12b is fixed to the other end of the rotating shaft of the motor 12.

This bevel gear 12b is engaged with a bevel gear 16 which is discontinued on the base plate 10, and the input gear 17a of the gear train 17 which is discontinued on the base plate 10 is engaged with the spur tooth portion of this gear 16.

Output gear 1 of gear train 17? A through hole is formed in the center of b, and a female thread is cut in this through hole with the rotation center of the gear 17b as the axis. A male thread cut on the guide shaft 18 is screwed into this female thread. One day on the guide axis is
It extends in the optical axis direction, and its end is fixed to the substrate 1c of the camera body, and its tip is inserted into the through hole 10c of the plywood 10 so as to be slidable in the axial direction.

The amount and direction of rotation of the gear 14, 17b with respect to a certain amount of rotation of the motor are set to be equal, and the conditions for the screwing of the gear 14 and the guide shaft 15 and the screwing of 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 implanted in the substrate 1c. Guide shaft 19
is inserted into a through hole 10e of an overhanging portion 10d protruding from the back surface of the base plate 10 and a through hole 10f of the plywood lO so as to be slidable in the axial direction.

With this configuration, when the motor 12 rotates, the gear 14 and the guide shaft 15 are screwed together, and the gear 17b and the guide shaft 18 are screwed together, so that the one plate 10 remains perpendicular to the optical axis and rotates toward the optical axis. a main optical system 3 that is moved parallel to the direction and fixed thereto;
The aperture/shutter device M11 is displaced in the optical axis direction between an extended position and a retracted position.

A printed circuit board 20 is fixed on the right side of the plywood IO. A conductive land 20 is provided on the surface of this printed circuit board 20.
a to 20c are provided, and three sliding contact pieces 21 to 23 fixed to the camera body are slidable on these, respectively. The sliding contact piece 21 and the conductor land 20a connect the switch 5113, and the sliding contact piece 22 and the conductor land 20b
and the switch SW4, the sliding contact piece 23 and the conductor land 20.
and c constitute a switch SW5.

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.

The switches 5llI3 and SW4 function as limit switches, and cut off the power supply to the motor 12 when the main optical system 3 is displaced to the retracted position or the extended position.

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 of the above-mentioned reposition and cannot form a subject image 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. 8).

It should be noted that the film 24 is attached to the photographing aperture 1d made in the substrate 1c.
located behind the

FIG. 4 is a perspective view of a sub-optical system mounting/detaching mechanism disposed on the back surface of the plywood lO.

In the figure, a reduction gear train 25, a cam gear 26, and a drive member 27 are pivotally supported on the back surface of the base plate 10.

The driving member 27 holds the sub optical system 4 . The input gear 25a of the reduction gear train 25 meshes with the spur tooth portion of the bevel gear 13, and the final gear 2 of the reduction gear train 25
5b meshes with the cam gear 26.

The cam gear 26 and the drive member 27 are coaxial, and are coupled via a front cam 2Ba 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 (shown by a solid line) inserted into the photographing light beam, and when the main optical system 3 is in the extended position, the sub optical system 4 is placed in the inserted position (shown by a solid line). 4 is placed at a retracted position (indicated by a two-dot chain line) where it is retracted from the photographing light beam.

FIG. 5 shows a sectional view of the sub-optical system mounting/detaching mechanism.

In the figure, a main optical system 3 and an aperture/shutter device 11 are fixedly installed on a plywood board 1o in front of an aperture 10a.
A positioning means 28 for the sub optical system 4 is formed behind a. The positioning means 28 includes an inner cylindrical surface 28a having the optical axis of the main optical system 3 as its axis, a dome-shaped guide surface 28b, and an abutment surface 28c perpendicular to the optical axis of the main optical system 3.

This positioning means 28 can hold a holding cylinder 4a that integrally holds the sub optical system 4, and when the holding tube 4a is held, the optical axis of the sub optical system 4 is aligned with the light 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 achieved 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 positioning in the optical axis direction is performed by holding the holding cylinder 4a.
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. A circumferential groove 27b is formed in the drive member 27 to accommodate the sub optical system 4 in a loosely fitted state.

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 a front cam 28a formed on this end surface.

The shaft 10g has a flange 10h and I so as to sandwich the bearing part 27a.
A spring 30 is inserted between the collar 10h and the drive member 27. The spring 3o functions to press the sliding portion 27c of the drive member 27 against the cam 28a or to press the front end surface of the bearing portion 27a 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 1 [HL is provided into which the small cylinder 4c of the sub-optical system 4 brought to the retracted position falls into in a loosely fitted state.

FIG. 5 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.

In other words, there is an incomplete insertion position where the small cylinder 4c is in the insertion position but is pushed back by the front cam 28a and does not engage with the positioning means 28, and the small cylinder 4c is in the circular hole 11 but the small cylinder 4c is pushed down by the front cam 28a. This is an incompletely retracted position in which the small cylinder 4c has not been pushed up and fallen into the 10th round hole, and a completely retracted position in which the small cylinder 4c has fallen into the 10th round hole.

FIG. 6 shows a cam diagram of the cam 26a.

The cam 28a has a lifting height of O as the rotation angle e changes from O to el.
A first flat section A where the lift does not change at , a first slope section B where the lifting head increases linearly from O to hl from el to e2, and a second flat section C where the lifting head does not change at hl from e2 to e3. , e3, and a second slope section in which the lift linearly decreases from hl to 0 from 380'.

The cam 2Ela 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 incompletely inserted position and the incompletely retracted position in a direction that crosses one 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.

FIG. 3 shows the interlocking mechanism and finder magnification switching device. The first finder optical system 5 is in 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 guided by a guide shaft 51a whose base end is implanted in the substrate IC and whose front part is loosely fitted into the plywood lO. has been done.

A pinion 52a fixed to the lower end of the transmission member 52 is engaged with rack teeth 51b carved on the rack 51, and a spur gear 52b at the upper end of the transmission member 52 is engaged with the cam plate 5.
It is meshed with a reduction gear 53a fixedly attached to 3.

A cam groove 54 is carved on the top surface of the cam plate 53.
A driving tooth 53b and a sliding contact edge 53d of the driving tooth 53C1 are formed on the periphery, and the driving tooth 53C1 is continuous with one tooth missing from the starting tooth 53b.

A switching drive member 55 is provided adjacent to the cam plate 53 and is pivotally supported by the finder storage portion 1a via a swing shaft 55a. The switching drive member 55 includes activation teeth 55b corresponding to the activation teeth 53b and drive teeth 53c of the cam plate 53,
A cam portion 55 consisting of a fan-shaped portion 55d having drive teeth 55c, a first cam surface 55e in a substantially radial direction formed around the swing shaft 55a, and a second cam surface 55f that is a circumferential surface.
g, and a swing arm 55h extending radially from the swing shaft 55a.

A first objective lens 56 is fixed to the tip of a support arm 55i extending upward from the tip of the swing arm 55h, and this first objective lens 5B forms a first finder optical system.

The switching drive member 55 is biased clockwise when viewed from above in FIG. 3 by a spring 55j stretched between it and a pin protruding from the finder housing 1a.

As can be seen in FIG. 10, when the finder optical system is in a telephoto state and the first objective lens 56 is an element thereof, the spring 55j moves the first objective lens 56 or a member interlocking therewith into the finder housing la. - It is held against the Y end 1g.

In this state, the activation teeth 55b of the switching drive member 55, which is a vertically moving member, are separated from the cam plate 53, and the interlocking movement between the cam plate 53 and the switching drive member 55 is cut off.

In the above mechanism, the starting tooth 55b and the driving tooth 55c of the switching drive member 55 form the first engaging part, and the end surface of the first objective lens 56 that comes into contact with the stopper end 1g forms the second engaging part. .

A second objective lens 57 constituting a second finder optical system is swingably supported on a rectilinear frame 58 via a swing shaft 57a.
The rectilinear frame 58 is supported within the finder housing la so as to be movable rectilinearly in the optical axis direction of the finder optical path.

The locking pin 5 that projects downward from the second objective lens 57?
A spring 58b is stretched between the locking pin 58a projecting downward from the rectilinear frame 58, and the second objective lens 57 is biased clockwise when viewed from above in FIG. 5? b
is held in contact with the lower side 58c of the rectilinear frame 58 and facing forward.

Further, a retaining rod 57C protrudingly provided on the lower end surface of the second objective lens 57 extends downward, and its tip is connected to the switching drive member 57C.
It engages with the cam portion 55g of No. 5. The rack 51. Transmission member 52. Cam plate 53. Switching drive member 55. The engagement rod 57c and the like constitute a second finder optical system driving means.

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

A driven pin 59 a protruding from the swing lever 58 is engaged with the cam groove 54 of the cam plate 53 . Swing - The base end of the lever 58 is pivotally supported by the finder storage part 1a via a pivot 59b, and a pin 58c protrudes from the end further from the pivot 59b and a pin fixed to the finder storage part 1a! A toggle spring 59d that holds the swing lever 58 in the telephoto position and the wide-angle position is stretched between the lens and the lens.

The cam groove 54 of the cam plate 53 includes a first circumferential groove 54a that does not operate the driven pin 59a, a driving groove 54b that moves the driven pin 59a and swings the swing lever 58, and a first circumferential groove 54b that does not move the driven pin 58a. 2 circumferential grooves 54c.

A substantially U-shaped groove 59e is formed at the tip of the swing lever 59, and a vertical groove 59e extending downward from a linear motion connecting arm 58d that projects rearward from the linear frame 58 is formed in the split groove 59e. The tip of the moving rod 58e is engaged.

The tip of the vertically moving rod 58e is further slidably engaged with a guide groove 1f bored in the finder housing 1a.

As can be seen in FIG. 10 or 13, the toggle spring 58d reverses its biasing direction and presses the vertical rod 58e against the rear end or front end of the guide groove 1f bored in the finder housing 1a. The swing lever 58 is held.

At this time, the driven pin 59a is held at an intermediate position where it does not touch the side walls of the first circumferential groove 54a or the second circumferential groove 54c, and the interlocking movement between the swing lever 58 and the switching drive member 55 is cut off. . In the above mechanism, the driven pin 59a serves as the first engaging portion, and the vertical rod 58e serves as the second engaging portion.

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 a path from the positive electrode of the power source E to the switch SW3 to the switch 5W motor 12 to the switch 5I117b 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 SW4 to the switch 5W8a to the motor 12 to the switch SW8b 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, SW8
b is a semiconductor switch whose opening/closing is controlled by a logic circuit 40 (shown in FIG. 9), which will be described later.

The third path is the automatic focus adjustment/shutter control circuit 31
and the motor 12, and this control circuit 31
The output of the motor 12 causes the motor 12 to rotate forward and reverse, moving the optical system back and forth in the optical axis direction and bringing the optical system into focus.

In the power supply path of this control circuit 31, switches 5W1a and SW5 connected in series are inserted. switch 5W
Reference numeral 1a denotes a semiconductor switch that is controlled by the switch 5lll and opened and closed in the same phase as this, and is turned on only when a dustproof cover (not shown) is in the open position. The switch 5115 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 the fully retracted position). These prevent automatic focus adjustment and shutter operation when the dustproof cover and optical systems 3 and 4 are in positions inappropriate for photographing.

FIG. 9 shows a logic circuit 40 that controls the operation of the motor control circuit of FIG. This logic circuit 40 includes a pair of input terminals 40a, 40b and a pair of output terminals 40c, 40.
d. The input terminal 40a is connected to the above switch SW.
The input terminal 40b is connected to the switch S between I and the grounding resistor.
Between W2 and the ground resistor, the output terminal 40c is connected to the control terminals of the switches 5W7a and 5W7b, and the output terminal 40d is connected to the control terminals of the switches 5W8a and 8b.

The input terminal 40a is at the old GH level when the switch SWI is ON, that is, when the dustproof cover is in the open position.
When the switch SW1 is OFF, that is, when the dustproof cover is in the closed position, it becomes Low level. The input terminal 40b is at the old gh level when the switch SW2 is ON, that is, when the focal length selection member 2 is at the telephoto position, and when the switch SW2 is OFF, that is, the focal length selection member 2 is at the telephoto position.
becomes Low level when is at the wide-angle position.

When the output terminal 40c is at High level, the above switch 5
Both W7a and 5W7b are turned on, and both are turned off when they are at low level. When the output terminal 40d is at High level, both the switches 5W8a and 5W8b are turned on, and the output terminal 40d is set to L.
oll Turn OFF at both L/bevel.

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

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

The table below shows the position of the dustproof cover, the position of the focal length selection member 2, and the switch SWI that changes depending on these positions.
, the state of SW2, the input terminals 40a, 4 of the logic circuit 40
0b, output terminal 40c, 40d level, switch 5W
The relationship between the states of 7a, 5W7b, 5W8a, and 5W8b, 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 SWI and 5i12 are ON. Therefore, the input terminal 40 of the logic circuit 40
a and 40b are both at High level. The output terminals of exclusive OR circuit 40e and NOR circuit 40f are Lo
When the W level reaches the level, 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 5W7 shown in FIG.
b is OFF, switches 5W8a and 5W8b are ON
becomes. Since the main optical system 3 is in the extended position, the switches SW3, SW4, and SW5 are turned ON and OFF, respectively, as shown in FIG.

It is in the ON state. Switch SW? a, 5W7b is OF
F, the first path is not formed and the switch S
Since W4 is OFF, the above-mentioned 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 each stand still at the fully inserted position where they are fully engaged with the positioning means 28, and both optical systems constitute a composite optical system, whose focal length is in the telephoto range.

Since the switches 5W1a and SW5 are both ON, the automatic focus adjustment/shutter control circuit 31 is in an operable state, and photography with the telephoto optical system is possible. FIG. 1 shows the state at this time.

In response to the shooting start operation, the motor 12 receives power through the third path and rotates, displacing the optical systems 3 and 4 in the optical axis direction between close range and infinity in the telephoto range, thereby adjusting the focus. During the rotation of the motor 12 for focus adjustment in this telephoto range, the front end surface of the bearing portion 27a of the drive member 27 is rotated by the spring 30.
Since the sliding portion 27c of the driving member 27 is in contact with the collar 10i due to the urging force of the cam 28a, the sliding portion 27c of the driving member 27 only faces the first flat section A of the cam 28a and does not come into contact with it. Therefore, the sliding contact portion 27c
does not become a load on the motor 12.

Further, in the finder optical system, the first objective lens 5B is located in front of the second objective lens 57, and as shown in FIGS.
The camera is in a telephoto state as shown in Figure 4 (A).

Main optical system for focus adjustment for telephoto shooting 3. The base plate lO of both the sub optical system 4 is displaced back and forth, thereby causing the cam plate 5 to move forward and backward.
3 rotates, the vertical rod 58e of the rectilinear frame 58 is held between one inner wall of the split groove 59e of the swing lever 58 and the rear end of the guide groove 1f provided in the finder housing 1a, The activation teeth 53b of the cam plate 53 are held by the biasing force of the toggle spring 59d, ! : Separated from the activation tooth 55b of the switching drive member 55, and the vertical pin 5 of the swing lever 59
9a is the first circumferential groove 54 of the cam groove 54 of the cam plate 53;
Since the vertical movement pin 59a moves within the range of a and does not come into contact with the side wall of the first circumferential groove 54a, the finder optical system will not be switched or vibrated due to operation.

(2) When the focal length selection member 2 is switched to the wide-angle position from the state shown in figure fffJ1, the switch SW2 is turned OFF.
state, and 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 old gb level, the output terminal of the OR circuit 40g is inverted to the old gh level, and the output terminals 40c and 40d of the logic circuit 40 are inverted to High and Low levels, respectively.

As a result, the switches 5W7a and 5W7b shown in FIG. 8 are turned on, and the switches 5W8a and 5W8b are turned off. Since the main optical system 3 is in the extended position, as shown in FIG. 3, near, y + SW3. SW4. SW5 is ON and OFF respectively.

It is in the ON state, and switches 5W7a and 5W7b are ON.
Therefore, 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. 5) where it engages with the positioning means 28 during the initial rotation of the motor 12, to the incomplete insertion position where it does not engage with the positioning means 28. Displace. This displacement in the optical axis direction is caused by the movement of the cam 2Ba into the third position.
The sliding contact portion 27c of the drive member 27 is pushed up in the first slope section B by rotating clockwise from the state shown in the figure.

When the sub optical system 4 reaches the incomplete insertion position, the positioning means 28
When the drive member 27 is released from the engagement with the optical axis, the drive member 27 becomes swingable in a direction transverse to the optical axis, so as the motor 12 continues to rotate, the sliding portion 27c is pushed by the first slope section B and the main optical system It swings clockwise in a plane that crosses the optical axis of No. 3.

At this time, the end surface of the small cylinder 4C of the sub optical system 4 slides on the back surface lh of the plywood lO, which is perpendicular to the optical axis of the main optical system 3, and swings in the same direction. 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 is prevented from swinging, and the sub optical system 4 is placed at an incomplete insertion position where it is not inserted into the circular hole 10M. reach.

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. Subsequently, sliding contact part 2
7c slides down the second slope section, but on the way, the front end surface of the receiving shaft section 27a contacts the flange 10i, so the sliding contact section 27c separates from the cam 2fla and faces the first flat section A. However, it reaches a state where there is no contact.

Due to the light and axial displacement of the drive member 27 accompanying this, the small cylinder 4C of the sub optical system 4 is inserted into the circular hole 10 of the base plate 10, and the end surface 4b of the holding cylinder 4a is attached to the edge of the circular hole 10. comes into contact with and reaches the fully retracted position. At this time, the main optical system 3 has reached the retraction position.

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,
The biasing force for inserting the sub optical system 4 into the circular hole 10M is provided by the spring 2.
3 supplies.

When the main optical system 3 reaches the retraction position, the switches SW3, SW4, and SW5 shown in FIG. 4 are turned OFF.
,ON.

becomes the state of 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 is stationary at the retracted position, and the sub optical system 4 is stationary at the completely retracted position, so the optical system is stationary at the main optical system 3.
The focal length is in the wide-angle range. Further, since the switches SWI and SW5 are both ON, the automatic focus adjustment/shutter control circuit 31 is in an operable state, and photographing with the wide-angle optical system is possible.

In response to the photographing start operation, the motor 12 receives power through the third path and rotates, displacing the main optical system 3 in the optical axis direction between close range and infinity in the wide-angle area, thereby adjusting the focus. During the rotation of the motor 12 for focus adjustment in this wide-angle region, 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.

Then, in response to the change in the above state, the finder optical system is switched as follows by the finder magnification switching device. That is, the first finder optical system 5 is moved from the insertion position to the retracted position.

Because the telephoto state is switched to the wide-angle state, the base plate 10 moves back a lot, so the rack 51 moves back a lot, and the cam plate 53 is rotated a lot by the path of the rack teeth 51b, pinion 52a, spur gear 52b, and reduction gear 53a. Ru. As a result, the activation tooth 53b pushes the activation tooth 55b of the fan-shaped portion 55d of the switching drive member 55, and the driving tooth 53c and the driving tooth 55c engage with each other.
Since one tooth is missing between the starting tooth 55b and the driving tooth 55c and between the starting tooth 55b and the driving tooth 55c, meshing starts smoothly without interference.

Then, as shown in FIG. 11, 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. Then rotate the locking rod 5? counterclockwise by the set angle when viewed from above in Figure 3. The tip of c is the second cam surface 55f
, the second objective lens 57 is held at a constant angle.

Pi', in synchronization with the angular displacement of the second objective lens 57, the first
The objective lens 56 is connected to the cam portion 55 together with the switching drive member 55.
12 and 14.
The state shown in Figure (B) is reached.

After that, the driven pin 59a of 8-58 swings and reaches the region of the drive groove 54b from the first circumferential groove 54a of the cam groove 54.

Then, the swing lever 58 moves to the third position around the pivot shaft 59b.
When viewed from one side, the split groove 58e, the driven rod 58e, and the direct-acting connecting arm 58d rotate clockwise.
The rectilinear frame 58 is pushed forward via the .

When the rectilinear frame 58 is pushed forward, the tip of the retaining rod 57c comes off the second cam surface 55f of the switching drive member 55, so the second objective lens 57 faces the front like a binary lens and faces the cam part 55g. Without interference, the rectilinear frame 58 and the second objective lens 57 are pushed out to the original position of the first objective lens 5B, replacing the first objective lens 56, and swing/<-
59 is inverted and held in the wide-angle position by a toggle spring 59d, and becomes the state shown in FIGS. 13 and 14(C), thus becoming a wide-angle finder optical system.

In the wide-angle state, even when the cam plate 53 is rotated for focus adjustment, it swings due to the biasing force of the vertical rod 58e4 of the rectilinear frame 58 and the toggle spring 59d, and the inner wall of the groove 59e of <-59 and the finder It is held between the front end of the guide groove 1f provided in the storage section 1d.

The driven pin 59a of the swing lever 58 moves within the range of the second circumferential groove 54c of the force L4 groove 54 of the cam plate 53, and the driven pin 59a does not come into contact with the side wall of the second circumferential groove 54c. Since the vertical pin 58a moves within the area of the second circumferential groove 54c of the cam groove 54, it swings/<-
59 does not swing, and the end of the drive portion 55c of the fan-shaped portion 55d of the switching drive member 55 is in sliding contact with the sliding edge 53d of the cam plate 53, so the second objective lens 57 is not displaced. , is held stable.

FIG. 7 is a diagram showing the relationship between the amount of extension of the base plate 10 and the switching state of the photographing optical system and the finder optical system,
The state X of the photographing optical system and the state 7g7 of the finder optical system are made to correspond, with W representing the telephoto state and T representing the wide angle state.

As shown in the figure, in the region (a) where the plywood 10 is only slightly extended, both the photographing optical system and the finder optical system are in a stable wide-angle state, and the base plate 10 is at infinity in the region (a). It is possible to move between (1) and the close distance N in the wide-angle state. When an operation is performed to switch the state, both optical systems are shifted to the telephoto state via region (b), and the direction of both optical systems is shifted to the telephoto state through region (c).
Then, it becomes a stable telephoto state, and it reaches infinity in area (c).
It is possible to move between the distance N in the telephoto state and the close distance N in the telephoto state. The same applies when switching from a telephoto state to a wide-angle state.

(3) When the dustproof cover is moved from the open position to the closed position from the telephoto state, the switch SWI turns OFF and -
The input terminal 40a of the logic circuit 40 becomes Low level,
The output terminal of the exclusive OR circuit 40e has the old name h level. The following operation is similar to (2), and even though the focal length selection member 2 is at 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 moved to the fully inserted position. It is displaced from the position toward the fully retracted position.

When the main optical system 3 is moved to the retracted position, the dustproof cover can be moved to the closed position. When the dustproof cover reaches the closed position, the switch 5W1a, which is in phase with the switch 51111, is turned OFF, so power supply to the automatic focus adjustment/shutter control circuit 31 is cut off, and photographing is no longer possible.

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

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

Since it is turned off, the power supply to the automatic focus adjustment/shutter control circuit 31 is cut off, and photographing becomes impossible.

(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 input terminals 40a and 40b of the logic circuit 40 are both at the old gh level. Exclusive OR circuit 40e, Noah circuit 4
Since the output terminals 0f are both at a low level, the output terminal of the OR circuit 40g is inverted to a low level, and the output terminals 40c and 40d of the logic circuit 40 are each low.

Inverted to High level.

As a result, switches 5W7a and 5W7b shown in FIG.
is OFF, and switches 5W8a and 5Web are ON.
Since the main optical system 3 is in the retracted position, the switch S
W3.

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

Switches 5W8a and 5W8b are ON, and switch 5
Since 114 is ON, the second path is formed,
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 is displaced from the completely retracted position in the optical axis direction, exits the circular hole 10, and is displaced to the incompletely retracted position (shown in FIG. 8). This displacement in the forward axial direction is caused by the rotation of the cam 2Ela and pushing up the sliding contact portion 27c of the drive member 27 at the second slope section. When the sub optical system 4 comes out of the circular hole 10JJ, 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 the 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 face slides on the back surface 10+w of the base plate lO, moving from the incompletely retracted position to the incompletely inserted position.

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. Since the motor 12 continues to rotate thereafter, the sliding portion 27c of the drive member 27 ascends the second slope section of the cam 28a, and
The second flat section C is reached.

Subsequently, the sliding contact portion 27c slides down the first slope section B, but on the way, the sliding portion 27c slides down the bearing portion 2? Since the front end surface of a comes into contact with the flange 10i, the sliding portion 27c separates from the cam 2Ba and reaches a state where it faces the first flat section A but does not come into contact with it.

Due to the accompanying 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 comes into contact with the guide surface 28b of the positioning means 28, and is guided by this and moves to the guide surface 28.
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. 5 is reached. At this time, the main optical system 3 has reached the feeding position.

Note that the biasing force that causes the sub optical system 4 to engage with the positioning means 28 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 is as follows.

Spring 29 supplies it.

When the main optical system 3 reaches the extended position, the switch SW3. SW4. SW5 is O
N, OFF, 0N (7) state E Ninal. When the switch 8w4 is turned off, the second path is cut off and goes to the motor 12.

The power supply will be stopped. Therefore, as shown in FIG. 1, 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. In addition, since the switches 5W1a and 8w5 are both ON, the automatic focus adjustment/shutter control circuit 3
1 is in an operable state and is capable of photographing with a telephoto optical system.

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 plywood 10 moves forward a lot, so the cam plate 53 rotates a lot, contrary to the above. As a result, the vertical movement pin 59a of the swing lever 59 reaches the drive groove 54b from the second circumferential groove 54c of the cam groove 54, and the swing lever 59 moves counterclockwise from the state shown in FIGS. 13 and 14 (G). The second objective lens 57 and the rectilinear frame 58
pull back.

When the second objective lens 57 and the rectilinear frame 58 retreat, the tip of the retaining rod 57c is switched to the cam portion 5 of the switching drive member 55.
5g of the second cam surface 55f, and the second objective lens 57
is in the state shown in FIG. 12 and FIG. 14(B) in which it is held in an angularly tilted state about the swing axis 57a.

In synchronization with this, the drive tooth 53c meshes with the drive tooth 55c, and the switching drive vJ-tfB member 55 is rotated clockwise.
The first objective lens 5B rotates clockwise in an arc around the swing axis 55a, and enters the state shown in FIG. 11 and FIG. 14(A). Next, the tip of the engagement rod 57c reaches the first cam surface 55e of the cam portion 55g, and finally the second objective lens 57 faces the front, and the rectilinear frame 58 reaches the second objective lens 55.
7 and returns to the front of the camera, and enters the telephoto state shown in FIG.

(6) When the dustproof cover is moved from the state where the dustproof cover is covered to the open position in the telephoto state, the switch SWI is turned on, and the input terminals 40a and 4 of the logic circuit 4o are turned on.
Both 0b are at the old gh level. The following operation is the same as that described in (5).

According to the second embodiment, the switching of the photographing optical system, the switching of the finder optical system, and the focus adjustment can be performed by sequentially using the rotation of one motor. This has the advantage that multiple drives can be performed and the camera can be made smaller.

FIG. 15 shows another embodiment of the present invention. In the previous embodiment, the second objective lens 57 was moved forward in place of the first objective lens 56, whereas the first objective lens 57 was
This allows the objective lens to escape.

That is, FIG. 15(A) shows a wide-angle state, and the first objective lens 60 is a concave lens. To achieve a telephoto state, as shown in FIG. 15(B), the second objective lens 5 is
7 is tilted to retreat from the movement trajectory of the first objective lens 60, and then the first objective lens 60 is displaced in an arc, and after the first objective lens 60 escapes, as shown in FIG. 15(C). This is to return the second objective lens 57 to face one surface.

Note that the interlocking mechanism in the present invention is not limited to one that follows the photographic optical system as in the embodiments, but may be one that follows the photographic optical system.

"Effects of the Invention" According to the finder magnification switching device according to the present invention, when the operation of the photographic optical system is extracted and the finder optical system is switched in conjunction with the operation, adjustment of the optical function of the photographic optical system such as focusing is performed. During operation, the link between the finder optical system and the photographing optical system is disconnected, so the viewfinder optical system does not displace or vibrate or the field of view becomes distorted when adjusting the photographic optical system. It's easy to take pictures, and it also doesn't waste energy due to unnecessary movement of the finder optical system. This makes it an extremely excellent finder magnification switching device.

[Brief explanation of drawings]

1 to 14 show an embodiment of the present invention, in which FIG. 1 is a vertical sectional view of the camera, FIG. 2 is a horizontal sectional view of the camera, FIG. 3 is a perspective view of the internal mechanism of the camera, and FIG. Figure 4 is a perspective view of the photographing optical system switching mechanism, Figure 5 is a sectional view of the main part, Figure 6 is a cam diagram, and Figure 7 is a diagram showing the amount of plywood extension and the switching state of the photographing optical system and finder optical system. Diagrams showing the relationship; 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; FIG. 11 and 12 are plan views in an intermediate state, FIG. 13 is a plan view in a wide-angle state, FIG. 14 is an explanatory diagram showing the switching state of the finder optical system, and FIG. 15 is a plan view of another embodiment. It is an explanatory view showing a switching state of a finder optical system. 1... Camera body 1a... Finder storage section 3.
...Main optical system 4...Sub-optical system 10...Bed plate 12...Motor 26...Cam gear 27...Drive member 5I...Rack 53...Cam plate 55...FjJ Replacement drive drive member 5B...First objective lens 57...Second objective lens Fig. 5 Fig. 6 Fig. 02] Mine flue θ □ Fig. 7 (0014N) Cbekov (N
) Fig. 72 Fig. 73 Fig. 141 Nu 1 No./,, 5 Kyou (A) (A)

Claims (1)

[Claims] (1) In a focal length switching camera having a photographing optical system that can be displaced in the optical axis direction for switching the focal length and adjusting the focus at each focal length, and a finder optical system that can switch the magnification, an interlocking mechanism interlocking with the displacement of the optical system, a finder optical system drive mechanism disposed between the interlocking mechanism and the finder optical system, and a fixing member, the finder optical system drive mechanism a first engaging part capable of engaging with the mechanism; a second engaging part capable of engaging the fixing member; and urging the second engaging part in a direction to engage the fixing member. and a biasing member. When the photographing optical system is displaced to switch the focal length, the first engaging part engages and follows the interlocking mechanism to drive the finder optical system to switch the magnification, and the second engaging part The first engaging portion is maintained in a position where it does not engage with the fixed member against the biasing force of the biasing member, and when the photographing optical system is displaced for focus adjustment, the first engaging portion The connection with the interlocking member is cut off, and the second
A finder magnification switching device characterized in that the engaging portion is brought into engagement with the fixed member according to the biasing force of the biasing member.