JPH04294336A - Camera - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera, and more particularly, it has an optical system structure configured to guide a light beam passing through a photographing optical system to a finder optical system, and
The present invention relates to a camera equipped with a lens shutter.

0002

2. Description of the Related Art Current still cameras compatible with silver halide film can be roughly divided into cameras with interchangeable lenses and cameras with non-interchangeable lenses.

A typical example of the former is a single-lens reflex camera that has a so-called TTL optical system configured to obtain a light flux to a finder optical system and a light flux for photometry through a photographing optical system, and a typical example of the latter is a single-lens reflex camera that has a so-called TTL optical system. This is a so-called compact camera in which the finder optical system and photographic optical system are completely separated.

[0004] Ever since the introduction of single-lens reflex cameras, compact cameras have been designed to be inexpensive, small, lightweight, and easy to handle even for amateurs. While a lens shutter that could be used for multiple purposes was adopted, and electronic control of various operations was promoted to simplify operations, there were no plans to upgrade the basic functions of the camera.

[0005] Recently, however, with the increasing demand for compact cameras, development aimed at increasing the functionality of compact cameras has begun, and as a result, today, among the compact cameras on the market, Many models have become so-called zoom cameras with zoom lenses.

As described above, it is expected that the development trend of providing non-interchangeable lens cameras with functions similar to those of single-lens reflex cameras will continue. In order to have the same functionality as a reflex camera, it is necessary to change the basic design of conventional compact cameras. For example, in conventional compact cameras, the shooting optical system was a non-zoom lens with constant magnification, so the parallax between the shooting optical system and the finder optical system was negligible.However, as the shooting magnification increases, parallax also increases. Therefore, if a zoom lens is used as the photographing optical system in a conventional compact camera, the parallax value becomes large enough to not be ignored, and from this point on, it is no longer possible to follow the structure of the conventional optical system. In addition, cameras with zoom lenses need to be able to accurately measure the distance to distant objects, but it is difficult to measure distances with the active distance measuring devices used in current compact cameras, so they are passive. It will be necessary to change to a conventional distance measuring device. Therefore, it can be said that it is desirable to adopt the same TTL system as the current single-lens reflex camera for the structure of the optical system of the camera.

However, recently, single-lens reflex cameras have been developed that are lighter and cheaper than conventional products, so the traditional characteristics of non-interchangeable lens cameras, such as light weight, small size, and low price, have also been taken into account. If development is not done, non-interchangeable lens cameras will lose their significance compared to single-lens reflex cameras. Therefore, it is necessary to design a device that is lightweight, compact, and inexpensive.

From this point of view, even if newly developed non-interchangeable lens cameras adopt the same TTL optical system structure as single-lens reflex cameras, for example, the shutter may have a focal plane shutter rather than a focal plane shutter. It is also desirable to adopt a lens shutter suitable for downsizing the entire camera.

[0009]

[Problems to be Solved by the Invention] As mentioned above, when assuming a camera equipped with a TTL optical system structure and a lens shutter, the lens shutter is a half-open type shutter, so it is not included in the TTL optical system structure. It is important to control the related operations of the movable mirror and lens shutter. That is, in this type of camera, in order to introduce subject light into the finder optical system, it is necessary to open the shutter when the mirror is in the down state, and it is necessary to ensure reliable interlocking between the shutter and the mirror. A control system must be provided to allow this to occur. if,
If the two were not linked accurately, there was a risk that exposure would be performed against the photographer's wishes.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a camera that has a TTL optical system and a lens shutter, and has interlock control means for interlocking the mirror of the optical system and the shutter. It is.

[0011]

[Means for Solving the Problems] The camera of the present invention disclosed in the following embodiments includes a mirror position detection means for detecting the position of the mirror, and a shutter state detection means for detecting the state of the shutter. At least one of the detection means is provided, and the shutter or the mirror is controlled based on the output of the detection means.

0012

[Operation] As shown in FIG. 2, the camera of the first embodiment according to the present invention is provided with mirror position detection switches 26 and 29 for detecting the position of the mirror 20.
When the switch detects that the mirror 20 is in the first position as shown in the figure, a control means such as a microcomputer shown in FIG. 5 controls the shutter drive circuit 46 to allow the lens shutter 24 to open. When the lens is not in the mirror down position, the lens shutter 24 is not allowed to open.

[0013] Furthermore, in the camera of the second embodiment of the present invention,
As shown in FIG. 9, a shutter state detection switch 64 is provided in the shutter mechanism, and when the switch detects that the lens shutter 24 is fully closed, the mirror 20 is allowed to be moved to the mirror-up position. is configured to do so.

[0014]

Embodiments Below, embodiments of the present invention will be described with reference to the drawings. 1 to 6 are diagrams showing the structure and function of a camera according to a first embodiment of the present invention. In FIGS. 1 to 6,
1 is the camera body, 2 is the photographic film, 3 is the first lens group of the photographic optical system, 4 is the second lens group, 5 is the third lens group,
6 is the fourth lens group.

Reference numeral 7 denotes a fixed cylinder fixed to the main body 1, which includes a straight groove 7a (see FIG. 4) that restricts the rotation of a zoom cam ring 14 and a second group cylinder 16, which will be described later, and a parallel groove that releases the rotation restriction of the zoom cam ring 14. 7b (see FIG. 4) is formed. 8
is a collapsible cam ring rotatably held on the fixed cylinder 7, and is shown in Fig. 4.
As shown in , a zoom cam groove 8b for driving the zoom cam ring, a second group cam groove 8c for driving the second group cylinder 16, and a parallel cam groove 8d are formed, and an internal gear 8a is provided inside the end thereof. ing. 9 is a motor, and a reduction mechanism 1
The driving force decelerated at 0 is transmitted to the output gear 11,
The internal gear 8a that meshes with the output gear 11 is driven. A pulse sheet 12 is attached coaxially with the motor shaft, and a light and dark pattern is formed around the entire circumference, and a photointerrupter 13 detects the amount of rotation of the motor.

14 is a zoom cam ring, which connects the first group cylinders 15 and 3.
A zoom groove (not shown) is formed to drive the group barrel 17, and a pin 14a fixed to the outer circumference fits into the grooves 8b, 7a, and 7b of the collapsible cam ring 8 and fixed barrel 7, as shown in FIG. Retained. 15 is a first group cylinder that holds the first lens group 3, and as shown in FIG. 1, a pin 15 is fixed to the outer circumference.
a is fitted and held in a groove of the zoom cam ring 14. 16
is a second group cylinder that holds the second lens group, and as shown in FIG.
and is fitted and held in the groove of the fixed cylinder 7. 17 is a third group cylinder that holds the third lens group 5, and a pin 1 fixed on the outer periphery
7a is fitted and held in a groove of the zoom cam ring 14. 1
Reference numeral 8 denotes a fourth group cylinder holding a fourth lens group, which is held by a fourth group base plate 19 and configured to perform a focusing operation by an AF mechanism (not shown). 19 is a 4th group main plate, which is attached to the 1st group cylinder 15. 20 is a mirror with an axis 20a
It is held in the main body 1 so as to be rotatable around the center, and a dowel 20b is fixed to the side surface. A condenser lens 21, a pentaprism 22, and an eyepiece 23 constitute a known finder system.

In FIG. 2, 24 is a lens shutter, the shutter blades of which are driven by an SH (shutter) drive mechanism 25. As shown in FIG. 26 is a mirror up switch, which is composed of sections 27 and 28. Reference numeral 29 denotes a mirror down switch, which is composed of sections 30 and 31. 32 is a mirror drive motor, with pinion gear 3 on the rotating shaft.
3 is fixed. 34 is a reduction gear, which is rotatably attached to the main body 1 around 34a, and the pinion gear 3
It has a large gear part 34b and a small gear part 34c that mesh with the gear 3. A cam gear 35 is attached to the main body 1 so as to be rotatable around 35a, and is attached to the small gear portion 3 of the reduction gear 34.
It has a gear part 35b and a cam part 35b that mesh with the gear part 4c. A transmission lever 36 is rotatably attached to and supported by the main body 1 around a shaft 36a, and has arms 36b and 36b extending in two directions.
36c, a spring 38 is hung on the arm 36b, and the arm 3
6c is in contact with the aforementioned cam portion 35b. 37 is a fan-shaped sector lever, which is held coaxially with the transmission lever 36, has a gear part 37a and an arm 37b, and has a gear part 37a and an arm 37b.
A spring 38 is hung on 7c. The spring 38 is a spring that connects the transmission lever 36 and the sector lever 37, and maintains the state in which the arms 36b and 37b are in contact with each other. Reference numeral 39 denotes a drive lever that is slidably attached to the main body 1 through an elongated hole 39a, and has a rack portion 39b on the side surface that engages with the gear portion 37a of the sector lever 37, and a slit 39c at the tip of the drive lever that engages with the gear portion 37a of the sector lever 37. The dowel 20a is sandwiched between the dowels 20a and is biased downward in the figure by a spring 40 hung on the arm 39d.

FIG. 5 is a schematic diagram of the electronic control system of the camera of this embodiment. 41 is a CPU (that is, a microcomputer) that controls the operation of the camera. 42 is the main switch of the camera, SWO. 43 is a mirror drive circuit that controls the mirror drive motor 32; 44 is a collapsible barrel drive circuit that controls the motor 9. 45 is a pulse sheet 12 and a photo interrupter 13
The amount of rotation of the motor 9 is detected by an encoder detection circuit that drives an encoder comprised of the following. 46 is an SH (shutter) drive circuit that drives the blades of the shutter 24 by the SH drive mechanism 25. 47 is a switch SW1 that is turned on when the release button is pressed halfway, and 48 is a switch SW2 that is turned on when the release button is pressed further.

In the above configuration, FIGS. 1 to 5 and 6
The operation of the camera of this embodiment will be explained with reference to the flowchart shown in FIG.

When the camera is not in use, it is in the state shown in FIG. 1, and the main switch 42 (SWO) (see FIG. 5) is in a standby state. When the SWO is turned on, the microcomputer 41 is activated and first operates the encoder detection circuit 45 and at the same time activates the collapsible barrel drive circuit 44 to energize the motor 9 and drive the collapsible cam ring 8. Then, the collapsible cam ring 8 starts rotating, and the zoom cam ring 14 and the second group cylinder 16 are extended toward the subject via the pins 14a and 16a. Figure 4
(a) and (b) show the situation, and the collapsible cam ring 8
When the pins 14a and 16a begin to rotate in the direction of arrow A, the pins 14a and 16a are regulated by the straight groove 7a, so they move toward the subject (to the left in the figure) by the cam grooves 8b and 8c, as shown in FIG. Therefore, the first group cylinder, third group cylinder, and fourth group cylinder held by the zoom cam ring 8 also move in the same way and are driven to the wide position (states shown in FIGS. 3 and 4(c)). When the wide position is detected, the power to the motor is cut off, the collapsible cam ring 8 stops, and the photographic lens enters the wide state. The wide position is detected, for example, by counting the number of pulses detected by the encoder detection circuit 45, and when a predetermined number of pulses is counted, the motor 9 is stopped and the collapsing drive circuit 44 is stopped.

Next, the mirror drive circuit 43 is activated, and when the mirror drive motor 32 is energized, the cam gear 35 rotates clockwise via the reduction gear 34. By the way, the drive lever 39 is biased downward in the drawing by the biasing force of a spring 40, and a sector lever 37 is gear-coupled to the drive lever and a transmission lever 36 is coaxially coupled to the sector lever by a spring. is biased clockwise, and the arm portion 36c comes into contact with the large diameter portion of the cam portion 35c of the cam gear 35 and stops. When the cam gear 35 rotates clockwise and the contact of the arm portion 36c shifts from the large diameter portion to the small diameter portion of the cam portion 35c, the transmission lever 36 and the sector lever 37 rotate clockwise due to the biasing force of the spring 40, and the drive lever 39 moves downward. Then, the dowel 20b of the mirror 20 is also moved downward by the slot 39c, so the mirror 20 rotates about the shaft 20a and finally reaches the mirror lowered state shown in FIG. 2. At this time, the tip of the mirror 20 pushes the section 30 into contact with the section 31, and the mirror down switch 29 is turned on.

When the downward state of the mirror is detected, the mirror drive motor 32 is stopped and the mirror drive circuit 43 is stopped, but this state is detected by driving the mirror drive motor 32 by an encoder (not shown) in the same manner as in the collapsing operation described above. This is done by counting the number of pulses. Check the status of the mirror down switch 29, and if it is not ON, the mirror 2
0 is not descending and is in an abnormal state, the camera goes into prohibition mode, and if it is in the ON state, it proceeds to the next operation and SH
The drive circuit 46 is activated. Then, the shutter blade 24 is opened by the SH drive mechanism, and the subject light passes through the photographic lens, is reflected by the mirror 20, and is guided to the finder system, allowing the photographer to observe the subject image, and the camera is ready to take pictures. state. In this state, the mirror is shielded from light by the mirror 20 and the main body mirror box (not shown) so that the subject light does not reach the photographic film 2.

A photographing operation is performed when the photographer presses the release button from the above-mentioned photographing ready state, but the details thereof will be omitted since they are not directly related to the intention of the present invention. When SW1 is turned on, the camera performs photometry and distance measurement, and a focus operation is performed based on the distance measurement information. Next, when SW2 is turned on, a release operation is performed, first closing the shutter blade and raising the mirror 20, then opening and closing the shutter blade again based on the photometry information to achieve proper exposure, and then lowering the mirror and raising the mirror 20. The shutter blade is opened and the release operation is completed.

Next, an explanation will be given of the operation when the photographer performs a zoom operation to change the photographing angle of view in the photographing enabled state described above. When a zoom button (not shown) is operated, the motor 9 is energized and the collapsible cam ring 8 is driven again. That is, in the wide state shown in FIG. 4(c), the collapsible cam ring 8 is further driven in the direction of arrow A. Pin 16a has parallel cam groove 8
Since it is located in the region d, even if the collapsible cam ring 8 rotates, the
As shown in (d), the pin 16a does not move, that is, the second group cylinder 1
6 remains in the same position without moving. Also, pin 14a
Since it is no longer restricted by the straight groove 7a and is located in the area of the parallel groove 7b, it moves in the same direction as the arrow A, as shown in FIG. In other words, the zoom cam ring 14 rotates while remaining at the wide position shown in FIG. Then, the pin 15 fitted and held in the cam groove of the zoom cam ring 14
The first group cylinder 15 and the third group cylinder 17 are driven through the second group cylinder 17a.
Since the rotation is restricted by the zoom cam ring 6, the zoom cam ring 8 is extended straight along the cam groove to perform a zoom operation.

The above operation is a zoom operation, and the movement from wide to Tele was explained, but from Tele to Wi
The movement in the de direction is performed by energizing the motor 9 in the opposite direction to that described above, resulting in a similar operation.

Next, the camera is put into a non-use state by turning off the main switch 42. First, S.H.
The drive circuit 46 is activated and the SH drive mechanism 25 drives the shutter blade 24 to close it. After the closure of the shutter blade is detected by a known switch means or the like, the SH drive circuit 46 is stopped. Next, when the mirror drive circuit 43 is activated and the mirror drive motor 32 is energized, the cam gear 35 rotates clockwise via the reduction gear 34, and the large diameter portion of the cam portion 35c pushes up the arm 36c of the transmission lever 36. Rotate the transmission lever 36 counterclockwise.

Since the sector lever 37 is connected to the transmission lever 36 by a spring 38, it similarly rotates counterclockwise so that the gear part 37a moves the drive lever 39 via the rack part 39b of the drive lever 39 to the spring 40. Push it upwards in the figure against the Then, the dowel 20b of the mirror 20 is also pushed upward by the slotted portion 39c, so that the mirror 20
rotates around 20a, and finally reaches the mirror raised state shown in FIG. 3. At this time, the tip of the mirror 20 becomes the section 28.
is pressed to bring it into contact with the section 29, and the mirror up switch 26 is turned on. Similarly to the mirror lowering operation described above, an encoder (not shown) counts the number of drive pulses of the mirror drive motor 32, and when it is detected that the drive required to raise the mirror has been performed, the mirror drive motor 32 is stopped and the mirror is driven. Circuit 43 stops.

At this point, the state of the mirror up switch 26 is checked, and if it is ON, the next operation, the collapsing operation, is carried out, but if it is not ON, the mirror is not in the raised state, so the collapsing operation will cause the photographic lens to collapse. This is prohibited to prevent mirrors from colliding and destroying them. If it is in the ON state, the collapsible barrel drive circuit 44 is activated and the motor 9 is energized in the opposite direction to the collapsible barrel feeding operation described above, thereby rotating the collapsible barrel cam ring in the opposite direction. The operation is similar to the above-mentioned collapsible barrel delivery, but the direction is reversed, and the driving amount is similarly determined by counting the number of pulses of the encoder detection circuit 45. Therefore, when a predetermined number of pulses are counted, the motor 9 is stopped, the collapsing drive circuit 44 is stopped, and at the same time, the encoder detection circuit 45 is also stopped, and the microcomputer 41 returns to the SWO standby state.

FIGS. 7 and 8 are diagrams showing a second embodiment of the present invention, in which parts corresponding to those in the first embodiment described above are denoted by the same reference numerals, and detailed explanations are omitted here. do. The second embodiment is different from the first embodiment in the mirror drive mechanism configuration and detection method, and the mirror drive state is detected using a substrate and a slice having a conductive pattern.

In FIGS. 7 and 8, 50 is a cam gear, which is rotatably held in the main body 1 around 50a.
A gear portion 50b that meshes with the small gear portion 34c of the reduction gear 35
on its outer periphery, and a cam groove 50c is formed on its back surface. Reference numeral 51 denotes a transmission lever, which is rotatably attached to the main body 1 around a shaft 51a, and has a dowel 51b on an arm extending in two directions.
, 51c are fixed, a spring 38 is hung on the dowel 51b, and the dowel 51c is inserted into the aforementioned cam groove 50c. Reference numeral 52 designates a sector lever in the form of a sector, which is held coaxially with the transmission lever 51, and is arranged with a predetermined gap between the gear part 52a that meshes with the rack part 39b of the drive lever 39, the dowel 52b on which the spring 38 is hung, and the dowel 51b. It has a slit 52c that can be inserted with the slit. The cam gear 50 also includes a substrate 53 having a conductive pattern 53a.
is attached, and three sections 54 are mounted on the pattern 53a.
, 55, and 56 are on board.

The lifting and lowering operation of the mirror 20 in the above configuration will be explained. When the mirror drive motor 32 is energized, the cam gear 50 and the base plate 53 rotate clockwise via the pinion 33 and the reduction gear 35. With the rotation, the dowel lever 51c of the transmission lever 51 is moved to the small diameter portion by the cam groove 50c, the transmission lever 51 rotates clockwise, and the sector lever 52 similarly rotates. Then, as in the first embodiment, the drive lever 39 is moved downward via the rack portion 39b, and the mirror 20 is also rotated counterclockwise about the shaft 20a via the dowel 20b to reach the lowered state. This state is shown in FIG. 8(b). At this time, the pieces 55 and 56 are placed on the pattern 53 of the substrate 53, and the piece 54 is removed from the pattern 53. That is, the segments 55 and 56 are in a conductive state, and the segments 54 and 55 are in a non-conductive state. When this state is detected, the mirror drive motor 32 is stopped and the mirror lowering operation is completed. Similarly, when the mirror drive motor 32 is energized and the cam gear 50 is further rotated, the dowel 51c of the transmission lever 51 moves the transmission lever 51 counterclockwise as the cam groove 50c moves from the small diameter section to the large diameter section. This is achieved by rotating. That is, the sector lever 52 rotates counterclockwise in the same way as the mirror lowering operation.
The drive lever 39 moves upward and the mirror 20 moves to the dowel 20.
8 (
The mirror rises as shown in a). At this time, the sections 54 and 55 are placed on the pattern of the substrate 53, and the section 56 is off. That is, the segments 54 and 55 are in a conductive state, and the segments 55 and 56 are in a non-conductive state. When this state is detected, the mirror drive motor 32 is stopped and the mirror raising operation is completed.

By the way, since the dowel of the transmission lever 51 is held by the cam groove 50c, the rotational phase of the cam gear 50 and the rotational phase of the transmission lever 51 always correspond one to one. Similarly, the transmission lever 51 and the sector lever 52 have a one-to-one correspondence due to the combination of the dowel 51b and the slot 52c, and the sector lever 52 and the drive lever 39 have the same correspondence through gear connection, and the drive lever 39 and mirror 2
0 has a one-to-one correspondence due to the combination of the slot 39c and the dowel 20b. That is, since the rotational phase of the cam gear and the rotational phase of the mirror always have a one-to-one correspondence, detecting the phase of the cam gear means detecting the phase of the mirror, that is, whether it is in the raised or lowered state. Specifically, when the intercept 55 is set as a common, when the intercept 55 is in conduction with the intercept 54, the mirror is in the raised state, and when the intercepts 55 and 56 are in the conductive state, the mirror is in the lowered state.

As is clear from the above description, in the second embodiment, the motor stop timing for the mirror raising/lowering operation and the mirror position detection are performed using the section and the conduction pattern. This function is similar to that of the mirror up switch, mirror down switch, and motor drive pulse detection means in the embodiment. The rest of the configuration is the same as the first embodiment, so a description of its operation will be omitted. Furthermore, it is easy to understand that the block diagram and flowchart are the same as in the first embodiment, except that the method of detecting the position of the mirror and the method of detecting the stop timing of the mirror drive motor are different.

FIGS. 9 to 12 are diagrams showing the structure and function of a camera according to a third embodiment of the present invention. The camera of this embodiment differs from the cameras of the first and second embodiments in that the shutter drive mechanism 25 is provided with a shutter switch as shutter state detection means, and the output of the shutter switch is A control means for controlling mirror drive is provided. Therefore, the explanation of the same parts of the camera of this embodiment as those of the cameras of the first and second embodiments will be omitted. Further, in FIGS. 9 to 12, the parts indicated by the same reference numerals as those shown in FIGS. 1 to 8 are the same as the components of the cameras of the first and second embodiments, and therefore the explanation thereof will be omitted.

In FIGS. 9 and 10, reference numeral 24 denotes a two-piece shutter blade, which is rotatably held on a base plate (not shown) about a shaft 24a, and a dowel 60b of a shutter lever 60, which will be described later, is fitted into a long groove 24b. are doing. The shutter lever 60 is rotatably held around a shaft 60a, and has a dowel 60b implanted at the tip of one arm and a gear portion 60c formed at the other end. 61 is a step motor,
A gear 63 that meshes with a pinion gear 62 fixed to the output shaft
The driving force is transmitted to the aforementioned shutter lever 60 via the shutter lever 60 . Reference numeral 64 denotes a shutter switch consisting of sections 64a and 64b, which is configured to be turned on when the shutter is in the closed state.

In this embodiment, this shutter switch 6
The configuration is such that mirror position control is performed in accordance with the output of No. 4. Note that the configurations other than the shutter switch 64 are almost the same as those of the cameras of the first and second embodiments, so a description thereof will be omitted.

FIG. 11 is a schematic diagram showing the configuration of the electronic control system of the camera of this embodiment, and FIG. 12 is a flow chart of the control operation of the electronic control system of the camera of this embodiment.

[0038] Below, FIGS. 1 to 4 and 9 to 12 will be explained.
The operation of this embodiment will be explained with reference to . When the camera is not in use, it is in the state shown in FIG. 1, with the main switch 42 (
When the SWO is turned on in the standby state of the SWO, the microcomputer 41 starts up, first activates the encoder detection circuit 45, and at the same time activates the collapsible barrel drive circuit 44 to energize the motor 9, causing the collapsible cam ring 8 to operate. to drive. Then, the collapsible cam ring 8 starts rotating, and the zoom cam ring 14 and the second group cylinder 16 are extended toward the subject via the pins 14a and 16a. FIGS. 4(a) and 4(b) show this situation, and when the collapsible cam ring 8 starts rotating in the direction of arrow A, the pins 14a and 1
6a is regulated by the straight groove 7a, so the same figure (b
) as shown in cam grooves 8b and 8c on the subject side (left side in the figure)
Move to. Therefore, the first group cylinder, third group cylinder, and fourth group cylinder held by the zoom cam ring 8 also move in the same way and are driven to the wide position (states shown in FIGS. 3 and 4(c)).

When the wide position is detected, the power to the motor is cut off, the collapsible cam ring 8 stops, and the photographing lens
It becomes de state. The wide position is detected, for example, by counting the number of pulses detected by the encoder detection circuit 45, and when a predetermined number of pulses is counted, the motor 9 is stopped and the collapsing drive circuit 44 is stopped. Next, the mirror drive circuit 43 is activated, and when the mirror drive motor 32 is energized, the cam gear 35 rotates clockwise via the reduction gear 34. By the way, the drive lever 39 is biased downward in the drawing by the biasing force of a spring 40, and a sector lever 37 is gear-coupled to the drive lever and a transmission lever 36 is coaxially coupled to the sector lever by a spring. will be biased clockwise,
The arm portion 36c comes into contact with the large diameter portion of the cam portion 35c of the cam gear 35 and is stopped. When the cam gear 35 rotates clockwise and the contact of the arm portion 36c shifts from the large diameter portion to the small diameter portion of the cam portion 35c, the transmission lever 36 and the sector lever 37 rotate clockwise due to the biasing force of the spring 40, and the drive lever 3
9 moves downward.

Then, the dowel 20b of the mirror 20 is also slotted 3.
9c, the mirror 20 is moved downward by 20
The mirror rotates around point a and finally reaches the mirror lowered state shown in FIG. At this time, the tip of the mirror 20 pushes the section 30 and comes into contact with the section 31, and the mirror down switch 29 is turned OFF.
N is given. When the lowered state of the mirror is detected, the mirror drive motor 32 is stopped and the mirror drive circuit 43 is stopped, but this state is detected by controlling the number of drive pulses of the mirror drive motor 32 using an encoder (not shown) in the same way as in the collapsing operation described above. It is done by counting. At this point, check the status of the mirror down switch 29. If it is not ON, the mirror 20 is not lowered and there is an abnormality, so the camera will go into prohibition mode. If it is ON, it will proceed to the next operation and switch to the SH
The drive circuit 46 is activated. Then step motor 6
1 is driven clockwise, and the shutter lever 60 is driven clockwise via a pinion 62 and a gear 63. The dowels 60a rotate the shutter blades 24 in the opening direction through the long grooves 24b, and the open state shown in FIG. The photographer can now observe the subject image. In this state, the mirror is shielded from light by the mirror 20 and the main body mirror box (not shown) so that the subject light does not reach the photographic film.

In the above state, the photographer presses the release button to perform a photographing operation. When SW1 is turned on, the camera performs photometry and distance measurement, and then adjusts F based on the distance measurement information.
An ocus operation is performed. Next, when SW2 is turned on, S
The H drive circuit operates and closes the shutter blade which is in the open state shown in FIG. First, the step motor 61 is driven counterclockwise, and the shutter lever 60 is driven counterclockwise via the pinion gear 62 and gear 63. The shutter blades are rotated in the closing direction via the long grooves 24b, and reach the closed state shown in FIG. 9. At this time, dowel 6
0b pushes the section 64a and brings it into contact with the section 64b, so that the shutter switch 64 is turned on. When the ON state is detected, the SH drive circuit stops, but if the ON state is not detected even after a predetermined period of time has elapsed, the SH drive circuit enters the prohibition mode.

Next, when the mirror drive circuit 43 is activated and the mirror drive motor 32 is energized, the cam gear 35 rotates clockwise via the reduction gear 34, and the large diameter portion of the cam portion 35c is connected to the arm 36c of the transmission lever 36. Push up to rotate the transmission lever 36 counterclockwise. sector lever 3
7 is connected to the transmission lever 36 by a spring 38, so it rotates counterclockwise in the same way, and the gear part 37a moves the drive lever 39 against the spring 40 through the rack part 39b of the drive lever 39. Push upwards in the middle. Then mirror 20
Since the dowel 20b is also pushed upward by the slotted portion 39c, the mirror 20 rotates around the dowel 20a, and finally reaches the mirror raised state shown in FIG. 3. At this time mirror 2
The tip of the mirror 0 presses the section 28 and comes into contact with the section 29, and the mirror up switch 26 is turned on. Similarly to the mirror lowering operation described above, an encoder (not shown) counts the number of drive pulses of the mirror drive motor 32, and when it is detected that the drive required to raise the mirror has been performed, the mirror drive motor 32 is stopped and the mirror is driven. Circuit 43 stops. Here, the state of the mirror up switch 26 is checked, and if it is ON, the next operation, the collapsing operation, is performed, but if it is not ON, it means that the mirror is not in the raised state, so it is determined that there is an abnormality, and the prohibition mode is set. becomes.

Next, the SH drive circuit is activated, and the shutter blades are opened and closed to perform proper exposure based on the above-mentioned photometric information, and then the SH drive circuit is stopped. here,
Check the shutter switch 64, and if it is in the ON state, it will move on to the next operation, the mirror down operation, but if it is in the OFF state, the shutter will not be in the closed state, and the next operation, the mirror up, will cause unintended exposure. In order to prevent this, the mode is set to prohibit. If it is normal, perform the mirror down operation in the same manner as described above, and after the operation is completed, check the state of the mirror down switch 29, if it is in the OFF state, it is determined that it is abnormal and enters the prohibition mode, and if it is in the ON state, proceed to the next operation,
Activate the SH drive circuit. Then, in the same manner as described above, the shutter blades are opened to guide the subject light to the finder, and the camera returns to the SW1 standby state again.

Next, the camera is put into a non-use state by turning off the main switch 42. First, the SH drive circuit is activated to perform the shutter closing operation described above, and if the ON state of the shutter switch 64 is not detected after a predetermined period of time has elapsed, the prohibition mode is entered, and when the ON state is confirmed, the SH drive circuit is stopped. Next, the mirror drive circuit is activated to perform a mirror up operation similar to that described above, and then the mirror drive circuit is stopped.

At this point, the state of the mirror up switch 26 is checked. If it is ON, the next operation, which is collapsing, is performed. If it is not ON, the mirror is not in the raised state, so the collapsing operation will cause the photographic lens to collapse. This is prohibited to prevent mirrors from colliding and destroying them. If it is in the ON state, the collapsible barrel drive circuit 44 is activated and the motor 9 is energized in the opposite direction to the collapsible barrel feeding operation described above, thereby rotating the collapsible barrel cam ring in the opposite direction. The operation is the same as the collapsible barrel delivery described above, but the direction is reversed, and the driving amount is similarly determined by counting the number of pulses of the encoder detection circuit 45. Therefore, when a predetermined number of pulses are counted, the motor 9 is stopped, the collapsing drive circuit 44 is stopped, and at the same time, the encoder detection circuit 45 is also stopped, and the camera returns to the SWO standby state.

FIGS. 13 and 14 show a third embodiment of the present invention, and illustrations and explanations of members having the same functions as those of the first embodiment described above are omitted.

Reference numeral 66 is a shutter blade that is rotatably held around the shaft 24a, and has a long groove 24b into which the dowel 66b of the shutter lever 66 described above is fitted, and a slit hole 66a. 67 is a photoelectric conversion element whose output changes depending on the amount of light received by the light receiving surface 66a;
A light emitting element (not shown) is arranged at an opposing position with .

This embodiment differs from the second embodiment described above in that it adopts a control method based on shutter blade position detection, and in this embodiment, the detection is performed as follows. .

That is, the output of the photoelectric conversion element 6 is detected while the above-mentioned light emitting element is caused to emit light at a constant brightness by a known means such as constant current driving. In the shutter closed state shown in FIG. 13, since the light receiving surface 67a is covered by the shutter blade 66, the output of the photoelectric conversion element 67 is approximately at 0 level. The step motor 6 is installed in the same manner as in the second embodiment described above.
1 is driven clockwise, the shutter blades 24 and 6
6 is rotated in the opening direction, that is, the shutter blade 66 is rotated clockwise. Then the slit hole 66
a is located on the light-receiving surface 67a, and the light emitted from the light-emitting element reaches the light-receiving surface 67a through the slit hole, so that the photoelectric conversion element 67 generates an output. The width of the slit hole becomes wider as the shutter rotates in the opening direction, so that the amount of light received by the photoelectric conversion element 67 increases and the output increases. If the shape of the slit hole 66a is formed so that the output value of the photoelectric conversion element 67 is proportional to the rotation angle of the shutter blade, it is possible to detect the rotation angle of the shutter blade. Further, if the shape of the slit hole 66a is formed so that the output value of the photoelectric conversion element 67 is proportional to the opening amount of the shutter, it is possible to detect the exposure amount by integrating the output value. In any case, by using the output value of the photoelectric conversion element 67, exposure control can be performed. Figure 14
FIG. 2 is a diagram showing a fully open state of the shutter blade.

By the way, in the shutter closed state shown in FIG. 13, since the light receiving surface 67a of the photoelectric conversion element 67 is covered by the shutter blade 66 as described above, the output of the photoelectric conversion element 67 is approximately at the 0 level. Therefore, by also detecting this level, it is possible to detect the shutter closed state.

[0051] In this embodiment, as explained above,
The shutter closed state is detected, and the other operations are the same as those in the first embodiment, so a description thereof will be omitted here.

[0052]

As described above, since the camera of the present invention is provided with mutual control means for the mirror and the shutter, it is possible to realize a camera in which there is no possibility of unintended exposure.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view showing a camera according to a first and third embodiment of the present invention when not in use.

FIG. 2 is a schematic vertical cross-sectional view showing the camera shown in FIG. 1 in a ready state for photographing.

FIG. 3 is a diagram showing the state of the camera when photographing.

FIG. 4 is a diagram showing the relative positional relationship between a cam and a driven pin of the lens moving mechanism of the camera.

FIG. 5 is a diagram showing a schematic configuration of an electronic control system of the camera.

FIG. 6 is a flowchart of control operations in the electronic control system of the camera.

FIG. 7 is a vertical cross-sectional view of the camera according to the second embodiment of the present invention when photographing.

FIG. 8 is an enlarged view of a portion of FIG. 7, showing an example of a mirror position detection means.

FIG. 9 is a diagram illustrating an example of shutter state detection means installed in a camera according to a third embodiment of the present invention, and shows a shutter closed state.

FIG. 10 is a diagram showing the shutter open state in the shutter and shutter state detection means shown in FIG. 9;

FIG. 11 is a schematic diagram of the electronic control system of the camera of the third embodiment.

FIG. 12 is a flowchart of control operations in the electronic control system of the third embodiment.

FIG. 13 is a diagram showing a shutter closed state in a modified embodiment of the shutter state detection means.

FIG. 14 is a diagram showing a shutter open state of the shutter and shutter state detection means shown in FIG. 13;

[Explanation of symbols]

1...Camera body
3 to 6...Photographing lens 7...Fixed barrel
8... Collapsible cam ring 9... Motor
10...Photo interrupter 10...Deceleration mechanism
11...Gear 12...Pulse sheet
14... Zoom cam ring 15... 1st group cylinder
16...2nd group cylinder 17...3rd group cylinder
18...Fourth group cylinder 20...Movable mirror 21...Condenser lens 22...Penta prism 2
3...Eyepiece lens 24...Shutter
25...Shutter drive mechanism 26...Mirror up switch 29...Mirror down switch 32...Motor
33... Pinion gear 34... Reduction gear
35...Cam gear 36...Transmission lever
37... Sector lever 38... Spring
39... Drive lever 39c... Slot 41... CPU (microcomputer) 42... Main switch (SWO) 47... Release button responsive first switch (SW1) 48
...Release button responsive second switch (Sw2) 50...Cam gear 51
...Transmission lever 50c...Cam groove
52... Sector lever 52c... Slit split
54-56... Section 53a... Continuity pattern
60...Shutter lever 61...Step motor 62
…Pinion 63…Gear 64…Shutter switch (shutter state detection means) 6
6...Shutter blade 66
a...Slit hole

Claims (3)

[Claims] 1. A mirror movable between a first position on the photographing optical axis behind the photographing lens and a second position remote from the photographing optical axis, and a lens shutter disposed between the photographing lens. 1. A camera comprising: a mirror/shutter control means for controlling mutually related operations of the mirror and the lens shutter. 2. The mirror/shutter control means includes a mirror position detection means for detecting that the mirror is at the first position, and a mirror position detection means for detecting that the mirror is at the first position. 2. The camera according to claim 1, further comprising shutter control means for allowing the lens shutter to open. 3. The mirror/shutter control means includes a shutter state detection means for detecting that the lens shutter is in a fully closed state, and a shutter state detection means for detecting that the lens shutter is in a fully closed state. 2. A camera according to claim 1, further comprising mirror control means for allowing said mirror to move to said second position after said mirror is moved to said second position.