JPH0727157B2 - Camera system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a camera system, and more particularly to an exposure control and drive system for a camera with interchangeable lenses.

[Conventional technology]

The non-interchangeable lens type 35 mm camera is generally called a compact camera, and this type of camera is equipped with a so-called lens-shutter device, which serves both as a shutter and an aperture, as an exposure control device. Further, it has become common to automatically wind and rewind the film by using the power source of the camera. Furthermore, even in so-called single-lens reflex cameras with interchangeable lenses, automatic exposure equipment, automatic film winding equipment, automatic focus adjustment equipment,
Various mechanisms such as an automatic film rewinding device are housed in one camera, and the operation of the mechanism is automatically performed by one power source. Therefore, since the power supply voltage is limited, complicated operations must be performed in time series and the power supply must be used efficiently.

Particularly, in recent years, it has been proposed that the mirror drive and the diaphragm drive are performed by separate motors, but if both drives are performed at the same time, a large voltage is required, and the capacity of the power supply increases, which is not suitable for a camera. Further, there is a drawback that a malfunction occurs when the power supply voltage drops at a low temperature or the like.

〔Purpose〕

The present invention solves the above-mentioned drawbacks of the prior art. The invention of item 1 is a camera system comprising a camera body and an interchangeable lens detachable from the camera body, wherein the camera body comprises a power supply means, The first motor fed from the power supply means and the mirror are moved by the first motor from the first position, which is in the photographing optical path entering state, to the second position, which is in the photographing optical path retracted state, and the second mirror is moved. The interchangeable lens has a second motor and a second motor fed from the power source, and drives the diaphragm from the open state to the narrowed state, and the mirror driving means moves from the position to the first position. A control means for controlling the operation of the first motor and the second motor, the control means having a diaphragm means for driving the diaphragm from the narrowed state to the open state, and the first of the mirrors by the mirror driving means before exposure. From the position The start of the operation to the second position and the start of the drive of the diaphragm from the opening of the diaphragm to the closed state are shifted, and after the exposure, the mirror means moves the second position of the mirror to the first position. The present invention is characterized by a camera system provided with control means for shifting the start of operation to a position and the start of driving of the diaphragm from the narrowed state to the open state, and effectively uses the power source means of the camera body. The purpose is to

Further, the invention of the second aspect is such that the diaphragm motor fed from the power source means of the camera body, and the diaphragm means for driving the diaphragm from the open state to the narrowed state by the diaphragm motor and from the narrowed state to the open state. And an interchangeable lens having a lens side control means for controlling the operation of the diaphragm motor, wherein the camera body is a power source means, a mirror motor fed from the power source means, A mirror driving unit that moves the mirror from the first position, which is in the photographing optical path entering state, to the second position, which is in the photographing optical path retracted state, by the mirror motor, and also moves from the second position to the first position; The camera-side control means controls the operation of the mirror motor, and the camera-side control means moves from the first position of the mirror to the second position by the mirror driving means before exposure. The start of operation is shifted from the start of driving the aperture of the interchangeable lens from the opening of the aperture to the state of aperture reduction, and the exposure is performed from the second position of the mirror to the first position of the mirror by the mirror. Is characterized in that the camera body is controlled so that the start of the operation is shifted from the start of driving the aperture from the narrowed state to the open state, and the power source means of the camera body is effectively used. And

According to a third aspect of the present invention, a power source means, a mirror motor fed from the power source means, and a mirror for retracting the mirror from the first position, which is the shooting optical path entry position, by the mirror motor. An interchangeable lens that is detachable from the camera body having a mirror drive means that moves from the second position to the first position and a camera side control means that controls the operation of the mirror motor. The interchangeable lens includes a diaphragm motor fed from the power supply means of the camera body, and diaphragm means for driving the diaphragm from the open state to the narrowed state by the diaphragm motor and from the narrowed state to the open state. And a lens side control means for controlling the operation of the diaphragm motor, and the lens side control means starts driving the diaphragm from the open state to the narrowed state by the diaphragm means before exposure. Shifting the movement of the mirror from the first position to the second position by the mirror driving means in the camera body, and driving the aperture from the narrowed state to the open state by the aperture means after exposure. Starting from the second position of the mirror by the mirror drive means to the first
It is characterized by an interchangeable lens that is controlled so as to be shifted from the start of the operation to the position, and its purpose is to effectively utilize the power supply means of the camera body.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS.

FIG. 1 is a configuration diagram schematically showing the configuration of the essential parts of a camera, an electric drive device for a lens, and a circuit according to the present invention. 1
Is a camera body, 2 is an interchangeable lens body detachably attached to the camera body 1, and is connected to a camera mount 1a and a lens mount 2a, respectively. 3 is a mirror, 4 is a pentaprism, 5 is an eyepiece lens, and 6 is a light receiving element for photometry. Reference numeral 7 denotes a photometric calculation circuit, which is connected to the film sensitivity information input circuit 8, the shutter control circuit 9, and the microcomputer 10. Reference numeral 34 is a focal plane shutter, 3a is a mirror rotation shaft, and 3b is an operation pin facing the mirror drive cam 11. A mirror driving motor 12 is connected to the motor drive circuit 13. A film winding and rewinding motor 14 is connected to the motor drive circuit 15. A distance measuring sensor 16 is connected to the distance measuring calculation circuit 17. Reference numeral 18 is a battery for operating the entire camera system, 19 is a main power switch, and 20 is a DC / DC converter, which is connected from the battery 18 to the microcomputer 10. Reference numeral 21 is a photometric distance measuring switch, and 22 is a release switch. Reference numeral 23a denotes a contact pin group on the camera side, which is arranged near the mount 1a. twenty three
Reference numeral b denotes a contact pin group on the lens side, which faces the contact pin group 23a on the camera side. G ₁ and G ₂ are photographic optical lenses, and a photographic optical system 25 is formed with an electrically driven diaphragm 24 having a diaphragm driving motor (not shown). Reference numeral 26 is a lens drive motor used for focus adjustment, which is connected to a lens drive circuit 27, a gear 26a is attached to the output shaft, and is further interlocked with a pulse plate 28. Reference numeral 29 is a photoreflector which is arranged so as to face the pulse plate 28 and is connected to the waveform shaping circuit 30. A diaphragm driving circuit 31 is connected to the microcomputer 32. 33 is an aperture open detection switch, which is a microcomputer
Connected to 32.

Further, 35 and 36 are voltage detection circuits.One voltage detection circuit 35 is connected between the micro computer 10 and the battery 18, and the other voltage detection circuit 36 is connected between the micro computer 32 and the diaphragm drive circuit 31. ing.

Next, the operation of the camera system of the present invention having the above configuration will be described.

First, turn on the main power switch 19 of the camera body 1
By activating the / DC converter 20, a constant voltage at which the microcomputer 10 can be operated is supplied. When the photometric distance measuring switch 21 is pressed, the light amount detected by the photometric light receiving element 6 is transmitted to the photometric calculating circuit 7 and the exposure amount is stored by a known method.

On the other hand, the photometric distance measuring switch 21 also serves as a trigger switch for automatic distance measuring. When the switch 21 for photometry and distance measurement is pressed, the distance measurement sensor 16 is instructed by the instruction of the micro computer 10.
Is operated, the distance measurement calculation circuit 17 performs distance measurement calculation by a known method to determine the amount of extension of the lens, and known serial communication with the lens side microcomputer 32 is performed to rotate the drive motor 26 to the lens drive circuit 27. Directional shooting optics
Move 25 in the direction of the optical axis. At this time, the pulse plate 28 rotates at the same time in response to the movement of the lens, and the movement amount of the lens can be detected by reading the pulse number with the photoreflector 29. Therefore, as described above, shooting is performed according to the movement amount instructed by the camera. Move the optical system 25 and stop the lens at the in-focus position. In general, distance measurement is performed again, and when it is determined that the focus state is achieved, the camera side displays the focus state or generates the focus sound.

Next, the operation thereafter will be described with reference to the timing chart shown in FIG. 2. The operation up to this point is performed before the zero point in FIG. In FIG. 2, the horizontal axis represents time and the vertical axis represents each item.

When the release switch 22 is pressed at point 0 in FIG. 2, the microcomputer 10 causes the mirror drive motor to move.
The motor drive circuit 13 is energized to rotate 12 and the mirror drive cam 11 is rotated to push up the operation pin 3b (point a) to raise the mirror (photographing optical path retracted position).
And hold (point d), and at point b, which is delayed from point a by a certain time, known serial communication is performed between the camera microcomputer 10 and the lens microcomputer 32 through the contact pin groups 23a and 23b to perform photometry. Instructs the lens to set the aperture value according to the amount. The diaphragm driving circuit 31 controls the electrically driven diaphragm 24 based on the diaphragm setting value designated by the camera. At this time, a certain time difference is provided between the mirror raising operation point (point a) and the diaphragm driving operation point (point b) because a large current flows to the mirror driving motor 12 immediately after the power is turned on. The limited power source is effectively used by avoiding driving the diaphragm. Further, before the point b, the aperture open detection switch 33 is in the open state, and after the point b, that is, when the aperture is started, the detection switch 33 is closed and it is determined whether or not the open state.

The aperture open detection switch 33 is mechanically turned on in the embodiment.
Although the description has been made with the OFF switch, other state detection switches, such as MR element and photo sensor, may be used properly according to the situation. At point c, the aperture has been stopped down to the set aperture. When the mirror ascends at the point d, the exposure operation is started from the point e, that is, the shutter is operated up to the point f with a slight margin. At point f, the mirror driving motor 12 is energized based on the exposure completion signal to lower the mirror 3 (at the position where the photographing optical path enters), and at point g, the mirror 3 is returned to the photometric state. At this time, the mirror drive motor 12 is energized for the same reason as when the mirror 3 is raised, and after a certain time, the return drive of the aperture is started from the point h, and when the aperture is completely returned to the open state, the aperture open detection is performed. Switch 33 is open. This is point i. Further, the mirror driving motor 12 also serves as a mechanical charge of the focal plane shutter 34 and operates up to the point J. The signal at the point i passes through the microcomputer 32 and the microcomputer 10 on the camera side.
Then, the motor drive circuit 15 is instructed to operate and the film winding / rewinding motor 14 winds the film. This film winding operation is completed at point k, and the camera sequence returns to the original operation, and the operations of photometry and distance measurement are started.

What has been described above is a series of photographing operations of the camera system of the present invention. A more complete sequence regarding the electrically driven diaphragm will be described below using the flow chart of FIG.

In FIG. 3, when the main power switch 19 is turned on at step 51, the DC / DC converter 20 is operated at step 52 and the microcomputers 10 and 32 are operated at step 53. At step 54, whether or not the electrically driven diaphragm 24 is opened is detected by the diaphragm open detection switch 33. If the diaphragm blades are not opened due to some reason in the optical path, at step 55, the diaphragm drive circuit 31 is returned to the return direction. Give instructions to move and step
When the aperture open detection switch 33 detects that the aperture is open at 56, the return drive of the aperture blades is stopped. By closing the main power switch 19 of the camera as described above, the aperture is opened. Here, when it is determined that the aperture does not return to the open state, when the number of pulses exceeds a certain value, energization is terminated and a reset display is displayed on the camera.

Next, at step 57, the photometry and distance measuring switch 21 is turned on, and at step 59, the state of the diaphragm is confirmed. Since the operations of steps 59 to 61 are the same as the operations of steps 54 to 56 described above, the description thereof will be omitted here. After performing photometry and A / D exchange in step 62, the calculation result is stored in step 63. Step
The release switch 22 is turned on at 64, and the mirror drive motor 12 is rotated at step 65 to raise the mirror 3. The energization is continued until the completion of the raising of the mirror 3 is detected at steps 66 to 67, and the energization is stopped when the completion of the raising of the mirror 3 is detected. Further, at the same time when the mirror drive motor 12 is energized at step 65, a timer (not shown) starts to operate, and at step 68
After waiting for a certain time at step 69, the power supply voltage in the camera is checked by the voltage detection circuit 35 at step 69, and if the voltage is less than a predetermined voltage, wait at the step 70 for a certain time, and if it is more than the predetermined value, proceed directly to step 71, It is determined whether or not the aperture controlled by this step 71 may remain open or needs to be reduced. Here, when the aperture can be left open, the shutter front curtain is started in step 76, which will be described later, but when it is necessary to reduce the aperture, step 72 transmits the number of aperture pulses from the camera to the lens. Electric drive diaphragm 24 in step 73
The aperture open detection switch 33 detects whether or not is open, and if it is open, a step 74 keeps the mirror rising complete state and a step 75 stops the sequence to notify the user of the accident. If the aperture open detection switch 33 is closed at step 73, the shutter front curtain is started at step 76, and the shutter rear curtain is started at step 77.
At step 78, the mirror drive motor 12 is energized to lower the mirror based on the shutter trailing curtain completion signal, and at step 80 it is checked whether or not the mirror 3 is lowered. If it is, step 81 With mirror drive motor
Stop energizing 12 and step 79 if not down.
Return to. Further, in step 82, a timer (not shown) is activated and waits for a certain period of time, and in step 83 the power supply voltage inside the camera is checked by the voltage detection circuit 35. If it is above, the process goes directly to step 85, and in step 85, an aperture open command is sent to the lens, and in steps 86 to 89, the aperture open detection switch 33 is activated every time the aperture drive motor is energized for one pulse in the opening direction from the small aperture. When the switch 33 is closed, it detects whether or not the number of energizing pulses is 100 or more.When the number is less than or equal to 100, the energizing is continued, and when the number is more than 100, the step 75 is performed. Then, the sequence is stopped and the user is informed of the accident. When the aperture open detection switch 33 is open at step 87, the flow of current to the aperture drive motor is stopped at step 89, the drive of the film winding / rewinding motor 14 is started at step 90, and at step 91. When the completion of film winding is detected, a series of photographing sequences is ended. After that, the sequence returns to the step 57 where the photometric distance measuring switch 21 is turned on.

Incidentally, in the above-mentioned flow chart, the electric drive diaphragm 24 is operated after waiting for a certain period of time as shown in the steps 68 and 82 both when the mirror 3 is raised and when it is lowered. Therefore, as a result, the timing of the energization peak to each motor for driving the mirror and driving the diaphragm is deviated. Therefore, it is possible to prevent the overlapping of the flush currents at the start of energization and to effectively utilize the limited power supply voltage. Also, as described above, after waiting for a certain period of time at steps 68 and 82, the power supply voltage is checked at the next steps 69 and 83, respectively.
4 waits for a certain time, but when the voltage of the battery 18 is unexpectedly low due to low temperature etc., the timing of the peak of energization to each motor for mirror drive and diaphragm drive is further increased. It is designed to be shifted.

〔The invention's effect〕

As described above, according to the present invention, power is supplied to the first motor for driving the mirror in the camera body and the second motor for driving the diaphragm in the interchangeable lens by the power supply means of the camera body. , The mirror is in the shooting optical path entry state 1
The drive start of the first motor for moving from the position of 2 to the second position which is the retracted state of the photographing optical path and the drive start of the second motor for driving from the opening of the diaphragm to the stop. , The drive start of the first motor for moving from the second position to the first position and the drive start of the second motor for driving from the narrowed state to the open position are shifted. As a result, the timings of the rush currents at the time of starting the driving of the first motor and the second motor are shifted, and the power supply means is used very effectively, so that the battery life is extended and the internal circuit (for example, a microcomputer) is It is possible to prevent malfunction.

Further, as shown in the embodiment, by changing the time until the start of energization of both motors depending on the value of the power supply voltage, it is possible to cope with a sudden decrease in the power supply voltage at a low temperature, for example.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention,
FIG. 1 is a configuration diagram schematically showing the main components of a camera and an electric drive device for a lens and a circuit, FIG. 2 is a timing chart diagram, and FIG. 3 is a flow chart diagram. 1 …… Camera body 2 …… Interchangeable lens body 7 …… Metering calculation circuit 18 …… Battery 24 …… Electric drive diaphragm 31 …… Aperture drive circuit 33 …… Aperture open detection switch 35,36 …… Voltage detection circuit

Claims (3)

[Claims] 1. A camera system comprising a camera body and an interchangeable lens detachable from the camera body, wherein the camera body comprises a power source means, a first motor fed from the power source means, and the first motor. The motor moves the mirror from the first position in which the photographing optical path is intruded to the second position in which the photographing optical path is retracted, and at the same time, moves from the second position to the first position.
The interchangeable lens is driven by the second motor and the second motor fed from the power source means to drive the diaphragm from the open state to the narrowed state, and from the narrowed state to the An aperture drive unit for driving the aperture to an open position, for controlling the operations of the first motor and the second motor, the first drive unit before the exposure from the first position of the mirror by the mirror drive unit; The start of the operation to the position 2 and the start of driving of the diaphragm from the opening to the narrowed state by the diaphragm means are shifted, and the second to the first position of the mirror by the mirror means after exposure is shifted. The camera system is provided with a control unit that shifts the start of the operation of the diaphragm and the start of driving the diaphragm from the narrowed state to the open state. 2. A diaphragm motor fed from a power source means of a camera body, a diaphragm means for driving the diaphragm from an open state to a narrowed state by the diaphragm motor, and for driving the diaphragm from the narrowed state to the open state, and for the diaphragm. A camera body having an interchangeable lens having lens-side control means for controlling the operation of a motor, wherein the camera body is composed of a power source means, a mirror motor fed from the power source means, and a mirror motor. A mirror drive unit and a mirror motor for moving the mirror from the first position, which is in the state of entering the photographing optical path, to the second position, which is in the state of retracting the photographing optical path, and moving from the second position to the first position. Of the mirror from the first position to the second position by the mirror driving means before exposure. The start of the interchangeable lens is shifted from the opening of the diaphragm by the diaphragm means to the start of driving the diaphragm, and after the exposure, the mirror means moves the second position of the mirror to the first position. A camera main body, wherein the operation start is controlled so as to be shifted from the start of driving of the aperture from the narrowed state by the aperture means to the full aperture. 3. A power source means, a mirror motor fed from the power source means, and a mirror for moving the mirror from the first position, which is the photographing optical path entry position, to the second position, which is the photographing optical path retracted state, by the mirror motor. An interchangeable lens that is detachable from a camera body having a mirror drive unit that moves and moves from the second position to the first position and a camera-side control unit that controls the operation of the mirror motor. The interchangeable lens is a diaphragm motor fed from the power supply means of the camera body, a diaphragm means for driving the diaphragm from an open state to a narrowed state by the diaphragm motor, and a diaphragm means for driving the diaphragm from the narrowed state to the open state. A lens-side control means for controlling the operation of the motor for driving the lens-side control means, and the lens-side control means starts the driving of the diaphragm from the opening of the diaphragm to the closed state by the diaphragm means before exposure. The start of driving the mirror from the first position to the second position of the mirror by the mirror driving means in the camera body and the driving of the diaphragm from the narrowed state to the open state by the diaphragm means after exposure are started. Is controlled so as to shift from the start of the movement of the mirror from the second position to the first position by the mirror driving means.