JPS58214133A - Automatic servo diaphragm device having shutter function - Google Patents

Abstract

PURPOSE:To realize an application of the titled device to both movie camera and still camera, by using a common automatic servo diaphragm circuit. CONSTITUTION:The 1st changeover switch 10 is connected to a contact (a) when the camera is applied as a movie camera, and therefore the output given from an image pickup element 5 is applied to an automatic servo diaphragm circuit 13. In this case, the shutter blade caliber of a diaphragm shutter mechanism 3 is controlled in response to the luminance of a field to be photographed. When this camera is applied as a still camera, the switch 10 is connected to a contact (b). Then a low voltage level of the 2nd changeover switch 20 is applied to the circuit 13. Thus the shutter blade is opened. When the shutter is released, a contact (c) is set at a high voltage level. Then the shutter blade is closed. In this case, the open/close time of the shutter blade is controlled by the signal supplied from a photodetecting element 18 and in response of the luminance of the field to be photographed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a servo automatic aperture device having a shutter function, and more specifically, when used as a movie camera, a servo automatic aperture device is connected to an image sensor, and the shutter blades that also serve as an aperture are used to adjust the field brightness. When used as a still camera, the servo automatic aperture is switched and connected to a time-setting circuit that opens and closes the shutter blades to obtain an appropriate exposure time depending on the brightness of the field. This invention relates to a servo automatic diaphragm device V having a shutter function in which a portion of a servo automatic diaphragm mechanism and a shutter mechanism are shared.

A programmable shutter using a servo mechanism has also been proposed in Japanese Patent Laid-Open No. 53-56021 filed by the present applicant, but such a programmable shutter has shutter blades and shutter blades similar to general electromagnetic drive shutters. Not only does the opening/closing ring reciprocate at a predetermined time, but also the 4 m&m upper movable ring, which has an inertial force, has to be reciprocated, resulting in the disadvantage that a substantially high shutter speed cannot be obtained.

In addition, in order to keep the aperture blades at an appropriate aperture diameter of 1" according to the brightness of the field, the field brightness information voltage obtained by receiving the field light is compared with the reference voltage, and the difference in opening and closing the aperture blades is compared with the reference voltage. A servo automatic iris that includes a dynamic aperture intensifier has also been proposed, but such a servo automatic iris cannot open and close the aperture blades at a predetermined opening time to operate as a shutter to obtain proper exposure. .

In view of the above, the present invention makes it possible to use the same unit as a movie camera and a still camera by slightly modifying the servo automatic aperture so that it has the function of a program shutter. It is an object of the present invention to provide a servo automatic diaphragm device having a shutter function capable of obtaining a high shutter speed that cannot be obtained with a conventional electromagnetically driven program shutter.

The servo automatic diaphragm device having a shutter function according to the present invention is connected to a drive motor, and is opened and closed by a shutter blade opening/closing ring operated by the energization of the drive motor, and also cooperates with a shutter blade closing actuating coil and energized by the shutter blade opening/closing ring. An electromagnetically driven aperture shutter mechanism that has shutter blades that also serve as an aperture that is fully closed by a shutter blade closing ring operated by the shutter blade opening/closing ring, regardless of the operation of the shutter blade opening/closing ring, and an imaging system that receives field light through this aperture shutter mechanism. an image pickup device, a still image recording unit connected to the image pickup device, and the drive motor;
The given information voltage is compared with the reference voltage, and when the given information voltage is lower than the reference voltage, the shutter blade is closed, and when it is higher, the shutter blade is opened, and when the voltage difference between the two becomes zero, The servo automatic aperture circuit maintains the shutter blade at the shutter blade aperture position at that time, and the servo automatic diaphragm circuit selectively connects the output of the image sensor to a circuit that generates an output at a low voltage level when the field brightness is high. A first changeover switch having a first contact connected to the diaphragm circuit and a second contact of the first changeover switch are connected to each other, and are normally kept at a low voltage level, and are switched to a high voltage level in conjunction with the shutter release. The second switched to voltage level
a change-over switch; a light-receiving element that receives field light and generates a field brightness information signal; When the second changeover switch is at a low voltage level, the shutter blade is closed by the servo automatic diaphragm circuit, and when the voltage level is changed to a high voltage level, the shutter blade is opened (and the light receiving The field brightness information signal of the element is input, and after a period of time corresponding to the field brightness has elapsed, the pulse generation circuit is activated to energize the shutter blade drive coil to close the shutter blades and adjust the field brightness. The present invention is characterized by comprising a time-setting circuit that causes the still image recording section to obtain a still image by applying appropriate exposure accordingly.

With this configuration, by providing a time setting circuit that can be switched and connected to the servo automatic iris circuit, a common servo automatic iris can be used as a servo automatic iris, and a programmable shutter that obtains an appropriate shutter exposure time can be used. It can also be used as

Furthermore, according to the present invention, the shutter blade closing ring is biased to the shutter blade fully closed position by the first spring, and the shutter blade can be opened and closed by the locking lever against the action of the first spring. The locking lever is attracted by a second spring and a magnet which act to bias the locking lever into a position for unlocking the shutter blade closing ring. has a magnetic piece that locks the shutter blade closing ring in a position where the shutter blades can be opened and closed against the action of a second spring, and the shutter blade closing actuation coil cooperates with the magnet to energize the shutter blade closing ring. When the lock is released, the magnetic force of the magnet is weakened to release the attraction of the magnetic piece, and the locking lever is biased to the position where the lock is released by the action of the second spring. is operatively connected to a motor, and when the set motor is energized, pushes the shutter blade closing ring to a position where the shutter blade can be opened and closed against the action of the first spring, and the shutter blade closing ring is operatively connected to a motor. an actuating lever device operatively connected to the shutter blade closing ring and the locking lever for pushing the locking lever so as to lock the shutter blade in a position in which the shutter blade can be opened and closed; A set motor energizing circuit is connected to the set motor energizing circuit via a delay circuit, so that when the first switching lever is switched to the second contact point, the second switching lever is switched to the second contact point.
After the switching lever is switched to a high voltage level in conjunction with the shutter release and the shutter blades are opened and closed by the timing circuit, the set motor is energized after a predetermined delay time has elapsed by the delay circuit and the locking lever is activated. The shutter blade closing ring can be locked in a position where the shutter blades can be opened and closed, and thereby the shutter blade closing ring can be closed separately from the shutter blade opening and closing ring that allows the shutter blades to open and close when used as a program shutter. The shutter blade opening/closing ring has a dog's inertia that operates to open the shutter blade by the ring, and the shutter blade closing ring operates extremely quickly during the opening operation of these items without requiring a rapid reversal of the drive motor. This allows the shutter blades to be closed quickly, resulting in a high shutter speed.

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Referring to FIG. 1, an embodiment of a movie/still camera incorporating the present invention is shown (this camera has a zoom lens 1, a half mirror 2, an aperture shutter according to the present invention, Mechanism: 3. Master lens 4, for example, a charge-coupled device COD (Charge-Coupled Device)
It works to generate and hold a charge distribution corresponding to an object image such as a device, and sequentially scan and move it.
an image sensor 5; an image intensifier 6 that receives the output of the image sensor 5 and amplifies the image; a rectifier circuit 7; a low-pass filter 8; an inverter 9; a first contact α connected to the inverter 9; The changeover switch 10 includes a drive motor 11 for driving the shutter blade opening/closing ring of the aperture shutter mechanism 3 as described later, and the output of the inverter 9 when the first changeover switch -f':10 is connected to the contact α. It receives a voltage and compares it with a reference voltage. If the brightness of the field is high and therefore the output of the image sensor 5 is at a high level, but the output voltage of the inverter 9 that inverts this is lower than the reference voltage, the aperture is adjusted. The shutter blade opening/closing ring operates in the direction to close the shutter blade that also serves as the diaphragm of the shutter mechanism 3. Conversely, when the field brightness is low and the output voltage of the inverter 9 is higher than the reference voltage, the shutter blade opening/closing ring operates in the direction to open the shutter blade. The drive motor 11 is driven to adjust the amount of light received by the image sensor 5 to control its output, and when both voltages become equal, the drive motor 11 is deenergized to adjust the shutter blade to the current aperture. The servo automatic diaphragm circuit 13 includes a known servo automatic diaphragm circuit 13 having a differential amplifier 12 held at The output is an arithmetic amplifier whose output is connected to the differential amplifier 12]
The rotation speed of the drive motor 110 is fed back to the input of the drive motor 110, thereby reducing the shutter opening/closing speed.

Another half mirror 16 is arranged on the reflection optical path of the half mirror 20, and a normal finder optical system 17 is arranged on the reflection optical path of the half mirror 20, and a light receiving element 18 such as a photoresistive element is placed on the transmission optical path. is arranged, and its output is connected via a photocurrent amplifier 19 to the contact point of the first changeover switch 10 described above.

The second changeover switch 20 configured as a disconnection switch is grounded via a resistor 21 and is connected to the power supply voltage Vcc so as to be disconnectable.
This changeover switch 2o is connected in conjunction with the shutter release operation, and is normally in the cutoff position, applying a low voltage level to the connection point C with the resistor 21, but it is connected in conjunction with the shutter release operation. A high voltage level is applied to connection point C when the connection point is switched to the connected position. The connection point C is connected to the contact of the first changeover switch, and is also connected to the base of a transistor 22 whose emitter is connected to the power supply voltage Vcc, and the collector of the transistor 22 is connected to the photocurrent amplifier 19 described above. has been done. An integrating capacitor 23 is placed in parallel with the emitter and collector of the transistor 22, and when the transistor 22 is in a non-conducting state, the capacitor 23 generates a current according to the field brightness defined by the photocurrent amplifier 19. It is charged to a field brightness information voltage corresponding to Ip. One end d of the capacitor 23 is connected to one input of the comparator 24, and the other input is a reference voltage consisting of a series circuit of resistors 25 and 26, with one end connected to the power supply voltage Vcc and the other end grounded. The output of the comparator 24 is connected to the input of a single pulse generator 270, the output of which is connected to the base of a transistor 28, the emitter of which is grounded. and the collector has one end connected to the power supply voltage Vcc.
The shutter blade closing actuation coil 29 is connected to the other end of the shutter blade closing actuation coil 29 . This shutter blade closing actuating coil 29 is used as a still camera by electromagnetically cooperating with a magnetic piece of a locking lever that locks the shutter blade closing ring of the aperture shutter mechanism 30 in a position where the shutter blades can be opened and closed, as described later. As will be described later, the shutter blade is once closed and then opened, and after a time corresponding to the brightness of the field, the locking lever is released so that the shutter blade closes by the energization of the shutter blade closing actuating coil 29, and the shutter is closed. Move the blade closing ring to the shutter blade fully closed position.

A still image recording section 3o is connected to the output of the video intensifier 6 to record a still image.

As will be described later, when the shutter blade is used as a still camera, the output of the comparator 24 is used to return the shutter blade opening/closing ring to the position where the shutter blade can be opened and closed again and to lock the shutter blade in that position using the locking lever. is connected to a set motor drive circuit 32 via a delay circuit 31. The operation of the set motor drive circuit 32 will be described later.

As shown in FIG. 2, the aperture shutter mechanism 3 described above includes a shutter blade opening/closing ring 33 rotatably supported on a base plate (not shown) and a shutter blade closing ring 34, formed on a shutter blade 35 which also serves as an aperture. The elongated hole 35α is slidably fitted into a pin 33a installed in the shutter blade opening/closing ring 33, and the round hole 35b provided in the shutter blade 35 is fitted into a pin 344 installed in the shutter blade closing ring 34. Shutter blade closing ring 3
4 is biased clockwise by a spring 36, but normally a locking shoulder 34h formed on the ring 34 is pressed against the spring 3 by a locking pawl 38α of a locking lever 38 pivotally supported on a shaft 37.
6, the shutter blades shown in the figure are locked in a position where they can be opened and closed. Shutter blade opening/closing ring 33
A protruding arm 33b is formed in the protruding arm 33b, and a long hole 33C formed in the protruding arm 33h is slidably fitted into the bin 11α which is rotated together with the rotation of the drive motor 110 described above.

Therefore, as shown in FIG. 2, when the drive motor 11 rotates counterclockwise with the shutter blade closing ring 34 locked by the locking lever 38, the shutter blade opening/closing ring 33 rotates clockwise. The shutter blade 35 rotates clockwise around the pin 34α to open the shutter blade 35, and rotates in the opposite direction to the above-mentioned direction to close the shutter blade 35.

However, when the shutter blade 35 is opened, the locking lever 38 closes the shutter to the blade closing ring 34.
When the lock is released, the shutter blade closing ring 34 is rapidly rotated clockwise by the action of the spring 36, and the pin 33 is rotated rapidly at the position of the shutter blade opening/closing ring 33 at that time.
The shutter blade 35 is rapidly moved to the fully closed position by being regulated by the elongated hole 35α that is slidably fitted to the opening 35a.

The locking lever 38 is biased by a spring 39 in the direction of releasing the lock of the shutter blade closing ring 34;
The magnetic piece 4° provided on the locking lever 38 is attracted by the permanent magnet 41, so that the locking lever 38 is normally held by the spring 3.
The shutter blade is closed against the action of the ring 34 and held in the locking position of the ring 34. The above-mentioned shutter blade closing actuation coil 29 is wound around this permanent magnet 41, and when the shutter blade closing actuation coil 29 is energized, the magnet 4
The magnetic force of 1 is canceled out and weakened, the attraction of the magnetic piece 40 is released, and the locking lever 38 is rotated counterclockwise by the action of the spring 39 to release the locking of the shutter blade closing ring 34. 42 and is held in contact with it.

After the locking of the shutter blade closing ring 34 by the locking lever 38 is released and the shutter blades 35 are closed, the shutter blade closing ring 34 is returned to the position where the shutter blades can be opened and closed against the action of the spring 36, and the shutter blades are locked. A set motor 42 driven by the set motor drive circuit 32 is provided to move the stop lever 38 to the locking position of the shutter blade closing ring 34, and a cam 43 is fixed to the drive shaft of the set motor 42. The right edge 45b of the operating lever 45, which has a guide groove 45α that slides into the guide bin 44 and is movable from side to side, is connected to the cam 4.
3 and when the cam 43 rotates clockwise from the illustrated position, the operating lever 45 is pushed to the left, and at this time, the projection 45C formed on the operating lever 45 pushes the shutter blade closing ring 34 protruding arm 3 formed in
4C is pushed by the protruding arm 45C to rotate the shutter blade closing ring 34 counterclockwise against the action of the spring 36 to a position where the shutter blade can be opened and closed.

Also, it is pivoted by a shaft 46, and a pin (or elongated hole) 47a provided at the upper end is connected to an elongated hole (or elongated hole) provided at the left end of the operating lever 45.
The bent portion 475 at the lower end of the second actuating lever 47, which is slidably engaged with the locking lever 45cl, is positioned opposite to the left edge of the upper end of the locking lever 38.

Therefore, the cam 43 is rotated clockwise by the set motor 42, the operating lever 45 is pushed to the left, and the shutter blade closing ring 34 is rotated counterclockwise to the position where the shutter blades can be opened and closed. The actuating lever 47 is rotated counterclockwise by the engagement between the pin 47α and the elongated hole 45d, and the locking lever 38 is rotated clockwise by the bent portion 47b against the action of the spring 39. The locking shoulder 34b of the shutter blade closing ring 34 located directly below the locking shoulder 38α is locked, and in this state, the magnetic piece 40 is attracted by the magnet 41, and the locking lever 38 is moved to the shutter blade closing ring 34. Hold in locked position. As described above, when the recoil 29 that closes the shutter blade is attached, the magnetic force of the magnet 41 is weakened, and the attraction of the magnetic piece 40 is released by the action of the spring 39, and the locking lever 38 is released. The locking action is released and the shutter blade closing ring 34 is moved to the fully closed position of the shutter blade 35.

The operation of the device according to the present invention, which is configured as a double series, is as follows. When the device is used as a movie camera, the first selector switch 10 is connected to the contact α. As a result, the output from the image sensor 5 is inverted via the inverter 9 and given to the servo automatic aperture circuit 13 via the switch IO, but when the field brightness is high and the output of the image sensor 5 is at a high level, the inverter 9 The inverted low-level field brightness information signal is input to close the shutter blade, and when the field brightness is low, the shutter blade opens and adjusts the shutter blade aperture according to the field brightness. work to maintain

When using this device as a still camera, the first changeover switch 10 is switched to the contact position. Since the second changeover switch 20 always maintains the connection point C at a low voltage level, the output of this low voltage level is given to the servo automatic diaphragm circuit 13 via the changeover switch IO, and therefore the drive motor 11 controls the shutter blades. continues to operate in the closing direction to bring the shutter blades into a fully closed state, clearing the still image recording section 30 and making it ready for recording the next still image. At the same time, since the low voltage level of the connection point C is applied to the base of the transistor 22, the transistor 22 becomes conductive and short-circuits the capacitor 23.

The aperture shutter mechanism 3 is the second one for capturing still images.
When the shutter release is performed in the state shown in the figure, the changeover switch 20 is switched to be connected to the power supply voltage Vcc, and the connection point C is set to a high voltage level. is the servo automatic aperture circuit 13
The shutter blades are gradually opened by the drive motor 11 while being braked by the brake coil 14. At the same time, this high voltage level
is also applied to the base of the transistor 22 to make it non-conductive and start charging the capacitor 23. At this time, one end d of the capacitor 23 is connected to the charge current amplifier 19 connected to the light receiving element 18. Therefore, it is charged by the current Ip according to the field brightness, and after a time corresponding to the field brightness, it becomes equal to the reference voltage at the connection point C, and the comparator 24 is inverted, and the single pulse generating circuit 27
is activated, and its output pulse causes transistor 2 to be activated.
8 is made conductive and the shutter blade closing actuating coil 29 is biased by μf. Therefore, while the locking action of the locking lever 38 is released and the shutter blade continues to open, the shutter blade closing ring 34 is activated by the spring. 36, the shutter blades are rapidly moved to the fully closed position to close the shutter blades and provide proper exposure. As a result, the shutter blades are closed once and the still image circuit is cleared, and then the shutter blades are opened and closed for an appropriate exposure time depending on the field brightness, and the image voltage distribution on the image sensor accumulated during that time is recorded as a video. A still image can be obtained by reading it out as a signal and inputting it to the still image recording section 30.

After a delay time by the delay circuit 31 after recording the still image, the set motor drive circuit 32 is energized and the set motor 42 is operated, and the operating lever 45.47 is activated as described above.
Through this, the shutter blade closing ring 34 is rotated to a position where the shutter blades can be opened and closed, and is locked in that position by a locking lever 38.

According to the present invention, by using a common servo automatic aperture circuit, it can be used as a movie camera or a still camera, and when recording still images, the shutter blade can be closed to obtain proper exposure. A dedicated shutter blade closing ring, which is provided separately from the shutter blade opening/closing ring, can be used instantly while the shutter blades are opening, eliminating the need to rapidly reverse the inertial forces of the drive motor, etc. Therefore, it is possible to obtain the advantage that the operating precision is improved.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram showing the general structure and control circuit of a still camera/movie camera incorporating the present invention. FIG. 2 is an explanatory diagram showing an aperture shutter mechanism according to the present invention. 3... Aperture shutter mechanism 5... Imaging device 6... Image intensifier 10.20... Changeover switch 11... Drive Motor 12... Differential amplifier 13... Servo automatic throttle circuit 14...
- Braking coil 15... Arithmetic amplifier 18... Light receiving element 19... Photocurrent amplifier 22.28... Transistor 23...・
・ Integrating capacitor 24... Comparator ・ 25.26... Voltage dividing resistor 27... Single pulse generating circuit 29... Sha, Tsuta-blade closing actuating coil 3
0...Style image recording section 31...
Delay circuit 32... Set motor drive circuit 33...
.../Yatsuter blade opening/closing ring 34... Shutter blade closing ring 35... Shutter blades 36, 39... Spring 38... Locking lever 40... ... Magnetic piece 41 ... Permanent magnet 42 ... Mountain Set motor 43 ... Cam 45.47 ... Actuation lever patent applicant Copa Louis Co., Ltd.

Claims (2)

[Claims] (1) The shutter is opened and closed by a shutter blade opening/closing ring connected to the drive motor and operated by the energization of the drive motor, and the shutter is operated by the shutter blade closing ring which cooperates with the shutter blade closing actuation coil and is operated by the energization of the shutter blade closing ring. An electromagnetically driven aperture shutter mechanism with shutter blades that also functions as an aperture that is fully closed regardless of the operation of the blade opening/closing ring, an image sensor that receives field light through this aperture shutter mechanism, and an image sensor that is connected to the image sensor. It includes a stale image recording unit and the drive motor, and operates to compare a given information voltage with a reference voltage, close the shutter blade when the given information voltage is lower than the reference voltage, and open the shutter blade when it is higher. and a servo automatic aperture circuit that maintains the shutter blade at the shutter blade aperture position at that time when the voltage difference between the two becomes zero, and a servo automatic aperture circuit that maintains the shutter blade at the current shutter blade aperture position, and a low voltage level output of the image sensor output when the field brightness is high. a first changeover switch having a first contact selectively connected to said servo automatic throttle circuit through a generating circuit; and a second contact of said first changeover switch connected to said first changeover switch and normally at a low voltage level a second changeover switch that is switched to a high voltage level in conjunction with the shutter release; a light receiving element that receives field light and generates a field brightness information signal; connected to the second changeover switch, and when the second changeover switch is at a low voltage level with the first changeover switch being switched to a second contact, the shutter blade is closed by the servo automatic diaphragm circuit; When the voltage level is switched to a high voltage level, the shutter blade is opened and the field brightness information signal of the light-receiving element is inputted, and after a period of time corresponding to the field brightness has elapsed, the pulse generating circuit is activated to close the shutter. The camera is characterized by comprising a time-fixing circuit that energizes a blade drive coil to close the shutter blade and provides appropriate exposure according to field brightness so that the still image recording section obtains a still image. Servo automatic aperture device with shutter function. (2) The shutter blade closing ring is urged to the shutter blade fully closed position by the first spring, and the shutter blade is opened and closed by the locking lever against the action of the first spring. The locking lever is attracted by a second spring and a magnet that act to bias the locking lever to a position where the shutter blade closing ring is released. A magnetic piece is provided that locks the shutter blade closing ring in a position where the shutter blades can be opened and closed against the action of the second spring, and the shutter blade closing actuation coil cooperates with the magnet to When the magnet is biased, the magnetic force of the magnet is weakened to release the magnetic piece, and the locking lever is biased to a position where the locking is released by the action of the second spring. operatively connected to a set motor, when the set motor is energized, the shutter blade closing ring is pushed against the action of the first spring to a position where the shutter blades can be opened and closed; an actuating lever device operatively connected to the shutter blade closing ring and the locking lever for pushing the locking lever to lock the closing ring in a position in which the shutter blades can be opened and closed;
A set motor energizing circuit is connected to the time-fixing circuit via a delay circuit, so that when the first switching lever is switched to the second contact, the second switching lever is switched to the second switching lever. After the shutter blade is switched to a high voltage level in conjunction with the shutter release and the shutter blade is opened and closed by the timing circuit, after a predetermined delay time has elapsed by the delay circuit, the focus motor is energized and the locking lever is activated to open and close the shutter blade. A servo automatic diaphragm device having a shutter function according to claim 1, wherein the closing ring is locked in a position where the shutter blades can be opened and closed.