JP4030657B2 - Electronic camera shutter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shutter of an electronic camera.
[0002]
[Prior art]
When taking an image with an electronic camera, unlike a camera that takes an image on a film, it is not performed by mechanically opening and closing the shutter, but it is exposed by turning on the power of the CCD, which is a solid-state image sensor. When the exposure amount is obtained, the power is turned off to stop the exposure. However, if the exposure is stopped by turning off the power supply, it is difficult to set the exposure amount precisely. Therefore, when stopping the exposure, the shutter is mechanically closed and the exposure is stopped instantaneously. Thus, the power of the CCD is turned off.
[0003]
As a conventional mechanism for that purpose, for example, in the one disclosed in Japanese Utility Model Publication No. 4-31128, two shutter members are provided so as to be relatively slidable in a positional relationship such that a part thereof overlaps. A shutter opening is provided at this overlapping position. At one sliding position, both shutter openings overlap to open the opening, and at the other sliding position, both shutter openings are shifted and the opening is closed. Normally, the opening is held at a position where the opening is opened, and when a predetermined exposure amount is obtained, the shutter member is slid to shift the opening and stop the exposure instantaneously.
[0004]
[Problems to be solved by the invention]
However, in such a conventional configuration, the opening amount of the shutter opening cannot be adjusted. Therefore, for the diaphragm, diaphragm blades, a control member for adjusting the diaphragm, and driving means thereof are separately required. As a result, the configuration becomes complicated and the cost increases accordingly.
[0005]
[Means for Solving the Problems]
In order to solve the above problems, the present invention controls a sector that opens and closes a shutter opening by a control member that adjusts and closes the opening amount of the shutter opening. This control member is composed of an aperture cam and a sector lever. When a desired aperture cam surface is selected by the sector lever, the sector is driven to adjust the opening amount of the shutter opening, and the image sensor is energized for exposure. Starting, when the valley surface of the diaphragm cam is selected by the sector lever, the sector is driven to close the shutter opening and stop the exposure of the image sensor. Further, according to the present invention, the diaphragm sector is controlled by the diaphragm control member, the closure sector is controlled by the closure control member, and both control members are driven by one drive source. By using such a sector and a control member, it is possible to control and close the shutter opening with a simple configuration.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The shutter of the electronic camera of the present invention includes an image sensor that can be exposed by energization, a sector that opens and closes the shutter opening, and a control member that adjusts and closes the opening of the shutter opening. The sector is normally held at the open position and is applied with a biasing force in the direction of closing the shutter opening, and the control member has alternating cam surfaces for setting different apertures on the outer periphery and trough surfaces for closing the openings. And a sector lever that adjusts and closes the opening amount of the shutter opening by driving the sector in conjunction with the cam surface and the valley surface. The imaging device starts exposure of the subject image by energization when a desired cam surface of the aperture cam is selected, and the shutter opening is closed when the valley surface following the selected cam surface is reached. To stop the exposure.
[0007]
Furthermore, the shutter of the electronic camera of the present invention adjusts the image sensor that can be exposed by energization, the sector for the aperture that sets the aperture of the shutter opening, the sector for closing that closes the shutter aperture, and the aperture of the shutter aperture. And a control member for closing the shutter opening. The diaphragm sector and the closing sector are normally held in the open position and are given a biasing force in the direction of closing the shutter opening, and the control member for adjusting the diaphragm is a cam surface that sets a different diaphragm on the outer periphery. And an aperture sector lever that adjusts the aperture of the shutter opening by driving the aperture sector in conjunction with the cam surface. In addition, the closing control member closes the shutter opening by driving a closing sector in conjunction with the closing cam formed with one cam surface and a valley surface closing the opening on the outer periphery, and interlocking with the valley surface. It consists of a sector lever for closing. Both control members are driven by a single drive source, and the imaging device starts exposure of the subject image by energization when a desired diaphragm cam surface of the diaphragm cam is selected, and the closing cam When the trough surface is reached, the shutter opening is closed and exposure is stopped.
Furthermore, it is preferable that the aperture cam or the closing cam is driven by a one-way rotating motor.
[0008]
【Example】
The embodiment will be described with reference to the drawings. In FIG. 1, a gear 3 is meshed with a drive wheel 2 fixed to a motor shaft 1 of a drive motor (not shown) provided on a substrate (not shown). This drive motor is a step motor and is controlled to rotate in one direction. In this example, the drive wheel 2 is driven to rotate in the clockwise direction, and therefore the gear 3 is driven to rotate in the counterclockwise direction.
The gear 3 is provided with a concentric aperture cam 4 that rotates integrally. The aperture cam 4 is provided with first, second, third and fourth cam surfaces 4a, 4b, 4c and 4d having different diameters in order for setting the aperture of the four-stage shutter opening 8 on the outer periphery. There is a paragraph that falls from the rear end of each of the cam surfaces 4a to 4d to the valley surface 4e that closes the shutter opening 8.
[0009]
The sector lever 5 is swingably supported around a shaft 5a, and is provided with a protrusion 5b at one end and a sector drive pin 5c at the other end. One end of a spring 5d is hooked to the sector lever 5, and the other end of the spring 5d is hooked to a fixing member (not shown), for example, a substrate on which a motor is provided. As a result, the spring 5d biases the protrusion 5b in a direction in which the protrusion 5b is brought into elastic contact with the aperture cam 4.
A pair of sectors 6 and 7 are disposed so as to be swingable about the shafts 6a and 7a. Sectors 6 and 7 are arranged to be partially overlapped, and long grooves 6b and 7b into which the drive pins 5c are fitted are provided on the base side where the shafts 6a and 7a are located. The front end of the sector is substantially C-shaped, and the opening amount of the shutter opening 8 is adjusted by the inner sides 6c and 7c. The sectors 6 and 7 cover the opening 8 and close the shutter opening 8 as shown in FIG. To do.
[0010]
Next, the operation will be described with reference to the time chart of FIG. In the state shown in FIG. 1, the protrusion 5b is in elastic contact with the first cam surface 4a, the sector lever 5 is swung clockwise against the spring 5d, and the sector drive pin 5c is retracted from the shutter opening 8. The sectors 6 and 7 are in a fully open state in which the front end portion is opened and the shutter opening 8 is opened from the inner sides 6c and 7c. One rotation of the diaphragm cam 4 is configured as one continuous operation when setting the diaphragm.
As shown in FIGS. 1 and 3, at the position where the projection 5b is in elastic contact with the first cam surface 4a, the motor shaft 1 is rotated and the gear 3 is rotated via the driving wheel 2, so that the aperture cam 4 is rotated counterclockwise. When rotating, the projection 5b falls on the valley surface 4e, the sector lever 5 advances the sector drive pin 5c toward the shutter opening 8 side by the spring 5d, and the sectors 6 and 7 are swung as shown in FIG. Close.
[0011]
The gear 3 is continuously driven to rotate, and the diaphragm cam 4 is also rotated. This time, the protrusion 5b comes into a position where it comes into elastic contact with the second cam surface 4b. Since the cam surface 4b is lower than the cam surface 4a, the sector drive pin 5c is slightly in the forward position, and the inner sides 6c and 7c of the sector are located slightly closer to the center. Slightly less, it will be in the aperture state. However, when this aperture state is still insufficient, the CCD is still left off.
The gear 3 is continuously driven to rotate, so that the diaphragm cam 4 is also rotated. Similarly to the above, the protrusion 5b once falls on the valley surface 5e and then comes into a position where it comes into elastic contact with the third cam surface 4c. The aperture is further reduced in amount. When this aperture state is a desirable aperture, the CCD power supply is turned on as shown in FIG.
[0012]
Since the movements of the sectors 6 and 7 are determined in advance by the shape of the diaphragm cam 4, the timing for turning on the power supply of the CCD appropriately changes depending on the desired exposure amount. In the present embodiment, the power of the CCD is turned on at the timing shown in FIG. 3. However, when more exposure is required than in this embodiment, the power is turned on at an earlier timing than the timing shown in FIG. When it is necessary to further reduce the exposure amount, the power is turned on at a timing later than the timing shown in FIG.
When an appropriate exposure amount is obtained, the protrusion 5b passes through the cam surface 4c and falls to the valley surface 4e, and the sector lever 5 advances the sector drive pin 5c toward the shutter opening 8 by the spring 5d as shown in FIG. Then, the sectors 6 and 7 are swung to close the shutter opening 8 to stop the exposure of the image sensor. Thereafter, the power of the CCD is turned off as shown in FIG.
[0013]
The gear 3 is continuously driven to rotate, and the protrusion 5b is brought into elastic contact with the fourth cam surface 4d to make the sectors 6 and 7 in a further reduced state. At this time, since the CCD is off, exposure is no longer performed. When the projection 5b falls again on the valley surface 4e to close the shutter opening, and the projection 5b comes to a position where it comes into elastic contact with the first cam surface 4a again, one operation for photographing is finished.
If the desired aperture is selected and the power of the CCD is turned on during one continuous operation for setting the aperture in this way, the shutter opening 8 is set to sectors 6 and 7 when a predetermined exposure amount is obtained. Then, the power of the CCD is turned off to stop the exposure, and the imaging is completed.
[0014]
FIG. 4 shows another embodiment, in which a pair of sectors 16 and 17 for diaphragm and a pair of sectors 26 and 27 for closing are opposed to each other across the shutter opening 18. It is. This is because the shape of the inner side of the sector that achieves the function most desirably differs between the throttle and the closure, so that the transmission system is branched separately from the common drive source and configured separately. This sector is provided separately.
That is, the drive wheel 12 is provided on the motor shaft 11 as described above, and the gear 13 and the gear 23 are separately engaged with the drive wheel 12. The gear 13b is engaged with the gear 13 through the pinion 13a. An aperture cam 14 that rotates integrally is provided concentrically on the gear 13b. The aperture cam 14 is provided with first, second, third and fourth cam surfaces 14a, 14b, 14c and 14d for setting four stages of apertures on the outer circumference, with different diameters in order. The rear end of the surface continues to the front end of the next cam surface by an inclined surface.
[0015]
The sector lever 15 is supported so as to be swingable about a shaft 15a, and has a projection 15b at one end and a sector drive pin 15c at the other end. One end of a spring 15d is hooked to the sector lever 15, and the other end of the spring 15d is hooked to a fixing member (not shown), for example, a substrate on which a motor is provided, like the spring 5. As a result, the spring 15d biases the protrusion 15b in a direction in which the protrusion 15b is brought into elastic contact with the aperture cam 14.
A pair of diaphragm sectors 16 and 17 are arranged so as to be swingable about shafts 16a and 17a. The shapes of the sectors 16 and 17 are the same as described above, and the opening amount of the shutter opening 8 is adjusted by the long grooves 16b and 17b into which the driving pin 15c is fitted on the base side and the inner sides 16c and 17c on the tip side. The inner sides 16c and 17c are provided with cutout portions 16d and 17d so as to show one sector 16 in FIG. This is to ensure that different aperture states are performed as evenly as possible.
[0016]
A pair of sectors 26 and 27 for closing are disposed at positions symmetrical to the sectors 16 and 17 with respect to the shutter opening 18. As a configuration for driving the sectors 26 and 27, a closing cam 24 that rotates integrally with the gear 23 is provided concentrically. The closing cam 24 has one cam surface 24a on the outer periphery, the rear end portion of the cam surface falls into the trough surface 24b, and the inclined surface is continuous from the trough surface 24b to the front end portion of the cam surface 24a. ing.
The sector lever 25 is supported so as to be swingable about a shaft 25a, and is provided with a projection 25b at one end and a sector drive pin 25c at the other end. One end of a spring 25d is hooked to the sector lever 25, and the other end of the spring 25d is hooked to a fixing member (not shown), for example, a board on which a motor is provided. As a result, the spring 25d biases the protrusion 25b in a direction in which the protrusion 25b is brought into elastic contact with the closing cam 24.
[0017]
Sectors 26 and 27 are disposed so as to be swingable about shafts 26a and 27a. The shapes of the sectors 26 and 27 are substantially the same as described above, and long grooves 26b and 27b into which the drive pins 25c are fitted are provided on the base side. The leading end of the sector is substantially C-shaped, and the shutter opening 18 is closed by the sectors 26 and 27. In this sector, as shown in one sector 26 in FIG. 5B, the inner side 26c has an arc shape and is not provided with a notch. This is because it takes time to close the opening 18 if there is a notch. Since it is desired to close the shutter in as short a time as possible, the shutter is shaped so as not to have a notch.
The rotational speeds of the aperture cam 14 and the closing cam 24 interlocked with the drive wheel 12 are set to 1: 4 by the reduction gear train via the pinion 13a and the gear 13b. That is, the closing cam 24 rotates four times for one rotation of the aperture cam 14, in other words, the cam surface 24a and the valley surface 24b of the closing cam 24 correspond to each of the four cam surfaces 14a to 14d of the aperture cam 14. ing.
[0018]
The operation of this embodiment will be described. First, the motor shaft 11 rotates clockwise, and the gear 13 and the gear 23 rotate via the drive wheel 12. When the gear 13b rotates via the pinion 13a in conjunction with the rotation of the gear 13, the aperture cam 14 starts to rotate clockwise. At the same time, the closing cam 24 starts to rotate counterclockwise in conjunction with the rotation of the gear 23. Therefore, when the projection 15b is disengaged from the rear end portion of the first cam surface 14a of the aperture cam 14, the projection 25b falls from the rear end portion of the cam surface 24a of the closing cam 24 to the valley surface 24b. Therefore, the sector lever 25 moves the sector drive pin 25c forward to the shutter opening 18 side by the spring 25d, swings the sectors 26 and 27, and closes the shutter opening 18.
[0019]
The rotation of the drive wheel 12 continues, and the protrusion 15b slides on the outer periphery of the aperture cam 14 and comes into a position where it elastically contacts the second cam surface 14b. Since the cam surface 14b is lower than the cam surface 14a, the sector drive pin 15c is positioned slightly forward, and the inner sides 16c and 17c of the sector are located slightly closer to the center. The aperture is slightly reduced. However, in this state, when the aperture is still insufficient, the CCD is still left off. At this time, since the closing cam 24 rotates once and the protrusion 25b is in sliding contact with the cam surface 24a from the valley surface 24b, if the rotation of the driving wheel 12 continues further, it will fall again to the valley surface 24b. Similarly, the shutter opening 18 is closed again by the sectors 26 and 27.
[0020]
Then, the drive wheel 12 continues to rotate, and the protrusion 15b slides on the outer periphery of the aperture cam 14 and comes to a position where it comes into elastic contact with the third cam surface 14c. Since the cam surface 14c is lower than the cam surface 14b, the sector drive pin 15c is further advanced and positioned, and the inner sides 16c and 17c of the sector are positioned closer to the center. Therefore, the opening amount of the shutter opening 18 is further increased. The aperture is reduced. When this is the desired aperture state, the CCD power supply is turned on at a desired timing, and exposure to the image sensor is started. At this time, the closing cam 24 is further rotated once and the projection 25b is again in contact with the cam surface 24a. Therefore, when an appropriate exposure amount is obtained, the projection 25b falls on the valley surface 24b and is the same as described above. Thus, the shutter opening 18 is closed by the sectors 26 and 27, and the exposure of the image sensor is stopped here. Then, as shown in FIG. 2, the CCD is turned off.
[0021]
The gears 13 and 23 are continuously driven to rotate, and the projection 15b is brought into elastic contact with the fourth cam surface 14d to make the sectors 16 and 17 have a smaller aperture state. At this time, since the CCD is off, exposure is no longer performed. Further, the closing cam 24 rotates once to close the shutter opening 18 in the same manner as described above, and the projections 15b elastically contact the cam surface 14a and the projections 25b elastically contact the cam surface 24a by the subsequent rotation of the gears 13 and 23. When it comes to, one operation for photographing is finished.
In this embodiment, the height of the cam surface is set to four levels. However, this is not limited to four levels, and is designed to correspond to the required number of aperture settings. Further, the blade is driven by the lever, but may be driven via a ring-shaped member. Further, the motor is not limited to the step motor, and other types of motors such as a DC motor and an ultrasonic motor can be used.
[0022]
【The invention's effect】
According to the present invention, the opening amount of the shutter opening is controlled by the sector, that is, the aperture is controlled, and the shutter opening is closed by the same sector, so that the aperture of the shutter opening and the necessary exposure amount can be obtained with a simple configuration. The exposure can be stopped by closing the shutter opening at that time. Further, by providing a shutter blade and a diaphragm blade separately, it is possible to obtain a more appropriate blade shape and improve exposure performance. Further, since it can be driven by a one-way rotary motor, an electronic camera can be provided at low cost without requiring complicated control.
[Brief description of the drawings]
FIG. 1 is a plan view showing a fully open state of a shutter opening.
FIG. 2 is a plan view showing a closed state of a shutter opening.
FIG. 3 is a time chart showing an imaging operation.
FIG. 4 is a plan view showing a fully opened state of a shutter opening in another embodiment.
5 (a) is a plan view of the aperture sector of FIG. 4, and FIG. 5 (b) is a plan view of the closure sector of FIG.
[Explanation of symbols]
4 Aperture cams 4a to 4d Cam surface 4e Valley surface 5 Sector levers 6, 7 Sector 12 Drive source (drive vehicle)
14 Aperture cams 14a to 14d Cam surface 15 Sector levers 16 and 17 for aperture 18 Sectors for aperture 18 Shutter opening 24 Closure cam 24a Cam surface 24b Valley surface 25 Sector levers 26 and 27 for closure

Claims (3)

An image sensor that can be exposed by energization, a sector that opens and closes a shutter opening, and a control member that adjusts and closes the opening of the shutter opening;
The sector is normally held in an open position, and a biasing force is applied in a direction to close the shutter opening,
The control member is configured to drive the sector in conjunction with an aperture cam in which cam surfaces for setting different apertures on an outer periphery and a valley surface for closing an opening are alternately formed, and the cam surface and the valley surface. A sector lever for adjusting and closing the opening amount of the shutter opening,
The imaging device starts exposure of the subject image by energization when a desired cam surface of the aperture cam is selected, and the shutter opening is closed when the valley surface following the selected cam surface is reached. And stopping the exposure, the shutter of the electronic camera. An imaging device that can be exposed by energization, an aperture sector that sets an aperture of a shutter aperture, a closing sector that closes the shutter aperture, a control member that adjusts the aperture of the shutter aperture, and the shutter aperture A control member for closing,
The squeezing and closing sectors are normally held in an open position, and a biasing force is applied in a direction to close the shutter opening,
The control member for adjusting the aperture includes an aperture cam having a cam surface for setting different apertures on the outer periphery, and driving the aperture sector in conjunction with the cam surface to control the aperture amount of the shutter opening. It consists of a sector lever for adjusting the aperture,
The closing control member includes a closing cam in which one cam surface and a valley surface closing the opening are formed on an outer periphery, and driving the closing sector in conjunction with the valley surface to drive the shutter opening. It consists of a sector lever for closing,
Both the control members are driven by one drive source,
When the diaphragm sector lever is in contact with the cam surface for setting the diaphragm, the closing sector lever is in contact with the cam surface of the closure cam,
When the aperture sector lever is released from the cam surface for setting the aperture, the closing sector lever falls on the valley surface of the closure cam,
The imaging device starts exposure of the subject image by energization when the cam surface of the desired aperture of the diaphragm cam is selected by said diaphragm sector lever valley surface of the sector lever for the closure the closure cams A shutter for an electronic camera, wherein the shutter opening is closed to stop the exposure when the camera reaches the shutter. 3. The shutter of the electronic camera according to claim 1, wherein the aperture cam or the closing cam is driven by a one-way rotation motor.

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