JP6871693B2 - Blade drive device, focal plane shutter device, and image pickup device - Google Patents

Description

The present invention relates to a blade driving device for moving blades in and out of a path through which light passes, a focal plane shutter device provided with the blade driving device, and an imaging device provided with the blade driving device or the focal plane shutter device.

As a blade driving device, a shutter device such as a focal plane shutter device that allows a plurality of blades to enter and exit the light passage path is known (see Patent Document 1). By the way, since such a shutter device is mounted on an image pickup device such as a camera, further evolution is required with the miniaturization and higher functionality of the image pickup device.

Japanese Unexamined Patent Publication No. 2003-315872

In the shutter device of Patent Document 1, it is described that the drive member that drives the front blade and the rear blade comes into contact with the buffer member and stops when the operation is stopped. If the cushioning member is attached so as not to come off even after repeated operations, there is a risk of interference when driving the blades and the driving member.

The present invention provides a blade drive device, a focal plane shutter device, and an image pickup device that can reduce an impact in the operation of a drive pin with a simple configuration that does not interfere with the operation of the blades.

The blade drive device of the present invention
An opening forming member that forms an opening,
A cover member that forms a blade chamber between the opening forming member and
A group of blades that open and close the opening,
Two arms that rotatably connect and support the blade group,
It has a drive pin connected to the arm, and the drive pin is inserted into a hole provided in the cover member and rotates in parallel with the opening surface of the opening to open and close the blade group. Drive member and
A cushioning member attached on an extension of the rotation locus of the driving member in the hole and formed of a resin material, and a cushioning member.
An elastic member provided between the cushioning member and the inner wall of the hole on the extension of the rotation locus of the driving member and having elasticity more than the cushioning member is provided.
The cushioning member has at least one convex portion and a concave portion, and has at least one convex portion and a concave portion.
The convex portion is in contact with the cover member side recess provided in the cover member, the recess that makes contact with the cover member side protrusion provided on said cover member, said elastic member and contact with said bore It is attached to the part ,
The drive member is characterized in that the drive pin is held in contact with the cushioning member in a standby state.

According to the present invention, it is possible to provide a cushioning member that does not interfere with the operation of the blades.

The block diagram which shows the whole structure of the image pickup apparatus which concerns on one Embodiment of this invention. An exploded perspective view of a focal plane shutter according to an embodiment of the present invention as viewed from the rear side. An exploded perspective view of a focal plane shutter according to an embodiment of the present invention as viewed from the front side. The figure which enlarged a part of the focal plane shutter which concerns on one Embodiment of this invention. FIG. 3 is a cross-sectional view of a focal plane shutter according to an embodiment of the present invention. An enlarged view of a main part of a focal plane shutter according to an embodiment of the present invention. The perspective view for demonstrating how to attach the cushioning member of the focal plane shutter which concerns on one Embodiment of this invention. An enlarged view of a blade driving member 202 of a focal plane shutter according to an embodiment of the present invention. An exploded perspective view of a blade driving member 202 of a focal plane shutter according to an embodiment of the present invention. The view which saw the electromagnet of the focal plane shutter which concerns on one Embodiment of this invention from the mounting direction to the auxiliary main plate. The figure which looked at the cam gear of the focal plane shutter which concerns on one Embodiment of this invention from the front. An exploded perspective view of a charge cam portion of a focal plane shutter according to an embodiment of the present invention. It is an exploded perspective view around the motor of the focal plane shutter which concerns on one Embodiment of this invention. It is a figure which looked at the focal plane shutter which concerns on one Embodiment of this invention from the front, and is the figure which shows the overcharge state of a vane drive member. It is an excerpt figure (initial) which shows the overcharge state before running of the focal plane shutter blade group which concerns on one Embodiment of this invention. It is an excerpt figure (set release) which shows the standby state before running of the focal plane shutter blade group which concerns on one Embodiment of this invention. It is an excerpt drawing which shows the exposure control operation middle of the focal plane shutter blade group which concerns on one Embodiment of this invention (in the middle of the rear curtain running). It is an excerpt drawing which shows the traveling completion state of the focal plane shutter blade group which concerns on one Embodiment of this invention (rear curtain traveling completion bound lock). It is an excerpt figure (unlocking) which shows the lock release start state before the charge start of the focal plane shutter blade group which concerns on one Embodiment of this invention. It is an excerpt figure which shows the light-shielding curtain charge start state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain charge start). It is an excerpt figure which shows the light-shielding curtain charge middle state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain charge middle). It is an excerpt figure which shows the light-shielding curtain charge aperture arrival state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain aperture arrival). It is an excerpt figure which shows the light-shielding curtain charge MAX state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain MAX charge). It is an excerpt figure which shows the light-shielding curtain swing state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain swing). It is an excerpt figure which shows the light-shielding curtain overcharge state of the focal plane shutter blade group which concerns on one Embodiment of this invention (light-shielding curtain overcharge). FIG. 6 is an excerpt (holding of a light-shielding curtain) showing a state before opening the light-shielding curtain of a focal plane shutter blade group according to an embodiment of the present invention. An enlarged view of the periphery of the charge cam of the focal plane shutter according to the embodiment of the present invention (when traveling is completed). An enlarged view (unlocking) around the charge cam of the focal plane shutter according to the embodiment of the present invention. An enlarged view (shaking curtain swing) around the charge cam of the focal plane shutter according to the embodiment of the present invention. An enlarged view (holding a light-shielding curtain) around a charge cam of a focal plane shutter according to an embodiment of the present invention. The figure which shows the operation timing of the focal plane shutter and the image pickup element which concerns on one Embodiment of this invention. The figure which shows the operation timing of a conventional focal plane shutter and an image sensor. The figure which shows the power transmission structure of the focal plane shutter which concerns on one Embodiment of this invention.

Hereinafter, the present invention will be described in detail based on one embodiment.

FIG. 1 is a diagram showing the overall configuration of the image pickup apparatus 100 according to the present embodiment.

An image pickup element 2 for photoelectrically converting a subject image imaged by the image pickup lens 1 is provided on an extension in the optical axis direction of the image pickup lens 1 for forming an image of light from a subject. A CMOS image sensor is used as an example of the image sensor 2.

The focal plane shutter 3 is provided between the image pickup lens 1 and the image pickup element 2 on the photographing optical path, and adjusts the time for exposing the image pickup element 2 in conjunction with the electronic front curtain operation of the image pickup element 2 described later. Then, the analog image signal output from the image sensor 2 is converted into a digital signal by the AFE4.

The DSP (Digital Signal Processor) 5 performs various image processing, compression / decompression processing, and the like on the digital image signal output from the AFE4. The image data obtained as a result is stored in the recording medium 6. The captured image, various menu screens, and the like are displayed on the display unit 7. A liquid crystal display (LCD) or the like is used as the display unit 7.

The timing generator (TG) 8 supplies a drive signal to the image sensor 2. The CPU 9 controls the AFE4, the DSP5, the TG8, and the shutter drive circuit 11. Image data and the like are temporarily stored in the RAM 10 connected to the DSP 5.

Further, the shutter drive circuit 11 drives the focal plane shutter 3 according to the control by the CPU 9.

A voltage detecting means 91 for detecting the power supply voltage of the imaging device, a temperature detecting means 92 for detecting the temperature of the imaging device, and a blade detecting means 93 provided inside the focal plane shutter 3 are provided. It is composed of a photo sensor 217b and a cam phase plate 208, which will be described later. A cam phase detecting means 95 is provided inside the focal plane shutter 3. The detection result of each detection means is input to the CPU 9.

The lens control means 94 outputs lens information such as the focal length, aperture diameter, pupil diameter, and distance between the pupil and the image sensor 2 of the image pickup lens 1 to the CPU 9, and drives the aperture and the lens according to the control by the CPU 9.

Hereinafter, the focal plane shutter according to the embodiment of the present invention will be described with reference to the exploded perspective view and the enlarged perspective view of the main part shown in FIGS. 2 to 13 and the shutter operation state diagram shown in FIGS. 14 to 26, respectively. ..

FIG. 2 is an exploded perspective view of the focal plane shutter 3 of the camera according to the embodiment of the present invention as viewed from the back surface, and FIG. 3 is an exploded perspective view seen from the front surface.

The shutter base plate 201 is an example of an opening forming member that forms an opening through which light passes, and is fixed to a camera body (not shown) to which each component constituting a drive mechanism of the rear blade group 230, which will be described later, is attached. .. In the following description, exposure control by so-called electronic front curtain control will be described as a drive source release of the camera according to the embodiment of the present invention. Among them, for convenience of explanation, those expressed as a rear blade group or a rear blade are preferably read as an exposure control blade group or an exposure control blade in consideration of their functions. That is, the only blades that travel in the exposure control are the exposure control blades (rear blades), and the expressions "front" and "rear" do not strictly express their functions, but in consideration of the comparison with the conventional driving method, the rear blades And the expression "afterglow" is sometimes used.

The blade driving member 202 is rotatably supported by the shaft 201a of the shutter base plate 201. The blade driving member 202 is provided with an armature support portion 202d.

The through hole portion (not shown) formed in the armature support portion 202d has a flange larger than the inner diameter of the through hole portion, and the armature shaft 213 integrally attached to the armature 212 is engaged. (See FIGS. 8 and 9). The armature shaft 213 extends in a direction substantially orthogonal to the suction surface of the armature 212.

A compression spring 214 is arranged on the outer periphery of the armature shaft 213 between the armature 212 and the armature support portion 202d, and urges the armature 212 and the armature support portion 202d in a direction to separate them from each other.

Returning to FIG. 2, the ratchet 240 is rotatably supported around the shafts 201a and 201b of the shutter base plate 201, and is arranged on the shaft tip side of the blade driving member 202.

A blade drive spring 241 and a light-shielding blade drive spring 341, which are torsion coil springs, are arranged between the blade drive member 202, the light-shielding blade drive member 302, and the ratchet 240.

One end of the blade drive spring 241 and the light-shielding blade drive spring 341 is hung on the blade drive member 202 and the light-shielding blade drive member 302, respectively, and the other end is hung on the ratchet 240.

The blade drive spring 241 and the light-shielding blade drive spring 341 give a clockwise urging force to the blade drive member 202 and the light-shielding blade drive member 302, respectively, when viewed from the shaft tip side (right side in FIG. 2) in FIG.

The blade group 230 is composed of the first blade 231, the second blade 232, the third blade 233, the main arm 235, and the sub arm 236. The light-shielding blade group 330 has the same configuration as the blade group 230 and is used by turning over the arrangement.

The 1st blade 231 and the 2nd blade 232 and the 3rd blade 233 are made of a resin sheet (or metal plate) coated with black paint, and are rotatably supported by the main arm 235 and the sub arm 236, and are parallel links. Is forming.

The first blade 231 of the blade group 230 is an exposure control blade, its end side 231a is a slit forming portion for controlling exposure, and the end face of the slit forming portion for controlling exposure is laser-machined for local burrs such as a press. The amount of protrusion from the peripheral end face is suppressed to 20 μm or less, and the end face is made uniform.

The second blade 232 and the third blade 233 move in conjunction with the first blade 231 and function as a covering blade covering the opening.

The auxiliary arm 236 is pivotally supported by the shaft 201f on the first blade 231a side. The end side 331a of the first blade 331 of the light-shielding blade group 330 is a light-shielding end forming portion, and the sub-arm 336 is pivotally supported by a shaft 201g on the first blade 331a side.

FIG. 4 is an enlarged view of a part of the focal plane shutter according to the embodiment of the present invention. Further, FIG. 5 is a cross-sectional view taken along the line AA of FIG.

In FIG. 4, the main arm 235 is fitted with the fitting portion 202b of the blade driving member 202. Further, the sub-arm 236 is rotatably supported on the shaft 201f. A blade backlash spring 237 is hung on the auxiliary arm 236 so as to urge the blade group 230 in a counterclockwise direction, that is, in a direction in which the blade group 230 travels.

A hole (engagement hole) 235a for engaging with the drive pin 202a of the blade drive member 202, which will be described later, is provided at the base end portion of the main arm 235 on the side opposite to the side holding the blade. Has been done. For example, in the present embodiment, the drive pin 202a is erected on a flange portion 202A of the blade drive member 202, which is provided so as to project radially outward from the shaft (rotary shaft) 201a. A hole 235a of the main arm 235 is inserted through the drive pin 202a, and in that state, the tip of the main arm 235 is provided with respect to the concave fitting portion 202b provided on the flange portion 202A side of the blade drive member 202. The portion 235d is fitted, and the fitting portion 202b regulates the movement of the main arm portion 235 in the width direction (the direction intersecting the longitudinal direction from the hole 235a toward the tip portion 235d). As a result, the main arm 235 and the blade driving member 202 are connected, and the blade driving member 202 rotates around the shaft 201a, so that the main arm 235 rotates. The portion of the main arm 235 sandwiched between the hole 235a and the tip portion 235d is in a state of being pressed by a part of the cover member, which will be described later. As a result, in the present embodiment, the main arm 235 can rotate stably without being detached from the blade driving member 202.

The hole 235a fixes the main arm 235 in the radial direction of the shaft 201a, and the main arm 235 is engaged with the fitting portion 202b of the blade driving member 202 at the longitudinal end (tip portion 235d) of the main arm 235. Therefore, it is fixed around the drive pin 202a.

The fitting portion 202b is made of a resin material, and the tip portion 235d of the main arm is made of a metal plate having a thickness of about 0.1 mm. Since repeated impacts around the drive pin 202a are applied to the fitting portion 202b, the tip portion of the main arm It is preferable to form a standing bend at 235d to disperse the concentrated load on the fitting portion 202b by the outer peripheral end surface of the plate.

Although the drive pin 202a is circular in the present embodiment, it may be fixed around the pin such as a quadrangle, a polygon, or a star.

For example, if the cross-sectional shape of the drive pin 202a is sufficiently long in the longitudinal direction of the main arm, it is not necessary to engage at the end of the arm, and engagement or fitting may be performed at one location. That is, the main arm 235 does not have a hole corresponding to the axis (rotation center) 201a of the main arm 235, in other words, the main arm 235 side of the axis 201a which is the rotation axis of the main arm 235. It can be said that there is an engaging position of the main arm 235.

In this way, by providing the engagement position of the main arm 235 with the drive pin 202a (blade drive member) other than the rotation center of the drive pin 202a, the main arm 235 can rotate in synchronization with the rotation of the drive pin 202a. Therefore, it is possible to reduce the sliding load between the shutter base plate and the main arm 235.

FIG. 5 is a cross-sectional view of the shutter base plate 201 around the shaft 201a. As described above, since the main arm 235 does not have a hole corresponding to the rotation axis (shaft 201a) of the main arm 235, the blade group 230 can be pulled out to the lower side of FIG. 5 simply by removing the cover plate 206. The blade group 230 can be incorporated again. The cover plate 206 is also an example of an opening forming member that forms an opening through which light passes.

When the blade drive member 202 is driven, the main arm 235 is driven by the drive pin 202a. Further, since it rotates integrally with the blade driving member 202, sliding friction due to the rotating shaft 201a and the fitting portion 202b of the main arm 235 does not occur.

Further, the blade unit is arranged on one side of the shutter base plate 201, and the blade unit can be attached and detached without removing the drive member 202 from the shutter base plate 201.

FIG. 6 is a view in which the positional relationship of the cushioning members 242 and 243 is added to FIG. 4, and FIG. 7 is a perspective view showing a state immediately before the cushioning members 242 and 243 are attached to the cover plate 206. The end of the elongated hole 206f to which the cushioning members 242 and 243 are attached is viewed obliquely from the lower side to the upper side of FIG. 6 on the upper side of FIG. 6 (front of the paper surface).

The cushioning member 242 is made of an elastic material such as rubber, and its planar shape is a horseshoe shape. Further, overhanging portions 242g and 242h are formed and attached to the end of the elongated hole 206f of the cover plate 206.

Further, the lack of the overhanging portion on the 242h side escapes the operation locus of the dowel 238 constituting the blade group shown in FIG. 5 so as not to hinder the operation of the blade group. When the drive is completed, the blade drive member 202 collides with the cushioning member 243 on a plane perpendicular to the traveling direction of the drive pin 202a.

As a result, the impact propagates to the buffer member 242, the impact when the blade drive member 202 suddenly stops is absorbed by the buffer members 242 and 243, and the impact of the blade drive member 202 and the blade group 230 linked therewith is softened and durable. It is possible to improve the performance and suppress the bounce when the drive is completed.

Further, since the drive pin 202a collides with the cushioning member 243 made of resin, the drive pin 202a comes into direct contact with the cushioning member 242 formed of the rubber member, so that the rubber surface is adhered and the blade driving member 202 is operated. Does not interfere with.

Here, the mounting configuration of the buffer members 242 and 243 will be described with reference to FIG.

As can be seen from FIGS. 7 (A) and 7 (B), at one end of the elongated hole 206f in the length direction, along the arcuate edge thereof, the outer surface of the blade chamber of the cover plate 206 (upper of FIG. 7 (A)). ) Side has one overhanging portion 206g and a recess 206h is formed on the blade chamber surface (lower side of FIG. 7A), and the overhanging portion 206g is a cushioning member in a direction along a substantially extension line direction of the elongated hole 206f. It is arranged so as to protrude from 242.

Then, in the case of the present embodiment, as can be seen from FIGS. 6, 7 (A) and 7 (B), the cushioning member 242 is such that the overhanging portion 206g of the cover plate 206 and the recessed portion 242g of the cushioning member 242 are fitted to each other. It is arranged and does not protrude to the outer surface side of the blade chamber of the cover plate 206.

Further, the cushioning member 243 is arranged so that the concave portion 206j of the cover plate 206 and the convex portion 243j of the cushioning member 243, and the concave portion 206k of the cover plate 206 and the convex portion 243k of the cushioning member 243 are fitted to each other.

The convex portion of the cushioning member 243 shown in FIG. 7A on the inner surface side of the blade is provided only on the convex portion 243k side, but the cushioning member shown in FIG. 7B is shown. The member 243 is provided on the convex portion 243j side in the same manner as on the convex portion 243k side, and is in another form in which the mounting stability thereof is improved.

As described above, the cushioning members 242 and 243 of the present embodiment are composed of two members, the cushioning member 243 that comes into contact with the drive pin 202a, and the cushioning member that is fixed to the end side of the drive pin 202a of the cover plate 206 in the traveling direction. It is composed of 242. Any cushioning member may be made of an elastic resin material, but the material has a relationship in which the elasticity of the cushioning member 242 is weaker than that of the cushioning member 243.

As a more preferable example, as shown in FIG. 7C, the cushioning member 342 on the light-shielding blade group 330 side is formed of rubber, the cushioning member 343 is formed of resin, and the buffer member 242 and the buffer member 243 on the blade group 230 side are formed. It may be integrally formed of rubber. By doing so, when the device is stored, the cushioning property of the cushioning member 342 is ensured while preventing the drive pin 302a on the light-shielding blade group 330 side, which is in contact with the cushioning member 343, from sticking to the cushioning member 343. Since the drive pin 202a is held in a state where it is not in contact with the cushioning member 243 when the device is stored, it can be easily formed and attached by a single member. Further, if the two members are formed, the fitting area with the cover plate 206 as the cushioning member becomes small, so that the cushioning member 243 tends to fall off during the operation. Therefore, by integrally forming the cushioning member 242 and the cushioning member 243, it is possible to prevent the cushioning member 243 (242) from falling off.

FIG. 8 is an enlarged view of the blade driving member 202. FIG. 9 is an exploded perspective view of the blade driving member 202.

The charge roller cover 214 has flexibility and has a crank shape as shown in FIG. 9, and the charge roller cover 214 attaches the charge roller 204a to a shaft 202e provided on the blade drive member 202. It is inserted and abutted against the armature support portion 202d, the roller shaft 202e, and the abutting portion 202f of the blade drive member 202 in the order of the abutting portions 214a, 214b, and 214c of the charge roller cover 214.

As a result, it is fixed to the blade driving member 202 and supports the charge roller 204a so that it can rotate suitably. Further, the charge roller 204a is positioned so as to come into contact with the charge cam 203. The light-shielding blade drive member 302 (see FIG. 14) that drives the light-shielding blade group 330 also has substantially the same configuration as the blade drive member 202 described above.

FIG. 11 is a front view of the charge cam 203, the cam phase plate 208, and the cam gear 209. FIG. 12 is an exploded perspective view of the charge cam portion.

Chi Yajikamu 203 is rotatably supported by a shaft 201c of the shutter base plate 201 (see FIG. 2).

Charge cam riding portion 203a formed in the cam 203 and the cam top portion 203b, the cam portion opening 203c in response to rotation of the direction of an arrow shown in FIG. 11 of the charge cam 203, the charge provided on the blade driving member 202 The blade driving member 202 is rotated in contact with the roller 204a.

Except for both ends of the cam riding portion 203a and the cam opening portion 203c, the cam top portion 203b and the center of the rotation axis have the same radius. Therefore, while the charge cam 203 rotates and is in contact with the cam portions other than both ends of the cam riding portion 203a and the cam opening portion 203c, the blade drive member 202 does not rotate, and the blade group 230 is outside the shutter aperture. Stays in place.

Further, the cam riding portion 203d, the cam inclined portion 203e, the cam top portion 203f, the cam inclined portion 203g, and the cam top portion 203h formed on the charge cam 203 rotate in the arrow direction shown in FIG. 11 of the charge cam 203. Correspondingly, the light-shielding blade drive member 302 is rotated by abutting against the charge roller provided on the light-shielding blade drive member 302.

The apex of the cam riding portion 203d is shorter than the apex of the cam top portion 203f from the rotation axis. The vertices of the cam top portions 203f and 203h are equidistant from the rotation axis, and the radius of the apex portion is smaller than the distance from the rotation axis to the apex.

The cam top portion 203h to the cam opening portion 203i have the same radius at the center of the rotation axis. The cam inclined portions 203e and 203g are cams connecting the cam riding portion 203d and the cam top portion 203f, and cams connecting the cam top portion 203f and the cam top portion 203h, respectively.

Therefore, the charge cam 203 rotates, and in the cam inclined portion 203e from the cam riding portion 203d to the cam top portion 203f, the light-shielding blade group 330 is charged at an intermediate position between the position where the light-shielding blade group 330 covers the aperture and the maximum charge position of the shutter. ..

After that, it returns to the middle between the intermediate position and the position where the aperture starts to be covered, and moves to the maximum charge position of the shutter.

Next, when the cam top 203f passes through the cam inclined portion 203g and reaches the cam top 203h, it temporarily returns to the middle between the intermediate position and the position where the aperture starts to be covered, and moves to the maximum charge position of the shutter again.

While in contact with the cam portion from the cam top 203h to the cam opening portion 203i, the light-shielding blade driving member 302 does not rotate, and the light-shielding blade group 330 remains at the maximum shutter charge position.

The cam phase plate 208 has a fitting portion 203l of the charge cam, a fitting portion 208e that is fitted and relatively positioned relative to the engaging portion 203m, and an engaging portion 208f, whereby the cam phase plate is integrated with the charge cam. Rotates in a positive manner.

The cam phase plate 208 is provided with a light-shielding portion 208a, and the light-shielding portion 208a shields the photosensor 217b to detect the rotation phase of the charge cam 203.

The photo sensor 217b and the light-shielding portion 208a of the cam phase plate 208 form the cam phase detecting means 95.

Here, the light-shielding portion 208a is formed so as to light-shield the photo interrupter in accordance with the phases of the cam top and the cam bottom.

The cam phase detection means 95 detects H when light is blocked and L when not light-shielded. The phase detection by the photo interrupter is non-contact, and the reliability is improved without detection failure due to dust or oil or scraping due to durability.

In the present invention, the charge cam 203 is arranged on the side distant from the optical axis from the blade driving member 202 in a plane perpendicular to the optical axis. Then, the charge cam 203 charges the blade driving member 202 and the light-shielding blade driving member 302 by the rotational movement.

Generally, the charge cam, cam gear, and phase plate are integrally molded, but the mold structure is complicated and it is difficult to obtain dimensional accuracy. In the present invention, by configuring the three bodies, it becomes easy to improve the dimensional accuracy of each body, and the assembling property is also improved.

The charge roller 204b is arranged on the light-shielding blade driving member 302 as shown in FIG. 14, and comes into contact with the cam surface formed on the charge cam 203.

The charge roller 204b has a sizing shape for adjusting the overcharge amount described later, and is replaced when the overcharge amount deviates from a certain standard.

The charge roller 204b is arranged on the upper surface side of the charge lever 260, that is, on the assembly direction side, and always overlaps with the flange 203d of the cam gear 209 shown in FIG. 11 so as not to come off.

With this configuration, the charge roller 204b can be replaced and the overcharge amount can be adjusted simply by removing the cam gear 209, so that assembly can be facilitated without increasing the number of parts.

On the other hand, since the charge roller 204a does not need to be replaced, it does not affect the change in inertia of the blade drive member 202, and the traveling characteristics of the blade group 230 are stabilized.

In the present embodiment, the blade drive member 202 is provided with the charge roller 204a, but the blade drive member 202 may be provided with a shape that directly contacts the charge lever 260.

As shown in FIG. 2, the rotation axis of the motor 220 has an output axis arranged in the direction of the mounting surface 201c of the shutter base plate 201 orthogonal to the photographing optical axis. More specifically, the output shaft (rotation axis) of the motor 220 is arranged in the longitudinal direction of the blade group 230, that is, in the traveling direction (deployment direction) of the blade group 230 and in the direction perpendicular to the optical axis direction.

As shown in FIG. 13, when the cam gear 209 is rotated by the driving force transmitted from the motor 220 and the motor pinion gear 220a via the reduction gears 221, 222, 223, and 224, which are transmission members, the charging operation described later and It is possible to perform a charge release operation.

As shown in FIG. 13, the rotating shafts 225a and 225b of the reduction gears 221 and 222 are arranged parallel to the motor rotating shaft, and the rotating shafts 225c and 225d of the reduction gears 223 and 224 are arranged parallel to the optical axis.

Therefore, the rotary shaft 225b and the rotary shaft 225c are orthogonal to each other and are formed radially from the motor gear base plate 225, respectively, and a bevel gear is used as the power transmission means from the reduction gear 222 to the gear 223.

The bevel gear can easily change the gear ratio in the same space simply by changing the reference pitch cone angle. The reference pitch cone angle of 45 degrees is 1: 1. For example, the reference pitch cone diameter of φ5.25 and the reference pitch circle diameter of φ3.6 are 55 ° 34'and 34 ° 26', and the gear ratio is 1. It becomes 46: 1.

Conversely, the reference pitch cone angles of the reference pitch circle diameter φ3.6 and the reference pitch circle diameter φ5.25 are 34 ° 26 ′ and 55 ° 34 ′, and the gear ratio is 0.69: 1.

As a result, at least three ways of changing the gear ratio can be performed in the same space, the gear ratio can be easily changed according to the motor performance, and the driving force transmission mechanism can be configured in a small space. Also contributes to the miniaturization of the imaging device.

FIG. 33 shows an excerpt of only the motor 220 and each gear. Assuming that FIG. 33 (A) shows the motor 220 and the gear as viewed from the direction perpendicular to the xy plane, FIG. 33 (B) is viewed from the direction perpendicular to the xy plane, and FIG. 33 (C) is viewed from the direction perpendicular to the yz plane. It is a figure of the state.

As is clear from FIG. 33, the driving force generated by the motor 220 is transmitted to the reduction gears 221 and 222, 223 and 224 via the motor pinion gear 220a, and the reduction gear 222 and the reduction gear 223 It is composed of bevel gears.

It meshes with the reduction gear 224 and the cam gear 209, and transmits the driving force transmitted to the reduction gear 224 to the cam gear 209.

The auxiliary base plate 205 shown in FIG. 2 is engaged with and attached to the tips of the shafts 201a, 201b, 201c of the shutter base plate 201 shown in FIGS. 2 and 14.

The electromagnet 250 is fixed to the auxiliary base plate 205 as shown in FIG.

FIG. 10 is a cross-sectional view of the electromagnet 250 as viewed from above in FIG. The electromagnet 250 has a yoke 251, a bobbin 252, a coil 253, and terminal pins 254a and 254b.

The yoke 251 has a substantially U-shape having two legs, and one of the two legs is provided with a bobbin 252 around which a coil 253 is wound. The terminal pins 254a and 254b connected to both ends of the coil 253 project from the surface of the bobbin 252.

The end surface (251a) of the leg portion on which the coil 253 is provided and the end surface (251b) of the other leg portion function as suction surfaces, and the area of 251b is smaller than the area of 251a. This is because the time from when the energization of the coil is stopped until the drive member is driven becomes constant, and the variation in the exposure time is suppressed.

Further, when a voltage is applied between the terminal pins 254a and 254b of the yoke 251, the coil 253 generates a magnetic flux.

The photosensors 217a and 217b are sandwiched between the shutter base plate 201 and the auxiliary base plate 205 as shown in FIG.

The blade driving member 202 is provided with a light-shielding portion 202c as shown in FIG. 4, and the light-shielding portion 202c shields the photosensor 217a to detect the rotation phase of the blade driving member 202.

As will be described later, the blade group 230 is expanded or superposed by the rotation of the blade driving member 202, and the photo sensor 217 detects the rotation phase of the blade driving member 202 to detect the opening of the blade group 230. It becomes possible to detect the position at 206a. The photo sensor 217a and the light-shielding portion 202c of the blade driving member 202 constitute the blade detecting means 93.

Here, the light-shielding portion 202c is formed so as to block light when the blade driving member 202 is set. The blade detecting means 93 detects H when light-shielding (set) and L when non-light-shielding (running is completed).

By the way, the rotation phase can be detected even if the cam phase plate 208 linked with the charge cam 203 is provided with two light-shielding portions so as to detect each of the cam top and the cam bottom. In that case, the two light-shielding portions are in phase. It is necessary to arrange it so as not to come into contact with the detecting means, and the chargicam 203 becomes large.

Further, since the charge cam 203 makes one rotation, the shutter device is enlarged by twice the radius of the large light-shielding portion.

In the present invention, one phase detecting means is provided for the charge cam 203 and one for the blade driving member 202. Since the light-shielding portion 208a of the cam phase plate 208 is arranged on the rotation center side of the cam surface of the charge cam 203, the shutter device is downsized.

Further, the blade driving member 202 is a reciprocating motion, and the shutter device becomes large only for the traveling locus of the light-shielding portion 202c.

Further, the light-shielding portion 202c has a degree of freedom in design as compared with providing another light-shielding portion on the rotating cam gear 209, and can be arranged according to the space in the image pickup device, so that the image pickup device can be miniaturized. Also contributes.

As shown in FIG. 2, the cover plate 206 is located closest to the subject in the unit configuration, and is on the same side in the order of the rear blade group 230, the partition plate 207, the light-shielding curtain group 330, the shutter base plate 201, and the auxiliary base plate 205. Have been placed.

The opening 201p of the shutter base plate 201 is provided at a position substantially coincident with the shutter aperture 206a provided at the center of the cover plate 206 in the optical axis direction.

The opening 201p of the shutter base plate has a larger opening than the shutter aperture 206a of the cover plate.

A blade chamber for arranging the rear blade group 230 and the light-shielding curtain group 330 is formed between the shutter base plate 201 and the cover plate 206, and a partition plate 207 for separating each curtain group is arranged.

Next, the configuration of the focal plane shutter 3 will be described in detail with reference to FIGS. 14 to 126.

14 to 26 are plan views viewed from the back in a state of being incorporated in the camera. In these drawings, the shutter base plate 201, the auxiliary base plate 205, the cover plate 206, the motor gear base plate 225, and the like are omitted for the sake of readability of the drawings.

FIG. 14 shows an overcharged state of the blade driving member, that is, a state in which the camera is stopped and a live view state.

15 is an excerpt of the blade group 230 of FIG. 14, FIG. 16 is a state in which the blade driving member is held by the electromagnet 250, FIG. 17 is a traveling state of the blade group 230, and FIG. 18 is a traveling state of the blade group 230. Indicates the completion status.

FIG. 19 shows a state in which the blade group is unlocked before charging, FIG. 20 shows a state in which the light-shielding curtain starts charging, and FIG. 21 shows a state in which the light-shielding curtain blocks approximately half of the aperture.

Further, FIG. 22 shows a state in which the light-shielding curtain completely blocks the aperture, FIG. 23 shows a state in which the light-shielding curtain rises to the highest point, and FIG. 24 shows a state in which the light-shielding curtain is at the midpoint between the highest point and the aperture fully closed.

Further, FIG. 25 shows a light-shielding curtain overcharged state, and FIG. 26 shows a state in which the light-shielding curtain is held by an electromagnet.

As shown in FIG. 4, a drive pin 202a is formed at the tip of the blade drive member 202, and the drive pin 202a is engaged with the hole 235a of the main arm 235.

When the drive pin 202a moves along the elongated hole 206f due to the rotation of the blade drive member 202, the main arm 235 rotates to deploy or superimpose the blade group 230. By the operation of the blade group 230, the opening 206a can be brought into an open state (a state in which the subject luminous flux passes) or a substantially closed state (a state in which the subject luminous flux is substantially blocked).

15 to 18 are excerpts for explaining the operation of the blade group 230, and FIG. 17 shows an opening of the exposure control end surface 231a of the first blade 231 during the exposure control operation from FIG. 15 to the state of FIG. It shows a state in which approximately half of the light is shielded. In the exposure control end face 231a, the end face formed by punching is further made uniform by laser processing.

The blade drive member 202 has a fitting portion 202b provided in the vicinity of the rotation hole 202a between the blade drive pin 202a and the rotation hole of the blade drive member, and is fitted (engaged) with the end portion 235d of the main arm. (Fig. 4), the main arm 235 that pivotally supports the first blade 231 is rotated around the rotation hole 202a of the blade drive member.

In the process of blade traveling during exposure from the state of FIG. 14 to the state of FIG. 18, the driving force is transmitted to the first blade 231 via the transmission unit 235c opposite to the exposure control end surface 231a side, and the first blade 231 is the sub arm. It works by pushing out 236.

As a result, the sub arm 236 operates while being pushed out by the main arm 235. The 2nd blade 232 and the 3rd blade 233 also operate in the same manner as the 1st blade 231 and push out the sub arm 236, but the 1st blade 231 has the largest amount of operation, and the 2nd blade 232 and the 3rd blade 233 operate. The amount will gradually decrease.

Due to the arrangement of the driving force transmitting unit 235c of the first blade 231, the driving force transmitted unit 235c is delayed from the exposure control traveling direction with respect to the center of gravity of the first blade 231, and the first blade 231 is pushed out by the main arm 235. Operate.

Similarly, the 2nd blade 232, the 3rd blade 233, and the 4th blade 234 are also pivotally supported by the respective driving force transmission parts of the main arm 235, and the position where the driving force transmission part is delayed from the exposure control traveling direction from the center of gravity of each blade. It is arranged in (Fig. 4).

In this way, the blade driving member 202 rotates the main arm 235 pivotally supported on the side opposite to the exposure control end surface 231a side via the driving force transmission unit 235c.

At this time, since the backlash spring 237 applied to the sub-arm 3236 applies a driving force in the traveling direction to the sub-arm 3236, the blades start smoothly and the exposure control end surface 231a shakes in the optical axis direction. It can run stably without any problems.

On the other hand, the efficiency of the driving force transmission of the blade driving member 202 in the state of starting the traveling of the blade group 230 and the state of completing the traveling is substantially the same, and the traveling characteristics can be stabilized.

Further, although the blade group 230 connected to the main arm 235 itself is pushed out, the backlash spring 3237 reduces the tilt of the sub arm 236 and the main arm 235 in the optical axis direction, and the driving force can be efficiently transmitted.

In the embodiment, the main arm 235 does not have a hole corresponding to the rotation axis of the drive member, and only the blade unit can be replaced with the drive member incorporated.

Therefore, the blade drive member 202 and the main arm 235 are separate members, but the members are integrated by, for example, fastening, heat welding, integral molding of mold inserts, outserts, etc., and the tilt of the main arm in the plate thickness direction is increased. When suppressing, at least one fixing portion is provided at the position of the drive pin 202a.

When the blade travel of FIG. 18 is completed, the rear curtain lock lever 255 locks the blade drive member 202 so as not to return in the left shift direction, and prevents the end surface 231a of the first blade from returning to the aperture and re-exposure. ing. Immediately after the exposure, the blade group is charged.

19 to 26 are excerpts for explaining the charging operation of the light-shielding blade group 330, and FIG. 22 shows the exposure control end surface 231a of the first blade 331 during the charging operation from FIG. 19 to the state of FIG. 26. It shows a state in which the entire opening is shielded from light.

In FIG. 19, when the charge cam 203 is turned to the right, the light-shielding curtain lock lever 256 receives an acting force from the contact portion with the cam 203 and turns to the left, and the light-shielding curtain lock lever claw is turned from the lock portion 302 g of the light-shielding blade drive member. The part 256a is released to release the lock. At the same time, the rear curtain lock lever 255 is connected to the light-shielding curtain lock lever 256 and turns to the right by the acting force from the light-shielding curtain lock lever 256, and the hook portion 255a of the rear curtain lock lever is from the notch portion 202g of the blade drive lever. Unlock and unlock.

As shown in FIG. 20, when the charge cam 203 further turns to the right, the shading curtain starts shading the aperture. Until this time, charging of the blade group 230 is not started.

As shown in FIG. 21, when the charge cam 203 further turns to the right, the light-shielding end surface 331a of the light-shielding blade group 330 shields half of the aperture, and at this time, the exposure control end surface 231a of the rear blade group and the light-shielding blade group The light-shielding end surface 331a of the above keeps a desired distance and is charged upward in the figure while maintaining the light-shielding state.

As shown in FIG. 22, when the charge cam 203 further turns to the right, the light-shielding end surface 331a of the light-shielding blade group reaches the aperture 206a, and the exposure control end surface 231a of the rear blade group and the light-shielding end surface 331a of the light-shielding blade group are desired. It is charged late while keeping the distance.

As shown in FIG. 23, the exposure control end face 231a of the rear blade group reaches the highest point in a state where the light-shielding end surface 331a of the light-shielding blade group reaches the highest point of operation by further turning the charge cam 203 to the right. To do.

With the conventional shutter, the setting is completed here, and the next release is awaited. However, in the present invention, as shown in FIG. 24, the exposure control end surface 231a of the rear blade group is maintained at the highest point by further turning the charge cam 203 to the right.

On the other hand, the light-shielding end surface 331a of the light-shielding blade group descends to a range where the inside of the aperture 206a is not exposed, and as shown in FIG. 25, the charge cam 203 further turns to the right, so that the light-shielding end surface 331a of the light-shielding blade group operates again. It rises to the highest point (overcharge) of. At this point, energization is started on the electromagnet 350 to which the armature 312 is attracted.

As shown in FIG. 26, when the charge cam 203 further turns to the right, it passes through the cam opening portion 203i that has charged the light-shielding blade drive member 302, and the mechanical holding is lost.

At this time, since the electromagnet 250 is energized, the armature 312 is attracted and held, and the light-shielding blade group 330 keeps the aperture light-shielded.

After the reading of the sensor is completed, the energization of the electromagnet 250 is cut off, the light-shielding blade group 330 opens the aperture, and returns to the shutter standby state of FIG.

In the present invention, in the series of light-shielding curtain charging operations, the rear blade group is charged during the reading time of the sensor after exposure control.

The light-shielding blade group charges before the rear blade group and continues to shield the aperture while maintaining a constant overlap with the rear blade group that charges later.

In addition, since the rear blade group is arranged on the lens side and the light-shielding blade group is arranged on the sensor side, the light-shielding blade group is closer to the focal point than the rear blade and is disadvantageous to the condensed sunlight than the rear blade. In order to shorten the stop time while the aperture is shielded from light, the blades are swung and kept moving to shorten the stop time.

The purpose is to keep the aperture closed and to protect the rear blades of the exposure control from sunlight, and the light-shielding blades are not used directly for the exposure control.

Reading time of the conventional sensor is 150 μsec. During that time, the rear blade group shielded the aperture so that the aperture would not be released, and opened the aperture after the read time. Further, even during the reading time, the stopped resin blades are damaged by the condensed sunlight, so the blades are made of metal blades or the like.

The charge roller 204a is arranged on the 260-blade drive member 202 as shown in FIG. 9, and is in contact with the cam surface formed on the charge cam 203 like the charge roller 204b.

Like the charge roller 204b, the charge roller 204a has a sizing shape for adjusting the overcharge amount described later, and is replaced when the overcharge amount deviates from a certain standard.

The charge roller 204a is arranged on the upper surface side of the blade drive member 202, that is, on the assembly direction side, and overlaps the flange 214b of the roller cover 214 shown in FIG. 9 so as not to be pulled out at all times.

In the present embodiment, the blade drive member 202 is provided with the charge roller 204a, but the blade drive member 202 may be provided with a shape that directly contacts the charge cam 203.

Here, how the light-shielding curtain lock lever 256 and the rear curtain lock lever 255 are urged by the rotation of the charge cam 203 will be described.
FIG. 27 shows the state when the blade travel of FIG. 18 is completed, and the rear curtain lock lever 255 locks the blade drive member 202 so as not to return in the left shift direction.

FIG. 28 shows an enlarged view around the charge cam 203 at the position of FIG. By turning the charge cam 203 to the right, the light-shielding curtain lock lever 256 receives an acting force from the contact portion with the cam 203 and turns to the left, and the light-shielding curtain lock lever claw portion 256a comes off from the lock portion 302 g of the light-shielding blade drive member. To unlock. At the same time, the rear curtain lock lever 255 is connected to the light-shielding curtain lock lever 256 and turns to the right by the acting force from the light-shielding curtain lock lever 256, and the hook portion 255a of the rear curtain lock lever is from the notch portion 202g of the blade drive lever. Unlock and unlock.

FIG. 29 is an enlarged view of the vicinity of the charge cam 203 at the position of FIG. 24, and is a state in which the rear curtain drive lever 300 is turned to the left by the charge cam 203 and charging is completed.

FIG. 30 is a diagram showing a state in which the charge cam 203 is further rotated from the state of FIG. 29 to approach the initial state of FIG.

The urging of the light-shielding curtain lock lever 256 from the charge cam 203 is released, and the light-shielding curtain travels to return to the pre-shooting preparation state. The rear curtain lock lever 255 is spring-urged in the direction of turning left, and the rear curtain lock lever 255 locks the blade drive lever 202 in conjunction with the light-shielding curtain lock lever 256 turning right and returning to the locked state. Move to a possible position.

<Explanation of operation>
FIG. 31 shows the operation timing of each component of the shutter device 3 and the image sensor 2. The movement of each component and the imaging operation will be described with reference to FIGS. 14 to 26 and 27. The circled numbers 1 to 10 in FIGS. 31 and 32 correspond to the respective operating states described later.

In No. 1 of FIG. 31, the shutter device 3 is in an overcharged state as shown in FIG. 14, and the rear blade group 230 and the light-shielding blade group 330 are superimposed, so that the subject luminous flux is passed through.

The live view imaging operation described above is performed on the camera, and a subject image incident on the image sensor 2 is displayed on an image display unit (not shown).

At this time, it is checked whether or not the blade detecting means 93 and the cam phase detecting means 94 are each H. That is, it is confirmed that the blade driving member 202 is in the set state and that the charge cam 203 is the cam top.

If the blade detecting means 93 or the cam phase detecting means 94 is L, the motor 220 is energized so that both become H.

Here, in the present invention, since the phase detection of the cam gear 209 is performed by one of the cam phase detection means 94, both the cam top and the cam bottom are H.

On the other hand, by performing phase detection of the blade driving member 202 by the blade detecting means 93 and confirming that the blade driving member 202 is in the set state, it can be seen that the charge cam 203 is the cam top.

When the release operation is started (No. 2 in FIG. 31), the coil 253 is energized and a magnetic force is generated in the yoke 251 to bring the yoke 251 and the armature 212 into an attracted state.

In the magnetic circuit formed by the yoke 251 and the armature 212 in the present embodiment, the portion having the smallest cross-sectional area in the circuit is the armature portion.

Therefore, the magnetic flux generated in the magnetic circuit is determined by the amount at which the magnetic flux density of the armature cross section is saturated. Here, the amount of magnetic flux generated in the armature cross section is ΦA.

Usually, in a magnetic circuit, there is a magnetic flux leakage into the air. Therefore, the magnetic flux ΦY1 generated on the suction surface 251a of the yoke, which is closer to the coil 253 which is the source of the magnetic flux than the armature 212, is larger than that of ΦA.

On the other hand, the magnetic flux ΦY2 generated on the suction surface 251b of the yoke, which is farther from the coil 253 which is the source of the magnetic flux than the armature 212, is smaller than that of ΦA. Further, the magnetic attraction force acting on the attraction surface can be expressed by using the following equation.

Here, F is the attractive force acting on the attractive surface, μ is the magnetic permeability, B is the magnetic flux density of the attractive surface, S is the area of the attractive surface, and Φ is the amount of magnetic flux. As described above, the magnetic flux generated on the suction surfaces 251a and 251b is ΦY1> ΦY2. In the present embodiment, since the adsorption area of 251a is larger than that of 251b, the adsorption force generated on each surface can be made substantially equal.

After the yoke 251 and the armature 212 are brought into the suction state, or almost at the same time, the motor is energized to rotate the charge cam 203 in the clockwise direction of FIG.

The charge roller 204a moves from the cam top portion 203b of the charge cam 203 to the cam opening portion 203c, the charge cam 203 is gradually retracted to the cam inclined portion 203n to release the overcharge, and the blade group 230 shown in FIG. 16 travels. It shifts to the previous standby state.

Then, the cam phase detection means 94 detects L from H, and the motor 220 stops (No. 3 in FIG. 31).

At number 4 in FIG. 31, all the pixels of the image sensor 2 are reset. Next, at number 5 in FIG. 31, electronic front curtain scanning is started. This electronic front curtain scanning has a scanning pattern that matches the traveling characteristics of the blade group 230.

When the coil 211 is turned off at the number 6 in FIG. 31 after the time interval corresponding to the set shutter second is set, the suction force acting between the yoke 251 and the armature 212 disappears, and the blade driving member 202 , The torsion coil spring starts to rotate clockwise.

At that time, as described above, since the suction forces acting on the two suction surfaces of the yoke 251 and the armature 212 are substantially equal, the two suction surfaces are separated from each other at substantially the same time. Therefore, the variation in the drive timing of the blade drive member 202 when the energization is cut off is suppressed.

As the blade drive member 202 travels, its drive pin 202a comes into contact with the contact portion 243a of the cushioning member. After that, the cushioning member 243 is compressed by the elastic member 242 to absorb the impact and stop.

In this way, the blade driving member 202 and the main arm 235 are effectively absorbed by the elasticity of the cushioning member 243, the contact portion 243a, and the elastic member 242, and the exposure traveling of the blade group 230 is completed (FIG. 6). ). As a result, the opening 201p is in a state where the subject luminous flux is blocked as shown in FIG. 16 (No. 7 in FIG. 31).

When the traveling of the blade group 230 of the shutter device 3 is completed and the image sensor 2 is completely shielded from light, the still image reading scan is started.

At this time, it is checked whether or not the blade detecting means 93 and the cam phase detecting means 94 are each L. That is, it is confirmed that the blade driving member 202 is in the traveling completed state and that the cam gear 209 is the cam bottom.

If the blade detecting means 93 or the cam phase detecting means 94 is H, an abnormal state of the blade group 230 or the blade driving member 202 is suspected, so the imaging operation is stopped and an error is displayed on the display unit 7.

It is necessary to keep the subject luminous flux in a state where the charge reading is not completed. After a predetermined time (No. 8 in FIG. 31) from the start of reading the electric charge of the image sensor 2, the motor 220 is energized and the cam gear 209 is rotated counterclockwise.

The cam gear 209 pushes the charge roller 204, and the blade drive member 202 rotates clockwise against the urging force of the torsion coil spring to be charged.

The blade group 230 is gradually superimposed, and the opening 201p is sequentially opened from the pixel 1st row side of the image sensor 2. Therefore, along with the charge operation, the blade group 230 is opened in parallel with the charge reading.

At this time, the blade group 330 and the blade group 230 shield the opening so that the light leaked from the open portion of the blade group 230 does not enter the pixels in the row that the still image reading scan has not yet reached. The charge start time, which is number 8 in FIG. 31, is adjusted to a predetermined value so as to continue.

In the present invention, after the cam phase detection means 94 detects that the cam phase detection means 94 has changed from L to H, the motor 220 is stopped, and the charge reading of the image sensor 2 is completed, the light-shielding blade group 330 is energized by the electromagnet 350. After being cut, the light-shielding blade drive member 302 turns to the right by the urging force of the blade drive spring 341.

As shown in FIG. 15, the light-shielding blade drive member 302 is in the completed running state, the light-shielding blade group 330 releases the light-shielding of the aperture 206a, and the blade drive member 202 remains in the overcharged state. Therefore, the blade group 230 shields the aperture 206a. It will be in a fully open state.

When the charging operation is completed, the live view imaging operation for the moving image shooting or the electronic viewfinder function described above is started after the specified time.

Conventionally, after the charge reading of the image sensor 2 is completed (No. 9 in FIG. 32), the motor 220 is started, the blade group 230 is completed to superimpose, and the cam phase detection means 94 is changed from L to H. Is detected, the motor 220 is stopped (No. 10 in FIG. 32), and the blade drive member 202 is in an overcharged state as shown in FIG.

When the charging operation is completed, the live view imaging operation for the moving image shooting or the electronic viewfinder function described above is started after the specified time.

Further, in the shutter used in a camera having a mirror, the blade driving member and the blade operating member are separately formed, and the blade driving member is charged at the time when the electric charge of the image sensor 2 is read out, so that the electric charge of the image sensor 2 is charged. After the reading is completed, there is an arm spring in the direction opposite to the blade drive spring to return to the overcharge position. However, when this is used as a shutter for a mirrorless camera, metal blades are used in order to prevent blade damage due to condensed sunlight.

Here, the present invention is not limited to the above-described embodiment, and may be configured by, for example, appropriately combining one feature or a plurality of features described below.

<Arm fixing structure>
Here, as the focal plane shutter for a camera, it is also possible to have a structure in which a shaft and a drive pin are erected on the blade drive member and each of them is inserted into a hole provided in the arm of the blade to be interconnected. , In such a structure, it is necessary to provide two holes in the arm, which is disadvantageous in miniaturization.

In one aspect of the present invention, a first opening forming member (for example, a shutter base plate 201) forming a first opening through which light passes and a first opening of the first opening forming member are opposed to each other and light is emitted. In a focal plane shutter for a camera in which a blade chamber in which a shutter blade group travels is formed between a second opening forming member (for example, a cover member 206) that forms a passing second opening, a shutter blade group (for example, for example). The arm member includes an arm member (for example, main arm 235) to which the blade members 231, 232, 233) are connected, and a rotating member (for example, the blade driving member 202) for transmitting power to the arm member. The structure may be characterized in that it does not have a hole corresponding to the rotation axis of the arm member. As a result, the structure of the arm member is simplified, which is advantageous for miniaturization.

Here, as a configuration in which the arm member does not have a hole corresponding to its rotation axis, for example, the following structure is included. Specifically, taking the structure in one embodiment described above as an example, in the structural examples shown in FIGS. 4 and 5, the flange portion 202A is directed outward in the radial direction from the end portion of the blade driving member 202 serving as the rotating member. Is projected, and the drive pin 202a is provided on the flange portion 202A. Then, the drive pin 202a is inserted into the hole 235a penetrating the main arm 235 in the thickness direction, and the end portion 235d of the blade arm member 235 (that is, the side of the main arm 235 opposite to the side on which the shutter blade is mounted). The structure is such that a part of the end portion) is fitted to the fitting portion 202b which is a concave groove of the blade driving member 202. In this case, the main arm 235 rotates around the rotation axis of the blade drive member 202, but the drive pin 202a has a structure in which the drive pin 202a is engaged with the main arm 235 at a position away from the rotation axis. That is, the main arm 235 does not have a hole corresponding to its rotation axis, and has a structure in which the hole 235a is provided at another position. In the fitting portion 202b, an adhesive may be applied and adhesively fitted, or the tip end portion of the main arm 235 may be inserted and fitted into the fitting portion 202b to be fixed, or the cover plate 206 may be used. A structure may be adopted in which the end portion 235d of the main arm is pressed or covered on the blade driving member 202 side to prevent the main arm 235 from rising.

According to such a structure, the engagement relationship between the main arm 235 and the blade driving member 202 is completed at the portion between the blade driving member 202 and the shutter blade, which is advantageous for miniaturization or thinning. The structure is also excellent in assemblability. That is, the arm can be easily attached by inserting the hole 235a of the main arm 235 into the drive pin 202a while the end portion 235d of the main arm 235 is inserted into the concave groove of the fitting portion 202b. , The length of the main arm 235 can also be shortened. Further, the sliding load between the shutter base plate and the main arm 235 can be significantly reduced.

Even if the blade chamber, which is the traveling space for the shutter blades, and the drive system such as gears and drive members for driving the shutter blades are arranged on different flat surfaces with the shutter base plate in between, the space is effectively used. It can be used and can be miniaturized. Furthermore, by arranging the shutter blades and the drive system on the same surface side of the shutter base plate, it took time to replace the blades, but the blades can be easily replaced by simply removing the cover plate without removing the drive unit. It becomes.

When two sets of the above-mentioned main arms 235 are provided, one of which is the front curtain group and the other of which is the rear curtain group to form a focal plane shutter, they may have different structures, but they have substantially the same shape. It is preferable to adopt a configuration (particularly, a connecting structure of the blade arm member 235 and the blade driving member 202). As a result, it is possible to standardize the parts and realize a structure having excellent assemblability.

<Composition of shading curtain>
Here, in the focal plane shutter for a camera, if the exposure traveling is performed using the front blade group and the rear blade group, an extra time is required for the traveling time of one of the blade groups, and the frame speed is increased. It will be disadvantageous for up.

In another aspect of the present invention, the structure of the focal plane shutter for a camera described above, that is, the shutter base plate 201 having an opening for exposure as shown in FIG. 2 or 3, is opposed to the opening. In a focal plane shutter for a camera in which a blade chamber is provided in which a blade group, which is a shutter curtain traveled by each drive member, is provided between a cover member 206 having an opening for exposure, the blade members 231,232, The blade arm members 235 and 236 that drive the 233 and the blade members 231, 232, and 233 in the direction of closing the opening by link drive, the blade drive member 202 having the attraction member of the electromagnet, and the blade members 331, 332, and 333. The blade arm members 335 and 336 that cause the blade members 331, 332, and 333 to travel in the direction of opening the opening by link drive, and the blade drive member 302 having an electromagnet attraction member, and are exposed at the time of shooting. The structure may be characterized in that it has a rear blade group for performing an operation and another blade group for maintaining a fully closed state of the opening 206a during charging in cooperation with the rear blade group. In this case, the blade group for maintaining the fully closed state of the opening 206a in cooperation with the rear blade group during charging serves as a light-shielding curtain. This is advantageous for increasing the frame speed of the camera.

In the focal plane shutter for a camera having such a light-shielding curtain, for example, the blade group not involved in the exposure amount control receives a traveling signal (PI, contact signal, etc.) of the blades involved in the exposure amount control and charges the blade group. The blade group that is not involved in the exposure amount control can attract the (electric) magnet that keeps the opening closed in the light-shielding state, and at the same time as the reading time of the sensor ends, the blade group that is not involved in the exposure amount control can block the light. May be canceled.

In this way, by providing a light-shielding curtain (shielding film) that has two blade groups and shields the aperture in conjunction with the charge of the rear curtain that opens the aperture, it is rearward during the reading time of the image sensor after exposure. Since the curtain charge is completed and the light-shielding curtain opens the aperture by the next release, the time can be shortened and the frame speed of the camera can be increased. In addition, during the read time, the light-shielding curtain and the rear curtain are charged in sequence to shorten the time of exposure to condensed sunlight, and since resin blades can be used, the charge load is reduced, reducing current consumption and coma. It can contribute to speeding up.

Further, in the focal plane shutter for a camera, for example, on the blade drive member 202, an engagement portion 202b with an end portion 235b of the blade arm member 235 is arranged between the drive pin 202a and the drive shaft 201a. It may be done. As a result, the connecting structure between the blade driving member 202 and the blade arm member 235 becomes stronger.

In the focal plane shutter for a camera having the light-shielding curtain, the blade group involved in the exposure amount control is preferably black, and the blade group not involved in the exposure amount control is preferably white or silver. By doing so, good light-shielding performance can be obtained.

<Gear connection structure>
Here, the focal plane shutter may have a structure in which motors are erected in the optical axis direction corresponding to the first and second shutter curtains at the end of the shutter base plate having an opening. The structure may be disadvantageous for miniaturization of the main body of the image pickup device such as a camera.

As another aspect of the present invention, an opening forming member for forming an opening through which light passes, a group of blades traveling with respect to the opening, and a power transmission member for transmitting power for traveling to the group of blades. And a driving means (for example, a motor) for rotationally driving the power transmission member, and the driving means is attached to the opening forming member in an arrangement in which the rotation axis is orthogonal to the optical axis passing through the opening. , The power transmission member has a gear train in which a plurality of gears are connected, and in this gear train, the rotation axes are orthogonal to each other so as to convert the rotation of the driving means into the rotation around the axis parallel to the optical axis. The configuration may include a plurality of bevel gears connected together, and the rotational force transmitted through the plurality of bevel gears may be used for traveling the blade group through the power transmission member. By using a plurality of bevel gears in this way, it is possible to prevent the drive means from protruding in the optical axis direction, which is advantageous for miniaturization of the blade drive device.

The blade drive device having such a power transmission structure (for example, a focal plane shutter for a camera) has a structure in which power is transmitted by a gear train using a plurality of bevel gears (for example, reduction gears 222 and 223). Therefore, for example, the blade drive device can be downsized as compared with the case where the drive means is arranged so that the rotation axis is parallel to the optical axis. Further, by changing at least one of the plurality of bevel gears or a combination thereof (that is, changing the pitch cone angle of the bevel gears), it is easy to change the gear ratio or adjust the acceleration / deceleration. Therefore, for example, in the case of a focal plane shutter, the speed of the charge time can be freely changed, and the same shutter structure can be used for each sensor having a different read time.

The power transmission will be specifically described with reference to the figure. As shown in FIG. 14, the motor 220 is arranged so as not to overlap with respect to the longitudinal direction of the opening 206a formed in the shutter base plate 201. Although the opening 206a is arranged so as not to overlap with each other in the lateral direction in FIG. 14, the motor 220 is arranged on one side of the shutter base plate 201, and the main arm 335 and the sub arm 336 are arranged on the other side. If they are arranged on the direction side, they do not interfere with each other, so that they can be arranged so as to overlap each other in the lateral direction.

The driving force of the motor pinion gear 220a of the motor 220 is transmitted to the reduction gear 221 and the reduction gear 222 having a rotation axis parallel to the rotation axis of the motor. The reduction gear 222 is a bevel gear, has a rotation shaft parallel to the optical axis, that is, perpendicular to the opening 206a, and is driven and transmitted to the reduction gear 223 formed by the bevel gear. The driving force of the motor 220 transmitted to the reduction gear 223 is transmitted to the cam gear 209 via the reduction gear 224 to drive the charge cam 203 to move the rear blade group 230 and the light-shielding blade group 330 into the opening 206a. Drive to move forward and backward. In the present embodiment, both the rear blade group 230 and the light-shielding blade group 330 extend in parallel with the longitudinal direction of the opening 206a, and advance and retreat into the opening 206a perpendicular to the longitudinal direction of each blade group.

Here, when the drive is transmitted from the reduction gear 222 to the reduction gear 223, the rotation axis of the gear is turned 90 degrees. Since the rotation axis of the reduction gear 221 and the reduction gear 222 is parallel to the rotation axis of the motor, the dimensions of the opening 206a in the longitudinal direction can be suppressed.

By transmitting the driving force from the motor 220 in the lateral direction of the opening 206a by the reduction gear 221 and the reduction gear 222, the longitudinal dimension of the opening 206a is suppressed, and a gear having a large diameter with respect to the optical axis is not used. The driving force can be transmitted toward the central portion of the opening 206a in the lateral direction.

As a result, the reduction gear 223 is arranged at a position that does not overlap with the motor 220. More specifically, the reduction gear 223 is arranged at a position where it overlaps with the motor 220 in the lateral direction of the opening 206a, and is arranged at a position where it does not overlap with the motor 220 in the longitudinal direction of the opening 206a.

With this arrangement, the rotation axis of the gear can be turned 90 degrees by effectively utilizing the space without extending the dimension of the opening 206a in the longitudinal direction. That is, the motor 220 can be moved closer to the center of the opening 206a, or the proportion of gears in the longitudinal direction of the opening 206a can be reduced.

<Stopper structure>
In another aspect of the present invention, an opening forming member that forms an opening through which light passes, and a blade member that enters and exits the opening (may be a blade or a blade arm member on which the blade is mounted). A power transmission member that engages with the end of the blade member and transmits power to the blade member is provided, and the power transmission member is inserted into an elongated hole that penetrates the end of the opening forming member in the thickness direction. It has a drive pin that engages with the end of the blade member in the state, and the drive pin moves along the elongated hole to transmit power to the blade member, and the drive pin hits one end of the elongated hole. A stopper portion is provided to contact and stop the operation of the drive pin, and this stopper portion has a structure in which an elastic member with which the drive pin abuts is engaged with a cushioning member having a lower elasticity than this elastic member. May have a structure characterized in that it is embedded in one end side of an elongated hole among the opening forming members.

For example, in the case of the structural examples shown in FIGS. 2, 3 and 7, an auxiliary base plate 206 forming at least one blade chamber between the shutter base plate 201 made of synthetic resin and the shutter base plate 201 and an opening are provided. An exposure control blade 231 having an exposure control side that opens and closes to control exposure, a blade group 230 having blades 232 and 233 connected thereto, and two arms 235 and 236 that rotatably connect and support the blade group 230. The blade group 230 is opened and closed by a drive pin that is rotatably attached to the outer surface of the blade chamber of the shutter base plate 201, penetrates an arcuate elongated hole formed in the auxiliary base plate, and is connected to one of the arms. From the cushioning member 202, which is made of an elastic material and is attached to one end of an elongated hole and is abutted by a driving pin, and is located between the cushioning member 243 and the auxiliary base plate 201. The cushioning member 243 has an elastic member 242 having elasticity, the cushioning member 243 has a recess and at least one overhanging portion, and the auxiliary base plate has an overhanging portion formed on one end of an elongated hole on the surface side outside the blade chamber, and the surface inside the blade chamber. The cushioning member has a recess on the side, and the recess and the overhanging portion of the cushioning member are in contact with the overhanging portion of the auxiliary base plate and the recessed portion. It is preferable to use a stopper structure formed within the thickness of the main plate.

In the case of the stopper structure shown in FIG. 7 or the like, the elastic member 242 has a recess and at least one overhanging portion, and the auxiliary base plate has an overhanging portion formed on one end of the elongated hole on the surface side outside the blade chamber. , The surface side of the blade chamber has a recess, and the elastic member has a recess and an overhanging portion in contact with the overhanging portion of the auxiliary base plate and the recessed portion, and is formed at least on the surface side of the blade chamber. The overhanging portion of the member may be formed within the thickness of the auxiliary base plate. As a result, a cushioning member that the drive pin of the drive member comes into contact with at the end of the exposure operation can be suitably attached to the shutter base plate, and a focal plane shutter for a camera or the like having excellent airworthiness without being restricted by design. The blade drive device can be realized.

In the above embodiment, as the explanation of the live view mode, the one by the electronic front curtain control has been described, but after the release, the light-shielding blade group is once expanded, the opening is completely closed, and the light-shielding blade is used as the front curtain. Shooting in the live view mode may be realized by using the exposure control blade as a rear curtain. However, the electronic front curtain control described in the above embodiment is more advantageous in increasing the frame speed, in addition to being able to quickly return to the live view mode again when the image reading is completed.

1 Lens 2 Image sensor 3 Focal plane shutter 11 Shutter drive circuit 91 Voltage detection means 92 Temperature detection means 93 Blade detection means 94 Lens control means 95 Cam phase detection means 100 Image pickup device 201 Shutter base plate 201a Drive shaft (rear curtain)
201b Drive shaft (light-shielding curtain)
201c Charge shaft 201f Sub-arm shaft (rear curtain)
201g Sub-arm shaft (light-shielding curtain)
201h Mounting surface 201p Opening 202 Blade drive member (rear curtain)
202a Drive pin 202b Fitting part 202c Light-shielding part 202d Armature support part 202e Roller shaft 202f Contact part 202g Notch part 203 Charge cam 203a Cam riding part (rear curtain)
203b Cam top (rear curtain)
203c Cam opening (rear curtain)
203n cam inclined part (rear curtain)
203d Cam riding part (light-shielding curtain)
203e Cam tilted part (light-shielding curtain)
203f Cam top (light-shielding curtain)
203g Cam slope (light-shielding curtain)
203h Cam top (light-shielding curtain)
203i Cam opening (light-shielding curtain)
203j Gear fitting 203k Gear engagement 203l Phase plate fitting 203m Phase plate engagement 204a Charge roller (rear curtain)
204b Charge roller (shading curtain)
205 Auxiliary main plate (Mg main plate)
206 Cover plate 206a Aperture (opening)
206g, h Stopper 206j, k Stopper 207 Partition plate 208 Cam phase plate 208a Light-shielding part (cam phase plate)
208a Light-shielding part (cam phase plate)
209 Cam gear 209a Mating part 209b Engaging part 212 Rear curtain Armature 214 Coro cover 217a Photo sensor CN2
217b Photo sensor CHG
220 Motor 221 Gear 1 (Reduction gear)
222 gear 2 (reduction gear)
223 gear 3 (reduction gear)
224 gear 4 (reduction gear)
225 Motor gear Main plate 226 Gear cover 230 Rear blade group 231 1st blade 232 2nd blade 233 3rd blade 235 Main arm 235c Transmission part 236 Sub-arm 237 Blade backlash spring 238 Dowel 240 Ratchet 241 Rear blade drive spring 242 Elastic member 243 Buffer Member 243a Contact part 250 Electromagnet 251 York 252 Bobbin 253 Coil 254a Terminal 254b Terminal 255 Rear curtain lock lever 255a Hook part (rear curtain lock lever)
256 Shading curtain lock lever 256a Claw part (Shading curtain lock lever)
251 York 302 Light-shielding blade drive member 302a Drive pin 302b Fitting part 302c Drive shaft hole part 302d Contact part 302e Roller shaft 302f Contact part 302g Lock part 312 Armature (light-shielding)
330 Shading blade group 331 No. 1 blade (shading)
332 No. 2 blade (shading)
333 No. 3 blade (shading)
335 Main arm (shading)
336 Secondary arm (shading)
341 Light-shielding blade drive spring 350 Electromagnet (light-shielding)

Claims (4)

An opening forming member that forms an opening,
A cover member that forms a blade chamber between the opening forming member and
A group of blades that open and close the opening,
Two arms that rotatably connect and support the blade group,
It has a drive pin connected to the arm, and the drive pin is inserted into a hole provided in the cover member and rotates in parallel with the opening surface of the opening to open and close the blade group. Drive member and
A cushioning member attached on an extension of the rotation locus of the driving member in the hole and formed of a resin material, and a cushioning member.
An elastic member provided between the cushioning member and the inner wall of the hole on the extension of the rotation locus of the driving member and having elasticity more than the cushioning member is provided.
The cushioning member has at least one convex portion and a concave portion, and has at least one convex portion and a concave portion.
The convex portion is in contact with the cover member side recess provided in the cover member, the recess that makes contact with the cover member side protrusion provided on said cover member, said elastic member and contact with said bore It is attached to the part ,
The blade driving device is characterized in that the driving member is held in a state in which the driving pin is in contact with the cushioning member in a standby state. The blade driving device according to claim 1, wherein the cushioning member is housed within the plate thickness of the cover member. A focal plane shutter device comprising the blade driving device according to claim 1 or 2 as a shutter device. An imaging device characterized in that exposure adjustment is performed using the blade driving device according to claim 1 or 2.

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