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Digital Camera Patent Abstract
A digital camera, which an interchangeable lens system allowing
a plurality of lenses to be selectively and detachably attached
to a lens mount provided to a camera body, is configured such that
an object image is captured by an image sensor. The camera is provided
with a plurality of movable members which are arranged between the
lens mount and the image capturing area of the image sensor. The
plurality of movable members move when an image is captured. The
camera is further provided with an operable member allowing a user
to select one of a plurality of operation modes. The plurality of
operation modes include at least a cleaning mode. The movable members
are retracted from a path from the lens mount to the image sensor
to allow an access to the image sensor from the lens mount when
the cleaning mode is selected.
Digital Camera Patent Claims
What is claimed is:
1. A digital camera employing an interchangeable lens system allowing
a plurality of lenses to be selectively and detachably attached
to a lens mount provided to a camera body, the digital camera comprising:
an image sensor that captures an optical image of an object formed
by a lens attached to the camera body; a plurality of movable members
being arranged between the lens mount, the plurality of movable
members moving when an image is captured; an operable member allowing
a user to select one of a plurality of operation modes of the digital
camera, the plurality of operation modes including at least a cleaning
mode; and a controller that drives the movable members to be retracted
from a path from the lens mount to the image sensor to allow access
to the image sensor from the lens mount when the cleaning mode is
selected by the operable member.
2. The digital camera according to claim 1, wherein the digital
camera is a digital single-lens reflex camera; wherein the movable
members include a quick return mirror and a shutter; and wherein
the controller moves the quick return mirror to a lifted position
and maintains the shutter in an opened status when the cleaning
mode is selected.
3. The digital camera according to claim 1, wherein the camera
body is provided with electrodes that supply electrical power when
the cleaning mode is selected.
4. A cleaning apparatus that removes dirt and/or dust adhered to
an image capturing area of an image sensor arranged inside a camera
body, the camera body having a lens mount to which a plurality of
exchangeable lenses are selectively and detachably mounted, the
cleaning apparatus being detachably mounted to the lens mount, the
cleaning apparatus comprising: a cleaning head having a front end
surface that faces the image capturing area of the image sensor
when the cleaning apparatus is mounted on the lens mount; an opening
formed on the front end surface of the cleaning head; and an aspirator
pipe connected to the opening formed on the front end surface of
the cleaning head, the air being ejected from the camera body to
outside through the aspirator pipe.
5. The cleaning apparatus according to claim 4, further including
an aspirating apparatus that aspirates the air inside the camera
body through the aspirator pipe.
6. The cleaning apparatus according to claim 5, wherein the aspirating
apparatus is an electrically operable apparatus, an electrical power
being supplied to the aspirating apparatus from the camera body.
7. The cleaning apparatus according to claim 4, wherein the front
end surface faces the image capturing area of the image sensor with
a minute gap there between.
8. The cleaning apparatus according to claim 4, wherein the front
end surface has an area that is greater than the image capturing
area of the image sensor.
9. The cleaning apparatus according to claim 4, further including
a flange portion formed around the aspirator pipe, the flange portion
contacting the lens mount when the cleaning apparatus is coupled
to the camera body, the flange portion restricting an inserting
amount of the cleaning head in the camera body.
10. The cleaning apparatus according to claim 9, wherein the flange
portion is formed with at least one inlet opening that allows the
air to be introduced inside the camera body, the cleaning apparatus
including a filter that filters the air introduced from the at least
one inlet opening, the air filtered by the filter being introduced
in the camera body.
11. The cleaning apparatus according to claim 5, where the aspirating
apparatus is an non-electrically operable apparatus which is manually
operated by a user.
12. A digital camera system including a digital camera and a cleaning
apparatus, the digital camera employing an interchangeable lens
system allowing a plurality of lenses to be selectively and detachably
attached to a lens mount provided to a camera body, wherein the
digital camera comprises: an image sensor that captures an optical
image of an object formed by the lens attached to the camera body;
a plurality of movable members being arranged between the lens mount,
the plurality of movable members moving when an image is captured;
an operable member allowing a user to select one of a plurality
of operation modes of the digital camera, the plurality of operation
modes including at least a cleaning mode; and a controller that
drives the movable member to be retracted from a path from the lens
mount to the image sensor to allow an access to the image sensor
from the lens mount when the cleaning mode is selected by the operable
member, and wherein the cleaning apparatus comprises: a mounting
mechanism that allows the cleaning apparatus to be mounted on the
lens mount; a cleaning head having a front end surface that faces
the image capturing area of the image sensor when the cleaning apparatus
is mounted on the lens mount; an opening formed on the front end
surface of the cleaning head; and an aspirator pipe connected to
the opening formed on the front end surface of the cleaning head,
the air being ejected from the camera body to outside through the
aspirator pipe.
13. The camera system according to claim 12, wherein the cleaning
apparatus further includes an aspirating apparatus that aspirates
the air inside the camera body through the aspirator pipe.
14. The camera system according to claim 13, wherein the aspirating
apparatus is an electrically operable apparatus, wherein the camera
body is provided with first electrodes that supply electrical power
when the cleaning mode is selected, wherein the aspirating apparatus
is provided with second electrodes which contact the electrodes
provided to the camera body when the cleaning apparatus is mounted
on the camera body, an electrical power being supplied to the aspirating
apparatus from the camera body through the first and second electrodes.
15. The camera system according to claim 13, where the aspirating
apparatus is an non-electrically operable apparatus which is manually
operated by a user.
16. The camera system according to claim 12, wherein the front
end surface faces the image capturing area of the image sensor with
a minute gap there between.
17. The camera system according to claim 12, wherein the front
end surface has an area that is greater than the image capturing
area of the image sensor.
18. The cleaning apparatus according to claim 12, the cleaning
apparatus including a flange portion formed around the aspirator
pipe, the flange portion contacting the lens mount when the cleaning
apparatus is coupled to the camera body, the flange portion restricting
an inserting amount of the cleaning head in the camera body.
19. The camera system according to claim 18, wherein the flange
portion is formed with at least one inlet opening that allows the
air to be introduced inside the camera body, the cleaning apparatus
including a filter that filters the air introduced from the at least
one inlet opening, the air filtered by the filter being introduced
in the camera body.
Digital Camera Patent Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a digital camera employing
an exchangeable lens system, such as a digital SLR (single-lens
reflex) camera, and particularly to a structure and/or apparatus
for removing dust or minute particles invaded inside a body of such
a digital camera.
[0002] A digital SLR camera is configured such that various types
of lenses can be exchangeably attached to a camera body. For this
purpose, a lens mount is formed on the camera body. When a lens
is detached from the camera body (i.e., the lens mount), the interior
of the camera body is exposed to the open air through an opening
of the lens mount, and dirt and/or dust may readily enter the camera
body through the opening. The dirt and/or dust entered through the
opening typically adheres onto a quick return mirror (i.e., a movable
mirror) and/or a focusing glass. Such dirt and/or dust can easily
be removed with a device such as a blower, which is inserted through
the opening of the lens mount. However, some portion of the dust
passes through a shutter that opens at the time of release, and
adheres to an image capturing area of an image sensor such as a
CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide
Semiconductor). The dirt and/or dust interferes with the image of
the object in reaching to the image sensor, and causes partial lack
of image represented by the image signals, which is output by the
image sensor. With regard to general digital cameras, an image sensor
is often configured as a unit where its image capturing area is
protected by a cover glass. Even in such a case, the above-described
problem may occur. Therefore, in the specification, a term "an
image capturing area of an image sensor" includes an image
capturing unit which is defined as an image sensor provided with
the cover glass in front of the image capturing area thereof.
[0003] In order to prevent the partial lack of images caused by
the dirt and/or dust adhered to the image capturing area of the
image sensor, various methods/structures have been suggested. An
example of a dust-proof structure is disclosed in Japanese Patent
Publication No. 3520914. The publication discloses a dust-protective
casing that prevents dirt and/or dust from adhering to the image
capturing area of the image sensor. A wall in front of the image
capturing area of the image sensor is located at a defocused position
so that the dirt and/or dust adhered on the dust-protective casing
does not substantially cause the lack of part of the image on the
image capturing area.
[0004] Another example of the dust-proof structure is disclosed
in United States Patent Application Publication No. 2004/0047625
A1, the teachings of which are incorporated herein by reference.
According to this publication, a dust-proof optical member is provided
in front of the image capturing area of the image sensor, and a
mechanism that vibrates the dust-proof optical member is implemented
in order to remove the dirt and/or dust adhered on the dust-proof
optical member.
[0005] The configuration described in Japanese Patent Publication
No. 3520914 is rather effective when the amount or the size of the
dirt and/or dust adhered to the dust-protective casing is sufficiently
small. When the amount of the size is larger, however, the dirt
and/or dust blocks light that forms an image on the image sensor,
and its effect is not negligible. Furthermore, the publication does
not provide fundamental measures to remove the dirt and/or dust
invaded inside the camera body.
[0006] Regarding the art described in United States Patent Application
Publication No. 2004/0047625 A1, the effectiveness of removing the
dirt and/or dust is assumed to depend on the degree of vibration
of the dust-protective optical member. If the amplitude is small,
the effectiveness is assumed to be small, while the vibration is
propagated to the entire camera and causes awkwardness if the amplitude
is set too large. In addition, the publication does not disclose
removing the dirt and/or dust that has penetrated inside the camera
body, either. Therefore, according to this publication, the dirt
and/or dust which is effectively prevented from adhering to the
dust-protective optical member or effectively removed from the dust-protective
optical member still remains inside the camera body. No fundamental
cleaning measure is presented in the publication.
SUMMARY OF THE INVENTION
[0007] The present invention is advantageous in that a digital
camera and its cleaning apparatus are provided, with which the dirt
and/or dust adhered to the image capturing area of the image sensor
can be effectively removed therefrom and ejected outside the camera
body.
[0008] According to an aspect of the present invention, there is
provided a digital camera employing an interchangeable lens system
allowing a plurality of lenses to be selectively and detachably
attached to a lens mount provided to a camera body. The digital
camera includes an image sensor that captures an optical image of
an object formed by the lens attached to the camera body, a plurality
of movable members being arranged between the lens mount, the plurality
of movable members moving when an image is captured, an operable
member allowing a user to select one of a plurality of operation
modes of the digital camera, the plurality of operation modes including
at least a cleaning mode, and a controller that drives the movable
members to be retracted from a path from the lens mount to the image
sensor to allow an access to the image sensor from the lens mount
when the cleaning mode is selected by the operable member.
[0009] Optionally, the digital camera may be a digital single-lens
reflex camera, and the movable members include a quick return mirror
and a shutter. The controller automatically moves the quick return
mirror to a lift-up position and maintains the shutter in an opened
status when the cleaning mode is selected.
[0010] Further optionally, the camera body may be provided with
electrodes that supply electrical power when the cleaning mode is
selected.
[0011] According to another aspect of the invention, there is provided
a cleaning apparatus that removes dirt and/or dust adhered to an
image capturing area of an image sensor arranged inside a camera
body, the camera body having a lens mount to which a plurality of
exchangeable lenses are selectively and detachably mounted, the
cleaning apparatus being detachably mounted on the lens mount, the
cleaning apparatus is provided with a cleaning head having a front
end surface that faces the image capturing area of the image sensor
when the cleaning apparatus is mounted on the lens mount, an opening
formed on the front end surface of the cleaning head, and an aspirator
pipe connected to the opening formed on the front end surface of
the cleaning head, the air being ejected from the camera body to
outside through the aspirator pipe.
[0012] Optionally, the cleaning apparatus may further include an
aspirating apparatus that aspirates the air inside the camera body
through the aspirator pipe.
[0013] In a particular case, the aspirating apparatus may be an
electrically operable apparatus, an electrical power being supplied
to the aspirating apparatus from the camera body. Alternatively,
the aspirating apparatus can be a non-electrically operable apparatus
which is manually operated by a user.
[0014] Optionally, the front end surface may face the image capturing
area of the image sensor with a minute gap there between.
[0015] Still optionally, the front end surface may have an area
that is greater than the image capturing area of the image sensor.
[0016] Further optionally, the cleaning apparatus may further include
a flange portion formed around the aspirator pipe, the flange portion
contacting the lens mount when the cleaning apparatus is coupled
to the camera body, the flange portion restricting an inserting
amount of the cleaning head in the camera body.
[0017] The flange portion may be formed with at least one inlet
opening that allows the air to be introduced inside the camera body,
the cleaning apparatus including a filter that filters the air introduced
from the at least one inlet opening, the air filtered by the filter
being introduced in the camera body.
[0018] According to a further aspect of the invention, there is
provided a digital camera system including a digital camera and
a cleaning apparatus, the digital camera employing an interchangeable
lens system allowing a plurality of lenses to be selectively and
detachably attached to a lens mount provided to a camera body. The
digital camera may include an image sensor that captures an optical
image of an object formed by the lens attached to the camera body,
a plurality of movable members being arranged between the lens mount,
the plurality of movable members moving when an image is captured,
an operable member allowing a user to select one of a plurality
of operation modes of the digital camera, the plurality of operation
modes including at least a cleaning mode, and a controller that
drives the movable member to be retracted from a path from the lens
mount to the image sensor to allow an access to the image sensor
from the lens mount when the cleaning mode is selected by the operable
member. Further, the cleaning apparatus includes a mounting mechanism
that allows the cleaning apparatus to be mounted on the lens mount,
a cleaning head having a front end surface that faces the image
capturing area of the image sensor when the cleaning apparatus is
mounted on the lens mount, an opening formed on the front end surface
of the cleaning head, and an aspirator pipe connected to the opening
formed on the front end surface of the cleaning head, the air being
ejected from the camera body to outside through the aspirator pipe.
[0019] Optionally, the cleaning apparatus may further include an
aspirating apparatus that aspirates the air inside the camera body
through the aspirator pipe.
[0020] In a particular case, the aspirating apparatus is an electrically
operable apparatus. In such a case, the camera body may be provided
with first electrodes that supply electrical power when the cleaning
mode is selected, while the aspirating apparatus may be provided
with second electrodes which contact the electrodes provided to
the camera body when the cleaning apparatus is mounted on the camera
body, an electrical power being supplied to the aspirating apparatus
from the camera body through the first and second electrodes.
[0021] Alternatively, the aspirating apparatus may be an non-electrically
operable apparatus which is manually operated by a user.
[0022] Optionally, the front end surface may be positioned to face
the image capturing area of the image sensor with a minute gap therebetween.
[0023] Further optionally, the front end surface may have an area
that is greater than the image capturing area of the image sensor.
[0024] Still optionally, the cleaning apparatus may include a flange
portion formed around the aspirator pipe, the flange portion contacting
the lens mount when the cleaning apparatus is coupled to the camera
body, the flange portion restricting an inserting amount of the
cleaning head in the camera body.
[0025] Optionally, the flange portion may be formed with at least
one inlet opening that allows the air to be introduced inside the
camera body, the cleaning apparatus including a filter that filters
the air introduced from the at least one inlet opening, the air
filtered by the filter being introduced in the camera body.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[0026] FIG. 1 is a perspective view of a camera body of a digital
camera according to the present invention;
[0027] FIG. 2 is a cross-sectional side view of the camera body
shown in FIG. 1;
[0028] FIG. 3 is a perspective view of a cleaning apparatus according
to a first embodiment of the invention;
[0029] FIG. 4A is a cross-sectional side view of the cleaning apparatus
shown in FIG. 3;
[0030] FIG. 4B is a cross-sectional view of the cleaning apparatus
taken along line B-B in FIG. 4A;
[0031] FIG. 5 is a cross-sectional side view of the camera body
to which the cleaning apparatus according to the first embodiment
is attached;
[0032] FIG. 6 is a perspective view of a cleaning apparatus according
to a second embodiment of the invention;
[0033] FIG. 7 is a cross-sectional side view of the camera body
to which the cleaning apparatus according to the second embodiment
is attached;
[0034] FIG. 8 shows a cross-sectional side view of an injection
type aspiration apparatus to be used together with the cleaning
apparatus according to the second embodiment; and
[0035] FIG. 9 shows a cross-sectional side view of a blower type
aspiration apparatus to be used together with the cleaning apparatus
according to the second embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENT
[0036] Referring to the accompanying drawings, first and second
embodiments of the present invention will be described.
First Embodiment
[0037] FIG. 1 shows an external view of a digital SLR camera 100
employing an interchangeable lens system, in accordance with an
exemplary embodiment of this invention. On a front surface of a
camera body 1, a lens mount 2 is provided. Via the lens mount 2,
various interchangeable lenses (not shown) can be detachably attached
to the camera body 1. In FIG. 1, Ox denotes an optical axis of the
camera 100. The optical axis Ox is defined as an axis which coincides
with an optical axis of the lens attached to the camera body 1.
FIG. 2 shows a diagrammatic cross-sectional side view taken along
the optical axis Ox of the camera 100. In the camera body 1, a mirror
box 3 is defined. Inside the mirror box 3 is provided a movable
mirror 4 that reciprocates in up-and-down direction, a focusing
glass 5, and a shutter 6 are provided adjacently. The mirror box
3 is, as shown in FIGS. 1 and 2, exposed to outside through an opening
defined by (i.e., surrounded by) the lens mount 2 when the lens
is not attached to the camera body 1. Above the focusing glass 5,
a finder optical system 7 including a pentaprism 7a and an eyepiece
lens 7b is provided. Behind the shutter 6 (on a left-hand side of
the shutter 6 in FIG. 2), an image sensing unit 8 is provided. The
image sensing unit 8 captures an object image formed through a lens
attached to the camera body 1, and outputs an image signal representing
the captured image. The image sensing unit 8 contains an image sensor
8a which is comprised of a photoelectric converter, such as CCD
or CMOS, in a package 8b. The image sensing unit 8a is enclosed
by a cover glass 8c, which is arranged in front of the image capturing
area of the image sensor 8a. In this digital SLR camera 100, when
a shutter release operation is not being carried out, the movable
mirror 4 is located at the lower position as drawn in solid lines,
the shutter 6 is closed, and light passed through the lens is reflected
in the mirror 4 and forms an image on the focusing glass 5, which
image can be observed through the finder optical system 7. When
the shutter release operation is being carried out, the movable
mirror 4 is located at an uplifted position as drawn with double-dashed
lines, the shutter 6 is opened, and light provided through the lens
is incident on the image capturing area of the image sensor 8a inside
the image sensing unit 8 to form the object image thereon. The image
sensor 8a outputs photoelectrically converted image signals corresponding
to the object image.
[0038] As shown in FIG. 1, at the top surface of the camera body
1, a release button 9 for the release operation described above
and a mode dial 10 to switch among a plurality of operation modes
are provided. In the camera 100 according to the embodiment, a cleaning
mode is included in the plurality of operation modes. The cleaning
mode is selected when the dirt and/or dust inside the camera body
1 is to be removed. The mode dial 10 is connected with an electrical
circuit, which has a well-known configuration and description thereof
is herein omitted. When the mode dial 10 is set to the cleaning
mode, the movable mirror 4 is moved to the uplifted position, and
the shutter 6 is opened. When the mode dial 10 is switched to another
mode from the cleaning mode, the movable mirror 4 returns to the
lower position, and the shutter 6 is closed. Inside the camera body
1, two cleaning electrode terminals 12 are provided. The cleaning
electrode terminals 12 are used for supplying a prescribed voltage
to a cleaning apparatus 20 (described later) when it is coupled
to the camera body 1. The voltage output by the cleaning electrode
terminals 12 is supplied by a battery (not shown) that is contained
inside the camera body 1.
[0039] FIG. 3 is an external perspective view of the cleaning apparatus
to be used in association with the digital SLR camera 100. FIG.
4A is a cross-sectional side view of the cleaning apparatus 20 taken
along the central axis of the cleaning apparatus, and FIG. 4B is
a cross-sectional view taken along line B-B of FIG. 4A. The cleaning
apparatus 20 is configured to remove the dirt and/or dust adhered
to the surface of cover glass 8c of the image sensing unit 8. The
cleaning apparatus 20 is inserted inside the camera body 1 through
the opening at the lens mount 2, and is equipped with an aspirator
pipe 21 that allows air to flow therein, and an aspirator module
22 that is positioned behind the aspirator pipe 21. The aspirator
pipe 21 is integrated with a rectangular head 23, which is inserted
through an opening of the shutter 6 when the shutter 6 is opened
and positioned to face the cover glass 8c of the image sensing unit
8. The rectangular head 23 is formed at least greater than the image
capturing area of the image sensor 8a in shape and size, and a front
end surface 23a thereof is flattened. The center of the front end
surface 23a is provided with a circular aspirator opening 24, which
communicates with the inside of the aspirator pipe 21. Further,
at a base of the aspirator pipe 21, a circular flange 25 that directly
abuts a mounting surface of the lens mount 2 is integrally formed.
It is preferable the flange 25 is configured to be fixedly coupled
to the lens mount 2. In the present embodiment, the flange 25 is
provided with a bayonet piece 25a, which is similar to those provided
to the interchangeable lenses, and the flange 25 is configured to
be interlocked fixedly to the lens mount 2 by rotating the flange
25 by a small angle to engage the bayonet piece 25a with a bayonet
groove formed on the lens mount 2.
[0040] When the rectangular head 23 of the aspirator pipe 21 is
inserted into the camera body 1 through the opening of the lens
mount 2, and the flange 25 is abutted onto the lens mount 2, the
rectangular head 23 passes through the opened shutter 6 and is positioned
such that the front end surface 23a faces the cover glass 8c. The
length of the aspirator pipe 21 is designed to maintain a minute
gap d between the front surface 23a and the cover glass 8c. The
opening of the shutter 6 is formed to have a sufficient space that
allows the rectangular head 23 to rotate together with the integrated
aspirator pipe 21 when the flange 25 is coupled to the lens mount
2 by the bayonet piece 25a. Alternatively, the rectangular head
23 may be rotatably connected to the aspirator pipe 21 so that the
flange 25 can be rotated when interlocked to the lens mount 2 with
allowing the rectangular head 23 to be substantially fitted in the
opening of the shutter 6.
[0041] The aspirator module 22 of the cleaning apparatus 20 is
equipped with a turbo fan 26, which is integrated with the flange
25 at the proximal end of the aspirator pipe 21, and a motor 27
that drives the turbo fan 26. The turbo fan 26 has a fan room 26a,
which is a cylindrical hollow space and communicates with the inside
of the aspirator pipe 21, and rotary impeller 26b, which is installed
on a rotary shaft 27a of the motor 27 and driven thereby. When the
rotary impeller 26b is rotated, the air inside both the fan room
26a and the aspirator pipe 21 is ejected through exhaust outlets
26c, which are opened along the circumference of the fan room 26a.
[0042] The flange 25 is provided with, on the inner circumferential
surface of the lens mount 2, two electrode pins 28, which are supported
by springs 28a, respectively, and retractably protruded in the direction
of the axis of the aspirator pipe 21, toward the shutter 6. When
the flange 25 is mounted onto the lens mount 2, the electrode pins
28 resiliently contact the cleaning electrode terminals 12 provided
in the camera body 1, respectively, and connected thereto electrically.
The electrode pins 28 are electrically connected to the motor 27
through electric cords 28b, and a predetermined voltage is supplied
to the motor 27 through the cleaning electrode terminals 12. The
flange 25 is formed with a plurality of aspiration inlets 25b which
are through openings penetrating the flange 25 in the thickness
direction at positions along the outer diameter of the aspirator
pipe 21. The plurality of aspiration inlets 25b make the inside
of the camera body 1 communicate with the outside thereof when the
flange 25 contacts the lens mount 2. Between the flange 25 and the
fan room 26a of the turbo fan 26, an annular filter 29 is provided
to filter the dirt and/or dust in the air that passes through the
aspiration inlets 25b.
[0043] A method of cleaning the image sensing unit 8 inside the
camera body 1 by use of the cleaning apparatus 20 configured as
above will be described. FIG. 5 shows a cross-sectional side view
of the cleaning apparatus 20 in use. When a lens (not shown) is
removed from the camera body 1 and mode dial 10 is switched to the
cleaning mode, the movable mirror 4 is moved to the uplifted position,
while the shutter 6 is opened, and the cover glass 8c of the image
sensing unit 8 behind the mirror box 3 is exposed. Further, the
aspirator pipe 21 with the rectangular head 23 of the cleaning apparatus
20 is inserted into the camera body 1 through the opening of the
lens mount 2. The flange 25 is positioned to the lens mount 2 and
rotated by a predetermined small angle about the pipe axis. Then,
the flange 25 is fixedly interlocked to the lens mount 2 by the
bayonet piece 25a that is provided to the flange 25. When the cleaning
apparatus 20 is coupled to the camera body 1 as above, the rectangular
head 23 at the end of the aspirator pipe 21 is inserted through
the mirror box 3 and the shutter 6, and its front end surface 23a
is positioned to face the surface of the cover glass 8a of the image
sensing unit 8 with a minute gap d therebetween. When the flange
is rotated by a small angular amount for attachment, the rectangular
head 23 is also rotated by the small angular amount. However, as
described above, the allowance provided at the shutter 6 (or, in
the alternative embodiment, the configuration that only the flange
25 is rotatable), the rectangular head 23 is located at the predetermined
position in a predetermined orientation.
[0044] When the cleaning apparatus 20 is coupled to the camera
body 1 as described above, the electrode pins 28 provided on the
inner surface of the flange 25 resiliently and electrically contact
the cleaning electrode terminals 12 provided on the outer surface
of the lens mount 2. Thus, the predetermined voltage, which is supplied
from the battery when the mode dial 10 is switched to the cleaning
mode, is supplied from the cleaning electrode terminals 12 to the
motor 27 through the electrode pins 28 and the electric cords 28b.
With the voltage supplied, the motor 27 rotates, and ejects the
air inside the fan room 26a through the exhaust outlets 26c as illustrated
in dashed arrows. This evacuating operation generates negative pressure
inside the aspirator pipe 21, and the air inside the camera body
1 is aspirated and ejected outside the camera body 1 as described
above. In addition, inside the camera body 1 the outside air is
aspirated through the aspiration inlets 25b, which is purified through
the filter 29. This series of evacuating operation generates a centralizing
air flow, on the cover glass 8c, from the periphery toward the center
at the gap d between the rectangular head 23 and the front end surface
23a. The venturi effect caused by this air flow remarkably speeds
up the current. The air flow unsticks and removes the dirt and/or
dust adhered to the surface of the cover glass 8c, and thus the
surface of the cover glass 8c is cleaned. The air flow also ejects
the dirt and/or dust floating inside the camera body 1.
[0045] After the cleaning is accomplished, when the cleaning apparatus
20 is detached from the camera body 1 and the mode dial 10 is switched
from the cleaning mode to another mode, the shutter 6 is closed,
and the movable mirror 4 is returned to the lower position. When
the movable mirror 4 is located at the lower position, the interior
of the mirror box 3 is still exposed to outside through the opening
of the lens mount 2. However, the surface of the cover glass 8c
is blocked by the shutter 6, and therefore separated from the interior
of the mirror box 3. This configuration prevents additional dirt
and/or dust from adhering to the surface of the cover glass 8c.
[0046] In the embodiment described above, the movable mirror 4
is moved to the uplifted position and the shutter 6 is opened when
the camera 100 operates in the cleaning mode. It is possible that
the cleaning mode may be substituted by the "bulb" setting
of the shutter speed. In the bulb setting, the movable mirror 4
is uplifted and the shutter 6 is opened while the release button
9 is being depressed. In this case, however, the release button
9 must remain depressed during the cleaning. In regard to this inconvenience,
configuring the cleaning mode as described above suggests a more
effortless method of cleaning without requiring continuous depression
of the release button 9.
[0047] In the above embodiment, since the motor 27 is used for
aspirating, it is possible that the cleaning apparatus 20 generates
a high-speed continuous air current so that the dirt and/or dust
is effectively removed. In addition, the cleaning apparatus 20 is
not required to be equipped with a dedicated independent battery,
as the motor 27 utilizes the battery built in the camera body 1,
and therefore the cleaning apparatus 20 may remain downsized. Further,
the cleaning operation does not produce vibration in the camera
100, and therefore the awkwardness caused by the vibration is avoided.
Also, the cleaning operation is performed without contacting the
cleaning device 20 with the surface of the cover glass 8c, and therefore,
the cover glass 8c will not be damaged by the cleaning device 20.
Second Embodiment
[0048] FIG. 6 is a perspective view showing an appearance of a
cleaning apparatus 20A according to a second embodiment, and FIG.
7 is a cross-sectional view of the cleaning apparatus 20A in use.
In this embodiment, the cleaning apparatus 20A is configured to
remove the dirt and/or dust adhered to the cover glass 8c of the
image sensing unit 8 by manually aspirating the air inside the camera
body 1. It should be noted that the cleaning apparatus 20A has a
simplified configuration compared to the cleaning device 20 according
to the first embodiment. In FIG. 6 and FIG. 7, the components equivalent
to those shown in the first embodiment are assigned with the identical
reference numerals as in the first embodiment. In this embodiment,
a rectangular head 23 is provided at the end of an aspirator pipe
21, and the apical area 23a is provided with a circular aspiration
opening 24 that communicates with the inside of the aspirator pipe
21. Further, the base of the aspirator pipe 21 is provided with
a flange 25. Similar to the first embodiment, the flange 25 is formed
with bayonet piece 25a and aspiration inlets 25b, and equipped with
a filter 29. In the second embodiment, at the base of the aspirator
pipe 21, only a hollow cylindrical aspirator tube 21A is integrally
formed, and an aspiration apparatus is provided separately. As described
below, a manually operable aspiration apparatus is configured to
be connected with the aspirator tube 21A.
[0049] A manually operable (non-electric) aspiration apparatus
that is connected to the aspirator tube 21A may be, for example,
a pump aspirator 30 as illustrated in FIG. 8. Like a syringe, the
pump aspirator 30 contains a plunger 32, which is reciprocative
in the axial direction, inside the outer tube 31 formed with an
aspirating opening 31a. The air is aspirated inside the outer tube
31 when the plunger 32 is pulled out (i.e., moved to a left-hand
side in FIG. 8) with respect to the outer tube 31. The pump aspirator
30 is equipped with a spring 33 that applies an expanding force
to move the plunger 32 in a direction away from the aspirating opening
31a. Further, the pump apparatus 30 is provided with a latch 34
that clasps the plunger 32 to prevent the plunger 32 from sliding
out unexpectedly. As the pump aspirator, a desolder pump that is
used for removing excess solder may be utilized.
[0050] The pump aspirator 30 is connected directly or through a
flexible member such as a rubber tube to the aspirator tube 21A
of the cleaning apparatus 20. As illustrated in FIG. 7, by setting
the camera body 1 in the cleaning mode, the movable mirror 4 is
moved to the uplifted position and the shutter 6 is opened. The
aspirator pipe 21 is inserted into the camera body 1. In this event,
the flange 25 is fixedly interlocked to the lens mount 2 preferably
utilizing the bayonet piece 25a, and the rectangular head 23 is
positioned to face the surface of the cover glass 8c of the image
sensing unit 8 with a slight gap d therebetween. Furthermore, when
the plunger 32 becomes free by releasing the latch 34, the plunger
32 slides outward by the force applied by the spring 33, and the
air is aspirated through the opening 31a. Through this operation,
similarly to the first embodiment, the air inside the camera body
1 is ejected through the aspirator pipe 21 of the cleaning apparatus
20A, and thus due to the air current generated at the gap d between
the front end surface 23a of the rectangular head 23 and the cover
glass 8c, the dirt and/or dust adhered to the cover glass 8c is
removed.
[0051] Alternatively, as another manual aspiration measure, a blower
aspirator 40 as illustrated in FIG. 9 may be used. The blower aspirator
40 is configured with an air pump 41 formed from rubber or flexible
plastic and a pipe 42 provided at an opening of the air pump 41.
The air pump 41 may be compressed by hand, and may return to the
initial shape by its own elasticity, which causes the air inside
to discharge and the ambient air to enter. The pipe 42 is provided
with a diverging outlet 43, and an exhaust valve 45 is provided
inside the diverging outlet 43. The exhaust valve 45 only allows
the air in the blower aspirator 40 to discharge. Also, an aspirator
valve 44 is provided inside the pipe 42, which only allows the air
to be aspired from the ambient.
[0052] The blower aspirator 40 is connected directly or through
a flexible member such as rubber tube to aspirator tube 21 of the
cleaning apparatus 20. As illustrated in FIG. 7, by setting the
camera body 100 in the cleaning mode, the movable mirror 4 is uplifted
and the shutter 6 is opened. The rectangular head 23 is inserted
into the camera body 1. In this event, the aspirator pipe 21 is
configured to rotate on the axis apart from the rectangular head
23, as this configuration allows the rectangular head 23 to be located
in the predetermined position, as described in the first embodiment.
In accordance with the above configuration, the air pump 41 is compressed
to eject the air inside the air pump 41 through the diverging outlet
43, and is successively released to return in the initial shape,
thereby the ambient air flows into the air pump 41 through the tube
42. This flow causes aspiration of the air inside the camera body
1 through the aspirator pipe 21 of the cleaning apparatus 21A. In
the camera body 1, the air current generated at the gap d between
the front end surface 23a of the rectangular head 23 and the surface
of the cover glass 8c removes the dirt and/or dust adhered to the
cover glass 8c.
[0053] In the second embodiment, the aspiration of the cleaning
apparatus 20A to eject/inject the air from/in the camera body 1
is operated manually (i.e., non-electrically), therefore a motor
or electric cords and electrodes to drive a motor are unnecessary,
and this allows the cleaning apparatus downsized and downscaled
in price. In addition, the camera body 1 is not required to be equipped
with the cleaning electrode terminals 12, in case the camera 100
is dedicated to the cleaning apparatus according to the second embodiment.
[0054] In the cleaning apparatus according to each embodiment,
the rectangular head 23 is provided with one circular aspirator
opening 24 that communicates with the aspirator pipe 21. It should
be noted, however, that more than one aspirator opening may be provided
at balanced points of the front end surface facing the cover glass
8c of the image sensing unit 8, where each opening communicates
with the inside of the aspirator pipe 21. It is preferable that
the locations of these openings are adjusted considering and calculating
the speed of the air current generated between the cover glass 8c
and the rectangular head 23 in regard to the aspirating capability.
[0055] In each embodiment described above, the bayonet piece 25a
is provided to the flange 25 of the cleaning apparatus in order
to attach the cleaning apparatus fixedly to the camera body 1. However,
cleaning may be performed sufficiently by pressing the flange 25
of the cleaning apparatus closely onto the lens mount 2, and thus
the configuration of the cleaning apparatus becomes even more simplified.
[0056] In addition, in the first embodiment, the cleaning electrode
terminals 12 are equipped in the camera body 1 to supply power to
the cleaning apparatus, however, existing lens information contacts
2a (refer to FIG. 1) that are provided on the lens mount 2 to exchange
information electrically between the camera body and the lens may
be utilized for power supply.
[0057] The present disclosure relates to the subject matter contained
in Japanese Patent Application No. 2004-172043, filed on Jun. 10,
2004, which is expressly incorporated herein by reference in its
entirety. |