TITLE OF THE INVENTION
ELECTRIC DEVICE
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electric device including a cover
which can open and close an opening formed in a casing.
2. Description of the Related Art
An electric device includes an opening which is formed for various
purposes in a casing forming an external appearance of the electric device.
There is known an electric device including a cover for covering the opening of
the casing when the opening is not used.
For example, in a video doorphone described in JP 2002-281489 A, a
unit housing part for housing a video recording unit is provided in a casing.
The video doorphone includes a cover that is fitted to the unit housing part to
cover an opening of the unit housing part when the video recording unit is not
accommodated therein and hence the video doorphone is not used for video
recording.
Like the cover described in JP 2002-281489 A, a cover of a conventional
electric device, which is used when the opening of the casing is not used, is
generally opened and closed through attachment and detachment. When the
opening is used, such cover is separated from the casing, and hence the cover is

sometimes damaged or lost.
SUMMARY OF THE INVENTION
In view of the above-mentioned problem, an object of the present
invention is therefore to provide an electric device including a cover which can
open and close an opening formed in a casing, can be easily attached to/detached
from the casing, and which can be received in the casing when opening the
opening.
According to the present invention, an electric device includes:
a casing including an opening portion formed in a peripheral wall
thereof; and
a cover including a lid portion for opening and closing the opening
portion, wherein:
the cover further includes a first bent portion and a second bent
portion which are provided in series to be continuous with the lid portion;
the casing includes:
a hole allowing the cover to be inserted/removed
into/from the casing therethrough and to be movable in its insertion/removal
direction, the hole being provided in a vicinity of the opening portion; and
a cover locking portion to which the cover is locked in a
substantially upright posture while covering the opening portion with the lid
portion thereof, the cover locking portion being provided around the opening
portion; and

the cover is pivotable in a fore-and-aft direction at a corner
portion on an inner side of the first bent portion of the cover with an inner edge
portion at an intersection between an upper inner wall surface of the hole and an
inner wall surface of a front wall as a fulcrum, and the cover is allowed to be
displaced between the substantially upright posture and a substantially laid
posture.
Further, according to the present invention, in the electric device, the
first bent portion and the second bent portion are respectively formed into
substantially L-shapes, and the first bent portion and the second bent portion are
continuously formed into a step shape.
Further, according to the present invention, in the electric device, a
corner portion on an inner side of the second bent portion is engaged with an
inner edge portion located at an intersection between a lower inner wall surface
of the hole and the inner wall surface of the front wall.
Further, according to the present invention, in the electric device, the
cover locking portion includes a recess formed to allow an outer surface of the
cover to be flush with an outer surface of the peripheral wall of the casing when
the cover takes the substantially upright posture.
Further, according to the present invention, in the electric device, the
cover is made of metal, and the cover locking portion includes a magnet to
which the cover is attracted so that the cover is kept in the substantially upright
posture.
Further, according to the present invention, in the electric device, the
casing includes a cover receiving portion in which the cover is received in the

substantially laid posture, the cover receiving portion being provided on an inner
side of the hole.
Further, according to the present invention, in the electric device, the
cover receiving portion includes a biasing member for biasing movement of the
cover to an outside of the casing.
In the present invention, the cover is allowed to be inserted/removed
through the hole, that is, to be attached to/detached from the casing. Further,
the cover is pivotable in a fore-and-aft direction at the corner portion on the
inner side of the first bent portion of the cover with the inner edge portion at the
intersection between the upper inner wall surface of the hole and the inner wall
surface of the front wall as the fulcrum. The cover is displaced between the
substantially upright posture and the substantially laid posture, and can open and
close the opening portion. Further, in the substantially laid posture, that is, in a
state of opening the opening portion, the cover can be received in the cover
receiving portion of the casing. In addition, the corner portion on the inner side
of the second bent portion is engaged with the inner edge portion located at the
intersection between the lower inner wall surface of the hole and the front-wall
inner wall surface, and hence it is possible to prevent the cover from rattling in
an up-down direction in the cover receiving portion.
Therefore, according to the present invention, it is possible to obtain an
electric device in which a cover for opening and closing an opening portion can
be attached to/detached from a casing, and in which the cover can be received in
the casing when opening the opening portion.

BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a perspective view of a fire detector as an example of an
electric device according to a first embodiment of the present invention, which
illustrates a state in which a cover closes an opening portion while taking a
substantially upright posture;
FIG. 2 is a perspective view of the fire detector, which illustrates a state
in which the cover opens the opening portion and is received in an inside of a
casing while taking a substantially laid posture;
FIGS. 3A to 3C are views of the fire detector in a state illustrated in FIG
1, in which FIG. 3A is a partially-omitted front view of the fire detector, FIG. 3B
is a sectional view taken along the line A-A of FIG. 3A, and FIG. 3C is an
enlarged view of the part B of FIG. 3B;
FIGS. 4A to 4C are views of the fire detector in a state illustrated in FIG.
2, in which FIG. 4A is a partially-omitted front view of the fire detector, FIG. 4B
is a sectional view taken along the line A-A of FIG. 4A, and FIG. 4C is an
enlarged view of the part B of FIG. 4B;
FIG. 5 is a perspective view of the cover of the fire detector;
FIG. 6 is a perspective vertical sectional view of a main part of the fire
detector, which illustrates a state in which the cover is attached from a back
surface of the casing and not locked to a hook;
FIGS. 7A to 7C are views of the fire detector in a state in which the
cover is pulled to an outside of the casing and is in the course of pivoting

between the substantially laid posture and the substantially upright posture, in
which FIG. 7A is a partially-omitted front view of the fire detector, FIG. 7B is a
sectional view taken along the line A-A of FIG. 7A, and FIG. 7C is an enlarged
view of the part B of FIG. 7B;
FIGS. 8A to 8C are views of a fire detector according to a second
embodiment, which correspond to FIGS. 3A to 3C, and in which FIG. 8A is a
partially-omitted front view of the fire detector, FIG. 8B is a sectional view
taken along the line C-C of FIG. 8A, and FIG. 8C is an enlarged view of the part
D of FIG. 8B;
FIGS. 9A to 9C are views of the fire detector according to the second
embodiment, which correspond to FIGS. 4A to 4C, and in which FIG. 9A is a
partially-omitted front view of the fire detector, FIG. 9B is a sectional view
taken along the line A-A of FIG. 9A, and FIG. 9C is an enlarged view of the part
B of FIG. 9B;and
FIG. 10 is a perspective vertical sectional view of a main part of the fire
detector according to the second embodiment, which illustrates a state in which
the cover is further moved to the inside of the casing from a state illustrated in
FIGS. 9Ato 9C and is locked to a biasing member.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Description is made of cases in which embodiments of the present
invention are applied to a smoke detector by way of example.
First, a first embodiment is described with reference to FIGS. 1 to 7.

A smoke detector 1 exemplified as an electric device has a box-like
appearance with a casing 2. An opening portion 4 is formed in a front wall 3 of
peripheral walls of the casing 2. The casing 2 is provided with a cover 5
including a lid portion 5a for opening and closing the opening portion 4.
Note that, the smoke detector 1 optically detects the smoke and the like
floating in the air. Although detailed description thereof is omitted, the smoke
detector 1 includes, in the casing 2, a smoke detecting unit for optically
detecting the smoke, and a fan and an air duct for causing the sampled air to
flow into a smoke detecting portion provided in the smoke detecting unit.
In this example, the opening portion 4 is provided with, for example, a
terminal 6 used for external communication and a jack 7 used for telephone.
The terminal 6 and the jack 7 are covered with the lid portion 5a of the cover 5
when the lid portion 5 a of the cover 5 closes the opening portion 4 as illustrated
in FIG. 1, and are exposed to the outside when the lid portion 5a of the cover 5
opens the opening portion 4 as illustrated in FIG. 2.
Below the opening portion 4, there is provided a slit-like hole 8 through
which the cover 5 is allowed to be inserted/removed and movably inserted
into/removed from the casing 2. Further, around the opening portion 4, there is
provided a cover locking portion 9 to which the cover 5 is locked in the
substantially upright posture while covering the opening portion 4 with the lid
portion 5 a thereof. The cover locking portion 9 includes a recess formed to
allow an outer surface of the cover 5 to be flush with an outer surface of the
front wall 3 when the cover 5 is locked in the substantially upright posture.
Further, the cover locking portion 9 includes a magnet 10 provided above the

opening portion 4, for attracting the cover 5 due to its magnetic force and
keeping the cover 5 locked in the substantially upright posture.
The cover 5 includes a first bent portion 5b, an intermediate portion 5i,
and a second bent portion 5c which are provided in series to be continuous with
the flat-plate-like lid portion 5a. The first bent portion 5b and the second bent
portion 5c are respectively formed into substantially L-shapes, and are
continuously formed into a step shape. Further, in the cover 5, substantially
L-shaped outer and inner surfaces of each of the first bent portion 5b and the
second bent portion 5c are formed into curved surfaces by bending. Note that,
the cover 5 is made of metal, and is directly attracted to the magnet 10 provided
to the cover locking portion 9 due to the magnetic force. The cover 5 may be
formed of a resin molded product, and may be retained by, instead of the magnet
10, locking means respectively provided to the cover 5 and a bottom surface 9a
of the recess of the cover locking portion 9.
As illustrated in FIGS. 3A to 3C, in a state in which the lid portion 5a
closes the opening portion 4, the cover 5 is inserted through the hole 8, and takes
the substantially upright posture while the lid portion 5a is exposed to the
outside from the hole 8. In this case, the substantially L-shaped inner surface
of the second bent portion 5c of the cover 5 is engaged with a substantially
L-shaped surface formed of a lower inner wall surface 8b of the hole 8 and an
inner wall surface 3 a of the front wall 3 which is perpendicular and continuous
to the lower inner wall surface 8b. With this structure, the cover 5 takes the
substantially upright posture. Note that, flange portions 5f protruding to both
sides of the cover 5 are provided to a flat-plate portion continuous with the

second bent portion 5c on a proximal end 5h side of the cover 5. The flange
portions 5f can prevent the cover 5 from slipping off from the hole 8 to the
outside.
In addition, specifically, as illustrated in FIGS. 7A to 7C, the cover can
pivot at a corner portion 5d on an inner side of the substantially L-shaped first
bent portion in an arrow Al direction and an arrow A2 direction, i.e., in a
fore-and-aft direction with an inner edge portion 8c at an intersection between
an upper inner wall surface 8a of the hole 8 and the inner wall surface 3a of the
front wall as a fulcrum. Thus, it is possible to displace the cover 5 between the
substantially upright posture of closing the opening portion 4 and the
substantially laid posture of opening the opening portion 4, and it is possible to
open and close the opening portion 4. Further, a corner portion 5e on an inner
side of the substantially L-shaped second bent portion is engaged with an inner
edge portion 8d located at an intersection between the lower inner wall surface
8b of the hole 8 and the inner wall surface 3 a of the front wall, and hence it is
possible to prevent the cover 5 from rattling in an up-down direction in a
recessed surface of the cover locking portion 9.
A cover receiving portion 11 is provided in the casing 2 on the inner side
of the hole 8. The cover 5 is moved into the casing 2 through the hole 8 while
taking the substantially laid posture, and is received in the cover receiving
portion 11 while taking the substantially laid posture. Note that, the flange
portions 5f of the cover 5 are hooked to a pair of hooks 12, and the cover 5 is
kept to be received in the cover receiving portion 11. Note that, the cover 5 is
received in the cover receiving portion 11 in a state in which a forward end 5g of

the lid portion 5 a is exposed from the hole 8 to the outside. When the cover 5
closes the opening portion 4, the cover 5 can be easily removed from the casing
2 through pinching the forward end of the cover 5.
As described above, in the smoke detector 1, the cover 5 can be
inserted/removed through the hole 8, that is, can be attached to/detached from
the casing 2, and the cover pivots in the fore-and-aft direction at the corner
portion 5d on the inner side of the first bent portion with the inner edge portion
8c at the intersection between the upper inner wall surface 8a of the hole 8 and
the inner wall surface 3 a of the front wall as a fulcrum. Further, the cover 5 is
displaced between the substantially upright posture and the substantially laid
posture, and hence the opening portion 4 can be opened and closed. Further, in
the substantially laid posture, that is, in a state of opening the opening portion 4,
the cover 5 can be received in the cover receiving portion 11 of the casing 2.
Here, procedures for attaching the cover 5 to the casing 2 are described.
First, the lid portion 5 a of the cover 5 in the laid posture is inserted through the
hole 8 from the inner side thereof. Next, when the corner portion 5d on the
inner side of the first bent portion 5b comes into contact with the inner edge
portion 8c, after the cover 5 starts to rotate with the corner portion 5d as a
fulcrum, the first bent portion 5b can be passed through the hole 8. In
accordance with this, the cover 5 starts to be displaced to the substantially
upright posture. Moreover, when the cover 5 takes the substantially upright
posture, the intermediate portion 5i can be passed through the hole 8, and hence
the cover 5 makes substantially parallel movement in this posture. Finally,
when the corner portion 5e on the inner side of the second bent portion 5c comes

into contact with the inner edge portion 8d of the hole 8 serving as the engaging
means, the cover 5 is kept in the substantially upright posture. Note that, in
order to detach the cover 5 from the casing 2, operations reverse to the
above-mentioned operations may be performed. Each of the corner portions
does not mean merely one point, but includes a substantially L-shaped surface
around the corner portion. Further, according to the shapes of the inner corner
portions 5d and 5e, parts of the corner portions with which the fulcrum (inner
edge portion 8c) and the engaging means (inner edge portion 8d) come into
contact are changed.
Next, a second embodiment of the present invention is described with
reference to FIGS. 8 to 10.
As illustrated in FIGS. 8 to 10, in the second embodiment, the cover
receiving portion 11 further includes a stopper 13 and a guide claw 14. Other
configuration is substantially the same as that of the first embodiment.
The stopper 13 is a plate-like member provided upright at a position on a
front side of the guide claw 14 so as to be perpendicular to a bottom 11a (bottom
plate of the casing 2) of the cover receiving portion 11. The proximal end 5h
of the cover 5 inserted through the hole 8 is brought into contact with the
stopper 13, and thus movement of the cover 5 into the casing 2 is restricted.
The guide claw 14 is provided obliquely at a position on a back side of
the stopper 13 so as to be inclined forward with respect to the bottom 11a
(bottom plate of the casing 2) of the cover receiving portion 11. A forward end
14a including two columnar members as free ends is located above the stopper
13 and the hole 8. The guide claw 14 has elasticity, and the forward end 14a

has an angle sloping upward in oblique and perpendicular directions. The
flat-plate portion of the cover 5 is hooked to the forward end 14a from above.
However, when the cover 5 is released from the hooked state, the guide claw 14
can bias the outward movement of the cover 5.
As described above, the second embodiment is the same as the first
embodiment other than the configuration having the stopper 13 and the guide
claw 14. Also in the smoke detector 1 in the second embodiment, the cover 5
can be inserted/removed through the hole 8, that is, can be attached to/detached
from the casing 2, and the cover pivots in the fore-and-aft direction at the corner
portion 5d on the inner side of the first bent portion with the inner edge portion
8c at the intersection between the upper inner wall surface 8a of the hole 8 and
the inner wall surface 3a of the front wall as a fulcrum. Further, the cover 5 is
displaced between the substantially upright posture and the substantially laid
posture, and hence the opening portion 4 can be opened and closed. Further, in
the substantially laid posture, that is, in a state of opening the opening portion 4,
the cover 5 can be received in the cover receiving portion 11 of the casing 2.

We Claim:
1. An electric device, comprising:
a casing comprising an opening portion formed in a peripheral wall
thereof; and
a cover comprising a lid portion for opening and closing the opening
portion, wherein:
the cover further comprises a first bent portion and a second bent
portion which are provided in series to be continuous with the lid portion;
the casing comprises:
a hole allowing the cover to be inserted/removed
into/from the casing therethrough and to be movable in its insertion/removal
direction, the hole being provided in a vicinity of the opening portion; and
a cover locking portion to which the cover is locked in a
substantially upright posture while covering the opening portion with the lid
portion thereof, the cover locking portion being provided around the opening
portion; and
the cover is pivotable in a fore-and-aft direction at a corner
portion on an inner side of the first bent portion of the cover with an inner edge
portion at an intersection between an upper inner wall surface of the hole and an
inner wall surface of a front wall as a fulcrum, and the cover is allowed to be
displaced between the substantially upright posture and a substantially laid
posture.

2. An electric device according to claim 1, wherein the first bent portion
and the second bent portion are respectively formed into substantially L-shapes,
and the first bent portion and the second bent portion are continuously formed
into a step shape.
3. An electric device according to claim 1 or 2, wherein a corner portion
on an inner side of the second bent portion is engaged with an inner edge portion
located at an intersection between a lower inner wall surface of the hole and the
inner wall surface of the front wall.
4. An electric device according to any one of claims 1 to 3, wherein the
cover locking portion comprises a recess formed to allow an outer surface of the
cover to be flush with an outer surface of the peripheral wall of the casing when
the cover takes the substantially upright posture.
5. An electric device according to any one of claims 1 to 4, wherein the
cover is made of metal, and the cover locking portion comprises a magnet to
which the cover is attracted so that the cover is kept in the substantially upright
posture.
6. An electric device according to any one of claims 1 to 5, wherein the
casing comprises a cover receiving portion in which the cover is received in the
substantially laid posture, the cover receiving portion being provided on an inner
side of the hole.

7. An electric device according to any one of claims 1 to 6, wherein the
cover receiving portion comprises a biasing member for biasing movement of
the cover to an outside of the casing.

A cover (5) includes a first bent portion (5b) and a second bent portion
(5c) which are provided in series to be continuous with a lid portion (5a). A
casing (2) includes a hole (8) through which the cover is allowed to be
inserted/removed and movably inserted into/removed from the casing, and
includes a cover locking portion (9) to which the cover is locked in a
substantially upright posture while covering an opening portion (4) with the lid
portion. The cover can pivot in a fore-and-aft direction at a corner portion (5d)
on an inner side of the first bent portion with an inner edge portion (8c) at an
intersection between an upper inner wall surface (8a) of the hole and an inner
wall surface (3a) of a front wall as a fulcrum. The cover can be displaced
between the substantially upright posture and a substantially laid posture.