Electricity: electrical systems and devices – Housing or mounting assemblies with diverse electrical... – For electronic systems and devices
Reexamination Certificate
2001-07-05
2004-06-22
Zarneke, David A. (Department: 2827)
Electricity: electrical systems and devices
Housing or mounting assemblies with diverse electrical...
For electronic systems and devices
C361S816000, C174S034000
Reexamination Certificate
active
06754088
ABSTRACT:
FIELD OF THE INVENTION
This invention relates to a shield for emitted radio waves and an image forming apparatus that uses such a shield. More particularly, the invention relates to art that makes the assembly and inspection of such apparatus more efficient.
BACKGROUND OF THE INVENTION
A shield against emitted radio waves in the conventional image forming apparatus includes a shield box the opening of which is formed to have a flange, and a shield plate secured to the flange using screws that are threadedly engaged with screw holes formed in the flange at prescribed intervals. A board for image processing is secured to the bottom side of the shield box by screws or the like. This arrangement prevents the escape of radio waves emitted from the board for image processing.
An alternative arrangement is shown in
FIG. 5
, which is an external perspective view of an emitted-radio-wave shield according to the prior art. This shield includes a shield box
201
the opening of which has flanges
201
b
formed on its four sides
201
a
, and a shield plate
203
secured to the flanges
201
b
using screws
210
that are threadedly engaged with screw holes
201
c
formed in the flanges
201
b
at prescribed intervals. A board
202
(indicated by the dashed lines) for image processing is secured to the bottom side of the shield box
201
by screws or the like (not shown). Further, the shield plate
203
is secured to the flanges
201
b
of the shield box via shield members
204
that have been cut to prescribed lengths, thereby reducing the number of screws
210
needed to secure the shield plate
203
to the shield box
201
.
With the emitted-radio-wave shield constructed as set forth above, a large number of the screws
210
are necessary to secure the shield plate
203
to the shield box
201
. When the board
202
for image processing is accessed, all of the screws
210
must be removed. Such an arrangement has a poor workability.
Further, when shield members
204
are provided, as shown in
FIG. 5
, it is difficult to provide sufficient flatness for the shield plate
203
. As a result, in order to reliably prevent the escape of radio waves from the board
202
, securing by way of the screws
210
is required. Though it is possible to reduce the number of screws over the former arrangement, there is still not much improvement in workability.
SUMMARY OF THE INVENTION
Accordingly, an object of the present invention is to provide an emitted-radio-wave shield and an image forming apparatus that uses such a shield, the shield being composed of a shield box, which houses a circuit board, and a shield plate, wherein the operation for attaching and removing the shield plate in order to access the board is simplified and leakage of emitted radio waves can be prevented.
According to the present invention, an emitted-radio-wave shield comprises a shield box housing a circuit board; a shield plate removably secured to the shield box; and a shield member, which is disposed at a joint between the shield box and the shield plate and is electrically connected with the shield box, for shielding emitted radio waves from the circuit board in a state in which the shield plate is secured to the shield box; wherein the shield plate is formed to have a plurality of protrusions, which project toward the shield member, at a part thereof that contacts the shield member.
Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.
REFERENCES:
patent: 5170321 (1992-12-01), Oslund et al.
patent: 5383098 (1995-01-01), Ma et al.
patent: 5591050 (1997-01-01), Sueoka
patent: 5895884 (1999-04-01), Davidson
patent: 5919062 (1999-07-01), Wu
patent: 6051780 (2000-04-01), Furhmann et al.
patent: 6194653 (2001-02-01), McMiller et al.
patent: 6301125 (2001-10-01), Maeda
Canon Kabushiki Kaisha
Dinh Tuan
Fitzpatrick ,Cella, Harper & Scinto
Zarneke David A.
LandOfFree
Emitted-radio-wave shield and image forming apparatus using... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Emitted-radio-wave shield and image forming apparatus using..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Emitted-radio-wave shield and image forming apparatus using... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3345585