Electricity: electrical systems and devices – Housing or mounting assemblies with diverse electrical... – For electronic systems and devices
Reexamination Certificate
1999-03-30
2001-08-07
Tolin, Gerald (Department: 2835)
Electricity: electrical systems and devices
Housing or mounting assemblies with diverse electrical...
For electronic systems and devices
C248S048200, C312S236000, C361S727000, C361S802000
Reexamination Certificate
active
06272013
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a unit housing structure in an electronic device provided with a guide structure for smoothly guiding a detachable unit portion to a predetermined position in a unit mounting portion.
2. Description of the Related Art
In an electronic device composed of a plurality of printed boards packaged on a shelf, for example, in a communication apparatus, heat generation from the printed boards is a problem. Structure for emitting the heat outside is therefore employed. Commonly employed as this cooling method is forced air cooling using a fan. The fan has a certain life expectancy, but may encounter trouble prior to the expiration of its known life expectancy. For facilitating maintenance and replacement, therefore, it is a common practice for a fan unit to be structured to be detachable from the front side of a unit mounting portion in the body of a device.
Furthermore, since the fan unit needs to supply power or transmit an alarm signal or the like when the number of revolutions of the fan is reduced, the unit requires electrical connection with the device side. The fan unit and the unit mounting portion of the device are therefore both designed to have a connector through which the fan unit and the unit mounting portion are electrically connected.
In addition, for reliably connecting the connectors, the fan unit should be guided such that the connectors face each other while positioned with respect to each other. For this guiding, a guide rail with a groove for guiding is disposed on the side of the unit mounting portion.
Commonly used as this guide rail is a rail having a U-shaped slot whose opposite sides rise vertically to the bottom surface (hereinafter, referred to as a U slot). The fan unit is guided by engaging a guided portion on the fan unit side with this U slot and sliding the guided portion within the U slot. Here, between the U slot of the guide rail and the guided portion of the fan unit, “the width of the U slot is greater than the width of the guided portion” holds and the two are designed to have a little clearance therebetween.
It is ideal that insertion or extraction of the fan unit into or from the unit mounting portion is conducted while keeping the U slot of the guide rail and the guided portion of the fan unit in parallel to each other at any time.
Among modes of a fan unit are a mode of laterally mounting a plurality of fan units each having a few fans so as to meet cooling design or a design concept of an electronic device and a mode of mounting a fan unit large in breadth having numbers of fans thereon. In either mode, for guiding a fan unit large in breadth by a U slot of a guide rail, operating the U slot of the guide rail and a guided portion of the unit while constantly keeping them in parallel with each other is difficult and the unit is highly likely to slant with its left side or right side projecting forward. As a result, an apparent width of the guided portion of the fan unit equals or exceeds the width of the U slot of the guide rail, whereby the guided portion of the fan unit will be pressed against the inner wall surface of the U slot to hitch halfway in the insertion or extraction.
In a case where a right and left slant is to be corrected for rectifying this state, when the amount of rectification is too large, a right and left slant reverse to that before will cause a hitch. Insertion and extraction are highly likely to be conducted through the repetition of this movement to rock the unit leftward and rightward alternately in the traveling direction and cause a hitch. This tendency is more enhanced as the breadth of the fan unit is increased.
Under these circumstances, there is a demand for a unit housing structure provided with a guide structure which enables smooth insertion and extraction without a hitch caused by rocking from side to side.
FIGS. 11 and 12
show one example of a conventional housing structure and
FIG. 11
is a perspective view showing a broken-out section of a part of the schematic structure of the housing structure and
FIG. 12
is an expanded sectional view taken along line B—B of FIG.
11
. More specifically, shown are one example of a fan unit
110
large in breadth having a plurality of fans
175
provided thereon and a fan unit mounting portion
120
in which the fan unit
110
is to be mounted. Although not shown, the fan unit mounting portion
120
is disposed within an electronic device such as a communication apparatus.
In more detail, the fan unit mounting portion
120
has a connector
130
for the connection with the fan unit
110
. The connector
130
is connected to the inside of the electronic device by a cable to allow power supply to the fan unit
110
or detect an alarm signal or the like generated from the fan unit
110
due to the reduction of the number of revolutions of the fan. On the left side on cross-beams
180
and
190
of the fan unit mounting portion
120
, a guide rail
140
for guiding the fan unit
110
is provided. The guide rail
140
, as illustrated in
FIG. 12
, forms a U slot
170
having its wall surfaces rising perpendicularly to the bottom surface by which the U slot
170
guides the fan unit
110
.
On the other hand, the fan unit
110
has a connector
150
at a position opposed to the connector
130
of the fan unit mounting portion
120
. In addition, the lower edge of the side surface of the fan unit
110
projects to become a guided portion
160
which will be guided while being fit in the U slot
170
of the guide rail
140
. Here, the width of the U slot
170
of the guide rail
140
has a dimension with a little clearance with respect to the board thickness of the side surface of the fan unit
110
, that is, the width of the guided portion
160
.
Next, operation at the conventional housing structure will be described. First, set the guided portion
160
of the fan unit
110
to the U slot
170
of the guide rail
140
to insert the fan unit
110
into the fan unit mounting portion
120
. Insertion is enabled without any problem by inserting the fan unit
110
straight on, with the U slot
170
of the guide rail
140
and the guided portion
160
of the fan unit
110
maintained in parallel to each other at any time by keeping a balance between right and left.
Once the balance between right and left is lost and the fan unit
110
slants, for example, as illustrated in
FIG. 13
, the guided portion
160
slants to the utmost within the U slot
170
of the guide rail
140
, resulting in having the apparent width of the guided portion
160
equaling or exceeding the width of the U slot
170
of the guide rail
140
. As a result, the guided portion
160
of the fan unit
110
is pressed against the inner wall surface of the U slot
170
to cause a hitch halfway in the insertion of the fan unit
110
.
Here, at the time of correcting the right and left slant by pushing the left side, as one faces it, of the fan unit
110
in order to rectify the slant state, if the amount of rectification is too large, a right and left slant reverse to that of
FIG. 13
is generated, for example, as illustrated in
FIG. 14
to cause a hitch. Repetition of this movement will result in insertion with the unit rocking rightward and leftward in the traveling direction.
As described in the foregoing, a conventional structure for guiding a unit large in breadth by means of a guide rail having a U slot involves rightward and leftward rocking in the traveling direction to cause a hitch, making mounting of the fan unit difficult. This tendency is more enhanced when the guide rail
140
of the fan unit mounting portion
12
and the guided portion
160
of the fan unit
110
are both made of metal for maintaining the ground potentials of the fan unit mounting portion
120
and the fan unit
110
to be the same than that when either the guide rail
140
or the guided portion
160
is made of a resin material.
Although the foregoing description has been made of the structure for housing the fan unit
110
in the fan unit mo
McGuireWoods LLP
NEC Corporation
Tolin Gerald
LandOfFree
Unit housing structure in electronic device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Unit housing structure in electronic device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Unit housing structure in electronic device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2494823