Arrangement and method for attaching image sensor to electronic machine

A method of attaching an image sensor having a frame at the mounting position of an electronic machine. Protruding portions are formed on both side surfaces of the frame, and a fitting guide is provided at the mounting position of the electronic machine. One end of the fitting guide is a rectilinearly bent engaging portion and the other end is an arc-shaped engaging portion. When the image sensor is pushed to the mounting portion, the protruding portions engage the respective engaging portions, whereby the image sensor is fixed.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an image sensor incorporated into an 
electronic machine such as a facsimile machine, a copying machine or an 
optical character reader. 
2. Description of the Related Art 
A conventional image sensor is generally composed of a transparent cover 
attached to the upper portion of a frame so as to bring the surface of the 
cover into contact with the object of imaging, the frame encasing a 
light-emitting portion for projecting light onto the object, an optical 
system for converging the light reflected from the object and a 
light-receiving portion for receiving the light from the optical system. 
The light-emitting portion and the light-receiving portions are provided 
on the respective substrates, and these substrates are fixed to the frame. 
Methods of attaching such an image sensor to an electronic machine such as 
a facsimile machine or a copying machine are roughly classified into the 
two methods shown in FIGS. 5 and 6. In the method shown in FIG. 5, 
threaded holes 41a, 41b are formed in both longitudinal side surfaces of a 
frame 41 of an image sensor 40 having a transparent cover (glass cover) 
42, and two L-shaped plate members 50, 51 are provided at the mounting 
portion of the electronic machine to which the image sensor 40 is 
attached. Holes 50a, 51a, and 50b, 51b which correspond to the threaded 
holes 41aand 41b, respectively, are formed in the plate members 50 and 51, 
respectively. Screws 52, 54 and 53, 55 are passed through the holes 50a, 
50b, and 51a, 51b so as to be engaged with the threaded Roles 41a and 41b, 
respectively. Both end surfaces of the image sensor 40 are thus sandwiched 
between the plate members 50 and 51, and in this state the image sensor 40 
is fixed to the electronic machine. 
In the method shown in FIG. 6, two threaded holes 61a, 61b are formed in 
both side surfaces of a frame 61 of an image sensor having a glass cover 
62, and two L-shaped plate members 70, 71 are provided at the mounting 
portion of the electronic machine to which the image sensor 60 is 
attached. Holes 70a, 71a, and 70b, 71b which correspond to the threaded 
holes 61a and 61b, respectively, are formed in the plate members 70 and 
71, respectively. Screws 72, 74, 73 and 75 (not shown) are passed through 
the holes 70a, 71a, and 70b, 71b so as to be engaged with the threaded 
holes 61a and 61b, respectively. Both side surfaces of the image sensor 60 
are thus sandwiched between the plate members 70 and 71, and in this state 
the image sensor 60 is fixed to the electronic machine. 
In both of the methods shown in FIG. 5 and 6, it is necessary to form the 
threaded holes in the frame of the image sensor. This machining cost is 
very high. In addition, since it is necessary to pass the screws first 
into the plate members and thereafter engage them with the threaded holes 
of the frame when the image sensor is attached to the electronic machine, 
attachment of the image sensor to the electronic machine is time and labor 
intensive. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to eliminate the 
above-described problems in the related art and to provide an arrangement 
and a method for attaching an image sensor to an electronic machine with 
ease and at a low cost. 
To achieve this aim, in the present invention, an image sensor is provided 
with a frame having an interlocking portion which fits into the mounting 
portion of an electronic machine to which the image sensor is attached. 
According to this structure, the interlocking portion of the frame is 
fitted into the mounting portion of the electronic machine simply by 
pushing the image sensor into the mounting portion of the electronic 
machine, so that the image sensor is easily fixed to the electronic 
machine. Since the frame is generally produced by extrusion molding, even 
if the frame has a slightly complicated shape, the cost is not raised and 
is rather reduced by the equivalent of the cost of threading which is 
required in a conventional frame.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
An image sensor in accordance with the present invention will now be 
explained with reference to the embodiments. 
FIG. 1 shows an image sensor 10 in accordance with the present invention 
which is attached to the mounting portion 20 of an electronic machine such 
as a facsimile machine or a copying machine. The image sensor 10 is 
approximately the same as a conventional image sensor except for the 
external shape of a frame 11. A transparent cover (glass cover) 12 is 
attached to the upper portion of the frame 11, and a side plate 13 is 
provided on both end surfaces of the image sensor 10. The frame 11 encases 
a substrate provided with a light-emitting device (e.g., LED chip), a 
substrate provided with a light-receiving element (e.g., photodiode chip), 
a rod lens array as an optical system for converging the light reflected 
from the copy W on the transparent cover 12, etc. 
The light emitted from the light-emitting device illuminates the original W 
which is fed onto the glass cover 12 by a platen roller 22. The light 
reflected from the original W is converged by the rod lens array, and is 
received and converted into an electric signal by the light-receiving 
device. 
On both longitudinal side surfaces of the frame 11, protruding portions 11a 
and lib are formed in the longitudinal direction. Since the frame 11 is 
produced by extrusion molding, as described above, it is possible to 
produce the frame 11 having the protruding portions 11a, 11b easily and at 
a low cost. 
The electronic machine is provided at the mounting portion 20 with a 
fitting guide 21 having the shape shown in FIG. 1. The fitting guide 21 
has, at one end, an engaging portion 21a which is bent in a perpendicular 
fashion and, at the other end, an engaging portion 21b which is bent into 
an arc and an extending portion 21c which linearly extends from the 
engaging portion 21b. The fitting guide 21 may be produced either by sheet 
metal working or by extrusion of a resin, a metal, etc. 
The protruding portions 11aand 11b of the frame 11 are engaged with the 
engaging portions 21a and 21b, respectively, of the fitting guide 21. It 
is therefore possible to incorporate the image sensor 10 into the 
electronic machine simply by pushing the image sensor 10 into the mounting 
portion 20. Since the protrusion 11a is engaged with the engaging portion 
21a and the protruding portion 11b is engaged with the engaging portion 
21b, the image sensor 10 is securely fixed to the mounting portion 20 due 
to the appropriate elasticity of the fitting guide 21. 
In attaching the image sensor 10 to the electronic machine, instead of 
pushing the image sensor in a direction perpendicular to the mounting 
portion 20 from above, as described above, the protruding portion 11a may 
be first engaged with the engaging portion 21a by inclining the image 
sensor with the protruding portion 11a faced downward, and thereafter the 
image sensor 10 may be rotated clockwise in FIG. 3 so as to engage the 
protruding portion 11b with the engaging portion 21b. 
Each of the protruding portions 11a and 11b has a tapered surface, and 
since the engaging portion 21a is inclined downward and the engaging 
portion 21b is arched, the protruding portions 11a, 11b are not caught by 
the engaging portions 21a and 21b, respectively. It is therefore easy to 
push the image sensor 10 into the mounting portion 20. In order to remove 
the image sensor 10, the engagement between the protruding portion 11b and 
the engaging portion 21b is released by pushing the extending portion 21c 
by a screw driver or the like. In this way, quick removal of the image 
sensor 10 is possible, for example, at the time of reworking the image 
sensor. 
Although the image sensor 30 is slightly unstable due to a tolerance when 
the image sensor 30 is fitted into the mounting portion 20 by the 
engagement between the protruding portions 11a, 11b and the engaging 
portions 21a, 21b, since the image sensor 10 is pressed against the 
mounting portion 20 by the platen roller 22 during use, it produces no 
problem. 
FIG. 2 shows a second embodiment. This embodiment has approximately the 
same structure as the first embodiment shown in FIG. 1 except that tile 
image sensor and the fitting guide are disposed in the opposite direction 
to the image sensor 10 and the fitting guide 21 with respect to the 
direction of feeding the original W. In other words, an image sensor 30 
and a fitting guide 34 of this embodiment have the same structure as those 
in the first embodiment but the direction in which they are disposed is 
opposite. 
A transparent cover (glass cover) 32 is attached to the upper portion of a 
frame 31, and a side plate 33 is provided on both end surfaces of the 
image sensor 30. On both longitudinal side surfaces of the frame 31, 
protruding portions 31a and 31b are formed in the longitudinal direction. 
Since the frame 31 is produced by extrusion molding, as in the first 
embodiment, it is possible to produce the frame 31 having the protruding 
portions 31a, 31b with easiness and at low cost. 
The electronic machine is provided at the mounting portion 20 with the 
fitting guide 34 having the shape shown in FIG. 2. The fitting guide 34 
has, at one end, an engaging portion 34a which is bent in a perpendicular 
fashion and, at the other end, an engaging portion 34b which is bent into 
an arc and an extending portion 34c which linearly extends from the 
engaging portion 34b. 
The protruding portions 31a and 31b of the frame 31 are engaged with the 
engaging portions 34a and 34b, respectively, of the fitting guide 34. It 
is therefore possible to incorporate the image sensor 30 into the 
electronic machine simply by pushing the image sensor 30 into the mounting 
portion 20. Since the protrusion 31a is engaged with the engaging portion 
34a and the protruding portion 31b is engaged with the engaging portion 
34b, the image sensor 30 is securely fixed to the mounting portion 20 due 
to the appropriate elasticity of the fitting guide 34. 
Since each of the protruding portions 31a and 31b has a tapered surface, as 
in the first embodiment, it is easy to push and fix the image sensor 30 to 
the mounting portion 20. 
In this embodiment, the moment produced when the original W is fed, namely, 
the moment in the counterclockwise direction applied to the frame 31 is 
suppressed by the protruding portion 34a, thereby securing the image 
sensor 30 to the mounting portion 20 of the electronic machine. If the 
protruding portion 34a is so designed as to urge the frame 31 downward, 
the securing effect is further enhanced. 
FIG. 3 shows a third embodiment. In this embodiment, the frame has a 
slightly different shape from those of the first and the second 
embodiments. The frame of this embodiment is provided with a lower 
protruding portion 81b which corresponds to the protruding portions 11b, 
31b in the first and the second embodiments, and is further provided with 
an upper protruding portion 81c. A fitting guide 84 has approximately the 
same shape as the fitting guide 34 of the second embodiment, and an 
engaging portion 84a is engaged with a protruding portion 81a. An engaging 
portion 84b is engaged with the upper and the lower protruding portions 
81b and 84c, thereby fixing the frame 81. An extending portion 84c 
corresponding to the extending portion 34c in the second embodiment is 
formed on the fitting guide 84. 
Although the lower protruding portion 81b has no tapered surface, it is 
possible to attach the frame 81 to the mounting portion of the electronic 
machine by engaging first the protruding portion 81a with the engaging 
portion 84a, and thereafter engaging the protruding portions 81b and 81c 
with the engaging portion 84b while rotating the frame 81. 
FIG. 4 shows the arrangement of the fitting guide on the mounting portion 
of the electronic machine. In FIG. 4, the reference numerals correspond to 
the elements in the first embodiment shown in FIG. 1, but this arrangement 
is applicable to the guides in the other embodiments. The fitting guide 21 
is disposed on the back surface of the mounting portion 20 of the 
electronic machine such that the engaging portions 21a and 21b protrude 
from the upper surface of the mounting portion 20. Through holes 20a, 20b, 
20c and 20d having the sizes and the shapes corresponding to the 
respective engaging portions or positioning protrusions are formed in the 
mounting portion 20. The fitting guide 21 is fixed on the back surface of 
the mounting portion 20. Through the fitting guide 21 fixed in this 
manner, the image sensor 10 is attached to the electronic machine in the 
above-described manner. 
In none of the above-described embodiments, is it necessary to fix the 
frame by screws. As a result, it is possible to use not only a metal 
material such as aluminum but also a resin material such as polycarbonate 
as a frame material. That is, it is possible to constitute the image 
sensor even by a soft material which would not allow screwing. 
As described above, the image sensor in accordance with the present 
invention is provided with a frame having an interlocking portion which 
fits into the mounting portion of an electronic machine. This structure 
produces the following advantages: 
(1) Simply by pushing the image sensor into the mounting portion of the 
electronic machine, the interlocking portion of the frame fits into the 
mounting portion, thereby fixing the image sensor to the electronic 
machine. It is therefore possible to greatly reduce the time taken to 
attach the image sensor to the electronic machine. 
(2) Since the frame is generally produced by extrusion molding, the cost of 
the frame having the interlocking portion is not raised and is rather 
reduced by the equivalent of the cost of threading which is required in a 
conventional frame. 
While there has been described what are at present considered to be 
preferred embodiments of the invention, it will be understood that various 
modifications may be made thereto, and it is intended that the appended 
claims cover all such modifications as fall within the true spirit and 
scope of the invention.