Planetary gear transmission systems or components – Electric or magnetic drive or control
Reexamination Certificate
1999-03-02
2001-05-22
Estremsky, Sherry (Department: 2851)
Planetary gear transmission systems or components
Electric or magnetic drive or control
C475S169000, C475S269000
Reexamination Certificate
active
06234931
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a driving force transmission apparatus used for an image reading apparatus such as an image scanner, a digital copying machine and the like for reading image information on a manuscript.
2. Description of the Related Art
In recent years, due to a high speed and a high resolution in reading an image by an image reading apparatus, in order to achieve both a high speed driving for reading the image at a high speed and a low speed driving for reading the image at a high resolution, a driving force transmission apparatus is required reading at a higher speed ratio. Further, the image reading apparatus has been made compact and inexpensive year by year, so that the driving force transmission apparatus therefor is required to be made compact and inexpensive as well as to be provided with a high speed ratio.
A conventional driving force transmission apparatus will be described below.
FIG. 4
is a cross sectional view of an image reading apparatus using a conventional driving force transmission apparatus,
FIG. 5
is a perspective view of the image reading apparatus using the conventional driving force transmission apparatus, and
FIG. 6
is a perspective view of main construction members in the conventional driving force transmission apparatus.
In
FIG. 4
, reference numeral
1
denotes a frame body of a main body of an image scanner corresponding to an image reading apparatus, reference numeral
2
denotes a manuscript, reference numeral
3
denotes a manuscript table glass on which the manuscript is placed, reference numeral
4
denotes a manuscript pressing plate for adhering the manuscript
2
to the manuscript table glass
3
, reference numeral
5
denotes a fluorescent lamp for lighting the manuscript
2
, reference numeral
6
denotes a reflecting mirror, reference numeral
7
denotes a image forming lens for forming a light image, reference numeral
8
denotes a CCD in which some thousands of photo-electric conversion components for converting the light image formed by the image forming lens
7
into an electric signal in accordance with a photo-electric conversion are arranged on a line, and reference numeral
9
denotes an optical carriage corresponding to a moving body obtained by integrally constituting the reflecting mirror
6
, the image forming lens
7
and the CCD
8
.
In
FIG. 5
, reference numeral
10
denotes a rail for supporting the optical carriage
9
in such a manner as to move linearly, reference numeral
11
denotes a driving unit, reference numeral
12
denotes a driving pulley, reference numeral
13
denotes a transmission belt rotated by the driving pulley
12
, and reference numeral
14
denotes a driven pulley tensioning the transmission belt
13
together with the drive pulley
12
.
In
FIG. 6
, reference numeral
15
denotes a driving motor for generating a rotational force, reference numerals
16
and
17
denote a pulley, reference numeral
18
denotes a transmission belt tensioned between the pulleys
16
and
17
, reference numeral
19
denotes a clutch, and reference numeral
20
denotes a shaft connected to the driving pulley
12
. A rotation of the pulley
17
can be transmitted to the shaft
20
when the clutch
19
is energized. Reference numerals
21
,
22
,
23
and
24
denote a pulley, in which the pulley
21
is connected to the pulley
17
and the pulley
24
is connected to the shaft
20
, respectively. Reference numerals
25
and
27
denote a transmission belt tensioned between the pulleys
21
and
22
and the pulleys
23
and
24
, respectively, reference numeral
28
denotes a clutch, and reference numeral
29
denotes a shaft connected to the pulley
23
. A rotation of the pulley
22
can be transmitted to the shaft
29
when the clutch
28
is energized.
With respect to the conventional driving force transmission apparatus structured in the manner mentioned above, an operation thereof will be described below with reference to
FIGS. 4
to
6
.
In
FIGS. 4 and 5
, a reflecting light after lighting the manuscript
2
by the fluorescent lamp
5
is reflected by the reflecting mirror
6
so as to form an image on the CCD
8
by the image forming lens
7
, so that the image corresponds to a line of the manuscript
2
by the CCD
8
. The driving unit
11
rotates the transmission belt
13
, and the optical carriage
9
moves in a direction of an arrow A together with the transmission belt
13
, whereby all the surface of the manuscript
2
can be read.
In this case, in order to read the manuscript
2
, it is necessary to rotate the driving unit
11
at a high speed so as to move the optical carriage
9
at a high speed. Further, since a time for which the CCD
8
reads a line of the manuscript
2
is constant, in order to read the manuscript
2
at a high resolution, it is necessary to rotate the driving unit
11
at a low speed so as to move the optical carriage
9
at a low speed. By doing so, it is possible to read the manuscript
2
at a high density in a moving direction of the optical carriage
9
.
Next, in
FIG. 6
, in the case that the clutch
19
is energized, the rotation of the driving motor
15
is transmitted to the pulley
16
, the transmission belt
18
, the pulley
17
, the shaft
20
and the driving pulley
12
, and the rotation of the driving motor
15
is reduced in accordance with a one-step speed reduction by the pulleys
16
and
17
. Further, in the case that the clutch
28
is energized, the rotation of the driving motor
15
is transmitted to the pulley
16
, the transmission belt
18
, the pulley
17
, the pulley
21
, the transmission belt
25
, the pulley
22
, the shaft
29
, the pulley
23
, the transmission belt
26
, the pulley
24
, the shaft
20
and the driving pulley
12
, and the rotation of the driving motor
15
is further reduced in accordance with a three-step speed reduction by the pulleys
16
and
17
, the pulleys
21
and
22
, and the pulleys
23
and
24
.
As mentioned above, a speed ratio higher than a speed ratio of the driving motor
15
itself can be obtained by transmitting the rotation from the driving motor
15
in accordance with two systems of rotational force transmission paths.
However, in order to achieve a high speed ratio, in accordance with the conventional structure mentioned above, there is a problem that the driving unit
11
requires a large size and an expensive cost since a plurality of pulleys, transmission belts and clutches are required, and further, the image forming apparatus is made with an increased size and expense.
SUMMARY OF THE INVENTION
The present invention is directed to solving the problem in the conventional apparatus mentioned above, and an object of the present invention is to provide a driving force transmission apparatus which can achieve both a high speed structure and a compact and inexpensive structure.
In order to achieve the object mentioned above, in accordance with the present invention, there is provided a driving force transmission apparatus which can achieve both a compact size and an inexpensive cost by arranging speed change means and connecting means for selectively transmitting any one of a rotational force from the speed change means and a rotational force not passing through the speed change means in series.
REFERENCES:
patent: 2480210 (1949-08-01), Avila
patent: 2533056 (1950-12-01), Selby
patent: 3430521 (1969-03-01), Kulman
patent: 4270411 (1981-06-01), Pengo et al.
patent: 4286480 (1981-09-01), Dickie
patent: 4440042 (1984-04-01), Holdeman
patent: 4878399 (1989-11-01), Kameda
patent: 5045036 (1991-09-01), Reuter et al.
patent: 5123883 (1992-06-01), Fukaya
Estremsky Sherry
Matsushita Electric - Industrial Co., Ltd.
Stevens Davis Miller & Mosher LLP
LandOfFree
Driving force transmission apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Driving force transmission apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Driving force transmission apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2440517