U.S. patent application number 14/569146 was filed with the patent office on 2015-06-18 for conveyance roller and printing device.
The applicant listed for this patent is Funai Electric Co., Ltd.. Invention is credited to Yohei Emi, Shoichi Fukuyama, Masaaki Takagi.
Application Number | 20150166291 14/569146 |
Document ID | / |
Family ID | 52101069 |
Filed Date | 2015-06-18 |
United States Patent
Application |
20150166291 |
Kind Code |
A1 |
Fukuyama; Shoichi ; et
al. |
June 18, 2015 |
CONVEYANCE ROLLER AND PRINTING DEVICE
Abstract
A conveyance roller includes a shaft body including a
cylindrical roller base having a center axis coinciding with a
rotational axis of the shaft body, and an elastic member that
covers the roller base. The roller base includes either a
protrusion covered by the elastic member and provided on a lateral
surface of the roller base, or a through-hole that penetrates the
roller base in a direction parallel to a diameter of the roller
base and into which the elastic member is inserted.
Inventors: |
Fukuyama; Shoichi; (Osaka,
JP) ; Emi; Yohei; (Osaka, JP) ; Takagi;
Masaaki; (Kashihara-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Funai Electric Co., Ltd. |
Osaka |
|
JP |
|
|
Family ID: |
52101069 |
Appl. No.: |
14/569146 |
Filed: |
December 12, 2014 |
Current U.S.
Class: |
492/56 |
Current CPC
Class: |
B65H 3/0638 20130101;
G03G 15/6529 20130101; B65H 27/00 20130101; G03G 15/6552 20130101;
G03G 15/6511 20130101; G03G 2215/00679 20130101 |
International
Class: |
B65H 27/00 20060101
B65H027/00; B65H 3/06 20060101 B65H003/06 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 16, 2013 |
JP |
2013-258888 |
Claims
1. A conveyance roller, comprising: a shaft body comprising a
cylindrical roller base having a center axis coinciding with a
rotational axis of the shaft body; and an elastic member that
covers the roller base, wherein the roller base comprises either: a
protrusion covered by the elastic member and provided on a lateral
surface of the roller base, or a through-hole that penetrates the
roller base in a direction parallel to a diameter of the roller
base and into which the elastic member is inserted.
2. The conveyance roller according to claim 1, wherein the roller
base comprises a first protrusion and a second protrusion covered
by the elastic member and provided on a first lateral surface and a
second lateral surface of the roller base, respectively.
3. The conveyance roller according to claim 1, wherein the roller
base comprises a plurality of through-holes that penetrate the
roller base in a direction parallel to a diameter of the roller
base and into which the elastic member is inserted.
4. The conveyance roller according to claim 3, wherein a thickness
between adjacent through-holes among the plurality of
through-holes, a thickness between at least one of the plurality of
through-holes and the circumferential surface closest to the at
least one of the plurality of through-holes, and a thickness
between the at least one of the plurality of through-holes and the
lateral surface are substantially equal.
5. The conveyance roller according to claim 1, wherein a diameter
of the through-hole is less than or equal to a thickness of the
elastic member at the circumferential surface of the roller
base.
6. The conveyance roller according to claim 1, wherein the
through-hole is at least partially filled with the elastic
member.
7. The conveyance roller according to claim 1, wherein the elastic
member is outsert molded on the roller base.
8. The conveyance roller according to claim 1, wherein the shaft
body is made of a resin, and the elastic member is made of an
elastic resin.
9. A printing device, comprising: a conveyance roller comprising: a
shaft body comprising a cylindrical roller base having a center
axis coinciding with a rotational axis of the shaft body; and an
elastic member that covers the roller base, wherein the roller base
comprises either: a protrusion covered by the elastic member and
provided on one lateral surface of the roller base that is not a
circumferential surface of the roller base, or a through-hole that
penetrates the roller base in a direction parallel to a diameter of
the roller base and into which the elastic member is entered.
10. The printing device according to claim 9, wherein the roller
base further comprises another protrusion covered by the elastic
member and provided on another lateral surface of the roller
base.
11. The printing device according to claim 9, wherein the roller
base comprises a plurality of through-holes that penetrate the
roller base in a direction parallel to a diameter of the roller
base and into which the elastic member is inserted.
12. The printing device according to claim 11, wherein a thickness
between adjacent through-holes among the plurality of
through-holes, a thickness between at least one of the plurality of
through-holes and the circumferential surface closest to the at
least one of the plurality of through-holes, and a thickness
between the at least one of the plurality of through-holes and the
lateral surface are substantially equal.
13. The printing device according to claim 9, wherein a diameter of
the through-hole is less than or equal to a thickness of the
elastic member at the circumferential surface of the roller base of
the elastic member.
14. The printing device according to claim 9, wherein the
through-hole is at least partially filled with the elastic
member.
15. The printing device according to claim 9, wherein the elastic
member is outsert molded on the roller base.
16. The printing device according to claim 9, wherein the shaft
body is made of a resin, and the elastic member is made of an
elastic resin.
Description
TECHNICAL FIELD
[0001] The present invention relates generally to a conveyance
roller and a printing device comprising the conveyance roller. The
conveyance roller may be for example intended to convey a recording
medium.
BACKGROUND TECHNOLOGY
[0002] In conventional printing devices, for example, a conveyance
roller is configured by forming an elastic member enclosing a
roller base body. The roller base body has a cylindrical shape and
is mounted on a shaft body. Typically, the conveyance roller
includes a rotation stopper on the shaft body of the conveyance
roller.
[0003] For example, in the section "Background Technology" of
Patent Document 1, such a conveyance roller having a rotation
stopper is described.
[0004] FIG. 20, for example, shows a perspective view of a shaft
body of the conveyance roller described in the section of
"Background Technology" of Patent Document 1.
[0005] The shaft body 80 illustrated in FIG. 20 has a rotational
axis parallel to an x-axis and has a protrusion 82 that extends in
an x-axis direction on a circumferential surface of a roller base
body 81.
[0006] FIG. 21 shows a perspective view of an example of a
conveyance roller 8 formed with an elastic member 91 that covers
the roller base body 81. The elastic member 91 is formed by outsert
molding, for example, so as to cover the roller base body 81. The
roller base body 81 covered by the elastic member 91 functions as a
roller, after the elastic member 91 is solidified by cooling.
Moreover, the protrusion 82, by fitting with the elastic member 91,
functions as a rotation stopper on the shaft body 80, thus stopping
rotation of the elastic member 91.
[0007] However, as pointed out in Patent Document 1, the elastic
member 91, when cooled, contracts unevenly in a region of the
protrusion with respect to a region other than the protrusion of
the circumferential surface of the roller base body 81. This is due
to a difference in thickness of the elastic member 91. As a result,
a shape of the protrusion 82 is transferred slightly on a top
surface of the elastic member 91, thus generating a protuberance
92. Further, the circularity of a cross section parallel to a y-z
plane of the elastic member 91 (referred to hereinafter as a cross
section) is impaired, thereby reducing conveyance precision.
[0008] Patent Document 1 discloses a structure for a conveyance
roller used together with a driven roller to improve conveyance
precision.
[0009] FIG. 22 shows a perspective view of an example of the shaft
body of the conveyance roller disclosed in Patent Document 1.
[0010] On a shaft body 83 illustrated in FIG. 22, a groove 86 is
cut along a circumference of a roller base body 85 in a position
that does not oppose a driven roller 84. By forming the elastic
member on an outer peripheral surface of the roller base body 85,
one or more steps 87, resulting from not cutting the groove 86 all
the way, function as a rotation stopper on the shaft body 83, thus
stopping rotation of the elastic member.
[0011] There is no protrusion in a region of a circumferential
surface of the roller base body 85 that opposes the driven roller
84, and the elastic member contracts evenly in this region. As a
result, the elastic member is formed into a substantially perfectly
circular shape the cross section of which at a circumference that
contacts the driven roller 84 is acceptable.
RELATED ART DOCUMENTS
Patent Documents
[0012] [Patent Document 1] Japanese Patent No. 4,438,954
[0013] However, reliably stopping the rotation of the elastic
member relative to roller and providing a substantially perfectly
circular cross section may be difficult to accomplish with the
structure taught by Patent Document 1. For example, when a deeper
groove is cut to obtain a greater rotation stopping effect by means
of the rotation stopper, contraction of the elastic member near the
groove becomes larger, and the cross section of the roller will
eventually deviate from the perfectly circular shape.
SUMMARY OF THE INVENTION
[0014] One or more embodiments of the present invention relate to a
conveyance roller that can, for example, reliably stopping the
rotation of an elastic member relative to the roller and provide a
substantially perfectly circular cross section.
[0015] In one aspect, a conveyance roller according to one or more
embodiments of the present invention may comprise a shaft body
having a rotational axis, a roller base body (or simply "roller
base"), which may be of cylindrical shape, and an elastic member
covering the roller base body. The shaft body may comprise the
roller base body. The roller base body has a center axis coinciding
with the rotational axis of the shaft body. The roller base body
may comprise at least one protrusion provided on at least one
lateral surface other than a circumferential surface of the roller
base body and covered by the elastic member. Alternatively, instead
of the at least one protrusion, according to one or more
embodiments of the present invention, the roller base body may
comprise one or more through-holes, into which the elastic member
may be inserted. The one or more through-holes may penetrate the
roller base body, for example in a direction parallel to a diameter
thereof. According to one or more embodiments of the present
invention, the roller base body may comprise one or more radially
extending through-holes, into which the elastic member may be
inserted.
[0016] According one or more embodiments of the conveyance roller,
the at least one protrusion is described as alternative to the at
least one through-hole. However, according to one or more
embodiments of the conveyance roller, the roller base body may
comprise both at least one protrusion provided on at least one
lateral surface other than a circumferential surface of the roller
base body and covered by the elastic member, and at least one
through-hole penetrating the roller base body in a direction
parallel to a diameter thereof and into which the elastic member is
inserted.
[0017] According to one or more embodiments of the conveyance
roller, an effect of stopping the rotation of the elastic member
relative to the roller can be obtained by the at least one
protrusion and/or the at least one through-hole.
[0018] According to one or more embodiments, because the at least
one protrusion may be disposed on the lateral surface other than
the circumferential surface of the roller base body, the at least
one protrusion may have various shapes and heights to stopping
rotation without impairing the circular shape of a cross section of
the roller. According to one or more embodiments, more than one
such protrusion may be provided on the lateral surface other than
the circumferential surface of the roller base body.
[0019] According to one or more embodiments, when the roller base
body is provided with at least one through-hole, because a
thickness of a thick portion decreases, shape irregularities in the
roller base body due to contraction of the elastic member, which
may for example be made of resin, can be suppressed. Since the
roller base body covered by the elastic member is formed into a
more accurate true cylindrical shape, the cross section of the
roller at the roller base body covered by the elastic member is
formed into a more accurate true circular shape.
[0020] In this manner, for example, a conveyance roller capable of
providing both the effect of stopping rotation of the elastic
member relative to the roller and of having a true circular-shaped
cross section can be obtained.
[0021] According to one or more embodiments, the roller base body
may be produced separate from the shaft body and, subsequently, the
roller base body and the shaft body may be mechanically connected
to each other. Alternatively, the shaft body and the roller base
body may be formed in one piece.
[0022] According to one or more embodiments, at least one
protrusion may be provided on at least one lateral side of the
roller base body. According to one or more embodiments, the roller
base body may comprise at least two protrusions, namely a first
protrusion, for example provided on a first lateral surface of the
roller base body, and a second protrusion, for example provided on
a second lateral surface of the roller base body. The first and
second protrusions are covered by the elastic member.
[0023] According to one or more embodiments, due to the one or more
protrusions that may be provided on each of the lateral sides of
the roller base body, a greater effect of stopping the rotation of
the elastic member may be obtained.
[0024] According to one or more embodiments, the roller base body
may comprise a plurality of through-holes. The plurality of
through-holes may penetrate the roller base body in a direction
parallel to a diameter of the roller base body and into which the
elastic member may be inserted. According to one or more
embodiments, a thickness between adjacent through-holes among the
plurality of through-holes, a thickness between at least one of the
plurality of through-holes and the circumferential surface closest
to the at least one of the plurality of through-holes, and a
thickness between the at least one of the plurality of
through-holes and the lateral surface may be substantially equal.
For example, these thicknesses may be substantially equal when they
differ, at the most, by 20%, 15%, 10%, 5% or 1% from each
other.
[0025] According to one or more embodiments, because the
thicknesses of the roller base body may be constant, unevenness of
a contraction amount of the elastic member may be further reduced,
and irregularities in the shape of the roller base body due to
contraction of the elastic member may be more effectively
suppressed.
[0026] According to one or more embodiments, a diameter of the at
least one through-hole may be less than or equal to a thickness of
the elastic member at the circumferential surface of the roller
base body.
[0027] According to one or more embodiments, no dent or
irregularity arises on a top surface of the elastic member
positioned above the at least one through-hole by the elastic
member contracting toward an inside of the at least one
through-hole.
[0028] According to one or more embodiments, the at least one
through-hole may be partially or completely filled with the elastic
member.
[0029] According to one or more embodiments, because the entirety
of the through-hole may be filled with the elastic member, a
greater effect of stopping rotation may be obtained.
[0030] According to one or more embodiments, the elastic member may
be outsert molded on the roller base body.
[0031] According to one or more embodiments, the conveyance roller
may comprise the elastic member outsert molded on the roller base
body.
[0032] According to one or more embodiments, the shaft body and the
roller base body may be made of the same material, such as for
example a resin, or may be made of different materials. According
to one or more embodiments, the elastic member may be made of an
elastic resin.
[0033] According to one or more embodiments, the shaft body, the
roller base body and the elastic member may each be made of a
suitable material as known by one of ordinary skill in the art. The
shaft body, the roller base body and the elastic member body may be
also made of different materials.
[0034] According to one or more embodiments, a printing device may
comprise a conveyance roller according to any of the embodiments
defined above. The conveyance roller may comprise a shaft body
having a rotational axis, a cylindrical roller base body, the
center axis of which may coincide with the rotational axis of the
shaft body, and an elastic member that may cover the roller base
body. The roller base body may comprise at least one protrusion
that is covered by the elastic member and that may be provided on
one lateral surface of the roller base body that is not a
circumferential surface of the roller base body and/or at least one
through-hole that may penetrate the roller base body, for example
in a direction parallel to a diameter of the roller base body and
into which the elastic member may be inserted.
[0035] The conveyance roller of the present invention is capable of
providing both the effect of stopping the rotation of the elastic
member relative to the roller and of having a true circular-shaped
cross section.
BRIEF DESCRIPTION OF DRAWINGS
[0036] FIG. 1 is a perspective view illustrating an example of a
printing device according to one or more embodiments.
[0037] FIG. 2 is a perspective view illustrating an example of a
conveyance mechanism of the printing device according to one or
more embodiments.
[0038] FIG. 3 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0039] FIG. 4 is a front view of the example of shaft body of FIG.
3.
[0040] FIG. 5 is a side view of the example of shaft body of FIG.
3.
[0041] FIG. 6 is a perspective view illustrating an example of a
conveyance roller comprising the shaft body of FIG. 3.
[0042] FIG. 7A is a side view illustrating an example of a shaft
body of a conveyance roller according to one or more
embodiments.
[0043] FIG. 7B is a side view illustrating an example of a shaft
body of a conveyance roller according to one or more
embodiments.
[0044] FIG. 7C is a side view illustrating an example of a shaft
body of a conveyance roller according to one or more
embodiments.
[0045] FIG. 8 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0046] FIG. 9 is a side view of the example of shaft body of FIG.
8.
[0047] FIG. 10 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0048] FIG. 11 is a side view of the example of shaft body of FIG.
10.
[0049] FIG. 12 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0050] FIG. 13 is a cross-sectional view of the example of shaft
body of FIG. 12.
[0051] FIG. 14 is a perspective view illustrating an example of a
conveyance roller comprising the shaft body of FIG. 12.
[0052] FIG. 15 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0053] FIG. 16 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0054] FIG. 17 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0055] FIG. 18 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0056] FIG. 19 is a perspective view illustrating an example of a
shaft body of a conveyance roller according to one or more
embodiments.
[0057] FIG. 20 is a perspective view illustrating an example of a
shaft body of a conventional conveyance roller.
[0058] FIG. 21 is a perspective view illustrating an example of a
conventional conveyance roller comprising the shaft body of FIG.
20.
[0059] FIG. 22 is a perspective view illustrating an example of a
shaft body of a conventional conveyance roller.
DETAILED DESCRIPTION OF EMBODIMENTS
[0060] Embodiments of the present invention will be described in
detail below with reference to the drawings. Each embodiment that
will be described below illustrates an example of the present
invention and is provided for mere illustrative purposes. However,
these embodiments can be combined with each other and are not
intended to be limited to the specific combinations of features
disclosed herein. Also, numerical values, shapes, materials,
components, disposition positions and connection modes of the
components, and the like are examples and are not intended to limit
the present invention.
[0061] A conveyance roller according to one or more embodiments of
the present invention may be a conveyance roller comprising: a
shaft body comprising a cylindrical roller base body having a
center axis coinciding with a rotational axis of the shaft body,
and an elastic member covering the roller base body. According to
one or more embodiments, the rotation of the elastic member
relative the roller base body may be stopped, while maintaining a
substantially perfect circular shape of a cross section of the
roller. The conveyance roller may be used, for example, for
conveying a recording medium, for example in printing devices.
[0062] First, a printing device comprising a conveyance roller
according to one or more embodiments of the present invention will
be described, and afterward the conveyance roller will be described
in detail.
[0063] FIG. 1 is a perspective view showing an example of a
printing device comprising a conveyance roller according to one or
more embodiments of the present invention.
[0064] A printing device 100 illustrated in FIG. 1 comprises an
enclosure body 101. The enclosure body 101 may comprise a feed and
discharge tray 102 for feeding the recording medium before printing
and for receiving the recording medium after printing,
respectively. The recording medium may be, for example, normal
paper, photographic paper, a plastic film, or any other printable
medium. A front surface of the enclosure body 101 may further
comprise a control unit or controller 103 for performing various
types of operations selected by a user.
[0065] FIG. 2 is a perspective view showing an example of a
structure of a main portion of the printing device 100. In FIG. 2,
a conveyance mechanism 200, located inside the enclosure body 101,
and the feed and discharge paper tray 102 are shown. The conveyance
mechanism 200 may feed, transfer, and discharge the recording
medium.
[0066] The conveyance mechanism 200 shown in FIG. 2 may comprise a
frame 201. The frame 201 may comprise, along with the printing
mechanism (not shown), a pick roller 202 for pulling in the
printing medium from the feed and discharge paper tray 102 before
printing; a feed roller 203 for sending the recording medium to a
position where it will be printed; a discharge roller 204 for
discharging the recording medium after printing to the feed and
discharge paper tray 102; and a motor 205 that drives the pick
roller 202, the feed roller 203, and the discharge roller 204.
[0067] The conveyance roller according to one or more embodiments
of the present invention can be used, for example, as a discharge
roller of a printing device, for example the discharge roller 204
of the exemplary printing device 100. The use of the conveyance
roller according to one or more embodiments of the present
invention, however, is not limited to a discharge roller. According
to one or more embodiments of the present invention, the conveyance
roller may also be used as a pick roller or as a feed roller, for
example the pick roller 202 or the feed roller 203 described
above.
[0068] The conveyance roller according to one or more embodiments
of the present invention will be described in detail below.
[0069] FIG. 3 is a perspective view showing an example of a shaft
body and a roller base body of the conveyance roller according to
one or more embodiments of the present invention.
[0070] A shaft body 10 shown in FIG. 3 has a rotational axis
parallel to an x-axis. The shaft body 10 of FIG. 3 has a circular
cross section. However, other cross sections are possible. A roller
base body 11 of cylindrical shape has a center or cylinder axis
coinciding with the rotational axis of the shaft body 10. One or
more protrusions 12 are provided on at least one lateral surface of
the cylindrical roller base body 11. The lateral surface is
distinct from a circumferential surface. For example, the lateral
surface of the roller base body 11 corresponds to a bottom surface
of the cylindrical roller base body 11 and is represented by a
surface parallel to a y-z plane in the example of FIG. 3. According
to one or more embodiments of the present invention, the shaft body
10 and the roller base body 11 may be made of a resin or other
suitable materials and may be formed by injection molding or other
suitable manufacturing methods. However, the shaft body 10 and the
roller base body 11 may be made of different materials.
[0071] FIG. 4 is a front view showing the shaft body 10 in a
y-direction. As illustrated in FIG. 4, at least one or more
protrusions 12 may be provided on both lateral surfaces of the
roller base body 11.
[0072] FIG. 5 is a side view showing the shaft body 10 in an
x-direction. As illustrated in FIG. 5, on the lateral surface of
the roller base body 11, four protrusions 12 of a rectangular
parallelepiped shape extending in a radial direction and orthogonal
to each other may be provided.
[0073] FIG. 6 is a perspective view showing an example of the
conveyance roller according to one or more embodiments of the
present invention.
[0074] On a conveyance roller 1 illustrated in FIG. 6, an elastic
member 30 that covers the roller base body 11 may be formed. The
elastic member 30 may be made of an elastic resin and formed on a
periphery of the roller base body 11 by outsert molding, but other
material and/or manufacturing method may be used. The roller base
body 11 covered by the elastic member 30 may function as a roller,
after the elastic member 30 is solidified by cooling. Moreover, the
protrusion 12, by fitting with the solidified elastic member 30,
may function as a rotation stopper provided on the shaft body 10,
thus stopping rotation of the elastic member 30.
[0075] According to one or more embodiments, because there is no
unevenness on the circumferential surface of the roller base body
11, the elastic member 30 has an even thickness on the
circumferential surface of the roller base body 11 and contracts
evenly. As a result, a cross section of the roller at the roller
base body 11 covered by the elastic member 30 can have a
substantially perfectly circular shape.
[0076] Furthermore, because the protrusion 12 may be disposed on
the lateral surface of the roller base body 11, any number of
protrusions 12 of a shape and height suitable to stop rotation may
be provided without impairing the circular shape of the cross
section of the roller, thus enabling the conveyance roller to
convey an object such as paper with high precision.
[0077] As a result, the conveyance roller according to one or more
embodiments can convey an object such as paper with high
precision.
[0078] An example where four protrusions 12 of a cubic shape are
provided on one lateral surface of the roller base body 11 is
illustrated above, but the number and the shape of the protrusions
shall not be limited to this example. Several other examples where
the number and the shape of the protrusions differ will be
described below.
[0079] For example, as shown in each side view of FIG. 7A, FIG. 7B,
and FIG. 7C, one, two, or three protrusions 12 may be provided on
the lateral surface of the roller base body 11.
[0080] Furthermore, for example, as shown in the perspective view
of FIG. 8 and the side view of FIG. 9, a protrusion 13 may be
shaped as a semicircular column of a quarter sphere of the same
diameter.
[0081] Furthermore, for example, as shown in the perspective view
of FIG. 10 and the side view of FIG. 11, two of the four
protrusions 12, illustrated in FIG. 5, may be replaced with
protrusions 14 of a shape comprising a plurality of branches
extending in a direction orthogonal to a diameter.
[0082] A height from the lateral surface of the roller base body 11
of these protrusions is not limited, but as an example, these
protrusions may be provided at a height greater than or equal to a
thickness of the elastic member 30 on the lateral surface of the
roller base body 11. A higher protrusion may be provided for
enhancing the effect of stopping rotation without adversely
affecting the substantially perfectly circular shape of the cross
section of the roller.
[0083] Furthermore, a root or base of the at least one protrusion
may be greater than or equal to a height commensurate with the
advantageous effect of stopping rotation and covered by the elastic
member 30. The at least one protrusion may not be covered by the
elastic member 30 as long as sufficient stopping of rotation is
provided. In other words, only a portion of the at least one
protrusion may be covered by the elastic member 30. For example, an
apex of the at least one protrusion may not be covered by the
elastic member.
[0084] The conveyance roller according to one or more embodiments
of the present invention may also comprise one or more
through-holes instead of the one or more protrusions to provide
both stopping of rotation of the elastic member relative the roller
base body and a substantially circular-shaped cross section of the
roller.
[0085] When one or more through-holes are defined in the roller
base body, as for example in the exemplary embodiments described
below, the conveyance roller 1 according to one or more embodiments
may have a regular shape due to the reduction of the irregularities
in the shape that may arise due to contraction of the resin in the
roller base body 11 having the comparatively large thickness, and
may comprise an accurately formed roller base body 11 having a
substantially perfectly cylindrical shape.
[0086] Next, a conveyance roller in accordance with one or more
embodiments of the present invention will be described.
[0087] FIG. 12 is a perspective view showing an example of a shaft
body of the conveyance roller according to one or more embodiments
of the present invention.
[0088] A conveyance roller may comprise a shaft body 20 as
illustrated in FIG. 12 having a rotational axis parallel to the
x-axis and a roller base body 21 of a cylindrical shape the center
or cylinder axis of which coincides with the rotational axis of the
shaft body 20. The shaft body 20 of FIG. 12 has a cross-shaped
cross section. However, other cross sections are possible. The
roller base body 21 may comprise one or more through-holes 22, that
for example penetrate the roller base body 21 in a direction
parallel to a diameter thereof. However, the one or more
through-holes 22 may be defined in a radial direction in the roller
base body 21. Independently from the direction, number and form of
the through-holes, the shaft body 20 and the roller base body 21
may be formed in one piece. For example, the shaft body 20 and the
roller base body 21 may be made of a resin, for example by
injection molding, but other suitable materials and/or
manufacturing methods may be used. The shaft body 20 and the roller
base body 21 may also be made of a first and a second material,
respectively.
[0089] Providing at least one through-hole 22 in the roller base
body 21 can reduce the thickness of the roller base body 21,
thereby preventing irregularities in the shape of the roller base
body 21, which are caused in the prior art rollers by uneven
contraction of the resin, without requiring adjustment of the
molding parameters.
[0090] FIG. 13 is a cross-sectional view of the AA cross section of
the roller base body 21 illustrated in FIG. 12 viewed in the
direction of the arrows.
[0091] In FIG. 13, a thicknesses of a thick portion of the roller
base body 21, a thickness a between adjacent through-holes 22, a
thickness b between each through-hole 22 and a circumferential
surface of the roller base body 21, and a thickness c between each
through-hole 22 and a lateral surface of the roller base body 21
are illustrated.
[0092] For example, the through-holes 22 may be provided such that
these thicknesses a, b, c are substantially equal to each other. By
doing so, because the material distribution of the roller base body
21 becomes uniform, unevenness due to a contraction of the resin
can be further reduced, and any irregularity of the shape of the
roller base body 21 due to a contraction of the resin can be more
effectively suppressed.
[0093] FIG. 14 is a perspective view illustrating an example of a
conveyance roller according to one or more embodiments of the
present invention, for example a conveyance roller comprising the
shaft body 20 and the roller base body 21 of FIG. 12. However,
further examples of conveyance rollers having the appearance of the
conveyance roller of FIG. 14 may comprise different through-holes
in terms of number, shape and/or direction and/or may have
different thicknesses a, b and c.
[0094] According to the exemplary conveyance roller 2 illustrated
in FIG. 14, the elastic member 30 may cover or enclose the roller
base body 21 and may enter the at least one through-hole 22. The
elastic member 30 may be made by outsert molding the elastic member
on the roller base body 21 and inside the through hole 22, or by
other suitable manufacturing methods. The roller base body 21
covered by the elastic member 30 may function as a roller, after
the elastic member 30 is solidified by cooling. Moreover, by
fitting the solidified elastic member 30 in the at least one
through-hole 22, rotation of the elastic member 30 relative to the
shaft body 20 may be stopped.
[0095] To stop rotation between the elastic member 30 and the
roller base body 21, the elastic member 30 may enter the at least
one through-hole 22 to a limited depth only, or may completely fill
the at least one through-hole 22.
[0096] According to one or more embodiments, the roller base body
21 in which the at least one through-hole 22 is defined, when
covered by the elastic member 30, has a more accurate truly
cylindrical shape. As a result, the cross section of the roller at
the roller base body 21 covered or enclosed by the elastic member
30 can be formed into a substantially perfectly circular shape.
Moreover, the elastic member 30 at least partially extending into
the at least one through-hole 22 can stop rotation.
[0097] To avoid a dent or any other irregularity in the surface of
the elastic member 30 in the area where the elastic member 30
extends into the at least one through-hole 22, the at least one
through-hole 22 may have a small diameter. For example, the
diameter of the at least one through-hole 22 may be smaller than
the thickness of the elastic member 30 at the circumferential
surface of the roller base body 21.
[0098] However, even when the diameter of the at least one
through-hole 22 is small, by completely filling the at least one
through-hole 22 with the elastic member 30, and fitting the elastic
member 30 in the entirety of the at least one through-hole 22,
improved rotation stopping may be obtained. Moreover, even when the
diameter of the at least one through-hole 22 is small, by providing
multiple through-holes 22, improved rotation stopping may be
obtained, thus enabling the conveyance roller to convey an object
such as paper with high precision.
[0099] As a result, the conveyance roller according to one or more
embodiments can convey the object such as paper with high
precision.
[0100] Although FIGS. 12 and 13 show conveyance rollers with two
through-holes 22 of cylindrical shape in the roller base body 21,
the number and shape of the through-holes shall not be not limited
by this example. Several additional examples with differing numbers
and shapes of through-holes will be described below. For example,
only one through-hole may be provided in the roller base body.
According to further examples, two, three, four or more
through-holes may be provided in the roller base body.
Independently from the number of through-holes, the one or more
through-holes may have a hexagonal cross section, a pentagonal, a
square cross section, a triangular cross section or a circular
cross section may be provided.
[0101] For example, as shown in the perspective view of FIG. 15,
two through-holes 23, for example of a hexagonal column shape, may
be provided in the roller base body 21.
[0102] Furthermore, for example, as shown in the perspective view
of FIG. 16, four through-holes 24, for example of a square column
shape, with chamfered edges may be provided in the roller base body
21.
[0103] Furthermore, for example, as shown in the perspective view
of FIG. 17, a single through-hole 25, for example of a square
column shape, may be provided in the roller base body 21.
[0104] Furthermore, for example, as shown in the perspective view
of FIG. 18, four through-holes 26, for example of a square column
shape, may be provided in the roller base body 21.
[0105] Furthermore, for example, as shown in the perspective view
of FIG. 19, three through-holes 27, for example of a square column
shape, may be provided in the roller base body 21 at irregular
orientations and dispositions.
[0106] The present invention is not limited to the above-described
embodiments. To an extent that they do not depart from the scope of
the claims, embodiments based on various modifications of the
features of the exemplary embodiments described therein or on
various combinations of the different embodiments described therein
are also possible.
[0107] According to one or more embodiments of the present
invention, the conveyance roller may be applied widely to various
types of conveyance mechanisms for conveying an object, such as a
conveyance mechanism of a printing medium in a printing device, for
example. [0108] Although the disclosure has been described with
respect to only a limited number of embodiments, those skilled in
the art, having benefit of this disclosure, will appreciate that
various other embodiments may be devised without departing from the
scope of the present invention. Accordingly, the scope of the
invention should be limited only by the attached claims.
EXPLANATION OF REFERENCE NUMBERS
[0109] 1, 2, 8 Conveyance roller
[0110] 10, 20, 80, 83 Shaft body
[0111] 11, 21, 81, 85 Roller base body
[0112] 12 to 14, 82 Protrusion
[0113] 22 to 27 Through-hole
[0114] 30, 91 Elastic member
[0115] 84 Driven roller
[0116] 86 Groove
[0117] 87 Step
[0118] 92 Protuberance
[0119] 100 Printing device
[0120] 101 Enclosure body
[0121] 102 Feed and discharge paper tray
[0122] 103 Control unit (or controller)
[0123] 200 Conveyance mechanism
[0124] 201 Frame
[0125] 202 Pick roller
[0126] 203 Roller
[0127] 204 Discharge roller
[0128] 205 Motor
* * * * *