Information
-
Patent Grant
-
6666597
-
Patent Number
6,666,597
-
Date Filed
Wednesday, October 31, 200122 years ago
-
Date Issued
Tuesday, December 23, 200320 years ago
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Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 400 223
- 400 207
- 400 208
- 400 2081
- 400 221
- 400 2211
- 400 2212
- 400 230
- 400 236
- 400 2361
- 400 2362
- 400 242
- 400 307
- 400 3071
- 400 3072
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International Classifications
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Abstract
A geared drive hub assembly for a printer cartridge containing a geared drive hub removably engaged with a spool. The geared drive hub contains a gear and a base connected to the gear; the base is integrally connected to a first stepped spline, a second stepped spline, and a third stepped spline. The spool contains a device for engaging each of the stepped splines.
Description
FIELD OF THE INVENTION
A geared drive hub assembly for a printer cartridge containing a geared hub drive removably engaged with a spool.
BACKGROUND OF THE INVENTION
U.S. Pat. No. 6,161,972 of Kameyama Yoshikatsu discloses an ink ribbon cartridge having a particular spool and spindle arrangement. The spindles used in the device of this patent each have one end which includes a disk shaped section, and a spindle portion 64 which includes projections 65 and 66 disposed 150 degrees apart from each other (see FIGS. 11 and 12).
The spindles disclosed in U.S. Pat. No. 6,161,972, although they have some limited utility when used with the spools disclosed in such patent, cannot readily be used with other spools. Furthermore, they tend to fail when more than a minimal amount of shear force is applied to the projections 65 and 66 and, in general, have inferior mechanical properties.
It is an object of this invention to provide a novel spindle which can be used with many different spools and which has improved mechanical properties.
SUMMARY OF THE INVENTION
In accordance with this invention, there is provided a geared drive hub assembly removably engaged with a spool. The drive hub contains a gear integrally connected to a spindle assembly. The spindle assembly contains three stepped splines integrally connected to each other and to a base; and the spool is comprised of means for removably engaging each of the three stepped splines.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described by reference to the following drawings, in which like numerals refer to like elements, and in which:
FIG. 1
is a perspective view of a printer cartridge comprised of the geared drive hub of this invention.
FIG. 2A
is a side view of the geared hub drive of
FIG. 1
engaged a spool;
FIG. 2B
is a first end view of the assembly of
FIG. 2A
;
FIG. 2C
is a partial sectional view of the assembly of
FIG. 2A
;
FIG. 2D
is a partial sectional view of the assembly of
FIG. 2A
;
FIG. 2E
is a sectional view of the assembly of
FIG. 2A
;
FIGS. 3A
to
3
F each present a schematic representation of how the geared drive hub depicted in
FIG. 2A
may be used with different spools to produce different assemblies; and
FIG. 4
is a front view of the geared drive hub depicted in FIG.
2
.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1
is a perspective view of a printer cartridge
10
comprising gear drive hub
12
operatively connected to a spool
16
The gear drive hub
12
is comprised of a gear
14
which, when the cartridge
10
is disposed within a printer, is engaged by another gear (not shown) and caused to rotate.
In recent years, printers have become faster and faster, in response to consumer demand. The faster the printer, the faster gear
14
must turn, and the more torque that is applied to such gear
14
, its component parts, and the spool
16
with which it is operatively engaged. The geared drive hub
12
is well suited to cope with the increased stresses and strains imposed by the use of modern printers.
In the preferred embodiment depicted in
FIG. 1
, the spool
16
is preferably constructed from a plastic material. The use of such a plastic spool eliminates the possibility of contaminating the printer ribbon (not shown) with particles of cardboard material from the cardboard spool commonly used in prior art devices.
In one embodiment, spool
16
consists essentially of plastic material. One may use plastics such as, e.g., acrylonititrile/butadiene/styrene (ABS), polystyrene, “DELRIN” (an acetal resin manufactured by the Du Pont de Nemours E.I. & Company of Wilmington, Del.), and the like.
FIG. 2A
is a side view of one preferred geared drive hub
12
of the invention. Referring to
FIG. 2A
, and in the preferred embodiment depicted therein, it will be seen that gear drive hub
12
is comprised of gear
14
which is connected by means of shaft
17
to the base
18
of the gear drive hub
12
.
Connected to base
18
, and preferable integrally connected to base
18
, is splined section
20
. Splined section
20
is preferable comprised of a multiplicity of stepped splines.
As is known to those skilled in the art, a spline is a device which permits the transmission of rotation or translatory motion along the axis of a shaft. Reference may be had, e.g., to U.S. Pat. Nos. 6,152,913, 5,620,427, 4,688,478, 4,237,750, and the like. The entire disclosure of each of these United States patents is hereby incorporated by reference into this specification.
The splined section
20
preferable contains three stepped splines. Without wishing to be abound to any particular theory, applicants believe that the use of such three stepped splines affords their claimed structure umproved stability, better concentricity around the rotational axis of the gear splined hub, better distribution of torque, and better accuracy. With the high-speed printers commonly in use today, these features are especially important.
Referring again to
FIG. 2A
, one of the stepped splines, stepped spline
22
, is shown on the gear splined hub
12
. As will be apparent, stepped spline
22
is comprised of a lower section
24
communicating with an upper section
26
.
FIG. 2B
is an end view of geared drive hub
12
, taken facing upper section
26
(see
FIG. 2A
) and illustrating splined assembly
20
and the stepped splines
22
,
28
, and
30
which comprise such splined assembly
20
. This Figure is not to scale, having been enlarged for the sake of simplicity of representation.
As will be apparent, and in the preferred embodiment depicted in
FIGS. 2A and 2B
, stepped splines
22
,
28
, and
30
are integrally connected to a central portion
32
to provide one integral assembly.
In the preferred embodiment depicted in
FIG. 2B
, arcuate sections
34
,
36
, and
38
are disposed, respectively, between stepped splines
22
and
28
,
28
and
30
, and
30
and
22
, respectively. These arcuate sections are commonly referred to as fillets.
Without wishing to be bound to any particular theory, applicants believe that the use of fillets
34
,
36
, and
38
provide a stronger splined assembly
20
.
FIG. 2C
is a sectional view of a spool
16
which may be used with the geared drive hub
12
depicted in
FIGS. 2A and 2B
. The upper section
26
of gear drive hub
12
(see
FIG. 2A
) is inserted into end
40
of spool
16
and, in particular, is disposed within receptacle
42
in which the stepped splines
22
,
28
, and
30
(see
FIG. 2C
) are engaged within such receptacle
42
.
FIG. 2D
is an end view of the spool
16
, indicating the cross-sectional shape of one embodiment of the receptacle
42
with which the splines
22
,
28
, and
30
engage.
FIG. 2E
is a sectional view of the gear drive hub
12
disposed within the spool
16
.
The stepped spline structure depicted in
FIG. 2B
preferably has stepped splines
22
,
28
, and
30
disposed equidistantly about centerpoint
33
, located about 120 degrees from each other. This preferred stepped spline structure not only is capable of engaging the cross-sectional shape of receptacle
42
, but it is also capable of engaging with the cross sectional shapes depicted in
FIG. 3 and
, in particular,
FIGS. 3A
,
3
B,
3
C,
3
D,
3
E, and
3
F. Other cross-sectional shapes with which such splines may engage will be apparent to those skilled in the art.
FIG. 4
is a sectional view of one preferred embodiment of geared drive hub
12
. In the preferred embodiment depicted in
FIG. 4
, it will be seen that gear
14
has a thickness
50
of 0.16 inches, base
18
has a diameter
52
of 0.7 inches and a thickness
53
of 0.04 inches, the overall length
54
of geared drive hub
12
is 1.485 inches, the distance
56
between end
27
of the geared hub drive
12
and the top surface
29
of base
18
is 0.545 inches, and the distance
58
between the bottom surface
31
of the base
18
and the end
33
of upper spline section
36
is 0.5 inches.
It is to be understood that the aforementioned description is illustrative only and that changes can be made in the apparatus, in the ingredients and their proportions, and in the sequence of combinations and process steps, as well as in other aspects of the invention discussed herein, without departing from the scope of the invention as defined in the following claims.
Claims
- 1. A geared drive hub assembly for a printer cartridge comprised of a geared drive hub removably engaged with a spool, wherein:(a) said geared drive hub is comprised of a gear and a base connected to said gear, wherein said base is integrally connected to a first stepped spline, a second stepped spline, and a third stepped spline, and (b) said spool is comprised of means for engaging said first stepped spline, said second stepped spline, and said third stepped spline.
- 2. The geared drive hub assembly as recited in claim 1, wherein said spool consists essentially of plastic material.
- 3. The geared drive hub assembly as recited in claim 1, wherein said geared drive hub is comprised of a shaft.
- 4. The geared drive hub assembly as recited in claim 1, wherein said shaft is disposed between and connected to each of said gear and said base.
- 5. The geared drive hub assembly as recited in claim 1, wherein a first fillet is disposed between said first stepped spline and said second stepped spline, a second fillet is disposed between said second stepped spline and said third stepped spline, and a third fillet is disposed between said third stepped spline and said first stepped spline.
- 6. The geared drive hub assembly as recited in claim 1, wherein said base has a substantially cylindrical cross-sectional shape.
- 7. The geared drive hub assembly as recited in claim 6, wherein said base is comprised of a centerpoint.
- 8. The geared drive hub assembly as recited in claim 7, wherein said first stepped spline, said second stepped spline, and said third stepped spline are disposed substantially equidistantly around said centerpoint.
- 9. The geared drive hub assembly as recited in claim 1, wherein each of said first stepped spline, said second stepped spline, and said third stepped spline is comprised of a lower section communicating with an upper section.
- 10. The geared drive hub assembly as recited in claim 9, wherein said spool has a substantially cylindrical shape.
US Referenced Citations (9)