U.S. patent application number 10/370391 was filed with the patent office on 2003-08-21 for abrasive finishing devices.
Invention is credited to Machlitt, Michael, Stein, Bernd, Stief, Christian, Vankov, Michael.
Application Number | 20030157872 10/370391 |
Document ID | / |
Family ID | 27674770 |
Filed Date | 2003-08-21 |
United States Patent
Application |
20030157872 |
Kind Code |
A1 |
Vankov, Michael ; et
al. |
August 21, 2003 |
Abrasive finishing devices
Abstract
An abrasive device includes at least two abrasive tracks
disposed on a support portion, the abrasive tracks having abrasive
surfaces with abrasive elements. The abrasive device may be used to
perform various abrasive processes either consecutively or in
parallel by means of different abrasive surfaces.
Inventors: |
Vankov, Michael; (Schmitten,
DE) ; Stein, Bernd; (Schmitten, DE) ; Stief,
Christian; (Frankfurt am Main, DE) ; Machlitt,
Michael; (Schwalbach, DE) |
Correspondence
Address: |
FISH & RICHARDSON PC
225 FRANKLIN ST
BOSTON
MA
02110
US
|
Family ID: |
27674770 |
Appl. No.: |
10/370391 |
Filed: |
February 19, 2003 |
Current U.S.
Class: |
451/540 |
Current CPC
Class: |
A46D 9/02 20130101 |
Class at
Publication: |
451/540 |
International
Class: |
B24D 017/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 20, 2002 |
DE |
102 07 071.7 |
Claims
What is claimed is:
1. An abrasive device comprising: a support portion; and a disc
portion, wherein the disc portion comprises a first abrasive track
having a first abrasive surface, and a second abrasive track having
a second abrasive surface, wherein the abrasive surfaces comprise
abrasive elements.
2. The abrasive device of claim 1, further comprising a step
disposed between the first abrasive track and the second abrasive
track.
3. The abrasive device of claim 1, wherein the abrasive surface of
at least one abrasive track is cambered or arched.
4. The abrasive device of claim 1, wherein the abrasive elements of
each abrasive track comprise different materials.
5. The abrasive device of claim 1, wherein the abrasive elements of
each abrasive track define different sizes or shapes.
6. The abrasive device of claim 1, wherein the disc portion
comprises a flat or curved surface with a radially inner area on
which a first round abrasive track is disposed, and a peripheral
area on which a second annular abrasive track is disposed.
7. The abrasive device of claim 6, wherein at least one abrasive
surface defines the lateral surface of an inverted cone or inverted
truncated cone, having a center point which passes through a center
of rotation of the abrasive support portion.
8. The abrasive device of claim 1, wherein the abrasive device is
in the form of a circulating band or circulating roller, upon which
the abrasive tracks are disposed and are laterally adjacent.
9. The abrasive device of claim 1, wherein the rotating speeds of
the abrasive surfaces are modified to match those of the abrasive
tracks.
10. A method for finishing the ends of bristle tuft filaments,
comprising: (a) providing a rotating disc including at least two
abrasive tracks with abrasive surfaces having different abrasive
properties, each abrasive surface comprising corresponding abrasive
elements; (b) contacting an end of a bristle tuft with the first
abrasive track to perform a first finishing process; and then (c)
contacting the end of the bristle tuft with the second abrasive
track to perform a second finishing process.
11. The method of claim 10, wherein the abrasive tracks are
disposed at different distances from the rotational center of the
disc.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to German Patent
Application No. DE 102 07 071.7, filed Feb. 20, 2002, which is
incorporated herein by reference in its entirety.
TECHNICAL FIELD
[0002] The invention relates to an abrasive device for finishing
the ends of bristle filaments.
BACKGROUND
[0003] U.S. Pat. No. 3,451,173 A discloses an abrasive device for
preparing the ends of bristle filaments. The outer surface of an
outwardly curved disc includes an abrasive surface, against which
bristle tuft ends are pressed. As the disc rotates, the tufts move
transversely to the disc, and the tuft ends are pressed against the
abrasive surface. In this way, the tuft ends are worn down by
contact with the roughness of the abrasive surface, or are finished
by some other mechanical method. The various abrasive processes are
executed by sequentially arranged abrasive units. This type of
arrangement is awkward and expensive because after the initial
rounding process, a transport means must transport each tuft to the
next abrasion process. Such an apparatus also requires a great deal
of space.
[0004] German Patent No. DE 198 48 221 A1 discloses an abrasive
device for finishing the ends of bristle filaments of toothbrushes,
in which an abrasive surface is conformed to the outer peripheral
surface of a drum. Two different abrasive surfaces are provided on
the periphery of a lateral surface. The first abrasive surface
forms a strip-like track extending in the direction of rotation.
The second abrasive surface interrupts the first abrasive surface,
and includes projections or ridges that run transversely to the
first abrasive surface. As the first abrasive surface rounds the
bristle ends, the second abrasive surface roughens the bristles'
directly adjacent lateral surfaces, thereby increasing the size of
the active polishing surface. Thus, the bristles' frontal
extremities and lateral surfaces are finished alternatingly in a
single abrasion process, and as frequently in a single revolution
as there are protrusions and trace sections on the peripheral
abrasion surface of the disc.
SUMMARY
[0005] In one aspect, the invention features an abrasive device
including a support portion and a disc portion. The disc portion
has a first abrasive track with a first abrasive surface and a
second abrasive track with a second abrasive surface. The abrasive
surfaces include abrasive elements.
[0006] In some embodiments, the individual abrasive surfaces are
clearly differentiated from one another, such that the abrasive
processes are clearly separated.
[0007] In other embodiments, there is a gradation from one surface
to the next. If the ends of the bristle filaments lie in one plane,
then as the change is made from one abrasive surface to the other,
the contact pressure of the bristle filament ends on the friction
discs or bands is reduced or increased automatically in the second
abrasion operation, according to the shape of the gradation. This
change in contact pressure occurs because the distance between the
ends of the bristle filaments and the second abrasive surface has
either increased or decreased relative to the distance from the
first abrasive surface. Thus, it is not necessary to employ
expensive pressure maintenance devices for the bristle filaments.
With a rotating disc, it is advantageous if the steps proceed
radially towards the center of the disc.
[0008] In some embodiments, the abrasive surface of at least one
abrasive track is inclined or cambered or arched. Several abrasive
surfaces may be inclined or cambered without a step being formed.
Friction surfaces extending transversely to the bristle filaments
may also be formed by the camber. If the bristles extend
perpendicularly to the first abrasive surface, then the contact
pressure decreases from the first abrasive surface to the second
abrasive surface, if the second abrasive surface is inclined toward
the bristle tufts. Such an arrangement may be advantageous in the
subsequent polishing process.
[0009] In some embodiments, the abrasive device has different
abrasive surfaces on its various abrasive tracks because of
different grain sizes, materials, or shapes. Different abrasive
processes may be performed by the use of different abrasive
elements. The different abrasive elements may be used either one
after the other, or side-by-side.
[0010] In some cases, an abrasive disc preferably has two abrasive
tracks, so that two abrasive processes may be executed either
synchronously or sequentially. In other cases, three, four, or even
more abrasive tracks may be present on the abrasive disc, if a
corresponding number of abrasive processes are to be executed and
sufficient space is provided on the abrasive disc to accommodate
the bristles and the tufts. The diameter of the abrasive disc is
adapted to accommodate the abrasive tracks. As the diameter of the
abrasive disc is increased, considerably higher friction speeds are
engendered at the perimeter. Consequently, the bristle filaments
may be finished considerably more effectively with coarser disc
surfaces. Toward the center of the abrasive disc, where the
diameters are relatively small, the lower friction speeds allow
finer abrasive processes, such as polishing, to be performed. A
round abrasive disc with circular and annular abrasive tracks has
proven to be especially inexpensive to manufacture.
[0011] In some embodiments, the abrasive disc is formed from a
truncated cone or a cone surface. The different heights of the
abrasive tracks enable varying contact pressures to be exerted on
the bristle filaments. The inclination of the disc must be adapted
to the abrasive surfaces, the friction speed, and the material of
the bristle filaments.
[0012] With regard to the abrading motion, the abrasive device does
not have to rotate only about its own axis. The abrasive device may
also perform tumbling rotations, so that the contact force of the
disc against the bristle ends changes constantly, and both radial
and tangential frictional forces are applied to the bristle ends.
Such an arrangement improves the rounding of the bristle ends. The
rotation of the abrasive disc may also be changed continuously from
left rotation to right rotation, thereby contributing to better
rounding. A combination of all of the properties described results
in the optimal rounding technique.
[0013] In some embodiments, the abrasive device includes a
circulating band or circulating roller on which several abrasive
tracks are disposed side-by-side. Because the diameter remains
constant, the friction speeds are equal on all abrasive tracks.
Where the circulating band or circulating roller is inclined toward
the tuft axis as it passes, the contact pressure against the ends
of the bristle filaments may also be varied.
[0014] In some embodiments, the rotating speed changes with the
change to another abrasive track. As a result, optimal abrasive
processing on the bristle filament ends may be achieved.
[0015] In another aspect, the invention features a method for
finishing the ends of bristle tuft filaments. The method includes
providing a rotating disc with at least two abrasive tracks having
abrasive surfaces with different abrasive properties. Each abrasive
surface includes corresponding abrasive elements. The method
further includes contacting an end of a bristle tuft with the first
abrasive track to perform a first finishing process; and then
contacting the end of the bristle tuft with the second abrasive
track to perform a second finishing process.
[0016] In some embodiments, the abrasive tracks are disposed at
different distances from the rotational center of the disc.
[0017] Implementations of the invention may have one or more of the
following advantages. Multiple abrasion processes may be executed
easily and quickly, and by simple means. Rounding of complex
bristle topographies may be adapted more precisely to an abrasive
process. The abrasive device is simple and can save time and space.
Furthermore, it may be relatively inexpensive.
[0018] Another advantage resulting from an abrasive disc having
several abrasive tracks is that it is possible to begin a second
abrasive pass as soon as a first abrasive pass is completed. Either
the bristle tufts undergo a minor displacement with respect to a
first abrasive surface, or the abrasive disc is displaced with
respect to the bristle tufts. Alternatively, both the bristle tufts
and the abrasive disc may be displaced toward the second abrasive
surface. The abrasive tracks are aligned so that they extend in the
direction of movement of the abrasive disc and/or the bristle tuft
ends.
[0019] In this way, a simple device may economically effect
multiple abrasive passes. For instance, the bristle tuft ends may
be abraded coarsely in a first operation, more finely in a second
operation, even more finely in a third operation, and polished in a
fourth operation. To achieve this, four abrasive tracks would have
to be conformed onto the disc and alternated in sequence once a
previous abrasion operation was completed. It is also possible to
pass over some abrasive tracks if, for example, the inner bristle
tufts of a toothbrush do not have the same high surface area
requirement as the peripheral bristle tufts.
[0020] Some advantages of such an abrasive device are that it
requires relatively little space and that it consumes a relatively
small number of operating materials. Furthermore, the abrasion time
per toothbrush is shorter, since the bristle tufts do not need to
be worked with different abrasive discs for different abrasive
processes. Thus, the cycle time of abrasive processes is
reduced.
[0021] The details of one or more embodiments of the invention are
set forth in the accompanying drawings and the description below.
Other features and advantages of the invention will be apparent
from the description and drawings, and from the claims.
DESCRIPTION OF DRAWINGS
[0022] FIG. 1 is a reduced scale schematic plan view of one
embodiment of an abrasive device.
[0023] FIG. 2 is a cross-section taken through the middle of the
abrasive device of FIG. 1, in which the abrasive surface is
enlarged and the Support portion is only represented in part.
[0024] FIG. 3 is a reduced scale schematic plan view of one
embodiment of an abrasive device.
[0025] FIG. 4 is a cross-section taken through the middle of the
abrasive device of FIG. 3, in which the abrasive surface is
enlarged and the support portion is only represented in part.
[0026] FIG. 5 is a reduced scale schematic plan view of one
embodiment of an abrasive device.
[0027] FIG. 6 is a cross-section taken through the middle of the
abrasive device of FIG. 5, in which the abrasive surface is
enlarged and the support portion is only represented in part.
[0028] FIG. 7 is a reduced scale schematic plan view of one
embodiment of an abrasive device.
[0029] FIG. 8 is a cross-section taken through the middle of the
abrasive device of FIG. 7, in which the abrasive surface is
enlarged and the support portion is only represented in part.
DETAILED DESCRIPTION
[0030] Referring to FIGS. 1-8, an abrasive device 1 includes a
support portion 2 and a disc portion 3. Disc portion 3 includes
abrasive tracks 6 and 7. Abrasive tracks 6 and 7 have abrasive
surfaces 8 and 9, which are adjacent along line 10. Abrasive
surfaces 8 and 9 include abrasive elements 4. Abrasive surfaces 8
and 9 together form an abrasive coating 5.
[0031] FIGS. 1 and 2 show that abrasive surface 9 is in the shape
of an enclosed circle surrounded by abrasive surface 8. The
transition from abrasive surface 9 to abrasive surface 8 at line 10
is practically seamless. Abrasive surfaces 8 and 9 lie in a single
horizontal plane.
[0032] In FIGS. 3 and 4, abrasive surface 8 has a half-moon shape
in the middle of which, however, a semicircle is formed, so that
the remainder of the overall circular abrasive coating 5 is
occupied by abrasive surface 9, in a half circle and ring. Abrasive
surfaces 8 and 9 lie on the same horizontal plane.
[0033] Referring to FIG. 5, abrasive surfaces 8 and 9 appear to
have the same conformation as they do in FIG. 1. However, as shown
in FIG. 6, abrasive surfaces 8 and 9 actually slope toward center
11, so that their lateral surfaces form a uniform V-shaped
surface.
[0034] FIGS. 7 and 8 show abrasive surfaces 8 and 9, with a step 12
at the transition from abrasive surface 8 to abrasive surface 9.
Thus, abrasive surface 9 is lower than abrasive surface 8. However,
it is also possible to reverse step 12 so that abrasive surface 9
is raised above abrasive surface 8. Furthermore, it is possible to
have a sloping ramp in the place of step 12, so that the transition
from abrasive surface 8 to abrasive surface 9 is gradual.
Alternatively, step 12 may be formed by a continuous curve, so that
the transition from abrasive surface 8 to abrasive surface 9
appears continuous.
[0035] Referring now to FIG. 2, a bristle tuft 13 extends
vertically to abrasive surface 8. Bristle tuft 13 consists of
individual bristle filaments 15 that all extend in the longitudinal
direction of bristle tuft 13. As soon as ends 14 of bristle tuft 13
have been sufficiently finished by abrasive surface 8, bristle tuft
13 may be moved to contact second abrasive surface 9.
Alternatively, abrasive support 2 may be driven until ends 14 of
bristle tuft 13 are located on surface 9, and may thus be processed
further. At the same time, the speed of rotation of abrasive device
1 may be increased or reduced to achieve the desired abrasive
effect on the ends 14 of bristle tuft 13.
[0036] In FIGS. 3 and 4, abrasive device 1 is configured such that
it must be rotated in an oscillating manner about its axis 11 (axis
shown in FIG. 6) if bristle tufts 13 are to remain in contact with
only one abrasive surface, 8 or 9.
[0037] FIGS. 5 and 6 show that bristle tufts 13 may be oriented to
extend parallel to center 11. In other words, ends 14 of bristle
tufts 13 may be abraded obliquely, or rounded.
[0038] Referring to FIGS. 7 and 8, abrasive device 1 enables
contact pressure to be reduced when ends 14 of bristle tufts 13 are
moved from outer abrasive surface 8 to inner abrasive surface 9.
Thus, ends 14 may be pressed against surface 9 with less contact
pressure. In such cases, abrasive surface 9 may serve as a
polishing surface.
* * * * *