Note: Descriptions are shown in the official language in which they were submitted.
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SANDING W~IEEL
Technical Field
This invention relates to sandiny wheels of the
type adapted to sand both flat and irregular surfaces,
which wheels store a reserve supply of abrasive~-coated
material in their hub assemblies.
Background Art
Wheels o the type adapted to sand both ~Elat and
irregular surEaces such as may be present on wooden
moldings are described in U.S. Patents Nos. 2,194,577,
2,Al~,966, 2,533,619, 2,713,759 and 3,132,452. Gene~ally
that type of sanding wheel comprises a hub assembly adapted
for engagement by a drive motor to rotate it in a first
direction, a plurality of 1exible support members
(typically in the form of bristle brushes) fixed in the hub
assembly and projecting generally radially outwardly of its
periphery, and a plurality of lengths of flexible
abrasive-coated material, outer end portions of which
extend through slots in the periphery of the hub assembly
and project along the leading sides of the support members
so that when the hub assembly is rotated the projecting
portions of the abrasive-coated material are resiliently
backed by the support members during application thereoE to
a surface to be sanded. Portions of the lengths of
abrasive-coated material are also stored within the hub
assembly and means are provided for releasably securing the
lengths of abrasive-coated material within the hub assembly
so that after the projecting portions of the
abrasive-coated material become dull or wear away, the
means for releasably securing can be temporarily released
so that fresh portions of the lengths of abrasive-coated
material can be pulled through the slots and positioned
along the support members.
In knowrl sanding wheels of the aEorementioned
type, however, the lengths oE abrasive-coated material
~33~;6
each have one end permanently or releasably attached to a
core, and the means for releasably securing the lengths oE
abrasive-coated material releasably loc~s the core in
place within the hub assembly~ While such an app~oach may
be satisfactory for securing the lengths of abrasive-coated
materiai~ the cost of permanently attaching a plurality oE
lengths of abrasive-coated material to a core or adapting
~he lengths of abrasive-coated material to aford their
releasable attachment to a core adds significantly to the
cost of the abrasive-coated material used in the sanding
wheel. Adjusting the position o~ the core adjusts the
position o~ all of the lengths of abrasive-coated material,
which may not be necessary or desirable if the projecting
portion oE only a few of the lengths are dull or worn away.
Fairly large end portions of the lengths of abrasive-coated
m~terial extending from the core to the periphery of the
wheel can never be used, which is wasteful; and the wheels
are generally difficult to reload with new abrasive-coated
- material since typically they must be taken apart for that
purpose.
Disclosure of the Invention
The present invention provides an inexpensive
sanding wheel of the type described above ~or sanding both
flat and irregular surfaces, which sanding wheel is adapted
to use ~ndividual leng~hs of abrasive-coated material which
are not at-tached together or to a core duriny use on the
wheel, but are held adjacent the periphery of the wheel,
thereby minimi~ing the cost of the abrasive-coated material
used in -the wheel; and which lengths of abrasive-coated
30 material can be individually loaded into the wheel wi-thout
taking the wheel apart, and can have their positions
individually adjusted on the wheel so that only dull or
worn away projecting portions need be replaced~
According to the present inv3ntion there is
35 provided a sanding wheel of the type comprising a hub
assembly adapted to be engaged and ro-tated by a drive
6~
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motor in a first direction; a plurality of flexible
support members or brushes having one end Eixed on the hub
assembly and projecting generally radially outwardly o-f
its periphery; and a plurality of lengths of Elexible
abrasive-coated material each extending through a slot in
the hub assembly and being positioned so that its outer
end portion will project along the leading surEace oE one
of the suppor-t members, and having an inner end portion
secured by means within the hub assembly. In the improved
wheel according to the present invention the lengths of
abrasive-coated material are separate and nonconnected,
and the means Eor releasably securing them are located
adjacent the periphery of the hub assembly and a~Eord,
when released, individual positioning, insertion or
removal of the separate lengths of abrasive-coated
material with respect to the hub assembly.
In a preferred embodiment the sanding wheel is
adapted ~or use with len~ths oE abrasive-coated mater;al
having scalloped edges. The hub assembly comprises first
20 and second portions defining a separate internal passage-
way or each of the lengths of abrasive-coated material
with each of the hub portion~ derining a different edye of
each of the passageways adjacent its periphery. The hub
portions have lugs adjacent their periphery adapted to
25 engage between the scallops along the edges of the lengths
of abrasive-coated material alony the passageway, and are
relatively axially movable between a lock position with
the lugs between scallops along the edges of the lengths
oE abrasive-coated material to hold the lengths of
30 abrasive-coated material in the hub assembly, and a
released position spaced to afford free movernent of the
lengths of abrasive-coated material along the passageways
past the lugs. Also the sanding wheel comprises means Eor
releasably holding the hub portions in the lock pOSiti
35 which together with the scalloped edge , relatively
movable hub portions, and the lugs provides the means Eor
releasably securing the lengths of abrasive-coated
3~66
material within the hub assembly.
Alternatively, however, the means Eor releasably
sec~ring the lengths oE abrasive-coated material couLd be
self-locking cams or spring-hiased lock members (whic~ lock
members can pivotably support the support members) located
adjacent the peripery of the hub assembly.
Brief Description oE Drawing
The present invention will be more thoroughly
described with reference to the accompanying drawing
wherein like numbers refer to like parts in the several
views, and wherein:
Figure 1 is a perspective view oE a Eirst
embodiment of a sanding wheel according to the present
invention;
Figure 2 is an inner side view of a Eirst
portion of the sanding wheel shown in Figure l;
Figure 3 is an inner side view of a second
portion of the sanding wheel shown in Figure l;
Figure 4 is a front exploded view of the sanding
wheel shown in Figure l;
Figure S is an enlarged fragmentary sectional
view taken approximately along line 5-S of Figure l;
Figure 6 is a side view of a second alterna-te
embodiment of a sanding wheel according to the present
invention having par-ts broken away to show details; and
Figure 7 is a fragmentary sectional side view of
a third alternate embodiment of a sanding wheel according
to the present invention.
Description oE the Preferred Embodiments
Referring now to the drawing there is shown in
Figures 1 through 5 a first embodiment oE a sanding wheel
according to the present invention yenerally designated by
the reference numeral 10.
Briefly the sanding wheel 10 comprises a hub
assembly 12 from which projects a distal end oE a bolt 14
3~
adapted to be engaged and rotated by a drive motor (not
shown) to rotate the sanding wheel 10 in a first direction
indicated by the arrow in Figure 1, and a plurality o
Elexible support members or brushes 16 each having one end
fixed in the hub assembly 12 and projecting gener~lly
radially outwardly of its peripheral wall or periphery 17.
A plur~lity of individual nonconnected lengths 18 of
flexible abrasive- coated material each extend through a
diEferent slot 20 in the hub assembly 12 and are positioned
so that their outer projecting end portions project along
the surfaces of adjacent ones of the brushes 16 that lead
when the wheel 10 is rotated in the first direction so that
the projecting end portions of the lengths 18 of abrasive
material can be yieldably pressed into abrasive engagement
with a flat or irregular surface by the brushes 16.
As is seen in Figures 1 and 5, the lengths 18 o~
abrasive-coated material with which the wheel 10 is
adapted to be used have scalloped edges 24. The hub
assembly 12 comprises a first portion 26 ~best seen in
20. Figures ?. and 4) and a second portion 28 (best seen in
Figures 3 and 4) which together define a separate helical
passageway 30 for each of the lengths 18 of abrasive-
coated material, with each of the hub portions 26 or 28
defining a different edge of each of the passageways 30.
The portions 26 and 28 have lugs 32 (Figures 2, 3 and 5)
adjacent their peripheries adapted to engage between the
scallops along the edges 24 of the lengths 18 of abrasive-
coated material along the passageways 30, and are re.l.ative-
ly axially movable between a lock position (Figures 1 and
30 5) with the lugs 32 between the scallops to hold the
lengths 18 of abras.ive-coated material in the hub assembly
12, and a released position (not shown) spaced to afford
free manual movement of the lengths 18 of abrasive-coated
material in either direction along the passageways 30 past
35 the lugs 32. Also the sanding wheel 1l) comprises means
including a threaded portion 33 oE the bolt 14 and a
knur].ed nut 34 for releasably holding the hub portions 26
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ancl 28 in the lock position which, together with the
scalloped edges 24, relatively movable hub portion.s 26 an~
28, and the lugs 32 provides the means for releasably
securing the lengths 18 of abrasive-coated material within
the hub assembly 12.
The first and second pcrtions 26 and 28 of the
hub assembly 12 are each generally cylindrical and are
formed, preferably by molding,of a rigid polymeric
materia:l (e.g., ~.B.S., polypropylene, or hi.gh impact
styrene). Each por-tion 26 or 28 has a circular end wall
(36 and 38 respectively), from which end wall 36 or 38
project axially toward the other portion 26 or 28 spaced,
matched guide walls defining therebetween halves of the
helical passageways 30 leading to the slots 20. The first
5 portion 26 has a central through axially-extending opening
40 through ~hich the bolt 14 projects and has a recess 41
around the opening 40 in its end wall 36 adapted to
receive a head 42 on the bolt 14 to prevent rotation of
the bolt 14 relative to the first portion 26. The Eirst
20 portion 26 also includes a pluralit~ of projecting
channel-like parts 44 spaced around its periphery, which
parts 44 are slotted through the peripheral surface 17 and
are open at their distal ends to each receive twhen the
portions 26 and 28 are separated) a base 46 on one of the
25 brushes 16 with bristles on the brush 16 projecting
through a portion of the slot at the periphery 17 which is
sufficiently narrow to preclude passage of the base 46
radially of the first portion 26. The second portion 28
has walls defining a central opening 48 that will slide
30 axially along the bolt 14, and has sockets adapte~ to
receive the projecting parts 44 of the first portion 26
when the portions 26 and 28 are in their lock position so
that t.he end wall 38 will close the distal ends o the
brush 16 receiving channels in the projecting parts 44,
35 and the portions 26 and 28 will be key~-d together to
prevent relative rotation of the portions 26 and 28. ~ach
portion 26 or 28 also has a slot or window 52 through its
3~366
end wall 36 or 38 opening into each oE the passageways 30
to aEEord a visual inspection to determine whether a
si~nificant amount of one of the lengths 1~ of abrasive-
coated material remains in the passageway 30.
The brushes 16 can include bristles of natural
or polymeric materials, and are preferakly formed of nylon
bristles of a fairly large diameter ~e,g., 0.015 inch or
0.038 CM. ) which have been found to provide a more
effective and long-wearing support for the projecting
por-tions of the lengths 18 of abrasive-coated material
than natural bristles. Each brush 16 is formed in a
conventional manner by bending lengths oE the bristles 180
degrees around a rod (not shown) and clamping a generally
U-shaped clasp over the portions of the bristles extending
around the rod to form the base 46 for the brush 16.
The lengths 18 of abrasive-coated material are
longitudinally scored (see Figure 5) in a known manner so
that their projecting portions supported on the brushes 16
can separate into longitudinal radially extending strips to
help conform to an irregular surface. The scalloped edges
24 on the lengths 18 of abrasive-coated material not only
afford engagement by the lugs 32 to retain the lengths 18
of abrasive-coated material in place, but also res-trict
edge cutting oE a workpiece by the abrasive-coated
material, which is a known advantage of scalloped-edged
abrasive as is described in U.S. Patent No. 2,637,956.
High-grade abrasive-coated material oE any grit may be used
in the wheel 10 with preferred abrasive materials belng
those sold under the trade designation Three-M-ite or
Tri-M-ite by Minnesota Mining and ManuEacturing Company oE
St. Paul, Minnesota. Grits of 60 and coarser have been
found to be particularly advantageous when used on metal
surfaces as they have a tendency to peen as well as abrade
the surface and provide surprisingly hiyh removal rates.
To use the sanding wheel 10 a user simply
engages the distal end of the bolt 14 with the chuck oE a
drive motor such as an electric drill, activates the drive
~.3 93t~
motor, and applies the projecting portions of the lengths
18 of abrasi-~e-coated material supported against the
brushes 16 to a workpiece. When one or more of the
lengths 18 of abrasive-coated material need to be extended
due to wear or need to be changed to provide another s.ize
grit, the user loosens the knurled nut 34 which allows the
portions 26 and 28 of the hub assembly 12 to separa-te to
their ~eleased position by movement o.E the second portion
28 along the bolt 14 (which movement is aided by the
influence of a coil spring 54 around the bolt 14 between
the portions 26 and 28), whereupon the lugs 32 separa-te
from the scalloped edges 24 of the lengths 18 of abrasive-
coated material and allow them to be moved freely along
the passageways 30 and through the slots 20 to reposition
or change them as desired. The nut 34 i5 then again tight~
ened to move the portions 26 and 28 to their lock position
with the lugs between the scallops along the edges 24, and
the sanding wheel 10 is ready for further use.
Figure 6 illustrates a second alternate embodi-
ment of a sanding wheel according to the present inventiongenerally designated by the reference numeral 60.
Like the sanding wheel 10, the sanding wheel 60
comprises a cylindrical hub assembly 62 from which axially
projects a shaft 64 having a distal portion adapted to be
engaged and rotated by a drive motor (not shown) to rotate
the sanding wheel 60 in a first direction indicated by an
arrow in Figure 60 A plurality of flexible support members
or brushes 66, identical to the brushes 16, each have one
end fixed on the hub assembly 62 by means similar to those
used in the sanding wheel 10 and project generally radially
outwardly of a cylindrical peripheral wall or periphery 67
oE the hub assembly 62. A plurality of individual
nonconnected lengths 68 o~ flexible abrasive-coated
material each extend through a diE:Eerent slot 70 in the
periphery 67 oE the hub assembly 62, ald are positioned so
that their outer projecting end portions project along the
surfaces oE adjacent ones of the brushes 66 that lead when
.6
the wheel 60 is rotated in the first direction so that the
projec-ting end portions of the lengths 68 of abrasive-w
coated material can be yieldably pressed into abrasive
engagement with a flat or irregular surface. The hub
assembly 62 also comprises first and second portions which
define a separate helical passageway 80 for each of the
lengths 68 oE abrasive-coated material, with each of the
hub portions defining a different edge of each of the
passageways 80.
Unlike the sanding wheel 10, however, the
portions oE the hub assembly 62 can be more permanently
Eixed together as by screws (not shown) and the means ~or
releasably securing the lengths 68 of abrasive-coated
material in the hub assembly 62 comprises a plurality of
self-locking cams 82. Each cam 82 is mounted on a shaft
83 supported between the portions of the hub asse~bly 62
adjacent its periphery 67 for free rotation about an axis
parallel to the axis of the hub assembly 62 between (1.3 a
lock position with the periphery of the cam 82 pressing
the lengths 68 of abrasive-coated material into engagement
with a wall of the hub assembly 62 defining the passageway
80 for the length 68 of abrasive-coated material, and
(2) a released position with the periphery of the cam 82
spaced from the length 68 of abrasive-coated material
25 along that wall to permit movement of the length 68 of
abrasive-coated material into or out of the passageway 80.
Each cam 82 is shaped and oriented so that friction between
the length 68 of abrasive-coated material and the cam 82
when the length 68 is pulled from the hub assembly 62
through the passageway 80 will rotate the cam 82 toward its
lock position. Thus centrifugal force or engagement with a
workpiece will not throw or pull the lengths 68 of
abrasive~coated material from the hub assembly 62. The
cams 82 can be rotated to ~heir released positions by
35 pushing the lengths 68 of abrasive-coa~ed material into the
pass~geways 80, however, and the cams 82 can then be
manually held in their released posi-tions so that the
93~366
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len~ths 68 of abrasive-coated material can be freely pulled
out of the passageways 80.
Figure 7 illustrates a third alternate embodi-
ment of a sanding wheel according to the present invention
generally designated by the reference numeral 90.
Like the sanding wheels 10 and 60, the sanding
wheel 90 comprises a cylindrical hub assembly 92 which
defines a separate helical passageway 94 for each oE a
plurality of lengths g6 of abrasive-coated material, from
which hub assembly 92 axially projects a shaft (not shown)
having a distal portion adapted to be engaged and rotated
by a drive motor (not shown) to rotate the sanding wheel
90 in a first direction indicated by an arrow in Figure 7.
A plurality of flexible support members or brushes 98
identical to the brushes 16 each have one end supported on
the hub assembly 92 and projecting generally radially
outwardly of a cylindrical periphery 100 of the hub
assembly 92. The lengths 96 of Elexible abrasive-coa-te-l
material each extend through a different slot 102 through
the peripheral wall or periphery 100 of the hub assembly
92, and are positioned so that their outer projecting end
portions project along the surfaces o~ adjacent ones o the
brushes 98 that lead when the wheel 90 is rotated in the
first direction so that the outer end portions of the
lengths 96 of abrasive-coated material can be yieldably
pressed into abrasive engagement with a Elat or irregular
surface.
Unlike the sanding wheels 10 and 60, however,
the means for releasably securing the lengths 96 oE
abrasive~coated material in the hub assembly 92 comprises
a plurality of lock members 104 on which the brushes 98
are mounted. The lock members 104 are mounted on the hub
assembly 92 adjacent its periphery 100 Eor individual
pivotal motion about an axis parallel to the a~is of the
hub assembly 92, between lock position, with lips 106 on
the loc]c members 104 pressing the lengths 96 of abrasive-
coated material into engagement with walls o the hub
assembly 92 defining the passageways 94 for the lengths 96
of abrasive-coated material, and released positions with
the lips 106 of the lock members 104 spaced from the
lengths 96 of abrasive-coated material along the passage-
ways 94 to permit individual movement of the length 96 ofabrasive-coated material into or out of the passageways
9~. Leaf springs 108 are positioned between the lock
members 104 and the hub assembly 92 -to provide means for
biasing the lock members 104 to their lock positions. The
locJc members 104 can be individually manually pivoted to
their released positions by pushing directly on the lock
members 104 or on the brushes 98, however, and the len~-ths
96 of abrasive-coated material can then be moved into or
out of the passageways 94. Th~ lock members 104 are
positioned so that the force applied to the brushes 98
when they are pressin~ the len~ths 96 of abrasive-coated
material against a workpiece will tend to also bias the
loc]c members 10~ to their lock positions.
The present invention has now been described
with reference to three embodiments thereof. It will be
apparent to those skilled in the art that many changes can
be made in the structure of the embodiments described
without departing from the spirit of the present
invention. For example, the wheel may be adapted for
attachment to an arbor attached to the rotor of a drive
motor, or an arbor rotatably mounted on fixed supports as
are commonly found in work shops; or the support members
may be provided by flexible structures other than brushes.
Thus, the scope of the present invention should not be
30 limited to the structures described in this specification,
but only by the structures ~ecited in the dependent c~aims
and their equivalents.
