BULK MATERIAL CONVEYOR BELT SCRAPER HAVING A DUST SKIRT AND
METHOD OF USING THE SAME
Cross-Reference to Related Applications
[0001 ] This application claims the benefit of priority to U.S. Application No.
13/053,782 filed on March 22, 201 1 which is incorporated by reference herein in its'
entirety.
Statement Regarding Federally Sponsored Research or Development
[0002] Not Applicable.
Appendix
[0003] Not Applicable.
BACKGROUND OF THE INVENTION
Field of the Invention
[0004] This invention pertains generally to bulk material conveyor belt assemblies.
More specifically, this invention pertains to a conveyor belt scraper comprising a skirt
that prevents bulk material that is removed from the conveyor belt by the belt scraper
from migrating to mating surfaces between the belt scraper and the mounting
member that holds the scraper blade. By preventing bulk material removed from the
conveyor belt from migrating to the mating surfaces between the belt scraper and the
mounting member, such material does not interfere with the replacement of worn belt
scrapers. The belt scraper assembly also utilizes securing pegs that have an
elongate transverse cross-section that distribute bearing loads more evenly than
would securing pegs having circular transverse cross-sections.
General Background
[0005] Bulk material conveyor belt systems often comprise belt scraper assemblies
that are configured to remove bulk material carryback from the belt. Due to the
function they serve, belt scrapers necessarily become covered with dust and fine
particles removed from the conveyor belt. This is especially the case on the leading
side of a belt scraper, since the leading side is the side that engages and redirects
the bulk material removed from the conveyor belt. Unfortunately, the dust and fine
particles can make the task of replacing worn belt scrapers difficult since the dust
and fine particles often interfere with mating surfaces between the belt scrapers and
the mounts that hold the belt scrapers. For example, belt scrapers are often formed
of polymeric material, which can make it difficult to rigidly attach such belt scrapers
to belt scraper mounts. As such, in some cases, the belt scraper comprises a
tapered mounting portion that mates with, and is inserted into, a correspondingly
tapered rigid pocket of the mount that supports the belt scraper. This provides the
belt scraper with good fixation relative to the mount. However, during use, dust from
the bulk material scraped from the conveyor belt can work its way into the pocket of
the mount. While this doesn't necessarily interfere with the operation of the belt
scraper, it does make it difficult to replace the belt scraper when worn and, more
particularly, to attach a replacement belt scraper to the mount.
SUMMARY OF THE INVENTION
[0006] The present invention helps prevent bulk material dust removed from the
conveyor belt from interfering with the process of replacing worn belt scrapers. The
invention is achieved by providing a belt scraper with a skirt that shields mounting
surfaces from the bulk material dust. The invention also pertains to an improved
securing mechanism for attaching belt scrapers to belt scraper mounts. The
improved securing mechanism more evenly distributes bearing loads between the
belt scrapers and their respective mounts. This eliminates local yielding that can
cause belt scrapers to become loose over time.
[0007] In a first aspect of the invention, a bulk material conveyor belt scraper has a
leading side and a trailing side and comprising a scraper portion, a mounting portion,
and a skirt portion. The scraper portion has a scraping edge that lies on the leading
side of the belt scraper. The scraping edge is configured and adapted to engage a
moving conveyor belt in a manner such that the scraper portion removes bulk
material from the conveyor belt, with the leading side of the belt scraper leading the
trailing side relative to the movement of the belt. The mounting portion of the belt
scraper is integrally formed with the scraper portion as a monolithic part. The
mounting portion is opposite the scraper portion and protrudes therefrom in a
manner such that the mounting portion tapers in a narrowing manner as it extends
away from the scraper portion. The skirt portion is integrally formed with the scraper
portion and the mounting portion as a portion of the monolithic part, and forms a
portion of the leading side of the belt scraper. The skirt portion protrudes from the
scraper portion and is adjacent to and spaced from the mounting portion in a manner
such that the skirt portion lies between the mounting portion and the leading side of
the belt scraper and such that a slot extends through the belt scraper parallel to the
scraping edge.
[0008] In another aspect of the invention, a method comprises operating a bulk
material conveyor belt system. The conveyor belt system comprises a belt moving in
an endless loop. The method includes engaging the belt with a belt scraper
assembly in a manner removing material from the conveyor belt. The belt scraper
assembly comprises a belt scraper and a mounting member. The belt scraper has a
leading side and a trailing side. The belt scraper is in contact with the belt in a
manner such that there is relative movement therebetween with the leading side of
the belt scraper leading the trailing side. The belt scraper also comprises a scraper
portion, a mounting portion, and a skirt portion. The scraper portion is engaged with
the belt. The mounting portion is integrally formed with the scraper portion as a
monolithic part and protrudes from the scraper portion. The skirt portion is integrally
formed with the scraper portion and the mounting portion as a portion of the
monolithic part and forms a portion of the leading side of the belt scraper. The skirt
portion protrudes from the scraper portion and is adjacent to and spaced from the
mounting portion in a manner such that the skirt portion lies between the mounting
portion and the leading side of the belt scraper. The mounting member comprises a
pocket. The mounting portion of the belt scraper is positioned in the pocket of the
mounting member. The skirt portion is outside of and adjacent the pocket, and
shields the pocket in a manner preventing at least some the material from entering
the pocket.
[0009] Further features and advantages of the present invention, as well as the
operation of the invention, are described in detail below with reference to the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Figure 1 depicts an exploded perspective view of a belt scraper assembly in
accordance with the invention.
[0011] Figure 2 depicts another exploded perspective view of the belt scraper
assembly shown in Figure 1.
[001 2] Figure 3 is a perspective view of the belt scraper assembly shown in Figures
1 and 2 and is shown with the components assembled to each other.
[001 3] Figure 4 is another perspective view of the belt scraper assembly from a
different point of view.
[0014] Figure 5 is a side view of the belt scraper by itself.
[0015] Figure 6 is an elevation view of the leading side of the belt scraper.
[0016] Figure 7 is an elevation view of the trailing side of the belt scraper.
[0017] Figure 8 is a perspective view of the belt scraper.
[001 8] Reference numerals in the written specification and in the drawing figures
indicate corresponding items.
DETAILED DESCRIPTION
[001 9]A belt scraper assembly 10 in accordance with the invention is shown in
Figures 1-4. The belt scraper assembly 10 comprises a belt scraper 12, a mounting
member 14, and two securing pegs 16.
[0020] The belt scraper 12 itself has a leading side 18 and a trailing side 20 and is
preferably symmetric about a plane. The leading side 18 of the belt scraper 12 is
preferably convex. The trailing side 20 is preferably concave. The belt scraper 12
comprises a scraper portion 22, a mounting portion 24 and a skirt portion 26. The
scraper portion 22, the mounting portion 24, and the skirt portion 26 are preferably
formed as a monolithic integral part of polymeric material. The scraper portion 22
comprises a scraping edge 28 on the leading side 18 of the belt scraper 12 that is
configured and adapted to engage a moving conveyor belt.
[0021 ] The mounting portion 24 of the belt scraper 12 protrudes from the scraper
portion 22 and tapers in a narrowing manner as it extends away from the scraper
portion. This tapering aspect of the mounting portion 24 is most notable in Figure 5
and is shown as the angle a (a being greater than zero) between the front face 30
and the rear face 32 of the mounting portion. The mounting portion 24 comprises a
primary slot 34 that is parallel to and centered about the plane of symmetry of the
belt scraper 12. The primary slot 34 divides and separates the mounting portion 24
into two mounting protrusions 36 that are mirror images of each other. Each of the
mounting protrusions 36 comprises a relief slot 38 and a peg opening 40. Each of
the peg openings 40 has an elongate transverse cross-section (i.e. the cross-section
perpendicular to its longitudinal direction) oriented with its larger dimension
perpendicular to the plane of symmetry of the belt scraper 12. The peg openings 40
extend completely through the mounting portion 24 of the belt scraper 12. Each
relief slot 38 bisects its respective mounting protrusion 36 and intersects the
respective peg opening 40. The relief slots 38 are parallel to the plane of symmetry
of the belt scraper 12. The mounting portion 24 of the belt scraper 12 further
comprises guide notches 42 that serve as visual and tactile guides when the belt
scraper is being inserted into the mounting member 14 of the belt scraper assembly
10 (discussed below).
[0022]The skirt portion 26 of the belt scraper 12 forms a portion of the leading side
18 of the belt scraper and extends from the scraper portion 22. The skirt portion 26
is adjacent to and spaced from the mounting portion 24 in a manner such that a slot
44 is formed between the skirt portion and the mounting portion. The peg openings
40 that extend through the mounting portion 24 also extend through the skirt portion
26 of the belt scraper 12.
[0023] The mounting member 14 is configured and adapted to receive the mounting
portion 24 of the belt scraper 12. The mounting member 14 is preferably formed of
metal and comprises two pockets 46, with each being adapted to receive one of the
mounting protrusions 36 of the mounting portion 24 of the belt scraper 12. Similar to
the mounting portion 24 of the belt scraper 12, each pocket 46 of the mounting
member 14 tapers in a narrowing manner as it extends into the mounting member.
The longitudinal walls 48 of the mounting member 14 comprise two peg openings 50,
with each extending into a respective one of the pockets 46. The lateral walls 52 of
the mounting member 14 comprise guide protrusions 54 that protrude slightly into
the pockets 46.
[0024]The securing pegs 16 each comprise a tapered lead-in section 56 and a main
body portion 58. The main body portion 58 of each securing peg 16 preferably has
an elongate transverse cross-section that is slightly larger than the transverse
cross-section of the peg openings 40 of the belt scraper 12. The main body portion
58 of each securing peg 16 also preferably has length sufficient to extend through
both of the longitudinal walls 48 of the mounting member 14.
[0025] The belt scraper assembly 10 is assembled by inserting the mounting
protrusions 36 of the belt scraper 12 into the pockets 46 of the mounting member 14.
The tapered nature of the mounting protrusions 36 and of the pockets 46 ensures
that the two parts rigidly engage each other when they are assembled to each other.
As the mounting protrusions 36 are being inserted into the pockets 46 of the
mounting member 14, the guide protrusions 54 on the lateral walls 52 of the
mounting member push inward on the mounting protrusions 36. The relief slots 38
of the mounting portion 24 of the belt scraper 12 allow the mounting protrusions 36
to resiliently deform as this occurs. Once the mounting protrusions 36 of the belt
scraper 2 are fully seated in the pockets 46 of the mounting member 14, the guide
notches 42 of the belt scraper become aligned with the guide protrusions 54 of the
mounting member. This provides tactile confirmation that the parts are fully engaged
with each other. To prevent the belt scraper 12 from being dislodged from the
mounting member 14, the securing pegs 16 are inserted through the peg openings
40 of the belt scraper and through the peg openings 50 of the mounting member.
The lead-in portions 56 of the securing pegs 16 facilitate initial alignment of the pegs
with the openings. The securing pegs 16 have a slight interference fit in the peg
openings 40 of the belt scraper 12 and therefore must be forcibly driven into or out of
the belt scrapers 12. This prevents the securing pegs 16 from inadvertently
separating from the belt scraper assembly 10. As assembled, the skirt portion 26 of
the belt scraper 12 covers the exterior of one of the longitudinal walls 48 of the
mounting member 14, and that longitudinal wall extends into the slot 44 that is
formed between the skirt portion and the mounting portion 24 of the belt scraper.
[0026] Once assembled as described above, the belt scraper assembly 10 can be
brought into contact with a moving conveyor belt for the purpose of removing bulk
material from the conveyor belt. As this is done, the scraping edge 28 of the scraper
portion 22 of the belt scraper 12 engages the conveyor belt and bulk material is
forced onto the leading side 18 of the belt scraper 12. It should be appreciated that
the skirt portion 26 of the belt scraper 12 protects and shields the pockets 46 of the
mounting member 14. As such, bulk material is not able to migrate from the leading
side 18 of the belt scraper 12 into the pockets 46 of the mounting member 14. This
prevents the bulk material from interfering with the replacement of the belt scraper
12 after its useful life is exhausted. It should also be appreciated that the elongate
transverse cross-sections of the securing pegs 16 and peg openings 40, 50, is
configured to distribute pull-out bearing loads evenly across the width of the pegs
and openings. This is an improvement over the use of securing pegs and peg
openings having circular transverse cross-sections, which tend to focus bearing
loads over small portions of the bearing surfaces. Thus, the elongated transverse
cross-sections of the securing pegs 16 and peg openings 40, 50 helps prevent the
peg openings 40 of the belt scraper 12 from yielding during the useful life of the belt
scraper.
[0027] In view of the foregoing, it should be appreciated that the invention achieves
the several advantages over prior art conveyor belt scrapers and belt scraper
assemblies.
[0028]As various modifications could be made in the constructions and methods
herein described and illustrated without departing from the scope of the invention, it
is intended that all matter contained in the foregoing description or shown in the
accompanying drawings shall be interpreted as illustrative rather than limiting. Thus,
the breadth and scope of the present invention should not be limited by any of the
above-described exemplary embodiments, but should be defined only in accordance
with the following claims appended hereto and their equivalents.
[0029] It should also be understood that when introducing elements of the present
invention in the claims or in the above description of exemplary embodiments of the
invention, the terms "comprising," "including," and "having" are intended to be openended
and mean that there may be additional elements other than the listed
elements. Additionally, the term "portion" should be construed as meaning some or
all of the item or element that it qualifies. Moreover, use of identifiers such as first,
second, and third should not be construed in a manner imposing any relative position
or time sequence between limitations. Still further, the order in which the steps of
any method claim that follows are presented should not be construed in a manner
limiting the order in which such steps must be performed unless such order is
necessary.

What is claimed is :
1. A bulk material conveyor belt scraper having a leading side and a trailing side,
the belt scraper comprising:
a scraper portion, the scraper portion having a scraping edge that lies on the
leading side of the belt scraper, the scraping edge being configured and adapted to
engage a moving conveyor belt in a manner such that the scraper portion removes
bulk material from the conveyor belt with the leading side of the belt scraper leading
the trailing side;
a mounting portion, the mounting portion being integrally formed with the
scraper portion as a monolithic part, the mounting portion protruding from the
scraper portion opposite the scraping edge, the mounting portion tapering in a
narrowing manner as it extends away from the scraper portion;
a skirt portion, the skirt portion being integrally formed with the scraper portion
and the mounting portion as a portion of the monolithic part and forming a portion of
the leading side of the belt scraper, the skirt portion protruding from the scraper
portion and being adjacent to and spaced from the mounting portion in a manner
such that the skirt portion lies between the mounting portion and the leading side of
the belt scraper and such that a slot extends through the belt scraper parallel to the
scraping edge.
2 . A belt scraper in accordance with claim 1 wherein two through-holes extend
through the mounting portion and the skirt portion.
3. A belt scraper in accordance with claim 2 wherein each of the through-holes
has an elongate transverse cross-section.
4. A belt scraper in accordance with claim 3 wherein the belt scraper is
symmetric about a plane of symmetry, and the transverse cross-section of each of
the through-holes has a longest dimension that is oriented perpendicular to the plane
of symmetry.
5. A belt scraper in accordance with claim 4 wherein the mounting portion of the
belt scraper consists of two protrusions that extend from the scraper portion, the two
protrusions are spaced from each other and lie on opposite sides of the plane of
symmetry, and one of the through-holes extends through one of the protrusions and
the other of the through-holes extends through the other of the through-holes.
6. A belt scraper in accordance with claim 1 wherein the leading side of the belt
scraper is convex.
7 . A belt scraper assembly comprising:
a belt scraper in accordance with claim 1; and
a mounting member, the mounting member being adapted and configured to
connect the belt scraper to a conveyor belt system, the mounting member
comprising a tapered pocket surrounded by four wall portions, the mounting portion
of the belt scraper being positioned in the tapered pocket of the mounting member
with one of the walls of the mounting member lying between the mounting portion of
the belt scraper and the skirt portion of the belt scraper.
8. A belt scraper assembly in accordance with claim 7 wherein two
through-holes extend through the mounting portion and the skirt portion of the belt
scraper and through two of the walls of the mounting member, and the assembly
further comprises two securing pegs that fill the through-holes in a manner
preventing the mounting portion of the belt scraper from being removed from the
pocket of the mounting member.
9. A belt scraper assembly in accordance with claim 8 wherein the belt scraper
is symmetric about a plane of symmetry and each of the through-holes has an
elongate transverse cross-section, and the transverse cross-section of each of the
through holes has a longest dimension that is oriented perpendicular to the plane of
symmetry.
10. A method comprising:
operating a bulk material conveyor belt system, the conveyor belt system
comprising a belt moving in an endless loop;
engaging the belt with a belt scraper assembly in a manner removing material
from the conveyor belt, the belt scraper assembly comprising a belt scraper and a
mounting member, the belt scraper having a leading side and a trailing side, the belt
scraper being in contact with the belt in a manner such that there is relative
movement therebetween with the leading side of the belt scraper leading the trailing
side, the belt scraper comprising a scraper portion, a mounting portion, and a skirt
portion, the scraper portion being engaged with the belt, the mounting portion being
integrally formed with the scraper portion as a monolithic part, the mounting portion
protruding from the scraper portion, the skirt portion being integrally formed with the
scraper portion and the mounting portion as a portion of the monolithic part and
forming a portion of the leading side of the belt scraper, the skirt portion protruding
from the scraper portion and being adjacent to and spaced from the mounting portion
in a manner such that the skirt portion lies between the mounting portion and the
leading side of the belt scraper, the mounting member comprising a pocket, the
mounting portion of the belt scraper being positioned in the pocket of the mounting
member, the skirt portion being outside of and adjacent the pocket, the skirt portion
shielding the pocket in a manner preventing at least some the material from entering
the pocket.
1 . A method in accordance with claim 10 wherein two through-holes extend
through the mounting portion and the mounting member, and further comprising
securing the belt scraper to the mounting member by press fitting a securing pin in
each of the through-holes.
12. A method in accordance with claim 11 wherein each of the through-holes also
extends through the skirt portion of the belt scraper.
13. A method in accordance with claim 11 wherein each of the through-holes has
an elongate transverse cross-section and the belt scraper is symmetric about a
plane of symmetry, and the transverse cross-section of each of the through-holes
has a largest dimension that is oriented perpendicular to the plane of symmetry.