U.S. patent application number 14/699361 was filed with the patent office on 2015-09-10 for wear indicator.
The applicant listed for this patent is AKEBONO BRAKE INDUSTRY CO., LTD.. Invention is credited to Brian Lewis Boyle.
Application Number | 20150252862 14/699361 |
Document ID | / |
Family ID | 50929655 |
Filed Date | 2015-09-10 |
United States Patent
Application |
20150252862 |
Kind Code |
A1 |
Boyle; Brian Lewis |
September 10, 2015 |
WEAR INDICATOR
Abstract
A wear indicator comprising: (a) a connector that attaches the
wear indicator to a brake pad, the brake pad including a friction
material having a plane: (b) a scraper: and (c) an indicator
portion: wherein the indicator portion forms a cantilever
connection with the scraper and extends parallel to the plane of
the friction portion.
Inventors: |
Boyle; Brian Lewis;
(Farmington Hills, MI) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
AKEBONO BRAKE INDUSTRY CO., LTD. |
Tokyo |
|
JP |
|
|
Family ID: |
50929655 |
Appl. No.: |
14/699361 |
Filed: |
April 29, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13713067 |
Dec 13, 2012 |
9038784 |
|
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14699361 |
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Current U.S.
Class: |
188/1.11W |
Current CPC
Class: |
F16D 66/02 20130101;
F16D 55/225 20130101; B60T 17/22 20130101 |
International
Class: |
F16D 66/02 20060101
F16D066/02; F16D 55/225 20060101 F16D055/225 |
Claims
1. A wear indicator comprising: a. a connector that attaches the
wear indicator to a brake pad, the connector including a connection
body and a connection plate on each side of the connection body
that attaches the wear indicator to the brake pad, and the brake
pad including a friction material haying a plane; b. a scraper
configured to contact a rotor in a brake system; and c. an
indicator portion; wherein the indicator portion forms a cantilever
connection with the scraper and extends parallel to the plane of
the friction material.
2-20. (canceled)
21. The wear indicator of claim 1, wherein the indicator portion
includes an indicator body attached to and extending from the
scraper and the indicator body extends from the scraper in a
direction of rotation of the rotor.
22. The wear indicator of claim 1, wherein the indicator portion
includes an indicator body and one or more indicator ends extending
from the indicator body, wherein the one or more indicator ends
form a cantilever connection with the indicator body so that the
one or more indicator ends extend over the brake pad without
contacting the brake pad.
23. The wear indicator of claim 22, wherein the indicator portion
includes at least two indicator ends extending from the indicator
body substantially in a same plane.
24. The wear indicator of claim 1, wherein the indicator portion
includes an indicator body and the indicator body has a narrow neck
region.
25. The wear indicator of claim 24, wherein the indicator body
having a narrow neck region is generally hour glass shaped.
26. The wear indicator of claim 1, wherein the wear indicator has a
shape that substantially follows one or more contours of the brake
pad.
27. The wear indicator of claim 1, wherein the scraper includes a
scraper body and a scraper indicator, and wherein the scraper
indicator forms a cantilever connection with the scraper body and
the scraper extends over the friction material.
28. The wear indicator of claim 27, wherein a gap is formed between
at least a portion of the friction material and the scraper.
29. The wear indicator of claim 1, wherein the indicator portion
and the scraper form an angle of about 145 degrees or less.
30. A wear indicator comprising: a. a connector that attaches the
wear indicator to a pressure plate of a brake member; b. a scraper
configured to contact a rotor in a brake system that extends from
the pressure plate of the brake member over a friction material so
that when a predetermined amount of the friction material is
removed, the scraper assists in creating an indication; and c. an
indicator portion that works in conjunction with the scraper to
create the indication, wherein the indicator portion has a fixed
end that is connected to the scraper and at least one free end that
extends over the pressure plate of the brake member so that the
indicator portion is free to move to create the indication.
31. The wear indicator of claim 30, wherein the connector includes
one or more connection plates for attaching the wear indicator to
the pressure plate.
32. The wear indicator of claim 31, wherein the one or more
connection plates and the pressure plate are connected via a peened
connection.
33. The wear indicator of claim 30, wherein the indicator portion
has at east two free ends that are substantially discrete from each
other.
34. The wear indicator of claim 33, wherein the at least two free
ends extend substantially in a same plane.
35. The wear indicator of claim 30, wherein the scraper includes a
scraper body and a scraper indicator, and the scraper indicator
extends over the friction material.
36. The wear indicator of claim 30, wherein the indicator portion
and the scraper form an angle of about 145 degrees or less.
37. The wear indicator of claim 30, wherein the indicator portion
is at least 5 mm in length.
38. The wear indicator of claim 30, wherein the indicator portion
is free of contact with the pressure plate, the friction material,
or both.
39. The wear indicator of claim 30, wherein the indication is an
audible noise.
Description
FIELD
[0001] The present teachings generally relate to a device that
connects to a brake pad and produces an audible sound during a
brake apply when a friction material of the brake pad becomes thin
and/or a brake pad may need to be replaced.
BACKGROUND
[0002] The present teachings are predicated upon providing an
improved disc brake system for use with vehicles. For example, the
disc brake system may be used with almost any vehicle (e.g. car,
truck, bus, train, airplane, or the like). Alternatively, the disc
brake system may be integrated into assemblies used for
manufacturing or other equipment that require a brake such as a
lathe, winder for paper products or cloth, amusement park rides, or
the like. However, the present teachings are most suitable for use
with a passenger vehicle (i.e. a car, truck, sports utility
vehicle, or the like).
[0003] Generally, a braking system includes a rotor, a caliper
body, a support bracket, an inboard brake pad, and an outboard
brake pad that are on opposing sides of the rotor. The caliper body
further includes one or more fingers, a piston bore, and a bridge
that connects the one or more fingers to the piston bore. The
piston bore houses a piston. The piston bore has a bore axis that
the piston moves along during a brake apply and a brake retract.
The piston bore may include a fluid inlet, a closed wall, a front
opening, and a cylindrical side wall that includes a seal groove
located near the front opening. Typically, the fluid inlet is
located in the closed wall of the piston bore so that when pressure
is applied the fluid will flow into the piston bore. During a
pressure apply the fluid will push the piston towards the front
opening and into contact with a brake pad. Generally, brake pads
include a pressure plate and friction material. During each
pressure apply the friction material contacts a rotor, which
removes a small portion of the friction material. Over repeated
pressure applies the friction material slowly reduces, and due to
the location of the brake pads it may be difficult for a user to
check the thickness of the friction material, users may not check
brake pad thickness, or a user may forget to check brake pad
thickness. If the friction material is reduced beyond a certain
point, braking performance may begin to reduce. What is needed is a
wear indicator that monitors the thickness of the friction material
and when the friction material thickness reaches a predetermined
thickness, the wear indicator makes an audible noise so that the
user is alerted to check the thickness of the friction material
before braking performance is impacted.
[0004] Examples of clip on wear indicators are disclosed in U.S.
Pat. Nos. 3,611,283; 4,037,689; 4,124,105; 4,241,327; 4,460,067;
4,498,559; 4,742,326; 5,385,670; 6,311,554 all of which are
expressly incorporated herein by reference for all purposes.
Examples of electronic wear indicators are disclosed in U.S. Pat.
Nos. 3,297,985; 3,882,448; and 6,302,241 all of which are
incorporated herein by reference for all purposes.
[0005] What is needed is a wear indicator that attaches to the
pressure plate of a brake pad and is fastened to the pressure plate
in a manner so that the wear indicator is not damaged and/or
inadvertently removed during installation of one or more parts onto
the brake pad and/or the brake pad being installed into the brake
system. What is needed is a wear indicator that produces an audible
sound so that a user is adequately alerted when a frictional
material thickness reaches a predetermined thickness.
SUMMARY
[0006] One possible embodiment of the present teachings include: A
wear indicator comprising: (a) a connector that attaches the wear
indicator to a brake pad, the brake pad including a friction
portion having a plane; (b) a scraper; and (c) an indicator
portion; wherein the indicator portion forms a cantilever
connection with the scraper and extends parallel to the plane of
the friction portion.
[0007] One possible embodiment of the present teachings include: a
wear indicator comprising: (a) a connector that attaches the wear
indicator to a pressure plate of a brake member; (b) a scraper that
extends from the pressure plate of the brake member over a friction
material so that when a predetermined amount of the friction
material is removed the scraper assists in creating an indication;
and (c) an indicator portion that works in conjunction with the
scraper to create the indication; wherein the indicator portion is
generally planar and is free of any bends having an angle of 45
degrees or more.
[0008] Another possible embodiment of the present teachings
include: a brake system comprising: (a) one or more brake members
comprising: (i) a pressure plate and (ii) a friction material; (b)
one or more wear indicators comprising: (i) a connector for
attaching the one or more wear indicators to the pressure plate of
the one or more brake members; (ii) a scraper that extends over the
friction material so that when a sufficient amount of friction
material is removed the scraper extends beyond the friction
material creating a sound; and (iii) an indicator portion that
extends along the pressure plate.
[0009] The present teachings provide a wear indicator that attaches
to the pressure plate of a brake pad and is fastened to the
pressure plate in a manner so that the wear indicator is not
damaged and/or inadvertently removed during installation of one or
more parts onto the brake pad and/or the brake pad being installed
into the brake system. The present teachings provide a wear
indicator that produces an audible sound so that a user is
adequately alerted when frictional material thickness reaches a
predetermined thickness.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 illustrates a perspective view of a wear
indicator;
[0011] FIG. 2 illustrates a side view of the wear indicator of FIG.
1;
[0012] FIG. 3A illustrates an example of a wear indicator connected
to a pressure plate;
[0013] FIG. 3B illustrates a side view of a wear indicator
connected to a brake pad;
[0014] FIGS. 4A and 4B illustrate an example of a wear indicator
that has been peened onto the brake pad;
[0015] FIG. 5 illustrates an example of a wear indicator with
extended indicator ends;
[0016] FIGS. 6A and 6B illustrate a front and rear view of a brake
pad including the wear indicator;
[0017] FIG. 7 illustrates brake system including a brake pads
having the wear indicator; and
[0018] FIG. 6 illustrates a vehicle during a brake apply.
DETAILED DESCRIPTION
[0019] The explanations and illustrations presented herein are
intended to acquaint others skilled in the art with the invention,
its principles, and its practical application. Those skilled in the
art may adapt and apply the invention in its numerous forms, as may
be best suited to the requirements of a particular use.
Accordingly, the specific embodiments of the present invention as
set forth are not intended as being exhaustive or limiting of the
teachings. The scope of the teachings should, therefore, be
determined not with reference to the above description, but should
instead be determined with reference to the appended claims, along
with the full scope of equivalents to which such claims are
entitled. The disclosures of all articles and references, including
patent applications and publications, are incorporated by reference
for all purposes. Other combinations are also possible as will be
gleaned from the following claims, which are also hereby
incorporated by reference into this written description.
[0020] As discussed above a disc brake system generally includes a
support bracket, a caliper, a rotor, and at least two brake pads.
Each brake pad typically includes at least a pressure plate and
friction material. The pressure plate and the friction material lie
in a plane. The plane of the pressure plate and the plate of the
friction material are substantially parallel to each other. The one
or more pressure plates may be of any size and shape so that the
pressure plate assists in creating a brake apply. The pressure
plate may have a sufficient width so that the pressure plate
assists in creating a braking force. The width of the pressure
plate may be about 2 mm or more, about 3 mm or more, about 4 mm or
more, or about 5 mm or more. The width of the pressure plate may be
about 10 mm or less, about 8 mm or less, or about 7 mm or less. The
one or more pressure plates may include one or more features and/or
recesses so that one or more discrete components may be fixedly
attached to the one or more pressure plates via the one or more
features and/or one or more recesses. The one or more features
and/or one or more recesses may be sufficiently deep so that a
connector body when extended into the features and/or recesses is
sufficiently flush so that accidental contact with the connector
body is reduced and/or substantially eliminated. The brake pads may
include one or more shims. During a brake apply the friction
material may contact the rotor so that rotation of the rotor is
slowed and/or stopped. Repeated contact between the friction
material and the rotor results in a reduced thickness of the
friction material. The thickness of the friction material when new
may be about 4 mm or more, preferably about 5 mm or more, or more
preferably about 7 mm or more. The thickness of the friction
material, when new, may be about 15 mm or less, about 12 mm or
less, or about 10 mm or less. The friction material may be
considered a worn when the friction material is below about 3 mm,
about 2.5 mm or less, about 2.0 mm or less, or about 1.5 mm or
less. The friction material may directly connect to the pressure
plate. The friction material may connect to the pressure plate via
an under layer. The under layer may have a thickness of about 0.2
mm or more, about 0.5 mm or more, or about 1.0 mm or more. The
thickness of the underlayer may be be about 2 mm or less, about 1.5
mm or less, or about 1.2 mm or less. The thickness of the friction
material discussed herein includes the thickness of the underlayer.
A wear indicator may be used to actively monitor and/or passively
monitor the thickness of the friction material so that a user is
warned when the friction material becomes reduced to a
predetermined thickness.
[0021] The wear indicator may be any wear indicator that connects
to a pressure plate of a brake pad. The wear indicator may have any
configuration so that the wear indicator when contacting an
opposing part (e.g., a rotor) creates a noise. The wear indicator
may be attached to the pressure plate so that a largest dimension
extends along the direction of rotation of the rotor. For example,
the largest dimension of the wear indicator extends substantially
parallel to a face of the rotor. The wear indicator may be used in
conjunction with an electronic signal system. Preferably, the wear
indicator is free of an electronic signaling system. The wear
indicator may be made of any material that makes a noise when
rubbed against another material that is made of the same or a
different substance.
[0022] The material of the wear indicator may be any material that
may be shaped and formed. The material may be any material that may
exhibit some abrasive resistance, wear resistance, or both. The
wear indicator may be made of plastic, metal, a ceramic, a polymer,
a natural material, a synthetic material, or a combination thereof.
Preferably, the wear indicator is made of stainless steel. The
material may have a thickness. The thickness of the material may be
about 0.2 mm or more, about 0.3 mm or more, or about 0.5 mm or
more. The thickness of the material may be about 3 mm or less,
about 2 mm or less, or about 1 mm or less. The thickness of the
material may be any thickness so that the wear indicator may be
shaped to mirror the shape of a pressure plate, create a noise, or
both.
[0023] The wear indicator may have any configuration so that
substantially all of the wear indicator extends over a pressure
plate of a brake pad. The wear indicator may be free of or
substantially free of a portion that extends off of the pressure
plate on a side of the pressure plate opposite the friction
material. For example, a portion of the wear indicator may extend
over the pressure plate on a side of the pressure plate opposite
the friction material, but the wear indicator on the side proximate
to the friction material may step at the edge of the pressure
plate. A majority of the wear indicator may extend in a
longitudinal direction. The wear indicator may have a width and the
width may be less than the length of the wear indicator. The width
of the wear indicator may be about 2 mm or more, about 3 mm or
more, about 4 mm or more, or about 5 mm or more. The width of the
wear indicator may be about 10 mm or less, about 8 mm or less, or
about 7 mm or less. Preferably, the width of the wear indicator is
substantially equal to the width of the pressure plate as discussed
herein. The shape of the wear indicator may be substantially in a
longitudinal direction.
[0024] The wear indicator may have an overall length in the
longitudinal direction of about 10 mm or more, preferably about 15
mm or more, more preferably about 20 mm or more, or about 25 mm or
more. The wear indicator may have an overall length in the
longitudinal direction of about 50 mm or less, about 40 mm or less,
or about 30 mm or less. The wear indicator may be contoured. The
wear indicator may be contoured so that the wear indicator has a
complementary shape to a shape of the pressure plate. The shape of
the wear indicator may substantially mirror the shape of the
pressure plate. The shape of the wear indicator may curve and/or
bend so that the width of the wear indicator may be limited
substantially to the width of the pressure plate. The wear
indicator may include one or more bends so that the wear indicator
complements the shape of the pressure plate.
[0025] The bend may be any angle that assists the wear indicator in
mirroring the shape of the pressure plate. The bends may each be
about 15 degrees or more, about 25 degrees or more, or about 35
degrees or more. The bends may each be about 140 degrees or less,
about 125 degrees or less, about 105 degrees or less, or about 90
degrees or less. Preferably, the sum of all of the bends may be
about 205 degrees or less, preferably about 180 degrees or less,
more preferably about 160 degrees or less, or even more preferably
about 150 degrees or less. The sum of all of the bends may be about
30 degrees or more, about 45 degrees or more, or about 60 degrees
or more. The wear indicator may include a connector, an indicator,
and a scraper.
[0026] The connector may be any part of the wear indicator that
connects the wear indicator to a pressure plate of a brake pad. The
connector may be any shape and size so that the connector has
sufficient strength to connect the wear indicator to a pressure
plate; to hold the wear indicator on the pressure plate during a
brake apply, during installation, or both; to withstand a radial
force, a tangential force, or both relative to an axis of rotation
of a rotor; or a combination thereof. The connector may include one
or more connector plates and one or more connector bodies.
[0027] The one or more connector bodies may be any part of the
connector that is located proximate to a pressure plate, which is
centrally located so that one or more connector plates extend from
the connector body, are connected to an indicator, are connected to
a scraper, or a combination thereof. Preferably, the connector body
includes at least one connector plate that extends from the
connector body. The connector body may be of any size and shape so
that the connector body extends over a side and/or an edge of the
pressure plate so that a connector plate may be located on each
side of the pressure plate. Preferably the connection body is sized
so that the connection body fits within the feature and/or the
recess in the pressure plate so that the connection body when
connected is not substantially wider than the width of the pressure
plate. The connector body may have a size that is substantially
similar to the thickness of the feature and/or pressure plate. The
connector body may be wider than the feature and/or recess in the
pressure plate, wide than feature and/or recess in the pressure
plate, or a combination of both. The connector body preferably is
sufficiently wide so that the connector body extends from a forward
edge of a pressure plate to a rearward edge of a pressure plate.
More preferably, the connector body may extend from a first side of
the pressure plate to a second side of the pressure plate so that a
connector plate extends or connects along each side of the pressure
plate to the connector body. The one or more connector bodies may
be directly attached to the pressure plate. The one or more
connector bodies may be fastened directly to the pressure plate via
one or more fasteners. The one or more fasteners may be a screw, a
rivet, a pin, peened on via a button, protrusion stamped in the
pressure plate, or a combination thereof. The connector body may be
free of one or both connector plates.
[0028] The one or more connector plates may be any shape and size
so that the one or more pressure plates in conjunction with the
connector body assist in retaining the wear indicator on the
pressure plate. The connector plates may be shaped so that the
connector plates substantially mirror one or more features and/or
one or more recesses in a pressure plate. The one or more connector
plates may have a complementary shape to the one or more features
and/or one or more recesses so that the one or more features and/or
one or more recesses assist in maintaining the wear indicator on
the pressure plate. Preferably, a connector plate extends on each
side of the connector body so that a connector plate extends along
each side of the pressure plate forming a connection with the
pressure plate. The connection plates may be the same size and
shape. Preferably, the connection plates are different sizes. One
connection plate may be planar and one connection plate may be
contoured. The contoured connection plate may be contoured so that
the connection plate grips the pressure plate. The connector plates
may include a retention feature (e.g., a biasing member, a lip, or
both) so that the pressure plates assist in creating a force on the
pressure plate to assist in maintaining the wear indicator on the
pressure plate. The retention feature may project from the
connection plate. The retention feature may be a lip that extends
from the connection plate so that the lip hooks into the recess
and/or feature of the pressure plate and resists the wear indicator
from being removed. The connector plates are free of a retention
feature and/or a biasing member that assists in retaining the wear
indicator an the pressure plate. The connector plates may be free
of active retention features. The one or more connector plates may
be fastened to directly to the pressure plates. The fastener may be
any fastener that forms a secured connection with pressure plate.
The fastener may be removable, may be permanent, or both. The
fastener may be a screw, a rivet, a pin, peened on via button,
protrusion stamped in the pressure plate, or a combination
thereof.
[0029] The connector plates may be made of any material that
maintains its shape and configuration once positioned. The material
of the connector plates may be plastically deformable so that the
connector plate once bent into contact with a pressure plate
maintains its position relative to the pressure plate. The
connector plates may be made of plastic, metal, a polymer, a
natural material, a synthetic material, or a combination thereof.
Preferably, the connector plates are made of stainless steel. The
connector plates and connector body may connect a scraper to the
brake pad.
[0030] The scraper may be any portion of the wear indicator that
contacts the rotor. The scraper may be the only portion of the wear
indicator that extends beyond an edge and/or side of the pressure
plate and/or over the friction material. For example, a portion of
the scraper may extend over the friction material so that when the
friction material is reduced to a predetermined point the scraper
contacts an adjacent surface such as a rotor. The width of the
scraper may be about 5 mm or more, about 5.5 mm or more, about 6 mm
or more, about 6.5 mm or more, or about 7 mm or more. The width of
the scraper may be about 10 mm or less, about 9 mm or less, or
about 7 mm or less. The width of the pressure plate as discussed
herein may be about W.sub.P. The width of the scraper body and the
scraper indicator may be about W.sub.P+0.5 mm or more, about
W.sub.P+1.0 mm or more, about W.sub.P1.2 mm or more, about
W.sub.P+1.5 mm or more, or even about W.sub.P+2.0 mm or more. The
width of the scraper may be about W.sub.P+4 mm or less, about
W.sub.P+3 mm or less, or about W.sub.P+2.5 mm or less.
[0031] The scraper may bias during scraping. For example, the
scraper may elastically deform during a brake apply so that the
scraper produces pressure against an opposing surface (i.e., a
rotor) so that the scraper produces vibration and/or noise that is
transmitted throughout the wear indicator. Preferably, the scraper
is free of a configuration where the scraper biases. For example,
the scraper when in contact with an opposing surface may be
substantially free of movement. The only movement of the scraper
may be elastic deformation due to a material characteristic and/or
vibration caused by contact with the opposing surface. The scraper
may be free of plastic deformation, elastic deformation, or both
during contact with an opposing surface. More preferably, the
scraper is free of any bends, turns, angled portion, biasing
member, or a combination thereof that assist is producing a force
toward the opposing surface so that during a brake apply the
scraper produces a force against the opposing surface.
[0032] The scraper may contact the pressure plate, the friction
material, or both during a running condition, a brake on condition,
or a condition therebetween. Preferably, the scraper is free of
contact with the pressure plate, the friction material, or both
during a brake on condition, a running condition, or a condition
therebetween. The scraper may be separated from the pressure plate,
the friction material, or both by a gap. The gap may be any size so
that the scraper contacts an opposing surface and produces an
audible indication. The gap may be greater than about 0 mm, about
0.1 mm or more, about 0.5 mm or more, or about 1.0 mm or more. The
gap may be about 2.0 mm or less, about 1.5 mm or less, or about 1.2
mm or less. The size of the gap may be greater than about 0 mm to
about 1.5 mm, preferably from about 0.1 mm and about 1.2 mm, and
more preferably between about 0.2 mm and about 1.0 mm. The scraper
may form a cantilever connection with the connector so that the gap
is formed between the pressure plate and the scraper. The scraper
may have a scraper body and a scraper indicator.
[0033] The scraper indicator may be any part that extends over the
friction material and contacts an adjacent surface. The scraper
indicator may entirely reside over the friction material when a
brake pad is new. The scraper indicator may partially extend beyond
the friction material when a brake pad is in a fully worn
condition. The scraper indicator may have any shape so that when
the scraper indicator contacts an adjacent surface the scraper
indicator assists in creating an audible indication. The width of
the wear indicator, the scraper body, or both as discussed herein
may be Y. The largest width of the wear indicator may be where the
scraper includes the scraper indicator. The width of the wear
indicator other than the scraper may be substantially equal to the
width of a pressure plate. The width of the scraper and scraper
indicator may be sufficiently wide to indicate when a predetermined
amount of friction material have been removed (i.e., a worn
condition). The width of the scraper and the scraper indicator may
be about Y+0.5 mm or more, about Y+1.0 mm or more, about Y+1.2 mm
or more, about Y+1.5 mm or more, or even about Y+2 mm or more.
Thus, for example, the scraper body may have a width Y (i.e., be
equal to the rest of the wear indicator) that is substantially
equal to the width of the pressure plate and the scraper indicator
may extend beyond the pressure plate the distance recited in
addition to Y (i.e., about 0.5 mm or more, about 1.0 mm or more,
about 1.2 mm or more etc...) The width of the scraper may be about
Y+4 mm or less, about Y+3 mm or less, or about Y+2.5 mm or
less.
[0034] The scraper indicator may extend along a plane and a contact
portion of the scraper may extend within the plane. For example,
the contact portion may be the largest dimension of the scraper.
The contact portion may be a portion of the scraper that extends
substantially parallel to the pressure plate. The contact portion
of the scraper indicator may be positioned so that the contact
portion is tangential to the circumference of the rotor.
Preferably, the contact portion is positioned so that the contact
portion is angled to form substantially a right angle with the
direction of rotation of the rotor. For example, the contact
portion of the scraper is angled so that a direction of rotation of
the rotor is substantially perpendicular to the contact portion.
The contact portion may be positioned so that the contact portion
extends along a radial length between the center of the rotor and
an edge of the rotor i.e., a radius). In another example, the
contact portion of the scraper may be aligned substantially
radially with the rotor such that the direction of rotor rotation
is substantially perpendicular to the scraper. The scraper may be
aligned substantially radially so that the scraper may lie slightly
at an angle relative to a line that extends radially from the
center of the rotor. The scraper may be aligned at an angle of
about .+-.1.0 degree or more, about .+-.3.0 degrees or more, or
about .+-.5.0 degrees or more from a line that extends radially
from the center of the rotor. The scraper may be aligned at an
angle of about .+-.10 degrees or less, about .+-.8.0 degrees or
less, or about .+-.7.0 degrees or more from a line that extends
radially from the center of the rotor.
[0035] The scraper may have a smooth surface, a grooved surface, a
rough surface, indentations, or a combination thereof. Preferably,
the scraper includes one or more features that assist in creating
an audible indication. More preferably, the scraper includes one or
more grooves in the scraping portion that assist in producing an
audible indication. The one or more grooves may be an absence of
material at a point along the scraping surface. The scraper when in
contact with an adjacent surface may transfer vibration, noise, or
both from the scraper into the scraper body.
[0036] The scraper body may provide a cantilever connection for the
scraper so that the scraper extends over the friction material. The
scraper body may reside substantially entirely over the pressure
plate. The scraper body may be substantially the same width as the
pressure plate. The scraper body may be located between the
connector and the indicator portion. The scraper body may form an
angled connection with the connector, the indicator portion, or
both. The scraper body and the connection, the scraper body and the
indicator portion, or both may form any angle discussed herein for
the one or more bends. The scraper body may connect, to the
indicator portion so that the vibration, noise, or both of the
scraper indicator is transferred to the indicator portion.
[0037] The indicator portion may form a cantilever connection with
the scraper. The indicator portion and the scraper may extend
substantially within the same plane. The indicator portion and the
scraper may form an angle. The indicator portion and the scraper
may form an angle of more than about 0 degrees, about 25 degrees or
more, about 50 degrees or more, preferably about 75 degrees or
more, more preferably about 105 degrees or more, or even more
preferably about 125 degrees or more (i.e., about 139 degrees). The
indicator portion and the scraper may form an angle of about 200
degrees or less, preferably about 180 degrees or less, more
preferably about 160 degrees or less, or even more preferably about
145 degrees or less. Preferably the indicator portion and the
scraper portion are not coplanar. The indicator portion may extend
from the scraper at an angle so that the indicator portion follows
the contours of the pressure plate.
[0038] The indicator portion may contact the pressure plate, the
friction material, or both during a running condition, a brake on
condition, or a condition therebetween. Preferably, the indicator
portion is free of contact with the pressure plate, the friction
material, or both during a brake on condition, a running condition,
or a condition therebetween. More preferably, the indicator portion
may be free of contact with any other component except for the
cantilever connection with the scraper. The indicator portion and
the pressure plate, the friction material, or both may be separated
by a gap. The gap may be any size so that when the scraper contacts
an opposing surface the indicator portion assists in producing an
audible indication. The gap may be greater than about 0 mm, about
0.1 mm or more, about 0.5 mm or more, or about 1.0 mm or more. The
gap may be about 5.0 mm or less, about 3 mm or less, or about 2 mm
or less. The gap may be of a sufficient size so that the indicator
may move up and down, side to side, diagonally, in a circular
fashion, or a combination thereof so that an indication is
produced. The gap may vary along the length of the wear indicator
and/or the indicator portion. The indicator portion may be
substantially planar so that the gap between the pressure plate and
the indicator portion is substantially the same along the length of
the indicator portion.
[0039] The indicator portion may be substantially free of any
bends, curves, angled portions, arcuate portions, or a combination
thereof. The indicator portion may be free of any bends having an
angle of about 45 degrees or more, preferably about 30 degrees or
more, more preferably about 15 degrees or more, or more preferably
about 5 degrees or more. The indicator portion may include a
contour (i.e., the indicator portion may not be planar). The
indicator portion may include one or more bends so that the
indicator portion follows a contour of a pressure plate, the
frequency of the indicator is changed, the noise of the indicator
is changed, or a combination thereof. The indicator portion may
include an indicator body and one or more indicator ends.
[0040] The indicator body may be any part of the indicator portion
that connects to the scraper body. The indicator body may have any
size and shape so that the indicator body assists in producing an
audible indication, connecting the indicator ends to the pressure
plate, or both. The indicator portion may be any size and shape so
that the indicator body extends over the pressure plate. The
indicator portion may extend within only the plane of the pressure
plate. The indicator portion may extend substantially parallel to
the plane of the friction material. The indicator portion may be
any size and shape so that the indicator body is free of extension
beyond the edges of the pressure plate. The indicator portion may
extend beyond an edge of the pressure plate on the edge opposite
the friction material. The indicator portion may have an hour glass
shape. The indicator portion may form a thin neck region. The
indicator portion may include lateral indentations that form the
thin neck portion. The indicator portion may form a narrow arm that
extends between, connects, transfers vibration and/or noise, or a
combination thereof from the scraper body to the indicator
ends.
[0041] The one or more indicator ends may be any part of the wear
indicator that assists in producing an audible indication. The one
or more indicator ends may include a fixed end and a free end. The
fixed end may be connected to the indicator body and the free ends
may extend cantilever over the pressure plate so that the free ends
are free to move during an indication. The free ends during an
indication may move: up, down, side to side, diagonally, in a
circular fashion, or a combination thereof so that the one or more
indicator ends assist in producing an audible indication. The one
or more indicator ends may extend from the scraper so that the free
ends extend from the scraper in an opposite direction of the
direction of rotation of the rotor (i.e., towards the leading end).
Preferably, the one or more indicator ends may extend from the
scraper so that the free ends extend from the scraper in the
direction of rotation of the rotor (i.e., towards the trailing
end).
[0042] There may be one or more indicator ends. Preferably, there
may be at least two indictor ends. The at least two indicator ends
may be substantially discrete from one another, other than a
connection to the indicator body. The one or more indicator ends
may be in any configuration so that the one or more indicator ends
assist in producing an audible indication when the wear indicator
contacts an adjacent surface. However, the indicator ends may
include one or more bends, waves, curves, the like, or a
combination thereof so that the one or more indicator ends extend
out of a single plane. Preferably, the one or more indicator ends
may be substantially planar. For example, the indicator ends may
extend substantially in a single plane. When more than one
indicator ends are present the indicator ends may have any
configuration relative to each other so that: the indicator ends
produce an audible indication, all of the indicator ends are
contained within the dimensions (e.g., width, length, or area) of
the pressure plate, all of the indicator ends converge and attach
to the indicator body, or a combination thereof. The two or more,
indicator ends may be parallel, angled away from each other, angled
towards each other, partially angled towards each other and
partially parallel, or a combination thereof. Preferably, the
indicator ends may be tuning fork shaped. The indicator ends may be
the largest portion of the wear indicator.
[0043] The wear indicator as discussed herein may have a length X.
The length of the indicator ends may be about 0.3.times. or more,
about 0.4.times. or more, or about 0.5.times. or more. The length
of the indicator ends may be about 0.8.times. or less, about
0.7.times. or less, or about 0.65.times. or less. The length of the
one or more indicator ends may be about 5 mm or more, preferably
about 7 mm or more, more preferably about 8 mm or more, or even
more preferably about 10 mm or more. The length of the one or more
indicator ends may be about 25 mm or less, about 20 mm or less, or
about 15 mm or less (i.e., from about 10 mm to about 12 mm).
[0044] The wear indicator may make an audible indication with
sufficient decibels so that a vehicle occupant can hear the audible
indication from inside of the vehicle. The wear indicator may an
audible indication with sufficient decibels so that a vehicle
occupant can hear the audible indication when a radio in the
vehicle is off, on, or both. The wear indicator may make an audible
indication of about 40 decibels or more, about 50 decibels or more,
about 60 decibels or more, about 70 decibels or more, or about 80
decibels or more. The wear indicator may make an audible indication
of about 120 decibels or less, about 100 decibels or less, or about
90 decibels or less.
[0045] The audible indication (e.g., frequency, volume, noise, or a
combination thereof) of the wear indicator may be tuned. The
audible indication may be tuned by adjusting one or more features
of the wear indicator. The audible indication may be tuned by
adjusting one or more of the following: length, width, material
thickness, the number of indicator ends, the shape of the indicator
body, the shape of the scraper indicator, the angle of the scraper
relative to the rotor, the gap size, the angle between the
indicator portion and the scraper, or a combination thereof
[0046] FIG. 1 illustrates a perspective view of one example of a
wear indicator 2. The wear indicator 2 includes a connector 20. The
connector 20 has a connection body 24 with a connection plate 22 on
each side of the connection body 24. The connection plates 22 as
illustrated are different sizes. A scraper 40 is attached to a
connector 20. The scraper 40 includes a scraper body 42 and a
scraper indicator 44. The scraper 40 is connected to an indicator
potion 60 so that the indicator portion 60 extends from the scraper
40. The indicator portion 60 has an indicator body 62 and two
indicator ends 64. The scraper 40 and the indicator portion 60 form
a cantilever connection with the connector 20.
[0047] FIG. 2 illustrates a side view of the wear indicator 2, An
angle (.beta.) is formed between scraper 40 and the indicator
portion 60.
[0048] FIG. 3A illustrates a wear indicator 2. The wear indicator 2
includes a connector 20 a scraper 40 and an indicator 60. The
connector 20 incudes at least two connection plates 22 attached on
opposing sides of a connection body 24. The connection plates 22
extend around both sides of a pressure plate 4 and into a recess
and/or feature 18 (not shown) in the pressure plate 4 so that the
wear indicator 2 is attached to the pressure plate 4. The
connection body 24 is connected to the scraper 40. The scraper 40
and indicator portion 60 and forms a cantilever connection with the
connector 20 so that a gap is formed under the scraper 40 and the
indicator portion 60. The scraper 40 includes a scraper body 42 and
scraper indicator 44. The scraper indicator 44 extends beyond an
edge 16 of the pressure plate 4 so that the scraper indicator 44
contacts a component (not shown) when a sufficient amount of
friction material 6 is removed so that the scraper indicator 44
extends beyond the width (W.sub.P) of the friction material 6 (not
shown) and contacts an adjacent surface (not shown). An indicator
60 is connected to the scraper body 42 and extends away from the
scraper 40 and the connector 20. The indicator 60 includes an
indicator body 62. The indicator body 62 branches to form two
indicator ends 64. As illustrated the two indicator ends 64 are
substantially parallel. The indicator portion 60 as illustrated has
a width (W.sub.I) that is substantially equal to a width (W.sub.P)
of the pressure plate so that the indicator portion 60 does not
overhang the pressure plate 4 on a side of the pressure plate
proximate to the friction material 6.
[0049] FIG. 3B illustrates a side view of a wear indicator 2
connected to a pressure plate 4. The wear indicator 2 extends below
the friction material 6 so that the indicator 60 forms a gap (G)
between the pressure plate 4 and the friction material 6. The
scraper 40 also has a gap (Gs) between the scraper 40 and the
pressure plate 4.
[0050] FIGS. 4A and 4B illustrate an example of peened connection
26. FIG. 4A is a perspective view of wear indicator 2 and the
peened connection 26 between a connection plate 22 and the pressure
plate 4. FIG. 4B illustrates a bottom view of the peened connection
26. As illustrated, the wear indicator 2 includes only one
connection plate 22 and the other side of the connection body 24 is
free of a connection plate 22. The scraper indicator 44 extends
over the friction material 6 a distance (T).
[0051] FIG. 5 illustrates an example of a wear indicator 2
including extended indicator ends 64 having bends 66 that mirror
the shape of the pressure plate 4.
[0052] FIGS. 6A and 6B illustrate the wear indicator 2 connected to
a brake pad 8. FIG. 4A illustrates the front side of the brake pad
8. The wear indicator 2 includes a connection plate 22 extending on
the front side of the pressure plate 4 to assist in connecting the
wear indicator 2 to the brake pad 8. The scraper indicator 44
extends beyond the pressure plate 4 so that a portion of the
scraper indicator extends over the friction material 6. FIG. 4B
illustrates the rear side of the brake pad 8. The wear indicator 2
includes a connection plate 22 extending on the rear side of the
pressure plate 4 to assist in connecting the wear indicator 2 to
the brake pad 8. As illustrated in both FIGS. 4A and 4B the
indicator body 62 and indicator ends 64 extend substantially
parallel, to the pressure plate 4 of the brake pad 8.
[0053] FIG. 7 illustrates a brake system 14. The brake system 14
includes a support bracket 10, a caliper 12, and a rotor 106. The
brake pad 8 is installed in the support bracket 10 and the caliper
12 extends over the brake pad 8. The brake pad 8 includes a wear
indicator 2. The brake pad 8 includes a recess or feature 18 for
assisting in connecting the wear indicator 2 to the brake pads 8.
The rotor 106 rotates in the direction of rotation 108 so that the
rotor first passes through the brake system 14 on a leading side
110 and exits the brake system 14 on a trailing side 112 of the
brake system 14. As illustrated the wear indicator 2 is connected
on the leading side 110 of the brake system. However, the wear
indicator 2 may be located on the leading side 110, the trailing
side 112, or both. The rotor 106 includes a radius (R) that extends
from the center of the rotor to an edge of the rotor 106 and the
radius (R) and a contact surface 46 of the scraper 40 are
substantially parallel.
[0054] FIG. 8 illustrates a vehicle 100 having a brake system 102.
The brake system 102 includes the wear indicator 2 (not shown) of
the teachings herein. During a brake apply, as shown, the wear
indicator produces an audible indication 104.
[0055] Any numerical values recited herein include all values from
the lower value to the upper value in increments of one unit
provided that there is a separation of at least 2 units between any
lower value and any higher value. As an example, if it is stated
that the amount of a component or a value of a process variable
such as, for example, temperature, pressure, time and the like is,
for example, from 1 to 90, preferably from 20 to 80, more
preferably from 30 to 70, it is intended that values such as 15 to
85, 22 to 68, 43 to 51, 30 to 32 etc. are expressly enumerated in
this specification. For values which are less than one, one unit is
considered to be 0.0001, 0.001, 0.01 or 0.1 as appropriate. These
are only examples of what is specifically intended and all possible
combinations of numerical values between the lowest value and the
highest value enumerated are to be considered to be expressly
stated in this application in a similar manner. The use of the
terms "comprising" or "including" to describe combinations of
elements, ingredients, components or steps herein also contemplates
embodiments that consist essentially of the elements, ingredients,
components or steps. By use of the term may herein, it is intended
that any described attributes that "may" be included are
optional.
[0056] Plural elements, ingredients, components or steps can be
provided by a single integrated element, ingredient, component or
step. Alternatively, a single integrated element, ingredient,
component or step might be divided into separate plural elements,
ingredients, components or steps. The disclosure of "a" or "one" to
describe an element, ingredient, component or step is not intended
to foreclose additional elements, ingredients, components or
steps.
* * * * *