Patent Description:
A disc brake having springs is disclosed in <CIT>. <CIT> discloses a cable that extends from a plug to a wear sensor by extending over a first central wire section of a generally T-shaped hold-down spring and under a second central wire section of the hold-down spring.

In at least one embodiment a disc brake assembly is provided. The disc brake assembly includes the features of claim <NUM>.

The sensor assembly may include a second sensor that is disposed on the second brake pad assembly. The wire harness may be electrically connected to the second sensor.

The first brake pad retraction spring may have a coil that defines a coil hole. The wire harness may pass through the coil hole. The brake assembly may further comprise a brake caliper that defines a cavity that receives the first and second brake pad assemblies and a retainer strap that is mounted to the brake caliper and that extends across the cavity and the first and second brake pad assemblies. The coil may engage the retainer strap.

The first brake pad retraction spring may have an anti-rotation feature that is disposed adjacent to the first brake pad assembly or the second brake pad assembly and that defines a hole. The wire harness may pass through the hole.

The coil may encircle an axis. The coil may have first and second coil portions that are arranged along the axis. The wire harness may extend between and be pinched by the first and second coil portions.

The wire harness is attached to the first brake pad retraction spring with an attachment feature that encircles the wire harness and the first brake pad retraction spring.

The attachment feature may be a coil spring that defines a coil spring passage through which the first brake pad retraction spring and the wire harness extend.

The attachment feature may be a coil spring that defines a first coil spring passage through which the first brake pad retraction spring extends and that defines a second coil spring passage through which the wire harness extends.

The first brake pad retraction spring may include first and second arms that extend from the coil. The wire harness may be attached to the first arm and the second arm.

The sensor assembly may include a wireless transmitter and the wire harness may extend from the first sensor to the wireless transmitter. The wireless transmitter may be disposed on the first brake pad retraction spring.

The disc brake assembly may further comprise a second brake pad retraction spring that extends between the first and second brake pad assemblies and that biases the first and second brake pad assemblies away from each other. The wire harness may be attached to the first brake pad retraction spring and the second brake pad retraction spring.

The wire harness may include a first branch that is attached to the first brake pad retraction spring and a second branch that is attached to the second brake pad retraction spring. The first and second brake pad retraction springs may each have a coil and first and second arms that extend from the coil. The first branch may engage the coil of the first brake pad retraction spring and may be attached to the first arm of the first brake pad retraction spring. The second branch may engage the coil of the second brake pad retraction spring and may be attached to the first arm of the second brake pad retraction spring.

The wire harness may include a first branch that is electrically connected to the first sensor and a second branch that is electrically connected to a second sensor that is disposed on the second brake pad assembly. The first branch and the second branch may engage the coil of the first brake pad retraction spring. The first branch and the second branch may be twisted around the first brake pad retraction spring.

The disc brake assembly may further comprise a second brake pad retraction spring that extends between the first and second brake pad assemblies and that biases the first and second brake pad assemblies away from each other. The second branch may engage the second brake pad retraction spring. The first branch may pass through the coil of the first brake pad retraction spring. The second branch may pass through a coil of the second brake pad retraction spring.

Referring to <FIG>, an example of a disc brake assembly <NUM> is shown. The disc brake assembly <NUM> may be provided as part of a vehicle, such as a truck, bus, farm equipment, military transport or weaponry vehicle, or cargo loading equipment for land, air, or marine vessels. In at least one configuration, the disc brake assembly <NUM> may include a brake carrier <NUM>, a brake caliper <NUM>, at least one brake pad assembly <NUM>, one or more pad springs <NUM>, a retainer strap <NUM>, and one or more brake pad retraction springs <NUM>. The disc brake assembly <NUM> may also include a sensor assembly <NUM> an example of which is best shown in <FIG>.

The brake carrier <NUM> may facilitate mounting of the disc brake assembly <NUM>. For instance, the brake carrier <NUM> may be fixedly mounted to a component of the vehicle, such as an axle assembly or a knuckle. The brake carrier <NUM> may receive and support the brake pad assemblies <NUM> and may include an opening through which a brake rotor <NUM> may extend. As such, the brake carrier <NUM> may straddle the brake rotor <NUM> and may help position brake pad assemblies <NUM> on opposite sides of the brake rotor <NUM>.

The brake caliper <NUM> may be mounted to the brake carrier <NUM> and may support various components of the disc brake assembly <NUM>. In addition, the brake caliper <NUM> may help position the brake pad assemblies <NUM> with respect to the brake rotor <NUM> to facilitate braking of the vehicle as will be discussed in more detail below. In at least one configuration, the brake caliper <NUM> may include a caliper housing <NUM> and a caliper bridge <NUM>.

Referring to <FIG> and <FIG>, the caliper housing <NUM> may be moveably disposed on the brake carrier <NUM>. For example, the caliper housing <NUM> may be slidable along a pair of guide pins that may be fixedly disposed on the brake carrier <NUM>. The caliper housing <NUM> may receive or support various components that may facilitate actuation of a brake pad assembly <NUM>. For instance, the caliper housing <NUM> may support at least one tappet <NUM> that may protrude from an internal chamber of the caliper housing <NUM>.

Referring to <FIG>, a tappet <NUM> may extend from the caliper housing <NUM> toward the brake rotor <NUM> to engage a brake pad assembly <NUM>. The tappet <NUM> may be moveable toward and away from the brake rotor <NUM>. For instance, an actuator may extend the tappet <NUM> to actuate a brake pad assembly <NUM> that is disposed between the caliper housing <NUM> and the brake rotor <NUM> into engagement with the brake rotor <NUM>. A reaction force may then move the caliper housing <NUM> and caliper bridge <NUM> with respect to the brake carrier <NUM> to actuate a brake pad assembly <NUM> that is disposed between the caliper bridge <NUM> and the brake rotor <NUM> into engagement with an opposite side of the brake rotor <NUM> to help slow rotation of the brake rotor <NUM> and an associated vehicle wheel.

The caliper bridge <NUM> may be fixedly positioned with respect to the caliper housing <NUM>. The caliper bridge <NUM> may be integrally formed with the caliper housing <NUM> or may be a separate component that is mounted to the caliper housing <NUM>. For example, the caliper bridge <NUM> may be coupled or secured to the caliper housing <NUM> with one or more fasteners, such as bolts. In at least one configuration, the caliper bridge <NUM> may cooperate with the caliper housing <NUM> to define a cavity <NUM>.

The cavity <NUM> may at least partially receive the brake pad assemblies <NUM> and the brake rotor <NUM>. The cavity <NUM> may be configured as a large through hole that may be encircled by the brake caliper <NUM>. A portion of the brake carrier <NUM> may extend into the cavity <NUM> and may help position the brake pad assemblies <NUM>. A brake pad assembly <NUM> may be inserted into the cavity <NUM> and installed on the brake carrier <NUM> or removed from the cavity <NUM> and the brake carrier <NUM> when the retainer strap <NUM> is removed.

Referring primarily to <FIG> and <FIG>, a pair of brake pad assemblies <NUM> may be received in the brake carrier <NUM> and the cavity <NUM>. The brake pad assemblies <NUM> may be disposed on opposite sides of the brake rotor <NUM> and may have similar or identical configurations. For convenience in reference, the brake pad assembly <NUM> that is disposed between the brake rotor <NUM> and the tappet <NUM> may be referred to as an inboard brake pad assembly while the brake pad assembly <NUM> that is disposed between the brake rotor <NUM> and the caliper bridge <NUM> may be referred to as an outboard brake pad assembly. Also for convenience in reference, the brake pad assemblies <NUM> may be referred to as a "first brake pad assembly" and a "second brake pad assembly" below. The first and second brake pad assemblies may be the inboard and outboard brake pad assemblies, respectively, or vice versa. In at least one configuration, a brake pad assembly <NUM> may include a backplate <NUM> and friction material <NUM>.

The backplate <NUM> may be a structural member of the brake pad assembly <NUM>. The backplate <NUM> may be configured as a generally flat plate and may be made of any suitable material, such as a metal alloy. The tappet <NUM> may engage the backplate <NUM> of the inboard brake pad assembly <NUM>. For instance, the tappet <NUM> may engage a side of the backplate <NUM> that may face away from the brake rotor <NUM> and that may be disposed opposite the friction material <NUM>. The backplate <NUM> of the outboard brake pad assembly <NUM> may engage the caliper bridge <NUM>. The backplate <NUM> may also include a first hole <NUM> and a second hole <NUM> that may facilitate mounting of a brake pad retraction spring <NUM>. In at least one configuration, the first hole <NUM> and the second hole <NUM> may be disposed above the friction material <NUM>.

The friction material <NUM> may be disposed on a side of the backplate <NUM> that may face toward the brake rotor <NUM>. The friction material <NUM> may contact the brake rotor <NUM> during vehicle braking.

The pad spring <NUM>, if provided, may be at least partially disposed in the cavity <NUM>. The pad spring <NUM> may exert a biasing force against a component that is received in the cavity <NUM> such as a brake pad assembly <NUM> or the tappet <NUM>. In the configuration shown, two pad springs <NUM> are illustrated; however, it is contemplated that a different number of pad springs <NUM> may be provided. The pad springs <NUM> may be spaced apart from each other and may extend from the retainer strap <NUM> into the cavity <NUM>. For instance, one pad spring <NUM> may extend from the retainer strap <NUM> to the inboard brake pad assembly <NUM> and another pad spring <NUM> may extend from the retainer strap <NUM> to the outboard brake pad assembly <NUM>.

The retainer strap <NUM> may extend across the brake pad assemblies <NUM> and the cavity <NUM> of the brake caliper <NUM> to help retain the brake pad assemblies <NUM> in the brake carrier <NUM> when the retainer strap <NUM> is secured to the brake caliper <NUM>. The retainer strap <NUM> may be removably mountable to the brake caliper <NUM>. For instance, a first end of the retainer strap <NUM> may be mounted to the caliper housing <NUM> while a second end of the retainer strap <NUM> that is disposed opposite the first end may be mounted to the caliper bridge <NUM>. The second end may be secured to the caliper bridge <NUM> in any suitable manner, such as with a fastener <NUM> like a bolt. The retainer strap <NUM> may be removed from the brake caliper <NUM> to facilitate removal or replacement of a brake pad assembly <NUM> and may be installed on the brake caliper <NUM> to inhibit removal of a brake pad assembly <NUM>. The retainer strap <NUM> may engage or contact a brake pad assembly <NUM>, a pad spring <NUM>, a brake pad retraction spring <NUM>, or combinations thereof when the retainer strap <NUM> is installed and secured to the brake caliper <NUM>.

Referring primarily to <FIG> and <FIG>, at least one brake pad retraction spring <NUM> may be provided with the disc brake assembly <NUM>. A brake pad retraction spring <NUM> may facilitate retraction of the brake pad assemblies <NUM> away from the brake rotor <NUM> when braking force is not applied. As such, a brake pad retraction spring may bias the brake pad assemblies <NUM> away from the brake rotor <NUM> and away from each other. For instance, first and second brake pad retraction springs <NUM> may be provided that may extend in opposite lateral directions from the retainer strap <NUM>, or to the left and right from the perspective shown in <FIG>. The brake pad retraction spring <NUM> may extend between the inboard brake pad assembly <NUM> and the outboard brake pad assembly <NUM>. For example, a brake pad retraction spring <NUM> may extend from the backplate <NUM> of the inboard brake pad assembly <NUM> to the backplate <NUM> of the outboard brake pad assembly <NUM>.

The brake pad retraction spring <NUM> may be provided in various configurations. As an example and as is best shown with reference to <FIG> and <FIG>, the brake pad retraction spring <NUM> may include a first end <NUM>, a second end <NUM>, a coil <NUM>, a first arm <NUM>, a second arm <NUM>, and optionally one or more anti-rotation features <NUM>.

The first end <NUM> may be mounted to a brake pad assembly <NUM>. For example, the first end <NUM> of the brake pad retraction spring <NUM> may be inserted into and may be received in the first hole <NUM> of the backplate <NUM> of a brake pad assembly <NUM>. In at least one configuration, the first end <NUM> may not be coplanar with the coil <NUM>, the first arm <NUM>, the anti-rotation feature <NUM>, or combinations thereof when the brake pad retraction spring <NUM> is installed or when the brake pad retraction spring <NUM> is not installed and is in a free state or uncompressed state.

The second end <NUM> may be disposed opposite the first end <NUM>. The second end <NUM> may be mounted to the other brake pad assembly <NUM>. For example, the second end <NUM> of the brake pad retraction spring <NUM> may be inserted into and may be received in the second hole <NUM> of the backplate <NUM> of another brake pad assembly <NUM>. In at least one configuration, the first end <NUM> may not be coplanar with the coil <NUM>, the second arm <NUM>, the anti-rotation feature <NUM>, or combinations thereof when the brake pad retraction spring <NUM> is installed or when the brake pad retraction spring <NUM> is not installed and is in a free state or uncompressed state.

In configurations that have two brake pad retraction springs <NUM>, the first and second ends <NUM>, <NUM> of one brake pad retraction spring <NUM> may be mounted to first and second brake pad assemblies <NUM>, <NUM>, respectively, while the first and second ends <NUM>, <NUM> of the other brake pad retraction spring <NUM> may be mounted to the second and first brake pad assemblies <NUM>, <NUM>, respectively.

The coil <NUM> may be disposed between the first end <NUM> and the second end <NUM>. The coil <NUM> may engage the retainer strap <NUM>. For instance, the coil <NUM> may contact a side of the retainer strap <NUM> that may face toward the brake rotor <NUM> and the cavity <NUM>. As such, the retainer strap <NUM> may inhibit movement of the coil <NUM> away from the brake rotor <NUM> or rotation of the brake pad retraction spring <NUM> away from the brake rotor <NUM>. As is best shown in <FIG>, the coil <NUM> may define a coil hole <NUM> that may extend around and may encircle an axis <NUM>. The coil hole <NUM> and the axis <NUM> may be encircled by one or more turns or spirals that make up the coil <NUM>. For instance, as is best shown with reference to <FIG>, the coil <NUM> may include a first coil portion <NUM> and a second coil portion <NUM> that may at least partially define the coil hole <NUM> and that may be contiguous with each other. The first coil portion <NUM> and the second coil portion <NUM> may be stacked or arranged along the axis <NUM> such that the first coil portion <NUM> may be disposed above the second coil portion <NUM>.

Referring to <FIG>, the first arm <NUM> may extend from the coil <NUM> toward the first end <NUM>. In at least one configuration, the first arm <NUM> may include an arm bend <NUM> that may be disposed between and may be spaced apart from the coil <NUM> and the first end <NUM>. In the configuration shown, the first arm <NUM> is provided without an anti-rotation feature <NUM>; however, it is contemplated that an anti-rotation feature may also be provided with the first arm <NUM>.

The second arm <NUM> may be spaced apart from the first arm <NUM>. The second arm <NUM> may extend from the coil <NUM> toward the second end <NUM>. The second arm <NUM> may have the same configuration or a different configuration than the first arm <NUM>. In the configuration shown, an anti-rotation feature <NUM> is provided with the second arm <NUM>.

One or more anti-rotation features <NUM> may optionally be provided with the brake pad retraction spring <NUM>. The anti-rotation feature <NUM> may be disposed between the coil <NUM> and the first end <NUM>, between the coil <NUM> and the second end <NUM>, or both. The anti-rotation feature <NUM> may engage a brake pad assembly <NUM>, a pad spring <NUM>, or both to inhibit rotation of the brake pad retraction spring <NUM> toward the brake rotor <NUM>, thereby preventing the brake pad retraction spring <NUM> from contacting the brake rotor <NUM>. For example, an anti-rotation feature <NUM> may be disposed above at least a portion of a corresponding brake pad assembly <NUM> and may contact the corresponding brake pad assembly <NUM> to inhibit rotation of the coil <NUM> away from the retainer strap <NUM> and toward the brake rotor <NUM>. In the configurations shown in <FIG> and <FIG>, the anti-rotation feature <NUM> is depicted as being a coil. In such a configuration, the coil of the anti-rotation feature <NUM> may define a hole <NUM> that may be encircled by one or more turns or spirals that make up the coil. The anti-rotation feature <NUM> may be disposed between the pad spring <NUM> and the backplate <NUM>. Alternatively, the pad spring <NUM> or a portion thereof may be disposed between the backplate <NUM> and the anti-rotation feature <NUM>.

Referring to <FIG>, an example of a sensor assembly <NUM> shown. The sensor assembly <NUM> may be configured to detect and communicate a condition or attribute of the disc brake assembly <NUM>. The sensor assembly <NUM> may include one or more sensors <NUM> and a wire harness <NUM>. In addition, one or more attachment features <NUM> may be associated with the sensor assembly <NUM>.

A sensor <NUM> may be configured to provide a signal indicative of one or more attributes associated with the disc brake assembly <NUM>. As an example, the sensor <NUM> may detect or provide a signal indicative of wear of the friction material <NUM>. In the configuration shown in <FIG>, four sensors <NUM> are shown; however, it is contemplated that a different number of sensors may be provided. The sensor <NUM> may be located in any suitable location. In the configuration shown, each sensor <NUM> is disposed on the backplate <NUM> of a brake pad assembly <NUM> and protrudes from the backplate <NUM> toward the brake rotor <NUM>. Upon sufficient wear of the friction material <NUM>, the sensor <NUM> may contact the brake rotor <NUM> during braking and provide a signal that may be indicative of wear of the friction material <NUM> and that the brake pad assembly <NUM> should be replaced. It is contemplated that the signal may be generated by the sensor <NUM> or may be associated with opening or closing an electrical circuit. For instance, the engagement of the brake rotor <NUM> with the sensor <NUM> may sever or otherwise disconnect a normally continuous electrical circuit, resulting in a change to one or more electrical attributes, such as current or voltage, which may be detected or identified by an electronic controller that may receive the signal in a manner known by those skilled in the art.

The wire harness <NUM> may be electrically connected to the sensor <NUM>. The wire harness <NUM> may include one or more conductors or wires that may extend from one or more sensors <NUM>.

As an overview, a wire harness may be provided with sufficient length to move with a brake pad assembly when braking is applied and released. As a result, the wire harness may flex, bend, or otherwise move during braking. The wire harness may also move in response to vibrations that may be transmitted to the disc brake assembly when the vehicle is in motion. A wire harness may be susceptible to damage during operation of the disc brake assembly if improperly configured. For instance, the wire harness may be damaged if it moves into contact with the brake rotor or becomes pinched between a brake pad assembly and the brake rotor. Potential damage to the wire harness may be avoided by attaching the wire harness to one or more brake pad retraction springs.

The wire harness <NUM> may be attached to a brake pad retraction spring <NUM> with one or more attachment features <NUM>, may be directly attached to a brake pad retraction spring <NUM>, or combinations thereof. An attachment feature <NUM> may be separate from the brake pad retraction spring <NUM> and the wire harness <NUM>. Direct attachment may utilize the brake pad retraction spring <NUM> or the wire harness <NUM> itself to facilitate attachment. Both types of attachment techniques will now be discussed.

Referring to <FIG>, an attachment feature <NUM> may attach the wire harness <NUM> to a brake pad retraction spring <NUM> in a manner that permits limited movement of the wire harness <NUM> with respect to the brake pad retraction spring <NUM> and/or the attachment feature <NUM> or that prevents movement of the attached portion of the wire harness <NUM> with respect to the brake pad retraction spring <NUM> and/or the attachment feature <NUM>. An attachment feature <NUM> may have any suitable configuration. Referring to <FIG>, some examples of attachment features <NUM> are shown.

In <FIG>, an attachment feature <NUM> is shown that may be configured as a tubular structure that may partially or completely encircle the wire harness <NUM>, the brake pad retraction spring <NUM>, or both. The attachment feature <NUM> may be tape that may have an adhesive backing, tubing that may or may not be split, a clip, tie, strap, hook and loop fastener, or the like. It is also contemplated that the attachment feature may be an adhesive and may not completely encircle the wire harness <NUM>, the brake pad retraction spring <NUM>, or both.

In <FIG>, the attachment feature <NUM> is configured as a coil spring. The coil spring may define a coil spring passage <NUM> through which the brake pad retraction spring <NUM> and the wire harness <NUM> may extend. For instance, the coil spring may extend in a spiral around the brake pad retraction spring <NUM> and the wire harness <NUM> and thus may define the coil spring passage <NUM> within the spiral.

In <FIG>, the attachment feature <NUM> is again configured as a coil spring that defines a coil spring passage <NUM>. The brake pad retraction spring <NUM> and the wire harness <NUM> may extend together through a portion of the coil spring passage <NUM> to help retain the wire harness <NUM> upon the brake pad retraction spring <NUM>. However, a portion of the coil spring and the coil spring passage <NUM> may receive the wire harness <NUM> but not the brake pad retraction spring <NUM>, thereby exerting a biasing force on the wire harness <NUM>. As a result, the coil spring and portion of the coil spring passage <NUM> that receives the wire harness <NUM> but not the brake pad retraction spring <NUM> may help control movement of the portion of the wire harness <NUM> that is received in the coil spring passage <NUM> by itself by exserting a biasing force on the wire harness <NUM>, such as may occur when the coil spring attempt to move to a straightened condition. As such, the coil spring may help route the wire harness <NUM> away from the brake rotor <NUM> or a location where the wire harness <NUM> may be pinched between moveable components of the disc brake assembly <NUM>. The coils of attachment feature <NUM> and the coil spring passage <NUM> may be a constant size or may have different sizes. For instance, the coil spring passage <NUM> may be larger in a region that receives the wire harness <NUM> and the brake pad retraction spring <NUM> as compared to a region that receives only one of these components.

In <FIG>, two attachment features <NUM> are shown that are configured as coil springs. The coil spring may define two or more coil spring passages. At least one coil spring passage may receive the brake pad retraction spring <NUM> but not the wire harness <NUM> while another coil spring passage may receive the wire harness <NUM> but not the brake pad retraction spring <NUM>. In the configuration shown, the coil spring may define a first coil spring passage <NUM>, a second coil spring passage <NUM>', and optionally a third coil spring passage <NUM>". The brake pad retraction spring <NUM> may extend through the first coil spring passage <NUM>. The wire harness <NUM> may extend through the second coil spring passage <NUM>' and the third coil spring passage <NUM>".

The second coil spring passage <NUM>' may be defined by coils of the coil spring that may be offset from the coils that define the first coil spring passage <NUM>. As such, the second coil spring passage <NUM>' may be disposed along a different coil spring axis than the first coil spring passage <NUM>. In at least one configuration, the second coil spring passage <NUM>' may extend from a first end of the coil spring.

The third coil spring passage <NUM>" may be defined by coils of the coil spring that may be offset from the coils that define the first coil spring passage <NUM>. As such, the third coil spring passage <NUM>" may be disposed along a different coil spring axis than the first coil spring passage <NUM>. In at least one configuration, the third coil spring passage <NUM>" may extend from a second end of the coil spring that may be disposed opposite the first end.

Attachment features <NUM> are represented generically in <FIG> and <FIG>. It is to be understood that the generic representation of an attachment feature may represent any of the attachment features discussed herein. It is also to be understood that the generic representation of an attachment feature may represent a single attachment feature or multiple attachment features.

Referring to <FIG>, <FIG>, and <FIG> some examples of directly attaching the wire harness <NUM> to a brake pad retraction spring <NUM> are shown. Direct attachment may occur without utilizing an attachment feature that is separate from the brake pad retraction spring <NUM> and the wire harness <NUM>. For instance, the brake pad retraction spring <NUM>, the wire harness <NUM>, or both may be configured to limit movement or prevent movement of the wire harness <NUM> with respect to the brake pad retraction spring <NUM> without a separate attachment feature.

In <FIG>, the coil <NUM> may be configured to engage and pinch the wire harness <NUM>. For instance, the wire harness <NUM> may extend between the first coil portion <NUM> and the second coil portion <NUM>.

In <FIG>, the wire harness <NUM> may pass through the coil hole <NUM> through the opening defined by the first coil portion <NUM> (e.g., from above the coil <NUM> from the perspective shown) or alternatively pass through the opening defined by the second coil portion <NUM> (e.g.,, from below the coil <NUM> from the perspective shown).

In <FIG>, the wire harness <NUM> may pass between the first coil portion <NUM> and the second coil portion <NUM> without entering the coil hole <NUM> through the openings defined by the first coil portion <NUM> and the second coil portion <NUM>.

It is also contemplated that the coil shown in <FIG> may be the coil of an anti-rotation feature <NUM> rather than the coil <NUM> from which the first arm <NUM> and the second arm <NUM> of the brake pad retraction spring <NUM> extend.

In <FIG> and <FIG>, the wire harness <NUM> may be twisted around, looped through, or tied to the brake pad retraction spring <NUM> to limit movement of the wire harness <NUM> with respect to the brake pad retraction spring <NUM>. It is also contemplated that the wire harness <NUM> may be twisted around, looped through, or tied to itself. As such, the wire harness <NUM> may attach itself to the brake pad retraction spring <NUM>.

Referring to <FIG>, an example of limiting movement of the wire harness <NUM> by passing the wire harness <NUM> through the coil hole <NUM> is shown. The size of the coil hole <NUM> may dictate the degree by which movement of the wire harness <NUM> is restricted. For instance, a smaller diameter coil hole <NUM> may limit movement by a greater degree than a larger diameter hole due to the reduced area provided by a smaller diameter hole. In <FIG>, the wire harness <NUM> is not pinched by the coil <NUM>. It is also contemplated that the coil <NUM> shown in <FIG> may be a coil that is provided with an anti-rotation feature <NUM>. In such a configuration, the wire harness <NUM> may pass through the hole <NUM> of an anti-rotation feature <NUM>.

Referring to <FIG> and <FIG>, examples of routing and attaching the wire harness <NUM> to one or more brake pad retraction springs <NUM> will now be discussed. It is to be understood that the wire harness <NUM> may be attached to a brake pad retraction spring <NUM> with one or more attachment features <NUM>, which may be configured as previously discussed. Moreover, the wire harness <NUM> may be directly attached to a brake pad retraction spring <NUM> using any of the direct attachment configurations previously discussed. The direct attachment techniques may be substitutes for each other in the configurations discussed below.

In <FIG> and <FIG>, the pad springs <NUM> and the retainer strap <NUM> are simplified and shown in phantom to more clearly depict the sensor assembly <NUM>. In <FIG>, the sensor assembly is designated with the number <NUM> along with a superscript letter for convenience in reference. A brake pad retraction spring <NUM> and the sensor assembly <NUM> may be positioned below the pad spring <NUM>, the retainer strap <NUM>, or both in these examples.

Referring to <FIG>, the wire harness <NUM> may be routed from the inboard side of the disc brake assembly <NUM> to one or more sensors <NUM>. The wire harness <NUM> may then be routed laterally along the top of a brake pad assembly <NUM> in a direction that may extend away from the retainer strap <NUM> and toward an end of a brake pad retraction spring <NUM>. The wire harness <NUM> may then be routed along an arm of the brake pad retraction spring <NUM>. For example, a portion of the wire harness <NUM> may be routed along the second arm <NUM> of the brake pad retraction spring <NUM> that is located to the left of the retainer strap <NUM> from the perspective shown while a portion of the wire harness <NUM> may be routed along the first arm <NUM> of the brake pad retraction spring <NUM> that is located to the right of the retainer strap <NUM>. One or more attachment features <NUM> may attach or secure the wire harness <NUM> to a corresponding arm. The wire harness <NUM> may then pass through the coil hole <NUM> of the coil <NUM> and may extend to the other arm of the brake pad retraction spring <NUM>. For instance, a portion of the wire harness <NUM> may be routed along the first arm <NUM> of the brake pad retraction spring <NUM> that is located to the left of the retainer strap <NUM> while a portion of the wire harness <NUM> may be routed along the second arm <NUM> of the brake pad retraction spring <NUM> that is located to the right of the retainer strap <NUM> from the perspective shown. The same attachment feature <NUM> or another attachment feature <NUM> may attach or secure the wire harness <NUM> to that arm. The wire harness <NUM> may then be routed along the top of another brake pad assembly <NUM> to another sensor <NUM>. The wire harness <NUM> may also pass through the hole <NUM> of an anti-rotation feature <NUM> if an anti-rotation feature <NUM> is provided with a brake pad retraction spring <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>A is shown that is the similar to that shown in <FIG>. In this configuration, the wire harness <NUM> may originate or start proximate the retainer strap <NUM>. For instance, the wire harness <NUM> may branch apart from a location that is located over the brake rotor <NUM> and/or the retainer strap <NUM>. Originating or starting the wire harness branches between the brake pad assemblies <NUM> or over the brake rotor <NUM> may allow branches of the wire harness <NUM> to travel or move approximately equal distances. As a result, at least one wire harness branch may be provided with a shorter length as compared to a wire harness that does not originate or start over the brake rotor <NUM>. For instance, the configuration in <FIG> employs longer wire harness branches that are routed from an inboard sensor <NUM> (disposed closest to the top of <FIG> from the perspective shown) to an outboard sensor <NUM> (disposed closest to the bottom of <FIG> from the perspective shown). The increased length of these wire harness branches provides additional opportunities for the wire harness <NUM> to be pinched or potentially misrouted. In addition, the wire harness branch that is routed to the outboard sensor <NUM> must have a greater length to accommodate not only its routing path but also movement of the brake pad retraction spring <NUM> but also the movement of the caliper bridge <NUM> and the outboard brake pad assembly <NUM> with respect to the caliper housing <NUM> when braking is applied or released. In the configuration in <FIG>, the wire harness <NUM> may or may not pass through the coils <NUM> and may or may not be pinched by the coils <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>B is shown that is the same as that shown in <FIG> except that the wire harness <NUM> does not pass through the coils <NUM>. Instead, the wire harness <NUM> bypasses the coils <NUM> and extends along an arc from one arm of the brake pad retraction spring <NUM> to another arm of the brake pad retraction spring <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>C is shown that is similar to that shown in <FIG>. In this configuration, the sensor assembly <NUM>C includes a wireless transmitter <NUM>. One or more branches <NUM>, <NUM> of the wire harness <NUM> may extend from the wireless transmitter <NUM> to one or more sensors <NUM>. The wireless transmitter <NUM> may wirelessly transmit to or communicate with a controller or control system that may be provided with the vehicle in a manner known by those skilled in the art. For instance, the wireless transmitter <NUM> may operate using similar communication principles as that associated with a wireless tire pressure sensor. The wireless transmitter <NUM> may be disposed in any suitable location. For instance, wireless transmitter may be disposed on the retainer strap <NUM> or the brake pad retraction spring <NUM>. For example, the wireless transmitter <NUM> may be disposed on the coil <NUM> of a brake pad retraction spring <NUM>. It is also contemplated that a wireless transmitter <NUM> may be provided with the other sensor assembly configurations and wire harness routings described herein.

In <FIG>, <FIG>, and <FIG>, it is contemplated that multiple sensors and associated branches of the wire harness <NUM> may be deleted. For instance, the sensors <NUM> to the left of the retainer strap <NUM> and portions of the wire harness <NUM> that extend from these sensor <NUM> may be deleted or the sensors <NUM> to the right of the retainer strap <NUM> and portions of the wire harness <NUM> that extend from these sensor <NUM> may be deleted. In such configurations, the wire harness <NUM> may be attached to a single brake pad retraction spring <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>D is shown in which the wire harness <NUM> is attached to multiple brake pad retraction springs <NUM>. For instance, the wire harness <NUM> may have a first branch <NUM> that may be attached to a first brake pad retraction spring <NUM> and a second branch <NUM> that may be attached to a second brake pad retraction spring <NUM>. A branch may be attached to an arm of a corresponding brake pad retraction spring <NUM> with an attachment feature <NUM> as shown or may be directly attached as previously discussed.

Referring to <FIG>, a configuration of a sensor assembly <NUM>E is shown that is similar to as that shown in <FIG>. In this configuration, the first branch <NUM> and the second branch <NUM> may pass through or may be pinched by coils <NUM> of different brake pad retraction springs <NUM>. For instance, the first branch <NUM> may pass through the coil <NUM> of one brake pad retraction spring <NUM> and may be attached to an arm of that brake pad retraction spring <NUM> while the second branch <NUM> may pass through or may be pinched by the coil <NUM> of the other brake pad retraction spring <NUM> and may be attached to an arm of that brake pad retraction spring <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>F is shown in which the wire harness <NUM> is attached to one brake pad retraction spring <NUM>. For instance, the first branch <NUM> and the second branch <NUM> may be pinched and secured by the coil <NUM> of a brake pad retraction spring <NUM> in a location that may be aligned with the brake rotor <NUM>. The first branch <NUM> may extend from the coil <NUM> to one sensor <NUM> while the second branch <NUM> may extend from the coil <NUM> to another sensor <NUM>. The sensors <NUM> may be disposed on different brake pad assemblies <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>' is shown in which the wire harness <NUM> may be twisted or tied to one or more brake pad retraction springs <NUM>. For instance, the first branch <NUM> and the second branch <NUM> of the wire harness <NUM> may be twisted around or tied to the same brake pad retraction spring <NUM>, which may be the brake pad retraction spring <NUM> that extends to the right of the retainer strap <NUM> from the perspective shown. The first branch <NUM> and the second branch <NUM> may extend to and may engage the coil <NUM> of the same brake pad retraction spring <NUM>. The first branch <NUM> may be pinched by or may pass through the coil <NUM> before extending to a sensor <NUM>. Moreover, the first branch <NUM> may extend to a sensor <NUM> without engaging the other brake pad retraction spring <NUM>. The second branch <NUM> may also extend to the coil <NUM> of the brake pad retraction spring <NUM> and then may extend to the other brake pad retraction spring <NUM>. For instance, the second branch <NUM> may extend from the coil <NUM> of the right brake pad retraction spring <NUM> to the coil <NUM> of the left brake pad retraction spring <NUM> from the perspective shown. The second branch <NUM> may be pinched by or may pass through the coil <NUM> of the other brake pad retraction spring <NUM>. Then, the second branch <NUM> may be twisted around or may be tied to an arm of the other brake pad retraction spring <NUM> before extending to a corresponding sensor <NUM>.

Referring to <FIG>, a configuration of a sensor assembly <NUM>H is shown that is similar to that shown in <FIG>. In this configuration, the first branch <NUM> is pinched by the coil <NUM> of one brake pad retraction spring while the second branch <NUM> is pinched by the same coil <NUM> as well as the coil <NUM> of the other brake pad retraction spring.

Claim 1:
A disc brake assembly (<NUM>) comprising:
first and second brake pad assemblies (<NUM>, <NUM>);
a first brake pad retraction spring (<NUM>) that extends between the first and second brake pad assemblies (<NUM>, <NUM>) and that biases the first and second brake pad assemblies (<NUM>, <NUM>) away from each other; and
a sensor assembly (<NUM>) that includes:
a first sensor (<NUM>) that is disposed on the first brake pad assembly (<NUM>); and
a wire harness (<NUM>) that is electrically connected to the first sensor (<NUM>) and characterized in that said wire harness is attached to the first brake pad retraction spring (<NUM>) with an attachment feature (<NUM>) that encircles the wire harness (<NUM>) and the first brake pad retraction spring (<NUM>).