Patent Description:
Bicycles have been used for recreation, transportation, and sporting competition for decades, and can be found in all types of environments (e.g., urban, suburban, and rural). What started out as a relatively simple assembly of components has evolved into more complex forms as bicycles have been adapted from general use (e.g., transportation, exercise) to more specific niches (e.g., Olympic-style track racing, BMX-style racing, crosscountry cycling, etc.).

As bicycle use has changed, the cycling industry has adapted and improved various components of the bicycle in order to meet the evolving needs of the cycling public. A bicycle rear derailleur is one such component. The purpose of a rear derailleur is to assist in changing the speed of a bicycle by selectively moving a bicycle chain between gears of a cassette located near a rear wheel of the bicycle. A typical rear derailleur has a base member connected to the bicycle near the rear wheel, a chain cage (or chain guide) engaging the bicycle chain, and a movable member connecting the base member and the chain cage so as to move the chain guide laterally relative to the base member. Movement of the chain cage moves the bicycle chain between the gears of the gear cassette. A rider is able to shift gears due to a shift control device (or shifter) mounted on or near the bicycle's handlebar. One end of a control cable running down the length of the bicycle is connected to the shift control device and the other end of the control cable is connected the rear derailleur. The shift control device adjusts the amount of tension on the control cable. The shift control device allows the rider to pull (increase tension) or release (decrease tension) the control cable. An increase or decrease in tension on the control cable determines the direction on the gear cassette in which the bicycle chain moves (i.e., from lower gear to higher gear or from higher gear to lower gear). Increasing tension on the control cable causes the chain cage to laterally move in one direction relative to the base member (which, in turn, moves the bicycle chain in that same direction), while releasing tension on the control cable causes the chain cage to laterally move in another direction relative to the base member (generally the opposite direction the chain cage moves in when tension is increased). Thus, the chain cage (and bicycle chain) can be moved laterally by increasing or decreasing tension on the control cable.

During use, a bicycle can be ridden over a variety of surfaces and terrains including, without limitation, smooth surfaces (e.g., paved surfaces), rough surfaces (e.g., dirt roads, off-road terrain), and the like that can subject the bicycle to various conditions including, without limitation, bouncing, vibration, and the like. There may be hazards including, without limitation, potholes, rocks, and the like. These various conditions and hazards can impact the bicycle in various ways including, without limitation, causing a bicycle rider to crash, causing the bicycle chain to become disengaged from the gear cassette, causing the control cable to become disconnected from the rear derailleur, or the like. For example, when the bicycle is moving on a rough surface, uncontrolled movement of the chain cage can result in the chain cage moving back and forth between the direction of chain tensioning and in the opposite direction. This can result in the bicycle chain bouncing to the extent the bicycle chain becomes disengaged from the chain cage and/or the gear cassette.

Different types of rear derailleurs have been proposed that can move a bicycle chain between gears of a cassette. However, such rear derailleurs have their limitations and can always be improved. <CIT> discloses a rear derailleur provided with an arcuate cable entraining surface which substantially reduces the variation and magnitude of the actuation ratio between control cable linear displacement and movement of the derailleur p-knuckle. A b-knuckle flange militates against the derailment of the drive chain from the upper guide wheel while permitting maximum lateral flexing of the drive chain during shifting between sprockets on the freewheel. A rigid arcuate surface may be provided as an extension of the b-knuckle in replacement of a segment of a Bowden cable housing to obviate the accumulation of water and foreign matter. Said rear derailleur corresponding to the features of the preamble of claim <NUM>. <CIT> discloses an improved rear derailleur for changing the gear ratio of a bicycle is disclosed. It includes a fixed member, a movable member, a parallelogram mechanism connecting the fixed member with the movable member, and a cable adjusting screw which is screwed to a screw socket fixed on the fixed member. The cable adjusting screw is connected to a first end of a cable, wherein the cable has a second end fixed to a movable member. The cam member comprises a guiding surface for guiding the cable between the cable adjusting screw and the movable member. The guiding surface of the cam member is structured substantially coinciding a portion of a fictitious circle centered at a rotating pin which connects an outer linkage of the parallelogram with a second end of the fixed member. Furthermore, the cable adjusting screw is positioned in such a manner that its extension is always substantially tangential to the guiding surface of the cam member, so as to allow the cable to be pulled in a direction substantially coincident with the axial extension of the cable adjusting screw. <CIT> discloses a derailer for a bicycle, comprising a fitting member, a movable member, and a connecting member for movably connecting the movable member with the fitting member, at least one control member swingable independently of the movable member, a spring energized by the swing of the control member, and a positioning device provided between the control member and one of the fitting member, movable member and connecting member and serving to positionally set a chain guide on the movable member with respect to one of a plurality of sprockets, so that the speed-changing stage previously desired may be selected when the pedals stop rotating regardless of whether the bicycle is at a standstill or coasting. <CIT> discloses a rear derailleur for bicycle gears comprises an upper body which can be fixed to the bicycle frame and a lower body carrying chain transmission member and being movable relative to the upper body to bring the chain into selective engagement with a series of sprockets carried by the hub of the rear wheel of the bicycle. The lower body is connected by an articulated parallelogram joint to an intermediate connecting element which is in turn mounted for sliding on guide member carried by the upper body. Connecting rods are provided for univocally correlating the movements of the intermediate element relative to the upper body with the movements of the lower body relative to the intermediate element.

Accordingly, there is a need for an improved rear derailleur that can move a bicycle chain between gears of a cassette. There is also a need for a rear derailleur that can mitigate the effects of various conditions and hazards that can impact engagement of the bicycle chain and the rear derailleur. There is an additional need for a rear derailleur that is easier to manufacture, assemble, adjust, and maintain. The present invention satisfies these needs and provides other related advantages.

An improved rear derailleur that can move a bicycle chain between gears of a cassette. An improved rear derailleur that can mitigate the effects of various conditions and hazards that can impact engagement of the bicycle chain and the rear derailleur is provided. An improved rear derailleur that is easier to manufacture, assemble, adjust, and maintain is provided.

In an embodiment of the present invention, a rear derailleur assembly for mounting to a bicycle includes an upper body for operationally engaging the rear derailleur assembly to a bicycle frame. A cable stay operationally engages the upper body at a first end and extends away therefrom. The cable stay includes a bore therethrough located at a second end generally opposite the first end. The rear derailleur assembly also includes a chain cage for engaging a chain of the bicycle, and a controller that includes spaced-apart upper and lower link arms. The upper link arm is pivotally connected at one end to the upper body, and the lower link arm is pivotally connected at one end to the upper body. A lower body is operationally connected to the chain cage, with the upper link arm being pivotally connected to the lower body at an end opposite the end pivotally connected to the upper body. The lower link arm is pivotally connected to the lower body at an end opposite the end pivotally connected to the upper body. The upper link arm includes an actuating arm located on an outward facing rear portion of the upper link arm. A spring operationally engages the controller, and biases the upper and lower link arms in a first direction. A cable for actuating the derailleur assembly passes through the bore in the cable stay to operationally engage an end of the actuating arm. Tension on the cable causes relative movement between the upper body and the lower body, moving the upper and lower link arms in a second direction opposite the first direction, and moving the chain cage laterally towards the frame. The second end of the cable stay is generally aligned with the end of the actuating arm when the cable stay is in an operational configuration.

According to an embodiment, the chain cage is pivotally connected to the lower body, rotatable about an axis in first and second directions relative to the lower body, and rotationally biased in the first direction. The lower body includes a one-way bearing operationally engaging the lower body and the chain cage, providing rotation of the chain cage with respect to the one-way bearing in a second direction opposite the first direction. The lower body frictionally engages an exterior of the one-way bearing so that when the chain cage rotates with respect to the lower body in the first direction, the one-way bearing resists rotation as the one-way bearing rotates with the chain cage in the first direction. The cable for actuating the rear derailleur assembly passes through the bore in the cable stay to operationally engage the controller. Tension on the cable causes relative movement between the upper body and the lower body, moving the upper and lower link arms in a second direction opposite the first direction, and moving the chain cage laterally towards the frame.

Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

The various present embodiments now will be discussed in detail with an emphasis on highlighting the advantageous features with reference to the drawings of various embodiments. The illustrated embodiments are intended to illustrate, but not to limit the invention. These drawings include the following figures, in which like numerals indicate like parts:.

The following detailed description describes the present embodiments, with reference to the accompanying drawings. In the drawings, reference numbers label elements of the present embodiments. These reference numbers are reproduced below in connection with the discussion of the corresponding drawing features.

It is to be understood that the figures and descriptions of the present invention have been simplified to illustrate elements that are relevant for a clear understanding of the present invention, while eliminating, for the purpose of clarity, many other elements found in rear derailleurs. Those of ordinary skill in the pertinent arts may recognize that other elements and/or steps are desirable and/or required in implementing the present invention. However, because such elements and steps are well known in the art, and because they do not facilitate a better understanding of the present invention, a discussion of such elements and steps is not provided herein. The disclosure herein is directed to all such variations and modifications to such elements and methods known to those skilled in the pertinent arts.

As shown in <FIG> for purposes of illustration, an embodiment of the present invention resides in a rear derailleur assembly <NUM> engaged to a frame <NUM> of a bicycle (of which only a rear portion of the frame <NUM> is partially shown) near a rear wheel (not shown) of the bicycle. A side of the rear derailleur assembly <NUM> facing the frame <NUM> may be referred to as an inward or inner side while an opposite side of the rear derailleur assembly <NUM> may be referred to as an outward or outer side. The rear derailleur assembly <NUM> is capable of moving a bicycle chain <NUM> laterally between gears (or sprockets or cogs) of a cassette <NUM> connected to the frame <NUM>. The bicycle includes a control cable <NUM> extending between front and rear portions of the bicycle. The control cable <NUM> can be in the form of various cables including, without limitation, a Bowden-type control cable having an outer sheath and an inner wire. One end of the control cable <NUM> is connected to a shift control device (not shown) mounted on or near the bicycle's handlebar (not shown) at the front of the bicycle. The other end of the control cable <NUM> is connected the rear derailleur assembly <NUM>. As outlined above, tension on the control cable <NUM> affects movement of the bicycle chain <NUM> between gears (or sprockets or cogs) of the cassette <NUM> by controlling operation of the rear derailleur assembly <NUM>. [<NUM>]The rear derailleur assembly <NUM> includes an upper body assembly <NUM> that acts as a base member by connecting the rear derailleur assembly <NUM> to a rear drop-out or rear axle holder (not shown) of the bicycle frame <NUM>.

The rear derailleur assembly <NUM> also includes a chain cage assembly <NUM> that engages the bicycle chain <NUM> and moves the bicycle chain <NUM> from one gear of the cassette <NUM> to another gear of the cassette <NUM>.

The rear derailleur assembly <NUM> further includes a controller assembly <NUM> operationally connecting the upper body assembly <NUM> to the chain cage assembly <NUM>. As described in more detail below, movement of the controller assembly <NUM> causes movement of the chain cage assembly <NUM> which, in turn, moves the bicycle chain <NUM> between gears of the cassette <NUM>.

The rear derailleur assembly <NUM> additionally includes a lower body assembly <NUM> that acts as a moveable member operationally connecting the controller assembly <NUM> to the chain cage assembly <NUM>. The lower body assembly <NUM> also operationally connects the upper body assembly <NUM> to the chain cage assembly <NUM> due to the controller assembly <NUM> operationally connecting the upper body assembly <NUM> to the lower body assembly <NUM>.

The upper body assembly <NUM> includes a n upper body portion <NUM>, a mounting bolt (or fixing bolt) <NUM> extending through a bore in the upper body portion <NUM> for threadedly securing the rear derailleur assembly <NUM> to the frame <NUM>, and a folding, spring-loaded cable stay member <NUM> having first and second ends <NUM>, <NUM> generally opposite one another.

The cable stay member <NUM> acts as a support for the control cable <NUM>, and yields under impact in order to avoid breaking or being damaged in the event of crashes or trailside impacts. The cable stay member <NUM> protrudes out and extends away from the upper body portion <NUM> to receive the control cable <NUM> and is vulnerable to impact. The cable stay member <NUM> is pivotally connected to the upper body portion <NUM> at the first end <NUM>. The pivotal connection with the upper body portion <NUM> allows the cable stay member <NUM> to yield under impact if, for example, the right side of the bicycle frame <NUM> impacts the ground during a crash, the bicycle tips over onto its right side and the cable stay member <NUM> contacts a hard surface, or the like. The cable stay member <NUM> is mounted on a pivot pin <NUM> extending through a pair of coaxial apertures <NUM> at the first end <NUM>, anchoring the cable stay <NUM> to the upper body portion <NUM> and allowing the cable stay <NUM> to rotate about a longitudinal axis (or pivot axis) of the pivot pin <NUM>. The cable stay member <NUM> is connected to a spring <NUM> disposed about the pivot pin <NUM>. The spring <NUM> absorbs the force of an impact and mitigates the transference of force to the cable stay member <NUM> that could cause the cable stay member <NUM> to break or break off from the upper body portion <NUM>. The spring-loaded pivotal connection allows the cable stay member <NUM> to move in only one plane. The cable stay member <NUM> remains rigid in the cable pull direction when pull force (i.e., tension) is applied to the control cable <NUM>. A bottom surface (not shown) on the non-hinged side of the first end <NUM> of the cable stay member <NUM> acts as a rotational stop in an outward rotational direction when the bottom surface of the cable stay <NUM> contacts the upper surface of the upper body portion <NUM>. A surface <NUM> of a stop <NUM> on the hinged-side of the first end <NUM> of the cable stay member <NUM> acts as a rotational stop in an inward rotational direction when the surface <NUM> contacts a surface <NUM> of the upper body portion <NUM>. The second end <NUM> of the cable stay <NUM> includes a cable guide bore <NUM> through which the control cable <NUM> passes to be connected to the rear derailleur assembly <NUM>. Openings <NUM>, <NUM> on opposite sides of the cable guide bore <NUM> can be the same size or different sizes, depending on the type of control cable <NUM> used. For example, when the control cable <NUM> is in the form of a Bowden-type control cable having an outer sheath and a n inner wire, the opening <NUM> of the cable guide bore <NUM> on an inward side of the rear derailleur assembly <NUM> receiving the control cable <NUM> may be sized and shaped to receive the outer sheath of the control cable <NUM> (e.g., the diameter of the opening <NUM> of the cable guide bore <NUM> may be larger than or at least large enough for press-fit engagement with the outer surface of the outer sheath of the control cable <NUM>), while the opening <NUM> of the cable guide bore <NUM> on an outward side of the rear derailleur assembly <NUM> from which the control cable <NUM> extends may be sized and shaped to allow only the inner wire of the control cable <NUM> to pass through the opening <NUM>.

The chain cage (or chain guide) assembly <NUM> includes a chain cage that includes a pair of spaced apart, parallel cage plates (also referred to as inner and outer cage plates or inner and outer cage guides) <NUM>, <NUM> with a pair of pulleys (or sprockets or jockey wheels) <NUM>, <NUM> (i.e., an upper guide pulley <NUM> and a lower idler (or tension) pulley <NUM>) disposed therebetween. The plates <NUM>, <NUM> are joined together at an upper end <NUM> by a pivot shaft <NUM>, and joined together at a lower end <NUM> by a pivot shaft <NUM>. The upper guide pulley <NUM> is rotatably mounted on the pivot shaft <NUM> between the plates <NUM>, <NUM>. The lower idler pulley <NUM> is pivotally mounted on the pivot shaft <NUM> between the plates <NUM>, <NUM>. The inner and outer cage plates may be made from various materials including, without limitation, durable coldforged aluminum. The pulleys <NUM>, <NUM> may include sealed precision pulley bearings to reduce friction and avoid contamination.

The lower body assembly <NUM> includes a lower body portion <NUM> operationally connected to the chain cage assembly <NUM>. The bodies of the upper and lower body assemblies <NUM>, <NUM> may be made from various materials including, without limitation, a carbon fiber/nylon composite material; aluminum; plastic or the like.

As stated above, the controller assembly <NUM> operationally connects the chain cage assembly <NUM> to the upper body assembly <NUM>. The controller assembly <NUM> includes a controller including an upper link arm (or upper pivot bar or inner pivot bar) <NUM> and a lower link arm (or lower pivot bar or inner pivot bar) <NUM> spaced apart from one another that acts as a linkage assembly for connecting the upper and lower body assemblies <NUM>, <NUM>. The upper link arm <NUM> is pivotally connected at one end to the upper body portion <NUM> by a pivot pin <NUM> (the pivot pin <NUM> passing through coaxial apertures in the upper link arm <NUM> and the upper body portion <NUM>). The lower link arm <NUM> is pivotally connected at one end to the upper body portion <NUM> by a pair of spaced apart, coaxial pivot pins <NUM>, <NUM> to form a split or two part pivot where the lower link arm <NUM> pivotally engages the upper body portion <NUM> (the pivot pins <NUM>, <NUM> passing through respective coaxial apertures in the lower link arm <NUM> and the upper body portion <NUM>), and allowing space <NUM> between the two coaxial pivot pins <NUM>, <NUM>. The upper and lower body portions <NUM>, <NUM> are part of the controller assembly <NUM>. The upper link arm <NUM> is pivotally connected to the lower body portion <NUM> by a pivot pin <NUM> (the pivot pin <NUM> passing through coaxial apertures in the upper link arm <NUM> and the lower body portion <NUM>) at an end opposite the end pivotal ly connected to the upper body portion <NUM>. The lower link arm <NUM> is pivotally connected to the lower body portion <NUM> by a pivot pin <NUM> (the pivot pin <NUM> passing through coaxial apertures in the lower link arm <NUM> and the lower body portion <NUM>) at an end opposite the end pivotally connected to the upper body portion <NUM>. The upper link arm <NUM> includes an actuating arm <NUM> extending downwardly from the upper link arm <NUM> through an aperture <NUM> of the lower link arm <NUM>. The actuating arm <NUM> is generally located on an outward facing rear portion of the upper link arm <NUM>. In one particular embodiment, the actuating arm <NUM> extends downwardly from the aperture (not shown) on the rear, outward portion of the upper link arm <NUM> through which the pivot pin <NUM> passes to engage the rear, outward portion of the upper link arm <NUM>. The control cable <NUM> is secured to the actuating arm <NUM> by a cable anchor bolt (or cable clamp) <NUM> engaging the actuating arm <NUM>.

The controller assembly <NUM> includes a spring <NUM> (sometimes referred to as a return spring) operationally engaging the controller (i.e., the upper and lower link arms <NUM>, <NUM>). The spring <NUM> is operationally connected at one end about the pivot pin <NUM> and at the other end about the pivot pin <NUM> to normally bias the upper and lower link arms <NUM>, <NUM> in a first direction such that the lower body portion <NUM> is normally biased outwardly away from the bicycle frame <NUM> relative to the upper body portion <NUM> engaging the bicycle frame <NUM>. In operation, the upper a nd lower link arms <NUM>, <NUM> generally form a parallelogram with the upper and lower body portions <NUM>, <NUM>; the parallelogram rotating about the pivot pins <NUM>, <NUM>, <NUM>, <NUM>, <NUM> as the spring <NUM> expands and contracts between strained and unstrained configurations. As the spring <NUM> is strained and expands, the parallelogram rotates about the pivot pins <NUM>, <NUM>, <NUM>, <NUM>, <NUM> which, in turn, rotates the actuating arm <NUM> of the upper link arm <NUM> towards the split pivot <NUM>, <NUM> and passes into a space <NUM> between the pivots <NUM>, <NUM>. The spring <NUM> biases the chain cage assembly <NUM> to an innermost or outermost position relative to the gears of the cassette <NUM>. The arrangement of the actuating arm <NUM> and the split pivot provides a more compact design for the rear derailleur assembly <NUM>. A high limit screw (or outer limit screw) <NUM> and a low adjustment screw (or lower limit screw) <NUM> are used to adjust the range the parallelogram rotates about the pivot pins <NUM>, <NUM>, <NUM>, <NUM>, <NUM> so that chain cage assembly <NUM> be positioned over no more than the highest gear and no less than the lowest gear. Turning the limit screws <NUM>, <NUM> adjusts the limit of travel of the pulleys <NUM>, <NUM>. Tightening the limit screws <NUM>, <NUM> restricts the travel, while loosening the limit screws <NUM>, <NUM> allows more travel. The purpose of the adjusting the limit screws <NUM>, <NUM> is to find the tightest high limit screw setting that will allow a good shift to the outermost gear (i.e., the smallest in size) on the cassette <NUM>, and the tightest lower limit screw setting that will allow a good shift to the innermost gear (i.e., the largest in size) on the cassette <NUM>. The high limit screw <NUM> is used to adjust the rear derailleur assembly <NUM> such that the upper pulley <NUM> is centered with the center of the highest gear. An angle adjustment screw (or B- adjustment screw) <NUM> is used to adjust the rear derailleur assembly <NUM> such that there are <NUM>- <NUM> in-between the top of the upper pulley <NUM> and the bottom of the lowest gear on the cassette <NUM>.

In use, the control cable <NUM> for actuating the rear derailleur assembly <NUM> passes through the cable bore <NUM> in the cable stay <NUM> to operationally engage an end <NUM> of the actuating arm <NUM>. Tension on the control cable <NUM> causes relative movement between the upper body portion <NUM> and the lower body portion <NUM>, moving the upper and lower link arms <NUM>, <NUM> in a second direction opposite the first direction where the lower body portion <NUM> and the chain cage assembly <NUM> are normally biased outwardly away from the bicycle frame <NUM>, and moving the lower body portion <NUM> and the chain cage assembly <NUM> laterally towards the bicycle frame <NUM>. As stated above, the amount of tension on the control cable <NUM> determines which direction the bicycle chain <NUM> will move in (i.e., from lower gear to higher gear or from higher gear to lower gear). The shift control device (not shown) allows the rider of the bicycle to pull (increase tension) or release (decrease tension) the control cable <NUM>. With the control cable <NUM> (e.g., an inner wire if the control cable <NUM> is a Bowden-type cable), the chain cage assembly <NUM> can be moved laterally by moving the controller assembly <NUM> via the amount of tension on the inner wire. One end of the inner wire is connected the actuating arm <NUM> by the cable anchor bolt <NUM>, and the other end of the inner wire is connected to the shift control device mounted on the bicycle handlebar. When the shift control device is operated by the rider, tension on the inner wire of the control cable is pulled or released. Pulling the inner wire (i.e., increasing tension on the inner wire) of the control cable <NUM> moves the chain cage assembly <NUM> against the biasing force of the spring <NUM>, while releasing the inner wire (i.e., decreasing tension on the inner wire) causes the chain cage assembly <NUM> to move due to the biasing force of the spring. Increasing tension on the control cable <NUM> causes the chain cage assembly <NUM> to move in one direction (which, in turn, moves the bicycle chain <NUM> in that same direction), while releasing tension on the control cable <NUM> causes the chain cage assembly <NUM> to move in another direction (generally the opposite direction the chain cage assembly <NUM> moves in when tension is increased). Thus, the chain cage assembly <NUM> (along with the bicycle chain <NUM>) can be moved laterally by increasing or decreasing tension on the control cable <NUM>. When the control cable <NUM> is pulled (i.e., tension increased), the upper and lower link arms <NUM>, <NUM> pivot inwardly against the force of the spring <NUM> so as to move the chain cage assembly <NUM> inwardly towards the bicycle which, in turn, moves the bicycle chain <NUM> from one gear to another on the cassette <NUM>. When the control cable <NUM> is released (i.e., tension decreased), the upper and lower link arms <NUM>, <NUM> pivot outwardly, pulled by the force of the spring <NUM>, so as to move the chain cage assembly <NUM> outwardly away from the bicycle which, in turn, moves the bicycle chain <NUM> from one gear to another on the cassette <NUM>.

As stated above, the lower body portion <NUM> is operationally connected to the chain cage assembly <NUM>. The lower body portion <NUM> includes an oversized front top pivot <NUM> where the pivot pin <NUM> pivotally engages the upper link arm <NUM> with the lower body portion <NUM>. The front top pivot <NUM> provides stiffness and a cantilevered stationary pin <NUM> with a head mounted to the front knuckle <NUM>, providing a design that also minimizes the dimension the rear derailleur assembly <NUM> protrudes outwardly away from the bicycle.

The lower body portion <NUM> is rotatably secured to the cage plate <NUM> closest to lower body portion <NUM>, with the entire cage assembly <NUM> having limited rotation about a pivot axis <NUM> relative to the lower body portion <NUM>, as illustrated by arrow <NUM>. As discussed in more detail below, the chain cage assembly <NUM> is spring-loaded about the pivot axis <NUM> in one direction of rotation, and there is a limited range of rotation between the chain cage assembly <NUM> and the lower body portion <NUM>.

There is a one-way damping assembly (or damping arrangement) <NUM> for pivotal movement of the chain cage assembly <NUM> that creates friction to slow or reduce rotation speed of the chain cage around the pivot axis <NUM> in an opposite direction of rotation from the direction of rotation provided by the force of the spring-load. The one-way damping arrangement provides increased tension as the chain cage assembly <NUM> moves forward and releases tension as the chain cage assembly <NUM> travels back. I n the direction of rotation provided by the spring-load, the damping arrangement creates no friction. The damping arrangement is located in a knuckle <NUM> of the lower body portion. The knuckle includes a generally cylindrical bore <NUM>. A spring <NUM> (e.g., a torsion spring) is loaded to bias the chain cage assembly <NUM> in one direction. A stop <NUM> extending outward from the plate <NUM> prevents the chain cage assembly <NUM> from rotating past a certain point in the direction of rotational bias imparted by the spring <NUM> when the stop <NUM> engages the lower body portion <NUM>, preventing further rotational movement of the chain cage assembly <NUM> relative to the lower body portion <NUM>. The spring <NUM> biases the chain cage assembly <NUM> in a chain tensioning direction around a central shaft (or central axle) <NUM> operationally engaging the chain cage assembly <NUM> coaxial with the front knuckle bore <NUM> and passing through a one-way bearing <NUM>. A bolt <NUM> extends through an aperture <NUM> in the plate <NUM> to engage the central shaft <NUM>, securing a pivot base <NUM> between the shaft <NUM> and the plate <NUM>, and a seal <NUM> between the lower body portion <NUM> and the plate <NUM>. The spring <NUM> operationally engages the central shaft <NUM> so that torsional force is transmitted to the central shaft <NUM> from the spring <NUM>. The central shaft <NUM> is housed in the bore <NUM> of the lower body portion <NUM> so that the chain cage assembly <NUM> can apply a sufficient tension to the bicycle chain <NUM>. The one-way bearing <NUM> is press-fit into the knuckle bore <NUM> for a friction fit. The central shaft <NUM> moves with the chain cage assembly <NUM> and when rotating in one direction engages with the one-way bearing <NUM>. The one-way bearing <NUM> is held in a press/friction fit within the knuckle bore <NUM> so friction is produced as the one-way bearing <NUM> turns with the central shaft <NUM> and the chain cage assembly <NUM>, producing the dampened movement of the chain cage assembly <NUM> to reduce unwanted movement of the bicycle chain <NUM>. Various other minor components serve the purpose of interconnecting the identified major components of the dampening arrangement. A cap <NUM> engages the lower body portion <NUM> and covers the opening to the bore <NUM>. As illustrated, three fasteners <NUM> pass through spaced-apart apertures <NUM> of the cap <NUM>, and enter spaced- apart apertures <NUM> of the lower body portion <NUM> (the apertures <NUM> of the cap <NUM> being aligned with the apertures <NUM> of the lower body portion <NUM>) to securably fasten the cap <NUM> to the lower body portion <NUM> and enclose the damping assembly <NUM>. An advantage of this damping assembly <NUM> as compared to others is that this damping assembly <NUM> uses fewer parts and requires no additional friction-producing elements to be aligned or fixed in place. The damping assembly <NUM> is also lightweight and simple for manufacturing.

In addition, the claimed invention is not limited in size and may be constructed in various sizes in which the same or similar principles of operation as described above would apply. Furthermore, the figures (and various components shown therein) of the specification are not to be construed as drawn to scale.

The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.

I n contrast, when an element is referred to as being "directly on," "directly engaged to", "directly connected to" or "directly coupled to" another element or layer, there may be no intervening elements or layers present.

Spatially relative terms, such as "front," "rear," "left," "right," "inner," "outer," "beneath", "below", "lower", "above", "upper", "horizontal", "vertical", "lateral", "longitudinal" and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures.

Claim 1:
A rear derailleur assembly (<NUM>) for mounting to a bicycle, wherein the bicycle includes a frame (<NUM>) and a cable for actuating the rear derailleur assembly (<NUM>), comprising:
an upper body (<NUM>) for operationally engaging the rear derailleur assembly (<NUM>) to the frame (<NUM>);
a cable stay (<NUM>) operationally engaging the upper body (<NUM>) at a first end and extending away therefrom, wherein the cable stay (<NUM>) includes a bore (<NUM>) therethrough located at a second end generally opposite the first end;
a chain cage (<NUM>) for engaging a chain (<NUM>) of the bicycle;
a controller (<NUM>) comprising spaced-apart upper and lower link arms (<NUM>, <NUM>), the upper link arm (<NUM>) being pivotally connected at one end to the upper body (<NUM>), and the lower link (<NUM>) arm being pivotally connected at one end to the upper body (<NUM>);
a lower body (<NUM>) operationally connected to the chain cage (<NUM>), the upper link arm (<NUM>) being pivotally connected to the lower body (<NUM>) at an end opposite the end pivotally connected to the upper body (<NUM>), and the lower link arm (<NUM>) being pivotally connected to the lower body (<NUM>) at an end opposite the end pivotally connected to the upper body (<NUM>), a spring (<NUM>) operationally engaging the controller, and biasing the upper and lower link arms (<NUM>, <NUM>) in a first direction;
characterized in that
the upper link arm (<NUM>) includes an actuating arm (<NUM>) located on an outward facing rear portion of the upper link arm (<NUM>),
the cable for actuating the derailleur assembly (<NUM>) passes through the bore (<NUM>) in the cable stay (<NUM>) to operationally engage an end of the actuating arm (<NUM>), whereby tension on the cable causes relative movement between the upper body (<NUM>) and the lower body (<NUM>), moves the upper and lower link arms (<NUM>, <NUM>) in a second direction opposite the first direction, and
moves the chain cage (<NUM>) laterally towards the frame (<NUM>), wherein the second end of the cable stay (<NUM>) is generally aligned with the end of the actuating arm (<NUM>) when the cable stay (<NUM>) is in an operational configuration.