Patent Description:
Some modern bicycles have hydraulic disk brakes. In order for these brakes to function properly the brake pads must be changed once they are worn beyond a certain point. The brake pads (also referred to as brake pad assemblies when the brake pads are combined with other elements in a unitary package) are positioned within a brake caliper body. In order to exchange the old brake pads for new ones a disk brake may require pushing back the brake pistons within the brake caliper body in order to make room for installation of replacement pads. Current tools and methods typically require removal of the wheel from the bicycle and/or removal of the brake caliper body from the bicycle. Not only are current tools and methods time intensive, inaccurate, and/or cause piston damage, they also often require realignment of the entire brake system following brake pad replacement, which can further add to brake maintenance costs. A caliper piston tool according to the preamble of claim <NUM> is known from <CIT>.

Implementations described and claimed herein address the foregoing problems by providing a caliper piston tool comprising a first handle including a guide track and a first paddle fixed in position on the first handle, a second handle to pivot about the first handle at a handle joint, the second handle including a drive finger fixed in position on the second handle, and a second paddle. The second paddle includes a drive socket, wherein the drive finger is engaged within the drive socket, and a guide follower constrained to linear motion along the guide track, wherein rotation of the drive finger about the handle joint drives a linear motion of the guide follower along the guide track.

Implementations described and claimed herein address the foregoing problems by further providing a method of using a caliper piston tool comprising inserting a first paddle and a second paddle between a pair of opposing caliper pistons, the first paddle fixed in position on a first handle, the first handle including a guide track; and compressing the first handle and a second handle together, the second handle to pivot about the first handle at a handle joint, and the second handle including a drive finger fixed in position on the second handle. The second paddle includes a drive socket, wherein the drive finger is engaged within the drive socket, and a guide follower constrained to linear motion along the guide track, wherein rotation of the drive finger about the handle joint drives a linear motion of the guide follower along the guide track and separation of the first paddle and the second paddle in response to the compressing operation.

The presently disclosed technology allows brake pads to be replaced without dismantling a bicycle, resulting in significant time and cost savings as well as convenience for do-it-yourself and professional mechanics alike. While the description herein is directed explicitly to disk brakes for bicycles, the caliper piston tool may also be used on disk brakes for other vehicles (e.g., motorcycles, scooters, automobiles, all-terrain vehicles (ATVs), side-by-sides (SxS), and electric mobility vehicles).

<FIG> illustrates a first perspective view of an example caliper piston tool <NUM>. <FIG> illustrates a second perspective view of the example caliper piston tool <NUM> of <FIG>. The tool <NUM> includes a first handle <NUM> (which, in turn, includes a first paddle <NUM>), a second handle <NUM>, and a second paddle <NUM>. The first handle <NUM> includes a first handle grip <NUM> extending in a first general direction away from a handle joint <NUM>. The first handle grip <NUM> may function as a first lever arm for a user to operate the tool <NUM>.

The first handle <NUM> further includes a first paddle <NUM> that extends in a second general direction away from the handle joint <NUM>. The first paddle <NUM> forms a flush front face of the tool <NUM>, as shown in <FIG>. In other implementations, another portion of the first handle <NUM> or other component of the tool <NUM> extends beyond the first paddle <NUM> at the depicted front of the tool <NUM> illustrated in <FIG>. The first paddle <NUM> is a thin, rigid, and generally flat structure that may in conjunction with a second paddle <NUM>, which is also a thin, rigid, and generally flat structure be wedged between a pair of brake pads to mechanically separate the brake pads for inspection, removable, and/or replacement. The paddles <NUM>, <NUM> each includes chamfered leading edges <NUM>, <NUM>, respectively, that aid a user in inserting the paddles <NUM>, <NUM> between the pair of brake pads. The first handle <NUM> still further includes a guide track <NUM> that serves to constrain motion of the second paddle <NUM> to linear motion along the guide track <NUM>. The second paddle <NUM> includes a guide follower <NUM> that fits within, onto, and/or over the guide track <NUM>, and serves to define the linear motion along the guide track <NUM>.

The second handle <NUM> includes a second handle grip <NUM> extending in a third general direction away from the handle joint <NUM>. The second handle grip <NUM> may function as a second lever arm for the user to operate the tool <NUM>. Specifically, the user may compress the handle grips <NUM>, <NUM> together to drive the paddle <NUM>, <NUM> apart. Similarly, the user may separate the handle grips <NUM>, <NUM> together to bring the paddles <NUM>, <NUM> together. The handle grips <NUM>, <NUM> may each include a rubberized coating, knurling, or other texture to enhance the user's comfort and level of grip applied to the handle grips <NUM>, <NUM>. Further, the handle grips <NUM>, <NUM> can be fitted with molded grips, sprayed or dipped with a non-slip or texturized coating, or left bare to be used with gloves.

The handle joint <NUM> constrains motion of the second handle <NUM> with reference to the first handle <NUM> to rotation about the handle joint <NUM>. Each of the handles <NUM>, <NUM> include an aperture (not shown) that are aligned. A mechanical fastener <NUM> (e.g., a rivet, cotter pin/cotter bolt, screw / threaded aperture, bolt / bushing / nut) having a shaft extends through the apertures. The mechanical fastener shaft and apertures form a plain bearing at the handle joint <NUM>. Other implementations may include other types of bearings at the handle joint <NUM>.

Here, the first handle <NUM> is a split structure at the handle joint <NUM> and the guide track <NUM> to accommodate the second handle <NUM> within a receiving slot <NUM> formed by the split first handle <NUM>. This serves to further secure the second handle <NUM> to the first handle <NUM> and limit the movement of the second handle <NUM> with reference to the first handle <NUM> to rotation about the handle joint <NUM>. Other implementations of the first handle <NUM> may not include the split structure or the receiving slot <NUM> and rotation of the second handle <NUM> with reference to the first handle <NUM> may be constrained merely by the handle joint <NUM> (or other features of the tool <NUM>).

The second handle <NUM> further includes a drive finger (not shown, see e.g., drive finger <NUM> of <FIG>) extending in a fourth general direction away from the handle joint <NUM> and oriented within the receiving slot <NUM>. The drive finger engages a drive socket (also not shown, see e.g., drive socket <NUM> of <FIG>) in the guide follower <NUM> on the second paddle <NUM>. This permits rotation of the second handle grip <NUM> about the handle joint <NUM> to drive a similar rotation of the drive finger. The rotation of the drive finger drives a linear motion of the drive socket in the guide follower <NUM> along the guide track <NUM>, which yields a similar linear motion of the second paddle <NUM> with reference to the first paddle <NUM>. In other implementations, the drive finger / drive socket is visible on the outside of the tool <NUM>. Further, a pair of drive fingers / drive sockets may be located on both sides of the tool <NUM>.

The guide track <NUM> is a v-shaped depression in the first handle <NUM> running parallel with a desired linear motion of the second paddle <NUM> with reference to the first paddle <NUM>. The guide follower <NUM> is a similarly v-shaped protrusion in the second paddle <NUM> that fits in the guide track <NUM>. A result is that movement of the second paddle <NUM> with reference to the first paddle <NUM> is limited to a single linear direction running parallel with the v-shaped depression in the first handle <NUM> and the v-shaped protrusion in the second paddle <NUM>. Other shapes and orientations of the guide track / guide follower are contemplated herein that limit movement of the second paddle <NUM> with reference to the first paddle <NUM> to a single linear direction. For example, the guide track / guide follower can be any corresponding combination of matching shapes that are constrained to movement in a singular linear direction. More specifically, the guide track may be an aperture and the guide follower may be a protrusion of a similar slightly smaller shape (e.g., matching circular, square, star or hexagon cross-sectional shapes).

In various implementations, the first handle grip <NUM>, the first paddle <NUM>, the guide track <NUM>, and the receiving slot <NUM> are all features of the first handle <NUM> that are all structurally contiguous and fixed in position on the first handle <NUM>. Similarly, the second handle grip <NUM> and the drive finger are both features of the second handle <NUM> that are structurally contiguous and fixed in position on the second handle <NUM>. Similarly, the guide follower <NUM> and the drive socket are structurally contiguous and fixed in position on the second paddle <NUM>.

In various implementations, the first handle <NUM>, the second handle <NUM>, and the second paddle <NUM> may each be made of various metal alloys and/or durable hard plastics, for example. Further, the components of the tool <NUM> that come in direct contact with brake system components are the paddles <NUM>, <NUM>. These components may be specially coated, for example with rubber, or chrome finished in order to protect the brake components that they come in contact with.

<FIG> illustrates a first perspective exploded view of an example caliper piston tool <NUM>. <FIG> illustrates a second perspective exploded view of the example caliper piston tool <NUM> of <FIG>. The tool <NUM> includes a first handle <NUM> (which, in turn, includes a first paddle <NUM>), a second handle <NUM>, and a second paddle <NUM>. The first handle <NUM> includes a first handle grip <NUM> extending in a first general direction away from a handle joint <NUM>.

The first handle <NUM> further includes a first paddle <NUM> that extends in a second general direction away from the handle joint <NUM>. The first handle <NUM> still further includes a guide track <NUM> that serves to constrain motion of the second paddle <NUM> to linear motion along the guide track <NUM>. The second paddle <NUM> includes a guide follower <NUM> that fits within, onto, and/or over the guide track <NUM>, and serves to define the linear motion along the guide track <NUM>.

The second handle <NUM> includes a second handle grip <NUM> extending in a third general direction away from the handle joint <NUM>. The handle joint <NUM> constrains motion of the second handle <NUM> with reference to the first handle <NUM> to rotation about the handle joint <NUM>. The handles <NUM>, <NUM> include apertures <NUM>, <NUM>, respectively, that are aligned and a mechanical fastener (here, bolt <NUM> and nut <NUM>) extends therethrough. This forms a plain bearing at the handle joint <NUM>. Other implementations may include other types of mechanical fasteners and bearings at the handle joint <NUM>.

Here, the first handle <NUM> is a split structure at the handle joint <NUM> and the guide track <NUM> to accommodate the second handle <NUM> within a receiving slot <NUM> formed by the split first handle <NUM>. This serves to further secure the second handle <NUM> to the first handle <NUM> and limit the movement of the second handle <NUM> with reference to the first handle <NUM> to rotation about the handle joint <NUM>. Other implementations of the first handle <NUM> may not include a split structure or the receiving slot <NUM> and rotation of the second handle <NUM> with reference to the first handle <NUM> may be constrained merely by the handle joint <NUM> (or other features of the tool <NUM>).

The second handle <NUM> further includes a drive finger <NUM> extending in a fourth general direction away from the handle joint <NUM> and oriented within the receiving slot <NUM>. The drive finger <NUM> engages a drive socket <NUM> in the guide follower <NUM> on the second paddle <NUM>. This permits rotation of the second handle grip <NUM> about the handle joint <NUM> to drive a similar rotation of the drive finger <NUM>. The rotation of the drive finger <NUM> drives a linear motion of the drive socket <NUM> in the guide follower <NUM> along the guide track <NUM>, which yields a similar linear motion of the second paddle <NUM> with reference to the first paddle <NUM>.

The guide track <NUM> is a v-shaped depression in the first handle <NUM> running parallel with a desired linear motion of the second paddle <NUM> with reference to the first paddle <NUM>. The guide follower <NUM> is a similarly v-shaped protrusion in the second paddle <NUM> that fits in the guide track <NUM>. A result is that movement of the second paddle <NUM> with reference to the first paddle <NUM> is limited to a single linear direction running parallel with the v-shaped depression in the first handle <NUM> and the v-shaped protrusion in the second paddle <NUM>. Other shapes and orientations of the guide track / guide follower are contemplated herein that limit movement of the second paddle <NUM> with reference to the first paddle <NUM> to a single linear direction.

The second handle <NUM> further includes a handle stop <NUM> that limits compression of the handle grips <NUM>, <NUM>, thus limiting a distance that the user may drive the paddles <NUM>, <NUM> apart. More specifically, the handle stop <NUM> comes in contact with the first handle <NUM> when the user brings the handle grips <NUM>, <NUM> together, preventing the handle grips <NUM>, <NUM> from being further compressed together. While the handle stop <NUM> is oriented on the second handle <NUM> in <FIG>, in other implementations, the handle stop <NUM> may be oriented in a similar position on the first handle <NUM> or there may be matching handle stops on each of the handles <NUM>, <NUM>. Further, the handle stop <NUM> may be adjustable in position or size to vary the distance that the user may drive the paddles <NUM>, <NUM> apart to achieve a predetermined desired separation distance of the paddles <NUM>, <NUM>. For example, the location and/or size of the handle stop <NUM> may be adjusted to either increase or decrease the spreadable range of the paddles <NUM>, <NUM>, depending in part on what size of brake system the caliper piston tool <NUM> is being used on. In other implementations, the handle stop <NUM> is or includes a biasing element (e.g., a spring) that biases the handle grips <NUM>, <NUM> open or closed.

The tool <NUM> also includes a friction adjuster that is made up of a track aperture <NUM>, a follower aperture <NUM>, and a friction fastener <NUM>. The friction fastener <NUM> extends through aligned apertures <NUM>, <NUM> and is used to adjust a tolerance between the guide track <NUM> and the guide follower <NUM>. The tolerance defines the ease at which the handle grips <NUM>, <NUM> are moved by a user, and whether the handle grips <NUM>, <NUM> are capable of moving on their own by force of gravity (e.g., by falling open or closed). In the implementation of <FIG>, the track aperture <NUM> is slotted to allow for the friction fastener <NUM> to be selectively positioned within the track aperture <NUM>. Further, the follower aperture <NUM> is threaded to permit the friction fastener <NUM> to screw into the follower aperture <NUM>. The follower aperture <NUM> may include a thread-locking mechanism or substance to hold the friction fastener <NUM> in place and not inadvertently screwing in or out of the follower aperture <NUM>. Other implementations may utilize a bolt / nut combination rather than the threaded follower aperture <NUM> in a similar fashion.

In various implementations, the first handle grip <NUM>, the first paddle <NUM>, the guide track <NUM>, track aperture <NUM>, and the receiving slot <NUM> are all features of the first handle <NUM> that are all structurally contiguous and fixed in position on the first handle <NUM>, as shown in <FIG>. Similarly, the second handle grip <NUM>, the drive finger <NUM>, and the handle stop <NUM> are all features of the second handle <NUM> that are all structurally contiguous and fixed in position on the second handle <NUM>, as shown in <FIG>. Similarly, the guide follower <NUM>, follower aperture <NUM>, and the drive socket <NUM> are structurally contiguous and fixed in position on the second paddle <NUM>, as shown in <FIG>.

<FIG> illustrates a cross sectional view of an example caliper piston tool <NUM> in an open position. The tool <NUM> includes a first handle <NUM> (which, in turn, includes a first paddle <NUM>), a second handle <NUM>, and a second paddle <NUM>. The first handle <NUM> includes a first handle grip <NUM> extending in a first general direction away from a handle joint <NUM>. The first handle <NUM> further includes the first paddle <NUM> that extends in a second general direction away from the handle joint <NUM>. The first handle <NUM> still further includes a guide track (not shown) that serves to constrain motion of the second paddle <NUM> to linear motion along the guide track. The second paddle <NUM> includes a guide follower (not shown) that fits within, onto, and/or over the guide track, and serves to define the linear motion along the guide track.

The second handle <NUM> includes a second handle grip <NUM> extending in a third general direction away from the handle joint <NUM>. The handle joint <NUM> constrains motion of the second handle <NUM> with reference to the first handle <NUM> to rotation about the handle joint <NUM>. The second handle <NUM> further includes a drive finger <NUM> extending in a fourth general direction away from the handle joint <NUM> and oriented within a receiving slot (not shown) of the tool <NUM>. The drive finger <NUM> engages a drive socket <NUM> in the guide follower on the second paddle <NUM>. This permits rotation of the second handle grip <NUM> about the handle joint <NUM> to drive a similar rotation of the drive finger <NUM>. The rotation of the drive finger <NUM> drives a linear motion of the drive socket <NUM> in the guide follower along the guide track, which yields a similar linear motion of the second paddle <NUM> with reference to the first paddle <NUM>.

To achieve the depicted open position, a user may manipulate the second handle grip <NUM> towards the first handle grip <NUM>, which will cause rotation of the second handle <NUM> about the handle joint <NUM> and the drive finger <NUM>, affixed to the second handle <NUM>, to rotate down and forward inside the drive socket <NUM>. This causes the guide follower to move backwards or proximally toward the handle side of the caliper piston tool <NUM> and the second paddle <NUM> that is affixed to the guide follower to move away from the first paddle <NUM>. Generally, the closer the handle grips <NUM>, <NUM> are to one another, the farther the paddles <NUM>, <NUM> will be from one another. Conversely, the further the handle grips <NUM>, <NUM> are from one another, the closer the paddles <NUM>, <NUM> will be to one another.

In various implementations, the paddles <NUM>, <NUM> each include an <NUM> x <NUM> flat area and are each <NUM> thick. Further, an opening A between the paddles <NUM>, <NUM> when the tool <NUM> is in the open position of <FIG> may be limited to <NUM>. Further, the handle grips <NUM>, <NUM> may each be <NUM> - <NUM> long. A distance from a proximal end of the handle grips <NUM>, <NUM> to a front face of the tool <NUM> may be <NUM>, and the first paddle <NUM> may be flush with the front face of the tool <NUM>, or inset <NUM> from the front face of the tool <NUM>. Dimensions provided for the tool <NUM> are examples only, other dimensions are contemplated herein. Further, all dimensions provided for the tool <NUM> are approximate. Approximately within the meaning of the present application is +/- <NUM>% of the given dimension.

<FIG> illustrates a cross sectional view of an example caliper piston tool <NUM> in a closed position. The tool <NUM> includes a first handle <NUM> (which, in turn, includes a first paddle <NUM>), a second handle <NUM>, and a second paddle <NUM>. The first handle <NUM> includes a first handle grip <NUM> extending in a first general direction away from a handle joint <NUM>. The first handle <NUM> further includes the first paddle <NUM> that extends in a second general direction away from the handle joint <NUM>. The first handle <NUM> still further includes a guide track (not shown) that serves to constrain motion of the second paddle <NUM> to linear motion along the guide track. The second paddle <NUM> includes a guide follower (not shown) that fits within, onto, and/or over the guide track, and serves to define the linear motion along the guide track.

To achieve the depicted closed position, the second handle grip <NUM> is moved away from the first handle grip <NUM> (e.g., by action of gravity, inward pressure on the paddles <NUM>, <NUM> from the brake pistons, separation force caused by a user, or a springloaded mechanism with the tool <NUM>), the drive finger <NUM> rotates up and backward within the drive socket <NUM> causing the guide follower and the second paddle <NUM> fixed to it to move forward or distally away from the handle side of the caliper piston tool <NUM> and towards the first paddle <NUM> on a distal side of the tool <NUM>. Generally, the closer the handle grips <NUM>, <NUM> are to one another, the farther the paddles <NUM>, <NUM> will be from one another. Conversely, the further the handle grips <NUM>, <NUM> are from one another, the closer the paddles <NUM>, <NUM> will be to one another.

<FIG> is a flowchart of example operations <NUM> for using a caliper piston tool. In an adjusting operation <NUM>, a user adjusts a friction adjuster to mechanically set a tolerance between a guide track and a guide follower of the caliper piston tool. The tolerance between the guide track and the guide follower defines a resistance of the caliper piston tool to change state between an open position (as illustrated in <FIG>) and a closed position (as illustrated in <FIG>). In a removal operation <NUM>, the user removes one or more brake pads from a brake caliper body. The brake caliper body is associated with a disc brake assembly for a vehicle, such as a bicycle, automobile, motorcycle, scooter, all-terrain vehicle (ATV), side-by-side (SxS), and electric mobility vehicle.

In an inserting operation <NUM>, the user inserts a first paddle and a second paddle of the caliper piston tool between a pair of opposing caliper pistons within the brake caliper body. In various implementations, the first paddle is fixed in position on a first handle of the caliper piston tool and the first handle includes the guide track as well. In an example implementation where the brake caliper body is still installed on a brake rotor and when the inserting operation <NUM> is performed, the first paddle is inserted between a first brake piston within the brake caliper body and a first side of a brake rotor and the second paddle is inserted between a second brake piston within the brake caliper body and a second side of the brake rotor. In various implementations, the inserting operation <NUM> may be accomplished with or without removing a corresponding wheel and tire from the vehicle, with or without removing the brake caliper body from the brake rotor, and with or without corresponding brake pads remaining in place on the opposing caliper pistons.

In a compressing operation <NUM>, the user compresses the first handle and a second handle of the caliper piston tool together. The compressing operation <NUM> causes the second handle to pivot about the first handle at a handle joint. The second handle includes a drive finger fixed in position on the second handle. The second paddle includes a drive socket and the drive finger is engaged within the drive socket. The guide follower is constrained to linear motion along the guide track, as rotation of the drive finger about the handle joint drives a linear motion of the guide follower along the guide track and separation of the first paddle and the second paddle in response to the compressing operation <NUM>. In various implementations, the compressing operation <NUM> re-positions the caliper piston tool from the closed position (as illustrated in <FIG>) to the open position (as illustrated in <FIG>).

In various implementations, the first handle further includes a first handle grip and the second handle further includes a second handle grip and to execute the compressing operation <NUM>, the user squeezes the first and second handle grips together to induce rotation of the second handle about the first handle. Further, the compressing operation <NUM> may push the first piston within the brake caliper body away from the first side of the brake rotor and the second piston within the brake caliper body away from the second side of the brake rotor. The compressing operation <NUM> may uniformly apply outward pressure on the pistons thus moving the pistons to a position sitting flush with interior walls within the brake caliper body.

In a releasing operation <NUM>, the user releases the second handle from the first handle. A biasing force, gravity, or user manipulation of the first and second handle grips may cause an opposite rotation of the second handle about the first handle. This drives a corresponding opposite rotation of the drive finger about the handle joint to drive an opposite linear motion of the guide follower along the guide track, thus moving the first paddle and the second paddle back together. In various implementations, the compressing operation <NUM> re-positions the caliper piston tool from the open position (as illustrated in <FIG>) to the closed position (as illustrated in <FIG>).

In a removing operation <NUM>, the user removes the first paddle and the second paddle from between the opposing caliper pistons within the brake caliper body. In an inserting operation <NUM>, the user places one or more replacement brake pads within the brake caliper body. In a resetting operation <NUM>, the user resets the replacement brake pad locations relative to the first and second sides of the brake rotor by pumping on a brake system actuator for the vehicle.

The logical operations making up the embodiments of the invention described herein may be referred to variously as operations, steps, objects, or modules. Furthermore, it should be understood that logical operations may be performed in any order, adding or omitting operations as desired, unless explicitly claimed otherwise or a specific order is inherently necessitated by the claim language.

Claim 1:
A caliper piston tool (<NUM>, <NUM>, <NUM>, <NUM>) comprising:
a first handle (<NUM>, <NUM>, <NUM>, <NUM>) including a guide track (<NUM>, <NUM>) and a first paddle (<NUM>, <NUM>, <NUM>, <NUM>) fixed in position on the first handle;
a second handle (<NUM>, <NUM>, <NUM>, <NUM>) to pivot about the first handle at a handle joint (<NUM>, <NUM>, <NUM>, <NUM>), the second handle including a drive finger (<NUM>, <NUM>, <NUM>) fixed in position on the second handle; and
a second paddle (<NUM>, <NUM>, <NUM>, <NUM>) characterised in that the second paddle includes:
a drive socket (<NUM>, <NUM>, <NUM>), wherein the drive finger is engaged within the drive socket, and
a guide follower (<NUM>, <NUM>) constrained to linear motion along the guide track, wherein rotation of the drive finger about the handle joint drives a linear motion of the guide follower along the guide track.