Patent Description:
Clutches have been successfully deployed in automotive applications to drive cooling fans and pumps. Viscous clutches, in particular, are desirable for many automotive and industrial equipment applications because they are able to control torque transmission over a relatively wide speed range. Viscous clutches are also desirable due to the use of a shearing fluid as the torque transfer mechanism, because shearing fluid (for example, silicone oil) has a relatively long service and life and is generally maintenance free.

There is an automotive market segment that uses viscous clutches that are mounted to drive hubs rather than directly to an engine crankshaft. These drive hubs are rigidly attached to the engine block and provide input rotational speed from an engine through a belt that couples to the viscous clutch shaft with a pulley (also called a sheave). The viscous clutch then provides rotational speed to the fan or other output as needed or desired. Examples of such clutch assemblies include that disclosed in <CIT> and the RCV®<NUM> fully-variable fan drive available from Horton, Inc. (Roseville, MN, USA).

However, direct mounted drive hubs present a number of challenges. For example, clutch assemblies with separate pulleys can have a relatively high part count, which can both increase the number of steps to fabricate the clutch assembly but can also lead to additional labor expenditure to install and/or maintain the clutch assembly. Moreover, <FIG> of <CIT>, for instance, discloses a prior art drive hub configuration in which the pulley bearings are secured on a stationary journal bracket shaft by a nut accessible only from the front, while a pulley and clutch shaft are connected together by other fasteners. In that prior art configuration, removal of the pulley bearings from the journal bracket shaft first requires removal of the pulley, which increases the overall effort by a mechanic. Fasteners orientated parallel to the axis of rotation are difficult to access and not readily visible for the mechanic, increasing maintenance time. Such fasteners for mounting a pulley are especially difficult to access due to their positions, typically facing forward at or near a rear of the clutch assembly behind and/or obstructed by various components of the clutch assembly. In order to provide adequate clearance for access to such fasteners, portions of the clutch assembly may be prohibited from occupying a space adjoining the location of such fasteners, thus limiting the range of options for the configuration of the clutch assembly and/or increasing the overall axial dimensions of the assembly when installed.

Furthermore, when viscous clutches are used, there is a requirement to functionally hold a coil/activation/control assembly and associated cable against rotation. Typically, this anti-rotation function is achieved by connecting the cable and/or coil assembly to another stationary point on the engine. It is then possible to provide electrical current to the coil/activation assembly, which selectively activates the viscous clutch valve in order to control the amount of viscous shearing fluid in a working chamber of the clutch and, thus, the output rotational speed of the clutch.

Also, when using a viscous clutch, the control of the clutch is either handled by an engine control unit or engine control module (ECU/ECM) or a separate clutch controller external to the ECU/ECM. When an external controller is used, it translates ECU/ECM signals into a usable signal to actuate the clutch valve. When an external controller is used, it is necessary to secure the controller somewhere stationary (that is, non-rotating) in the engine compartment. The external controller is operatively connected to the ECU/ECM and the clutch coil assembly.

However, belts located in close proximity to the external controller, whether those belts are connected to the clutch or other components in the engine compartment, may break or "buck" during operation. Belt breakage or "bucking" events may produce belt contact with the external controller and/or cable(s) or wire(s), which can damage the external controller and/or cable(s) or wire(s).

In one aspect, a clutch assembly includes a journal bracket assembly having a base, a stub shaft that extends axially from the base, and a passage that extends through the base and the stub shaft between opposite front and rear openings, a threaded bracket journal threadably coupled to the stub shaft and accessible through the rear opening of the passage, pulley bearings supported on the threaded bracket journal in a radial direction, an integrated pulley/shaft including a pulley and a center shaft, and a clutch mechanism. The journal bracket assembly is rotationally stationary. The center shaft includes a cup-like hub and a distal portion that extends axially from the cup-like hub. The cup-like hub is supported on the pulley bearings, which are located at least partially within a hollow interior area of the cup-like hub. The threaded bracket journal is located at least partially within the hollow interior area of the cup-like hub. The hollow interior area of the cup-like hub is blind from front and radial directions. The clutch mechanism is supported on the distal portion of the center shaft, with the distal portion of the center shaft defining an axis of rotation of the clutch mechanism.

In another aspect, a method of making a clutch assembly includes installing pulley bearings on a threaded bracket journal, installing an integrated pulley/shaft on the pulley bearings, with the pulley bearings positioned at least partially within a blind interior area of a cup-like hub of the integrated pulley/shaft, installing a coil assembly on the integrated pulley/shaft after the integrated pulley/shaft is installed on the integrated pulley/shaft, installing a housing base on the integrated pulley/shaft after the coil assembly is installed on the integrated pulley/shaft, installing a rotor assembly on the integrated pulley/shaft after the housing base is installed on the integrated pulley/shaft, installing a housing cover on the integrated pulley/shaft after the rotor assembly is installed on the integrated pulley/shaft, assembling a journal bracket assembly to the threaded bracket journal after the housing cover is installed on the integrated pulley/shaft, engaging a tool with a torque feature of the threaded bracket journal to threadably couple the threaded bracket journal and the journal bracket assembly. The tool is inserted through a rear opening and into a passage in the journal bracket assembly.

In yet another aspect, an integrated anti-rotation bracket (ARB) and guard assembly suitable for use with a clutch includes a body portion that extends axially, a flange that extends from the body portion, a barrier that extends from the body portion and is axially spaced from the flange, a mounting extension that extends from the body portion, and a harness attached to the mounting extension at a location aligned with the barrier in an axial direction.

The present summary is provided only by way of example, and not limitation. Other aspects of the present invention will be appreciated in view of the entirety of the present disclosure, including the entire text, claims and accompanying figures.

While the above-identified figures set forth one or more embodiments of the present invention, other embodiments are also contemplated, as noted in the discussion. In all cases, this disclosure presents the invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope of the invention defined in the claims. The figures may not be drawn to scale, and applications and embodiments of the present invention may include features, steps and/or components not specifically shown in the drawings.

In one aspect, the present invention relates to a clutch assembly suitable for mounting a clutch, such as a fan clutch, to a mounting location in an engine compartment. Embodiments of the clutch assembly can include a journal bracket (or simply a "bracket") with a stub shaft having a passage that extends entirely through the sub shaft and has openings at opposite front and rear sides or ends, plus a threaded bracket journal that can be threadably engaged with the stub shaft to secure a pulley bearing, an integrated pulley/shaft, and/or the like to the stub shaft. A clutch mechanism can be supported by an engagement with the shaft of the integrated pulley/shaft with the integrated pulley/shaft providing a torque input to the clutch mechanism via a "live" center shaft portion of the integrated pulley/shaft. Tooling can be engaged with the threaded bracket journal through the passage in the journal bracket stub shaft in order to apply torque to tighten the threaded engagement between those components. Such tooling can be inserted from a rear opening of the passage even when the front opening is obstructed by other components, such as by the integrated pulley/shaft, the clutch mechanism, or the like. In this way, a secure connection between the integrated pulley/shaft and the stub shaft can be made in a blind or semi-blind manner. Among other benefits, such a configuration of the clutch assembly further permits the relatively massive journal bracket components to be assembled close to the end of the manufacturing process, so that in an assembly-line type manufacturing environment only a smaller and lighter workpiece (without the heavy journal bracket) needs to be moved through most of the manufacturing and assembly stations. In some embodiments, the integrated pulley/shaft to be a single monolithic piece in some embodiments, which helps to limit total part count, reduce mass, and limit part clearance spacing requirements. In other embodiments, the integrated pulley/shaft can be made up of separate pulley and shaft components connected together, such as with suitable fasteners, which helps simplify casting, machining, and/or other steps used to fabricate the integrated pulley/shaft while still allowing for limited part clearance spacing requirements, among other benefits. An associated method of making and using a clutch assembly is also disclosed.

In another aspect, the present invention relates to an integrated anti-rotation bracket (ARB) and guard, which can be installed so as to engage both the journal bracket and a coil assembly of the clutch mechanism. The integrated ARB and guard, when installed, provides an anti-rotation function to resist or prevent rotation of the coil assembly and further acts as a guard to shield and protect a controller, cables, wires, and/or other components from contact with a belt. Among other features and benefits, the integrated ARB and guard further can provide a mounting location for an external clutch controller (for instance, an optional Di+® controller available from Horton, Inc. , Roseville, MN, USA). The integrated ARB and guard can be utilized with the presently-disclosed clutch mounting assembly or in other applications.

The present application claims priority to <CIT>.

<FIG> is a schematic illustration of an embodiment of a cooling system <NUM> that includes an engine compartment <NUM>, an internal combustion engine <NUM>, a heat exchanger (H/X) <NUM>, a fan <NUM>, a clutch assembly <NUM>, and a belt <NUM>. The clutch assembly <NUM> of the illustrated embodiment includes a clutch mechanism <NUM>, a journal bracket (or drive hub) assembly <NUM>, and a pulley (also called a sheave) or integrated pulley/shaft <NUM>. The belt <NUM> transmits torque from the internal combustion engine <NUM> to the integrated pulley/shaft <NUM>, which in turn transmits torque to the clutch mechanism <NUM>. The clutch mechanism <NUM> selectively controls torque transmission from the
integrated pulley/shaft <NUM> to the fan <NUM>. The fan <NUM> can be a cooling fan and can generate airflows through the heat exchanger <NUM> and/or around the internal combustion engine <NUM>. The journal bracket assembly <NUM> permits the clutch mechanism <NUM> to be mounted to a mounting location within the engine compartment <NUM>, such as being mounted to an engine block of the internal combustion engine <NUM>. The clutch mechanism <NUM> is a viscous clutch, which can be controlled using an electromagnetic control scheme of a type known in the art.

<FIG> and <FIG> illustrate an embodiment of a clutch assembly <NUM>. <FIG> is a perspective view of the clutch assembly <NUM> and <FIG> is a cross-sectional view of the clutch assembly <NUM>, taken along line <NUM>-<NUM> of <FIG>. The clutch assembly <NUM> of the illustrated embodiment includes a clutch (or clutch mechanism) <NUM>, a journal bracket assembly <NUM>, an integrated pulley/shaft <NUM>, and a threaded bracket journal <NUM>. The clutch mechanism <NUM> is rotatable about an axis of rotation A.

The clutch mechanism <NUM> in the illustrated embodiment is configured as a viscous clutch having a coil (or control) assembly <NUM>-<NUM>, a rotor assembly <NUM>-<NUM>, and a housing assembly <NUM>-<NUM> with a housing base <NUM>-3B and a housing cover <NUM>-3C. Together with a suitable pump, the coil assembly <NUM>-<NUM> can electromagnetically control operation of the clutch mechanism <NUM>, such as by generating magnetic flux that actuates a valve assembly to control the amount of a viscous shear fluid present in a working chamber that adjoins both the rotor assembly <NUM>-<NUM> and the housing assembly <NUM>-<NUM>. The general operation of viscous clutches is known. In the illustrated embodiment, the rotor assembly <NUM>-<NUM> functions as a torque input and the housing assembly <NUM>-<NUM> functions as a torque output, and the coil assembly <NUM>-<NUM> is located axially in between the housing assembly <NUM>-<NUM> and the pulley <NUM>-<NUM>. A reservoir for holding a supply of the shear fluid can be carried by the rotor assembly <NUM>-<NUM> so as to rotate whenever there is a torque input to the clutch mechanism <NUM>. A fan or other output device (not shown in <FIG> and <FIG>, but see <FIG>) can be attached to the housing assembly <NUM>-<NUM> in a suitable manner (for example, with threaded studs) to accept a torque output from the clutch mechanism <NUM> during operation. In the illustrated embodiment, the clutch mechanism <NUM> has a "live center" configuration and is supported by and on the integrated pulley/shaft <NUM>, as discussed further below. It is further noted that the particular configuration of the clutch mechanism <NUM> is shown merely by way of example and not limitation. Various other viscous clutch configurations can be utilized in alternative embodiments as will be recognized by persons of ordinary skill in the art, including different reservoir, valve, and control assembly configurations.

The journal bracket assembly <NUM> (or simply the "bracket" or "journal bracket") has a generally radially-extending base or flange <NUM>-<NUM> that can be attached to a desired mounting location, plus a stub shaft <NUM>-<NUM> that extends axially from the base <NUM>-<NUM>. The journal bracket assembly <NUM> is rotationally fixed relative to a mounting location so as to be rotationally stationary during use. In the illustrated embodiment, the base <NUM>-<NUM> is asymmetrical relative to the axis of rotation A. The stub shaft <NUM>-<NUM> can have a generally cylindrical or sleeve-like shape and can be arranged coaxially with the axis of rotation A. A passage <NUM>-<NUM> extends through the stub shaft <NUM>-<NUM> and the base <NUM>-<NUM> of the journal bracket assembly <NUM>, with front and rear openings <NUM>-3F and <NUM>-3R at opposite front and rear sides, respectively. The passage <NUM>-<NUM> extends axially in the illustrated embodiment. In this sense, the stub shaft <NUM>-<NUM> has essentially a hollow construction. The passage <NUM>-<NUM> can be aligned with a center of the stub shaft <NUM>-<NUM> and/or can be aligned with the axis of rotation A. The rear opening <NUM>-3R can permit a tool to be inserted into the passage <NUM>-<NUM> (as discussed further below), and the passage <NUM>-<NUM> can include threads at or near the front opening <NUM>-3F. In the illustrated embodiment, the stub shaft <NUM>-<NUM> is internally threaded along the passage <NUM>-<NUM> at or near the front opening <NUM>-3F. The stub shaft <NUM>-<NUM> has a distal end <NUM>-2D located generally opposite the base <NUM>-<NUM>.

The integrated pulley/shaft <NUM> includes a pulley <NUM>-<NUM> and a center shaft <NUM>-<NUM>. In the illustrated embodiment of <FIG> and <FIG>, the pulley <NUM>-<NUM> and the center shaft <NUM>-<NUM> are discrete components connected together with fasteners <NUM>-<NUM> to form a unit. The clutch mechanism <NUM>, including the coil assembly <NUM>-<NUM>, the rotor assembly <NUM>-<NUM>, and the housing assembly <NUM>-<NUM>, are supported by the integrated pulley/shaft <NUM>. In the illustrated embodiment, the rotor assembly <NUM>-<NUM> is rotationally fixed to the center shaft <NUM>-<NUM>, the housing assembly <NUM>-<NUM> is rotationally supported on the center shaft <NUM>-<NUM> by housing bearings, and the coil assembly <NUM>-<NUM> is supported on the center shaft <NUM>-<NUM> by coil bearings in a rotationally fixed manner as discussed further below. Moreover, in the illustrated embodiment the center shaft <NUM>-<NUM> includes a distal portion <NUM>-2D toward the front, a cup-like hub or web <NUM>-<NUM> toward the rear, and one or more flanges <NUM>-2F. The distal portion <NUM>-2D can have a generally solid (that is, non-hollow) cylindrical shape, and in some embodiments can be made of a flux-conductive material like steel to form part of a flux circuit to electromagnetically actuate the clutch mechanism <NUM>. The distal portion <NUM>-2D can extend axially from the cup-like hub <NUM>-<NUM> in a cantilevered configuration. The cup-like hub <NUM>-<NUM> can have a generally cylindrically shaped rear portion with a hollow interior area <NUM>-2I as well as a forward connecting portion that extends over a radial distance to connect with the center shaft <NUM>-<NUM>. An outer race of pulley bearings <NUM> can contact and engage the cup-like hub <NUM>-<NUM> at the hollow interior area <NUM>-2I, and can be held in place in the axial direction with a retainer <NUM> such as a snap ring. For example, the retainer <NUM> can be engaged with the cup-like hub <NUM>-<NUM> and be located adjacent to the pulley bearings <NUM> at a rear side opposite the distal portion <NUM>-2D of the center shaft <NUM>-<NUM>. In the illustrated embodiment, the cup-like hub <NUM>-<NUM> surrounds the pulley bearing <NUM> on substantially three sides, in a way that makes a front end of the journal bracket assembly <NUM> and the threaded bracket journal <NUM> "blind", that is, inaccessible for a tool from the front and/or radial directions. Moreover, the base <NUM>-<NUM> of the journal bracket assembly <NUM> and other components of the clutch assembly <NUM> may limit access from the rear to the area in which the pulley bearings <NUM> and the retainer <NUM> are positioned. The flange(s) <NUM>-2F can extend radially outward from the cup-like hub <NUM>-<NUM> and the pulley <NUM>-<NUM> can be attached to the flange(s) <NUM>-2F with the fasteners <NUM>-<NUM>. The fasteners <NUM>-<NUM> can be arranged axially, though as will be clear from the present disclosure, access to the fasteners <NUM>-<NUM> after the integrated pulley/shaft <NUM> is initially assembled during manufacturing of the clutch assembly <NUM> is not necessary in view of other features of the clutch assembly <NUM> including the threaded bracket journal <NUM>.

The integrated pulley/shaft <NUM> can be adjusted for each application. For example, the pulley geometry, diameter, and overall shaft/pulley axial length can be adjusted as desired for particular applications. Moreover, the configuration of the integrated pulley/shaft <NUM> can be adjusted independently from that of the journal bracket assembly <NUM> in a modular manner.

A threaded bracket journal <NUM> is threadably engaged with the stub shaft <NUM>-<NUM> at or near the distal end <NUM>-2D of the stub shaft <NUM>-<NUM>. As shown in the illustrated embodiment, a direct threaded connection is made between the stub shaft <NUM>-<NUM> and the threaded bracket journal <NUM> at or near the front opening <NUM>-3F, though in alternate embodiments an indirect connection could be provided, such as with an intermediate threaded sleeve or the like. As explained further below, the threaded bracket journal <NUM> removably attaches the integrated pulley/shaft <NUM> to the stub shaft <NUM>-<NUM> and the rest of the journal bracket assembly <NUM>. In the illustrated embodiment, the threaded bracket journal <NUM> is located at least partially within the hollow interior area <NUM>-2I of the cup-like hub <NUM>-<NUM> such that there is no access to the threaded bracket journal <NUM> from the front or radial direction when the integrated pulley/shaft <NUM> is installed.

In the illustrated embodiment of <FIG> and <FIG>, the threaded bracket journal <NUM> includes generally a cylindrically shaped body <NUM>-<NUM>, with one or more torque features <NUM>-<NUM>, threads <NUM>-<NUM> at an outer or exterior location at or near one end, and with a flange <NUM>-<NUM> at an opposite end to act as a bearing stop. The integrated pulley/shaft <NUM> is rotatably supported on the threaded bracket journal <NUM> by pulley (or sheave) bearings <NUM>. One or more race(s) of the pulley bearings <NUM> can directly contact and rest upon the body <NUM>-<NUM> of the threaded bracket journal <NUM>, as shown in the illustrated embodiment. Moreover, in the illustrated embodiment, the body <NUM>-<NUM> of the threaded bracket journal <NUM> has a slightly smaller diameter at a rear end at the threads <NUM>-<NUM> than at an axially middle portion on which the pulley bearings <NUM> rest. The body <NUM>-<NUM> of the threaded bracket journal <NUM> can have an outer dimension (such as an outer diameter) at the portion where the pulley bearings <NUM> rest that is slightly smaller than a corresponding outer dimension (such as an outer diameter) of the stub shaft <NUM>-<NUM>, and an inner race of the pulley bearings <NUM> can have an inner diameter that is smaller than an outer diameter of the stub shaft <NUM>-<NUM> at the distal end <NUM>-2D, such that tightening the threaded engagement of the stub shaft <NUM>-<NUM> and the threaded bracket journal <NUM> creates a generally axial clamping force to secure the pulley bearings <NUM>. The clamping force produced with the threaded bracket journal <NUM> can be applied to the inner race of the pulley bearings <NUM> between the flange <NUM>-<NUM> of the threaded bracket journal <NUM> and the distal end <NUM>-2D of the stub shaft <NUM>-<NUM>. In further embodiments, a stop or flange can be provided on the stub shaft <NUM>-<NUM> that contacts the pulley bearing <NUM> to react the clamping load in addition to or instead of the distal end <NUM>-2D of the stub shaft <NUM>-<NUM>. The torque feature(s) <NUM>-<NUM> can be tooling engagement faces to accept an Allen wrench, bit (for instance, a Torx® or Robertson bit), screwdriver, or another suitable tool. In the illustrated embodiment of <FIG> and <FIG>, the torque features <NUM>-<NUM> are arranged at a rear end of the body <NUM>-<NUM> and extend only partly into an interior of the body <NUM>-<NUM> in the axial direction, with the torque features <NUM>-<NUM> exposed to the passage <NUM>-<NUM>. To secure the pulley bearing <NUM> in place, the threaded bracket journal <NUM> threadably mates with the stub shaft <NUM>-<NUM> of the journal bracket assembly <NUM>. The threaded bracket journal <NUM> threads into (or, alternatively, onto) the stub shaft <NUM>-<NUM> thereby securing the pulley bearing <NUM> into place, which can be by way of an axial clamping force.

In the illustrated embodiment, the journal bracket assembly <NUM> and threaded bracket journal <NUM> are stationary, that is, they do not rotate when in use (though they may be in a vehicle that is movable). During operation, the integrated pulley/shaft <NUM> and the fixedly attached rotor assembly <NUM>-<NUM> of the clutch mechanism <NUM> can spin together at an input rotational speed with torque provided to the pulley <NUM>-<NUM> by a belt, which in turn is powered by an internal combustion engine or another prime mover (see <FIG>). The clutch housing assembly <NUM>-<NUM> (including the housing base <NUM>-3B and cover <NUM>-3C) and attached output device (such as a fan) can then rotate at a commanded output speed as a function of the operation of the clutch mechanism <NUM> (for instance, as a function of the amount of viscous shear fluid present in a working chamber where the clutch mechanism <NUM> is configured as a viscous clutch).

The pulley <NUM>-<NUM>, the cup-like hub <NUM>-<NUM>, the fasteners <NUM>-<NUM>, the body <NUM>-<NUM> of the threaded bracket journal <NUM>, and the pulley bearings <NUM> can be axially aligned, or at least can partially overlap each other in the axial direction. In this way, forces applied to the pulley <NUM>-<NUM> by a belt can be substantially aligned with the pulley bearings <NUM>, which can help reduce the magnitude of forces and loads that must be supported by the center shaft <NUM>-<NUM>. Some or all of the forces applied to the pulley bearings <NUM> are transmitted through the threaded bracket journal <NUM> when the clutch assembly <NUM> is installed and under load. In this respect, the threaded journal bracket <NUM> carries overhung loads transmitted through the pulley bearings <NUM>, and is not merely used to generate axial clamping force like a threaded nut. As shown in the illustrated embodiment, the rear opening <NUM>-3R of the passage <NUM>-<NUM> through the base <NUM>-<NUM> and the stub shaft <NUM>-<NUM> of the journal bracket assembly <NUM> allows a suitable tool to be inserted from the rear to secure the threaded bracket journal <NUM> to the stub shaft <NUM>-<NUM> (for instance, to rotate the threaded bracket journal <NUM> relative to the stub shaft <NUM>-<NUM> to tighten the threads <NUM>-<NUM>). At the same time, the integrated pulley/shaft <NUM> can be constructed as a unit, with the cup-like hub <NUM>-<NUM> (plus the center shaft <NUM>-<NUM>) surrounding the pulley bearings <NUM> on substantially three sides, in a way that makes the front end of a subassembly including the threaded bracket journal <NUM> and the journal bracket assembly <NUM> "blind", that is, inaccessible for a tool from the front and radial directions. This allows for an advantageous configuration of the integrated pulley/shaft <NUM> (and of the clutch mechanism <NUM>) while still allowing the integrated pulley/shaft <NUM> to be rotatably secured to and supported on the stub shaft <NUM>-<NUM> by way of the pulley bearings <NUM>.

The disclosed embodiments of the clutch assembly provide numerous features and benefits, including a relatively low part count, a relatively small first-groove-to-fan-mount axial length L of the assembly (which can be characterized as an axial projected distance from a first or rearmost groove of the pulley to the mounting location of the fan, as indicated in <FIG>), avoidance of a need for clearance space between the pulley and viscous clutch to place and attach coupling fasteners or get an assembly tool in place in that location, and the absence of a threaded hex shaft or bolted flange shaft joint that needs to be accessible during maintenance (after installation and use). Furthermore, the threaded bracket journal allows the journal bracket assembly to be attached to the rest of the clutch assembly last (or as one of the last few steps) during fabrication so that the relatively large and massive journal bracket assembly is not required to be moved through an entire assembly line, which allows for implementation of more assembly automation, common fixturing, and quicker assembly, while still allowing for a modular bracket and integrated pulley/shaft design.

<FIG> and <FIG> also show an embodiment of an integrated anti-rotation bracket (ARB) and guard <NUM> installed as part of the clutch assembly <NUM>. In general, the integrated ARB and guard <NUM> provides an anti-rotation attachment/connection point for the coil assembly <NUM>-<NUM>, by providing a substantially rigid and rotationally fixed connection from the coil assembly <NUM>-<NUM> to the stationary (that is, non-rotating) journal bracket assembly <NUM>, and also guards electrical components from belt breakage or "bucking" events. As shown in the illustrated embodiment, the integrated ARB and guard <NUM> includes a flange <NUM>-<NUM>, base portion <NUM>-<NUM>, a barrier <NUM>-<NUM>, a gusset <NUM>-<NUM>, and a mounting extension <NUM>-<NUM>.

The flange <NUM>-<NUM> can extend radially or tangentially with respect to the axis of rotation A and can be secured to the journal bracket assembly <NUM> with suitable fasteners or the like. In the illustrated embodiment, a portion of the flange <NUM>-<NUM> is positioned at least partially in and secured to a recess or notch in the base <NUM>-<NUM> of the journal bracket assembly <NUM> with threaded fasteners at a location radially outward from the stub shaft <NUM>-<NUM>.

The base portion <NUM>-<NUM> can extend axially away from the flange <NUM>-<NUM> and can overlap with the pulley <NUM>-<NUM> of the integrated pulley/shaft assembly <NUM> in the axial direction. The barrier <NUM>-<NUM> can extend from the base portion <NUM>-<NUM> and can be aligned or at least partially overlap with the pulley <NUM>-<NUM> at a location adjacent to the pulley <NUM>-<NUM> and axially spaced from the flange <NUM>-<NUM>. As shown most clearly in <FIG>, the barrier <NUM>-<NUM> can be configured to extend substantially perpendicular to an adjoining region of the base portion <NUM>-<NUM> to one side of the base portion <NUM>-<NUM>, such that the barrier <NUM>-<NUM> is roughly (though not precisely) tangential to the pulley <NUM>-<NUM>. The barrier <NUM>-<NUM> helps provide rigidity to the integrated ARB and guard <NUM> but also provides a web of material that helps physically isolate the belt (not shown) engaged with the pulley <NUM>-<NUM> from sensitive electrical components.

The gusset <NUM>-<NUM> links the flange <NUM>-<NUM> and the base portion <NUM>-<NUM> to help increase rigidity and structural strength. In the illustrated embodiment, a U-shaped channel separates the barrier <NUM>-<NUM> from the gusset <NUM>-<NUM> in the axial direction. The mounting extension <NUM>-<NUM> protrudes from the base portion <NUM>-<NUM> at an oblique angle, for example, the mounting extension <NUM>-<NUM> can be angled so as to be arranged substantially radially with respect to the axis of rotation A. The mounting extension <NUM>-<NUM> provides an anti-rotation attachment point for the coil assembly <NUM>-<NUM>, with the integrated ARB and guard <NUM> as a whole providing a substantially rigid connection from the coil assembly <NUM>-<NUM> to the stationary (that is, non-rotating) journal bracket assembly <NUM>. This allows the coil assembly <NUM>-<NUM> to resist rotation induced by, for instance, friction in the coil bearings that rotatably support the coil assembly <NUM>-<NUM> on the rotatable center shaft <NUM>-<NUM>. Moreover, in this way, generally opposite ends of the integrated ARB and guard <NUM> can be connected to the journal bracket assembly <NUM> and the coil assembly <NUM>-<NUM>.

A cable <NUM> containing suitable wiring can extend from the coil assembly <NUM>-<NUM> to a power supply, an external clutch controller, an engine controller, an overall vehicle controller, or the like (not shown). The cable <NUM> can be secured to the integrated ARB and guard <NUM> with a harness <NUM>, located at or near a front end of the mounting extension <NUM>-<NUM> (and a front end of the base portion <NUM>-<NUM>), with the cable <NUM> protected by the barrier <NUM>-<NUM> and the base portion <NUM>-<NUM>. The mounting extension <NUM>-<NUM> can include fastener openings, clamp points, or the like to facilitate the attachment of electrical components. In the illustrated embodiment, the harness <NUM> is attached to the mounting extension <NUM>-<NUM> at a location that is aligned with the barrier <NUM>-<NUM> in the axial direction.

In further embodiments a controller can be attached to the mounting extension <NUM>-<NUM>. In some embodiments, the controller can be utilized as an external electronic closed loop clutch controller to convert control signals from an engine or vehicle controller into commands that operate the coil assembly <NUM>-<NUM>, among other functions. For example, the controller can be or function similarly to a Di+® controller (available from Horton, Inc. , Roseville, MN, USA). Such a controller can alternatively be located remotely from the integrated ARB and guard <NUM>.

The particular shape and configuration of the integrated ARB and guard <NUM> shown in <FIG> and <FIG> is provided merely by way of example and not limitation. In alternate embodiments, the integrated ARB and guard <NUM> can have a different configuration; for instance, the mounting extension <NUM>-<NUM> could be admitted and components connected directly to the base portion <NUM>-<NUM>. Likewise, the gusset <NUM>-<NUM> could be omitted in further embodiments.

The integrated ARB and guard <NUM> provides multiple functions and numerous benefits. For example, the integrated ARB and guard <NUM> provides anti-rotation functionality for the coil assembly <NUM>-<NUM> and the associated cable <NUM>. Moreover, the integrated ARB and guard <NUM> provides protection to the wires/cables and other electrical components in case of a sudden belt break or belt "buck" event, which can be achieved in part by positioning the base portion <NUM>-<NUM> and/or the barrier <NUM>-<NUM> between the pulley <NUM>-<NUM> and the cable <NUM>. Such protection is available even when using a viscous clutch mechanism with a "live center" configuration that generally precludes running wires or cables through the interior of the rotatable "live" center shaft <NUM>-<NUM>. These benefits result in less maintenance and longer uptime for the clutch assembly <NUM>. Additionally, the integrated ARB and guard <NUM> provides a location and structural features to mount an optional (external) clutch controller, which can further be protected by the base portion <NUM>-<NUM> and/or the barrier <NUM>-<NUM>. With the controller attached, such as in a pre-attached manner, the integrated ARB and guard <NUM> with the controller provides a "plug and play" clutch solution for end users, which reduces installation work for the end user.

<FIG> is a cross-sectional view of another embodiment of a clutch assembly <NUM>. The clutch assembly <NUM> has a configuration and function similar to that of the clutch assembly <NUM> described above. As such, similar reference numbers are used in <FIG> with those reference numbers increased by one hundred compared to those used in <FIG> and <FIG>. For instance, the clutch assembly <NUM> of the illustrated embodiment includes a clutch (or clutch mechanism) <NUM>, a journal bracket assembly <NUM>, an integrated pulley/shaft <NUM>, and a threaded bracket journal <NUM>. The clutch mechanism <NUM> is rotatable about an axis of rotation A, and includes a coil assembly <NUM>-<NUM>, a rotor assembly <NUM>-<NUM>, and a housing assembly <NUM>-<NUM> (with a housing base <NUM>-3B and a housing cover <NUM>-3C). The journal bracket assembly <NUM> includes a generally radially-extending flange <NUM>-<NUM> and a stub shaft <NUM>-<NUM> having a distal end <NUM>-2D located generally opposite the base <NUM>-<NUM>. An axial passage <NUM>-<NUM> extends through the base <NUM>-<NUM> and a center of the stub shaft <NUM>-<NUM>, with front and rear openings <NUM>-3F and <NUM>-3R at opposite front and rear sides, respectively. The rear opening <NUM>-3R can permit a tool to be inserted into the passage <NUM>-<NUM>, and the passage <NUM>-<NUM> can include threads at or near the front opening <NUM>-3F. In the illustrated embodiment, the stub shaft <NUM>-<NUM> is internally threaded along the passage <NUM>-<NUM> at or near the front opening <NUM>-3F. The integrated pulley/shaft <NUM> includes a pulley <NUM>-<NUM> and a center shaft <NUM>-<NUM> with a "live" configuration. The center shaft <NUM>-<NUM> includes a distal portion <NUM>-2D toward the front, a cup-like hub or web <NUM>-<NUM> toward the rear. The distal portion <NUM>-2D can have a generally solid (that is, non-hollow) cylindrical shape. The cup-like hub <NUM>-<NUM> can have a generally cylindrically shaped rear portion with a hollow interior area <NUM>-2I as well as a forward connecting portion that extends over a radial distance to connect with the center shaft <NUM>-<NUM>. A threaded bracket journal <NUM> is threadably engaged with the stub shaft <NUM>-<NUM> at or near the distal end <NUM>-2D of the stub shaft <NUM>-<NUM>. As shown in the illustrated embodiment, a direct threaded connection is made between the stub shaft <NUM>-<NUM> and the threaded bracket journal <NUM> at or near the front opening <NUM>-3F, though in alternate embodiments an indirect connection could be provided, such as with an intermediate threaded sleeve or the like. Moreover, in the illustrated embodiment, the threaded bracket journal <NUM> has a hollow cylindrical shape, with a center opening that passes entirely through a body <NUM>-<NUM>. The threaded bracket journal <NUM> further includes threads <NUM>-<NUM> and a flange <NUM>-<NUM>. An outer race of pulley bearings <NUM> can contact and engage the cup-like hub <NUM>-<NUM> at the hollow interior area <NUM>-2I, and can be held in place in the axial direction with a retainer <NUM> such as a snap ring, with an inner race of the pulley bearings <NUM> supported on the threaded bracket journal <NUM>. In the illustrated embodiment, the cup-like hub <NUM>-<NUM> surrounds the pulley bearing <NUM> on substantially three sides, in a way that makes a front end of the journal bracket assembly <NUM> and the threaded bracket journal <NUM> "blind", that is, inaccessible for a tool from the front and radial directions. The threaded bracket journal <NUM> can axially clamp the pulley bearings <NUM>, while also providing support for the pulley bearings <NUM> in a radial direction.

In the illustrated embodiment of <FIG>, the pulley <NUM>-<NUM> and the center shaft <NUM>-<NUM> are integrated into one monolithic component. In this respect, the pulley <NUM>-<NUM> and the center shaft <NUM>-<NUM> are inseparable in the illustrated embodiment. Such a configuration of the integrated pulley/shaft <NUM> helps to further reduce part count compared to the embodiment of the integrated pulley/shaft <NUM> of <FIG> and <FIG>, but at the same time, as trade-offs, reduces design modularity and increases applications-specific design and manufacturing efforts.

The clutch assembly <NUM> also includes an integrated ARB and guard <NUM>. As shown in the illustrated embodiment, the integrated ARB and guard <NUM> is a generally horizontally or axially-extending structure that is the secured to both the journal bracket assembly <NUM> and the coil assembly <NUM>-<NUM> of the clutch mechanism <NUM> at a location radially outward from the pulley <NUM>-<NUM> (and an associated belt). In the illustrated embodiment, the integrated ARB and guard <NUM> includes a flange <NUM>-<NUM> and a base portion <NUM>-<NUM>. A front end of the base portion <NUM>-<NUM>, which can be stepped radially inwardly, provides an anti-rotation attachment/connection point for the coil assembly <NUM>-<NUM> and an associated cable <NUM>, by providing a substantially rigid connection from the coil assembly <NUM>-<NUM> and the cable <NUM> to the stationary (that is, non-rotating) journal bracket assembly <NUM>. A mounting extension <NUM>-<NUM> can also be provided, which provides a space to mount an optional external controller (not shown).

<FIG> is a flow chart of an embodiment of a method of making a clutch assembly, such as the clutch assemblies <NUM>, <NUM>, or <NUM>. First, the pulley bearings <NUM> or <NUM> are placed on the threaded bracket journal <NUM> or <NUM>, in contact with the flange <NUM>-<NUM> or <NUM>-<NUM> that acts as a bearing stop to create a subassembly (Step <NUM>). Then the integrated pulley/shaft <NUM>, <NUM> or <NUM> is installed (e.g., pressed) onto the subassembly of the pulley bearings <NUM> or <NUM> and the threaded bracket journal <NUM> or <NUM> (Step <NUM>). In embodiments in which the integrated pulley/shaft <NUM> is configured as a unit made up of separate pulley <NUM>-<NUM> and center shaft <NUM>-<NUM> sub-components, those sub-components are secured together (for example with the fasteners <NUM>-<NUM>) to form an integrated unit before installing that unit onto the subassembly of the pulley bearings <NUM> or <NUM> and the threaded bracket journal <NUM> or <NUM> as part of Step <NUM>. A retainer <NUM> or <NUM>, such as a snap ring, can then be installed to at least temporarily retain the pulley bearings <NUM> or <NUM> relative to the integrated pulley/shaft <NUM>, <NUM> or <NUM> (Step <NUM>). Next, the coil assembly <NUM>-<NUM> or <NUM>-<NUM>, including any associated spacer (if used), is installed on the center shaft <NUM>-<NUM> or <NUM>-<NUM> of the integrated pulley/shaft <NUM>, <NUM> or <NUM> (Step <NUM>). Next, the housing base <NUM>-3B or <NUM>-3B, including any inner pole assembly for a flux circuit that transmits flux generated by the coil assembly <NUM>-<NUM> or <NUM>-<NUM> through the clutch mechanism <NUM>, <NUM> or <NUM> during use, is installed on the center shaft <NUM>-<NUM> or <NUM>-<NUM> of the integrated pulley/shaft <NUM>, <NUM> or <NUM> (Step <NUM>). Next, the rotor assembly <NUM>-<NUM> or <NUM>-<NUM> is installed on the center shaft (Step <NUM>). As part of Step <NUM>, or as part of a related but separate Step <NUM>, reaction features can be used to apply assembly torque to a joint between the rotor assembly <NUM>-<NUM> or <NUM>-<NUM> and the center shaft <NUM>-<NUM> or <NUM>-<NUM> with suitable tooling. Next, the housing cover <NUM>-3C or <NUM>-3C is installed onto the housing base <NUM>-3B or <NUM>-3B, which can enclose the rotor assembly <NUM>-<NUM> or <NUM>-<NUM> within the housing assembly <NUM>-<NUM> or <NUM>-<NUM> (Step <NUM>). Lastly, the journal bracket assembly <NUM>, <NUM> or <NUM> is assembled with the threaded bracket journal <NUM> or <NUM> (Step <NUM>). As part of Step <NUM>, or as part of a related but separate Step <NUM>, a suitable tool is engaged with the threaded bracket journal <NUM> or <NUM> through the passage <NUM>-<NUM> or <NUM>-<NUM> in the base <NUM>-<NUM> or <NUM>-<NUM> and the stub shaft <NUM>-<NUM> or <NUM>-<NUM> of the journal bracket assembly <NUM> or <NUM> in order to torque and tighten the threaded connection between those components. The threaded engagement between the threaded bracket journal <NUM> or <NUM> and the stub shaft <NUM>-<NUM> or <NUM>-<NUM> of the journal bracket assembly <NUM> or <NUM> concurrently produces a clamping force on the pulley bearings <NUM> or <NUM>. This clamping force produced with the threaded bracket journal <NUM> or <NUM> in the axial direction can render the pulley bearing retainer <NUM> or <NUM> (such as a snap ring) superfluous, or at least axially unloaded, during later operation of the fully constructed clutch assembly <NUM>, <NUM> or <NUM>.

In embodiments in which the integrated ARB and guard <NUM> or <NUM> is used, the method can further include attaching the integrated ARB and guard <NUM> or <NUM> to the journal bracket assembly <NUM>, <NUM>, <NUM> and securing the coil assembly <NUM>-<NUM> or <NUM>-<NUM> and/or the cable <NUM> or <NUM> to the integrated ARB and guard <NUM> or <NUM> with the harness <NUM> or the like. It is possible to attach the integrated ARB and guard <NUM> or <NUM> to the journal bracket assembly <NUM>, <NUM>, <NUM> either before or after the journal bracket assembly <NUM>, <NUM>, or <NUM> is coupled to the threaded bracket journal <NUM> or <NUM>. Securing the coil assembly <NUM>-<NUM> or <NUM>-<NUM> and/or the cable <NUM> or <NUM> to the integrated ARB and guard <NUM> or <NUM> will occur after the journal bracket assembly <NUM>, <NUM>, or <NUM> is coupled to the threaded bracket journal <NUM> or <NUM>.

Because the journal bracket assembly <NUM>, <NUM> or <NUM> is relatively massive, its installation at Step <NUM> at or near the end of the assembly process means that a much smaller and less massive (that is, lighter) workpiece is involved in preceding Steps <NUM> to <NUM>. This facilitates manufacturing in an assembly-line type of environment, though prior art clutch assemblies typically required earlier assembly of the journal bracket and movement of such a massive workpiece through stations in a factory for most or all of the assembly process.

In light of the entirety of the present disclosure, a method of using the disclosed clutch assembly will be apparent to those of ordinary skill in the art.

A clutch assembly can include a journal bracket assembly having a base, a stub shaft that extends axially from the base, and a passage that extends through the base and the stub shaft between opposite front and rear openings, with the journal bracket assembly being rotationally stationary; a threaded bracket journal threadably coupled to the stub shaft, such that the threaded bracket journal is accessible through the rear opening of the passage; pulley bearings supported on the threaded bracket journal in a radial direction; an integrated pulley/shaft including a pulley and a center shaft, with the center shaft including a cup-like hub and a distal portion that extends axially from the cup-like hub, the cup-like hub being supported on the pulley bearings, the pulley bearings located at least partially within a hollow interior area of the cup-like hub, the threaded bracket journal located at least partially within the hollow interior area of the cup-like hub, and the hollow interior area of the cup-like hub being blind from front and radial directions; and a clutch mechanism supported on the distal portion of the center shaft, with the distal portion of the center shaft defining an axis of rotation of the clutch mechanism.

The clutch assembly of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:.

A method of making a clutch assembly includes installing pulley bearings on a threaded bracket journal; installing an integrated pulley/shaft on the pulley bearing, with the pulley bearings positioned at least partially within a blind interior area of a cup-like hub of the integrated pulley/shaft; installing a coil assembly on the integrated pulley/shaft after the integrated pulley/shaft is installed on the integrated pulley/shaft; installing a housing base on the integrated pulley/shaft after the coil assembly is installed on the integrated pulley/shaft; installing a rotor assembly on the integrated pulley/shaft after the housing base is installed on the integrated pulley/shaft; installing a housing cover on the integrated pulley/shaft after the rotor assembly is installed on the integrated pulley/shaft; assembling a journal bracket assembly to the threaded bracket journal after the housing cover is installed on the integrated pulley/shaft; and engaging a tool with a torque feature of the threaded bracket journal to threadably couple the threaded bracket journal and the journal bracket assembly. The tool is inserted through a rear opening and into a passage in the journal bracket assembly.

The method of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional steps:.

An integrated anti-rotation bracket (ARB) and guard assembly for use with a clutch includes a body portion that extends axially; a flange that extends from the body portion; a barrier that extends from the body portion, the barrier being axially spaced from the flange; a mounting extension that extends from the body portion; and a harness attached to the mounting extension at a location aligned with the barrier in an axial direction.

The integrated ARB and guard assembly of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:.

Any relative terms or terms of degree used herein, such as "substantially", "essentially", "generally", "approximately" and the like, should be interpreted in accordance with and subject to any applicable definitions or limits expressly stated herein. In all instances, any relative terms or terms of degree used herein should be interpreted to broadly encompass any relevant disclosed embodiments as well as such ranges or variations as would be understood by a person of ordinary skill in the art in view of the entirety of the present disclosure, such as to encompass ordinary manufacturing tolerance variations, incidental alignment variations, transient alignment or shape variations induced by thermal, rotational or vibrational operational conditions, and the like. Moreover, any relative terms or terms of degree used herein should be interpreted to encompass a range that expressly includes the designated quality, characteristic, parameter or value, without variation, as if no qualifying relative term or term of degree were utilized in the given disclosure or recitation.

Claim 1:
A clutch assembly (<NUM>; <NUM>; <NUM>) comprising:
a journal bracket assembly (<NUM>; <NUM>; <NUM>) having a base (<NUM>-<NUM>; <NUM>-<NUM>), a stub shaft (<NUM>-<NUM>; <NUM>-<NUM>) that extends axially from the base, and a passage (<NUM>-<NUM>; <NUM>-<NUM>) that extends through the base and the stub shaft between opposite front and rear openings (<NUM>-3F and <NUM>-3R; <NUM>-3F and <NUM>-3R), wherein the journal bracket assembly is rotationally stationary;
pulley bearings (<NUM>; <NUM>);
an integrated pulley/shaft (<NUM>; <NUM>; <NUM>) including a pulley (<NUM>-<NUM>; <NUM>-<NUM>) and a center shaft (<NUM>-<NUM>; <NUM>-<NUM>), wherein the center shaft includes a cup-like hub (<NUM>-<NUM>; <NUM>-<NUM>) and a distal portion (<NUM>-2D; <NUM>-2D) that extends axially from the cup-like hub, wherein the cup-like hub is supported on the pulley bearings, wherein the pulley bearings are located at least partially within a hollow interior area (<NUM>-2I; <NUM>-2I) of the cup-like hub; and
a clutch mechanism (<NUM>; <NUM>; <NUM>) supported on the distal portion of the center shaft, with the distal portion of the center shaft defining an axis of rotation (A) of the clutch mechanism, wherein the clutch mechanism (<NUM>; <NUM>) is a viscous clutch,
characterized by further comprising:
a threaded bracket journal (<NUM>; <NUM>) threadably coupled to the stub shaft, wherein the pulley bearings (<NUM>; <NUM>) are supported on the threaded bracket journal in a radial direction, wherein the threaded bracket journal is accessible through the rear opening of the passage, wherein the threaded bracket journal is located at least partially within the hollow interior area of the cup-like hub, and wherein the hollow interior area of the cup-like hub is blind from front and radial directions.