Continuously variable transmission

A continuously variable transmission housing is provided that includes an inner cover and an outer cover connectable to the inner cover to define an interior chamber. The interior chamber is structured and operable to enclose a continuously variable transmission primary pulley, secondary pulley and pulley belt. The housing includes a duct panel mounted to the inner cover such that when the primary pulley is disposed within the interior chamber, the duct panel is disposed between an outer face of the primary pulley and the inner cover. Moreover, an air duct is defined between the inner cover and the duct panel, wherein the air duct is fluidly connected to ambient air from an ambient environment external to the housing. The duct panel includes a center opening that structured and operable to allow the ambient air to be drawn through the air duct and into the housing interior chamber.

FIELD

The present teachings relate to continuously variable transmissions (CVTs), and more particularly to a CVT cover designed to keep the internal components of the CVT cool.

BACKGROUND

Many of today's lightweight vehicles that are not designated for use on roadways, e.g., all-terrain vehicles (ATVs), utility terrain vehicles (UTVs), etc., implement a continuously variable transmission (CVT) to transfer and control the distribution of torque within the vehicle drivetrain. Due to the dust, water, mud, rocks, etc., commonly encountered in off-road environments, such CVTs typically comprise a housing or cover designed to protect the components, e.g., pulleys, bushings and belts, from the environment. However, such covers substantially enclose the components and trap heat generated during operation of the CVT. More particularly, the air within the cover is not easily exchanged with fresh cooler air and the components cannot cool off, thereby degrading the life of the components.

SUMMARY

In various embodiments, the present disclosure provides a continuously variable transmission housing that includes an inner cover and an outer cover connectable to the inner cover to define an interior chamber. The interior chamber is structured and operable to enclose a continuously variable transmission primary pulley, secondary pulley and pulley belt. The housing additionally includes a duct panel mounted to the inner cover such that when the primary pulley is disposed within the interior chamber, the duct panel is positioned between an outer face of a static sheave of the primary pulley and the inner cover. Moreover, an air duct is defined between the inner cover and the duct panel, wherein the air duct is fluidly connected to ambient air from an ambient environment external to the housing. The duct panel includes a center opening that is structured and operable to allow the ambient air to be drawn through the air duct and into the housing interior chamber.

In various other embodiments, the present disclosure provides a continuously variable transmission (CVT) that comprises a primary pulley operably connectable to an output shaft of a prime mover of a vehicle, a secondary pulley operably connectable to at least one wheel axle of the vehicle, and a pulley belt operably connecting the primary pulley to the secondary pulley to transfer torque from the primary pulley to the secondary pulley. The primary pulley includes a primary pulley shaft operably connectable to the prime mover output shaft, a static sheave fixedly mounted to the primary pulley shaft, and a dynamic sheave structured and operable to controllably move axially along the primary pulley shaft. The CVT additionally comprises a housing that includes an inner cover and an outer cover connectable to the inner cover to define an interior chamber. The interior chamber is structured and operable to enclose a continuously variable transmission primary pulley, secondary pulley and pulley belt. The housing additionally includes a duct panel mounted to the inner cover such that when the primary pulley is disposed within the interior chamber, the duct panel is positioned between an outer face of a static sheave of the primary pulley and the inner cover. Moreover, an air duct is defined between the inner cover and the duct panel, wherein the air duct is fluidly connected to ambient air from an ambient environment external to the housing. The duct panel includes a center opening that is structured and operable to allow the ambient air to be drawn through the air duct and into the housing interior chamber. Furthermore, the outer face of the primary pulley static sheave comprises a plurality of low pressure fins that are structured and operable to generate a vacuum effect at the air duct center opening as the primary pulley is rotated, thereby generating a vacuum effect, or suction, within the air duct that draws the ambient air through the air duct and into the interior chamber of the housing via the duct panel center opening. The housing further includes an exhaust outlet that fluidly connects the interior chamber with the ambient environment. Accordingly, the ambient air drawn into the interior chamber can be circulated around the primary pulley, secondary pulley and pulley belt and exhausted out the exhaust outlet, thereby cooling the components.

This Summary is provided merely for purposes of summarizing various example embodiments of the present disclosure so as to provide a basic understanding of various aspects of the teachings herein. Various embodiments, aspects, and advantages will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. Accordingly, it should be understood that the description and specific examples set forth herein are intended for purposes of illustration only and are not intended to limit the scope of the present teachings.

DETAILED DESCRIPTION

The embodiments disclosed below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art can utilize their teachings. Because many varying and different embodiments may be made within the scope of the concept(s) taught herein, and because many modifications may be made in the embodiments described herein, it is to be understood that the details herein are to be interpreted as only illustrative and non-limiting. As well, it should be understood that the drawings are intended to illustrate and plainly disclose presently envisioned embodiments to one of skill in the art, but are not intended to be manufacturing level drawings or renditions of final products and may include simplified conceptual views to facilitate understanding or explanation. Additionally, the relative size and arrangement of the components may differ from that shown and still operate within the spirit of the invention. Throughout this specification, like reference numerals will be used to refer to like elements.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the” may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms “comprises,” “comprising,” “including,” and “having,” are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps can be employed.

As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, A and/or B includes A alone, or B alone, or both A and B.

Although the terms first, second, third, etc. may be used herein to describe various elements, objects, devices, apparatuses, components, regions or sections, etc., these elements, objects, devices, apparatuses, components, regions or sections, etc., should not be limited by these terms. These terms may be used only to distinguish one element, object, device, apparatus, component, region or section, etc., from another element, object, device, apparatus, component, region or section, etc., and do not necessarily imply a sequence or order unless clearly indicated by the context.

Furthermore, it will be understood that various directions such as “upper”, “lower”, “bottom”, “top”, “left”, “right”, “first”, “second” and so forth are made only with respect to explanation in conjunction with the drawings, and that components may be oriented differently, for instance, during transportation and manufacturing as well as operation.

While the present disclosure is primarily described with regard to a CVT and CVT housing for use in an off-road utility vehicle, it should be understood that the features of the CVT and CVT housing disclosed herein can be applied, within the scope of the disclosure, to other types of vehicles such as most lightweight vehicles that are not designated for use on roadways, e.g., maintenance vehicles, cargo vehicles, shuttle vehicles, golf carts, other all-terrain vehicles (ATVs), utility task vehicles (UTVs), recreational off-highway vehicles (ROVs), side-by-side vehicles (SSV), worksite vehicles, buggies, motorcycles, watercraft, snowmobiles, tactical vehicles, etc.

Referring toFIGS. 1, 2 and 3, in various embodiments, the present disclosure provides an off-road utility vehicle10that generally includes a chassis or frame14, a pair of rear wheels18and a pair of front wheels22operationally connected to the chassis14and/or other frame structure of the vehicle10, and a passenger compartment26. The vehicle10can be any four-wheel drive or two-wheel drive lightweight vehicle that is not designated for use on roadways. The passenger compartment26generally includes a dash console30, a steering wheel34, a floorboard (not shown, but understood), and a passenger seating structure38. The dash console30can include one or more instrument displays, gauges, vehicle control devices and/or storage compartments, e.g., an On/Off key switch, a forward/neutral/reverse selector, one or more small accessory storage pockets, one or more telemetry gauges/readouts (e.g., a speedometer, tachometer, temperature gauge, etc.) an electronic display (e.g., an LCD display that can have touch capabilities), a radio, and/or various other vehicle controls. The steering wheel34is for use by the vehicle operator to control the directional movement of the vehicle10. The floorboard is structured and operable to enclose a bottom of, and provide a floor for, the passenger compartment26.

The seating structure38is structured and operable to provide seating for one or more vehicle occupants, e.g., a driver and one or more passengers, and can include one or more seats. For example, in various embodiments the seating structure38can be a side-by-side seating structure comprising a single row of two or more laterally spaced (with regard to a longitudinal axis of the vehicle10) separate and independent seats. Alternatively, the seating structure38can comprise a single row bench seat capable of seating two or more passengers side-by-side, two rows of bench seats, or two rows of side-by-side seats comprising four or more separate and independent seats, etc.

The vehicle10additionally includes a prime mover42mounted to the chassis14, and a drivetrain44operationally connected to at least one of the front and/or rear wheels22and/or18, and the prime mover42. The prime mover42is structured and operable to generate torque (e.g., motive force, e.g., power) utilized to provide motive force for the vehicle10via the drivetrain44, as described herein. Although the prime mover42is primarily described herein as an internal combustion engine (ICE), it should be understood that the prime mover42can be an electric motor, a hybrid combination of an ICE and an electric motor, or any other suitable motor or engine and remain within the scope of the present disclosure. In embodiments in which the prime mover42is embodied as or comprises an ICE, the ICE can be configured to utilize any suitable combustible fuel, such as gasoline, diesel, natural gas, biofuel, some combination thereof, etc.

Still further, in various embodiments, the vehicle10can include a roll over protection system (ROPS)48that is disposed above and around at least a portion of the passenger compartment26and is structured and operable to protect passengers within the passenger compartment26in a situation where the vehicle10may be caused to overturn or roll over. The ROPS48comprises a plurality of tubes, bars or beams that are connected to the chassis14and extend above, over and around at least a portion of the passenger compartment26. The ROPS48can be constructed or fabricated of any material having sufficient strength and rigidity to provide protection to the passengers of the vehicle10should the vehicle10be upset and turned on its side or rolled over, e.g., steel, aluminum, titanium, carbon fiber, etc. Further yet, in various embodiments that vehicle10can include a roof structure66connected or mounted to at least a portion of the ROPS48. The roof structure66is structured and operable to protect the passenger compartment26, particularly passengers within the passenger compartment26, from environmental elements such as sun, rain, sleet, snow, etc.

The drivetrain44includes a self-cooling continuously variable transmission (CVT)46that is operably connected to the prime mover42to receive torque from the prime mover42, and operably connected to at least one of the rear and front wheels18and22to deliver torque to at least one of the rear and front wheels18and22. In various embodiments, the CVT46can be operably connected to at least one of the rear and front wheels18and22via one or more rear and/or front wheel axles52and/or62that are operably connected to the CVT46. Additionally or alternatively, in various embodiments the CVT46can be operably connected to at least one of the rear and front wheels18and22via a first gearbox50. In such embodiments, the first gearbox50is operably connected to the CVT46and at least one rear and front wheel18and22is operably connected to the first gearbox50via one or more rear and/or front wheel axles52and/or62and/or a driveshaft54, as described further below. For simplicity, the CVT46will be described herein as operably connected to at least one of the rear and front wheels18and22via the first gearbox50.

The CVT46is structured and operable to receive torque (e.g., motive force, e.g., power) generated by the prime mover42and controllably transfer the torque to the first gearbox50. Particularly, when transferring the torque to the first gearbox50, the CVT46is structured and operable to continuously vary the amount of torque delivered to the gearbox50. That is, the amount of torque delivered can continuously be increased, decreased and/or not changed by the CVT46. The first gearbox50is structured and operable to transfer and distribute the torque to one or more of the wheels18and/or22. For example, in various embodiments, the first gearbox50can be operably connected to a rear axle52and structured and operable to transfer and distribute the torque output by the CVT46to at least one of the rear wheels18. The rear axle52can be either a split axle for an independent suspension system, or a one-piece axle. In various other embodiments, in addition to transferring and distributing the torque to at least one of the rear wheels18, the first gearbox50can include a power take off (PTO) such that the first gearbox50can also transfer and distribute the torque output by the CVT46to at least one of the front wheels22, as described below. The first gearbox50can be a torque transfer device such as a transmission and/or a differential and/or a transaxle, etc. For example, in various implementations, the first gearbox50can be a multi-speed gearbox and, in various instances, include a differential for distributing the torque to one or more of the wheels18and/or22.

In some embodiments, the drivetrain44can be configured to provide a 4-wheel drive (4WD) vehicle or a 2-wheel drive (2WD) vehicle, and remain within the scope of the present disclosure. In various embodiments in which the drivetrain44is configured to provide a 2WD vehicle, the vehicle10can be driven by the rear wheels18(e.g., a rear wheel drive vehicle) or by the front wheels22(e.g., a front wheel drive vehicle). In some embodiments in which the vehicle10can be configured as a 4WD vehicle, the vehicle10can be selectively operated in two or more drive modes, such as a 2WD mode and a 4WD mode, through actuation of a switch or other user input device that can be disposed on the instrument panel30.

In the various embodiments in which at least one of the front wheels22receive torque from the CVT46(e.g., front wheel 2WD and/or 4WD embodiments), the drivetrain44can include a driveshaft54and a second gearbox (or differential)58. In such embodiments, the driveshaft54is operably connected at one end to the CVT46or the first gearbox50via a PTO and operably connected at the opposing end to the second gearbox58. The second gearbox58is structured and operable to transfer and distribute the torque output by the CVT46to one or more of the front wheels22via a front axle62. The front axle62can be either a split axle for an independent suspension system, or a one-piece axle.

Additionally, although the prime mover42and CVT46are illustrated, by way of example, in the various figures to be at least partially disposed rearward of a longitudinal center of the vehicle10, it is envisioned that the prime mover42and CVT46can be disposed anywhere along a longitudinal axis of the vehicle10and remain within the scope of the present disclosure. For example, in various embodiments, the prime mover42and/or the CVT46can be disposed forward of the longitudinal center of the vehicle10, e.g., forward of a forward most part of the seating structure38. Furthermore, although the prime mover42, the CVT46, and the first gearbox50are shown, by way of example, to be directly connected with each other, it should be understood that the drivetrain44can include one or more driveshafts (such as driveshaft50) that operably interconnect one or more of the prime mover42, the CVT46, the first gearbox50and/or the second gearbox58based on the respective location of the prime mover42and CVT46along the vehicle longitudinal axis, and the respective 2WD or 4WD configuration of the drivetrain44.

As used herein, the word “forward” and the phrase “forward of” are used to describe the direction from a named component or structure toward the front of the vehicle10. For example, the statement that the prime mover42is mounted to the chassis14“forward of” the longitudinal center means the prime mover42is mounted to the chassis14within an area that extends from the longitudinal center of the chassis14to the front of the chassis14at the front of the vehicle10adjacent the front wheels22. Similarly, as used herein, the word “rearward” and the phrase “rearward of” are used to describe the direction from a named component or structure toward the rear of the vehicle10. For example, the statement that the prime mover42is mounted to the chassis14“rearward of” the longitudinal center means the prime mover42is mounted to the chassis14within an area that extends from the longitudinal center of the chassis14to the rear of the chassis14at the rear of the vehicle10adjacent the rear wheels18.

Referring now toFIGS. 2, 4, 5 and 8, in various embodiments, the present disclosure provides a housing70for the CVT46that is structured and operable to protect a primary pulley74of the CVT46(also referred to as the primary clutch), a secondary pulley78of the CVT46(also referred to as the secondary clutch), a pulley V-belt82of the CVT46, and various other CVT components disposable therein from water, mud, dirt and other debris present in the ambient (exterior) environment. Moreover, as described below, the housing70is structured and operable, in cooperation with rotation of the primary pulley74, to generate a vacuum effect or suction (e.g., creates a difference is air pressure between the ambient environment and an interior of the housing70) that draws ambient air into, and circulates the air through, an interior of the housing70in order to thermally cool the CVT components.

Generally, the housing70comprises an inner cover86, an outer cover90, and a duct panel94. The inner and outer covers86and90are connectable to each other to define an interior chamber96in which the primary pulley74, secondary pulley78and pulley V-belt82are disposed upon assembly of the CVT46. The inner cover86includes an input shaft opening98that is sized and shaped to allow an output shaft102of the prime mover42to extend therethrough. The primary pulley74is connectable to the prime mover output shaft102such that, in operation, rotation of the output shaft102and the torque generated thereby is delivered to the primary pulley74. The inner cover additionally includes a torque output opening106that is sized and shaped to allow the secondary pulley78to be operably connected, e.g., via the first gearbox50, to at least one of the rear and/or front axles52and/or62such that torque output by the secondary pulley78is delivered to at least one of the rear and/or front wheels18and/or22.

For example, in various embodiments, an input shaft110of the gearbox50can extend through the torque output opening106such that the secondary pulley78is connectable to the gearbox input shaft110. Therefore, torque generated by the prime mover42will be delivered via the output shaft102to the primary pulley74, whereafter the primary pulley74will deliver torque, via the pulley V-belt82, to the secondary pulley78, whereafter the torque received at the secondary pulley78will be delivered to the gearbox50.

In various embodiments, the primary pulley74is structured and operable to deliver a continuously variable torque to the secondary pulley78. That is, the primary pulley74is structured and operable to continuously variably increase, unchange, and decrease the torque received from the prime mover output shaft10when transferring the torque to the secondary pulley78. Put another way, a torque transfer ratio of the torque received by the primary pulley74from the prime mover42versus the torque delivered to the secondary pulley78from the primary pulley74can be continuously varied via operation of the primary pulley74.

Referring now toFIGS. 4, 5, 6, 7 and 8, in various embodiments, the primary pulley74comprises a shaft or sleeve118, a static sheave122that is fixedly connected to the shaft118, and a dynamic sheave126structured and operable to rotate with the shaft118and simultaneously controllably move axially along the shaft118in the X+and X−directions. The shaft118is engageable and connectable (e.g., via a splined connection) to the prime mover output shaft102. The static sheave122includes a beveled inner face130and an outer face134. The dynamic sheave126comprises a beveled inner face138and a linear movement mechanism142that is structured and operable to controllably move the dynamic sheave126axially along the shaft118in the X+and X−directions. A V-channel146is formed between the opposing beveled inner faces130and138of the static and dynamic sheaves122and126, and the V-belt82is disposed within the V-channel146. Controlled axial movement of the dynamic sheave126along the shaft118, via the linear movement mechanism142, varies a width of the V-channel130, which in turn varies a diameter, or radial distance from the shaft118, at which the V-belt82travels within the V-channel130, which in turn various the torque transfer ratio of the primary pulley74.

In various implementations, the axial movement of the dynamic sheave126along the shaft118can be controlled by a vehicle controller and/or a CVT controller (not shown). The CVT controller can be a controller that is communicatively connected to, or integrated as part of, a main vehicle controller that is typically understood to be an embedded system that controls one or more of electrical systems and/or subsystems the vehicle10. Generally, the CVT controller can be any suitable hardware and/or software based controller that is structured and operable to control operation of the CVT as described herein. For example, it is envisioned that the CVT controller can comprise one or more, or be part of, application specific integrated circuit(s) (e.g., ASIC(s)), combinational logic circuit(s); field programmable gate array(s) (FPGA); processor(s) (shared, dedicated, or group) that execute software code; and/or other suitable hardware components that provide the CVT functionality described herein and remain within the scope of the present disclosure.

The duct panel94includes a center opening114and is mounted to the inner cover86such that the inner cover input shaft opening98and the duct panel center opening114are adjacent each other. The duct panel center opening114is structured and operable to allow the prime mover output shaft102to extend therethrough. In various embodiments, the inner cover input shaft opening98and the duct panel center opening114can be coaxially aligned. Additionally, the duct panel94is mounted to the inner cover86such that when the primary pulley74is disposed within the interior chamber96, the duct panel94is disposed between the outer face134of the primary pulley static sheave122and the inner cover86. Furthermore, the duct panel94and the inner cover86are structured such that an air duct150is defined between the inner cover86and the duct panel94. Still further, the duct panel94is connected to, or forms at least a portion of, an ambient air inlet162of the housing70such that the air duct150includes the air inlet162and is fluidly connected to the ambient air via the air inlet162. It is envisioned that the air inlet162can be formed within the inner cover86, within the outer cover90, within the duct panel94or any combination thereof when the inner and outer covers86and90and the duct panel94are interconnected.

The air duct150fluidly connects ambient air from an ambient environment154external to the housing70with the interior chamber96of the housing70, via the center opening114. More particularly, the air duct150and the duct panel center opening114are structured and operable to allow the ambient air to be drawn, via a vacuum effect or suction generated by the primary pulley74, into and through the air duct150and into the housing interior chamber96(seeFIGS. 9A and 9B). More specifically, as described below, the rotation of the primary pulley74creates a difference is air pressure between the ambient environment and the interior chamber96of the housing70that draws the ambient air through the air duct150into the housing interior chamber96. As used herein, the term ‘vacuum effect’ will be understood to mean the suction or drawing of air from a first area (e.g., the ambient environment) to a second area (e.g., the interior chamber96of the housing70) caused by creating a lower pressure within the second area (e.g., the interior chamber96of the housing70) than exists at the first area (e.g., the ambient environment). For example, due to the structure of the primary pulley74, as described below, rotation of the primary pulley74will create a lower air pressure within the interior chamber96of the housing70than is present in the ambient environment external to the housing70, thereby generating a vacuum effect that will draw air from the ambient environment into the housing interior chamber96via the air duct150and the duct panel center opening114.

As best illustrated inFIGS. 6 and 7, in various embodiments, the outer face134of the primary pulley static sheave122comprises a plurality of low pressure fins158extending radially outward from the pulley shaft118. The low pressure fins158are structured and operable to generate a vacuum effect at the duct panel center opening114and within the air duct150as the primary pulley74is rotated. The outer face134of the primary pulley static sheave122can include any number of low pressure fins158having any shape and configuration suitable to generate the vacuum effect within the air duct150. Specifically, the low pressure fins158are sized and shaped to generate low pressure within a low pressure gap170between the static sheave outer face134and the duct panel94as the primary pulley74, and hence static sheave122, rotate via rotation of the prime mover output shaft102. The low pressure in turn generates a vacuum effect at the duct panel center opening114and within the air duct150that draws the ambient air though the duct150into the interior chamber96. More specifically, the duct panel94is shaped such that when the primary pulley74is connected to the prime mover output shaft102, the static sheave outer face134that includes a distal edge of each low pressure fin154, is disposed in a specific spaced apart relation with a sheave-side face164of the duct panel94. The spaced apart relation between the primary pulley static sheave outer face134and the duct panel sheave-side face164defines the low pressure gap170therebetween (seeFIG. 8).

Importantly, the low pressure gap170has longitudinal width X (relative to the longitudinal axis of the pulley shaft118) that is calculated to position, locate and/or orient the low pressure fins158in suitable proximity to the duct panel sheave-side face164such that rotation of the low pressure fins158will create the low pressure between the duct panel sheave-side face164and static sheave outer face134, e.g., within the low pressure gap170, which will in turn generate the vacuum effect within the air duct150. The width X is calculated to optimize the generation of vacuum effect within the air duct150based at least on the shape and size of the primary pulley74, the shape and size of the low pressure fins158, the shape and size of the housing interior chamber96, the shape and size of the duct panel94, and the rotational speed range of the primary pulley74(e.g., the rotational speed range of prime mover output shaft102). For example, in various embodiments, the width X of the low pressure gap170can be between approximately 0.010 and 0.100 inches, e.g., between approximately 0.030 inches to 0.080 inches. As a further example, in various embodiments, the width X of the low pressure gap170can be between approximately 0.050 and 0.070.

Additionally, in some embodiments the input shaft opening98in the inner cover86is sufficiently sealed from the ambient environment so that low pressure generated by the low pressure fins158generates the vacuum effect specifically within the air duct150, and that the vacuum effect is enhanced or optimized within the air duct150. For example, in various embodiments, the inner cover can be mounted to the prime mover42, wherein such mounting can provide a sufficient seal around the inner cover input shaft opening98, sealing the input shaft opening98from the ambient environment. In various embodiments, in order to enhance or optimize the vacuum effect generated, the duct panel sheave-side face164has perimeter dimensions that are at least as large as perimeter dimensions of the primary pulley static sheave outer face134. Accordingly, the entire area of the primary pulley static sheave outer face134, and the low pressure fins158can be utilized to create the low pressure within the low pressure gap170, and hence enhance or optimize the vacuum effect generated thereby within the air duct150.

Referring additionally toFIGS. 9A and 9B, in order for the ambient air to be drawn through the air inlet162and air duct150into the housing interior chamber96by rotation of the low pressure fins158, the housing70additionally includes an air exhaust outlet166that fluidly connects the interior chamber96with the ambient environment154. It is envisioned that the exhaust outlet166can be formed within the inner cover86, within the outer cover90, or a combination thereof when the inner and outer covers86and90are connected. Accordingly, as described above, rotation of the primary pulley74and low pressure fins158generates a vacuum effect within the air duct150that draws cool ambient air through the air duct150and into the housing interior chamber96. Subsequently, the rotation of the primary pulley74, the low pressure fins158, the secondary pulley78and the V-belt82disperse the air radially outward around the primary pulley static sheave122, and swirl, mix, circulate the air through the interior chamber96, around and across the primary pulley74, the secondary pulley78and the V-belt82, thereby extracting heat from and thermally cooling the primary pulley74, the secondary pulley78and the V-belt82. Thereafter, the heated circulated air is exhausted from the interior chamber96out into the ambient environment154through the exhaust outlet166. Hence, operation of the CVT46, e.g., rotation of the primary pulley74, generates an air flow from the ambient environment154, though the housing interior chamber96, and back out into the ambient environment. The arrows inFIGS. 9A and 9Bindicate, by way of example, the air flow though and circulation within the housing interior chamber96.

Referring now toFIGS. 10A and 10B, in various embodiments, the CVT46can include an air inlet filter174connectable to the ambient air inlet162. The air inlet filter174is structured and operable to filter the ambient air drawn into the interior chamber96via the air duct150as described above. Particularly, the air inlet filter174is structured and operable to prevent or substantially impede such things as dust, dirt, water, leaves, debris, and other foreign matter from being drawn into the interior chamber96by the vacuum effect generated by the primary pulley static sheave122as described above. The inlet filter174can be any filter having any shape, size and construction suitable to filter the ambient air drawn into the housing interior chamber96. It is envisioned that when connected to the air inlet162the air filter174can be located within the vehicle10anywhere that is conveniently accessible with a good supply of ambient air.

Additionally, in various embodiments, the CVT46can include an air outlet baffle178connectable to the air exhaust outlet166. The air outlet baffle178is structured and operable to prevent or substantially impede foreign matter such as dust, dirt, water, leaves, debris, etc., from entering the ambient air exhaust outlet166. The outlet baffle178can be any baffle or filter having any shape, size and construction suitable to prevent or substantially impede foreign matter such as dust, dirt, water, leaves, debris, etc., from entering the ambient air exhaust outlet166and consequently entering the housing interior chamber96. For example, in various embodiments, as shown by way of example inFIG. 10A, the outlet baffle178can be a single face filter wherein the exhaust air is exhausted through a single face or side182of the filter while the remaining faces or sides of the baffle178are solid or enclosed within a housing. In such embodiments, the baffle182can be position such that the face182is substantially close to another object, e.g., a fender wall or other structure of the vehicle10, so that the exhaust air is freely exhausted, but foreign matter is substantially impeded from contacting the face182, and therefore substantially impeded from entering the housing interior chamber96. Alternatively, in various other embodiments, as shown by way of example inFIG. 10B, the outlet baffle178can be a hook shaped duct that is structured such that when connected to the air exhaust outlet166a distal end portion186of the hook shaped duct is directed downward, e.g., counter to the direction of gravitational force. According, due to the force of gravity, foreign matter will be substantially impeded from traveling upward the distal end portion186and within the baffle182, against the force of gravity. Therefore, foreign matter will be substantially impeded from entering the housing interior chamber96.

The description herein is merely exemplary in nature and, thus, variations that do not depart from the gist of that which is described are intended to be within the scope of the teachings. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and/or functions, it should be appreciated that different combinations of elements and/or functions can be provided by alternative embodiments without departing from the scope of the disclosure. Such variations and alternative combinations of elements and/or functions are not to be regarded as a departure from the spirit and scope of the teachings.